Isothermal pumping analysis for high-altitude tethered balloons.

Science.gov (United States)

Kuo, Kirsty A; Hunt, Hugh E M

2015-06-01

High-altitude tethered balloons have potential applications in communications, surveillance, meteorological observations and climate engineering. To maintain balloon buoyancy, power fuel cells and perturb atmospheric conditions, fluids could be pumped from ground level to altitude using the tether as a hose. This paper examines the pumping requirements of such a delivery system. Cases considered include delivery of hydrogen, sulfur dioxide (SO2) and powders as fluid-based slurries. Isothermal analysis is used to determine the variation of pressures and velocities along the pipe length. Results show that transport of small quantities of hydrogen to power fuel cells and maintain balloon buoyancy can be achieved at pressures and temperatures that are tolerable in terms of both the pipe strength and the current state of pumping technologies. To avoid solidification, transport of SO2 would require elevated temperatures that cannot be tolerated by the strength fibres in the pipe. While the use of particle-based slurries rather than SO2 for climate engineering can reduce the pipe size significantly, the pumping pressures are close to the maximum bursting pressure of the pipe.

Physiologic Tolerance of Descending Thoracic Aortic Balloon Occlusion in a Swine Model of Hemorrhagic Shock

Science.gov (United States)

2013-01-10

Endovascular proximal control of ruptured abdominal aortic aneurysms: the internal aortic clamp. J Cardiovasc Surg (Torino) 2009;50(3):381. 14. Arthurs Z...Starnes B, See C, Andersen C. Clamp Before You Cut: Proximal Control of Ruptured Abdominal Aortic Aneurysms Using Endovascular Balloon Occlusion

Radionuclide assessment of left ventricular function in patients requiring intraoperative balloon pump assistance

International Nuclear Information System (INIS)

Davies, R.A.; Laks, H.; Wackers, F.J.; Berger, H.J.; Williams, B.; Hammond, G.L.; Geha, A.S.; Gottschalk, A.; Zaret, B.L.

1982-01-01

Twenty-three surviving patients who were weaned from cardiopulmonary bypass with intraaortic balloon pump assistance returned for follow-up radionuclide left ventricular (LV) function and thallium 201 perfusion studies at a mean of 23 +/- 3 months following operation. It was found that despite profound intraoperative myocardial depression requiring intraaortic balloon assistance, 13 patients had no change (within 10%) in the resting LV ejection fraction compared with the preoperative measurement. Among all 23 patients, there was no difference between mean (+/- standard error of the mean) preoperative and postoperative resting LV ejection fraction (48 +/- 4 vs 46 +/- 4%, p . not significant [NS]). Only 11 patients had perioperative myocardial infarction documented by new Q waves in the electrocardiogram, by elevation of creatine kinase-MB fraction, or by defects on thallium 201 imaging not explained by documented myocardial infarction before operation. Overall, postoperative resting LV ejection fraction was not different from the preoperative value in patients with perioperative myocardial infarction (44 +/- 7 vs 47 +/- 5%, p . NS). Postoperative resting LV ejection fraction rose by greater than 10% compared with preoperative values in 4 patients (3 with aortic valve replacement), remained within the 10% limit in 9 patients, and fell by greater than 10% in 10 patients (7 with perioperative myocardial infarction). Only 4 out of 16 patients studied at follow-up with exercise radionuclide studies demonstrated a normal LV response to exercise (greater than 5% increase in LV ejection fraction). Thus, among survivors requiring intraaortic balloon pump assistance for weaning from cardiopulmonary bypass, LV performance at rest is frequently preserved. In addition, 11 of the 23 patients had evidence of perioperative myocardial infarction, indicating a component of reversible intraoperative LV dysfunction

Factors associated with pulmonary dysfunction in patients undergoing coronary artery bypass graft surgery with use of intra-aortic balloon pump.

Science.gov (United States)

Amaral Gonçalves Fusatto, Helena; Castilho de Figueiredo, Luciana; Ragonete Dos Anjos Agostini, Ana Paula; Sibinelli, Melissa; Dragosavac, Desanka

2018-01-01

The aim of this study was to identify pulmonary dysfunction and factors associated with prolonged mechanical ventilation, hospital stay, weaning failure and mortality in patients undergoing coronary artery bypass grafting with use of intra-aortic balloon pump (IABP). This observational study analyzed respiratory, surgical, clinical and demographic variables and related them to outcomes. We analyzed 39 patients with a mean age of 61.2 years. Pulmonary dysfunction, characterized by mildly impaired gas exchange, was present from the immediate postoperative period to the third postoperative day. Mechanical ventilation time was influenced by the use of IABP and PaO2/FiO2, female gender and smoking. Intensive care unit (ICU) stay was influenced by APACHE II score and use of IABP. Mortality was strongly influenced by APACHE II score, followed by weaning failure. Pulmonary dysfunction was present from the first to the third postoperative day. Mechanical ventilation time was influenced by female gender, smoking, duration of IABP use and PaO2/FiO2 on the first postoperative day. ICU stay was influenced by APACHE II score and duration of IABP. Mortality was influenced by APACHE II score, followed by weaning failure. Copyright © 2017 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

SU-C-18C-02: Specifcation of X-Ray Projection Angles Which Are Aligned with the Aortic Valve Plane From a Planar Image of a Valvuloplasty Balloon Inflated Across the Aortic Valve

Energy Technology Data Exchange (ETDEWEB)

Fetterly, K; Mathew, V [Mayo Clinic, Rochester, MN (United States)

2014-06-01

Purpose: Transcatheter aortic valve replacement (TAVR) procedures provide a method to implant a prosthetic aortic valve via a minimallyinvasive, catheter-based procedure. TAVR procedures require use of interventional fluoroscopy c-arm projection angles which are aligned with the aortic valve plane to minimize prosthetic valve positioning error due to x-ray imaging parallax. The purpose of this work is to calculate the continuous range of interventional fluoroscopy c-arm projection angles which are aligned with the aortic valve plane from a single planar image of a valvuloplasty balloon inflated across the aortic valve. Methods: Computational methods to measure the 3D angular orientation of the aortic valve were developed. Required inputs include a planar x-ray image of a known valvuloplasty balloon inflated across the aortic valve and specifications of x-ray imaging geometry from the DICOM header of the image. A-priori knowledge of the species-specific typical range of aortic orientation is required to specify the sign of the angle of the long axis of the balloon with respect to the x-ray beam. The methods were validated ex-vivo and in a live pig. Results: Ex-vivo experiments demonstrated that the angular orientation of a stationary inflated valvuloplasty balloon can be measured with precision less than 1 degree. In-vivo pig experiments demonstrated that cardiac motion contributed to measurement variability, with precision less than 3 degrees. Error in specification of x-ray geometry directly influences measurement accuracy. Conclusion: This work demonstrates that the 3D angular orientation of the aortic valve can be calculated precisely from a planar image of a valvuloplasty balloon inflated across the aortic valve and known x-ray geometry. This method could be used to determine appropriate c-arm angular projections during TAVR procedures to minimize x-ray imaging parallax and thereby minimize prosthetic valve positioning errors.

SU-C-18C-02: Specifcation of X-Ray Projection Angles Which Are Aligned with the Aortic Valve Plane From a Planar Image of a Valvuloplasty Balloon Inflated Across the Aortic Valve

International Nuclear Information System (INIS)

Fetterly, K; Mathew, V

2014-01-01

Purpose: Transcatheter aortic valve replacement (TAVR) procedures provide a method to implant a prosthetic aortic valve via a minimallyinvasive, catheter-based procedure. TAVR procedures require use of interventional fluoroscopy c-arm projection angles which are aligned with the aortic valve plane to minimize prosthetic valve positioning error due to x-ray imaging parallax. The purpose of this work is to calculate the continuous range of interventional fluoroscopy c-arm projection angles which are aligned with the aortic valve plane from a single planar image of a valvuloplasty balloon inflated across the aortic valve. Methods: Computational methods to measure the 3D angular orientation of the aortic valve were developed. Required inputs include a planar x-ray image of a known valvuloplasty balloon inflated across the aortic valve and specifications of x-ray imaging geometry from the DICOM header of the image. A-priori knowledge of the species-specific typical range of aortic orientation is required to specify the sign of the angle of the long axis of the balloon with respect to the x-ray beam. The methods were validated ex-vivo and in a live pig. Results: Ex-vivo experiments demonstrated that the angular orientation of a stationary inflated valvuloplasty balloon can be measured with precision less than 1 degree. In-vivo pig experiments demonstrated that cardiac motion contributed to measurement variability, with precision less than 3 degrees. Error in specification of x-ray geometry directly influences measurement accuracy. Conclusion: This work demonstrates that the 3D angular orientation of the aortic valve can be calculated precisely from a planar image of a valvuloplasty balloon inflated across the aortic valve and known x-ray geometry. This method could be used to determine appropriate c-arm angular projections during TAVR procedures to minimize x-ray imaging parallax and thereby minimize prosthetic valve positioning errors

Temporary Percutaneous Aortic Balloon Occlusion to Enhance Fluid Resuscitation Prior to Definitive Embolization of Post-Traumatic Liver Hemorrhage

International Nuclear Information System (INIS)

Matsuoka, Shin; Uchiyama, Katsuhiro; Shima, Hideki; Ohishi, Sonomi; Nojiri, Yoko; Ogata, Hitoshi

2001-01-01

We successfully stabilized severe hemorrhagic shock following traumatic liver injury by percutaneous transcarotid supraceliac aortic occlusion with a 5 Fr balloon catheter. Then we were able to perform transfemoral embolization therapy of the hepatic arterial bleeding source. Transient aortic occlusion using a balloon catheter appears to be a useful adjunct in select cases where stabilization of the patient is necessary to allow successful selective embolization of the bleeding source

The outcomes of intra-aortic balloon pump usage in patients with acute myocardial infarction: a comprehensive meta-analysis of 33 clinical trials and 18,889 patients

Directory of Open Access Journals (Sweden)

Fan ZG

2016-03-01

Full Text Available Zhong-Guo Fan,1,* Xiao-Fei Gao,1,2,* Li-Wen Chen,1 Xiao-Bo Li,1,2 Ming-Xue Shao,1,2 Qian Ji,1 Hao Zhu,1 Yi-Zhi Ren,1 Shao-Liang Chen,1,2 Nai-Liang Tian1,2 1Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, 2Department of Cardiology, Nanjing Heart Center, Nanjing, People’s Republic of China *These authors contributed equally to this work Background: The effects of intra-aortic balloon pump (IABP usage in patients with acute myocardial infarction remain controversial. This study sought to evaluate the outcomes of IABP usage in these patients.Methods: Medline, EMBASE, and other internet sources were searched for relevant clinical trials. The primary efficacy endpoints (in-hospital, midterm, and long-term mortality and secondary endpoints (reinfarction, recurrent ischemia, and new heart failure in the hospital as well as safety endpoints (severe bleeding requiring blood transfusion and stroke in-hospital were subsequently analyzed.Results: Thirty-three clinical trials involving 18,889 patients were identified. The risk of long-term mortality in patients suffering from acute myocardial infarction was significantly decreased following IABP use (odds ratio [OR] 0.66, 95% confidence interval [CI]: 0.48–0.91, P=0.010. Both in-hospital and midterm mortality did not differ significantly between the IABP use group and no IABP use group (in-hospital: OR 0.87, 95% CI: 0.59–1.28, P=0.479; midterm: OR 1.12, 95% CI: 0.53–2.38, P=0.768. IABP insertion was not associated with the risk reduction of reinfarction, recurrent ischemia, or new heart failure. However, IABP use increased the risk of severe bleeding requiring blood transfusion (OR 2.05, 95% CI: 1.29–3.25, P=0.002 and stroke (OR 1.71, 95% CI: 1.04–2.82, P=0.035. In the thrombolytic therapy and cardiogenic shock subgroups, reduced mortality rates following IABP use were observed.Conclusion: IABP insertion is associated with feasible benefits with respect to long

Clinical and hemodynamic effects of intra-aortic balloon pump therapy in chronic heart failure patients with cardiogenic shock.

Science.gov (United States)

Fried, Justin A; Nair, Abhinav; Takeda, Koji; Clerkin, Kevin; Topkara, Veli K; Masoumi, Amirali; Yuzefpolskaya, Melana; Takayama, Hiroo; Naka, Yoshifumi; Burkhoff, Daniel; Kirtane, Ajay; Dimitrios Karmpaliotis, S M; Moses, Jeffrey; Colombo, Paolo C; Garan, A Reshad

2018-03-20

The role of the intra-aortic balloon pump (IABP) in acute decompensated heart failure (HF) with cardiogenic shock (CS) is largely undefined. In this study we sought to assess the hemodynamic and clinical response to IABP in chronic HF patients with CS and identify predictors of response to this device. We retrospectively reviewed all patients undergoing IABP implantation from 2011 to 2016 at our institution to identify chronic HF patients with acute decompensation and CS (cardiac index <2.2 liters/min/m 2 and systolic blood pressure <90 mm Hg or need for vasoactive medications to maintain this level). Clinical deterioration on IABP was defined as failure to bridge to either discharge on medical therapy or durable heart replacement therapy (HRT; durable left ventricular assist device or heart transplant) with IABP alone. We identified 132 chronic HF patients with IABP placed after decompensation with hemodynamic evidence of CS. Overall 30-day survival was 84.1%, and 78.0% of patients were successfully bridged to HRT or discharge without need for escalation of device support. The complication rate during IABP support was 2.3%. Multivariable analysis identified ischemic cardiomyopathy (odds ratio [OR] 3.24, 95% confidence interval [CI] 1.16 to 9.06; p = 0.03) and pulmonary artery pulsatility index (PAPi) <2.0 (OR 5.04, 95% CI 1.86 to 13.63; p = 0.001) as predictors of clinical deterioration on IABP. Overall outcomes with IABP in acute decompensated chronic HF patients are encouraging, and IABP is a reasonable first-line device for chronic HF patients with CS. Baseline right ventricular function, as measured by PAPi, is a major predictor of outcomes with IABP in this population. Copyright © 2018 International Society for the Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

High-pressure balloon dilation in a dog with supravalvular aortic stenosis.

Science.gov (United States)

Pinkos, A; Stauthammer, C; Rittenberg, R; Barncord, K

2017-02-01

A 6-month-old female intact Goldendoodle was presented for diagnostic work up of a grade IV/VI left basilar systolic heart murmur. An echocardiogram was performed and revealed a ridge of tissue distal to the aortic valve leaflets at the sinotubular junction causing an instantaneous pressure gradient of 62 mmHg across the supravalvular aortic stenosis and moderate concentric hypertrophy of the left ventricle. Intervention with a high-pressure balloon dilation catheter was pursued and significantly decreased the pressure gradient to 34 mmHg. No complications were encountered. The patient returned in 5 months for re-evaluation and static long-term reduction in the pressure gradient was noted. Copyright © 2016 Elsevier B.V. All rights reserved.

Fiber-optic intra-aortic balloon therapy and its role within cardiac surgery.

Science.gov (United States)

Yarham, G; Clements, A; Morris, C; Cumberland, T; Bryan, M; Oliver, M; Burrows, H; Mulholland, J

2013-03-01

The patient population has changed and the cardiothoracic team are now operating on patients with more co-morbidity. One of the significant aspects of this increased co-morbidity, which affects both short- and long-term outcomes, is compromised left ventricular function. Intra-aortic balloon pump (IABP) technology offers these patients and the cardiac team an easily accessible, cost-effective, mechanical assist device. Arterial pressure monitoring for IABP therapy: Fluid-filled transducers used to measure the aortic waveform can be unreliable and inconsistent. Fiber-optic manometers located in the very tip of the IAB catheters provide accurate and fast, high quality measurements. This, in turn, presents the opportunity for the hardware and algorithm to measure key markers on the arterial waveform and optimise left ventricular support. It also provides the potential for automatic in vivo calibration, further increasing the accuracy and quality of the IAB support. The effect of fiber-optic IABP therapy on clinical management: A dual centre prospective audit comparing fluid-filled versus fiber-optic arterial pressure monitoring showed a 96% reduction in IAB-related perfusion on-site call-outs (17 vs. 1, respectively) and a 94% reduction in sub-optimal timing (55/98 vs. 2/94, respectively). The improved timing algorithms utilise the pressure information received 50 msecs faster than with fluid-filled transducers, measuring key markers on the pressure waveform and adjusting inflation and deflation accurately on a beat per beat basis. Fiber-optic IAB technology and, specifically, these improved algorithms provide better beat per beat mechanical support. Given our evolving patient population, this technology will not only play an increased role, but will have a significant impact on cardiac surgery.

Intra-aortic balloon shape change: effects on volume displacement during inflation and deflation.

Science.gov (United States)

Khir, Ashraf William; Bruti, Gianpaolo

2013-07-01

It has been observed that operating the intra-aortic balloon at an angle to the horizontal resulted in a reduction of the volume displaced toward the coronary arteries and compromised afterload reduction. Therefore, the aim of this work is to examine whether changing the current balloon shape, which has not been altered for 40 years, could compensate for the negative hemodynamic effects due to angulation. We tested two tapered balloons, increasing diameter (TID) and decreasing diameter (TDD), and compared the results with those obtained from a standard cylindrical balloon. The balloons were tested in vitro at 60 beats/min and a static pressure of 90 mm Hg. The balloons were operated at four angles (0°, 20°, 30°, 45°), and the pressure at three locations along the balloon (base, middle, and tip) was also measured. Flow rate upstream of the tip of the balloon was also measured to indicate the flow displaced toward the coronary circulation. The relative volume displaced toward (VUTVi) and suctioned away from (VUTVd) the simulated ascending aorta, during inflation and deflation, respectively, is reduced when a standard cylindrical balloon is operated at an angle to the horizontal. The TDD provided the greatest VUTVi and also produced the largest pulse pressure during deflation. Although the TID provided less VUTVi and VUTVd at smaller angles, it was not markedly affected by the change of angle. According to these results, different balloon shapes analyzed, with comparable volume to that of a cylindrical balloon, produced greater inflation and deflation benefits, at the horizontal and at a range of angles to the horizontal. Further investigations are required to optimize the shape of the tapered balloons to fit into the available physiological space. © 2013 Wiley Periodicals, Inc. and International Center for Artificial Organs and Transplantation.

Caesarean section combined with temporary aortic balloon occlusion followed by uterine artery embolisation for the management of placenta accreta

International Nuclear Information System (INIS)

Duan, X.-H.; Wang, Y.-L.; Han, X.-W.; Chen, Z.-M.; Chu, Q.-J.; Wang, L.; Hai, D.-D.

2015-01-01

Aim: To determine the efficacy and safety of caesarean section combined with temporary aortic balloon occlusion followed by uterine artery embolisation (UAE) for the treatment of patients with placenta accreta. Materials and methods: This retrospective study involved 42 patients with placenta accreta. All patients underwent caesarean section combined with temporary aortic balloon occlusion followed by UAE through the right femoral approach. Results: All patients were confirmed to have placenta praevia and accreta, including five patients with placenta percreta, at the time of delivery. The technical success rate of the combined treatment was 97.6% (41/42). Forty-one patients underwent successful caesarean section with conservation of the uterus. Hysterectomy was required in one (3.1%) patient. The amount of blood loss and blood transfusion, and the operation time were was 586 ± 355 ml, 422 ± 83 ml and 65.5 ± 10.6 minutes, respectively. The mean postoperative hospital stay, occlusion time and fetal radiation dose were 5.5 ± 2.6 days, 22.4 ± 7.2 minutes and 4.2 ± 2.9 mGy, respectively. There were no significant changes before and 7 days after the endovascular procedure in creatinine levels (56.8 ± 13.8 μmol/l versus 63.4 ± 16.7 μmol/l, p = 0.09) or urea nitrogen (6.3 ± 2.5 μmol/l versus 7.4 ± 3.8 μmol/l, p = 0.17). There were no access-site complications after the endovascular procedure and no complications related to the intervention during follow-up. Conclusion: Temporary aortic balloon occlusion followed by UAE can effectively control postpartum haemorrhage during placental dissection, and reduce transfusion requirements, hysterectomy rate, and operation time in patients with placenta accreta. -- Highlights: •Aortic balloon occlusion can overcome the collateral flow from other arteries. •UAE can effectively manage secondary postpartum haemorrhage. •The aortic balloon can rapidly and easily insert. •The mean

78 FR 36702 - Cardiovascular Devices; Reclassification of Intra-Aortic Balloon and Control Systems (IABP) for...

Science.gov (United States)

2013-06-19

.... FDA-2013-N-0581] Cardiovascular Devices; Reclassification of Intra-Aortic Balloon and Control Systems... Device In the preamble to the proposed rule (44 FR 13369; March 9, 1979), the Cardiovascular Device... Bypass Grafting: A Propensity Score Analysis,'' Interactive Cardiovascular and Thoracic Surgery, vol. 9...

Inflation and deflation timing of the AutoCAT 2 WAVE intra-aortic balloon pump using the autoPilot mode in a clinical setting.

Science.gov (United States)

Bakker, E W M; Visser, K; van der Wal, A; Kuiper, M A; Koopmans, M; Breedveld, R

2012-09-01

The primary goal of this observational clinical study was to register the occurrence of incorrect inflation and deflation timing of an intra-aortic balloon pump in autoPilot mode. The secondary goal was to identify possible causes of incorrect timing. During IABP assistance of 60 patients, every four hours a strip was printed with the IABP frequency set to 1:2. Strips were examined for timing discrepancies beyond 40 ms from the dicrotic notch (inflation) and the end of the diastolic phase (deflation). In this way, 320 printed strips were examined. A total of 52 strips (16%) showed incorrect timing. On 24 of these strips, the incorrect timing was called incidental, as it showed on only one or a few beats. The other 28 cases of erroneous timing were called consistent, as more than 50% of the beats on the strip showed incorrect timing. We observed arrhythmia in 69% of all cases of incorrect timing. When timing was correct, arrhythmia was found on 13 (5%) of 268 strips. A poor quality electrocardiograph (ECG) signal showed on 37% of all strips with incorrect timing and 11% of all strips with proper timing. We conclude that inflation and deflation timing of the IABP is not always correct when using the autoPilot mode. The quality of the ECG input signal and the occurrence of arrhythmia appear to be related to erroneous timing. Switching from autoPilot mode to operator mode may not always prevent incorrect timing.

78 FR 79300 - Cardiovascular Devices; Reclassification of Intra-Aortic Balloon and Control Systems for Acute...

Science.gov (United States)

2013-12-30

.... FDA-2013-N-0581] Cardiovascular Devices; Reclassification of Intra-Aortic Balloon and Control Systems... of these devices into class II. List of Subjects in 21 CFR Part 870 Medical devices, Cardiovascular... Commissioner of Food and Drugs, 21 CFR part 870 is amended as follows: PART 870--CARDIOVASCULAR DEVICES 0 1...

The need for intra aortic balloon pump support following open heart surgery: risk analysis and outcome.

LENUS (Irish Health Repository)

Parissis, Haralabos

2010-01-01

BACKGROUND: The early and intermediate outcome of patients requiring intraaortic balloon pump (IABP) was studied in a cohort of 2697 adult cardiac surgical patients. METHODS: 136 patients requiring IABP (5.04%) support analysed over a 4 year period. Prospective data collection, obtained. RESULTS: The overall operative mortality was 35.3%. The "operation specific" mortality was higher on the Valve population.The mortality (%) as per time of balloon insertion was: Preoperative 18.2, Intraoperative 33.3, postoperative 58.3 (p < 0.05).The incremental risk factors for death were: Female gender (Odds Ratio (OR) = 3.87 with Confidence Intervals (CI) = 1.3-11.6), Smoking (OR = 4.88, CI = 1.23- 19.37), Preoperative Creatinine>120 (OR = 3.3, CI = 1.14-9.7), Cross Clamp time>80 min (OR = 4.16, CI = 1.73-9.98) and IABP insertion postoperatively (OR = 19.19, CI = 3.16-116.47).The incremental risk factors for the development of complications were: Poor EF (OR = 3.16, CI = 0.87-11.52), Euroscore >7 (OR = 2.99, CI = 1.14-7.88), history of PVD (OR = 4.99, CI = 1.32-18.86).The 5 years survival was 79.2% for the CABG population and 71.5% for the valve group. (Hazard ratio = 1.78, CI = 0.92-3.46). CONCLUSIONS: IABP represents a safe option of supporting the failing heart. The need for IABP especially in a high risk Valve population is associated with early unfavourable outcome, however the positive mid term results further justify its use.

The need for intra aortic balloon pump support following open heart surgery: risk analysis and outcome

Directory of Open Access Journals (Sweden)

Apostolakis Efstratios

2010-04-01

Full Text Available Abstract Background The early and intermediate outcome of patients requiring intraaortic balloon pump (IABP was studied in a cohort of 2697 adult cardiac surgical patients. Methods 136 patients requiring IABP (5.04% support analysed over a 4 year period. Prospective data collection, obtained. Results The overall operative mortality was 35.3%. The "operation specific" mortality was higher on the Valve population. The mortality (% as per time of balloon insertion was: Preoperative 18.2, Intraopeartive 33.3, postoperative 58.3 (p The incremental risk factors for death were: Female gender (Odds Ratio (OR = 3.87 with Confidence Intervals (CI = 1.3-11.6, Smoking (OR = 4.88, CI = 1.23- 19.37, Preoperative Creatinine>120 (OR = 3.3, CI = 1.14-9.7, Cross Clamp time>80 min (OR = 4.16, CI = 1.73-9.98 and IABP insertion postoperatively (OR = 19.19, CI = 3.16-116.47. The incremental risk factors for the development of complications were: Poor EF (OR = 3.16, CI = 0.87-11.52, Euroscore >7 (OR = 2.99, CI = 1.14-7.88, history of PVD (OR = 4.99, CI = 1.32-18.86. The 5 years survival was 79.2% for the CABG population and 71.5% for the valve group. (Hazard ratio = 1.78, CI = 0.92-3.46. Conclusions IABP represents a safe option of supporting the failing heart. The need for IABP especially in a high risk Valve population is associated with early unfavourable outcome, however the positive mid term results further justify its use.

Immediate and Short-term Follow-Up of Aortic Coarctation Balloon Angioplasty and Stenting

Directory of Open Access Journals (Sweden)

Hasan Mottaghi Moghadam

2017-12-01

Full Text Available Background Aortic Coarcatation (CoA is one of the congenital heart diseases with the rate of 5-8% of Coronary heart diseases(CHDs. Balloon angioplasty is now one of the effective way of treatment for CoA, native or Re-coarctation (Re-CoA. We aimed to assess the immediate, and short term response to angioplasty and stenting, and also complications. Materials and Methods Balloon angioplasty with our without stenting was performed for 53 patients with native or Re-coarcatation angioplasty (39 balloon angioplasty alone, and 14 balloon and stenting. Pressure gradient across the CoA segment was measured initially by Echo and pre, and Post procedure. Echocardiography was also used for follow up assessment during 24 hours, one and 6 months afterward. Results Among 53 patients, 52.8% were male. There were 98.2% native and 3.8% Re-CoA. The mean age of patients was 8.65 ± 8.37 years, and the mean weight was 25.82±20.73 kg. The mean pressure gradient acrossthe CoA site before angioplasty was 24.88±12.32, and post procedure gradient was 4.77±6.42 (p

A High Performance Pulsatile Pump for Aortic Flow Experiments in 3-Dimensional Models.

Science.gov (United States)

Chaudhury, Rafeed A; Atlasman, Victor; Pathangey, Girish; Pracht, Nicholas; Adrian, Ronald J; Frakes, David H

2016-06-01

Aortic pathologies such as coarctation, dissection, and aneurysm represent a particularly emergent class of cardiovascular diseases. Computational simulations of aortic flows are growing increasingly important as tools for gaining understanding of these pathologies, as well as for planning their surgical repair. In vitro experiments are required to validate the simulations against real world data, and the experiments require a pulsatile flow pump system that can provide physiologic flow conditions characteristic of the aorta. We designed a newly capable piston-based pulsatile flow pump system that can generate high volume flow rates (850 mL/s), replicate physiologic waveforms, and pump high viscosity fluids against large impedances. The system is also compatible with a broad range of fluid types, and is operable in magnetic resonance imaging environments. Performance of the system was validated using image processing-based analysis of piston motion as well as particle image velocimetry. The new system represents a more capable pumping solution for aortic flow experiments than other available designs, and can be manufactured at a relatively low cost.

Laser Fenestration of Aortic Stent-Grafts Followed by Noncompliant vs Cutting Balloon Dilation: A Scanning Electron Microscopy Study.

Science.gov (United States)

Lin, Jing; Parikh, Niraj; Udgiri, Naval; Wang, Shaoxia; Miller, Daniel F; Li, Chaojing; Panneton, Jean; Nutley, Mark; Zhang, Ze; Huang, Yunfan; Lu, Jun; Zhang, Jingyi; Wang, Lu; Guidoin, Robert

2018-06-01

To examine the effects of in situ laser fenestration and subsequent balloon dilation (noncompliant vs cutting) on the graft fabric of 4 aortic stent-graft models. In an in vitro setup, the Zenith TX2, Talent, Endurant, and Anaconda aortic stent-grafts (all made of polyester graft material) were subjected to laser fenestration with a 2.3-mm-diameter probe at low and high energy in a physiologic saline solution followed by balloon dilation of the hole. For the first series of tests, 6-mm-diameter noncompliant balloons were used and replaced for the second series by 6-mm-diameter cutting balloons. Each procedure was performed 5 times (5 fenestrations per balloon type). The fenestrations were examined visually and with light and scanning electron microscopy. Each fenestration demonstrated various degrees of fraying and/or tearing regardless of the device. The monofilament twill weave of the Talent endograft tore in the warp direction up to 7.09±0.46 mm at high energy compared with 2.41±0.26 mm for the Endurant multifilament device. The fenestrations of the 3 endografts with multifilament weave (Zenith, Anaconda, and Endurant) showed more fraying; fenestration areas in the multifilament Endurant were >10 mm 2 at low and high energy. The fenestrations were free of melted fibers, but minor blackening of the filaments was observed in all devices. Overall, the cutting balloons resulted in worse tearing and damage. Of note, the edges of the dilated laser-formed fenestrations of the Talent and the Endurant grafts demonstrated evidence of additional shredded yarns. In situ fenestration does not cause any melting of the polyester; however, the observed structural damage to the fabric construction must be carefully considered. Cutting balloons caused various levels of tearing compared to the noncompliant balloons and cannot be recommended for use in this application. Rather, noncompliant balloons should be employed, but only with endografts constructed from multifilament yarns

Incremental balloon deflation following complete resuscitative endovascular balloon occlusion of the aorta results in steep inflection of flow and rapid reperfusion in a large animal model of hemorrhagic shock.

Science.gov (United States)

Davidson, Anders J; Russo, Rachel M; Ferencz, Sarah-Ashley E; Cannon, Jeremy W; Rasmussen, Todd E; Neff, Lucas P; Johnson, M Austin; Williams, Timothy K

2017-07-01

To avoid potential cardiovascular collapse after resuscitative endovascular balloon occlusion of the aorta (REBOA), current guidelines recommend methodically deflating the balloon for 5 minutes to gradually reperfuse distal tissue beds. However, anecdotal evidence suggests that this approach may still result in unpredictable aortic flow rates and hemodynamic instability. We sought to characterize aortic flow dynamics following REBOA as the balloon is deflated in accordance with current practice guidelines. Eight Yorkshire-cross swine were splenectomized, instrumented, and subjected to rapid 25% total blood volume hemorrhage. After 30 minutes of shock, animals received 60 minutes of Zone 1 REBOA with a low-profile REBOA catheter. During subsequent resuscitation with shed blood, the aortic occlusion balloon was gradually deflated in stepwise fashion at the rate of 0.5 mL every 30 seconds until completely deflated. Aortic flow rate and proximal mean arterial pressure (MAP) were measured continuously over the period of balloon deflation. Graded balloon deflation resulted in variable initial return of aortic flow (median, 78 seconds; interquartile range [IQR], 68-105 seconds). A rapid increase in aortic flow during a single-balloon deflation step was observed in all animals (median, 819 mL/min; IQR, 664-1241 mL/min) and corresponded with an immediate decrease in proximal MAP (median, 30 mm Hg; IQR, 14.5-37 mm Hg). Total balloon volume and time to return of flow demonstrated no correlation (r = 0.016). This study is the first to characterize aortic flow during balloon deflation following REBOA. A steep inflection point occurs during balloon deflation that results in an abrupt increase in aortic flow and a concomitant decrease in MAP. Furthermore, the onset of distal aortic flow was inconsistent across study animals and did not correlate with initial balloon volume or relative deflation volume. Future studies to define the factors that affect aortic flow during balloon

Australasian trends in intra-aortic balloon counterpulsation weaning: results of a postal survey.

Science.gov (United States)

Lewis, Peter A; Mullany, Daniel V; Courtney, Mary; Coyer, Fiona

2006-12-01

To generate baseline data describing Australasian intra-aortic balloon counterpulsation (IABP) weaning practice. A five-part questionnaire was mailed in April 2005 to all 192 intensive care units in Australia and New Zealand. 116 ICUs responded (response rate, 60%), and 54 reported using IABP. Most of the 54 were in hospitals which were public government-funded (65%), had between 100 and 500 beds (69%), and treated a minimum of 11 patients annually with IABP (60%). The most common method of withdrawing IABP support was ratio reduction alone (61%). ICUs most likely to undertake ratio weaning were higherend users of IABP (> 20 cases per annum) (P = 0.04). Other weaning practices involved a combination of ratio followed by volume reduction (17%), volume then ratio (11%), and volume only (4%). Approaching statistical significance, ratio reduction weaning less frequently required IABP reinsertion or inotropic increase after balloon removal (P = 0.07). ICUs with documented weaning policies were less likely to require IABP reinsertion or inotropic increase after balloon removal (P = 0.06). Criteria considered important before IABP weaning or removal were: blood pressure (92%); heart rate (76%); pulmonary artery wedge pressure (59%); noradrenaline dose (78%); adrenaline dose (57%); and dobutamine dose (57%). Ninety per cent of ICUs reported increasing inotropes after balloon removal only rarely (1:50 patients) or occasionally (1:10 patients), while 87% of ICUs reported never needing to reinsert the balloon or only rarely. The Australasian approach to IABP weaning is eclectic. While ratio reduction weaning appears the most successful manner of support withdrawal, it may be a consequence of a volume-outcome relationship, with high- end users achieving better results through IABP familiarity.

Wave energy patterns of counterpulsation: a novel approach with wave intensity analysis.

Science.gov (United States)

Lu, Pong-Jeu; Yang, Chi-Fu Jeffrey; Wu, Meng-Yu; Hung, Chun-Hao; Chan, Ming-Yao; Hsu, Tzu-Cheng

2011-11-01

In counterpulsation, diastolic augmentation increases coronary blood flow and systolic unloading reduces left ventricular afterload. We present a new approach with wave intensity analysis to revisit and explain counterpulsation principles. In an acute porcine model, a standard intra-aortic balloon pump was placed in descending aorta in 4 pigs. We measured pressure and velocity with probes in left anterior descending artery and aorta during and without intra-aortic balloon pump assistance. Wave intensities of aortic and left coronary waves were derived from pressure and flow measurements with synchronization correction. We identified predominating waves in counterpulsation. In the aorta, during diastolic augmentation, intra-aortic balloon inflation generated a backward compression wave, with a "pushing" effect toward the aortic root that translated to a forward compression wave into coronary circulation. During systolic unloading, intra-aortic balloon pump deflation generated a backward expansion wave that "sucked" blood from left coronary bed into the aorta. While this backward expansion wave translated to reduced left ventricular afterload, the "sucking" effect resulted in left coronary blood steal, as demonstrated by a forward expansion wave in left anterior descending coronary flow. The waves were sensitive to inflation and deflation timing, with just 25 ms delay from standard deflation timing leading to weaker forward expansion wave and less coronary regurgitation. Intra-aortic balloon pumps generate backward-traveling waves that predominantly drive aortic and coronary blood flow during counterpulsation. Wave intensity analysis of arterial circulations may provide a mechanism to explain diastolic augmentation and systolic unloading of intra-aortic balloon pump counterpulsation. Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Tackling the Issue of High Postoperative Pacemaker Implantation Rates in Sutureless Aortic Valve Replacement: Should Balloon Inflation be Removed from the Implantation Method of the Perceval Prosthesis?

Science.gov (United States)

Charles Blouin, Mathieu; Bouhout, Ismail; Demers, Philippe; Carrier, Michel; Perrault, Louis; Lamarche, Yoan; El-Hamamsy, Ismail; Bouchard, Denis

2017-05-01

Sutureless aortic valve replacement (AVR) is an emerging alternative to standard AVR in elderly and high-risk patients. This procedure is associated with a high rate of postoperative permanent pacemaker implantation (PPI). The study aim was to assess the impact on the rate of PPI of implanting the Perceval prosthesis without using balloon inflation. A total of 159 patients who underwent sutureless AVR using the Perceval prosthesis was included. Balloon inflation was used in 132 patients (Balloon group) and not used in the remaining 27 (No-Balloon group). Clinical, echocardiographic and electrocardiographic outcomes were assessed. There was no significant difference in PPI rate between the two groups (26% for Balloon group versus 22% in No-Balloon group; p = 0.700). Balloon inflation had no significant impact on the incidence of paravalvular leaks (p = 0.839), or on the need to return to cardiopulmonary bypass (CPB) intraoperatively due to paravalvular leak or unsatisfactory deployment (p >0.999). Mean and peak transaortic pressure gradients were similar between the two groups (p = 0.417 and p = 0.522, respectively). Cross-clamp and CPB times were shorter in the No-Balloon group (49.6 ± 15.9 min versus 61.1 ± 25.6 min and 64.1 ± 26.3 min versus 79.6 ± 35.4 min, respectively; p = 0.027 and p = 0.012, respectively). The two groups had similar postoperative PPI rates. Implanting the Perceval prosthesis without balloon inflation is safe and had no impact on paravalvular leaks, intraoperative complications or hemodynamic results. Reductions in aortic cross-clamp time and CPB time were observed when the balloon was not used.

Vascular Rupture Caused by a Molding Balloon during Endovascular Aneurysm Repair: Case Report

International Nuclear Information System (INIS)

Lee, Hee Young; Do, Young Soo; Park, Hong Suk; Park, Kwang Bo; Kim, Young Wook; Kim, Dong Ik

2011-01-01

Endovascular aneurysm repair (EVAR) has been accepted as an alternative to traditional open surgery in selected patients. Despite the minimally invasiveness of this treatment, several complications may occur during or after EVAR. Complications include endoleak, aortic dissection, distal embolism, or iatrogenic injury to the access artery. However, there are few reports on the vascular rupture caused by a molding balloon during EVAR. We report two cases of infrarenal abdominal aortic aneurysms complicated by procedure-related aortic or iliac artery rupture by the molding balloon during EVAR. In our cases, we observed suddenly abrupt increase of the diameter of the endograft during balloon inflation, because we inflated the balloon rapidly. In conclusion, careful attention must be paid during inflation of the molding balloon to prevent vascular rupture.

Abdominal Aortic Aneurysm (AAA)

Science.gov (United States)

... Professions Site Index A-Z Abdominal Aortic Aneurysm (AAA) Abdominal aortic aneurysm (AAA) occurs when atherosclerosis or plaque buildup causes the ... weak and bulge outward like a balloon. An AAA develops slowly over time and has few noticeable ...

Stent valve implantation in conventional redo aortic valve surgery to prevent patient-prosthesis mismatch.

Science.gov (United States)

Ferrari, Enrico; Franciosi, Giorgio; Clivio, Sara; Faletra, Francesco; Moccetti, Marco; Moccetti, Tiziano; Pedrazzini, Giovanni; Demertzis, Stefanos

2017-03-01

The goal was to show the technical details, feasibility and clinical results of balloon-expandable stent valve implantation in the aortic position during conventional redo open-heart surgery in selected obese patients with a small aortic prosthesis and severe patient-prosthesis mismatch. Two symptomatic overweight patients (body mass index of 31 and 38), each with a small aortic prosthesis (a 4-year-old, 21-mm Hancock II biological valve and a 29-year-old, 23-mm Duromedic mechanical valve), increased transvalvular gradients (59/31 and 74/44 mmHg) and a reduced indexed effective orifice area (0.50 and 0.43 cm 2 /m 2 ) underwent implantation of two 26-mm balloon-expandable Sapien 3 valves during standard on-pump redo valve surgery. Using full re-sternotomy, cardiopulmonary bypass and cardioplegic arrest, the two balloon-expandable stent valves were implanted under direct view using a standard aortotomy, after prosthesis removal and without annulus enlargement. Aortic cross-clamp times were 162 and 126 min; cardiopulmonary bypass times were 178 and 180 min; total surgical times were 360 and 318 min. At discharge, echocardiograms showed transvalvular peak and mean gradients of 13/9 and 23/13 mmHg and indexed effective orifice areas of 0.64 and 1.08 cm 2 /m 2 . The 3-month echocardiographic follow-up showed transvalvular peak and mean gradients of 18/9 and 19/11 mmHg and indexed effective orifice areas of 0.78 cm 2 /m 2 and 0.84 cm 2 /m 2 , with improved symptoms (New York Heart Association class 1). Implantation of a balloon-expandable stent valve during redo aortic valve surgery is feasible in selected cases and prevents patient-prosthesis mismatch in obese patients without need for aortic annulus enlargement. Moreover, in the case of stent valve degeneration, this approach permits additional valve-in-valve procedures with large stent valves and prevents re-redo surgery. © The Author 2016. Published by Oxford University Press on behalf of the

Aortic Regurgitation in Patients Undergoing Transcatheter Aortic Valve Replacement With the Self-Expanding CoreValve Versus the Balloon-Expandable SAPIEN XT Valve.

Science.gov (United States)

Kiramijyan, Sarkis; Magalhaes, Marco A; Koifman, Edward; Didier, Romain; Escarcega, Ricardo O; Baker, Nevin C; Negi, Smita I; Minha, Sa'ar; Torguson, Rebecca; Jiaxiang, Gai; Asch, Federico M; Wang, Zuyue; Okubagzi, Petros; Gaglia, Michael A; Ben-Dor, Itsik; Satler, Lowell F; Pichard, Augusto D; Waksman, Ron

2016-05-01

The incidence of aortic regurgitation (AR) after transcatheter aortic valve replacement (TAVR) in a self-expanding and a balloon-expandable system is controversial. This study aimed to examine the incidence and severity of post-TAVR AR with the CoreValve (CV) versus the Edwards XT Valve (XT). Baseline, procedural, and postprocedural inhospital outcomes were compared. The primary end point was the incidence of post-TAVR AR of any severity, assessed with a transthoracic echocardiogram, in the CV versus XT groups. A multivariate logistic regression analysis was completed to evaluate for correlates of the primary end point. The secondary end points included the change in severity of AR at 30-day and 1-year follow-up. A total of 223 consecutive patients (53% men, mean age 82 years) who had transfemoral TAVR with either a CV (n = 119) or XT (n = 104) were evaluated. The rates of post-TAVR AR in the groups were similar, and there was no evidence of more-than-moderate AR in either group. There were significant differences in the rates of intraprocedural balloon postdilation with the CV (17.1%) versus XT valve (5.8%; p = 0.009) and in the rates of intraprocedural implantation of a second valve-in-valve prosthesis with the CV (9.9%) versus XT valve (2.2%; p = 0.036). There were no significant differences in inhospital safety outcomes between the 2 groups. In conclusion, the incidence of post-TAVR AR is similar between the CV and the XT valve when performed by experienced operators using optimal intraprocedural strategies, as deemed appropriate, to mitigate the severity of AR. Copyright © 2016 Elsevier Inc. All rights reserved.

Evaluation of Factors Influencing Liver Function Test in On-Pump Coronary Artery Bypass Graft Surgery

Directory of Open Access Journals (Sweden)

Shahrbano Shahbazi

2013-12-01

Full Text Available Background: Liver dysfunction during on-pump coronary artery bypass graft surgery (CABG is a rare complication but is associated with significant morbidity and mortality. The ability to identify high-risk patients may be helpful in planning appropriate management strategies. We aimed to evaluate the factors influencing liver function tests during on-pump CABG. Methods: In 146 patients scheduled for on-pump CABG, the liver function test was done preoperatively and on the first postoperative day. Some preoperative and intraoperative risk factors were checked and then the postoperative liver function tests were compared with the preoperative ones. Probable relationships between these changes and the preoperative and intraoperative risk factors were studied. Results: A medical history of diabetes had a significant relationship with the changes in direct bilirubin. Preoperative central venous pressure had a significant relationship with the changes in aspartate aminotransferase and alanine aminotransferase. Use of intra-aortic balloon pump and duration of aortic cross-clamp were significantly related to the changes in the liver function tests except for alanine aminotransferase and alkaline phosphatase. Conclusion: It seems that the techniques for the reduction of cardiopulmonary bypass and aortic cross-clamp duration may be useful to protect liver function. We recommend that a larger population of patients be studied to confirm these findings.

Implante transapical de endoprótese valvada balão-expansível em posição aórtica sem circulação extracorpórea Off-pump transapical balloon-expandable aortic valve endoprosthesis implantation

Directory of Open Access Journals (Sweden)

Diego Felipe Gaia

2009-06-01

ão.OBJECTIVE: The aortic valve replacement is a routine procedure, and involves replacement of the native valve/prosthesis. In most of the patients who undergo such procedure the risk is acceptable, but in some cases, such risk can justify contraindication. The minimally invasive transcatheter aortic valve implantation without cardiopulmonary bypass (CPB has been shown to be viable, with lower morbidity and mortality. The aim of this study was to develop a catheter-mounted aortic bioprosthesis for implantation without CPB. METHODS: After developing in animals, three patients with high EuroSCORE underwent implantation. Case 1: patients with bioprosthesis dysfunction; Case 2: severe aortic stenosis; Case 3: dysfunction of aortic bioprosthesis. After minithoracotomy and under echocardiographic and fluoroscopic control, a balloon catheter was placed on aortic position and inflated. After, a second balloon with valved endoprosthesis was positioned and released under high ventricular rate. Echocardiographic and angiographic controls were performed and the patients were referred to ICU. RESULTS: In the first case, implantation without CPB was possible with appropriate results. The patient evolved with improvement of ventricular function. After, this patient developed bronchopneumonia, tracheoesophageal fistula and died due to mediastinitis. Autopsy confirmed proper valve positioning and leaflets preservation. The second case showed the device migration after inflation of the balloon, with the need for urgent median sternotomy, CPB and conventional valve replacement. This patient evolved well and was discharged from the ICU on the 14th postoperative day without complications. This patient developed respiratory infection, septic shock and died on the 60th postoperative day. The patient from the third case underwent successful implantation. CONCLUSION: The off-pump transapical implantation of catheter-mounted bioprosthesis was shown to be a feasible procedure. Technical details and learning

Retained intraaortic balloon. Case report and review of the literature.

Science.gov (United States)

Grande, A M; Martinelli, L; Graffigna, A; Viganò, M

1995-01-01

We report a case of intraaortic balloon entrapment in a 70-year-old man who underwent emergency triple coronary bypass. Intraaortic balloon rupture caused the formation of a clot inside the balloon that eventually was responsible for the balloon's entrapment at the aortic bifurcation. The patient had severe atherosclerosis of the aorta and iliac arteries. Balloon removal required aorto-iliac exposure and aorto-bifemoral bypass. After 16 months, he is symptom free and at home.

[Anesthetic Management of a Patient Complicated with Marfan Syndrome and Suffering from Stanford Type A Aortic Dissection during Pregnancy].

Science.gov (United States)

Uozaki, Nako; Mizuno, Kaori; Shiraishi, Yoshito; Doi, Matsuyuki; Sato, Shigehito

2015-04-01

We report a case of a 36-year-old woman at 34 weeks of gestation complicated with Marfan syndrome who underwent Bentall type aortic replacement surgery due to Stanford type A aortic dissection after undergoing caesarean section. Since this patient exhibited severe hypotension before coming to the operating room, it was very difficult to determine whether the cardiac surgery or caesarean section should be performed first. In this case, the caesarean section was performed first, followed by Bentall's surgery. Although intra-aortic balloon pumping and percutaneous cardiopulmonary support were required after weaning from the cardiopulmonary bypass, she was discharged on post-operative day (POD) 40 and the baby was discharged on POD 60, without signs of cerebral palsy. Unfortunately, this patient died on POD 57, due to heart failure. We discuss how to determine the priority of surgeries for patients who require emergency surgery for cardiovascular disease during pregnancy.

Repeat transcatheter aortic valve implantation using a latest generation balloon-expandable device for treatment of failing transcatheter heart valves.

Science.gov (United States)

Schaefer, Andreas; Treede, Hendrik; Seiffert, Moritz; Deuschl, Florian; Schofer, Niklas; Schneeberger, Yvonne; Blankenberg, Stefan; Reichenspurner, Hermann; Schaefer, Ulrich; Conradi, Lenard

2016-01-15

Paravalvular leakage (PVL) is a known complication of transcatheter aortic valve implantation (TAVI) and is associated with poor outcome. Besides balloon-post-dilatation, valve-in-valve (ViV) procedures can be taken into consideration to control this complication. Herein we present initial experience with use of the latest generation balloon-expandable Edwards Sapien 3® (S3) transcatheter heart valve (THV) for treatment of failing THVs. Between 01/2014 and 12/2014 three patients (two male, age: 71-80 y, log EUROScore I: 11.89 - 32.63) with failing THVs were refered to our institution for further treatment. THV approach with secondary implantation of an S3 was chosen after mutual agreement of the local interdisciplinary heart team at an interval of 533-1119 days from the index procedure. The performed procedures consisted of: S3 in Sapien XT, JenaValve and CoreValve. Successful transfemoral implantation with significant reduction of PVL was achieved in all cases. No intraprocedural complications occurred regarding placement of the S3 with a postprocedural effective orifice area (EOA) of 1.5-2.5 cm(2) and pressure gradients of max/mean 14/6-36/16 mmHg. 30-day mortality was 0%. At the latest follow-up of 90-530 days, all patients are alive and well with satisfactory THV function. Regarding VARC-2 criteria one major bleeding and one TIA was reported. In the instance of moderate or severe aortic regurgitation after TAVI, S3 ViV deployment is an excellent option to reduce residual regurgitation to none or mild. For further assertions concerning functional outcomes long-term results have to be awaited.

How to perform combined cutting balloon and high pressure balloon valvuloplasty for dogs with subaortic stenosis.

Science.gov (United States)

Kleman, Mandi E; Estrada, Amara H; Maisenbacher, Herbert W; Prošek, Robert; Pogue, Brandon; Shih, Andre; Paolillo, Joseph A

2012-01-01

Subvalvular aortic stenosis (SAS) is one of the most common congenital cardiac malformations in dogs. Unfortunately, the long term success rate and survival data following either open heart surgery or catheter based intervention has been disappointing in dogs with severe subaortic stenosis. Medical therapy is currently the only standard recommended treatment option. A cutting balloon dilation catheter has been used successfully for resistant coronary artery and peripheral pulmonary arterial stenoses in humans. This catheter is unique in that it has the ability to cut, or score, the stenotic region prior to balloon dilatation of the stenosis. The use of cutting balloon valvuloplasty combined with high pressure valvuloplasty for dogs with severe subaortic stenosis has recently been reported to be a safe and feasible alternative therapeutic option. The following report describes this technique, outlines the materials required, and provides some 'tips' for successful percutaneous subaortic balloon valvuloplasty. Copyright © 2012 Elsevier B.V. All rights reserved.

[Application of temporary balloon blocking technique in bone tumors surgery under the aid of CT angiography].

Science.gov (United States)

Fang, Cheng; Hu, Yongcheng; Huang, Hongchao; Xia, Qun; Chen, Xiaopeng; Yuan, Binbin; He, Xin; Wang, Peng

2014-10-01

To study the value of CT angiography (CTA) in the surgical treatment of bone tumors with the temporary balloon blocking technique. A retrospective analysis was made on the clinical data of 36 bone tumor patients between April 2008 and October 2013. There were 22 males and 14 females, aged from 25 to 83 years (mean, 46 years). The tumor located at the sacrococcygeal region in 17 cases, at the ilium in 12 cases, at the pubis in 5 cases, and at the proximal femur in 2 cases. Before surgery, CTA was performed to measure the external diameter of aortaventralis and arteria iliac communis, and the distance between the low renal artery and the abdominal aortic bifurcation as well as mark the anatomical relationship between the low renal artery, the abdominal aortic bifurcation and bony landmarks of vertebral body. According to these data, suitable balloon was chosen and the balloon positioning was guided in the surgery to completely excise tumor assisted by balloon blocking technique. The CTA results showed that the external diameter of aortaventralis and arteria iliaca communis was (1.545 ± 0.248) cm and (1.060 ± 0.205) cm respectively, and the distance between the low renal artery and the abdominal aortic bifurcation was (10.818 ± 1.165) cm. The three-dimensional reconstruction showed that the opening of the low renal artery was mainly located at L1 (16/36, 44.4%) and the abdominal aortic bifurcation mainly located at L4 (22/36, 61.1%). Effective block of abdomial aorta was performed; the blood pressure obviously increased in 3 cases after balloon inflation, and pulse of the left dorsal artery of the foot decreased in 1 case after removal of balloon, which were relieved after expectant treatment. The operation time was 118-311 minutes; the intraoperative blood loss was 200-1800 mL, 21 patients were given blood transfusion, and the amount of blood transfusion was 400-1200 mL; and the aortic clamping time was 40-136 minutes. All patients were followed up 5-44 months

Quantified degree of eccentricity of aortic valve calcification predicts risk of paravalvular regurgitation and response to balloon post-dilation after self-expandable transcatheter aortic valve replacement.

Science.gov (United States)

Park, Jun-Bean; Hwang, In-Chang; Lee, Whal; Han, Jung-Kyu; Kim, Chi-Hoon; Lee, Seung-Pyo; Yang, Han-Mo; Park, Eun-Ah; Kim, Hyung-Kwan; Chiam, Paul T L; Kim, Yong-Jin; Koo, Bon-Kwon; Sohn, Dae-Won; Ahn, Hyuk; Kang, Joon-Won; Park, Seung-Jung; Kim, Hyo-Soo

2018-05-15

Limited data exist regarding the impact of aortic valve calcification (AVC) eccentricity on the risk of paravalvular regurgitation (PVR) and response to balloon post-dilation (BPD) after transcatheter aortic valve replacement (TAVR). We investigated the prognostic value of AVC eccentricity in predicting the risk of PVR and response to BPD in patients undergoing TAVR. We analyzed 85 patients with severe aortic stenosis who underwent self-expandable TAVR (43 women; 77.2±7.1years). AVC was quantified as the total amount of calcification (total AVC load) and as the eccentricity of calcium (EoC) using calcium volume scoring with contrast computed tomography angiography (CTA). The EoC was defined as the maximum absolute difference in calcium volume scores between 2 adjacent sectors (bi-partition method) or between sectors based on leaflets (leaflet-based method). Total AVC load and bi-partition EoC, but not leaflet-based EoC, were significant predictors for the occurrence of ≥moderate PVR, and bi-partition EoC had a better predictive value than total AVC load (area under the curve [AUC]=0.863 versus 0.760, p for difference=0.006). In multivariate analysis, bi-partition EoC was an independent predictor for the risk of ≥moderate PVR regardless of perimeter oversizing index. The greater bi-partition EoC was the only significant parameter to predict poor response to BPD (AUC=0.775, p=0.004). Pre-procedural assessment of AVC eccentricity using CTA as "bi-partition EoC" provides useful predictive information on the risk of significant PVR and response to BPD in patients undergoing TAVR with self-expandable valves. Copyright © 2017 Elsevier B.V. All rights reserved.

Aortic rupture during aortoplasty in Takayasu arteritis – A rare complication: Case report and review of literature

Directory of Open Access Journals (Sweden)

Vimal Mehta

2014-05-01

Full Text Available Balloon angioplasty of the stenosed aorta is usually a relatively simple, yet potentially a catastrophic procedure. Aortic rupture during aortoplasty, though uncommon, carries a high mortality. We report case of a 39-year-old female with aortoarteritis with multiple arterial stenoses whose infra-renal abdominal aorta ruptured during balloon dilatation of the stent deployed in that segment. The site of aortic rupture was temporarily occluded by low-pressure inflation of the same balloon and then was sealed using a stent-graft introduced by contra-lateral femoral arterial access.

Valsartan attenuates intimal hyperplasia in balloon-injured rat aortic arteries through modulating the angiotensin-converting enzyme 2-angiotensin-(1-7)-Mas receptor axis.

Science.gov (United States)

Li, Yonghong; Cai, Shanglang; Wang, Qixin; Zhou, Jingwei; Hou, Bo; Yu, Haichu; Ge, Zhiming; Guan, Renyan; Liu, Xu

2016-05-15

The role of the Mas receptor in the activity of valsartan against intimal hyperplasia is unclear. Herein, we investigated the role of the angiotensin-converting enzyme 2 (ACE2)-angiotensin-(1-7)-Mas receptor axis on the activity of valsartan against intimal hyperplasiain balloon-injured rat aortic arteries. Wistar rats were randomized equally into the sham control group, injured group, and injured plus valsartan (20 mg/kg/d)-treated group. Valsartan significantly attenuated the vascular smooth muscle cell proliferation and intimal and medial thickening on days 14 and 28 after injury. The angiotensin-(1-7) levels as well as ACE2 and Mas receptor mRNA/protein expression were significantly decreased in the injured rats, compared to the uninjured rats; meanwhile, the angiotensin II level as well as the ACE and AT1 receptor mRNA/protein expression were increased (all P valsartan significantly increased the angiotensin-(1-7) levels as well as ACE2 and Mas receptor mRNA/protein expression but decreased the angiotensin II level, ACE and AT1 receptor mRNA/protein expression, as well as the p-ERK protein expression, compared to the injured group (all P valsartan attenuates neointimal hyperplasiain balloon-injured rat aortic arteries through activation of the ACE2-angiotensin-(1-7)-Mas axis as well as inhibition of the ACE-angiotensin II-AT1 and p-ERK pathways. Copyright © 2016 Elsevier Inc. All rights reserved.

An unusual case of aortic rupture after deployment of a bare stent in the treatment of aortic dissection in a patient with giant-cell arteritis.

Science.gov (United States)

Rynio, Pawel; Kazimierczak, Arkadiusz; Gutowski, Piotr; Cnotliwy, Miloslaw

2017-06-01

Giant-cell arteritis is associated with a higher risk of aortic aneurysm and aortic dissection formation. We present a women with aortic dissection type B treated with a stent graft and bare-metal stent implantation. After the stent deployment we noticed aortic rupture, which was successfully treated with implantation of an additional stent graft. This report highlights the difficulty of endovascular therapy in patients with giant-cell arteritis. We have to bear in mind that chronic inflammation of the aorta leads to a more fragile aortic wall than normal. We recommend the use of a stent graft over a bare-metal stent and gentle use of a balloon catheter.

Five-Year Outcomes of the First Pivotal Clinical Trial of Balloon-Expandable Transcatheter Aortic Valve Replacement in Japan (PREVAIL JAPAN).

Science.gov (United States)

Sawa, Yoshiki; Takayama, Morimasa; Goto, Tsuyoshi; Takanashi, Shuichiro; Komiya, Tatsuhiko; Tobaru, Tetsuya; Maeda, Koichi; Kuratani, Toru; Sakata, Yasushi

2017-07-25

Transcatheter aortic valve replacement (TAVR) has been an alternative less invasive therapy for high-surgical risk/inoperable patients with aortic valve stenosis (AS) in Japan. We report 5-year outcomes of the first pivotal clinical trial of TAVR in Japan (PREVAIL JAPAN).Methods and Results:A total of 64 patients with AS who were considered unsuitable candidates for surgery were enrolled at 3 centers in Japan (mean age: 84.3±6.1 years, female: 65.6%, STS score: 9.0±4.5%). Transfemoral approach (TF) and transapical approach (TA) was performed in 37 patients and 27 patients, respectively. At 5 years, freedom from all-cause death was 52.7% (TF: 51.3%, TA: 56.3%). Risk of all stroke at 5-year was 15.8% (TF: 8.9%, TA: 25.5%) and risk of major adverse cardiac and cerebrovascular events at 5 years was 58.0% (TF: 51.3%, TA: 69.2%). Mild or greater aortic regurgitation (AR) at 1 week was not associated with increased all-cause death at 5 years (69.1%) compared with none or trace AR (48.3%) (P=0.184). Patients with high STS score (>8) had higher mortality rate than those with low STS scores (≤8). The 5-year data from PREVAIL JAPAN show the clinical benefit of TAVR and suggest that balloon-expandable TAVR is an effective treatment option for Japanese patients with severe AS who are not suitable for surgery. (Funded by Edwards Lifesciences Limited; ClinicalTrials.gov number, NCT01113983.).

Aorto-aortic intrathoracic bypass in surgical treatment of aortic

International Nuclear Information System (INIS)

Gutierrez Perez, F.; Duran Reyes, A.; Bigalli, D.; Filgueira Berobide, J.

1998-01-01

The prevalence of coarctation of the aorta is 6.5 percent of all congenital heart defects, according to national and international data. There is a restenosis rate of patients after surgery. Factors that influence this evolution depends on the age at which patients underwent surgery for the first time the anatomy of the aortic arch and type of surgical technique. Several procedures can be used to correct the coarctation, which include surgery and balloon catheter dilation. We present here a case of a patient of 22 years old, with a recurrent coarctation of the aorta studied by echocardiography and magnetic resonance imaging. The patient underwent surgery a third time. We used an anterior approach (median sternotomy) and performed an aortic bypass graft, intrathoracic, under cardiopulmonary bypass. Evolved favorably and was discharged on the sixth day of post operative day (Author) [es

Neonatal aortic stenosis.

Science.gov (United States)

Drury, Nigel E; Veldtman, Gruschen R; Benson, Lee N

2005-09-01

Neonatal aortic stenosis is a complex and heterogeneous condition, defined as left ventricular outflow tract obstruction at valvular level, presenting and often requiring treatment in the first month of life. Initial presentation may be catastrophic, necessitating hemodynamic, respiratory and metabolic resuscitation. Subsequent management is focused on maintaining systemic blood flow, either via a univentricular Norwood palliation or a biventricular route, in which the effective aortic valve area is increased by balloon dilation or surgical valvotomy. In infants with aortic annular hypoplasia but adequately sized left ventricle, the Ross-Konno procedure is also an attractive option. Outcomes after biventricular management have improved in recent years as a consequence of better patient selection, perioperative management and advances in catheter technology. Exciting new developments are likely to significantly modify the natural history of this disorder, including fetal intervention for the salvage of the hypoplastic left ventricle; 3D echocardiography providing better definition of valve morphology and aiding patient selection for a surgical or catheter-based intervention; and new transcutaneous approaches, such as duel beam echo, to perforate the valve.

Chimney Technique in Supra-Aortic Branch Reconstruction in China: A Systematic and Critical Review of Chinese Published Experience.

Science.gov (United States)

Zhao, Yang; Shi, Yawei; Wang, Mian; Cui, Jin; Chen, Yitian; Zheng, Liang; Yin, Henghui; Chang, Guangqi

2017-08-01

The chimney graft (CG) technique has been proposed as a complete endovascular supra-aortic branch reconstruction for aortic pathologies. Due to the rapid growth of thoracic endovascular aortic repair (TEVAR) in China, we aimed to investigate the current data of the CG technique in this most populous country. Studies of supra-aortic branch reconstruction using the CG technique from Chinese centers were collected and analyzed. A total of 294 patients from Chinese centers who underwent TEVAR with CGs were included. There were 301 CGs performed, with a technical successful rate of 97.7%. The rate of early type I endoleaks was 7.1%, and the patency rate of the CGs was desirable. Balloon-expandable bare CGs were significantly associated with good early outcomes and a low rate of endoleaks. Current data from China revealed positive outcomes using CGs for supra-aortic branch reconstruction. Balloon-expandable bare CGs may be the first choice according to the data available but should be considered with caution.

Off-Pump Repair of a Post Myocardial Infarction Ventricular Septal Defect

Directory of Open Access Journals (Sweden)

Feridoun Sabzi

2014-01-01

Full Text Available Refractory cardiogenic shock meant that traditional patch repairs requiring cardiopulmonary bypass would be poorly tolerated and external sandwich closure of post myocardial ventricular septal defect (VSD appears to be simple and effective after initial myocardial infarction (MI. The three cases presented with a VSD after of acute MI with or without thrombolysed with streptokinase during patient admission. The general condition of the three patients was poor with pulmonary edema, low cardiac output and renal failure. The heart was approached through a median sternotomy. Off-pump coronary artery bypass grafting of the coronary artery lesion was done first using octopus and beating heart surgery method and latero - lateral septal plication was performed using sandwich technique. Low cardiac output managed with intra-aortic balloon pump in these patients accompanied with inotropic drugs. Post-operative transesophageal echocardiography revealed that VSD was closed completely in one patient and in two patients small residual VSD remained. More experience is required to ascertain whether this technique will become an accepted alternative to patch repairs.

Direct transcatheter aortic valve implantation with self-expandable bioprosthesis: Feasibility and safety

Energy Technology Data Exchange (ETDEWEB)

Fiorina, Claudia, E-mail: clafiorina@yahoo.it [Cardiac Catheterization Laboratory, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Maffeo, Diego; Curello, Salvatore [Cardiac Catheterization Laboratory, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Lipartiti, Felicia [Division of Cardiology, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Chizzola, Giuliano [Cardiac Catheterization Laboratory, Cardiothoracic Department, Spedali Civili, Brescia (Italy); D' Aloia, Antonio [Division of Cardiology, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Adamo, Marianna [Cardiac Catheterization Laboratory, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Mastropierro, Rosy [Division of Cardiothoracic Anestesiology, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Gavazzi, Emanuele [Department of Radiology, University of Brescia, Spedali Civili, Brescia (Italy); Ciccarese, Camilla; Chiari, Ermanna [Division of Cardiology, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Ettori, Federica [Cardiac Catheterization Laboratory, Cardiothoracic Department, Spedali Civili, Brescia (Italy)

2014-06-15

Background: Balloon valvuloplasty has been considered a mandatory step of the transcatheter aortic valve implantation (TAVI), although it is not without risk. The aim of this work was to evaluate the feasibility and safety of TAVI performed without pre-dilation (direct TAVI) of the stenosed aortic valve. Material and Methods: Between June 2012 and June 2013, 55 consecutive TAVI performed without pre-dilation at our institution using the self-expandable CoreValve prosthesis (Medtronic, Minneapolis, MN) were analyzed and compared with 45 pre-dilated TAVI performed the previous year. Inclusion criteria were a symptomatic and severe aortic stenosis. Exclusion criteria were defined as presence of pure aortic regurgitation, degenerated surgical bioprosthesis or bicuspid aortic valve and prior procedure of balloon aortic valvuloplasty performed as a bridge to TAVI. Results: High-burden calcification in the device landing zone, assessed by CT scan, was found in most of the patients. The valve size implanted was similar in both groups. Device success was higher in direct TAVI (85% vs. 64%, p = 0.014), mostly driven by a significant lower incidence of paravalvular leak (PVL ≥2; 9% vs. 33%, p = 0.02). Safety combined end point at 30 days was similar in both groups. Conclusion: Compared to TAVI with pre-dilation, direct TAVI is feasible regardless of the presence of bulky calcified aortic valve and the valve size implanted. Device success was higher in direct TAVI, mostly driven by a lower incidence of paravalvular leak. Safety at 30 days was similar in two groups.

Transcatheter aortic valve implantation and off-pump coronary artery bypass surgery: an effective hybrid procedure in selected patients.

Science.gov (United States)

Mayr, Benedikt; Firschke, Christian; Erlebach, Magdalena; Bleiziffer, Sabine; Krane, Markus; Joner, Michael; Herold, Ulf; Nöbauer, Christian; Lange, Rüdiger; Deutsch, Marcus-André

2018-02-26

Simultaneous surgical off-pump coronary revascularization and transcatheter aortic valve implantation (TAVI) as a hybrid procedure may be a therapeutic option for patients with a TAVI indication who are not suitable for percutaneous coronary intervention and for patients who have an indication for combined surgical aortic valve implantation and coronary artery bypass grafting but present with a porcelain aorta. Early outcomes of these patients are analysed in this study. From February 2011 to April 2017, hybrid TAVI/off-pump coronary artery bypass (OPCAB) was performed in 12 (60%) patients, hybrid TAVI/minimally invasive direct coronary artery bypass in 6 (30%) patients and staged TAVI/OPCAB in 2 (10%) patients. Endpoints of this study were 30-day mortality, device success and postoperative adverse events as defined by the updated Valve Academic Research Consortium (VARC-2). The median age at the time of surgery was 77 years [interquartile range (IQR), 70-81] with a median logistic EuroSCORE and Society of Thoracic Surgeons' Predicted Risk score of 16.1% (IQR, 9.3-28.1) and 3.9% (IQR, 2.2-5.6), respectively. The median Synergy between PCI with Taxus and Cardiac Surgery score was 16.5 (IQR, 9.8-22.8). TAVI implantation routes were transaortic in 9 (45%) patients, transapical and transfemoral in 5 (25%) patients each and transsubclavian in 1 (5%) patient. Complete myocardial revascularization was achieved in 75% of patients. Device success rate was 100%. Paravalvular aortic regurgitation did not exceed mild in any patient. Stroke/transient ischaemic attack, vascular complications and myocardial infarction were not observed. Re-exploration for bleeding was required in 1 (5%) patient. Thirty-day mortality was 0%. Hybrid OPCAB/MIDCAB and TAVI prove to be a safe and effective alternative treatment option in selected higher risk patients.

Genetics Home Reference: supravalvular aortic stenosis

Science.gov (United States)

... and narrower than usual. A thickened aorta is less flexible and resilient to the stress of constant blood flow and pumping of the heart. Over time, the wall of the aorta can become damaged. Aortic narrowing causes the heart to work harder to pump blood through the aorta, resulting ...

Radiotherapy-induced aortic valve disease associated with porcelain aorta

International Nuclear Information System (INIS)

Daitoku, Kazuyuki; Fukui, Kozo; Ichinoseki, Ikkoh; Munakata, Mamoru; Takahashi, Shoichi; Fukuda Ikuo

2004-01-01

Mediastinal irradiation has been reported to induce cardiac disease such as pericarditis, valvular dysfunction, conduction abnormalities, accelerated arteriosclerosis of the coronary arteries, and also calcifications of the ascending aorta. We herein describe a case of radiotherapy-induced porcelain aorta and aortic valve disease and their surgical treatment. The patient was diagnosed with myasthenia gravis (MG) in 1965 (Osserman's type II), and mediastinal irradiation was performed in 1970 for treatment of thymic tumor associated with MG. Thirty years after radiation therapy, complete atrioventricular block and aortic valve disease with severe calcification of the ascending aorta and aortic arch (porcelain aorta) were detected on echo cardiogram and cardiac catheterization. A permanent pacemaker was implanted via the left subclavian vein and aortic valve replacement was performed under extracorporeal circulation established by selective cerebral perfusion and balloon occlusion instead of aortic cross-clamping. As no risk factors of arteriosclerosis such as hypercholesterolemia, hyperglycemia and hypertension were apparent, we concluded that the aortic valve disease and porcelain aorta were primarily induced by radiotherapy. (author)

Feasibility of Angioplasty and Stenting for Abdominal Aortic Lesions Adjacent to Previously Stented Visceral Artery Lesions in Patients with Takayasu Arteritis

International Nuclear Information System (INIS)

Joseph, George; George, Paul V.; Pati, Purendra Kumar; Chandy, Sunil Thomas

2007-01-01

Two young female patients with Takayasu arteritis presented with symptomatic long-segment abdominal aortic stenosis in the vicinity of previously deployed celiac and renal artery stents that projected markedly into the narrowed aortic lumen. Crushing or distortion of the visceral artery stents during aortic angioplasty was avoided by performing simultaneous or alternating balloon dilatations in the aorta and in the visceral artery stents. Consequently, the visceral artery stents remained patent and shortened longitudinally, allowing unhindered deployment of Wallstents in the adjacent aorta and abolition of a pressure gradient across the aortic lesions. Access to side branches covered by the Wallstent was obtained without difficulty, enabling the performance of balloon dilatation in multiple side branches and ostial stent deployment in a renal artery. These techniques could increase the scope of endovascular therapy in the treatment of patients with Takayasu arteritis

Perioperative management of endovascular abdominal aortic aneurysm repair

International Nuclear Information System (INIS)

Wang Haofu; Wang Yuwei; Li Jun; Zhao Zonggang; Qi Sen

2010-01-01

Objective: To summarize the clinical experience of perioperative management in performing endovascular abdominal aortic aneurysm repair (EVAR). Methods: EVAR was performed in 22 patients with abdominal aortic aneurysm. The clinical data were retrospectively analyzed. Before treatment the functions of main organs were evaluated and certain measures were adopted in order to protect them. Useful parameters, including the length, diameter, angle and configuration of the proximal and distal aneurysmal neck, the relationship of the aneurysm to aortic branches, the distance from the lowest renal artery to the bifurcation of abdominal aorta, and the quality of access vessels (such as diameter, tortuosity and calcification degree) were determined and assessed with CTA. According to the parameters thus obtained, the suitable stent-graft with ideal diameter and length was selected, and the optimal surgery pattern was employed. Local anesthesia was employed in 20 patients, among them the local anesthesia had to be changed to general anesthesia in one. Epidural anesthesia was carried out in one patient through the surgically-reconstructed iliac artery access,and general anesthesia was employed in one patient who had Stanford type A aortic dissection. The lowest renal artery must be accurately localized before deployment of stent-graft was started. At least one patent internal iliac artery should be reserved when bilateral internal iliac arteries needed to be covered, to be covered by stages or to be reconstructed. After stent-graft placement, angiography must be performed to find out if there was any endoleak and, if any, to determine the type of endoleak and to deal with it properly. Two cases had proximal type I endoleak, so balloon dilation was employed in one and cuff implantation in another one. Distal type I endoleak occurred in one case, but, unfortunately, the iliac artery ruptured when balloon dilation was employed, therefore the patient had to receive vascular repair

Aortic embolization of an Edwards SAPIEN prosthesis due to sigmoid left ventricular hypertrophy: Case report.

Science.gov (United States)

Yuksel, Isa Öner; Koklu, Erkan; Arslan, Sakir; Cagirci, Goksel; Kucukseymen, Selcuk

2016-06-01

Transcatheter aortic valve implantation (TAVI) is considered an alternative therapy in high-risk patients with severe aortic stenosis. Although a minimally invasive procedure, it is not free from complications, one of which is valve embolization at the time of TAVI. We present a case of embolization of a balloon-expandable aortic valve due to sigmoid left ventricular hypertrophy and managed with a second valve without surgery. The embolized valve was repositioned in the aortic arch between the left common carotid artery and the brachiocephalic trunk. Copyright © 2016 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

The Effect of Infrarenal Aortic Balloon Occlusion on Weaning from Supraceliac Aortic Balloon Occlusion in a Porcine Model (Sus scrofa) of Hemorrhagic Shock

Science.gov (United States)

2017-06-15

all animals , and continued for six hours. Half of the animals were randomly assigned to Zone-3 REBOA for an additional 45 minutes following Zone-1...concentration or resuscitation requirements.Conclusion: In an animal model of hemorrhagic shock and Zone-1 REBOA, subsequent Zone-3 aortic occlusion did not add

[Valvuloplasty with balloon catheter in biologic prosthesis. Reality or illusion].

Science.gov (United States)

Ledesma Velasco, M; Verdín Vázquez, R; Acosta Valdez, J L; Munayer Calderón, J; Salgado Escobar, J L; Arias Monroy, L; Flores Mendoza, J

1989-01-01

We performed catheter balloon valvuloplasty (CBV) on 8 stenotic operatively-excised bioprosthetic valves (2 Hancock and 6 Ionescu Shiley). Pathology of valves before CBV included degenerative changes: commissural fusion by mounds of calcific deposits (2 valves), fibrotic and focally calcified leaflets (7 valves) and stiff and thick valves (1 valve). Inflation of the balloon resulted in commissural splitting (2 valves), leaflet cracks and fractures (3 valves). Removal of the deflated balloon catheter was associated with debris dislodgement (3 valves). In one case the valve was unable to close with potential for acute regurgitation. Thus, CBV of bioprosthetic valves can split fused commissures by similar mechanisms as in native valves. CBV may fracture calcific deposits causing acute emboli. It can also disrupt the leaflets causing acute insufficiency. The findings suggest a limited role of CBV in the treatment of stenotic bioprosthetic valves in mitral and aortic position.

Endoluminal treatment of aortic dissection

Energy Technology Data Exchange (ETDEWEB)

Chavan, Ajay; Lotz, Joachim; Galanski, Michael [Department of Diagnostic Radiology, Hannover Medical School, Carl Neuberg Strasse 1, 30625, Hannover (Germany); Oelert, Frank; Haverich, Axel; Karck, Matthias [Department of Thoracic and Cardiovascular Surgery, Hannover Medical School, Carl Neuberg Strasse 1, 30625, Hannover (Germany)

2003-11-01

Aortic dissection is most often a catastrophic medical emergency which, if untreated, can be potentially fatal. The intention of therapy in patients with aortic dissection is to prevent aortic rupture or aneurysm formation as well as to relieve branch vessel ischaemia. Patients with aortic dissection are often poor candidates for anaesthesia and surgery and the surgical procedure itself is challenging requiring thoracotomy, aortic cross clamping, blood transfusion as well as prolonged hospital stay in some cases. Operative mortality is especially high in patients with critical mesenteric or renal ischaemia. The past decade has experienced the emergence of a number of interventional radiological or minimally invasive techniques which have significantly improved the management of patients with aortic dissection. These include stent grafting for entry site closure to prevent aneurysmatic widening of the false lumen as well as percutaneous techniques such as balloon fenestration of the intimal flap and aortic true lumen stenting to alleviate branch vessel ischaemia. False lumen thrombosis following entry closure with stent grafts has been observed in 86-100% of patients, whereas percutaneous interventions are able to effectively relieve organ ischaemia in approximately 90% of the cases. In the years to come, it is to be expected that these endoluminal techniques will become the method of choice for treating most type-B dissections and will assist in significantly reducing the number of open surgical procedures required for type-A dissections. The intention of this article is to provide an overview of the current status of these endoluminal techniques based on our own experience as well as on a review of the relevant literature. (orig.)

Endoluminal treatment of aortic dissection

International Nuclear Information System (INIS)

Chavan, Ajay; Lotz, Joachim; Galanski, Michael; Oelert, Frank; Haverich, Axel; Karck, Matthias

2003-01-01

Aortic dissection is most often a catastrophic medical emergency which, if untreated, can be potentially fatal. The intention of therapy in patients with aortic dissection is to prevent aortic rupture or aneurysm formation as well as to relieve branch vessel ischaemia. Patients with aortic dissection are often poor candidates for anaesthesia and surgery and the surgical procedure itself is challenging requiring thoracotomy, aortic cross clamping, blood transfusion as well as prolonged hospital stay in some cases. Operative mortality is especially high in patients with critical mesenteric or renal ischaemia. The past decade has experienced the emergence of a number of interventional radiological or minimally invasive techniques which have significantly improved the management of patients with aortic dissection. These include stent grafting for entry site closure to prevent aneurysmatic widening of the false lumen as well as percutaneous techniques such as balloon fenestration of the intimal flap and aortic true lumen stenting to alleviate branch vessel ischaemia. False lumen thrombosis following entry closure with stent grafts has been observed in 86-100% of patients, whereas percutaneous interventions are able to effectively relieve organ ischaemia in approximately 90% of the cases. In the years to come, it is to be expected that these endoluminal techniques will become the method of choice for treating most type-B dissections and will assist in significantly reducing the number of open surgical procedures required for type-A dissections. The intention of this article is to provide an overview of the current status of these endoluminal techniques based on our own experience as well as on a review of the relevant literature. (orig.)

Fracture of the delivery balloon shaft during balloon-expandable prosthesis alignment during implantation of an Edwards SAPIEN 3.

Science.gov (United States)

Arai, Takahide; Hovasse, Thomas; Chevalier, Bernard

2018-04-01

The expandable sheath was designed with a lower profile in order to reduce the incidence of vascular complications of transcatheter aortic valve implantation using transfemoral approach. However, once the prosthesis has crossed the sheath, it could be difficult to retrieve it from the body. This is the first case of successful bail-out in an instance of delivery balloon shaft malfunction subsequent to the crossing of an expandable sheath during implantation of an Edwards SAPIEN 3 prosthesis. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Is there a role for upper-extremity intra-aortic balloon counterpulsation as a bridge-to-recovery or a bridge-to-transplant in the treatment of end-stage heart failure?

Science.gov (United States)

Nwaejike, Nnamdi; Son, Andre Y; Milano, Carmelo A; Daneshmand, Mani A

2017-10-01

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: Is there a role for upper-extremity intra-aortic balloon pump counterpulsation (UE-IABP) in the treatment of end-stage heart failure? Altogether 230 papers were found using the reported search, of which 6 papers represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Of the 163 bridge-to-transplantation (BTT) patients, 141 (86.5%) were successfully transplanted and of the 9 bridge-to-recovery (BTR) patients, 6 (66.7%) were successfully weaned from the device. Length of support ranged from 3 to 152 days, and the most frequent complications were device malfunction or migration necessitating exchange or repositioning, occurring at a collective rate of 37.3%. UE-IABP is a minimally invasive and cost-effective strategy that provides haemodynamic support while preserving both the mediastinum and the functional status in BTR and BTT patients who may not tolerate more invasive modes of mechanical circulatory support. We conclude that UE-IABP can be used as a bridge-to-recovery (BTR) or transplant (BTT) in patients with end-stage heart failure. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Heart failure - surgeries and devices

Science.gov (United States)

... surgery; HF - surgery; Intra-aortic balloon pumps - heart failure; IABP - heart failure; Catheter based assist devices - heart failure ... problem may cause heart failure or make heart failure worse. Heart valve surgery may be needed to repair or ...

Endovascular Treatment of Occlusive Lesions in the Aortic Bifurcation with Kissing Polytetrafluoroethylene-Covered Stents

NARCIS (Netherlands)

Grimme, F.A.B.; Spithoven, J.H.; Zeebregts, C.J.A.; Scharn, D.M.; Reijnen, M.M.

2015-01-01

PURPOSE: To determine the clinical outcomes of polytetrafluoroethylene covered balloon expandable stents (CBESs) in occlusive lesions of the aortic bifurcation in a kissing stent configuration. MATERIALS AND METHODS: The study included 69 consecutive patients (29 men, 40 women) who underwent kissing

Endovascular Treatment of Occlusive Lesions in the Aortic Bifurcation with Kissing Polytetrafluoroethylene-Covered Stents

NARCIS (Netherlands)

Grimme, Frederike A. B.; Spithoven, J. Hans; Zeebregts, Clark J.; Scharn, Dirk M.; Reijnen, Michel M. P. J.

Purpose: To determine the clinical outcomes of polytetrafluoroethylene covered balloon expandable stents (CBESs) in occlusive lesions of the aortic bifurcation in a kissing stent configuration. Materials and Methods: The study included 69 consecutive patients (29 men, 40 women) who underwent kissing

Análise dos resultados imediatos da cirurgia de revascularização do miocárdio com e sem circulação extracorpórea Analysis of immediate results of on-pump versus off-pump coronary artery bypass grafting surgery

Directory of Open Access Journals (Sweden)

Marcos Antonio Cantero

2012-03-01

number of grafts per patient was 2.48 ± 0.43 in off-pump group and 2.90 ± 0.59 in on-pump group. In the off-pump group, 97.8% of patients received an internal thoracic artery graft, while on-pump group the percentage was 94.1% (P = 0.03. The rate of complete revascularization was similar in both groups. In off-pump group, the circumflex artery was revascularized in 48.9% and 68.2% in the onpump group (P = 0.01. Hospital mortality was 4.3% and 4.7%, respectively in the off-pump group in the on-pump group (P = 0.92. Off-pump group had fewer complications in relation to perioperative myocardial infarction (P = 0.02 and use of intra-aortic balloon pump (P = 0.01. CONCLUSION: The off-pump CABG is a safe procedure with hospital mortality similar to that observed in on-pump CABG, with lower rates of complications and less need for intra-aortic balloon.

Emergency aortic valve replacement and Caesarian section in a primigravida with severe aortic stenosis: a case report.

Science.gov (United States)

Kochhar, Puneet K; Zutshi, V; Shamsunder, S; Batra, S; Ghosh, P

2011-01-01

Congenital bicuspid aortic valve with severe aortic stenosis (AS) is a rare condition (3-6% of patients with congenital heart disease). Pregnancy in these patients carries a high risk of maternal and fetal mortality. With advancing gestational age, these women may develop cardiac failure due to increased cardiorespiratory requirements. When medical therapy proves insufficient, cardiac surgery becomes mandatory to save the patient's life. Balloon valvuloplasty is only palliative treatment, the duration of benefit being only 6 months. Valve replacement is thus recommended. Cardiopulmonary bypass (CPB) surgery with valve replacement has been reported to carry a lower risk of maternal mortality (1.5-13%) but a very high fetal risk (16-40%). This paper reports the case of a 30-year-old primigravida with severe AS with bicuspid aortic valve and pulmonary congestion clinically uncontrolled, in whom CPB surgery and aortic valve replacement was performed as an emergency procedure, along with a lower segment Caesarian section. The outcome of unrelieved severe symptomatic AS in pregnancy is poor. Multidisciplinary management is important to avoid deterioration in cardiac performance in parturients with severe AS. CPB during pregnancy carries a high risk to the fetus. Therefore, open heart surgery during pregnancy should be advised only in extreme emergencies (ie, heart failure refractory to conventional therapy).

Clinical efficacy of transcatheter aortic valve replacement for severe aortic stenosis in high-risk patients: the PREVAIL JAPAN trial.

Science.gov (United States)

Sawa, Yoshiki; Takayama, Morimasa; Mitsudo, Kazuaki; Nanto, Shinsuke; Takanashi, Shuichiro; Komiya, Tatsuhiko; Kuratani, Toru; Tobaru, Tetsuya; Goto, Tsuyoshi

2015-01-01

Transcatheter aortic valve replacement (TAVR) is suggested to be less invasive and/or equally effective in comparison to conventional aortic valve replacement for high-risk symptomatic aortic stenosis patients. We herein report the initial results of a pivotal clinical trial of TAVR in Japan (the PREVAIL JAPAN). Sixty-four aortic stenosis patients (mean age 84.3 ± 6.1 years) not suitable for surgery were enrolled at three centers in Japan, with a primary composite endpoint of the 6-month post-procedure improvements in the aortic valve area and New York Heart Association (NYHA) functional classification. A transfemoral approach was used in 37 patients and a transapical approach was used in 27. The device success rate was 91.9 %. After 30 days and 6 months, the rates of mortality from any cause were 8.1 and 11.3 %, respectively. At 6 months, symptomatic stroke was found in 3.1 % of the patients, and silent infarction in 7.8 %. The aortic valve area and mean pressure gradient were significantly improved over time with both approaches (p < 0.001). At 6 months, the NYHA functional classification based on a conventional physician's assessment was improved in 87.9 % of the patients. We found results that were equivalent to those in other major TAVR trials, such as an acceptable 30-day survival (91.9 %), suggesting that balloon-expandable TAVR is effective for small Japanese AS patients classified as high-risk or inoperable.

Three-year hemodynamic performance, left ventricular mass regression, and prosthetic-patient mismatch after rapid deployment aortic valve replacement in 287 patients.

Science.gov (United States)

Haverich, Axel; Wahlers, Thorsten C; Borger, Michael A; Shrestha, Malakh; Kocher, Alfred A; Walther, Thomas; Roth, Matthias; Misfeld, Martin; Mohr, Friedrich W; Kempfert, Joerg; Dohmen, Pascal M; Schmitz, Christoph; Rahmanian, Parwis; Wiedemann, Dominik; Duhay, Francis G; Laufer, Günther

2014-12-01

Superior aortic valve hemodynamic performance can accelerate left ventricular mass regression and enhance survival and functional status after surgical aortic valve replacement. This can be achieved by rapid deployment aortic valve replacement using a subannular balloon-expandable stent frame, which functionally widens and reshapes the left ventricular outflow tract, to ensure a larger effective orifice area compared with conventional surgical valves. We report the intermediate-term follow-up data from a large series of patients enrolled in the Surgical Treatment of Aortic Stenosis With a Next Generation Surgical Aortic Valve (TRITON) trial. In a prospective, multicenter (6 European hospitals), single-arm study, 287 patients with aortic stenosis underwent rapid deployment aortic valve replacement using a stented trileaflet bovine pericardial bioprosthesis. Core laboratory echocardiography was performed at baseline, discharge, and 3 months, 1 year, and 3 years after rapid deployment aortic valve replacement. The mean patient age was 75.7 ± 6.7 years (range, 45-93; 49.1% women). The mean aortic valve gradient significantly decreased from discharge to 3 years of follow-up. The mean effective orifice area remained stable from discharge to 3 years. At 1 year, the left ventricular mass index had decreased by 14% (P replacement using a subannular balloon-expandable stent frame demonstrated excellent hemodynamic performance and significant left ventricular mass regression. With continued follow-up, future studies will establish whether these favorable structural changes correlate with improvement in long-term survival and functional status. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

High-risk Trans-Catheter Aortic Valve Replacement in a Failed Freestyle Valve with Low Coronary Height: A Case Report.

Science.gov (United States)

Karimi, Ashkan; Pourafshar, Negiin; Dibu, George; Beaver, Thomas M; Bavry, Anthony A

2017-06-01

A 55-year-old male with a history of two prior cardiac surgeries presented with decompensated heart failure due to severe bioprosthetic aortic valve insufficiency. A third operation was viewed prohibitively high risk and valve-in-valve trans-catheter aortic valve replacement was considered. There were however several high-risk features and technically challenging aspects including low coronary ostia height, poor visualization of the aortic sinuses, and difficulty in identification of the coplanar view due to severe aortic insufficiency, and a highly mobile aortic valve mass. After meticulous peri-procedural planning, trans-catheter aortic valve replacement was carried out with a SAPIEN 3 balloon-expandable valve without any complication. Strategies undertaken to navigate the technically challenging aspects of the case are discussed.

Simultaneous rota-stenting and transcatheter aortic valve implantation for patients with heavily calcified coronary stenosis and aortic stenosis

Directory of Open Access Journals (Sweden)

Yung-Tsai Lee

2016-09-01

Full Text Available Given that coronary artery disease (CAD in octogenarians undergoing transcatheter aortic valve implantation (TAVI often presents with more complex lesions and extensive calcification, rotational atherectomy (RA may be needed in some cases before stenting. However, data regarding the feasibility and safety of simultaneous RA during TAVI using the Medtronic CoreValve (MCV; Medtronic, Minneapolis, MN, USA system are lacking. Three out of 107 (2.8% patients (2 females, average age 85.6 years, mean aortic valve area 0.5 cm2, mean left ventricular ejection fraction 39%, mean Logistic EuroScore 70%, with complex, heavily calcified coronary stenosis, and severe valvular aortic stenosis (AS were treated with TAVI and RA due to high surgical risk. After balloon valvuloplasty, all coronary lesions were successfully treated with RA and stenting, immediately followed by transfemoral TAVI with a self-expandable MCV. Our data suggested that in the very elderly patients with severe and heavily calcified CAD and AS who were turned down for cardiac surgery, RA and stenting followed by TAVI may be performed successfully in a combined, single-stage procedure.

The development of coastal diffusion observation method with a captive balloon

International Nuclear Information System (INIS)

Fukuda, Masaaki; Yamada, Masaharu

1980-03-01

Apparatus whereby the dye cloud in a coastal area in diffusion experiment can be photographed was developed. It consists of a vinyl balloon two meters in diameter, a photographic device with the camera shutter released by wireless signals from the ground, and a winch to raise or lower the balloon. A maximum height of the balloon for taking photographs is 1000 m. During the single balloon flight, thirty photographs can be taken. With the balloon at a certain height, dye as the tracer in diffusion experiment is released at sea surface or a certain sea depth by dye-throwing means or pump, and then taking the photographs is started. Movement and diffusion of the dye are analyzed by means of the photographs taken. The apparatus is simple in mechanism and easy to transport. Dye experiment is possible in the surfe zone where a boat cannot enter. It is impossible, however, to raise the balloon in strong wind or sea breeze. Typical results of the dye diffusion experiment with the apparatus are given. (author)

Three-year-old child with middle aortic syndrome treated by endovascular stent implantation.

Science.gov (United States)

Moszura, Tomasz; Goreczny, Sebastian; Dryzek, Pawel; Niwald, Marek

2013-04-01

Middle aortic syndrome (MAS) is an extremely rare anomaly and represents both a diagnostic and therapeutic challenge, particularly in young children. A case of a 3.5 year-old child with MAS and arterial hypertension is reported, where owing to the patient's young age and the length of the hypoplastic aortic segment, surgical correction with end-to-end anastomosis was not feasible. Instead of palliative bypass grafting between the thoracic and abdominal aorta, successful percutaneous balloon angioplasty and stenting of the lesion was performed with the assistance of three-dimensional rotational angiography.

Lifting options for stratospheric aerosol geoengineering: advantages of tethered balloon systems.

Science.gov (United States)

Davidson, Peter; Burgoyne, Chris; Hunt, Hugh; Causier, Matt

2012-09-13

The Royal Society report 'Geoengineering the Climate' identified solar radiation management using albedo-enhancing aerosols injected into the stratosphere as the most affordable and effective option for geoengineering, but did not consider in any detail the options for delivery. This paper provides outline engineering analyses of the options, both for batch-delivery processes, following up on previous work for artillery shells, missiles, aircraft and free-flying balloons, as well as a more lengthy analysis of continuous-delivery systems that require a pipe connected to the ground and supported at a height of 20 km, either by a tower or by a tethered balloon. Towers are shown not to be practical, but a tethered balloon delivery system, with high-pressure pumping, appears to have much lower operating and capital costs than all other delivery options. Instead of transporting sulphuric acid mist precursors, such a system could also be used to transport slurries of high refractive index particles such as coated titanium dioxide. The use of such particles would allow useful experiments on opacity, coagulation and atmospheric chemistry at modest rates so as not to perturb regional or global climatic conditions, thus reducing scale-up risks. Criteria for particle choice are discussed, including the need to minimize or prevent ozone destruction. The paper estimates the time scales and relatively modest costs required if a tethered balloon system were to be introduced in a measured way with testing and development work proceeding over three decades, rather than in an emergency. The manufacture of a tether capable of sustaining the high tensions and internal pressures needed, as well as strong winds, is a significant challenge, as is the development of the necessary pumping and dispersion technologies. The greatest challenge may be the manufacture and launch of very large balloons, but means have been identified to significantly reduce the size of such balloons or aerostats.

Different transcatheter strategies for aortic coarctation associated with patent ductus arteriosus

Directory of Open Access Journals (Sweden)

Anil Kumar Singhi

2012-07-01

Conclusions: In coarctation with patent ductus arteriosus associated with good sized aortic isthmus, closure of duct with duct occluder device and balloon aortoplasty would correct the lesions. If there is isthmic hypoplasia, device closure of the duct and stenting of the coarctation is needed. Covered stent is a reasonable alternative only in presence of non dilated descending aorta.

Effect of Body Mass Index on Postoperative Complications in ...

African Journals Online (AJOL)

Postoperative stroke, postoperative atrial fibrillation (AF) and intra-aortic balloon pump (IABP) use were not associated with BMI. In linear regression analysis, significant correlations between low BMI, reintubation, ICU stay time and intubation time were found. Re-exploration for bleeding was significantly correlated with ...

Continuous-flow cardiac assistance: effects on aortic valve function in a mock loop.

Science.gov (United States)

Tuzun, Egemen; Rutten, Marcel; Dat, Marco; van de Vosse, Frans; Kadipasaoglu, Cihan; de Mol, Bas

2011-12-01

As the use of left ventricular assist devices (LVADs) to treat end-stage heart failure has become more widespread, leaflet fusion--with resul-tant aortic regurgitation--has been observed more frequently. To quantitatively assess the effects of nonpulsatile flow on aortic valve function, we tested a continuous-flow LVAD in a mock circulatory system (MCS) with an interposed valve. To mimic the hemodynamic characteristics of LVAD patients, we utilized an MCS in which a Jarvik 2000 LVAD was positioned at the base of a servomotor-operated piston pump (left ventricular chamber). We operated the LVAD at 8000 to 12,000 rpm, changing the speed in 1000-rpm increments. At each speed, we first varied the outflow resistance at a constant stroke volume, then varied the stroke volume at a constant outflow resistance. We measured the left ventricular pressure, aortic pressure, pump flow, and total flow, and used these values to compute the change, if any, in the aortic duty cycle (aortic valve open time) and transvalvular aortic pressure loads. Validation of the MCS was demonstrated by the simulation of physiologic pressure and flow waveforms. At increasing LVAD speeds, the mean aortic pressure load steadily increased, while the aortic duty cycle steadily decreased. Changes were consistent for each MCS experimental setting, despite variations in stroke volume and outflow resistance. Increased LVAD flow results in an impaired aortic valve-open time due to a pressure overload above the aortic valve. Such an overload may initiate structural changes, causing aortic leaflet fusion and/or regurgitation. Copyright © 2011 Elsevier Inc. All rights reserved.

Transcatheter aortic valve implantation for failing surgical aortic bioprosthetic valve: from concept to clinical application and evaluation (part 2).

Science.gov (United States)

Piazza, Nicolo; Bleiziffer, Sabine; Brockmann, Gernot; Hendrick, Ruge; Deutsch, Marcus-André; Opitz, Anke; Mazzitelli, Domenico; Tassani-Prell, Peter; Schreiber, Christian; Lange, Rüdiger

2011-07-01

This study sought to review the acute procedural outcomes of patients who underwent transcatheter aortic valve (TAV)-in-surgical aortic valve (SAV) implantation at the German Heart Center, Munich, and to summarize the existing literature on TAV-in-SAV implantation (n = 47). There are several case reports and small case series describing transcatheter aortic valve implantation for a failing surgical aortic valve bioprosthesis (TAV-in-SAV implantation). From January 2007 to March 2011, 20 out of 556 patients underwent a TAV-in-SAV implantation at the German Heart Center Munich. Baseline characteristics and clinical outcome data were prospectively entered into a dedicated database. The mean patient age was 75 ± 13 years, and the mean logistic European System for Cardiac Operative Risk Evaluation and Society of Thoracic Surgeons' Risk Model scores were 27 ± 13% and 7 ± 4%, respectively. Of the 20 patients, 14 had stented and 6 had stentless surgical bioprostheses. Most cases (12 of 20) were performed via the transapical route using a 23-mm Edwards Sapien prosthesis (Edwards Lifesciences, Irvine, California). Successful implantation of a TAV in a SAV with the patient leaving the catheterization laboratory alive was achieved in 18 of 20 patients. The mean transaortic valve gradient was 20.0 ± 7.5 mm Hg. None-to-trivial, mild, and mild-to-moderate paravalvular aortic regurgitation was observed in 10, 6, and 2 patients, respectively. We experienced 1 intraprocedural death following pre-implant balloon aortic valvuloplasty ("stone heart") and 2 further in-hospital deaths due to myocardial infarction. TAV-in-SAV implantation is a safe and feasible treatment for high-risk patients with failing aortic bioprosthetic valves and should be considered as part of the armamentarium in the treatment of aortic bioprosthetic valve failure. Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Apical ballooning syndrome complicated by acute severe mitral regurgitation with left ventricular outflow obstruction – Case report

Directory of Open Access Journals (Sweden)

Celermajer David S

2007-02-01

Full Text Available Abstract Background Apical ballooning syndrome (or Takotsubo cardiomyopathy is a syndrome of transient left ventricular apical ballooning. Although first described in Japanese patients, it is now well reported in the Caucasian population. The syndrome mimicks an acute myocardial infarction but is characterised by the absence of obstructive coronary disease. We describe a serious and poorly understood complication of Takotsubo cardiomyopathy. Case Presentation We present the case of a 65 year-old lady referred to us from a rural hospital where she was treated with thrombolytic therapy for a presumed acute anterior myocardial infarction. Four hours after thrombolysis she developed acute pulmonary oedema and a new systolic murmur. It was presumed she had acute mitral regurgitation secondary to a ruptured papillary muscle, ischaemic dysfunction or an acute ventricular septal defect. Echocardiogram revealed severe mitral regurgitation, left ventricular apical ballooning, and systolic anterior motion of the mitral valve with significant left ventricular outflow tract gradient (60–70 mmHg. Coronary angiography revealed no obstructive coronary lesions. She had an intra-aortic balloon pump inserted with no improvement in her parlous haemodynamic state. We elected to replace her mitral valve to correct the outflow tract gradient and mitral regurgitation. Intra-operatively the mitral valve was mildly myxomatous but there were no structural abnormalities. She had a mechanical mitral valve replacement with a 29 mm St Jude valve. Post-operatively, her left ventricular outflow obstruction resolved and ventricular function returned to normal over the subsequent 10 days. She recovered well. Conclusion This case represents a serious and poorly understood association of Takotsubo cardiomyopathy with acute pulmonary oedema, severe mitral regurgitaton and systolic anterior motion of the mitral valve with significant left ventricular outflow tract obstruction. The

More than just a urinary catheter — Haemorrhage control by using a Foley catheter in a penetrating aortic root injury

Directory of Open Access Journals (Sweden)

Adel Elmoghrabi

2016-08-01

Full Text Available The prevalence of great vessel injuries in thoracic trauma is reported at 0.3–10%, predominantly due to a penetrating mechanism. Thoracic aortic injuries, more specifically those within proximity of the aortic root are challenging to manage and unceasing bleeding hampers adequate visualisation for performing repair. We report a case of a 31-year-old male that presented to the emergency department 1 h after sustaining a stab wound injury within proximity of the left upper sternal border. Vital signs were stable on presentation. Physical examination revealed a 1.5 cm laceration in the 3rd intercostal space. Chest X-ray revealed a small left pneumothorax, FAST scan was negative, and CT of the chest revealed left sided haemopneumothorax and haemopericardium. The patient was emergently transferred to the operating room where median thoracotomy was performed. A significant amount of bleeding was observed originating from a 1 cm laceration of the aortic root. Bleeding was controlled using a Foley catheter after unsuccessful attempts of digital compression, and the laceration was repaired using pledgeted sutures. Postoperative echocardiography and CT scan of the chest revealed normal cardiac functions with resolution of haemopericardium and haemopneumothorax, and the patient was discharged in a stable condition. High index of suspicion should be maintained for injury to the great vessels in patients with penetrating chest injuries, despite apparent haemodynamic stability. In this case, balloon tamponade using a Foley catheter served as a quick and simple technique that resulted in an almost bloodless field, facilitating adequate visualisation for definitive repair. Although the use of this technique has been previously described, this report serves as a reminder that a Foley catheter can be successfully used for balloon catheter tamponade in injuries to the aortic root. Keywords: Aortic root, Injury, Foley's catheter, Balloon catheter, Aorta

Comparative in vivo analysis of the role of the adventitia and the endothelium on arterial mechanical function: relevance for aortic counterpulsation.

Science.gov (United States)

Bia, Daniel; Zócalo, Yanina; Wray, Sandra; Cabrera-Fischer, Edmundo I

2017-06-09

The comparative effect of the intimal and adventitial layers on arterial biomechanics control, in basal and altered conditions, remains to be elucidated. This study aimed (1) to characterize the arterial conduit (CF) and buffering (distensibility) function of the iliac arteries in in vivo animals, in which the intimal and adventitial layers were removed; (2) to determine the effects of intra-aortic ballon pumping (IABP) on simultaneously de-adventitialized (DA) and de-endothelialized (DE) iliac arteries before and after induced heart failure. Pressure and diameter signals were measured in the iliac arteries of sheep (n = 7) in which the adventitial and intima layer were removed. Intra-aortic balloon pump (IABP) assistance was used in a control state and after heart failure induction. Both DE and DA determined significant changes in arterial diameter, distensibility and CF. Changes were higher after DA than after DE in terms of distensibility and CF (p<0.05). DA followed by DE (DA + DE) showed significant increases in arterial diameter and CF, accompanied by a decrease in distensibility (p<0.05) with respect to intact arteries. Heart failure induction caused significant hemodynamic changes without modifying the already impaired local biomechanical parameters. Nonsignificant improvements in the biomechanical parameters of DA + DE iliac arteries were observed during IABP before and after heart failure induction. Biomechanical changes caused by DA of iliac arteries were more important than those observed after DE. The DA + DE arteries showed significant differences with respect to intact arteries and with DA or DE arteries. IABP-related effects on arterial mechanics were absent in DA + DE arteries.

Satisfactory short-term outcomes of the STABILISE technique for type B aortic dissection.

Science.gov (United States)

Melissano, Germano; Bertoglio, Luca; Rinaldi, Enrico; Mascia, Daniele; Kahlberg, Andrea; Loschi, Diletta; De Luca, Monica; Monaco, Fabrizio; Chiesa, Roberto

2018-03-29

The aim of this study was to evaluate the perioperative and short-term results in a cohort of patients treated during the last year at our institution with the stent-assisted balloon-induced intimal disruption and relamination in aortic dissection repair (STABILISE) technique for acute complicated aortic dissection. Between June 2016 and June 2017, 10 patients (all male; mean age, 62.6 ± 7.4 years) received treatment for acute complicated aortic dissection with the STABILISE technique. After a standard provisional extension to induce complete attachment procedure using the commercially available endovascular dissection system (Cook Medical, Bloomington, Ind), the distal stent graft area and the bare stent area were ballooned to completely exclude the thoracic false lumen (FL) and to obtain a single-channeled abdominal aorta. Computed tomography was routinely performed within the first postoperative week before discharge and then at 3 months, at 6 months, and yearly thereafter. The technical and clinical success rates were analyzed. The 30-day technical and clinical success rates were 100%, with complete thrombosis of the thoracic FL and no type I endoleak. Malperfusion was resolved in all cases. No aortic ruptures were recorded, and no open conversion was required. One case of delayed spinal cord ischemia fully resolved within the discharge period. Predischarge computed tomography showed complete thrombosis of the thoracic FL in all cases. In two cases, some degree of patency of the abdominal FL was observed. At short-term follow-up, the overall aortic diameters remained stable with no further dilation. The STABILISE technique was safe and feasible in this cohort of patients, with complete thrombosis of the thoracic FL and creation of a single-channeled aorta in most cases. Further studies are needed to ascertain the long-term behavior of the treated aorta. Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Uso rutinario del balón de contra-pulsación aórtica preoperatorio en pacientes con enfermedad del tronco común izquierdo sometidos a cirugía de revascularización coronaria Routine use of preoperative intra-aortic balloon pump counterpulsation (IABP implantation in patients with left main coronary artery disease undergoing coronary revascularization surgery

Directory of Open Access Journals (Sweden)

Andrés Fernández

2008-08-01

cuidados intensivos se infectaron 6,5% de los pacientes con balón y 3% del grupo sin balón (p=0,49 y hubo sepsis en 4,3% del grupo con balón y en ninguno del grupo restante (p=0,23. La letalidad en la unidad de cuidados intensivos se presentó en 2,2% del grupo de balón y en 3% del otro grupo (p=0,06. No ocurrió mortalidad intrahospitalaria fuera de la unidad de cuidados intensivos como tampoco mortalidad a 30 días después del alta. El tiempo de estancia en la misma unidad fue de 4,13 días en el grupo de balón y 2,7 días en el grupo sin balón, sin diferencia estadísticamente significativa entre éstos (p=0,154. El tiempo de ventilación mecánica en el grupo de balón fue de 1,96 días mientras que en el otro grupo fue de 1,18 días sin diferencia estadísticamente significativa (p=0,288. Con respecto a los pacientes que recibieron balón de contra pulsación intra-aórtico, el promedio de uso de balón fue de 1,32 días y no se presentaron complicaciones vasculares relacionadas con su uso. Conclusiones: este estudio sugiere que con el uso rutinario del balón de contra pulsación aórtica previo a la cirugía electiva de revascularización coronaria en pacientes cuya única indicación sea la lesión severa del tronco común izquierdo, no se obtiene beneficio en cuanto a letalidad y tiempo de estancia en la unidad de cuidados intensivos, ni con respecto al tiempo de ventilación mecánica. Tampoco se encontró mayor riesgo de desarrollar infección o sepsis en la misma unidad.Background: Left main coronary artery disease as the only criterion for intra-aortic balloon counterpulsation implantation is an indication which evidence is limited to experts’ recommendations; therefore, studies that may give a higher level of evidence are required. For this reason, we developed in our institution a study that evaluated the experience in the use of IABP in patients with left main coronary artery disease undergoing coronary revascularization surgery. Objective

Aortic intracardiac echocardiography-guided septal puncture during mitral valvuloplasty.

Science.gov (United States)

Akkaya, Emre; Vuruskan, Ertan; Zorlu, Ali; Sincer, Isa; Kucukosmanoglu, Mehmet; Ardic, Idris; Yilmaz, Mehmet Birhan

2014-01-01

Transoesophageal echocardiography (TEE) and venous intracardiac echocardiography (ICE) are traditionally used to visualize the interatrial septum (IAS) and the tenting effect of the fossa ovalis in patients undergoing percutaneous balloon mitral valvuloplasty (PBMV). The aim of the present study was to assess the comparative efficacy and safety of arterial (intra-aortic) ICE and venous ICE, compared with TEE (traditional approach), in the patients undergoing PBMV. TEE, aortic ICE, and venous ICE were consecutively performed in 50 patients (40 ± 9 years, 86% female). The images of intracardiac structures were obtained from both aortic and right atrial loci. The IAS was visualized using TEE, aortic ICE, and venous ICE. The mean mitral valve area was 1.14 ± 0.2 cm(2), and the mean left atrial volume index was 57.5 ± 12 mL/m(2). The mean size of the visualized septal length was 48 ± 5 mm by TEE, 51 ± 5 mm by aortic ICE, and 33 ± 6 mm by venous ICE. The Bland-Altman test indicated that the 95% limits of agreement for the measurement of septal diameter ranged from -11.0 to +5.9 mm (mean -2.5 mm) between TEE and aortic ICE, -2.8 to +33.5 mm (mean +15.3 mm) between TEE and venous ICE, and -36.6 to +0.8 mm (mean -17.9 mm) between venous and aortic ICE. Standard venous ICE generally tended to yield smaller values compared with TEE and aortic ICE for the measurement of septal length. Furthermore, the view of fossa ovalis and 'tenting effect' was optimal in 11 patients on venous ICE; however, the fossa ovalis and tip of the needle were well visualized in all patients on aortic ICE (P < 0.001). There were no major complications with the use of aortic ICE. Aortic ICE is a superior alternative to venous ICE and facilitates trans-septal puncture in patients with mitral stenosis.

A comparison of Selective Aortic Arch Perfusion and Resuscitative Endovascular Balloon Occlusion of the Aorta for the management of hemorrhage-induced traumatic cardiac arrest: A translational model in large swine.

Directory of Open Access Journals (Sweden)

Ed B G Barnard

2017-07-01

Full Text Available Survival rates remain low after hemorrhage-induced traumatic cardiac arrest (TCA. Noncompressible torso hemorrhage (NCTH is a major cause of potentially survivable trauma death. Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA at the thoracic aorta (Zone 1 can limit subdiaphragmatic blood loss and allow for IV fluid resuscitation when intrinsic cardiac activity is still present. Selective Aortic Arch Perfusion (SAAP combines thoracic aortic balloon hemorrhage control with intra-aortic oxygenated perfusion to achieve return of spontaneous circulation (ROSC when cardiac arrest has occurred.Male Yorkshire Landrace cross swine (80.0 ± 6.0 kg underwent anesthesia, instrumentation for monitoring, and splenectomy. TCA was induced by laparoscopic liver lobe resection combined with arterial catheter blood withdrawal to achieve a sustained systolic blood pressure <10 mmHg, cardiac arrest. After 3 min of arrest, swine were allocated to one of three interventions: (1 REBOA plus 4 units of IV fresh whole blood (FWB, (2 SAAP with oxygenated lactated Ringer's (LR, 1,600 mL/2 min, or (3 SAAP with oxygenated FWB 1,600 mL/2 min. Primary endpoint was survival to the end of 60 min of resuscitation, a simulated prehospital phase. Thirty animals were allocated to 3 groups (10 per group-5 protocol exclusions resulted in a total of 35 animals being used. Baseline measurements and time to cardiac arrest were not different amongst groups. ROSC was achieved in 0/10 (0%, 95% CI 0.00-30.9 REBOA, 6/10 (60%, 95% CI 26.2-87.8 SAAP-LR and 10/10 (100%, 95% CI 69.2-100.0 SAAP-FWB animals, p < 0.001. Survival to end of simulated 60-minute prehospital resuscitation was 0/10 (0%, 95% CI 0.00-30.9 for REBOA, 1/10 (10%, 95% CI 0.25-44.5 for SAAP-LR and 9/10 (90%, 95% CI 55.5-99.7 for SAAP-FWB, p < 0.001. Total FWB infusion volume was similar for REBOA (2,452 ± 0 mL and SAAP-FWB (2,250 ± 594 mL. This study was undertaken in laboratory conditions, and as such may have

Application of new balloon catheters in the treatment of congenital heart defects

Directory of Open Access Journals (Sweden)

Roland Fiszer

2016-08-01

Full Text Available Introduction : Balloon angioplasty (BAP and aortic or pulmonary balloon valvuloplasty (BAV, BPV are well-established treatment options in congenital heart defects. Recently, significant technological progress has been made and new catheters have been implemented in clinical practice. Aim: To analyze the results of BAP, BAV and BPV with the new balloon catheter Valver and its second generation Valver II, which the company Balton (Poland launched and developed. These catheters have not been clinically evaluated yet. Material and methods: We performed 64 interventions with Valver I and Valver II. With Valver I the following procedures were performed: 17 BPV (including 9 in tetralogy of Fallot – TOF, 10 BAV and 27 BAP in coarctations of the aorta (CoA – including 9 native and 18 after surgery. With Valver II ten interventions were done – 3 BPV, 2 pulmonary supravalvular BAP (after switch operations, 2 BAP of recoarctations and 3 other BAP. Age of the patients ranged from a few days to 40 years. Results: All procedures were completed successfully, without rupture of any balloon catheters. The pressure gradient drop was statistically significant in all groups: BPV in isolated pulmonary valvular stenosis 28.1 mm Hg (mean, BPV in TOF 18.7 mm Hg, BAV 32.8 mm Hg, BAP in native CoA 15.4 mm Hg and in recoarctations 18.6 mm Hg. In 3 cases during rapid deflation of Valver I, wrinkles of the balloons made it impossible to insert the whole balloon into the vascular sheath (all were removed surgically from the groin. No such complication occured with Valver II. Conclusions : Valver balloon catheters are an effective treatment modality in different valvular and vascular stenoses.

The impact of aortic manipulation on neurologic outcomes after coronary artery bypass surgery: a risk-adjusted study.

Science.gov (United States)

Kapetanakis, Emmanouil I; Stamou, Sotiris C; Dullum, Mercedes K C; Hill, Peter C; Haile, Elizabeth; Boyce, Steven W; Bafi, Ammar S; Petro, Kathleen R; Corso, Paul J

2004-11-01

Cerebral embolization of atherosclerotic plaque debris caused by aortic manipulation during conventional coronary artery bypass grafting (CABG) is a major mechanism of postoperative cerebrovascular accidents (CVA). Off-pump CABG (OPCABG) reduces stroke rates by minimizing aortic manipulation. Consequently, the effect of different levels of aortic manipulation on neurologic outcomes after CABG surgery was examined. From January 1998 to June 2002, 7,272 patients underwent isolated CABG surgery through three levels of aortic manipulation: full plus tangential (side-biting) aortic clamp application (on-pump surgery; n = 4,269), only tangential aortic clamp application (OPCABG surgery; n = 2,527) or an "aortic no-touch" technique (OPCABG surgery; n = 476). A risk-adjusted logistic regression analysis was performed to establish the likelihood of postoperative stroke with each technique. Preoperative risk factors for stroke from the literature, and those found significant in a univariable model were used. A significant association for postoperative stroke correspondingly increasing with the extent of aortic manipulation was demonstrated by the univariable analysis (CVA incidence respectively increasing from 0.8% to 1.6% to a maximum of 2.2%, p < 0.01). In the logistic regression model, patients who had a full and a tangential aortic clamp applied were 1.8 times more likely to have a stroke versus those without any aortic manipulation (95% confidence interval: 1.15 to 2.74, p < 0.01) and 1.7 times more likely to develop a postoperative stroke than those with only a tangential aortic clamp applied (95% confidence interval: 1.11 to 2.48, p < 0.01). Aortic manipulation during CABG is a contributing mechanism for postoperative stroke. The incidence of postoperative stroke increases with increased levels of aortic manipulation.

Balloon-Occluded Carbon Dioxide Gas Angiography for Internal Iliac Arteriography and Intervention.

Science.gov (United States)

Kishino, Mitsuhiro; Nakaminato, Shuichiro; Kitazume, Yoshio; Miyasaka, Naoyuki; Kudo, Toshifumi; Saida, Yukihisa; Tateishi, Ukihide

2018-07-01

The usefulness of carbon dioxide (CO 2 ) gas digital subtraction angiography (DSA) has been reported for patients with renal insufficiency and allergy to iodinated contrast agents. However, CO 2 gas cannot replace the iodinated contrast agent in all cases owing to some disadvantages. We describe balloon-occluded CO 2 DSA (B-CO 2 DSA) as an improved CO 2 DSA procedure for interventions in the internal iliac artery (IIA) region and compare the quality of images obtained using conventional CO 2 DSA and B-CO 2 DSA. B-CO 2 DSA-guided embolization was performed for one case of genital bleeding with an acute anaphylactic reaction to the iodinated contrast agent and for three cases of type II endoleaks after endovascular abdominal aortic aneurysm repair with renal dysfunction. A 9-mm occlusion balloon catheter was placed just after the orifice of the IIA. Then, 10-15 ml of CO 2 gas was injected manually via the catheter with and without balloon occlusion. The quality of sequential digital subtraction angiograms was analyzed based on a scoring criterion. In all four cases, image quality was improved with B-CO 2 DSA; the poor quality of images without balloon occlusion was because of reflux of the CO 2 gas. B-CO 2 DSA improves the image quality of CO 2 DSA in the IIA region and is useful for vascular intervention. Level IV.

Updated clinical indications for transcatheter aortic valve implantation in patients with severe aortic stenosis: expert opinion of the Italian Society of Cardiology and GISE.

Science.gov (United States)

Indolfi, Ciro; Bartorelli, Antonio L; Berti, Sergio; Golino, Paolo; Esposito, Giovanni; Musumeci, Giuseppe; Petronio, Sonia; Tamburino, Corrado; Tarantini, Giuseppe; Ussia, Gianpaolo; Vassanelli, Corrado; Spaccarotella, Carmen; Violini, Roberto; Mercuro, Giuseppe; Romeo, Francesco

2018-05-01

: The introduction of percutaneous treatment of severe aortic stenosis with transcatheter aortic valve implantation (TAVI) remains one of the greatest achievements of interventional cardiology. In fact, TAVI emerged as a better option than either medical therapy or balloon aortic valvuloplasty for patients who cannot undergo surgical aortic valve replacement (SAVR) or are at high surgical risk. Recently, increased operator experience and improved device systems have led to a worldwide trend toward the extension of TAVI to low-risk or intermediate-risk patients. In this expert opinion paper, we first discuss the basic pathophysiology of aortic stenosis in different settings then the key results of recent clinical investigations on TAVI in intermediate-risk aortic stenosis patients are summarized. Particular emphasis is placed on the results of the nordic aortic valve intervention, placement of aortic transcatheter valves (PARTNER) 2 and Surgical Replacement and Transcatheter Aortic Valve Implantation Randomized trials. The PARTNER 2 was the first large randomized trial that evaluated the outcome of TAVI in patients at intermediate risk. The PARTNER 2 data demonstrated that TAVI is a feasible and reasonable alternative to surgery in intermediate-risk patients (Society of Thoracic Surgeons 4-8%), especially if they are elderly or frail. There was a significant interaction between TAVI approach and mortality, with transfemoral TAVI showing superiority over SAVR. Moreover, we examine the complementary results of the recently concluded Surgical Replacement and Transcatheter Aortic Valve Implantation trial. This prospective randomized trial demonstrated that TAVI is comparable with surgery (primary end point 12.6% in the TAVI group vs. 14.0% in the SAVR group) in severe aortic stenosis patients deemed to be at intermediate risk. We review the most relevant clinical evidence deriving from nonrandomized studies and meta-analyses. Altogether, clinical outcome available data

Suprarenal fixation resulting in intestinal malperfusion after endovascular aortic aneurysm repair.

Science.gov (United States)

Siani, Andrea; Accrocca, Federico; De Vivo, Gennaro; Marcucci, Giustino

2016-05-01

Superior mesenteric artery (SMA) and coeliac axis (CA) occlusion after endovascular abdominal aneurysm aortic repair (EVAR-AAA), using endograft with suprarenal fixation, are uncommon. However, we are reporting a case of visceral malperfusion, which occurred 7 days after successful EVAR with suprarenal fixation for symptomatic AAA. Endograft metal stent barbs caused severe stenosis of SMA and CA. A successful recovery of SMA was carried out by means of a balloon-expandable stent released through bare metal stent barbs. We believe that an unfavourable anatomy of a proximal aortic neck and visceral aorta may have caused a wrong stent strut deployment with the coverage of CA and SMA. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

CT-angiography-based evaluation of the aortic annulus for prosthesis sizing in transcatheter aortic valve implantation (TAVI)-predictive value and optimal thresholds for major anatomic parameters.

Science.gov (United States)

Schwarz, Florian; Lange, Philipp; Zinsser, Dominik; Greif, Martin; Boekstegers, Peter; Schmitz, Christoph; Reiser, Maximilian F; Kupatt, Christian; Becker, Hans C

2014-01-01

To evaluate the predictive value of CT-derived measurements of the aortic annulus for prosthesis sizing in transcatheter aortic valve implantation (TAVI) and to calculate optimal cutoff values for the selection of various prosthesis sizes. The local IRB waived approval for this single-center retrospective analysis. Of 441 consecutive TAVI-patients, 90 were excluded (death within 30 days: 13; more than mild aortic regurgitation: 10; other reasons: 67). In the remaining 351 patients, the CoreValve (Medtronic) and the Edwards Sapien XT valve (Edwards Lifesciences) were implanted in 235 and 116 patients. Optimal prosthesis size was determined during TAVI by inflation of a balloon catheter at the aortic annulus. All patients had undergone CT-angiography of the heart or body trunk prior to TAVI. Using these datasets, the diameter of the long and short axis as well as the circumference and the area of the aortic annulus were measured. Multi-Class Receiver-Operator-Curve analyses were used to determine the predictive value of all variables and to define optimal cutoff-values. Differences between patients who underwent implantation of the small, medium or large prosthesis were significant for all except the large vs. medium CoreValve (all p'sprosthesis size for both manufacturers (multi-class AUC's: 0.80, 0.88, 0.91, 0.88, 0.88, 0.89). Using the calculated optimal cutoff-values, prosthesis size is predicted correctly in 85% of cases. CT-based aortic root measurements permit excellent prediction of the prosthesis size considered optimal during TAVI.

The German Aortic Valve Registry (GARY): a nationwide registry for patients undergoing invasive therapy for severe aortic valve stenosis.

Science.gov (United States)

Beckmann, A; Hamm, C; Figulla, H R; Cremer, J; Kuck, K H; Lange, R; Zahn, R; Sack, S; Schuler, G C; Walther, T; Beyersdorf, F; Böhm, M; Heusch, G; Funkat, A K; Meinertz, T; Neumann, T; Papoutsis, K; Schneider, S; Welz, A; Mohr, F W

2012-07-01

Background The increasing prevalence of severe aortic valve defects correlates with the increase of life expectancy. For decades, surgical aortic valve replacement (AVR), under the use of extracorporeal circulation, has been the gold standard for treatment of severe aortic valve diseases. In Germany ~12,000 patients receive isolated aortic valve surgery per year. For some time, percutaneous balloon valvuloplasty has been used as a palliative therapeutic option for very few patients. Currently, alternatives for the established surgical procedures such as transcatheter aortic valve implantation (TAVI) have become available, but there are only limited data from randomized studies or low-volume registries concerning long-time outcome. In Germany, the implementation of this new technology into hospital care increased rapidly in the past few years. Therefore, the German Aortic Valve Registry (GARY) was founded in July 2010 including all available therapeutic options and providing data from a large quantity of patients.Methods The GARY is assembled as a complete survey for all invasive therapies in patients with relevant aortic valve diseases. It evaluates the new therapeutic options and compares them to surgical AVR. The model for data acquisition is based on three data sources: source I, the mandatory German database for external performance measurement; source II, a specific registry dataset; and source III, a follow-up data sheet (generated by phone interview). Various procedures will be compared concerning observed complications, mortality, and quality of life up to 5 years after the initial procedure. Furthermore, the registry will enable a compilation of evidence-based indication criteria and, in addition, also a comparison of all approved operative procedures, such as Ross or David procedures, and the use of different mechanical or biological aortic valve prostheses.Results Since the launch of data acquisition in July 2010, almost all institutions performing

Type A Aortic Dissection Presenting with Inferior ST-Elevation Myocardial Infarction.

Science.gov (United States)

Wu, Bao-Tzung; Li, Chun-Yi; Chen, Ying-Tsung

2014-05-01

Type A aortic dissection with concurrent ST-elevation myocardial infarction (STEMI) is relatively rare. However, it can be potentially fatal and easily misdiagnosed as STEMI alone. Misdiagnosis will lead to inappropriate administration of anticoagulant and thrombolytic therapy and delayed surgical repair of the aorta. In patients with STEMI, short reperfusion time is associated with improved survival, and minimizing the door-to-balloon time is the goal of therapy worldwide. However, signs critical for differential diagnosis may be overlooked in the rush to primary percutaneous coronary intervention. When a patient is encountered who presents with chest pain and ST elevation on electrocardiogram, STEMI should not be the only diagnosis considered. By using bedside available information, detailed history taking and focused physical examination, it is possible to avoid a mistaken diagnosis. Here we report a case of Stanford type A aortic dissection with STEMI that was initially misdiagnosed as sole acute inferior wall myocardial infarction. Patient mortality may have resulted from delayed diagnosis and surgical treatment. Acute myocardial infarction; Aortic dissection.

Open-heart surgery using a centrifugal pump: a case of hereditary spherocytosis.

Science.gov (United States)

Matsuzaki, Yuichi; Tomioka, Hideyuki; Saso, Masaki; Azuma, Takashi; Saito, Satoshi; Aomi, Shigeyuki; Yamazaki, Kenji

2016-08-26

Hereditary spherocytosis is a genetic, frequently familial hemolytic blood disease characterized by varying degrees of hemolytic anemia, splenomegaly, and jaundice. There are few reports on adult open-heart surgery for patients with hereditary spherocytosis. We report a rare case of an adult open-heart surgery associated with hereditary spherocytosis. A 63-year-old man was admitted for congestive heart failure due to bicuspid aortic valve, aortic valve regurgitation, and sinus of subaortic aneurysm. The family history, the microscopic findings of the blood smear, and the characteristic osmotic fragility confirmed the diagnosis of hereditary spherocytosis. Furthermore, splenectomy had not been undertaken preoperatively. The patient underwent a successful operation by means of a centrifugal pump. Haptoglobin was used during the cardiopulmonary bypass, and a biological valve was selected to prevent hemolysis. No significant hemolysis occurred intraoperatively or postoperatively. There are no previous reports of patients with hereditary spherocytosis, and bicuspid aortic valve. We have successfully performed an adult open-heart surgery using a centrifugal pump in an adult patient suffering from hereditary spherocytosis and bicuspid aortic valve.

Supra-annular structure assessment for self-expanding transcatheter heart valve size selection in patients with bicuspid aortic valve.

Science.gov (United States)

Liu, Xianbao; He, Yuxin; Zhu, Qifeng; Gao, Feng; He, Wei; Yu, Lei; Zhou, Qijing; Kong, Minjian; Wang, Jian'an

2018-04-01

To explore assessment of supra-annular structure for self-expanding transcatheter heart valve (THV) size selection in patients with bicuspid aortic stenosis (AS). Annulus-based device selection from CT measurement is the standard sizing strategy for tricuspid aortic valve before transcatheter aortic valve replacement (TAVR). Because of supra-annular deformity, device selection for bicuspid AS has not been systemically studied. Twelve patients with bicuspid AS who underwent TAVR with self-expanding THVs were included in this study. To assess supra-annular structure, sequential balloon aortic valvuloplasty was performed in every 2 mm increments until waist sign occurred with less than mild regurgitation. Procedural results and 30 day follow-up outcomes were analyzed. Seven patients (58.3%) with 18 mm; three patients (25%) with sequential 18 mm, 20 mm; and only two patients (16.7%) with sequential 18 mm, 20 mm, and 22 mm balloon sizing were performed, respectively. According to the results of supra-annular assessment, a smaller device size (91.7%) was selected in all but one patient compared with annulus based sizing strategy, and the outcomes were satisfactory with 100% procedural success. No mortality and 1 minor stroke were observed at 30 d follow-up. The percentage of NYHA III/IV decreased from 83.3% (9/12) to 16.7% (2/12). No new permanent pacemaker implantation and no moderate or severe paravalvular leakage were found. A supra-annular structure based sizing strategy is feasible for TAVR in patients with bicuspid AS. © 2018 The Authors Catheterization and Cardiovascular Interventions Published by Wiley Periodicals, Inc.

Innovative chimney-graft technique for endovascular repair of a pararenal abdominal aortic aneurysm.

Science.gov (United States)

Galiñanes, Edgar Luis; Hernandez-Vila, Eduardo A; Krajcer, Zvonimir

2015-02-01

After abdominal aortic aneurysm repair, progressive degeneration of the aneurysm can be challenging to treat. Multiple comorbidities and previous operations place such patients at high risk for repeat surgery. Endovascular repair is a possible alternative; however, challenging anatomy can push the limits of available technology. We describe the case of a 71-year-old man who presented with a 5.3-cm pararenal aneurysm 4 years after undergoing open abdominal aortic aneurysm repair. To avoid reoperation, we excluded the aneurysm by endovascular means, using visceral-artery stenting, a chimney-graft technique. Low-profile balloons on a monorail system enabled the rapid exchange of coronary wires via a buddy-wire technique. This novel approach facilitated stenting and simultaneous angioplasty of multiple visceral vessels and the abdominal aorta.

Comparison of two doses of heparin on outcome in off-pump coronary artery bypass surgery patients: A prospective randomized control study

Directory of Open Access Journals (Sweden)

Murali Chakravarthy

2017-01-01

Full Text Available Introduction: While off pump coronary artery bypass surgery is practiced with an intention to reduce the morbidity associated with cardiopulmonary bypass, the resultant ′hypercoagulability′ needs to be addressed. Complications such as cavitary thrombus possibly due to the hyper coagulability after off pump coronary artery bypass surgery have been described. Many clinicians use higher doses of heparin - up to 5 mg/kg in order to thwart this fear. Overall, there appears to be no consensus on the dose of heparin in off pump coronary artery bypass surgeries. Aim of the Study: The aim of the study was understand the differences in outcome of such as transfusion requirement, myocardial ischemia, and morbidity when two different doses were used for systemic heparinization. Methods: Elective patients scheduled for off pump coronary artery bypass surgery were included. Ongoing anti platelet medication was not an exclusion criteria, however, anti platelet medications were ceased about a week prior to surgery when possible. Thoracic epidural anesthesia was administered as an adjunct in patients who qualified for it. By computer generated randomization chart, patients were chosen to receive either 2 or 3 mg/kg of intravenous unfractioned heparin to achieve systemic heparinization with activated clotting time targeted at >240 secs. Intraoperative blood loss, postoperative blood loss, myocardial ischemic episodes, requirement of intraaortic balloon counter pulsation and transfusion requirement were analyzed. Results: Sixty two patients participated in the study. There was one conversion to cardiopulmonary bypass. The groups had comparable ACT at baseline (138.8 vs. 146.64 seconds, P = 0.12; 3 mg/kg group had significantly higher values after heparin, as expected. But after reversal with protamine, ACT and need for additional protamine was similar among the groups. Intraoperative (685.56 ± 241.42 ml vs. 675.15 ± 251.86 ml, P = 0.82 and postoperative

CT-angiography-based evaluation of the aortic annulus for prosthesis sizing in transcatheter aortic valve implantation (TAVI-predictive value and optimal thresholds for major anatomic parameters.

Directory of Open Access Journals (Sweden)

Florian Schwarz

Full Text Available BACKGROUND/OBJECTIVES: To evaluate the predictive value of CT-derived measurements of the aortic annulus for prosthesis sizing in transcatheter aortic valve implantation (TAVI and to calculate optimal cutoff values for the selection of various prosthesis sizes. METHODS: The local IRB waived approval for this single-center retrospective analysis. Of 441 consecutive TAVI-patients, 90 were excluded (death within 30 days: 13; more than mild aortic regurgitation: 10; other reasons: 67. In the remaining 351 patients, the CoreValve (Medtronic and the Edwards Sapien XT valve (Edwards Lifesciences were implanted in 235 and 116 patients. Optimal prosthesis size was determined during TAVI by inflation of a balloon catheter at the aortic annulus. All patients had undergone CT-angiography of the heart or body trunk prior to TAVI. Using these datasets, the diameter of the long and short axis as well as the circumference and the area of the aortic annulus were measured. Multi-Class Receiver-Operator-Curve analyses were used to determine the predictive value of all variables and to define optimal cutoff-values. RESULTS: Differences between patients who underwent implantation of the small, medium or large prosthesis were significant for all except the large vs. medium CoreValve (all p's<0.05. Furthermore, mean diameter, annulus area and circumference had equally high predictive value for prosthesis size for both manufacturers (multi-class AUC's: 0.80, 0.88, 0.91, 0.88, 0.88, 0.89. Using the calculated optimal cutoff-values, prosthesis size is predicted correctly in 85% of cases. CONCLUSION: CT-based aortic root measurements permit excellent prediction of the prosthesis size considered optimal during TAVI.

Rapid Two-stage Versus One-stage Surgical Repair of Interrupted Aortic Arch with Ventricular Septal Defect in Neonates

Directory of Open Access Journals (Sweden)

Meng-Lin Lee

2008-11-01

Conclusion: The outcome of rapid two-stage repair is comparable to that of one-stage repair. Rapid two-stage repair has the advantages of significantly shorter cardiopulmonary bypass duration and AXC time, and avoids deep hypothermic circulatory arrest. LVOTO remains an unresolved issue, and postoperative aortic arch restenosis can be dilated effectively by percutaneous balloon angioplasty.

Defining degree of aortic occlusion for partial-REBOA: A computed tomography study on large animals.

Science.gov (United States)

Reva, Viktor A; Matsumura, Yosuke; Samokhvalov, Igor M; Pochtarnik, Alexander A; Zheleznyak, Igor S; Mikhailovskaya, Ekaterina M; Morrison, Jonathan J

2018-04-20

Partial resuscitative endovascular balloon occlusion of the aorta (P-REBOA) is a modified REBOA technique designed to help ameliorate ischemia-reperfusion injury. The balloon is partially deflated, allowing a proportion of aortic flow distal to the balloon. The aim of this study is to use an ovine model of haemorrhagic shock to correlate the degree of occlusion to several hemodynamic indices. Six sheep weighing 35-46 kg underwent a controlled venous haemorrhage inside a CT scanner until the systolic arterial pressure (AP) dropped to fashion (proximal: r 2  = 0.85, p trend (r 2  = 0.90, p < 0.001). The relationship between percentage occlusion and IBP was sigmoid. MAP values became significantly different at 40-49% occlusion and more (p < 0.01). Furthermore, a drop in the distal pulse pressure from 7.0 (5.5-16.5) to 2.0 (1.5-5.0) mmHg was observed at 80% occlusion. All animals had femoral pulse pressure <5 mmHg at 80% of occlusion and more, which also coincided with the observed loss of pulsatility of the femoral wave-form. Serial CT angiography at an ovine model of haemorrhagic shock demonstrates a correlation between the femoral MAP, F/C pressure gradient and degree of zone I P-REBOA during the staged partial aortic occlusion. These parameters should be considered potential parameters to define the degree of P-REBOA during animal research and clinical practice. Copyright © 2018 Elsevier Ltd. All rights reserved.

A new approach to the diagnosis of esophageal rupture due to balloon dilatation

International Nuclear Information System (INIS)

Song, Ho Young; Han, Young Min; Lee, Sang Young; Kuh, Ja Hong; Lee, Dong Kun; Chae, Soo Wan

1990-01-01

The diagnosis of esophageal rupture in balloon dilatation is usually made from clinical symptom of sharp chest pain, plain chest radiographs and esophagograms after dilation. It has some problems; the pain is varied patients to patients and bacterial flora in the mouth or esophagus can be mixed with the contrast media to flow into the mediastinum during esophagography, to create mediastinitis. We could make the diagnosis of esophageal rupture without using contrast media by the observation of the pressure change in the balloon during dilatation. An infusion pump, transducer and esophageal balloon were connected through a multi-way connector, and the transducer of them was also connected to an amplifier which was connected to a pressure monitor to record the balloon pressure. As balloon(20mm/3cm) inserted in the mid-thoracic esophagus under the fluoroscopic control was inflated until the esophagus was ruptured. Balloon was distended by injecting air in 15 rabbits(A group), and by injecting diluted contrast medium in 15 rabbits(B group). The pressure decrease after esophageal rupture was ranged from 94 to 160 mmHg(mean; 103) in A group and 340 to 1040 mmHg(mean; 537) in B group. The pressure curve of A group was smooth, regular and so accurate to make the diagnosis of esophageal rupture, whereas that of B group was irregular and not so accurate. In conclusion, our new method to make the diagnosis of esophageal rupture during balloon dilatation may be useful in patients of esophageal stricture

Selective Heart, Brain and Body Perfusion in Open Aortic Arch Replacement.

Science.gov (United States)

Maier, Sven; Kari, Fabian; Rylski, Bartosz; Siepe, Matthias; Benk, Christoph; Beyersdorf, Friedhelm

2016-09-01

Open aortic arch replacement is a complex and challenging procedure, especially in post dissection aneurysms and in redo procedures after previous surgery of the ascending aorta or aortic root. We report our experience with the simultaneous selective perfusion of heart, brain, and remaining body to ensure optimal perfusion and to minimize perfusion-related risks during these procedures. We used a specially configured heart-lung machine with a centrifugal pump as arterial pump and an additional roller pump for the selective cerebral perfusion. Initial arterial cannulation is achieved via femoral artery or right axillary artery. After lower body circulatory arrest and selective antegrade cerebral perfusion for the distal arch anastomosis, we started selective lower body perfusion simultaneously to the selective antegrade cerebral perfusion and heart perfusion. Eighteen patients were successfully treated with this perfusion strategy from October 2012 to November 2015. No complications related to the heart-lung machine and the cannulation occurred during the procedures. Mean cardiopulmonary bypass time was 239 ± 33 minutes, the simultaneous selective perfusion of brain, heart, and remaining body lasted 55 ± 23 minutes. One patient suffered temporary neurological deficit that resolved completely during intensive care unit stay. No patient experienced a permanent neurological deficit or end-organ dysfunction. These high-risk procedures require a concept with a special setup of the heart-lung machine. Our perfusion strategy for aortic arch replacement ensures a selective perfusion of heart, brain, and lower body during this complex procedure and we observed excellent outcomes in this small series. This perfusion strategy is also applicable for redo procedures.

Impact of around-the-clock in-house cardiology fellow coverage on door-to-balloon time in an academic medical center

Directory of Open Access Journals (Sweden)

Kohan LC

2017-04-01

Full Text Available Luke C Kohan,1,* Vijaiganesh Nagarajan,1,* Michael A Millard,2 Michael J Loguidice,2 Nancy M Fauber,1 Ellen C Keeley1 1Division of Cardiology, 2Department of Medicine, University of Virginia, Charlottesville, VA, USA * These authors contributed equally to this work Objectives: To assess if a change in our cardiology fellowship program impacted our ST elevation myocardial infarction (STEMI program. Background: Fellows covering the cardiac care unit were spending excessive hours in the hospital while on call, resulting in increased duty hours violations. A night float fellow system was started on July 1, 2012, allowing the cardiac care unit fellow to sign out to a night float fellow at 5:30 pm. The night float fellow remained in-house until the morning. Methods: We performed a retrospective study assessing symptom onset to arrival, arterial access to first device, and door-to-balloon (D2B times, in consecutive STEMI patients presenting to our emergency department before and after initiation of the night float fellow system. Results: From 2009 to 2013, 208 STEMI patients presented to our emergency department and underwent primary percutaneous coronary intervention. There was no difference in symptom onset to arrival (150±102 minutes vs 154±122 minutes, p=0.758, arterial access to first device (12±8 minutes vs 11±7 minutes, p=0.230, or D2B times (50±32 minutes vs 52±34 minutes, p=0.681 during regular working hours. However, there was a significant decrease in D2B times seen during off-hours (72±33 minutes vs 49±15 minutes, p=0.007. There was no difference in in-hospital mortality (11% vs 8%, p=0.484 or need for intra-aortic balloon pump placement (7% vs 8%, p=0.793. Conclusion: In academic medical centers, in-house cardiology fellow coverage during off-hours may expedite care of STEMI patients. Keywords: door-to-balloon time, 24/7 in-house call, cardiology fellow

Design and principle of operation of the HeartMate PHP (percutaneous heart pump)

NARCIS (Netherlands)

Mieghem, N.M. van; Daemen, J.; Uil, C. den; Dur, O.; Joziasse, L.; Maugenest, A.M.; Fitzgerald, K.; Parker, C.; Muller, P.; Geuns, R.J.M. van

2018-01-01

The HeartMate PHP (percutaneous heart pump) is a second-generation transcatheter axial flow circulatory support system. The collapsible catheter pump is inserted through a 14 Fr sheath, deployed across the aortic valve expanding to 24 Fr and able to deliver up to 5 L/min blood flow at minimum

Retroperitoneal aortic hemorrhage caused by penetration of an endovascular stent-graft anchoring barb.

Science.gov (United States)

Twine, Christopher P; Winterbottom, Andrew; Shaida, Nadeem; Boyle, Jonathan R

2013-08-01

To report a rare case of acute intraoperative retroperitoneal hemorrhage secondary to aortic penetration by the suprarenal anchoring barb on a stent-graft. A 75-year-old patient on dual antiplatelet therapy for coronary stents and low-molecular-weight heparin for atrial thrombus underwent elective endovascular repair of a 6.7-cm infrarenal abdominal aortic aneurysm. A device with suprarenal fixation and metal anchoring barbs was implanted, and a molding balloon was used that at no time covered the proximal bare metal stents or barbs. In recovery, the patient became tachycardic and hypotensive. After resuscitation, imaging identified an anterior barb penetrating the aortic wall, causing the acute retroperitoneal hemorrhage. A decision to treat conservatively rather than resort to open surgery was difficult but ultimately influenced by the patients' high risk for open surgery. The patient was treated by aggressive reversal of heparin and platelet transfusion, and the bleed settled spontaneously. Major surgery and subsequent morbidity may be avoided by medical management of what would appear to be a surgical problem.

Impact of Aortic Insufficiency on Ascending Aortic Dilatation and Adverse Aortic Events After Isolated Aortic Valve Replacement in Patients With a Bicuspid Aortic Valve.

Science.gov (United States)

Wang, Yongshi; Wu, Boting; Li, Jun; Dong, Lili; Wang, Chunsheng; Shu, Xianhong

2016-05-01

Aberrant flow pattern and congenital fragility bestows bicuspid aortic valve (BAV) with a propensity toward ascending aorta dilatation, aneurysm, and dissection. Whether isolated aortic valve replacement (AVR) can prevent further dilatation in BAV ascending aorta and what indicates concurrent aortic intervention in the case of valve operation remain controversial. From June 2006 to January 2009, patients with a BAV who underwent isolated AVR were consecutively included and categorized into aortic insufficiency (BAV-AI, n = 84) and aortic stenosis (n = 112) groups, and another population of patients with a tricuspid aortic valve with aortic insufficiency (n = 149) was also recruited during the same period for comparison of annual aortic dilatation rate and adverse aortic events after isolated AVR. With a median follow-up period of 72 months (interquartile range, 66 to 78 months), ascending aorta dilatation rates were faster in the BAV-AI group than the BAV plus aortic stenosis and tricuspid aortic valve with aortic insufficiency groups (both p regression analysis identified aortic insufficiency (hazard ratio, 3.7; 95% confidence interval, 1.2 to 11.1; p = 0.019) as an independent risk factor for adverse aortic events among patients with BAV in general, whereas preoperative ascending aortic diameter larger than 45 mm (hazard ratio, 13.8; 95% confidence interval, 3.0 to 63.3; p = 0.001) served as a prognostic indicator in the BAV-AI group. An aggressive policy of preventive aortic interventions seemed appropriate in patients with BAV-AI during AVR, and BAV phenotype presenting as either insufficiency or stenosis should be taken into consideration when contemplating optimal surgical strategies for BAV aortopathy. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

GHOST balloons around Antarctica

Science.gov (United States)

Stearns, Charles R.

1988-01-01

The GHOST balloon position as a function of time data shows that the atmospheric circulation around the Antarctic Continent at the 100 mb and 200 mb levels is complex. The GHOST balloons supposedly follow the horizontal trajectory of the air at the balloon level. The position of GHOST balloon 98Q for a three month period in 1968 is shown. The balloon moved to within 2 deg of the South Pole on 1 October 1968 and then by 9 December 1968 was 35 deg from the South Pole and close to its position on 1 September 1968. The balloon generally moved from west to east but on two occasions moved in the opposite direction for a few days. The latitude of GHOST balloons 98Q and 149Z which was at 200 mb is given. Both balloons tended to get closer to the South Pole in September and October. Other GHOST balloons at the same pressure and time period may not indicate similar behavior.

Gender differences in left ventricular function in patients with isolated aortic stenosis.

Science.gov (United States)

Favero, Luca; Giordan, Massimo; Tarantini, Giuseppe; Ramondo, Angelo Bruno; Cardaioli, Paolo; Isabella, Giambattista; Chioin, Raffaello; Lupia, Mario; Razzolini, Renato

2003-05-01

Hypertrophic response of the left ventricle to systolic overload in aortic stenosis appears to be gender-dependent. To examine gender-related differences in left ventricular (LV) function in patients with isolated severe aortic stenosis, 145 patients (65 women, 80 men; mean age 66 +/- 8 years; range: 50 to 89 years) with aortic valve area 199 mmHg, the mass:volume ratio was increased in men compared with women; of note, the mass:volume ratio in women was not increased in this subgroup compared with the general population. LV pump function in this subgroup was normal and did not differ between men and women. Although no clear-cut difference in hemodynamic parameters was seen, there was a trend towards a less compensatory increase in LV mass in females.

Effect of milrinone on short term outcome of patients with myocardial dysfunction undergoing off-pump coronary artery bypass graft: a randomized clinical trial.

Science.gov (United States)

Hadadzadeh, Mehdi; Hosseini, Seyed Habib; Mostafavi Pour Manshadi, Seyed Mohammad Yousof; Naderi, Nafiseh; Emami Meybodi, Mahmood

2013-01-01

Myocardial dysfunction is a major complication in cardiac surgery that needs inotropic support. This study evaluates the effect of milrinone on patients with low ventricular ejection fraction undergoing off- pump coronary artery bypass graft (OPCAB). The present study is designed to evaluate the effect of milrinone on myocardial dysfunction. Eighty patients with low ventricular ejection fraction (milrinone (50 μg/kg) intravenously and another group received a saline as placebo followed by 24 hours infusion of each agent (0.5 μg/kg/min). Short outcome of patients such as hemodynamic parameters and left ventricular ejection fraction were variables evaluated. Serum levels of creatine phosphokinase, the MB isoenzyme of creatine kinase, occurrence of arrhythmias and mean duration of mechanical ventilation were significantly lower in milrinone group (P<0.05). The mean post operative left ventricular ejection fraction was significantly higher in milrinone group (P=0.031). There were no statistical significant differences between the two groups in terms of intra-aortic balloon pump, inotropic support requirement, myocardial ischemia, myocardial infarction, duration of inotropic support, duration of intensive care unit stay, mortality and morbidity rate. Administration of milrinone in patients undergoing OPCAB with low ventricular ejection fraction is useful and effective.

Anesthetic management of cesarean section in cases of placenta accreta, with versus without abdominal aortic balloon occlusion: study protocol for a randomized controlled trial.

Science.gov (United States)

Chu, Qinjun; Shen, Dan; He, Long; Wang, Hongwei; Zhao, Xianlan; Chen, Zhimin; Wang, Yanli; Zhang, Wei

2017-05-26

Placenta accreta (PA), a severe complication during delivery, is closely linked with massive hemorrhage which could endanger the lives of both mother and baby. Moreover, the incidence of PA has increased dramatically with the increasing rate of cesarean deliveries in the past few decades. Therefore, studies evaluating the effects of different perioperative managements based on different modalities in the treatment of PA are necessary. Among the numerous treatment measures, prophylactic abdominal aortic balloon occlusion (AABO) in combination with cesarean section for PA seems to be more advantageous than others. However, up to now, all studies on AABO were almost retrospective. Current evidence is insufficient to recommend for or against routinely using the AABO technology for control intraoperative hemorrhage in patients with PA. Thus, we hope to carry out a prospective, randomized controlled trial (RCT) study to confirm the effectiveness of the AABO technology in patients with PA. This trial is an investigator-initiated, prospective RCT that will test the superiority of AABO in combination with cesarean section compared to the traditional hysterectomy following cesarean section for parturients with PA. A total of 170 parturients with PA undergoing cesarean section will be randomized to receive either AABO in combination with cesarean section or the traditional hysterectomy following cesarean section. The primary outcome is estimated blood loss. The most important secondary outcome is the occurrence of cesarean hysterectomy during delivery; others include blood transfusion volume, operating time, neonate's Apgar scores (collected at 1, 5 and 10 min), length of stay in intensive care unit, total hospital stay, and balloon occlusion-relative data. This prospective trial will test the superiority of AABO in combination with cesarean section compared to the traditional hysterectomy following cesarean section for parturients with PA. It may provide strong evidence

Percutaneous balloon valvuloplasty in mitral stenosis

International Nuclear Information System (INIS)

Park, Jae Hyung; Oh, Byung Hee; Park, Kyung Ju; Kim, Seung Hyup; Lee, Young Woo; Han, Man Chung

1989-01-01

Percutaneous balloon valvuloplasty(PBV) was successfully performed in 8 mitral stenosis patients for recent 3 months. Five patients have aortic insufficiencies also and two patients have mitral regurgitations below grade II/IV. All patients showed sinus rhythm on EKG, and had no mitral valvular calcification on echocardiography and fluoroscopy. PBV resulted in an increase in mitral valve area from 1.22±0.22 to 2.57±0.86 cm 2 , a decrease in mean left atrial pressure from 23.4±9.6 to 7.5±3.4 mmHg and a decrease in mean mitral pressure gradient from 21.3±9.4 to 6.8±3.1 mmHg. There were no significant complications except 2 cases of newly appeared and mildly aggravated mitral regurgitation. We believe that PBV will become a treatment modality of choice replacing surgical commissurotomy or valve replacement in a group of mitral stenosis patients, because of its effectiveness and safety

Cost-Effectiveness of Transcatheter Aortic Valve Replacement With a Self-Expanding Prosthesis Versus Surgical Aortic Valve Replacement.

Science.gov (United States)

Reynolds, Matthew R; Lei, Yang; Wang, Kaijun; Chinnakondepalli, Khaja; Vilain, Katherine A; Magnuson, Elizabeth A; Galper, Benjamin Z; Meduri, Christopher U; Arnold, Suzanne V; Baron, Suzanne J; Reardon, Michael J; Adams, David H; Popma, Jeffrey J; Cohen, David J

2016-01-05

Previous studies of the cost-effectiveness of transcatheter aortic valve replacement (TAVR) have been based primarily on a single balloon-expandable system. The goal of this study was to evaluate the cost-effectiveness of TAVR with a self-expanding prosthesis compared with surgical aortic valve replacement (SAVR) for patients with severe aortic stenosis and high surgical risk. We performed a formal economic analysis on the basis of individual, patient-level data from the CoreValve U.S. High Risk Pivotal Trial. Empirical data regarding survival and quality of life over 2 years, and medical resource use and hospital costs through 12 months were used to project life expectancy, quality-adjusted life expectancy, and lifetime medical costs in order to estimate the incremental cost-effectiveness of TAVR versus SAVR from a U.S. Relative to SAVR, TAVR reduced initial length of stay an average of 4.4 days, decreased the need for rehabilitation services at discharge, and resulted in superior 1-month quality of life. Index admission and projected lifetime costs were higher with TAVR than with SAVR (differences $11,260 and $17,849 per patient, respectively), whereas TAVR was projected to provide a lifetime gain of 0.32 quality-adjusted life-years ([QALY]; 0.41 LY) with 3% discounting. Lifetime incremental cost-effectiveness ratios were $55,090 per QALY gained and $43,114 per LY gained. Sensitivity analyses indicated that a reduction in the initial cost of TAVR by ∼$1,650 would lead to an incremental cost-effectiveness ratio <$50,000/QALY gained. In a high-risk clinical trial population, TAVR with a self-expanding prosthesis provided meaningful clinical benefits compared with SAVR, with incremental costs considered acceptable by current U.S. With expected modest reductions in the cost of index TAVR admissions, the value of TAVR compared with SAVR in this patient population would become high. (Safety and Efficacy Study of the Medtronic CoreValve System in the Treatment of

Resuscitative Endovascular Balloon Occlusion of the Aorta and Resuscitative Thoracotomy in Select Patients with Hemorrhagic Shock: Early Results from the American Association for the Surgery of Trauma's Aortic Occlusion in Resuscitation for Trauma and Acute Care Surgery Registry.

Science.gov (United States)

Brenner, Megan; Inaba, Kenji; Aiolfi, Alberto; DuBose, Joseph; Fabian, Timothy; Bee, Tiffany; Holcomb, John B; Moore, Laura; Skarupa, David; Scalea, Thomas M

2018-05-01

Aortic occlusion is a potentially valuable tool for early resuscitation in patients nearing extremis or in arrest from severe hemorrhage. The American Association for the Surgery of Trauma's Aortic Occlusion in Resuscitation for Trauma and Acute Care Surgery registry identified trauma patients without penetrating thoracic injury undergoing aortic occlusion at the level of the descending thoracic aorta (resuscitative thoracotomy [RT] or zone 1 resuscitative endovascular balloon occlusion of the aorta [REBOA]) in the emergency department (ED). Survival outcomes relative to the timing of CPR need and admission hemodynamic status were examined. Two hundred and eighty-five patients were included: 81.8% were males, with injury due to penetrating mechanisms in 41.4%; median age was 35.0 years (interquartile range 29 years) and median Injury Severity Score was 34.0 (interquartile range 18). Resuscitative thoracotomy was used in 71%, and zone 1 REBOA in 29%. Overall survival beyond the ED was 50% (RT 44%, REBOA 63%; p = 0.004) and survival to discharge was 5% (RT 2.5%, REBOA 9.6%; p = 0.023). Discharge Glasgow Coma Scale score was 15 in 85% of survivors. Prehospital CPR was required in 60% of patients with a survival beyond the ED of 37% and survival to discharge of 3% (all p > 0.05). Patients who did not require any CPR before had a survival beyond the ED of 70% (RT 48%, REBOA 93%; p American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Energy from solar balloons

Energy Technology Data Exchange (ETDEWEB)

Grena, Roberto [C. R. Casaccia, via Anguillarese 301, 00123 Roma (Italy)

2010-04-15

Solar balloons are hot air balloons in which the air is heated directly by the sun, by means of a black absorber. The lift force of a tethered solar balloon can be used to produce energy by activating a generator during the ascending motion of the balloon. The hot air is then discharged when the balloon reaches a predefined maximum height. A preliminary study is presented, along with an efficiency estimation and some considerations on possible realistic configurations. (author)

Colombian experience with transcatheter aortic valve implantation of medtronic CoreValve.

Science.gov (United States)

Dager, Antonio E; Nuis, Rutger-Jan; Caicedo, Bernardo; Fonseca, Jaime A; Arana, Camilo; Cruz, Lidsa; Benitez, Luis M; Nader, Carlos A; Duenas, Eduardo; de Marchena, Eduardo J; O'Neill, William W; de Jaegere, Peter P

2012-01-01

At our institutions, increasing numbers of aortic stenosis patients were not candidates for surgical aortic valve replacement. Accordingly, we initiated the Cali Colombian Transcatheter Aortic Valve Implantation (TAVI) program. From March 2008 through January 2011, 53 consecutive patients (mean age, 79 ± 6 yr; men, 58%) underwent TAVI with the Medtronic CoreValve System, and data were prospectively collected. Our study's endpoints conformed with Valve Academic Research Consortium recommendations. We report our clinical results.Predicted mortality rates were 25% (interquartile range, 17%-34%) according to logistic EuroSCORE and 6% (interquartile range, 3%-8%) according to the Society of Thoracic Surgeons score. The 30-day mortality rate was 9% (3 intraprocedural deaths, 5 total). The combined 30-day safety endpoint was 30% (major vascular sequelae, 23%; life-threatening bleeding, 12%; myocardial infarction, 4%; major stroke, 4%; and acute kidney injury [stage 3], 2%). Eight patients (15%) required post-implantation balloon dilation and 2 (4%) required valve-in-valve implantation, for a technical device success rate of 77%. Mean peak transvalvular gradient decreased from 74 ± 29 to 17 ± 8 mmHg and mean transvalvular gradient from 40 ± 17 to 8 ± 4 mmHg (both P=0.001). Moderate or severe aortic regurgitation decreased from 32% to 18% (P=0.12) and mitral regurgitation from 32% to 13% (P=0.002). The 1-year survival rate was 81%.We found that TAVI with the CoreValve prosthesis was safe and feasible, with sustained long-term results, for treating aortic stenosis in patients at excessive surgical risk; nonetheless, serious adverse events occurred in 30% of the patients.

Valve thrombosis following transcatheter aortic valve implantation: a systematic review.

Science.gov (United States)

Córdoba-Soriano, Juan G; Puri, Rishi; Amat-Santos, Ignacio; Ribeiro, Henrique B; Abdul-Jawad Altisent, Omar; del Trigo, María; Paradis, Jean-Michel; Dumont, Eric; Urena, Marina; Rodés-Cabau, Josep

2015-03-01

Despite the rapid global uptake of transcatheter aortic valve implantation, valve trombosis has yet to be systematically evaluated in this field. The aim of this study was to determine the clinical characteristics, diagnostic criteria, and treatment outcomes of patients diagnosed with valve thrombosis following transcatheter aortic valve implantation through a systematic review of published data. Literature published between 2002 and 2012 on valve thrombosis as a complication of transcatheter aortic valve implantation was identified through a systematic electronic search. A total of 11 publications were identified, describing 16 patients (mean age, 80 [5] years, 65% men). All but 1 patient (94%) received a balloon-expandable valve. All patients received dual antiplatelet therapy immediately following the procedure and continued to take either mono- or dual antiplatelet therapy at the time of valve thrombosis diagnosis. Valve thrombosis was diagnosed at a median of 6 months post-procedure, with progressive dyspnea being the most common symptom. A significant increase in transvalvular gradient (from 10 [4] to 40 [12] mmHg) was the most common echocardiographic feature, in addition to leaflet thickening. Thrombus was not directly visualized with echocardiography. Three patients underwent valve explantation, and the remaining received warfarin, which effectively restored the mean transvalvular gradient to baseline within 2 months. Systemic embolism was not a feature of valve thrombosis post-transcatheter aortic valve implantation. Although a rare, yet likely under-reported complication of post-transcatheter aortic valve implantation, progressive dyspnea coupled with an increasing transvalvular gradient on echocardiography within the months following the intervention likely signifies valve thrombosis. While direct thrombus visualization appears difficult, prompt initiation of oral anticoagulation therapy effectively restores baseline valve function. Copyright © 2014

Stunning and Right Ventricular Dysfunction Is Induced by Coronary Balloon Occlusion and Rapid Pacing in Humans: Insights From Right Ventricular Conductance Catheter Studies.

Science.gov (United States)

Axell, Richard G; Giblett, Joel P; White, Paul A; Klein, Andrew; Hampton-Til, James; O'Sullivan, Michael; Braganza, Denise; Davies, William R; West, Nick E J; Densem, Cameron G; Hoole, Stephen P

2017-06-06

We sought to determine whether right ventricular stunning could be detected after supply (during coronary balloon occlusion [BO]) and supply/demand ischemia (induced by rapid pacing [RP] during transcatheter aortic valve replacement) in humans. Ten subjects with single-vessel right coronary artery disease undergoing percutaneous coronary intervention with normal ventricular function were studied in the BO group. Ten subjects undergoing transfemoral transcatheter aortic valve replacement were studied in the RP group. In both, a conductance catheter was placed into the right ventricle, and pressure volume loops were recorded at baseline and for intervals over 15 minutes after a low-pressure BO for 1 minute or a cumulative duration of RP for up to 1 minute. Ischemia-induced diastolic dysfunction was seen 1 minute after RP (end-diastolic pressure [mm Hg]: 8.1±4.2 versus 12.1±4.1, P right coronary artery balloon occlusion both cause ischemic right ventricular dysfunction with stunning observed later during the procedure. This may have intraoperative implications in patients without right ventricular functional reserve. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Bioprosthetic Valve Fracture Improves the Hemodynamic Results of Valve-in-Valve Transcatheter Aortic Valve Replacement.

Science.gov (United States)

Chhatriwalla, Adnan K; Allen, Keith B; Saxon, John T; Cohen, David J; Aggarwal, Sanjeev; Hart, Anthony J; Baron, Suzanne J; Dvir, Danny; Borkon, A Michael

2017-07-01

Valve-in-valve (VIV) transcatheter aortic valve replacement (TAVR) may be less effective in small surgical valves because of patient/prosthesis mismatch. Bioprosthetic valve fracture (BVF) using a high-pressure balloon can be performed to facilitate VIV TAVR. We report data from 20 consecutive clinical cases in which BVF was successfully performed before or after VIV TAVR by inflation of a high-pressure balloon positioned across the valve ring during rapid ventricular pacing. Hemodynamic measurements and calculation of the valve effective orifice area were performed at baseline, immediately after VIV TAVR, and after BVF. BVF was successfully performed in 20 patients undergoing VIV TAVR with balloon-expandable (n=8) or self-expanding (n=12) transcatheter valves in Mitroflow, Carpentier-Edwards Perimount, Magna and Magna Ease, Biocor Epic and Biocor Epic Supra, and Mosaic surgical valves. Successful fracture was noted fluoroscopically when the waist of the balloon released and by a sudden drop in inflation pressure, often accompanied by an audible snap. BVF resulted in a reduction in the mean transvalvular gradient (from 20.5±7.4 to 6.7±3.7 mm Hg, P valve effective orifice area (from 1.0±0.4 to 1.8±0.6 cm 2 , P valves to facilitate VIV TAVR with either balloon-expandable or self-expanding transcatheter valves and results in reduced residual transvalvular gradients and increased valve effective orifice area. © 2017 American Heart Association, Inc.

Acute Aortic Arch Perforation During Transcatheter Aortic Valve Replacement in Bicuspid Aortic Stenosis and a Gothic Aortic Arch.

Science.gov (United States)

Millan-Iturbe, Oscar; Sawaya, Fadi J; Bieliauskas, Gintautas; Chow, Danny H F; De Backer, Ole; Søndergaard, Lars

2017-09-01

Transcatheter aortic valve replacement (TAVR) has evolved from a novel technology to an established therapy for high/intermediate-risk patients with severe symptomatic aortic stenosis (AS). Although TAVR is used to treat bicuspid severe AS, the large randomized trials typically excluded bicuspid AS because of its unique anatomic features. This case report describes an acute aortic perforation during delivery of a transcatheter heart valve to treat a severe bicuspid AS with a "gothic aortic arch"; more careful evaluation of the preprocedural multislice computed tomographic scan would have unveiled a sharply angulated aortic arch. This life-threatening complication was successfully treated by thoracic endovascular aortic repair. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Resuscitative endovascular balloon occlusion of the aorta: promise, practice, and progress?

Science.gov (United States)

Perkins, Zane B; Lendrum, Robbie A; Brohi, Karim

2016-12-01

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a minimally invasive damage control procedure for life-threatening abdominal or pelvic haemorrhage. The purpose of this review is to summarize the current understanding and experience with REBOA, outline potential future applications of this technology, and highlight priority areas for further research. REBOA is a feasible method of achieving temporary aortic occlusion and can be performed rapidly, with a high degree of success, in the emergency setting (including at the scene of injury) by appropriately trained clinicians. The procedure supports central perfusion, controls noncompressible haemorrhage, and may improve survival in certain profoundly shocked patient groups; but is also associated with significant risks, including ischaemic tissue damage and procedural complications. Evolutions of this strategy are being explored, with promising proof-of-concept studies in the fields of partial aortic occlusion and the combination of REBOA with extracorporeal support. Noncompressible torso haemorrhage is the leading cause of preventable trauma deaths. The majority of these deaths occur soon after injury, often before any opportunity for definitive haemorrhage control. For a meaningful reduction in trauma mortality, novel methods of rapid haemorrhage control are required.

The role of elastomeric pumps in postoperative analgesia in orthopaedics and factors affecting their flow rate.

Science.gov (United States)

Theodorides, Anthony Andreas

2017-12-01

Elastomeric pumps are mechanical devices composed of an elastomeric balloon reservoir into which the drug to be infused is stored, a protective casing (used by some manufacturers), a flow controller and a wound catheter. In orthopaedics they are used to provide continuous local infiltration analgesia. In this way patients rely less on other routes of analgesia and thus avoid their systemic side effects. Studies have shown good response to analgesia with these pumps for the first 24 hours but their benefit is not as clear at 48 and 72 hours. There are numerous factors that affect the flow rate of elastomeric pumps. Some are inherent to all elastomeric pumps such as: the pressure exerted by the elastomeric balloon, catheter size, the vertical height of the pump in relation to the wound, viscosity and partial filling. There are also other factors which vary according to the manufacturer such as: the optimal temperature to obtain the desired flow rate as this directly affects viscosity, the dialysate that the analgesic drug is mixed with (ie normal saline or 5% dextrose), and the storage conditions of the fluid to be infused. It is thus essential to follow the clinical guidelines provided by the manufacturer in order to obtain the desired flow rate. Copyright the Association for Perioperative Practice.

Clefting in pumpkin balloons

Science.gov (United States)

Baginski, F.; Schur, W.

NASA's effort to develop a large payload, high altitude, long duration balloon, the Ultra Long Duration Balloon, focuses on a pumpkin shape super-pressure design. It has been observed that a pumpkin balloon may be unable to pressurize into the desired cyclically symmetric equilibrium configuration, settling into a distorted, undesired stable state instead. Hoop stress considerations in the pumpkin design leads to choosing the lowest possible bulge radius, while robust deployment is favored by a large bulge radius. Some qualitative understanding of design aspects on undesired equilibria in pumpkin balloons has been obtained via small-scale balloon testing. Poorly deploying balloons have clefts, but most gores away from the cleft deploy uniformly. In this paper, we present models for pumpkin balloons with clefts. Long term success of the pumpkin balloon for NASA requires a thorough understanding of the phenomenon of multiple stable equilibria and means for quantitative assessment of measures that prevent their occurrence. This paper attempts to determine numerical thresholds of design parameters that distinguish between properly deploying designs and improperly deploying designs by analytically investigating designs in the vicinity of criticality. Design elements which may trigger the onset undesired equilibria and remedial measures that ensure deployment are discussed.

Understanding the C-pulse device and its potential to treat heart failure.

Science.gov (United States)

Sales, Virna L; McCarthy, Patrick M

2010-03-01

The Sunshine Heart C-Pulse (C-Pulse; Sunshine Heart Inc., Tustin, CA) device is an extra-aortic implantable counterpulsation pump designed as a non-blood contacting ambulatory heart assist device, which may provide relief from symptoms for class II-III congestive heart failure patients. It has a comparable hemodynamic augmentation to intra-aortic balloon counterpulsation devices. The C-Pulse cuff is implanted through a median sternotomy, secured around the ascending aorta, and pneumatically driven by an external system controller. Pre-clinical studies in the acute pig model, and initial temporary clinical studies in patients undergoing off-pump coronary bypass surgery have shown substantial increase in diastolic perfusion of the coronary vessels, which translated to a favorable improvement in ventricular function. A U.S. prospective multi-center trial to evaluate the safety and efficacy of the C-Pulse in class III patients with moderate heart failure is now in progress.

Balloon sinuplasty

OpenAIRE

Ahmad, Zahoor

2010-01-01

Balloon sinuplasty is a technique in endoscopic sinus surgery that involves minimally invasive procedures to dilate the obstructed or stenosed anatomical sinus pathways. Procedure is derived from the well-recognized techinique of angioplasty. This article highlights the procedural methods with review of literature and my personal experience in balloon sinupalsty.

Effect of milrinone on short term outcome of patients with myocardial dysfunction undergoing off-pump coronary artery bypass graft: a randomized clinical trial.

Directory of Open Access Journals (Sweden)

Mehdi Hadadzadeh

2013-10-01

Full Text Available Myocardial dysfunction is a major complication in cardiac surgery that needs inotropic support. This study evaluates the effect of milrinone on patients with low ventricular ejection fraction undergoing off- pump coronary artery bypass graft (OPCAB. The present study is designed to evaluate the effect of milrinone on myocardial dysfunction. Eighty patients with low ventricular ejection fraction (<35%, candidate for elective OPCAB, were enrolled in this study. They were randomly assigned to two groups. One group received milrinone (50 μg/kg intravenously and another group received a saline as placebo followed by 24 hours infusion of each agent (0.5 μg/kg/min. Short outcome of patients such as hemodynamic parameters and left ventricular ejection fraction were variables evaluated. Serum levels of creatine phosphokinase, the MB isoenzyme of creatine kinase, occurrence of arrhythmias and mean duration of mechanical ventilation were significantly lower in milrinone group (P<0.05. The mean post operative left ventricular ejection fraction was significantly higher in milrinone group (P=0.031. There were no statistical significant differences between the two groups in terms of intra-aortic balloon pump, inotropic support requirement, myocardial ischemia, myocardial infarction, duration of inotropic support, duration of intensive care unit stay, mortality and morbidity rate. Administration of milrinone in patients undergoing OPCAB with low ventricular ejection fraction is useful and effective.

Balloon Occlusion of the Contralateral Iliac Artery to Assist Recanalization of the Ipsilateral Iliac Artery in Total Aortoiliac Occlusion: A Technical Note

Directory of Open Access Journals (Sweden)

Abdel Aziz A. Jaffan

2013-01-01

Full Text Available Endovascular recanalization of chronic total aortoiliac occlusion is technically challenging. Inability to reenter the true aortic lumen, following retrograde iliac recanalization, is one of the most common causes of failure. We describe a case of a total aortoiliac occlusion where balloon occlusion of the right common iliac artery, following its recanalization from a brachial approach, was used to facilitate antegrade recanalization of the occluded contralateral left common iliac artery.

Under Pressure: Activities with a Vacuum Pump (and Some Marshmallows) Help Students Learn about Pressure.

Science.gov (United States)

Galus, Pamela

2002-01-01

Introduces a science demonstration that illustrates the effects of pressure and gravity on humans using a marshmallow man and a vacuum pump. Demonstrates the same concept with shaving cream, balloons, and boiling water without raising temperature. (YDS)

Aortic insufficiency

Science.gov (United States)

... page, please enable JavaScript. Aortic insufficiency is a heart valve disease in which the aortic valve does not close ... aortic insufficiency Images Aortic insufficiency References Carabello BA. Valvular heart disease. In: Goldman L, Schafer AI, eds. Goldman-Cecil ...

Status of the NASA Balloon Program

Science.gov (United States)

Needleman, H. C.; Nock, R. S.; Bawcom, D. W.

1993-02-01

In the early 1980's the U.S. National Aeronautics and Space Administration (NASA) Balloon Program was faced with a problem of catastrophic balloon failures. In 1986 a balloon recovery program was initiated. This program included qualification of new balloon films, and investigations into materials, processing, structures and performance of balloons. This recovery program has been very successful. To date, more than 100 balloons manufactured of newly developed films have been flown with unprecedented success. There has been much progress made across the spectrum of balloon related disciplines. A new design philosophy has been developed and is being used for all NASA balloons. An updated balloon reliability and quality assurance program is in effect. The long duration balloon development project has been initiated with the first flight test having been conducted in December 1989 from Antarctica. A comprehensive research and development (R&D) effort has been initiated and is progressing well. The progress, status and future plans for these and other aspects of the NASA program, along with a description of the comprehensive balloon R&D activity, will be presented.

Investigation of hot air balloon fatalities.

Science.gov (United States)

McConnell, T S; Smialek, J E; Capron, R G

1985-04-01

The rising popularity of the sport of hot air ballooning has been accompanied by several recent incidents, both in this country and other parts of the world, where mechanical defects and the improper operation of balloons have resulted in several fatalities. A study was conducted to identify the location and frequency of hot air ballooning accidents. Furthermore, the study attempted to identify those accidents that were the result of improper handling on the part of the balloon operators and those that were related to specific defects in the construction of the balloon. This paper presents a background of the sport of hot air ballooning, together with an analysis of the construction of a typical hot air balloon, pointing out the specific areas where defects may occur that could result in a potential fatal balloon crash. Specific attention is given to the two recent balloon crashes that occurred in Albuquerque, N.M., hot air balloon capital of the world, and that resulted in multiple fatalities.

Early results of valve-sparing ascending aortic replacement in type A aortic dissection and aortic insufficiency

Directory of Open Access Journals (Sweden)

М. Л. Гордеев

2016-08-01

Full Text Available Aim: The study was designed to investigate predictors of effective valve-sparing ascending aortic replacement in patients with Stanford type A aortic dissection combined with aortic insufficiency and to analyze efficacy and safety of this kind of surgery.Methods: From January 2010 to December 2015, 49 patients with Stanford type A aortic dissection combined with aortic insufficiency underwent ascending aortic replacement. All patients were divided into 3 groups: valve-sparing procedures (group 1, n = 11, combined aortic valve and supracoronary ascending aortic replacement (group 2, n = 12, and Bentall procedure (group 3, n = 26. We assessed the initial status of patients, incidence of complications and efficacy of valve-sparing ascending aortic replacement.Results: The hospital mortality rate was 8.2% (4/49 patients. The amount of surgical correction correlated with the initial diameter of the aorta at the level of the sinuses of Valsalva. During the hospital period, none of patients from group 1 developed aortic insufficiency exceeding Grade 2 and the vast majority of patients had trivial aortic regurgitation. The parameters of cardiopulmonary bypass, cross-clamp time and circulatory arrest time did not correlate with the initial size of the ascending aorta and aortic valve blood flow impairment, neither did they influence significantly the incidence and severity of neurological complications. The baseline size of the ascending aorta and degree of aortic regurgitation did not impact the course of the early hospital period.Conclusions: Supracoronary ascending aortic replacement combined with aortic valve repair in ascending aortic dissection and aortic regurgitation is effective and safe. The initial size of the ascending aorta and aortic arch do not influence immediate results. The diameter of the aorta at the level of the sinuses of Valsalva and the condition of aortic valve leaflets could be considered as the limiting factors. Further long

Cleft formation in pumpkin balloons

Science.gov (United States)

Baginski, Frank E.; Brakke, Kenneth A.; Schur, Willi W.

NASA’s development of a large payload, high altitude, long duration balloon, the Ultra Long Duration Balloon, centers on a pumpkin shape super-pressure design. Under certain circumstances, it has been observed that a pumpkin balloon may be unable to pressurize into the desired cyclically symmetric equilibrium configuration, settling into a distorted, undesired state instead. Success of the pumpkin balloon for NASA requires a thorough understanding of the phenomenon of multiple stable equilibria and developing of means for the quantitative assessment of design measures that prevent the occurrence of undesired equilibrium. In this paper, we will use the concept of stability to classify cyclically symmetric equilibrium states at full inflation and pressurization. Our mathematical model for a strained equilibrium balloon, when applied to a shape that mimics the Phase IV-A balloon of Flight 517, predicts instability at float. Launched in Spring 2003, this pumpkin balloon failed to deploy properly. Observations on pumpkin shape type super-pressure balloons that date back to the 1980s suggest that within a narrowly defined design class of pumpkin shape super-pressure balloons where individual designs are fully described by the number of gores ng and by a single measure of the bulging gore shape, the designs tend to become more vulnerable with the growing number of gores and with the diminishing size of the bulge radius rB Weight efficiency considerations favor a small bulge radius, while robust deployment into the desired cyclically symmetrical configuration becomes more likely with an increased bulge radius. In an effort to quantify this dependency, we will explore the stability of a family of balloon shapes parametrized by (ng, rB) which includes a design that is very similar, but not identical, to the balloon of Flight 517. In addition, we carry out a number of simulations that demonstrate other aspects related to multiple equilibria of pumpkin balloons.

Aspirin Versus Aspirin Plus Clopidogrel as Antithrombotic Treatment Following Transcatheter Aortic Valve Replacement With a Balloon-Expandable Valve: The ARTE (Aspirin Versus Aspirin + Clopidogrel Following Transcatheter Aortic Valve Implantation) Randomized Clinical Trial.

Science.gov (United States)

Rodés-Cabau, Josep; Masson, Jean-Bernard; Welsh, Robert C; Garcia Del Blanco, Bruno; Pelletier, Marc; Webb, John G; Al-Qoofi, Faisal; Généreux, Philippe; Maluenda, Gabriel; Thoenes, Martin; Paradis, Jean-Michel; Chamandi, Chekrallah; Serra, Vicenç; Dumont, Eric; Côté, Mélanie

2017-07-10

The aim of this study was to compare aspirin plus clopidogrel with aspirin alone as antithrombotic treatment following transcatheter aortic valve replacement (TAVR) for the prevention of ischemic events, bleeding events, and death. Few data exist on the optimal antithrombotic therapy following TAVR. This was a randomized controlled trial comparing aspirin (80 to 100 mg/day) plus clopidogrel (75 mg/day) (dual antiplatelet therapy [DAPT]) versus aspirin alone (single-antiplatelet therapy [SAPT]) in patients undergoing TAVR with a balloon-expandable valve. The primary endpoint was the occurrence of death, myocardial infarction (MI), stroke or transient ischemic attack, or major or life-threatening bleeding (according to Valve Academic Research Consortium 2 definitions) within the 3 months following the procedure. The trial was prematurely stopped after the inclusion of 74% of the planned study population. A total of 222 patients were included, 111 allocated to DAPT and 111 to SAPT. The composite of death, MI, stroke or transient ischemic attack, or major or life-threatening bleeding tended to occur more frequently in the DAPT group (15.3% vs. 7.2%, p = 0.065). There were no differences between groups in the occurrence of death (DAPT, 6.3%; SAPT, 3.6%; p = 0.37), MI (DAPT, 3.6%; SAT, 0.9%; p = 0.18), or stroke or transient ischemic attack (DAPT, 2.7%; SAPT, 0.9%; p = 0.31) at 3 months. DAPT was associated with a higher rate of major or life-threatening bleeding events (10.8% vs. 3.6% in the SAPT group, p = 0.038). There were no differences between groups in valve hemodynamic status post-TAVR. This small trial showed that SAPT (vs. DAPT) tended to reduce the occurrence of major adverse events following TAVR. SAPT reduced the risk for major or life-threatening events while not increasing the risk for MI or stroke. Larger studies are needed to confirm these results. (Aspirin Versus Aspirin + Clopidogrel Following Transcatheter Aortic Valve Implantation: The ARTE

Weather Balloon Ascent Rate

Science.gov (United States)

Denny, Mark

2016-05-01

The physics of a weather balloon is analyzed. The surprising aspect of the motion of these balloons is that they ascend to great altitudes (typically 35 km) at a more or less constant rate. Such behavior is not surprising near the ground—say for a helium-filled party balloon rising from street level to the top of the Empire State building—but it is unexpected for a balloon that rises to altitudes where the air is rarefied. We show from elementary physical laws why the ascent rate is approximately constant.

Reinforced aortic root reconstruction for acute type A aortic dissection involving the aortic root

Directory of Open Access Journals (Sweden)

Han Qing-qi

2013-06-01

Full Text Available OBJECTIVE: There are debates regarding the optimal approach for AAAD involving the aortic root. We described a modified reinforced aortic root reconstruction approach for treating AAAD involving the aortic root. METHODS: A total of 161 patients with AAAD involving the aortic root were treated by our modified reinforced aortic root reconstruction approach from January 1998 to December 2008. Key features of our modified approach were placement of an autologous pericardial patch in the false lumen, lining of the sinotubular junction lumen with a polyester vascular ring, and wrapping of the vessel with Teflon strips. Outcome measures included post-operative mortality, survival, complications, and level of aortic regurgitation. RESULTS: A total of 161 patients were included in the study (mean age: 43.3 1 15.5 years. The mean duration of follow-up was 5.1 1 2.96 years (2-12 years. A total of 10 (6.2% and 11 (6.8% patients died during hospitalization and during follow-up, respectively. Thirty-one (19.3% patients experienced postoperative complications. The 1-, 3-, 5-, and 10-year survival rates were 99.3%, 98%, 93.8%, and 75.5%, respectively. There were no instances of recurrent aortic dissection, aortic aneurysm, or pseudoaneurysm during the entire study period. The severity of aortic regurgitation dramatically decreased immediately after surgery (from 28.6% to 0% grade 3-4 and thereafter slightly increased (from 0% to 7.2% at 5 years and 9.1% at 10 years. CONCLUSION: This modified reinforced aortic root reconstruction was feasible, safe and durable/effective, as indicated by its low mortality, low postoperative complications and high survival rate.

[Right patent ductus arteriosus with an ipsilateral aortic arch: percutaneous closure with amplatzer devices].

Science.gov (United States)

Santiago, Justo; Acuña, Manuel; Arispe, Elizabeth; Camargo, Ronaldo; Neves, Juliana; Arnoni, Daniel; Fontes, Valmir F; Pedra, Carlos A

2007-03-01

The association of a right aortic arch with an ipsilateral patent ductus arteriosus is rare, especially when there are no other intracardiac anomalies. We report three female patients aged 26, 35 and 9 years with this combination in whom previous attempts at surgical closure by thoracotomy and sternotomy were unsuccessful and who subsequently underwent successful percutaneous closure of the defects using Amplatzer devices. In two patients, although angiography demonstrated the presence of type-A patent ductus arteriosus, it was not possible to determine the minimum diameter accurately and it was necessary to measure it using a sizing balloon. An Amplatzer duct occluder was used in two patients and an Amplatzer muscular ventricular septal defect occluder, in the other. In all patients, full closure was confirmed in the catheterization laboratory and the patients were discharged on the same day with no complications. Percutaneous closure of a right patent ductus arteriosus associated with a right aortic arch is feasible, safe and effective.

Development of a New Intravascular Low-Profile Device for Exclusion of Aortic Aneurysm: An Experimental Pilot Study

International Nuclear Information System (INIS)

Strecker, Ernst-Peter; Haberstroh, Joerg; Boos, Irene; Metz, Stephan; Langer, Mathias; Moliner, Manuel Maynar

2004-01-01

Purpose: To present a new intravascular device for the treatment of aorto-iliac aneurysms. Methods: This new device was tested in five dogs with abdominal aortic aneurysm created experimentally by overdilation of a balloon-expandable stent with a 16 or 18 mm wide PTA balloon catheter. The design of the device is based on a self-expanding aortic stent which consists of two stretchable circular frames filled with a textile Dacron mesh membrane that is suspended horizontally into the infrarenal abdominal aorta proximally to the aneurysm. The frames are part of a preshaped double helical structure that is introduced longitudinally through a catheter in a parallel fashion and forming the desired shape at the vessel site to be occluded. Two iliac stent-grafts are introduced in a low-profile status through the membrane sealing the aneurysm sac and holding the stent-grafts in place. After stent-graft expansion, a new bifurcation located more proximally than the natural one is created. The follow-up of the dogs was performed clinically and angiographically, and specimens were evaluated histomorphologically. Results: The membrane device can be introduced through a 9 Fr vascular sheath. Technical success was achieved in four of five dogs. Nine of ten stent-grafts could be fixed securely within the membrane, thus preventing dislocation. Aneurysms were excluded immediately, and blood flow to the external iliac arteries was restored by the stent-grafts. At 6-9 months follow-up of technically successful implanted devices, there were no endoleaks, no migration, no stenoses at contact sites between the implant material and vascular wall, and no stenosis or occlusion of the stent-grafts. At microscopic evaluation, the interspace between the membranes was filled with thrombotic material, thus ensuring exclusion of the aneurysm. Conclusion: This new device was found to be flexible, low profile and useful in excluding abdominal aortic aneurysm in the experimental setting

Effects of atmospheric pressure conditions on flow rate of an elastomeric infusion pump.

Science.gov (United States)

Wang, Jong; Moeller, Anna; Ding, Yuanpang Samuel

2012-04-01

The effects of pressure conditions, both hyperbaric and hypobaric, on the flow rate of an elastomeric infusion pump were investigated. The altered pressure conditions were tested with the restrictor outlet at two different conditions: (1) at the same pressure condition as the Infusor elastomeric balloon and (2) with the outlet exposed to ambient conditions. Five different pressure conditions were tested. These included ambient pressure (98-101 kilopascals [kPa]) and test pressures controlled to be 10 or 20 kPa below or 75 or 150 kPa above the ambient pressure. A theoretical calculation based on the principles of fluid mechanics was also used to predict the pump's flow rate at various ambient conditions. The conditions in which the Infusor elastomeric pump and restrictor outlet were at the same pressure gave rise to average flow rates within the ±10% tolerance of the calculated target flow rate of 11 mL/hr. The flow rate of the Infusor pump decreased when the pressure conditions changed from hypobaric to ambient. The flow rate increased when the pressure conditions changed from hyperbaric to ambient. The flow rate of the Infusor elastomeric pump was not affected when the balloon reservoir and restrictor outlet were at the same pressure. The flow rate varied from 58.54% to 377.04% of the labeled flow rate when the pressure applied to the reservoir varied from 20 kPa below to 150 kPa above the pressure applied to the restrictor outlet, respectively. The maximum difference between observed flow rates and those calculated by applying fluid mechanics was 4.9%.

MMP-2 Isoforms in Aortic Tissue and Serum of Patients with Ascending Aortic Aneurysms and Aortic Root Aneurysms

Science.gov (United States)

Tscheuschler, Anke; Meffert, Philipp; Beyersdorf, Friedhelm; Heilmann, Claudia; Kocher, Nadja; Uffelmann, Xenia; Discher, Philipp; Siepe, Matthias; Kari, Fabian A.

2016-01-01

Objective The need for biological markers of aortic wall stress and risk of rupture or dissection of ascending aortic aneurysms is obvious. To date, wall stress cannot be related to a certain biological marker. We analyzed aortic tissue and serum for the presence of different MMP-2 isoforms to find a connection between serum and tissue MMP-2 and to evaluate the potential of different MMP-2 isoforms as markers of high wall stress. Methods Serum and aortic tissue from n = 24 patients and serum from n = 19 healthy controls was analyzed by ELISA and gelatin zymography. 24 patients had ascending aortic aneurysms, 10 of them also had aortic root aneurysms. Three patients had normally functioning valves, 12 had regurgitation alone, eight had regurgitation and stenosis and one had only stenosis. Patients had bicuspid and tricuspid aortic valves (9/15). Serum samples were taken preoperatively, and the aortic wall specimen collected during surgical aortic repair. Results Pro-MMP-2 was identified in all serum and tissue samples. Pro-MMP-2 was detected in all tissue and serum samples from patients with ascending aortic/aortic root aneurysms, irrespective of valve morphology or other clinical parameters and in serum from healthy controls. We also identified active MMP-2 in all tissue samples from patients with ascending aortic/aortic root aneurysms. None of the analyzed serum samples revealed signals relatable to active MMP-2. No correlation between aortic tissue total MMP-2 or tissue pro-MMP-2 or tissue active MMP-2 and serum MMP-2 was found and tissue MMP-2/pro-MMP-2/active MMP-2 did not correlate with aortic diameter. This evidence shows that pro-MMP-2 is the predominant MMP-2 species in serum of patients and healthy individuals and in aneurysmatic aortic tissue, irrespective of aortic valve configuration. Active MMP-2 species are either not released into systemic circulation or not detectable in serum. There is no reliable connection between aortic tissue—and serum MMP-2

Scientific Ballooning in India - Recent Developments

Science.gov (United States)

Manchanda, R. K.; Srinivasan, S.; Subbarao, J. V.

Established in 1972, the National Balloon Facility operated by TIFR in Hyderabad, India is is a unique facility in the country, which provides a complete solution in scientific ballooning. It is also one of its kind in the world since it combines both, the in-house balloon production and a complete flight support for scientific ballooning. With a large team working through out the year to design, fabricate and launch scientific balloons, the Hyderabad Facility is a unique centre of expertise where the balloon design, Research and Development, the production and launch facilities are located under one roof. Our balloons are manufactured from 100% indigenous components. The mission specific balloon design, high reliability control and support instrumentation, in-house competence in tracking, telemetry, telecommand, data processing, system design and mechanics is a hallmark of the Hyderabad balloon facility. In the past few years we have executed a major programme of upgradation of different components of balloon production, telemetry and telecommand hardware and various support facilities. This paper focuses on our increased capability of balloon production of large sizes up to size of 780,000 M^3 using Antrix film, development of high strength balloon load tapes with the breaking strength of 182 kg, and the recent introduction of S-band telemetry and a commandable timer cut-off unit in the flight hardware. A summary of the various flights conducted in recent years will be presented along with the plans for new facilities.

Results of aortic root reimplantation in patients with ascending aortic aneurysm and concomitant aortic insufficiency

Directory of Open Access Journals (Sweden)

А. М. Чернявский

2016-01-01

Full Text Available Objective. The research was designed to evaluate the results of valve-sparing operations: aortic root reimplantation versus aortic valve reimplantation when repairing an ascending aortic aneurysm with concomitant aortic insufficiency.Methods. Within a blind prospective randomized study conducted over a period from 2011 to 2015, 64 patients underwent aortic valve-sparing surgery. The inclusion criteria were the presence of an aortic aneurysm of the ascending aorta exceeding 4.5 cm and concomitant aortic insufficiency. All patients were divided into two groups: FS-group, aortic root reimplantation (modified Florida Sleeve technique (n = 32 and D-group, aortic valve reimplantation (David procedure (n = 32. The average age of patients was 57±13 (23–73 years in the FS-group and 55±11 (15–72 years in the D-group (p = 0.54. Both groups had 78% of males (p>0.99. A Marfan syndrome was identified in 6% and 9% in the FS-group and D-group respectively (p>0.99. Mean diameter of the sinuses of Valsalva was 51±7 mm and 56±10 mm (p = 0.09, aortic insufficiency 2.6±0.7 and 2.8±0.8 (p = 0.15 in the FS-group and D-group respectively. In the FS-group and D-group LVEDD amounted to 5.5±0.7 mm and 5.9±1.0 mm (p = 0.09 respectively. All patients took echocardiography in the preoperative, postoperative and follow-up periods.Results. In the long-term period, the degree of aortic regurgitation was 1.2±0.1 in the FS-group and 1.3±0.6 in the D-group (p = 0.72. LVEDD was 123±23 mm in the FS-group and 139.6±80 mm in the D-group at follow-up (p = 0.77. There were no statistically significant differences in the analysis of complications. Overall 30-day in-hospital mortality was 7.8%. There were 2 (6.3% deaths in the FS-group and 3 (9.4% in the D-group (p = 0.5.Late mortality was 6.3% in the FS-group and 3.1% in the D-group (p>0.99. Cumulative survival at 4 years was 84.3% and 84.8% in the FS-group and the D-group respectively (p = 0.94. Cumulative freedom from

Is Decellularized Porcine Small Intestine Sub-mucosa Patch Suitable for Aortic Arch Repair?

Science.gov (United States)

Corno, Antonio F.; Smith, Paul; Bezuska, Laurynas; Mimic, Branko

2018-01-01

Introduction: We reviewed our experience with decellularized porcine small intestine sub-mucosa (DPSIS) patch, recently introduced for congenital heart defects. Materials and Methods: Between 10/2011 and 04/2016 a DPSIS patch was used in 51 patients, median age 1.1 months (5 days to 14.5 years), for aortic arch reconstruction (45/51 = 88.2%) or aortic coarctation repair (6/51 = 11.8%). All medical records were retrospectively reviewed, with primary endpoints interventional procedure (balloon dilatation) or surgery (DPSIS patch replacement) due to patch-related complications. Results: In a median follow-up time of 1.5 ± 1.1 years (0.6–2.3years) in 13/51 patients (25.5%) a re-intervention, percutaneous interventional procedure (5/51 = 9.8%) or re-operation (8/51 = 15.7%) was required because of obstruction in the correspondence of the DPSIS patch used to enlarge the aortic arch/isthmus, with median max velocity flow at Doppler interrogation of 4.0 ± 0.51 m/s. Two patients required surgery after failed interventional cardiology. The mean interval between DPSIS patch implantation and re-intervention (percutaneous procedure or re-operation) was 6 months (1–17 months). While there were 3 hospital deaths (3/51 = 5.9%) not related to the patch implantation, no early or late mortality occurred for the subsequent procedure required for DPSIS patch interventional cardiology or surgery. The median max velocity flow at Doppler interrogation through the aortic arch/isthmus for the patients who did not require interventional procedure or surgery was 1.7 ± 0.57 m/s. Conclusions: High incidence of re-interventions with DPSIS patch for aortic arch and/or coarctation forced us to use alternative materials (homografts and decellularized gluteraldehyde preserved bovine pericardial matrix). PMID:29900163

Decreased expression of fibulin-4 in aortic wall of aortic dissection.

Science.gov (United States)

Huawei, P; Qian, C; Chuan, T; Lei, L; Laing, W; Wenlong, X; Wenzhi, L

2014-02-01

In this research, we will examine the expression of Fibulin-4 in aortic wall to find out its role in aortic dissection development. The samples of aortic wall were obtained from 10 patients operated for acute ascending aortic dissection and five patients for chronic ascending aortic dissection. Another 15 pieces of samples from patients who had coronary artery bypass were as controls. The aortic samples were stained with aldehyde magenta dyeing to evaluate the arrangement of elastic fibers. The Fibulin-4 protein and mRNA expression were both determined by Western blot and realtime quantitative polymerase chain reaction. Compared with the control group, both in acute and chronic ascending aortic dissection, elastic fiber fragments increased and the expression of fibulin-4 protein significantly decreased (P= 0.045 < 0.05). The level of fibulin-4 mRNA decreased in acute ascending aortic dissection (P= 0.034 < 0.05), while it increased in chronic ascending aortic dissection (P=0.004 < 0.05). The increased amounts of elastic fiber fragments were negatively correlated with the expression of fibulin-4 mRNA in acute ascending aortic dissection. In conclusion, in aortic wall of ascending aortic dissection, the expression of fibulin-4 protein decreased and the expression of fibulin-4 mRNA was abnormal. Fibulin-4 may play an important role in the pathogenesis of aortic dissection.

Scientific ballooning in India Recent developments

Science.gov (United States)

Manchanda, R. K.

Established in 1971, the National Balloon Facility operated by TIFR in Hyderabad, India, is a unique facility in the country, which provides a complete solution in scientific ballooning. It is also one of its kind in the world since it combines both, the in-house balloon production and a complete flight support for scientific ballooning. With a large team working through out the year to design, fabricate and launch scientific balloons, the Hyderabad Facility is a unique centre of expertise where the balloon design, research and development, the production and launch facilities are located under one roof. Our balloons are manufactured from 100% indigenous components. The mission specific balloon design, high reliability control and support instrumentation, in-house competence in tracking, telemetry, telecommand, data processing, system design and mechanics is its hallmark. In the past few years, we have executed a major programme of upgradation of different components of balloon production, telemetry and telecommand hardware and various support facilities. This paper focuses on our increased capability of balloon production of large sizes up to 780,000 m 3 using Antrix film, development of high strength balloon load tapes with the breaking strength of 182 kg, and the recent introduction of S-band telemetry and a commandable timer cut-off unit in the flight hardware. A summary of the various flights conducted in recent years will be presented along with the plans for new facilities.

Reoperative Aortic Root Replacement in Patients with Previous Aortic Root or Aortic Valve Procedures

Directory of Open Access Journals (Sweden)

Byung Kwon Chong

2016-08-01

Full Text Available Background: Generalization of standardized surgical techniques to treat aortic valve (AV and aortic root diseases has benefited large numbers of patients. As a consequence of the proliferation of patients receiving aortic root surgeries, surgeons are more frequently challenged by reoperative aortic root procedures. The aim of this study was to evaluate the outcomes of redo-aortic root replacement (ARR. Methods: We retrospectively reviewed 66 patients (36 male; mean age, 44.5±9.5 years who underwent redo-ARR following AV or aortic root procedures between April 1995 and June 2015. Results: Emergency surgeries comprised 43.9% (n=29. Indications for the redo-ARR were aneurysm (n=12, pseudoaneurysm (n=1, or dissection (n=6 of the residual native aortic sinus in 19 patients (28.8%, native AV dysfunction in 8 patients (12.1%, structural dysfunction of an implanted bioprosthetic AV in 19 patients (28.8%, and infection of previously replaced AV or proximal aortic grafts in 30 patients (45.5%. There were 3 early deaths (4.5%. During follow- up (median, 54.65 months; quartile 1–3, 17.93 to 95.71 months, there were 14 late deaths (21.2%, and 9 valve-related complications including reoperation of the aortic root in 1 patient, infective endocarditis in 3 patients, and hemorrhagic events in 5 patients. Overall survival and event-free survival rates at 5 years were 81.5%±5.1% and 76.4%±5.4%, respectively. Conclusion: Despite technical challenges and a high rate of emergency conditions in patients requiring redo-ARR, early and late outcomes were acceptable in these patients.

Assessment of structural valve deterioration of transcatheter aortic bioprosthetic balloon-expandable valves using the new European consensus definition.

Science.gov (United States)

Eltchaninoff, Hélène; Durand, Eric; Avinée, Guillaume; Tron, Christophe; Litzler, Pierre-Yves; Bauer, Fabrice; Dacher, Jean-Nicolas; Werhlin, Camille; Bouhzam, Najime; Bettinger, Nicolas; Candolfi, Pascal; Cribier, Alain

2018-03-30

Durability of transcatheter aortic bioprosthetic valves remains a major issue. Standardised definitions of deterioration and failure of bioprosthetic valves have recently been proposed. The aim of this study was to assess structural transcatheter valve deterioration (SVD) and bioprosthetic valve failure (BVF) using these new definitions. All TAVI patients implanted up to September 2012 with a minimal theoretical five-year follow-up were included. Systematic clinical and echocardiographic follow-up was performed annually. New standardised definitions were used to assess durability of transcatheter aortic bioprosthetic valves. From 2002 to 2012, 378 patients were included. Mean age and logistic EuroSCORE were 83.3±6.8 years and 22.8±13.1%. Thirty-day mortality was 13.2%. Nine patients had SVD including two severe forms and two patients had definite late BVF. The incidence of SVD and BVF at eight years was 3.2% (95% CI: 1.45-6.11) and 0.58% (95% CI: 0.15-2.75), respectively. Even though limited by the poor survival of the very high-risk/compassionate early population, our data do not demonstrate any alarm concerning transcatheter aortic valve durability. Careful prospective assessment in younger and lower-risk patients and comparison with surgical bioprosthetic valves are required for further assessment of the long-term durability of transcatheter valves.

Wall stress on ascending thoracic aortic aneurysms with bicuspid compared with tricuspid aortic valve.

Science.gov (United States)

Xuan, Yue; Wang, Zhongjie; Liu, Raymond; Haraldsson, Henrik; Hope, Michael D; Saloner, David A; Guccione, Julius M; Ge, Liang; Tseng, Elaine

2018-03-08

Guidelines for repair of bicuspid aortic valve-associated ascending thoracic aortic aneurysms have been changing, most recently to the same criteria as tricuspid aortic valve-ascending thoracic aortic aneurysms. Rupture/dissection occurs when wall stress exceeds wall strength. Recent studies suggest similar strength of bicuspid aortic valve versus tricuspid aortic valve-ascending thoracic aortic aneurysms; thus, comparative wall stress may better predict dissection in bicuspid aortic valve versus tricuspid aortic valve-ascending thoracic aortic aneurysms. Our aim was to determine whether bicuspid aortic valve-ascending thoracic aortic aneurysms had higher wall stresses than their tricuspid aortic valve counterparts. Patients with bicuspid aortic valve- and tricuspid aortic valve-ascending thoracic aortic aneurysms (bicuspid aortic valve = 17, tricuspid aortic valve = 19) greater than 4.5 cm underwent electrocardiogram-gated computed tomography angiography. Patient-specific 3-dimensional geometry was reconstructed and loaded to systemic pressure after accounting for prestress geometry. Finite element analyses were performed using the LS-DYNA solver (LSTC Inc, Livermore, Calif) with user-defined fiber-embedded material model to determine ascending thoracic aortic aneurysm wall stress. Bicuspid aortic valve-ascending thoracic aortic aneurysms 99th-percentile longitudinal stresses were 280 kPa versus 242 kPa (P = .028) for tricuspid aortic valve-ascending thoracic aortic aneurysms in systole. These stresses did not correlate to diameter for bicuspid aortic valve-ascending thoracic aortic aneurysms (r = -0.004) but had better correlation to tricuspid aortic valve-ascending thoracic aortic aneurysms diameter (r = 0.677). Longitudinal stresses on sinotubular junction were significantly higher in bicuspid aortic valve-ascending thoracic aortic aneurysms than in tricuspid aortic valve-ascending thoracic aortic aneurysms (405 vs 329 kPa, P = .023). Bicuspid

Six-Month Outcomes After High-Risk Coronary Artery Bypass Graft Surgery and Preoperative Intra-aortic Balloon Counterpulsation Use: An Inception Cohort Study.

Science.gov (United States)

Litton, Edward; Bass, Frances; Delaney, Anthony; Hillis, Graham; Marasco, Silvana; McGuinness, Shay; Myles, Paul S; Reid, Christopher M; Smith, Julian A

2018-01-05

To inform the design of a pivotal randomized controlled trial of prophylactic intra-aortic balloon counterpulsation (IABC) in patients undergoing coronary artery bypass graft (CABG) at high risk of postoperative low cardiac output syndrome (LCOS). Inception cohort study. A total of 13 established cardiac centers in Australia, Canada, New Zealand, and the United Kingdom. Adult patients were eligible for inclusion if they were listed for CABG surgery and had 2 or more LCOS risk factors (low ejection fraction, severe left main coronary artery disease, redo sternotomy, unstable angina). Outcomes of interest were a composite outcome of in-hospital mortality, postoperative acute myocardial infarction (AMI), acute kidney injury (AKI), or stroke as well as 6-month vital status and quality of life using the EuroQol 5-dimensional questionnaire (EQ5D). The study included 136 participants over a 29-month period. Overall, in-hospital and 6-month mortality occurred in 7 (5%) and 11 (8%) participants, respectively. The composite outcome occurred in 60 (44%). The mean increase in EQ5D summary index at 6 months was 0.10 (standard deviation 0.24, p = 0.01). Perioperative AMI, AKI, or stroke significantly decreased the odds of a clinically meaningful improvement in quality of life (odds ratio 0.32; 95% confidence interval 0.13-0.79; p = 0.014). Preoperative IABC was used in 39 participants and did not predict postoperative outcomes. The study identified a group of patients at risk of LCOS in whom CABG surgery was associated with a substantial burden of perioperative morbidity. Preoperative IABC use was variable, supporting the need for further research. Copyright © 2018 Elsevier Ltd. All rights reserved.

Ballooning for Biologists: Mission Essentials for Flying Experiments on Large NASA Balloons

Science.gov (United States)

Smith, David J.; Sowa, Marianne

2017-01-01

Despite centuries of scientific balloon flights, only a handful of experiments have produced biologically-relevant results. Yet unlike orbital spaceflight, it is much faster and cheaper to conduct biology research with balloons, sending specimens to the near space environment of Earths stratosphere. Samples can be loaded the morning of a launch and sometimes returned to the laboratory within one day after flying. The National Aeronautics and Space Administration (NASA) flies large, unmanned scientific balloons from all over the globe, with missions ranging from hours to weeks in duration. A payload in the middle portion of the stratosphere (approx. 35 km above sea level) will be exposed to an environment similar to the surface of Mars: temperatures generally around -36 C, atmospheric pressure at a thin 1 kPa, relative humidity levels <1%, and a harsh illumination of ultraviolet (UV) and cosmic radiation levels (about 100 W/sq m and 0.1 mGy/d, respectively) that can be obtained nowhere else on the surface of the Earth, including environmental chambers and particle accelerator facilities attempting to simulate space radiation effects. Considering the operational advantages of ballooning and the fidelity of space-like stressors in the stratosphere, researchers in aerobiology, astrobiology, and space biology can benefit from balloon flight experiments as an intermediary step on the extraterrestrial continuum (ground, low Earth orbit, and deep space studies). Our presentation targets biologists with no background or experience in scientific ballooning. We will provide an overview of large balloon operations, biology topics that can be uniquely addressed in the stratosphere, and a roadmap for developing payloads to fly with NASA.

Aortic Annular Enlargement during Aortic Valve Replacement

Directory of Open Access Journals (Sweden)

Selman Dumani

2016-09-01

Full Text Available In the surgery of aortic valve replacement is always attempted, as much as possible, to implant the larger prosthesis with the mains goals to enhance the potential benefits, to minimise transvalvular gradient, decrease left ventricular size and avoid the phenomenon of patient-prosthesis mismatch. Implantation of an ideal prosthesis often it is not possible, due to a small aortic annulus. A variety of aortic annulus enlargement techniques is reported to avoid patient-prosthesis mismatch. We present the case that has submitted four three times open heart surgery. We used Manouguian technique to enlarge aortic anulus with excellent results during the fourth time of surgery.

21 CFR 874.4100 - Epistaxis balloon.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Epistaxis balloon. 874.4100 Section 874.4100 Food... DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4100 Epistaxis balloon. (a) Identification. An epistaxis balloon is a device consisting of an inflatable balloon intended to control internal...

Valve-sparing aortic root replacement and aortic valve repair in a patient with acromegaly and aortic root dilatation

Directory of Open Access Journals (Sweden)

Karel Van Praet

2015-07-01

Full Text Available Aortic regurgitation and dilatation of the aortic root and ascending aorta are severe complications of acromegaly. The current trend for management of an aortic root aneurysm is valve-sparing root replacement as well as restoring the diameter of the aortic sinotubular junction (STJ and annulus. Our case report supports the recommendation that in patients with acromegaly, severe aortic root involvement may indicate the need for surgery.

Launching Garbage-Bag Balloons.

Science.gov (United States)

Kim, Hy

1997-01-01

Presents a modification of a procedure for making and launching hot air balloons made out of garbage bags. Student instructions for balloon construction, launching instructions, and scale diagrams are included. (DDR)

Metabolic and hemodynamic effects of saline infusion to maintain volemia on temporary abdominal aortic occlusion

Directory of Open Access Journals (Sweden)

Fábio Ferreira Amorim

2002-10-01

Full Text Available OBJECTIVE: To analyze hemodynamic and metabolic effects of saline solution infusion in the maintenance of blood volume in ischemia-reperfusion syndrome during temporary abdominal aortic occlusion in dogs. METHODS: We studied 20 dogs divided into 2 groups: the ischemia-reperfusion group (IRG, n=10 and the ischemia-reperfusion group with saline solution infusion aiming at maintaining mean pulmonary arterial wedge pressure between 10 and 20 mmHg (IRG-SS, n=10. All animals were anesthetized with sodium thiopental and maintained on spontaneous ventilation. Occlusion of the supraceliac aorta was obtained with inflation of a Fogarty catheter inserted through the femoral artery. After 60 minutes of ischemia, the balloon was deflated, and the animals were observed for another 60 minutes of reperfusion. RESULTS: IRG-SS dogs did not have hemodynamic instability after aortic unclamping, and the mean systemic blood pressure and heart rate were maintained. However, acidosis worsened, which was documented by a greater reduction of arterial pH that occurred especially due to the absence of a respiratory response to metabolic acidosis that was greater with the adoption of this procedure. CONCLUSION: Saline solution infusion to maintain blood volume avoided hemodynamic instability after aortic unclamping. This procedure, however, caused worsening in metabolic acidosis in this experimental model.

Aortic valve bypass

DEFF Research Database (Denmark)

Lund, Jens T; Jensen, Maiken Brit; Arendrup, Henrik

2013-01-01

In aortic valve bypass (AVB) a valve-containing conduit is connecting the apex of the left ventricle to the descending aorta. Candidates are patients with symptomatic aortic valve stenosis rejected for conventional aortic valve replacement (AVR) or transcatheter aortic valve implantation (TAVI). ...

Correction of aortic insufficiency with an external adjustable prosthetic aortic ring.

Science.gov (United States)

Gogbashian, Andrew; Ghanta, Ravi K; Umakanthan, Ramanan; Rangaraj, Aravind T; Laurence, Rita G; Fox, John A; Cohn, Lawrence H; Chen, Frederick Y

2007-09-01

Less invasive, valve-sparing options are needed for patients with aortic insufficiency (AI). We sought to evaluate the feasibility of reducing AI with an external adjustable aortic ring in an ovine model. To create AI, five sheep underwent patch plasty enlargement of the aortic annulus and root by placement of a 10 x 15 mm pericardial patch between the right and noncoronary cusps. An adjustable external ring composed of a nylon band was fabricated and placed around the aortic root. Aortic flow, aortic pressure, and left ventricular pressures were measured with the ring loose (off) and tightened (on). Mean regurgitant orifice area decreased by 86%, from 0.07 +/- 0.03 cm2 (ring loose, off) to 0.01 +/- 0.00 cm2 (ring tightened, on) [p < 0.01]. The regurgitant fraction decreased from 18 +/- 4% to 2 +/- 1% [p < 0.01]. The ring did not significantly affect stroke volume and aortic pressure. An ovine model of aortic root dilatation resulting in acute AI has been developed. In this model, application of an external, adjustable constricting aortic ring eliminated AI. An aortic ring may be a useful adjunct in reducing AI secondary to annular dilatation.

Aortic compliance in patients with aortic regurgitation. Evaluation with magnetic resonance imaging

International Nuclear Information System (INIS)

Murai, Sachiko; Hamada, Seiki; Ueguchi, Takashi

2005-01-01

The purpose of this study was to assess by means of cine magnetic resonance imaging (MRI) aortic compliance before and after aortic valve replacement (AVR with SJM (St. Jude Medical, St paul, MN) valve) in patients with aortic regurgitation (AR). Two groups (healthy controls and patients with severe isolated AR) of 10 subjects each were included in this study. Cine MRI was performed at three locations of the aorta, and aortic compliance was calculated by dividing the maximum change in the aortic area by pulse pressure. Cine MRI is useful to assess abnormalities of aortic compliance in patients with AR. Compared with the control group, aortic compliance in the AR group was significantly less in the ascending aorta (p<0.05), decreasing in order of aortic location. After AVR, aortic compliance improved for all locations. Cine MRI enables assessment of aortic biophysical properties such as a compliance for evaluating the progression of AR and the efficacy of treatment. (author)

Acute Type II Aortic Dissection with Severe Aortic Regurgitation and Chronic Descending Aortic Dissection in Pregnant Patient with Marfan Syndrome.

Science.gov (United States)

Lee, Seok-Soo; Jung, Tae-Eun; Lee, Dong Hyup

2012-12-01

Aortic dilatation and dissection are severe complications during pregnancy that can be fatal to both the mother and the fetus. The risks of these complications are especially high in pregnant patients with Marfan syndrome; however, incidents of descending aortic dissection are very rare. This case report involves a successful Bentall procedure for and recovery from a rare aortic dissection in a pregnant Marfan patient who developed acute type II aortic dissection with severe aortic regurgitation and chronic descending aortic dissection immediately after Cesarean section. Regular follow-up will be needed to monitor the descending aortic dissection.

Aortic root replacement after previous surgical intervention on the aortic valve, aortic root, or ascending aorta.

Science.gov (United States)

Kirsch, E W Matthias; Radu, N Costin; Mekontso-Dessap, Armand; Hillion, Marie-Line; Loisance, Daniel

2006-03-01

Aortic root replacement after a previous operation on the aortic valve, aortic root, or ascending aorta remains a major challenge. Records of 56 consecutive patients (44 men; mean age, 56.4 +/- 13.6 years) undergoing reoperative aortic root replacement between June 1994 and June 2005 were reviewed retrospectively. Reoperation was performed 9.4 +/- 6.7 years after the last cardiac operation. Indications for reoperation were true aneurysm (n = 14 [25%]), false aneurysm (n = 10 [18%]), dissection or redissection (n = 9 [16%]), structural or nonstructural valve dysfunction (n = 10 [18%]), prosthetic valve-graft infection (n = 12 [21%]), and miscellaneous (n = 1 [2%]). Procedures performed were aortic root replacement (n = 47 [84%]), aortic root replacement plus mitral valve procedure (n = 5 [9%]), and aortic root replacement plus arch replacement (n = 4 [7%]). In 14 (25%) patients coronary artery bypass grafting had to be performed unexpectedly during the same procedure or immediately after the procedure to re-establish coronary perfusion. Hospital mortality reached 17.9% (n = 10). Multivariate logistic regression analysis revealed the need for unplanned perioperative coronary artery bypass grafting as the sole independent risk factor for hospital death (P = .005). Actuarial survival was 83.8% +/- 4.9% at 1 month, 73.0% +/- 6.3% at 1 year, and 65.7% +/- 9.0% at 5 years after the operation. One patient had recurrence of endocarditis 6.7 months after the operation and required repeated homograft aortic root replacement. Reoperative aortic root replacement remains associated with a high postoperative mortality. The need to perform unplanned coronary artery bypass grafting during reoperative aortic root replacement is a major risk factor for hospital death. The optimal technique for coronary reconstruction in this setting remains to be debated.

JACEE long duration balloon flights

International Nuclear Information System (INIS)

Burnett, T.; Iwai, J.; Lord, J.J.; Strausz, S.; Wilkes, R.J.; Dake, S.; Oda, H.; Miyamura, O.; Fuki, M.; Jones, W.V.; Gregory, J.; Hayashi, T.; Takahashi, U.; Tominaga, Y.; Wefel, J.P.; Fountain, W.; Derrickson, J.; Parnell, T.A.; Roberts, E.; Tabuki, T.; Watts, J.W.

1989-01-01

JACEE balloon-borne emulsion chamber detectors are used to observe the spectra and interactions of cosmic ray protons and nuclei in the energy range 1-100A TeV. Experience with long duration mid-latitude balloon flights and characteristics of the detector system that make it ideal for planned Antarctic balloon flights are discussed. 5 refs., 2 figs

Fasting and meal-suppressed ghrelin levels before and after intragastric balloons and balloon-induced weight loss

NARCIS (Netherlands)

Mathus-Vliegen, E. M. H.; Eichenberger, R. I.

2014-01-01

Intragastric balloons may be an option for obese patients with weight loss failure. Its mode of action remains enigmatic. We hypothesised depressed fasting ghrelin concentrations and enhanced meal suppression of ghrelin secretion by the gastric fundus through balloon contact and balloon-induced

Technologies developed by CNES balloon team

Science.gov (United States)

Sosa-Sesma, Sergio; Charbonnier, Jean-Marc; Deramecourt, Arnaud

CNES balloon team develops and operates all the components of this kind of vehicle: it means envelope and gondola. This abstract will point out only developments done for envelope. Nowadays CNES offers to scientists four types of envelops that cover a large range of mission demands. These envelops are: 1. Zero pressure balloons: Size going from 3,000m3 to 600,000m3, this kind of envelop is ideal for short duration flights (a few hours) but if we use an intelligent management of ballast consumption and if we chose the best launch site, it is possible to perform medium duration flights (10/20 days depending on the ballast on board). Flight train mass starts at 50kg for small balloons and reach 1000kg for larger ones. Zero pressure balloons are inflated with helium gas. 2. Super pressure balloons: Diameter going from 2.5m to 12m, this kind of envelop is ideal for long duration flights (1 to 6 months). Flight train is inside the envelop for small balloons, it means 2.5 diameter meters which is usually called BPCL (Super pressure balloon for Earth boundary layer) and it is about 3kg of mass. Larger ones could lift external flight trains about 50kg of mass. Super pressure balloons are inflated with helium gas. 3. MIR balloons: Size going from 36,000m3 to 46,000m3. Ceiling is reach with helium gas but after three days helium is no longer present inside and lift force is produced by difference of temperature between air inside and air of atmosphere. Flight trains must not be over 50kg. 4. Aero Clipper balloons: A concept to correlate measurements done in oceans and in nearest layers of atmosphere simultaneously. Flight train is made by a "fish" that drags inside water and an atmospheric gondola few meters above "fish", both pushed by a balloon which profits of the wind force. Materials used for construction and assembling depend on balloon type; they are usually made of polyester or polyethylene. Thickness varies from 12 micrometers to 120 micrometers. Balloon assembling

Sequential transcatheter aortic valve implantation due to valve dislodgement - a Portico valve implanted over a CoreValve bioprosthesis.

Science.gov (United States)

Campante Teles, Rui; Costa, Cátia; Almeida, Manuel; Brito, João; Sondergaard, Lars; Neves, José P; Abecasis, João; M Gabriel, Henrique

2017-03-01

Transcatheter aortic valve implantation (TAVI) has become an important treatment in high surgical risk patients with severe aortic stenosis (AS), whose complications need to be managed promptly. The authors report the case of an 86-year-old woman presenting with severe symptomatic AS, rejected for surgery due to advanced age and comorbidities. The patient underwent a first TAVI, with implantation of a Medtronic CoreValve ® , which became dislodged and migrated to the ascending aorta. Due to the previous balloon valvuloplasty, the patient's AS became moderate, and her symptoms improved. After several months, she required another intervention, performed with a St. Jude Portico ® repositionable self-expanding transcatheter aortic valve. There was a good clinical response that was maintained at one-year follow-up. The use of a self-expanding transcatheter bioprosthesis with repositioning features is a solution in cases of valve dislocation to avoid suboptimal positioning of a second implant, especially when the two valves have to be positioned overlapping or partially overlapping each other. Copyright © 2017 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

Oxidative inhibition of the vascular Na+-K+ pump via NADPH oxidase-dependent β1-subunit glutathionylation: implications for angiotensin II-induced vascular dysfunction.

Science.gov (United States)

Liu, Chia-Chi; Karimi Galougahi, Keyvan; Weisbrod, Robert M; Hansen, Thomas; Ravaie, Ramtin; Nunez, Andrea; Liu, Yi B; Fry, Natasha; Garcia, Alvaro; Hamilton, Elisha J; Sweadner, Kathleen J; Cohen, Richard A; Figtree, Gemma A

2013-12-01

Glutathionylation of the Na(+)-K(+) pump's β1-subunit is a key molecular mechanism of physiological and pathophysiological pump inhibition in cardiac myocytes. Its contribution to Na(+)-K(+) pump regulation in other tissues is unknown, and cannot be assumed given the dependence on specific β-subunit isoform expression and receptor-coupled pathways. As Na(+)-K(+) pump activity is an important determinant of vascular tone through effects on [Ca(2+)]i, we have examined the role of oxidative regulation of the Na(+)-K(+) pump in mediating angiotensin II (Ang II)-induced increases in vascular reactivity. β1-subunit glutathione adducts were present at baseline and increased by exposure to Ang II in rabbit aortic rings, primary rabbit aortic vascular smooth muscle cells (VSMCs), and human arterial segments. In VSMCs, Ang II-induced glutathionylation was associated with marked reduction in Na(+)-K(+)ATPase activity, an effect that was abolished by the NADPH oxidase inhibitory peptide, tat-gp91ds. In aortic segments, Ang II-induced glutathionylation was associated with decreased K(+)-induced vasorelaxation, a validated index of pump activity. Ang II-induced oxidative inhibition of Na(+)-K(+) ATPase and decrease in K(+)-induced relaxation were reversed by preincubation of VSMCs and rings with recombinant FXYD3 protein that is known to facilitate deglutathionylation of β1-subunit. Knock-out of FXYD1 dramatically decreased K(+)-induced relaxation in a mouse model. Attenuation of Ang II signaling in vivo by captopril (8 mg/kg/day for 7 days) decreased superoxide-sensitive DHE levels in the media of rabbit aorta, decreased β1-subunit glutathionylation, and enhanced K(+)-induced vasorelaxation. Ang II inhibits the Na(+)-K(+) pump in VSMCs via NADPH oxidase-dependent glutathionylation of the pump's β1-subunit, and this newly identified signaling pathway may contribute to altered vascular tone. FXYD proteins reduce oxidative inhibition of the Na(+)-K(+) pump and may have an

Delayed Presentation of a Giant Ascending Aortic Aneurysm following Aortic Valve Replacement

Directory of Open Access Journals (Sweden)

Tugrul Göncü

2009-01-01

Full Text Available Giant ascending aortic aneurysm formation following aortic valve replacement is rare. A 28-year-old man who underwent aortic valve replacement with a prosthetic valve for aortic regurgitation secondary to congenital bicuspid aortic valve about 10 years ago was diagnosed with a giant ascending aortic aneurysm about 16 cm in diameter in follow-up. The aneurysm was resected leaving the functional old mechanical prosthesis in place and implanted a 34-mm Hemashield woven graft, associated with the left and right coronary artery button implantation. Histological findings of the aortic aneurysm wall showed cystic medial necrosis. The postoperative course was uneventful and postoperative examination demonstrated good surgical results.

Two Tethered Balloon Systems

Science.gov (United States)

Youngbluth, Otto; Owens, Thomas L.; Storey, Richard W.

1990-01-01

Systems take meteorological measurements for variety of research projects. Report describes work done by NASA Langley Research Center in atmospheric research using tethered balloon systems composed of commercially available equipment. Two separate tethered balloon systems described in report have payloads and configurations tailored to requirements of specific projects. Each system capable of measuring atmospheric parameter or species in situ and then telemetering this data in real time to ground station. Meteorological data and concentration of ozone typically measured. Indicates instrumented tethered balloon systems have distinct advantages over other systems for gathering data on troposphere.

Recent Developments in Scientific Research Ballooning

International Nuclear Information System (INIS)

Jones, W. Vernon

2007-01-01

The National Aeronautics and Space Administration (NASA) Balloon Program is committed to meeting the need for extended duration scientific investigations by providing advanced balloon vehicles and support systems. A sea change in ballooning capability occurred with the inauguration of 8 - 20 day flights around Antarctica in the early 1990's. The attainment of 28-31 day flights and a record-breaking 42-day flight in, respectively, two and three circumnavigations of the continent has greatly increased the expectations of the scientific users. A new super-pressure balloon is currently under development for future flights of 60-100 days at any latitude, which would bring another sea change in scientific research ballooning

Pioneering Space Research with Balloons

Science.gov (United States)

Jones, W. V.

NASA s Scientific Ballooning Planning Team has concluded that ballooning enables significant scientific discoveries while providing test beds for space instruments and training for young scientists Circumpolar flights around Antarctica have been spectacularly successful with fight durations up to 42 days Demand for participation in this Long-Duration Balloon LDB program a partnership with the U S National Science Foundation Office of Polar Programs is greater than the current capacity of two flights per campaign Given appropriate international agreements LDB flights in the Northern Hemisphere would be competitive with Antarctic flights and super-pressure balloons would allow comparable flights at any latitude The Balloon Planning Team made several recommendations for LDB flights provide a reliable funding source for sophisticated payloads extend the Antarctic capability to three flights per year and develop a comparable capability in the Arctic provide aircraft for intact-payload recovery develop a modest trajectory modification capability to enable longer flights and enhance super-pressure balloons to carry 1-ton payloads to 38 km Implementation of these recommendations would facilitate frequent access to near-space for cutting-edge research and technology development for a wide range of investigations

Development of a New Coaxial Balloon Catheter System for Balloon-Occluded Retrograde Transvenous Obliteration (B-RTO)

International Nuclear Information System (INIS)

Tanoue, Shuichi; Kiyosue, Hiro; Matsumoto, Shunro; Hori, Yuzo; Okahara, Mika; Kashiwagi, Junji; Mori, Hiromu

2006-01-01

Purpose. To develop a new coaxial balloon catheter system and evaluate its clinical feasibility for balloon-occluded retrograde transvenous obliteration (B-RTO). Methods. A coaxial balloon catheter system was constructed with 9 Fr guiding balloon catheter and 5 Fr balloon catheter. A 5 Fr catheter has a high flexibility and can be coaxially inserted into the guiding catheter in advance. The catheter balloons are made of natural rubber and can be inflated to 2 cm (guiding) and 1 cm (5 Fr) maximum diameter. Between July 2003 and April 2005, 8 consecutive patients (6 men, 2 women; age range 33-72 years, mean age 55.5 years) underwent B-RTO using the balloon catheter system. Five percent ethanolamine oleate iopamidol (EOI) was used as sclerosing agent. The procedures, including maneuverability of the catheter, amount of injected sclerosing agent, necessity for coil embolization of collateral draining veins, and initial clinical results, were evaluated retrospectively. The occlusion rate was assessed by postcontrast CT within 2 weeks after B-RTO. Results. The balloon catheter could be advanced into the proximal potion of the gastrorenal shunt beyond the collateral draining vein in all cases. The amount of injected EOI ranged from 3 to 34 ml. Coil embolization of the collateral draining vein was required in 2 cases. Complete obliteration of gastric varices on initial follow-up CT was obtained in 7 cases. The remaining case required re-treatment that resulted in complete obstruction of the varices after the second B-RTO. No procedure-related complications were observed. Conclusion. B-RTO using the new coaxial balloon catheter is feasible. Gastric varices can be treated more simply by using this catheter system

Complications of balloon packing in epistaxis

NARCIS (Netherlands)

Vermeeren, Lenka; Derks, Wynia; Fokkens, Wytske; Menger, Dirk Jan

2015-01-01

Although balloon packing appears to be efficient to control epistaxis, severe local complications can occur. We describe four patients with local lesions after balloon packing. Prolonged balloon packing can cause damage to nasal mucosa, septum and alar skin (nasal mucosa, the cartilaginous skeleton

The bicuspid aortic valve and its relation to aortic dilation

Directory of Open Access Journals (Sweden)

Shi-Min Yuan

2010-01-01

Full Text Available BACKGROUND: A bicuspid aortic valve (BAV is a common congenital heart disease, which affects 1-2% of the population. However, the relationship between BAVs and aortic dilation has not been sufficiently elucidated. METHODS: A total of 241 BAV patients who were referred to this hospital for cardiac surgey over a 4.75-year period were included in this study. In addition to the clinical characteristics of the included patients, the morphological features of the aortic valve and aorta, the length of the left main coronary artery, and the laboratory findings (the coagulation and hematological parameters as well as the total cholesterol concentration were determined and compared with those of the tricuspid aortic valve (TAV patients. RESULTS: The BAV patients were younger than the TAV patients for a valve surgery in the last 3 months of the study period. The BAV patients were predominantly male. Most of the BAVs that were surgically treated were stenotic, regurgitant, or combined, and only 19 (7.88% were normally functioning valves. According to echocardiography or operative records, 148 (78.31% were type A, 31 (16.40% were type B, and 10 (5.29% were type C. The left main coronary artery was much shorter in the BAV patients than it was in the TAV patients. There was no significant difference between BAV and TAV patients in the total cholesterol concentrations; whereas differences were noted between patients receiving lipid-lowering therapy and those not receiving lipid-lowering therapy. The dimensions of the aortic root, sinotubular junction, and ascending aorta were beyond normal limits, while they were significantly smaller in the BAV patients than in the TAV patients. They were also much smaller in patients receiving statin therapy than those not receiving statin therapy in both groups. Moreover, the aortic dilation in the BAV group was found to be significantly associated with patient age. CONCLUSIONS: The BAV patients developed aortic wall and

Aortic root reimplantation procedure: a new milestone in aortic valve-sparing operations

Directory of Open Access Journals (Sweden)

А. М. Чернявский

2016-08-01

Full Text Available Aim: Emphasis in this study was placed on clinical and functional assessment of a modified "Florida Sleeve" procedure during surgical correction of ascending aorta aneurysms with concomitant aortic insufficiency.Methods: 32 patients with an aneurysm of the ascending aorta and aortic insufficiency underwent a modified "Florida Sleeve" procedure. The average follow-up was 17 (0-60 months. The average age of patients was 57±13 (23-73 years 56±13 years.Results: The expected 4-year cumulative survival rate was 84.3%. Overall freedom from aortic insufficiency in the late period was 88.9%. Median aortic regurgitation was 1+ (1; 2. Long-term follow-up revealed no valve-associated complications.Conclusion: The aortic root reimplantation procedure enables optimal correction of the existing lesions of the aortic root without performing aortic valve replacement and demonstrates stable clinical and functional outcomes in the long-term period.Key words: aortic aneurysm; aortic valve; valve-sparing operations.FundingThe study had no sponsorship.Conflict of interestThe authors declare no conflict of interest.

Acute Type II Aortic Dissection with Severe Aortic Regurgitation and Chronic Descending Aortic Dissection in Pregnant Patient with Marfan Syndrome

OpenAIRE

Lee, Seok-Soo; Jung, Tae-Eun; Lee, Dong Hyup

2012-01-01

Aortic dilatation and dissection are severe complications during pregnancy that can be fatal to both the mother and the fetus. The risks of these complications are especially high in pregnant patients with Marfan syndrome; however, incidents of descending aortic dissection are very rare. This case report involves a successful Bentall procedure for and recovery from a rare aortic dissection in a pregnant Marfan patient who developed acute type II aortic dissection with severe aortic regurgitat...

Aortic valve replacement for aortic stenosis caused by alkaptonuria.

Science.gov (United States)

Hiroyoshi, Junko; Saito, Aya; Panthee, Nirmal; Imai, Yasushi; Kawashima, Dai; Motomura, Noboru; Ono, Minoru

2013-03-01

We report a case of aortic stenosis associated with ochronosis in a 70-year-old man who underwent biologic aortic valve replacement. Intraoperative findings included ochronosis of a severely calcified pigmented aortic valve along with pigmentation of the intima of the aorta. Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Modelling Hot Air Balloons.

Science.gov (United States)

Brimicombe, M. W.

1991-01-01

A macroscopic way of modeling hot air balloons using a Newtonian approach is presented. Misleading examples using a car tire and the concept of hot air rising are discussed. Pressure gradient changes in the atmosphere are used to explain how hot air balloons work. (KR)

Surgery for acute Type I aortic dissection without resection of supra-aortic entry sites leads to unfavourable aortic remodelling.

Science.gov (United States)

Heo, Woon; Song, Suk-Won; Lee, Kwang-Hun; Lee, Shin-Young; Kim, Tae-Hoon; Baek, Min-Young; Yoo, Kyung-Jong

2018-01-29

This study aimed to evaluate the impact of remnant re-entries in arch branches on postoperative change in the aortic arch and descending aortic diameters and the rate of major adverse aortic events. Between January 2010 and December 2016, 249 patients underwent surgery for acute Type I aortic dissection. Patients who underwent total arch replacement, had Marfan syndrome or had intramural haematoma were excluded. Seventy-two patients with predischarge and follow-up computed tomography scans were enrolled. Patients with and without re-entries in the arch branches after surgery were assigned to the supra-aortic entry (SAE, n = 21) and no supra-aortic entry (n = 51) groups, respectively. Diameters were measured at 7 levels: the innominate artery, left common carotid artery, left subclavian artery, 20 mm distal to the left subclavian artery, pulmonary artery bifurcation, coeliac axis and maximal diameter of the descending thoracic aorta. Growth rates at the levels of the pulmonary artery bifurcation and 20 mm distal to the left subclavian artery were significantly higher in the SAE group than in the no supra-aortic entry group. The rate of freedom from major adverse aortic events (annual growth >5 mm or maximal diameter of the descending thoracic aorta >50 mm) at 5 years was significantly higher in the no supra-aortic entry group than in the SAE group. Remnant SAE leads to unfavourable aortic remodelling after acute Type I aortic dissection repair. © The Author(s) 2018. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Solar research with stratospheric balloons

Science.gov (United States)

Vázquez, Manuel; Wittmann, Axel D.

Balloons, driven by hot air or some gas lighter than air, were the first artificial machines able to lift payloads (including humans) from the ground. After some pioneering flights the study of the physical properties of the terrestrial atmosphere constituted the first scientific target. A bit later astronomers realized that the turbulence of the atmospheric layers above their ground-based telescopes deteriorated the image quality, and that balloons were an appropriate means to overcome, total or partially, this problem. Some of the most highly-resolved photographs and spectrograms of the sun during the 20th century were actually obtained by balloon-borne telescopes from the stratosphere. Some more recent projects of solar balloon astronomy will also be described.

Abdominal cavity balloon for preventing a patient's bleeding

OpenAIRE

Naber, E.E.H.; Rutten, H.J.T.; Jakimowicz, J.J.; Goossens, R.H.M.; Moes, C.C.M.; Buzink, S.N.

2007-01-01

The invention relates to an abdominal cavity balloon for preventing a haemorrhage in a patient's pelvic region, comprising an inflatable balloon, wherein the balloon is pro vided with a smooth surface and with a strip that is flex- urally stiff and formed to follow the balloon's shape for po sitioning the balloon.

Acute Aortic Arch Perforation During Transcatheter Aortic Valve Replacement in Bicuspid Aortic Stenosis and a Gothic Aortic Arch

DEFF Research Database (Denmark)

Millan-Iturbe, Oscar; Sawaya, Fadi J.; Bieliauskas, Gintautas

2017-01-01

AS because of its unique anatomic features. This case report describes an acute aortic perforation during delivery of a transcatheter heart valve to treat a severe bicuspid AS with a “gothic aortic arch”; more careful evaluation of the preprocedural multislice computed tomographic scan would have unveiled...

Calculating Payload for a Tethered Balloon System

Science.gov (United States)

Charles D. Tangren

1980-01-01

A graph method to calculate payload for a tethered balloon system, with the supporting helium lift and payload equations. is described. The balloon system is designed to collect emissions data during the convective-lift and no-convective-lift phases of a forest fire. A description of the balloon system and a list of factors affecting balloon selection are included....

Ballooning stable high beta tokamak equilibria

International Nuclear Information System (INIS)

Tuda, Takashi; Azumi, Masafumi; Kurita, Gen-ichi; Takizuka, Tomonori; Takeda, Tatsuoki

1981-04-01

The second stable regime of ballooning modes is numerically studied by using the two-dimensional tokamak transport code with the ballooning stability code. Using the simple FCT heating scheme, we find that the plasma can locally enter this second stable regime. And we obtained equilibria with fairly high beta (β -- 23%) stable against ballooning modes in a whole plasma region, by taking into account of finite thermal diffusion due to unstable ballooning modes. These results show that a tokamak fusion reactor can operate in a high beta state, which is economically favourable. (author)

Scientific ballooning. Proceedings of the symposium on the scientific use of balloons and related technical problems, Innsbruck, Austria, May 29-June 10, 1978

Energy Technology Data Exchange (ETDEWEB)

Riedler, W

1979-01-01

The book includes works on operational and technical aspects of balloon launching I and II, cooperative balloon campaigns, and new developments in scientific use of balloons. The specific topics discussed are coordinated balloon and rocket measurements of stratospheric wind shears and turbulence, ballooning in Japan and India, magnetospheric processes investigated with data taken from balloon flights, and remote sensing of middle atmosphere winds from balloon platforms.

In vitro analysis of balloon cuffing phenomenon: inherent biophysical properties of catheter material or mechanics of catheter balloon deflation?

Science.gov (United States)

Chung, Eric; So, Karina

2012-06-01

To investigates the different methods of balloon deflation, types of urinary catheters and exposure to urine media in catheter balloon cuffing. Bardex®, Bard-Lubri-Sil®, Argyle®, Releen® and Biocath® were tested in sterile and E.Coli inoculated urine at 0, 14 and 28 days. Catheter deflation was performed with active deflation; passive deflation; passive auto-deflation; and excision of the balloon inflow channel. Balloon cuffing was assessed objectively by running the deflated balloon over a plate of agar and subjectively by 3 independent observers. Bardex®, Argyle® and Biocath® showed greater degree of catheter balloon cuffing (p deflation was the worst method (p 0.05). Linear regression model analysis confirmed time as the most significant factor. The duration of catheters exposure, different deflation methods and types of catheters tested contributed significantly to catheter balloon cuffing (p < 0.01).

Flight Qualification of the NASA's Super Pressure Balloon

Science.gov (United States)

Cathey, Henry; Said, Magdi; Fairbrother, Debora

Designs of new balloons to support space science require a number of actual flights under various flight conditions to qualify them to as standard balloon flight offerings to the science community. Development of the new Super Pressure Balloon for the National Aeronautics and Space Administration’s Balloon Program Office has entailed employing new design, analysis, and production techniques to advance the state of the art. Some of these advances have been evolutionary steps and some have been revolutionary steps requiring a maturing understanding of the materials, designs, and manufacturing approaches. The NASA Super Pressure Balloon development end goal is to produce a flight vehicle that is qualified to carry a ton of science instrumentation, at an altitude greater than 33 km while maintaining a near constant pressure altitude for extended periods of up to 100 days, and at any latitude on the globe. The NASA’s Balloon Program Office has pursued this development in a carefully executed incremental approach by gradually increasing payload carrying capability and increasing balloon volume to reach these end goal. A very successful test flight of a ~200,700 m3 balloon was launch in late 2008 from Antarctica. This balloon flew for over 54 days at a constant altitude and circled the Antarctic continent almost three times. A larger balloon was flown from Antarctica in early 2011. This ~422,400 m3 flew at a constant altitude for 22 days making one circuit around Antarctica. Although the performance was nominal, the flight was terminated via command to recover high valued assets from the payload. The balloon designed to reach the program goals is a ~532,200 m3 pumpkin shaped Super Pressure Balloon. A test flight of this balloon was launched from the Swedish Space Corporation’s Esrange Balloon Launch Facilities near Kiruna, Sweden on 14 August, 2012. This flight was another success for this development program. Valuable information was gained from this short test

Esophageal achalasia : results of balloon dilation

Energy Technology Data Exchange (ETDEWEB)

Ki, Won Woo; Kang, Sung Gwon; Yoon, Kwon Ha; Kim, Nam Hyeon; Lee, Hyo Jeong; Yoon, Hyun Ki; Sung, Kyu Bo; Song, Ho Young [Ulsan Univ. College of Medicine, Seoul (Korea, Republic of)

1996-08-01

To evaluate the clinical effectiveness of fluoroscopically guided balloon dilation in the treatment of esophageal achalasia. Under fluoroscopic guidance, 21 balloon dilation procedures were performed in 14 patients with achalasia. A balloon with a diameter of 20 mm was used for the initial attempt.If the patient tolerated this well, the procedure was repeated with a 10-20 mm balloon, placed alongside at the same session. If, however the patient complained of severe chest pain and/or a postprocedural esophagogram showed an improvement,the additional balloon was not used. For patients whose results were unsatisfactory, the dilation procedure was repeated at sessions three to seven days apart. Succesful dilation was achieved in 13 of 14 patients(92.9%), who needed a total of 20 sessions of balloon dilation, ranging from one to three sessions per patient(mean, 1.54 sessions). Esophageal rupture occured in one of 14 patients(7.1%) ; of the 13 patients who underwent a successful dilation procedure, 12(92.3%) were free of recurrent symptoms during the follow-up period of 1-56(mean, 18.5) months. The remaning patient(7.7%) had a recurrence seven months after dilation. Fluoroscopically guided balloon dilation seems to be safe and effective in the treatment of esophageal achalasia.

Esophageal achalasia : results of balloon dilation

International Nuclear Information System (INIS)

Ki, Won Woo; Kang, Sung Gwon; Yoon, Kwon Ha; Kim, Nam Hyeon; Lee, Hyo Jeong; Yoon, Hyun Ki; Sung, Kyu Bo; Song, Ho Young

1996-01-01

To evaluate the clinical effectiveness of fluoroscopically guided balloon dilation in the treatment of esophageal achalasia. Under fluoroscopic guidance, 21 balloon dilation procedures were performed in 14 patients with achalasia. A balloon with a diameter of 20 mm was used for the initial attempt.If the patient tolerated this well, the procedure was repeated with a 10-20 mm balloon, placed alongside at the same session. If, however the patient complained of severe chest pain and/or a postprocedural esophagogram showed an improvement,the additional balloon was not used. For patients whose results were unsatisfactory, the dilation procedure was repeated at sessions three to seven days apart. Succesful dilation was achieved in 13 of 14 patients(92.9%), who needed a total of 20 sessions of balloon dilation, ranging from one to three sessions per patient(mean, 1.54 sessions). Esophageal rupture occured in one of 14 patients(7.1%) ; of the 13 patients who underwent a successful dilation procedure, 12(92.3%) were free of recurrent symptoms during the follow-up period of 1-56(mean, 18.5) months. The remaning patient(7.7%) had a recurrence seven months after dilation. Fluoroscopically guided balloon dilation seems to be safe and effective in the treatment of esophageal achalasia

The use of transcatheter aortic valve replacement vs surgical aortic valve replacement for the treatment of aortic stenosis

Directory of Open Access Journals (Sweden)

Jensen HA

2015-08-01

Full Text Available Hanna A Jensen, Lillian L Tsai, Vinod H Thourani Division of Cardiothoracic Surgery, Joseph B Whitehead Department of Surgery, Structural Heart and Valve Center, Emory University School of Medicine, Atlanta, GA, USA Abstract: Severe aortic stenosis (AS is associated with considerable morbidity and mortality and is increasing in prevalence as the global population increases. Since AS primarily affects the elderly, many of these patients have comorbidities that make them poor candidates for the gold standard treatment for AS, surgical aortic valve replacement. Transcatheter aortic valve replacement has emerged as a novel technology for the management of AS in higher risk patients over the past decade. Randomized trials have established the safety and efficacy of transcatheter aortic valve replacement, and the medical community has rallied to identify the patients who are most suitable for this transformative treatment. This review focuses on outlining the key procedural differences, describing the unique challenges of both operations, and finally assessing and comparing outcomes both on a general level and in challenging patient subgroups. Keywords: aortic valve replacement, transcatheter aortic valve replacement, surgical aortic valve replacement 

Early Cosmic Ray Research with Balloons

Energy Technology Data Exchange (ETDEWEB)

Walter, Michael, E-mail: michael.walter@desy.de

2013-06-15

The discovery of cosmic rays by Victor Hess during a balloon flight in 1912 at an altitude of 5350 m would not have been possible without the more than one hundred years development of scientific ballooning. The discovery of hot air and hydrogen balloons and their first flights in Europe is shortly described. Scientific ballooning was mainly connected with activities of meteorologists. It was also the geologist and meteorologist Franz Linke, who probably observed first indications of a penetrating radiation whose intensity seemed to increase with the altitude. Karl Bergwitz and Albert Gockel were the first physicists studying the penetrating radiation during balloon flights. The main part of the article deals with the discovery of the extraterrestrial radiation by V. Hess and the confirmation by Werner Kolhörster.

Early Cosmic Ray Research with Balloons

Science.gov (United States)

Walter, Michael

2013-06-01

The discovery of cosmic rays by Victor Hess during a balloon flight in 1912 at an altitude of 5350 m would not have been possible without the more than one hundred years development of scientific ballooning. The discovery of hot air and hydrogen balloons and their first flights in Europe is shortly described. Scientific ballooning was mainly connected with activities of meteorologists. It was also the geologist and meteorologist Franz Linke, who probably observed first indications of a penetrating radiation whose intensity seemed to increase with the altitude. Karl Bergwitz and Albert Gockel were the first physicists studying the penetrating radiation during balloon flights. The main part of the article deals with the discovery of the extraterrestrial radiation by V. Hess and the confirmation by Werner Kolhörster.

Early Cosmic Ray Research with Balloons

International Nuclear Information System (INIS)

Walter, Michael

2013-01-01

The discovery of cosmic rays by Victor Hess during a balloon flight in 1912 at an altitude of 5350 m would not have been possible without the more than one hundred years development of scientific ballooning. The discovery of hot air and hydrogen balloons and their first flights in Europe is shortly described. Scientific ballooning was mainly connected with activities of meteorologists. It was also the geologist and meteorologist Franz Linke, who probably observed first indications of a penetrating radiation whose intensity seemed to increase with the altitude. Karl Bergwitz and Albert Gockel were the first physicists studying the penetrating radiation during balloon flights. The main part of the article deals with the discovery of the extraterrestrial radiation by V. Hess and the confirmation by Werner Kolhörster

Altered aortic shape in bicuspid aortic valve relatives influences blood flow patterns.

Science.gov (United States)

Schnell, Susanne; Smith, Danielle A; Barker, Alex J; Entezari, Pegah; Honarmand, Amir R; Carr, Maria L; Malaisrie, S Chris; McCarthy, Patrick M; Collins, Jeremy; Carr, James C; Markl, Michael

2016-11-01

Bicuspid aortic valve (BAV) is known to exhibit familial inheritance and is associated with aortopathy and altered aortic haemodynamics. However, it remains unclear whether BAV-related aortopathy can be inherited independently of valve morphology. Four-dimensional flow magnetic resonance imaging for the in vivo assessment of thoracic aortic 3D blood flow was performed in 24 BAV relatives with trileaflet aortic valves (age = 40 ± 14 years) and 15 healthy controls (age = 37 ± 10 years). Data analysis included aortic dimensions, shape (round/gothic/cubic), and 3D blood flow characteristics (semi-quantitative vortex/helix grading and peak velocities). Cubic and gothic aortic shapes were markedly more prevalent in BAV relatives compared with controls (38 vs. 7%). Ascending aorta (AAo) vortex flow in BAV relatives was significantly increased compared with controls (grading = 1.5 ± 1.0 vs. 0.6 ± 0.9, P = 0.015). Aortic haemodynamics were influenced by aortic shape: peak velocities were reduced for gothic aortas vs. round aortas (P = 0.003); vortex flow was increased for cubic aortas in the AAo (P gothic aortas in the AAo and descending aorta (P = 0.003, P = 0.029). Logistic regression demonstrated significant associations of shape with severity of vortex flow in AAo (P < 0.001) and aortic arch (P = 0.016) in BAV relatives. BAV relatives expressed altered aortic shape and increased vortex flow despite the absence of valvular disease or aortic dilatation. These data suggest a heritable component of BAV-related aortopathy affecting aortic shape and aberrant blood flow, independent of valve morphology. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Fluid Dynamics in Rotary Piston Blood Pumps.

Science.gov (United States)

Wappenschmidt, Johannes; Sonntag, Simon J; Buesen, Martin; Gross-Hardt, Sascha; Kaufmann, Tim; Schmitz-Rode, Thomas; Autschbach, Ruediger; Goetzenich, Andreas

2017-03-01

Mechanical circulatory support can maintain a sufficient blood circulation if the native heart is failing. The first implantable devices were displacement pumps with membranes. They were able to provide a sufficient blood flow, yet, were limited because of size and low durability. Rotary pumps have resolved these technical drawbacks, enabled a growing number of mechanical circulatory support therapy and a safer application. However, clinical complications like gastrointestinal bleeding, aortic insufficiency, thromboembolic complications, and impaired renal function are observed with their application. This is traced back to their working principle with attenuated or non-pulsatile flow and high shear stress. Rotary piston pumps potentially merge the benefits of available pump types and seem to avoid their complications. However, a profound assessment and their development requires the knowledge of the flow characteristics. This study aimed at their investigation. A functional model was manufactured and investigated with particle image velocimetry. Furthermore, a fluid-structure interaction computational simulation was established to extend the laboratory capabilities. The numerical results precisely converged with the laboratory measurements. Thus, the in silico model enabled the investigation of relevant areas like gap flows that were hardly feasible with laboratory means. Moreover, an economic method for the investigation of design variations was established.

NASA balloon design and flight - Philosophy and criteria

Science.gov (United States)

Smith, I. S., Jr.

1993-01-01

The NASA philosophy and criteria for the design and flight of scientific balloons are set forth and discussed. The thickness of balloon films is standardized at 20.3 microns to isolate potential film problems, and design equations are given for specific balloon parameters. Expressions are given for: flight-stress index, total required thickness, cap length, load-tape rating, and venting-duct area. The balloon design criteria were used in the design of scientific balloons under NASA auspices since 1986, and the resulting designs are shown to be 95 percent effective. These results represent a significant increase in the effectiveness of the balloons and therefore indicate that the design criteria are valuable. The criteria are applicable to four balloon volume classes in combination with seven payload ranges.

Long-Term Risk for Aortic Complications After Aortic Valve Replacement in Patients With Bicuspid Aortic Valve Versus Marfan Syndrome.

Science.gov (United States)

Itagaki, Shinobu; Chikwe, Joanna P; Chiang, Yuting P; Egorova, Natalia N; Adams, David H

2015-06-09

Bicuspid aortic valves are associated with valve dysfunction, ascending aortic aneurysm and dissection. Management of the ascending aorta at the time of aortic valve replacement (AVR) in these patients is controversial and has been extrapolated from experience with Marfan syndrome, despite the absence of comparative long-term outcome data. This study sought to assess whether the natural history of thoracic aortopathy after AVR in patients with bicuspid aortic valve disease is substantially different from that seen in patients with Marfan syndrome. In this retrospective comparison, outcomes of 13,205 adults (2,079 with bicuspid aortic valves, 73 with Marfan syndrome, and 11,053 control patients with acquired aortic valve disease) who underwent primary AVR without replacement of the ascending aorta in New York State between 1995 and 2010 were compared. The median follow-up time was 6.6 years. The long-term incidence of thoracic aortic dissection was significantly higher in patients with Marfan syndrome (5.5 ± 2.7%) compared with those with bicuspid valves (0.55 ± 0.21%) and control group patients (0.41 ± 0.08%, p Marfan syndrome (10.8 ± 4.4%) compared with those with bicuspid valves (4.8 ± 0.8%) and control group patients (1.4 ± 0.2%) (p Marfan syndrome were significantly more likely to undergo thoracic aortic surgery in late follow-up (10.4 ± 4.3%) compared with those with bicuspid valves (2.5 ± 0.6%) and control group patients (0.50 ± 0.09%) (p Marfan syndrome compared with those with bicuspid aortic valves confirm that operative management of patients with bicuspid aortic valves should not be extrapolated from Marfan syndrome and support discrete treatment algorithms for these different clinical entities. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Percutaneous treatment of extrahepatic bile duct stones assisted by balloon sphincteroplasty and occlusion balloon

Energy Technology Data Exchange (ETDEWEB)

Park, Yong Sung; Kim, Ji Hyung; Choi, Young Woo; Lee, Tae Hee; Hwang, Cheol Mog; Cho, Young Jun; Kim, Keum Won [Konyang University Hospital, Daejeon (Korea, Republic of)

2005-12-15

To describe the technical feasibility and usefulness of extrahepatic biliary stone removal by balloon sphincteroplasty and occlusion balloon pushing. Fifteen patients with extrahepatic bile duct stones were included in this study. Endoscopic stone removal was not successful in 13 patients, and two patients refused the procedure due to endoscopy phobia. At first, all patients underwent percutaneous transhepatic biliary drainage (PTBD). A few days later, through the PTBD route, balloon assisted dilatation for common bile duct (CBD) sphincter was performed, and then the stones were pushed into the duodenum using an 11.5 mm occlusion balloon. Success rate, reason for failure, and complications associated with the procedure were evaluated. Eight patients had one stone, five patients had two stones, and two patients had more than five stones. The procedure was successful in 13 patients (13/15). In 12 of the patients, all stones were removed in the first trial. In one patients, residual stones were discovered on follow-up cholangiography, and were subsequently removed in the second trial. Technical failure occurred in two patients. Both of these patients had severely dilated CBD and multiple stones with various sizes. Ten patients complained of pain in the right upper quadrant and epigastrium of the abdomen immediately following the procedure, but there were no significant procedure-related complications such as bleeding or pancreatitis. Percutaneous extrahepatic biliary stone removal by balloon sphincteroplasty and subsequent stone pushing with occlusion balloon is an effective, safe, and technically feasible procedure which can be used as an alternative method in patients when endoscopic extrahepatic biliary stone removal was not successful.

Percutaneous treatment of extrahepatic bile duct stones assisted by balloon sphincteroplasty and occlusion balloon

International Nuclear Information System (INIS)

Park, Yong Sung; Kim, Ji Hyung; Choi, Young Woo; Lee, Tae Hee; Hwang, Cheol Mog; Cho, Young Jun; Kim, Keum Won

2005-01-01

To describe the technical feasibility and usefulness of extrahepatic biliary stone removal by balloon sphincteroplasty and occlusion balloon pushing. Fifteen patients with extrahepatic bile duct stones were included in this study. Endoscopic stone removal was not successful in 13 patients, and two patients refused the procedure due to endoscopy phobia. At first, all patients underwent percutaneous transhepatic biliary drainage (PTBD). A few days later, through the PTBD route, balloon assisted dilatation for common bile duct (CBD) sphincter was performed, and then the stones were pushed into the duodenum using an 11.5 mm occlusion balloon. Success rate, reason for failure, and complications associated with the procedure were evaluated. Eight patients had one stone, five patients had two stones, and two patients had more than five stones. The procedure was successful in 13 patients (13/15). In 12 of the patients, all stones were removed in the first trial. In one patients, residual stones were discovered on follow-up cholangiography, and were subsequently removed in the second trial. Technical failure occurred in two patients. Both of these patients had severely dilated CBD and multiple stones with various sizes. Ten patients complained of pain in the right upper quadrant and epigastrium of the abdomen immediately following the procedure, but there were no significant procedure-related complications such as bleeding or pancreatitis. Percutaneous extrahepatic biliary stone removal by balloon sphincteroplasty and subsequent stone pushing with occlusion balloon is an effective, safe, and technically feasible procedure which can be used as an alternative method in patients when endoscopic extrahepatic biliary stone removal was not successful

Gondola development for CNES stratospheric balloons

Science.gov (United States)

Vargas, A.; Audoubert, J.; Cau, M.; Evrard, J.; Verdier, N.

The CNES has been supporting scientific ballooning since its establishment in 1962. The two main parts of the balloon system or aerostat are the balloon itself and the flight train, comprising the house-keeping gondola, for the control of balloon flight (localization and operational telemetry & telecommand - TM/TC), and the scientific gondola with its dedicated telecommunication system. For zero pressure balloon, the development of new TM/TC system for the housekeeping and science data transmission are going on from 1999. The main concepts are : - for balloon house-keeping and low rate scientific telemetry, the ELITE system, which is based on single I2C bus standardizing communication between the different components of the system : trajectography, balloon control, power supply, scientific TM/TC, .... In this concept, Radio Frequency links are developed between the house keeping gondola and the components of the aerostat (balloon valve, ballast machine, balloon gas temperature measurements, ...). The main objectives are to simplify the flight train preparation in term of gondola testing before flight, and also by reducing the number of long electrical cables integrated in the balloon and the flight train; - for high rate scientific telemetry, the use of functional interconnection Internet Protocol (IP) in interface with the Radio Frequency link. The main idea is to use off-the-shelf IP hardware products (routers, industrial PC, ...) and IP software (Telnet, FTP, Web-HTTP, ...) to reduce the development costs; - for safety increase, the adding, in the flight train, of a totally independent house keeping gondola based on the satellite Inmarsat M and Iridium telecommunication systems, which permits to get real time communications between the on-board data mobile and the ground station, reduced to a PC computer with modem connected to the phone network. These GEO and LEO telecommunication systems give also the capability to operate balloon flights over longer distance

Longitudinal Hemodynamics of Transcatheter and Surgical Aortic Valves in the PARTNER Trial.

Science.gov (United States)

Douglas, Pamela S; Leon, Martin B; Mack, Michael J; Svensson, Lars G; Webb, John G; Hahn, Rebecca T; Pibarot, Philippe; Weissman, Neil J; Miller, D Craig; Kapadia, Samir; Herrmann, Howard C; Kodali, Susheel K; Makkar, Raj R; Thourani, Vinod H; Lerakis, Stamatios; Lowry, Ashley M; Rajeswaran, Jeevanantham; Finn, Matthew T; Alu, Maria C; Smith, Craig R; Blackstone, Eugene H

2017-11-01

Use of transcatheter aortic valve replacement (TAVR) for severe aortic stenosis is growing rapidly. However, to our knowledge, the durability of these prostheses is incompletely defined. To determine the midterm hemodynamic performance of balloon-expandable transcatheter heart valves. In this study, we analyzed core laboratory-generated data from echocardiograms of all patients enrolled in the Placement of Aortic Transcatheter Valves (PARTNER) 1 Trial with successful TAVR or surgical AVR (SAVR) obtained preimplantation and at 7 days, 1 and 6 months, and 1, 2, 3, 4, and 5 years postimplantation. Patients from continued access observational studies were included for comparison. Successful implantation after randomization to TAVR vs SAVR (PARTNER 1A; TAVR, n = 321; SAVR, n = 313), TAVR vs medical treatment (PARTNER 1B; TAVR, n = 165), and continued access (TAVR, n = 1996). Five-year echocardiogram data were available for 424 patients after TAVR and 49 after SAVR. Death or reintervention for aortic valve structural indications, measured using aortic valve mean gradient, effective orifice area, Doppler velocity index, and evidence of hemodynamic deterioration by reintervention, adverse hemodynamics, or transvalvular regurgitation. Of 2795 included patients, the mean (SD) age was 84.5 (7.1) years, and 1313 (47.0%) were female. Population hemodynamic trends derived from nonlinear mixed-effects models showed small early favorable changes in the first few months post-TAVR, with a decrease of -2.9 mm Hg in aortic valve mean gradient, an increase of 0.028 in Doppler velocity index, and an increase of 0.09 cm2 in effective orifice area. There was relative stability at a median follow-up of 3.1 (maximum, 5) years. Moderate/severe transvalvular regurgitation was noted in 89 patients (3.7%) after TAVR and increased over time. Patients with SAVR showed no significant changes. In TAVR, death/reintervention was associated with lower ejection fraction, stroke volume

Simultaneous stent expansion/balloon deflation technique to salvage failed balloon remodeling.

Science.gov (United States)

Ladner, Travis R; He, Lucy; Davis, Brandon J; Froehler, Michael T; Mocco, J

2016-04-01

Herniation, with possible embolization, of coils into the parent vessel following aneurysm coiling remains a frequent challenge. For this reason, balloon or stent assisted embolization remains an important technique. Despite the use of balloon remodeling, there are occasions where, on deflation of the balloon, some coils, or even the entire coil mass, may migrate. We report the successful use of a simultaneous adjacent stent deployment bailout technique in order to salvage coil prolapse during balloon remodeling in three patients. Case No 1 was a wide neck left internal carotid artery bifurcation aneurysm, measuring 9 mm×7.9 mm×6 mm with a 5 mm neck. Case No 2 was a complex left superior hypophyseal artery aneurysm, measuring 5.3 mm×4 mm×5 mm with a 2.9 mm neck. Case No 3 was a ruptured right posterior communicating artery aneurysm, measuring 4 mm×4 mm×4.5 mm with a 4 mm neck. This technique successfully returned the prolapsed coil mass into the aneurysm sac in all cases without procedural complications. The closed cell design of the Enterprise VRD (Codman and Shurtleff Inc, Raynham, Massachusetts, USA) makes it ideal for this bailout technique, by allowing the use of an 0.021 inch delivery catheter (necessary for simultaneous access) and by avoiding the possibility of an open cell strut getting caught on the deflated balloon. We hope this technique will prove useful to readers who may find themselves in a similar predicament. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Are drug-coated balloons cost effective for femoropopliteal occlusive disease? A comparison of bare metal stents and uncoated balloons.

Science.gov (United States)

Poder, Thomas G; Fisette, Jean-François

2016-07-01

To perform a cost-effectiveness analysis to help hospital decision-makers with regard to the use of drug-coated balloons compared with bare metal stents and uncoated balloons for femoropopliteal occlusive disease. Clinical outcomes were extracted from the results of meta-analyses already published, and cost units are those used in the Quebec healthcare network. The literature review was limited to the last four years to obtain the most recent data. The cost-effectiveness analysis was based on a 2-year perspective, and risk factors of reintervention were considered. The cost-effectiveness analysis indicated that drug-coated balloons were generally more efficient than bare metal stents, particularly for patients with higher risk of reintervention (up to CAD$1686 per patient TASC II C or D). Compared with uncoated balloons, results indicated that drug-coated balloons were more efficient if the reintervention rate associated with uncoated balloons is very high and for patients with higher risk of reintervention (up to CAD$3301 per patient). The higher a patient's risk of reintervention, the higher the savings associated with the use of a drug-coated balloon will be. For patients at lower risk, the uncoated balloon strategy is still recommended as a first choice for endovascular intervention.

Anderson localization and ballooning eigenfunctions

International Nuclear Information System (INIS)

Dewar, R.L.; Cuthbert, P.

1999-01-01

In solving the ballooning eigenvalue for a low-aspect-ratio stellarator equilibrium it is found that the quasiperiodic behaviour of the equilibrium quantities along a typical magnetic field line can lead to localization of the ballooning eigenfunction (Anderson localization) even in the limit of zero shear. This localization leads to strong field-line dependence of the ballooning eigenvalue, with different branches attaining their maximum growth rates on different field lines. A method is presented of estimating the field-line dependence of various eigenvalue branches by using toroidal and poloidal symmetry operations on the shear-free ballooning equation to generate an approximate set of eigenfunctions. These zero-shear predictions are compared with accurate numerical solutions for the H-1 Heliac and are shown to give a qualitatively correct picture, but finite shear corrections will be needed to give quantitative predictions

Contemporary results of aortic valve repair for congenital disease: lessons for management and staged strategy.

Science.gov (United States)

Vergnat, Mathieu; Asfour, Boulos; Arenz, Claudia; Suchowerskyj, Philipp; Bierbach, Benjamin; Schindler, Ehrenfried; Schneider, Martin; Hraska, Victor

2017-09-01

Any aortic valve (AoV) operation in children (repair, Ross or mechanical replacement) is a palliation and reinterventions are frequent. AoV repair is a temporary solution primarily aimed at allowing the patient to grow to an age when more definitive solutions are available. We retrospectively analysed AoV repair effectiveness across the whole age spectrum of children, excluding neonates and AoV disease secondary to congenital heart disease. From 2003 to 2015, 193 consecutive patients were included. The mean age was 9.2 ± 6.9 years (22% disease. The procedures performed were commissurotomy shaving (n = 74; 38%), leaflet replacement (n = 78; 40%), leaflet extension (n = 21; 11%) and neocommissure creation (n = 21; 11%). Post-repair geometry was tricuspid in 137 (71%) patients. The 10-year survival rate was 97.1%. Freedom from reoperation and replacement at 7 years was, respectively, 57% (95% confidence interval, 47-66) and 68% (95% confidence interval, 59-76). In multivariate analysis, balloon dilatation before 6 months, the absence of a developed commissure, a non-tricuspid post-repair geometry and cross-clamp duration were predictors for reoperation and replacement. After a mean follow-up period of 5.1 ± 3.0 years, 145 (75%) patients had a preserved native valve, with undisturbed valve function (peak gradient <40 mmHg, regurgitation ≤mild) in 113 (58%). Aortic valve repair in children is safe and effective in delaying the timing for more definitive solution. Surgical strategy should be individualized according to the age of the patient. Avoidance of early balloon dilatation and aiming for a tricuspid post-repair arrangement may improve outcomes. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Application of Electrocautery Needle Knife Combined with Balloon Dilatation versus Balloon Dilatation in the Treatment of Tracheal Fibrotic Scar Stenosis.

Science.gov (United States)

Bo, Liyan; Li, Congcong; Chen, Min; Mu, Deguang; Jin, Faguang

Electrocautery needle knives can largely reduce scar and granulation tissue hyperplasia and play an important role in treating patients with benign stricture. The aim of this retrospective study was to evaluate the efficacy and safety of electrocautery needle knife combined with balloon dilatation versus balloon dilatation alone in the treatment of tracheal stenosis caused by tracheal intubation or tracheotomy. We retrospectively analysed the clinical data of 43 patients with tracheal stenosis caused by tracheotomy or tracheal intubation in our department from January 2013 to January 2016. Among these 43 patients, 23 had simple web-like stenosis and 20 had complex steno sis. All patients were treated under general anaesthesia, and the treatment methods were (1) balloon dilatation alone, (2) needle knife excision of fibrotic tissue combined with balloon dilatation, and (3) needle knife radial incision of fibrotic tissue combined with balloon dilatation. After treatment the symptoms, such as shortness of breath, were markedly improved immediately in all cases. The stenosis degree of patients who were treated with the elec-trocautery needle knife combined with balloon dilatation had better improvement compared with that of those treated with balloon dilatation treatment alone after 3 months (0.45 ± 0.04 vs. 0.67 ± 0.05, p knife combined with balloon dilatation is an effective and safe treatment for tracheal fibrotic stenosis compared with balloon dilatation alone. © 2017 S. Karger AG, Basel.

Recent activities on the scientific ballooning in Japan

International Nuclear Information System (INIS)

Nisimura, J.; Hirosawa, H.

1984-01-01

Scientific ballooning is Japan has been organized by the Institute of Space and Astronautical Science, and about 15 balloons have been launched each year from Sanriku Balloon Center that belongs to this Institute. The balloon center is located in the northern part of Japan. The observations cover the field of X-ray, gamma-ray, infrared astronomy, cosmic rays, and atmospheric science. Systems of lon duration flights such as 'Boomerang Balloons', and fine attitude control systems were developed and widely applied to the scientific observations. International collaborative works were performed in Australia and Indonesia last year. Some details of these activities are reported and possible future collaborations with Braziian balloon group are also discussed. (Author) [pt

The French balloon and sounding rocket space program

Science.gov (United States)

Coutin/Faye, S.; Sadourny, I.

1987-08-01

Stratospheric and long duration flight balloon programs are outlined. Open stratospheric balloons up to 1 million cu m volume are used to carry astronomy, solar system, aeronomy, stratosphere, biology, space physics, and geophysics experiments. The long duration balloons can carry 50 kg payloads at 20 to 30 km altitude for 10 days to several weeks. Pressurized stratospheric balloons, and infrared hot air balloons are used. They are used to study the dynamics of stratospheric waves and atmospheric water vapor. Laboratories participating in sounding rocket programs are listed.

TMBM: Tethered Micro-Balloons on Mars

Science.gov (United States)

Sims, M. H.; Greeley, R.; Cutts, J. A.; Yavrouian, A. H.; Murbach, M.

2000-01-01

The use of balloons/aerobots on Mars has been under consideration for many years. Concepts include deployment during entry into the atmosphere from a carrier spacecraft, deployment from a lander, use of super-pressurized systems for long duration flights, 'hot-air' systems, etc. Principal advantages include the ability to obtain high-resolution data of the surface because balloons provide a low-altitude platform which moves relatively slowly. Work conducted within the last few years has removed many of the technical difficulties encountered in deployment and operation of balloons/aerobots on Mars. The concept proposed here (a tethered balloon released from a lander) uses a relatively simple approach which would enable aspects of Martian balloons to be tested while providing useful and potentially unique science results. Tethered Micro-Balloons on Mars (TMBM) would be carried to Mars on board a future lander as a stand-alone experiment having a total mass of one to two kilograms. It would consist of a helium balloon of up to 50 cubic meters that is inflated after landing and initially tethered to the lander. Its primary instrumentation would be a camera that would be carried to an altitude of up to tens of meters above the surface. Imaging data would be transmitted to the lander for inclusion in the mission data stream. The tether would be released in stages allowing different resolutions and coverage. In addition during this staged release a lander camera system may observe the motion of the balloon at various heights above he lander. Under some scenarios upon completion of the primary phase of TMBM operations, the tether would be cut, allowing TMBM to drift away from the landing site, during which images would be taken along the ground.

Aortic regurgitation after valve-sparing aortic root replacement: modes of failure.

Science.gov (United States)

Oka, Takanori; Okita, Yutaka; Matsumori, Masamichi; Okada, Kenji; Minami, Hitoshi; Munakata, Hiroshi; Inoue, Takeshi; Tanaka, Akiko; Sakamoto, Toshihito; Omura, Atsushi; Nomura, Takuo

2011-11-01

Despite the positive clinical results of valve-sparing aortic root replacement, little is known about the causes of reoperations and the modes of failure. From October 1999 to June 2010, 101 patients underwent valve-sparing aortic root replacement using the David reimplantation technique. The definition of aortic root repair failure included the following: (1) intraoperative conversion to the Bentall procedure; (2) reoperation performed because of aortic regurgitation; and (3) aortic regurgitation equal to or greater than a moderate degree at the follow-up. Sixteen patients were considered to have repair failure. Three patients required intraoperative conversion to valve replacement, 3 required reoperation within 3 months, and another 8 required reoperation during postoperative follow-up. At initial surgery 5 patients had moderate to severe aortic regurgitation, 6 patients had acute aortic dissections, 3 had Marfan syndrome, 2 had status post Ross operations, 3 had bicuspid aortic valves, and 1 had aortitis. Five patients had undergone cusp repair, including Arantius plication in 3 and plication at the commissure in 2. The causes of early failure in 6 patients included cusp perforation (3), cusp prolapse (3), and severe hemolysis (1). The causes of late failure in 10 patients included cusp prolapse (4), commissure dehiscence (3), torn cusp (2), and cusp retraction (1). Patients had valve replacements at a mean of 23 ± 20.9 months after reimplantation and survived. Causes of early failure after valve-sparing root replacement included technical failure, cusp lesions, and steep learning curve. Late failure was caused by aortic root wall degeneration due to gelatin-resorcin-formalin glue, cusp degeneration, or progression of cusp prolapse. Copyright © 2011 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Overview of the NASA balloon R&D program

Science.gov (United States)

Smith, I. Steve, Jr.

1994-01-01

The catastrophic balloon failure during the first half of the 1980's identified the need for a comprehensive and continuing balloon research and development (R&D) commitment by NASA. Technical understanding was lacking in many of the disciplines and processes associated with scientific ballooning. A comprehensive balloon R&D plan was developed in 1986 and implemented in 1987. The objectives were to develop the understanding of balloon system performance, limitations, and failure mechanisms. The program consisted of five major technical areas: structures, performance and analysis, materials, chemistry and processing, and quality control. Research activitites have been conducted at NASA/Goddard Space Flight Center (GSFC)-Wallops Flight Facility (WFF), other NASA centers and government facilities, universities, and the balloon manufacturers. Several new and increased capabilities and resources have resulted from this activity. The findings, capabilities, and plan of the balloon R&D program are presented.

Balloon pulmonary valvotomy – Not just a simple balloon dilatation

Directory of Open Access Journals (Sweden)

Subhendu Mohanty

2014-07-01

Full Text Available Balloon pulmonary valvotomy is the preferred mode of treatment in patients with isolated pulmonary valvar stenosis and has shown good long term results. It is generally considered a safe procedure with few complications. There have been however, case reports of potentially fatal acute severe pulmonary edema occurring after the procedure in some patients. The cause of this complication and its pathophysiology is still not clear. Its occurrence is also infrequent with less than 5 cases reported till now. We report a case of pulmonary valvar stenosis which developed acute severe refractory pulmonary edema immediately after balloon pulmonary valvotomy.

Aortic intramural hematoma : assessment of clinical and radiological features in comparison to acute aortic dissection

International Nuclear Information System (INIS)

Yoon, Kwon Ha; Hwang, Jae Cheol; Lee, Jin Seong; Kang, Duk Hyun; Song, Jae Kwan; Song, Koun Sik; Lim, Tae Hwan

1996-01-01

To compare the clinical and radiological features of aortic intramural hematoma(IMH) to those of acute aortic dissection(AD). We analyzed the clinical and radiological features of 12 patients with aortic IMH and 43 patients with acute AD. In aortic IMH, the diagnoses were made by means of both CT and transesophageal echocardiography(TEE) and included two surgically proven cases. In acute AD, the diagnoses were made by means of CT and TEE and included 21 surgically proven cases. We compared patients ages, etiologies, the extent of the disease, the presence or absence of aortic branch involvement, complications, and outcomes. Aortic IMH tended to develop in older patients (67.8±7.9 vs. 50.4±13.4, P .05). In aortic IMH, there was no involvement of aortic branches, whereas in acute AD, 14(33%) patients showed involvement of one or more aortic branches. Complications of aortic IMH included pericardial effusion (n=2) and pleural effusion (n=4);in acute AD, pericardial effusion (n=7), pleural effusion (n=4), aortic insufficiency (n=8), cerebral infarction (n=3), renal infarction (n=4) and spinal infarction (n=1) were seen. There was one (8%) death due to aortic IMH and ten (23%) deaths due to acute AD (p<.01). Aortic IMH is characterized by its occurrence in older patients with hypertension, a less frequent incidence of complications, and a more favorable outcome than acute AD

Transcatheter aortic valve replacement

Science.gov (United States)

... gov/ency/article/007684.htm Transcatheter aortic valve replacement To use the sharing features on this page, please enable JavaScript. Transcatheter aortic valve replacement (TAVR) is surgery to replace the aortic valve. ...

Left Ventricular Assist Device Implantation with Concomitant Aortic Valve and Ascending Aortic Replacement.

Science.gov (United States)

Huenges, Katharina; Panholzer, Bernd; Cremer, Jochen; Haneya, Assad

2018-01-01

Left ventricular assist device (LVAD) is nowadays a routine therapy for patients with advanced heart failure. We present the case of a 74-year-old male patient who was admitted to our center with terminal heart failure in dilated cardiomyopathy and ascending aortic aneurysm with aortic valve regurgitation. The LVAD implantation with simultaneous aortic valve and supracoronary ascending aortic replacement was successfully performed.

Early and mid-term results with the Growth Stent--a possible concept for transcatheter treatment of aortic coarctation from infancy to adulthood by stent implantation?

Science.gov (United States)

Ewert, Peter; Peters, Bjoern; Nagdyman, Nicole; Miera, Oliver; Kühne, Titus; Berger, Felix

2008-01-01

Evaluation of the Growth Stent-a stent consisting of two stent halves connected by reabsorbable sutures-for the treatment of aortic coarctation in infants. Surveillance study of 13 Growth Stents implanted in 12 patients aged 1-15 months (median 5 months). Body weight ranged from 3.4-12.8 kg (median 5.4 kg). Eight patients suffered from aortic (re-)coarctation, four of them from stenosis of the aortic anastomosis after a Norwood I procedure. The follow-up period was 24 months (11-51 months). Pressure gradients immediately after stent implantation decreased from 30 mm Hg (range 20-50 mm Hg) to 8 mm Hg (range 0-15 mm Hg). Five patients had one (3 pts) or two (2 pts) balloon dilations 3-28 months (median 12 months) after Growth Stent implantation. The median pressure gradient decreased from 25 mm Hg (range 15-30 mm Hg) to 15 mm Hg (range 5-25 mm Hg). Six patients received a large stent after 19-34 months. Median body weight was 11.8 kg (9.4-15 kg). The Growth Stent is suitable for the acute treatment of aortic coarctation in infants and can be overstented later on--if necessary--with a larger stent without causing restriction. Copyright 2008 Wiley-Liss, Inc.

Particle Astrophysics in NASA's Long Duration Balloon Program

International Nuclear Information System (INIS)

Gorham, Peter W.

2013-01-01

A century after Viktor Hess' discovery of cosmic rays, balloon flights still play a central role in the investigation of cosmic rays over nearly their entire spectrum. We report on the current status of NASA balloon program for particle astrophysics, with particular emphasis on the very successful Antarctic long-duration balloon program, and new developments in the progress toward ultra-long duration balloons

Infected aortic aneurysm and inflammatory aortic aneurysm. In search of an optimal differential diagnosis

International Nuclear Information System (INIS)

Ishizaka, Nobukazu; Sohmiya, Koichi; Miyamura, Masatoshi; Umeda, Tatsuya; Tsuji, Motomu; Katsumata, Takahiro; Miyata, Tetsuro

2012-01-01

Infected aortic aneurysm and inflammatory aortic aneurysm each account for a minor fraction of the total incidence of aortic aneurysm and are associated with periaortic inflammation. Despite the similarity, infected aortic aneurysm generally shows a more rapid change in clinical condition, leading to a fatal outcome; in addition, delayed diagnosis and misuse of corticosteroid or immunosuppressing drugs may lead to uncontrolled growth of microorganisms. Therefore, it is mandatory that detection of aortic aneurysm is followed by accurate differential diagnosis. In general, infected aortic aneurysm appears usually as a saccular form aneurysm with nodularity, irregular configuration; however, the differential diagnosis may not be easy sometimes for the following reasons: symptoms, such as abdominal and/or back pain and fever, and blood test abnormalities, such as elevated C-reactive protein and enhanced erythrocyte sedimentation rate, are common in infected aortic aneurysm, but they are not found infrequently in inflammatory aortic aneurysm; some inflammatory aortic aneurysms are immunoglobulin (Ig) G4-related, but not all of them; the prevalence of IgG4 positivity in infected aortic aneurysm has not been well investigated; enhanced uptake of 18F-fluorodeoxyglucose (FDG) by 18F-FDG-positron emission tomography may not distinguish between inflammation mediated by autoimmunity and that mediated by microorganism infection. Here we discuss the characteristics of these two forms of aortic aneurysm and the points of which we have to be aware before reaching a final diagnosis. (author)

Laser welding of balloon catheters

Science.gov (United States)

Flanagan, Aidan J.

2003-03-01

The balloon catheter is one of the principal instruments of non-invasive vascular surgery. It is used most commonly for angioplasty (and in recent years for delivering stents) at a multitude of different sites in the body from small arteries in the heart to the bilary duct. It is composed of a polymer balloon that is attached to a polymer shaft at two points called the distal and proximal bonds. The diverse utility of balloon catheters means a large range of component sizes and materials are used during production; this leads to a complexity of bonding methods and technology. The proximal and distal bonds have been conventionally made using cyanoacrylate or UV curing glue, however with performance requirements of bond strength, flexibility, profile, and manufacturing costs these bonds are increasingly being made by welding using laser, RF, and Hot Jaw methods. This paper describes laser welding of distal and proximal balloon bonds and details beam delivery, bonding mechanisms, bond shaping, laser types, and wavelength choice.

NASA Langley Research Center tethered balloon systems

Science.gov (United States)

Owens, Thomas L.; Storey, Richard W.; Youngbluth, Otto

1987-01-01

The NASA Langley Research Center tethered balloon system operations are covered in this report for the period of 1979 through 1983. Meteorological data, ozone concentrations, and other data were obtained from in situ measurements. The large tethered balloon had a lifting capability of 30 kilograms to 2500 meters. The report includes descriptions of the various components of the balloon systems such as the balloons, the sensors, the electronics, and the hardware. Several photographs of the system are included as well as a list of projects including the types of data gathered.

Minocycline Effectively Protects the Rabbit's Spinal Cord From Aortic Occlusion-Related Ischemia.

Science.gov (United States)

Drenger, Benjamin; Fellig, Yakov; Ben-David, Dror; Mintz, Bella; Idrees, Suhel; Or, Omer; Kaplan, Leon; Ginosar, Yehuda; Barzilay, Yair

2016-04-01

To identify the minocycline anti-inflammatory and antiapoptotic mechanisms through which it is believed to exert spinal cord protection during aortic occlusion in the rabbit model. An animal model of aortic occlusion-related spinal cord ischemia. Randomized study with a control group and pre-ischemia and post-ischemia escalating doses of minocycline to high-dose minocycline in the presence of either hyperglycemia, a pro-apoptotic maneuver, or wortmannin, a specific phosphatidylinositol 3-kinase antagonist. Tertiary medical center and school of medicine laboratory. Laboratory animals-rabbits. Balloon obstruction of infrarenal aorta introduced via femoral artery incision. Severe hindlimb paralysis (mean Tarlov score 0.36±0.81 out of 3) was observed in all the control group animals (9 of 11 with paraplegia and 2 of 11 with paraparesis) compared with 11 of 12 neurologically intact animals (mean Tarlov score 2.58±0.90 [p = 0.001 compared with control]) in the high-dose minocycline group. This protective effect was observed partially during a state of hyperglycemia and was completely abrogated by wortmannin. Minocycline administration resulted in higher neurologic scores (p = 0.003) and a shift to viable neurons and more apoptotic-stained nuclei resulting from reduced necrosis (p = 0.001). In a rabbit model of infrarenal aortic occlusion, minocycline effectively reduced paraplegia by increasing the number of viable neurons in a dose-dependent manner. Its action was completely abrogated by inhibiting the phosphatidylinositol 3-kinase pathway and was inhibited partially by the pro-apoptotic hyperglycemia maneuver, indicating that the activation of cell salvage pathways and mitochondrial sites are possible targets of minocycline action in an ischemic spinal cord. Copyright © 2016. Published by Elsevier Inc.

Aortic root surgery in Marfan syndrome: Comparison of aortic valve-sparing reimplantation versus composite grafting.

Science.gov (United States)

Karck, Matthias; Kallenbach, Klaus; Hagl, Christian; Rhein, Christine; Leyh, Rainer; Haverich, Axel

2004-02-01

The objective of this study was to compare the results of aortic valve-sparing reimplantation and aortic root replacement with mechanical valve conduits in patients with Marfan syndrome undergoing operation for aortic root aneurysms. Patients and methods Between March 1979 and April 2002, 119 patients with clinical evidence of Marfan syndrome underwent composite graft replacement with mechanical valve conduits (n = 74) or aortic valve-sparing reimplantation according to David (n = 45). The underlying causes were aortic dissection type A (43 patients) and aneurysms (76 patients). Patients undergoing aortic valve reimplantation were younger compared with patients undergoing composite grafting (28 vs 35 years, P =.002) and had longer intraoperative aortic crossclamp times (125 vs 78 minutes, P valve reimplantation (P =.15). Mean follow-up was 30 months for patients undergoing aortic valve reimplantation and 114 months for patients undergoing composite grafting. Freedom from reoperation and death after 5 years postoperatively was 92% and 89% in patients undergoing composite grafting and 84% and 96% in patients undergoing aortic valve reimplantation (P =.31; P =.54), respectively. Thromboembolic complications or late postoperative bleeding occurred in 17 patients undergoing composite grafting, and an early postoperative event occurred in 1 patient undergoing aortic valve reimplantation. The results of aortic valve reimplantation and composite grafting of the aortic valve and ascending aorta with mechanical valve conduits are similar with regard to early and mid-term postoperative mortality and to the incidence of late reoperations in patients with Marfan syndrome. The low risk of thromboembolic or bleeding complications favors aortic valve reimplantation in these patients.

Endoluminal Treatment of Ruptured Abdominal Aortic Aneurysm with Small Intestinal Submucosa Sandwich Endografts: A Pilot Study in Sheep

International Nuclear Information System (INIS)

Yamada, Katsuyuki; Pavcnik, Dusan; Uchida, Barry T.; Timmermans, Hans A.; Corless, Christopher L.; Yin, Qiang; Yamakado, Koichiro; Wha Park, Joong; Roesch, Josef; Keller, Frederick S.; Sato, Morio; Yamada, Ryusaku

2001-01-01

Purpose: To evaluate efficacy of small intestinal submucosa (SIS) Sandwich endografts for the treatment of acute rupture of abdominal aortic aneurysms (AAA) and to explore the short-term reaction of the aorta to this material.Methods: In eight adult sheep, an infrarenal AAA was created transluminally by dilation of a short Palmaz stent. In six sheep, the aneurysm was then ruptured by overdilation of the stent with a large angioplasty balloon. Two sheep with AAAs that were not ruptured served as controls. A SIS Sandwich endograft, consisting of a Z stent frame with 5 bodies and covered inside and out with SIS, was used to exclude the ruptured and non-ruptured AAAs. Follow-up aortography was done immediately after the procedure and before sacrifice at 4, 8, or 12 weeks. Autopsy and histologic studies followed.Results: Endograft placement was successful in all eight sheep. Both ruptured and non-ruptured AAAs were successfully excluded. Three animals with AAA rupture developed hind leg paralysis due to compromise of the arterial supply to the lower spinal cord and were sacrificed 1 day after the procedure. In five animals, three with rupture and two controls, follow-up aortograms revealed no aortic stenoses and no perigraft leaks. Gross and histologic studies revealed incorporation of the endografts into the aortic wall with replacement of SIS by dense neointima that was completely endothelialized in areas where the endograft was in direct contact with the aortic wall. In central portions of the endograft, in contact with the thrombosed aneurysm, endothelialization was incomplete even at 12 weeks.Conclusion: The SIS Sandwich endografts effectively excluded simple AAAs and ruptured AAAs. They were rapidly incorporated into the aortic wall. A detailed long-term study is warranted

Heat Transfer Model for Hot Air Balloons

Science.gov (United States)

Llado-Gambin, Adriana

A heat transfer model and analysis for hot air balloons is presented in this work, backed with a flow simulation using SolidWorks. The objective is to understand the major heat losses in the balloon and to identify the parameters that affect most its flight performance. Results show that more than 70% of the heat losses are due to the emitted radiation from the balloon envelope and that convection losses represent around 20% of the total. A simulated heating source is also included in the modeling based on typical thermal input from a balloon propane burner. The burner duty cycle to keep a constant altitude can vary from 10% to 28% depending on the atmospheric conditions, and the ambient temperature is the parameter that most affects the total thermal input needed. The simulation and analysis also predict that the gas temperature inside the balloon decreases at a rate of -0.25 K/s when there is no burner activity, and it increases at a rate of +1 K/s when the balloon pilot operates the burner. The results were compared to actual flight data and they show very good agreement indicating that the major physical processes responsible for balloon performance aloft are accurately captured in the simulation.

Transcatheter valve-in-valve implantation due to severe aortic regurgitation in a degenerated aortic homograft

DEFF Research Database (Denmark)

Olsen, Lene Kjaer; Engstrøm, Thomas; Søndergaard, Lars

2009-01-01

Transcatheter aortic valve implantation (TAVI) in severe aortic stenosis has proven to be a feasible and effective treatment modality for inoperable patients. Until now, neither aortic regurgitation nor degenerated bioprostheses has been an indication for TAVI. However, this article reports...... a successful valve-in-valve implantation of a CoreValve aortic valve prosthesis through the right subclavian artery in a case of severe aortic regurgitation within a degenerated aortic homograft. The case exemplifies the possibilities of expanding the indications for TAVI, as well as other vascular access...

Deployment Instabilities of Lobed-Pumpkin Balloon

Science.gov (United States)

Nakashino, Kyoichi

A lobed-pumpkin balloon, currently being developed in ISAS/JAXA as well as in NASA, is a promising vehicle for long duration scientific observations in the stratosphere. Recent ground and flight experiments, however, have revealed that the balloon has deployment instabilities under certain conditions. In order to overcome the instability problems, a next generation SPB called 'tawara' type balloon has been proposed, in which an additional cylindrical part is appended to the standard lobed-pumpkin balloon. The present study investigates the deployment stability of tawara type SPB in comparison to that of standard lobed-pumpkin SPB through eigenvalue analysis on the basis of finite element methods. Our numerical results show that tawara type SPB enjoys excellent deployment performance over the standard lobed-pumpkin SPBs.

Gigantic balloon type artificial lightning generator

Energy Technology Data Exchange (ETDEWEB)

Horii; kenji

1988-09-05

This paper outlines a hot-air balloon type Van de Graaf 50-MV generator which can generate a 50,000,000 V, 0.2 to 0.3 coulomb artificial lightning comparable to natural lightning discharge and reports the results of investigation on discharging experiments conducted using this apparatus. The subjects covered are as follows: (1) Outline of the hot-air balloon type Van de Graaf 50-MV generator, (2) electric characteristics of the Van de Graaf 50-MV generator, (3) charge transfer with film and balloon charging, (4) the load of the balloon and buoyancy calculation, (5) leakage of charges, (6) study of charging experiments, and (7) evaluation of the apparatus and its method and problems to be solved. (4 figs, 4 tabs, 4 refs)

Balloon cell nevus of the iris.

Science.gov (United States)

Morcos, Mohib W; Odashiro, Alexandre; Bazin, Richard; Pereira, Patricia Rusa; O'Meara, Aisling; Burnier, Miguel N

2014-12-01

Balloon cell nevus is a rare histopathological lesion characterized by a predominance of large, vesicular and clear cells, called balloon cells. There is only 1 case of balloon cell nevus of the iris reported in the literature. A 55 year-old man presented a pigmented elevated lesion in the right iris since the age of 12 years old. The lesion had been growing for the past 2 years and excision was performed. Histopathological examination showed a balloon cell nevus composed of clear and vacuolated cells without atypia. A typical spindle cell nevus of the iris was also observed. The differential diagnosis included xanthomatous lesions, brown adipocyte or other adipocytic lesions, clear cell hidradenoma, metastatic clear cell carcinoma of the kidney and clear cell sarcoma. The tumor was positive for Melan A, S100 protein and HMB45. Balloon cell nevus of the iris is rare but should be considered in the differential diagnosis of melanocytic lesions of the iris. Copyright © 2014 Elsevier GmbH. All rights reserved.

Aortic valve-sparing operations in aortic root aneurysms: remodeling or reimplantation?

Science.gov (United States)

Rahnavardi, Mohammad; Yan, Tristan D; Bannon, Paul G; Wilson, Michael K

2011-08-01

A best evidence topic was written according to a structured protocol. The question addressed was whether the reimplantation (David) technique or the remodeling (Yacoub) technique provides the optimum event free survival in patients with an aortic root aneurysm suitable for an aortic valve-sparing operation. In total, 392 papers were found using the reported search criteria, of which 14 papers provided the best evidence to answer the clinical question. A total of 1338 patients (Yacoub technique in 606 and David technique in 732) from 13 centres were included. In most series, cardiopulmonary bypass time and aortic cross-clamp time were longer for the David technique compared to the Yacoub technique. Early mortality was comparable between the two techniques (0-6.9% for the Yacoub technique and 0-6% for the David technique). There is a tendency for a higher freedom from significant long-term aortic insufficiency in the David group than the Yacoub group, which does not necessarily result in a higher reoperation rate in the Yacoub group. In the largest series reported, freedom from a moderate-to-severe aortic insufficiency at 12 years was 82.6 ± 6.2% in the Yacoub and 91.0 ± 3.8% in the David group (P=0.035). Freedom from reoperation at the same time point was 90.4 ± 4.7% in the Yacoub group and 97.4 ± 2.2% in the David group (P=0.09). In another series, freedom from reoperation at a follow-up time of about four years was 89 ± 4% in the Yacoub group and 98 ± 2% in the David group. Although some authors merely preferred the Yacoub technique for a bicuspid aortic valve, the accumulated evidence in the current review indicates comparable results for both techniques in a bicuspid aortic valve. Current evidence is in favour of the David rather than the Yacoub technique in pathologies such as Marfan syndrome, acute type A aortic dissection, and excessive annular dilatation that may impair aortic root integrity. Careful selection of patients for each technique and

Incidence and progression of mild aortic regurgitation after Tirone David reimplantation valve-sparing aortic root replacement.

Science.gov (United States)

Stephens, Elizabeth H; Liang, David H; Kvitting, John-Peder Escobar; Kari, Fabian A; Fischbein, Michael P; Mitchell, R Scott; Miller, D Craig

2014-01-01

The study objective was to determine whether recurrent or residual mild aortic regurgitation, which occurs after valve-sparing aortic root replacement, progresses over time. Between 2003 and 2008, 154 patients underwent Tirone David-V valve-sparing aortic root replacement; 96 patients (62%) had both 1-year (median, 12 ± 4 months) and mid-term (62 ± 22 months) transthoracic echocardiograms available for analysis. Age of patients averaged 38 ± 13 years, 71% were male, 31% had a bicuspid aortic valve, 41% had Marfan syndrome, and 51% underwent aortic valve repair, predominantly cusp free margin shortening. Forty-one patients (43%) had mild aortic regurgitation on 1-year echocardiogram. In 85% of patients (n = 35), mild aortic regurgitation remained stable on the most recent echocardiogram (median, 57 ± 20 months); progression to moderate aortic regurgitation occurred in 5 patients (12%) at a median of 28 ± 18 months and remained stable thereafter; severe aortic regurgitation developed in 1 patient, eventually requiring reoperation. Five patients (5%) had moderate aortic regurgitation at 1 year, which did not progress subsequently. Two patients (2%) had more than moderate aortic regurgitation at 1 year, and both ultimately required reoperation. Although mild aortic regurgitation occurs frequently after valve-sparing aortic root replacement, it is unlikely to progress over the next 5 years and should not be interpreted as failure of the valve-preservation concept. Further, we suggest that mild aortic regurgitation should not be considered nonstructural valve dysfunction, as the 2008 valve reporting guidelines would indicate. We need 10- to 15-year follow-up to learn the long-term clinical consequences of mild aortic regurgitation early after valve-sparing aortic root replacement. Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Mars Solar Balloon Lander, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The Mars Solar Balloon Lander (MSBL) is a novel concept which utilizes the capability of solar-heated hot air balloons to perform soft landings of scientific...

Bovine aortic arch: A novel association with thoracic aortic dilation

International Nuclear Information System (INIS)

Malone, C.D.; Urbania, T.H.; Crook, S.E.S.; Hope, M.D.

2012-01-01

Aim: To investigate whether there is a link between bovine arch and thoracic aortic aneurysm. Materials and methods: Computed tomography (CT) and magnetic resonance imaging (MRI) images of the thorax of 191 patients with dilated thoracic aortas and 391 consecutive, unselected patients as controls were retrospectively reviewed. Bovine arch was considered present if either a shared origin of the left common carotid and innominate arteries or an origin of the left common carotid from the innominate artery was identified. A chi-square test was used to evaluate the significance of differences between subgroups. Results: A trend towards increased prevalence of bovine arch was seen in patients with dilated aortas (26.2%) compared to controls (20.5%, p = 0.12). The association was statistically significant in patients over 70 years old (31.9%, p = 0.019) and when dilation involved the aortic arch (47.6%, p = 0.003). Conclusions: An association between bovine arch and aortic dilation is seen in older patients, and when dilation involves the aortic arch. Bovine arch should be considered a potential risk factor for thoracic aortic aneurysm.

Endovascular Repair of Acute Symptomatic Pararenal Aortic Aneurysm With Three Chimney and One Periscope Graft for Complete Visceral Artery Revascularization

International Nuclear Information System (INIS)

Brechtel, Klaus; Ketelsen, Dominik; Endisch, Andrea; Heller, Stephan; Heuschmid, Martin; Stock, Ulrich A.; Kalender, Guenay

2012-01-01

PurposeTo describe a modified endovascular technique for complete revascularization of visceral and renal arteries in symptomatic pararenal aortic aneurysm (PRAA).TechniqueArterial access was surgically established in both common femoral arteries (CFAs) and the left subclavian artery (LSA). Revascularization of the left renal artery, the celiac trunk, and the superior mesenteric artery was performed through one single sheath via the LSA. Suitable covered stents were put in the aortic branches but not deployed. The right renal artery was accessed over the left CFA. Due to the longitudinal extension of the presented aneurysm two stent-grafts were introduced via the right CFA. After deploying the aortic stent-grafts, all covered stents in the side branches were deployed consecutively with a minimum overlap of 5 mm over the cranial and caudal stent-graft edges. Simultaneous ballooning was performed to fully expand all stent-grafts and warranty patency. Conclusion: This is the first report in the literature of chimney grafting in PRAA for complete revascularization of visceral and renal branches by using more than two covered stents introduced from one side through one single sheath. However this technique is modified, it should be used only in bailout situations when branched stent-grafts are not available and/or surgery is not suitable.

Vertical sounding balloons for stratospheric photochemistry

Science.gov (United States)

Pommereau, J. P.

The use of vertical sounding balloons for stratospheric photochemistry studies is illustrated by the use of a vertical piloted gas balloon for the search of NO2 diurnal variations. It is shown that the use of montgolfieres (hot air balloons) can enhance the vertical sounding technique. Particular attention is given to a sun-heated montgolfiere and to the more sophisticated infrared montgolfiere that is able to perform three to four vertical excursions per day and to remain aloft for weeks or months.

Boston's balloon dilatation for treatment of cardiac achalasia

International Nuclear Information System (INIS)

Yin Jianguo; Song Jinwen; Yang Yan; Liu Xiaohong; Fu Zhiming; Zhang Yaqin

2001-01-01

Objective: To review and summarize effectiveness and method of the Boston's balloon dilation in cardiac achalasia. Methods: The intensified guide wire was inserted into stomach through mouth cavity under TV control. The Boston's balloon was inserted to the cardiac stricture through the guide wire and dilatated with 15% contrast medium with to a maximum diameter for five minutes and then the balloon was dilatated again for 3-5 minutes, all together for 3-4 times. The severe stricture must be pre-dilatated with 20-25 mm diameter balloon. Results: The balloon insertion was technically successful in all 26 patients. The once success of balloon dilation was achieved in 24 patients and twice in other 2. Follow-up time was from 2 weeks to 31 months (mean 10.6 months). Recurrent stenosis had not occurred in all patients. Remission rate of dysphagia was 100%. Esophageal reflux occurred in 3 patients. Conclusions: The Boston's balloon dilatation is simple and effective for treatment of cardiac achalasia. The method sometimes may replace surgical procedure

Clinical experience with the Monorail balloon catheter for coronary angioplasty.

Science.gov (United States)

Finci, L; Meier, B; Roy, P; Steffenino, G; Rutishauser, W

1988-01-01

The Monorail balloon catheter is distinctly different from other current balloon catheters: the guidewire passes through the balloon itself, exits the catheter proximal to the balloon, and runs alongside its small shaft (3 French) through the guiding catheter. Monorail coronary angioplasty was attempted in 61 patients on 73 lesions with balloons from 2.0 to 3.7 mm. Angiographic success was obtained in 66 lesions (90%). For 15 lesions, balloon exchanges were needed. In three lesions, the Monorail balloon failed to cross the lesion, while a standard balloon succeeded; two lesions could not be crossed with any balloon. Vessel occlusion occurred in four patients: two had emergency surgery without infarct (one died suddenly 4 days later and one had a stroke 1 day later), one was recanalized with a standard balloon, and one had a myocardial infarct. Continuous infusion of urokinase was used until patient 3 in whom problems with the delivery system led to cardiocerebral air embolization (with complete recovery). No thrombotic complications were observed in the subsequent 58 patients with only a bolus of 10,000 U of heparin. The Monorail balloon facilitates contrast injections and balloon exchanges but appears more difficult to pass through tight lesions. Omission of the previously recommended infusion with a thrombolytic agent proved safe.

Use of monorail PTCA balloon catheter for local drug delivery.

Science.gov (United States)

Trehan, Vijay; Nair, Girish M; Gupta, Mohit D

2007-01-01

We report the use of monorail coronary balloon as an infusion catheter to give bailout abciximab selectively into the site of stent thrombosis as an adjunct to plain old balloon angioplasty (POBA) in a patient of subacute stent thrombosis of the left anterior descending coronary artery. The balloon component (polyamide material) of the monorail balloon catheter was shaved off the catheter so that abciximab injected through the balloon port of the catheter exited out the shaft of the balloon catheter at the site from where the balloon material was shaved off. We believe that selective infusion with abciximab along with POBA established antegrade flow and relieved the patient's ischemia. In the absence of essential hardware to give intracoronary drugs in an emergency situation, one may employ our technique of infusion through a monorail balloon catheter after shaving the balloon component from the catheter.

Reverse extra-anatomic aortic arch debranching procedure allowing thoracic endovascular aortic repair of a chronic ascending aortic aneurysm

Directory of Open Access Journals (Sweden)

Ludovic Canaud, MD, PhD

2018-06-01

Full Text Available A 79-year-old woman was admitted with a large chronic dissecting ascending aortic aneurysm starting 5 mm distal to the ostia of the left coronary artery and ending immediately proximal to the innominate artery. A reverse extra-anatomic aortic arch debranching procedure was performed. During the same operative time, through a transapical approach, a thoracic stent graft was deployed with the proximal landing zone just distal to the coronary ostia and the distal landing zone excluding the origin of the left common carotid artery. The postoperative course was uneventful. Computed tomography at 12 months documented patent extra-anatomic aortic arch debranching and no evidence of endoleak. Keywords: Ascending aorta, Thoracic aorta, Aortic dissection, Stent graft

Retrograde ascending aortic dissection during or after thoracic aortic stent graft placement: insight from the European registry on endovascular aortic repair complications

DEFF Research Database (Denmark)

Eggebrecht, Holger; Thompson, Matt; Rousseau, Hervé

2009-01-01

BACKGROUND: Single-center reports have identified retrograde ascending aortic dissection (rAAD) as a potentially lethal complication of thoracic endovascular aortic repair (TEVAR). METHODS AND RESULTS: Between 1995 and 2008, 28 centers participating in the European Registry on Endovascular Aortic...

A system for visualization and automatic placement of the endoclamp balloon catheter

Science.gov (United States)

Furtado, Hugo; Stüdeli, Thomas; Sette, Mauro; Samset, Eigil; Gersak, Borut

2010-02-01

The European research network "Augmented Reality in Surgery" (ARIS*ER) developed a system that supports minimally invasive cardiac surgery based on augmented reality (AR) technology. The system supports the surgical team during aortic endoclamping where a balloon catheter has to be positioned and kept in place within the aorta. The presented system addresses the two biggest difficulties of the task: lack of visualization and difficulty in maneuvering the catheter. The system was developed using a user centered design methodology with medical doctors, engineers and human factor specialists equally involved in all the development steps. The system was implemented using the AR framework "Studierstube" developed at TU Graz and can be used to visualize in real-time the position of the balloon catheter inside the aorta. The spatial position of the catheter is measured by a magnetic tracking system and superimposed on a 3D model of the patient's thorax. The alignment is made with a rigid registration algorithm. Together with a user defined target, the spatial position data drives an actuator which adjusts the position of the catheter in the initial placement and corrects migrations during the surgery. Two user studies with a silicon phantom show promising results regarding usefulness of the system: the users perform the placement tasks faster and more accurately than with the current restricted visual support. Animal studies also provided a first indication that the system brings additional value in the real clinical setting. This work represents a major step towards safer and simpler minimally invasive cardiac surgery.

Structure variations of pumpkin balloon

Science.gov (United States)

Yajima, N.; Izutsu, N.; Honda, H.

2004-01-01

A lobed pumpkin balloon by 3-D gore design concept is recognized as a basic form for a super-pressure balloon. This paper deals with extensions of this design concept for other large pressurized membrane structures, such as a stratospheric airship and a balloon of which volume is controllable. The structural modifications are performed by means of additional ropes, belts or a strut. When the original pumpkin shape is modified by these systems, the superior characteristics of the 3-D gore design, incorporating large bulges with a small local radius and unidirectional film tension, should be maintained. Improved design methods which are adequate for the above subjects will be discussed in detail. Application for ground structures are also mentioned.

Development of a Super-Pressure Balloon with an Improved Design

Science.gov (United States)

Izutsu, Naoki; Akita, Daisuke; Fuke, Hideyuki; Iijima, Issei; Kato, Yoichi; Kawada, Jiro; Matsushima, Kiyoho; Matsuzaka, Yukihiko; Mizuta, Eiichi; Nakada, Takashi; Nonaka, Naoki; Saito, Yoshitaka; Takada, Atsushi; Tamura, Keisuke; Yamada, Kazuhiko; Yoshida, Tetsuya

A zero-pressure balloon used for scientific observation in the stratosphere has an unmanageable limitation that its floating altitude decreases during a nighttime because of temperature drop of the lifting gas. Since a super-pressure balloon may not change its volume, the lifetime can extend very long. We had introduced so called the ‘lobed-pumpkin’ type of super-pressure balloon that can realize a full-scale long-duration balloon and it will be in practical use in the very near future. As for larger super-pressure balloons, however, we still have some potential difficulties to be resolved. We here propose a new design suitable for a larger super-pressure balloon, which is roughly ‘lobed pumpkin with lobed cylinder’ and can adapt a single design for balloons of a wide range of volumes. Indoor inflation tests were successfully carried out with balloons designed and made by the method. It has been shown that the limit of the resisting pressure differential for a new designed balloon is same as that of a normal lobed-pumpkin balloon.

Ballooning behavior in the golden orbweb spider Nephilapilipes (Araneae: Nephilidae

Directory of Open Access Journals (Sweden)

Vanessa M.J. Lee

2015-01-01

Full Text Available Ballooning, a mode of aerial dispersal in spiders, is an innate behavior that requires appropriate physiological and meteorological conditions. Although only rarely reported in the golden orbweb spiders, family Nephilidae, the large geographic distributions of most nephilids—in particular of Nephila species—would imply that these spiders likely routinely disperse by ballooning in spite of giant female sizes. Here we study ballooning behavior in the golden orbweb spider Nephila pilipes (Fabricius, 1793. Specifically, we test for the propensity of spiderlings to deploy ballooning as a dispersal mechanism. We subjected a total of 59 first-instar spiderlings to a wind experiment at two wind speeds (2.17 ± 0.02 m s-1 and 3.17 ± 0.02 m s-1 under laboratory conditions. Under an average wind speed of 3.17 m s-1, none of the spiderlings exhibited pre-ballooning or ballooning behavior. However, at an average wind speed of 2.17 m s-1, 53 (89.8% spiderlings showed pre-ballooning behavior, and 17 (32.1% of the pre-ballooners ultimately ballooned. Our results concur with prior reports on spiderlings of other families that pre-ballooning behavior is a requirement for ballooning to occur. Furthermore, although we cannot rule out other dispersal mechanisms such as synanthropic spread, our findings suggest that the widespread N. pilipes uses ballooning to colonize remote oceanic islands.

Geometric Deformations of the Thoracic Aorta and Supra-Aortic Arch Branch Vessels Following Thoracic Endovascular Aortic Repair.

Science.gov (United States)

Ullery, Brant W; Suh, Ga-Young; Hirotsu, Kelsey; Zhu, David; Lee, Jason T; Dake, Michael D; Fleischmann, Dominik; Cheng, Christopher P

2018-04-01

To utilize 3-D modeling techniques to better characterize geometric deformations of the supra-aortic arch branch vessels and descending thoracic aorta after thoracic endovascular aortic repair. Eighteen patients underwent endovascular repair of either type B aortic dissection (n = 10) or thoracic aortic aneurysm (n = 8). Computed tomography angiography was obtained pre- and postprocedure, and 3-D geometric models of the aorta and supra-aortic branch vessels were constructed. Branch angle of the supra-aortic branch vessels and curvature metrics of the ascending aorta, aortic arch, and stented thoracic aortic lumen were calculated both at pre- and postintervention. The left common carotid artery branch angle was lower than the left subclavian artery angles preintervention ( P Supra-aortic branch vessel angulation remains relatively static when proximal landing zones are distal to the left common carotid artery.

Aortic obstruction: anatomy and echocardiography

Directory of Open Access Journals (Sweden)

Keirns Candace

2006-09-01

Full Text Available Abstract Echocardiography is a valuable non-invasive technique for identifying the site and type of aortic obstruction. Knowledge of the morphological details of each type of obstruction is the basis for correct interpretation of the diagnostic images and clinical decisions. This study was undertaken to correlate the echocardiographic images with anatomic specimens of equivalent valvular and supravalvular aortic obstruction. Specimens were part of the collection of the Department of Embryology. Fifty six patients were studied, and forty specimens with aortic obstruction were analyzed. Echocardiographic characteristics: Thirty one (55.3% patients were women and twenty five (44.7% men. Valvular aortic obstruction was found in Thirty six patients (64.3 % and supravalvular aortic obstruction in twenty (35.7%. Anatomic characteristics: Of the forty specimens examined, twenty one (52.5% had valvular aortic obstruction and nineteen (47.5% supravalvular aortic obstruction. The anatomoechocardiographic correlation clearly showed that the anatomic findings of the specimen hearts and aortas corresponded to echocardiographic images of valvular and supravalvular aortic obstruction and provided solid corroboration of echocardiographic diagnoses.

Optimizing logistics for balloon-occluded retrograde transvenous obliteration (BRTO) of gastric varices by doing away with the indwelling balloon: concept and techniques.

Science.gov (United States)

Saad, Wael E; Nicholson, David B

2013-06-01

Since the conception of balloon-occluded retrograde transvenous obliteration (BRTO) of gastric varices 25 years ago, the placement of an indwelling balloon for hours has been central to the BRTO procedure. Numerous variables and variations of the BRTO procedure have been described, including methods to reduce sclerosant, combining percutaneous transhepatic obliteration, varying sclerosant, and using multiple sclerosants within the same procedure. However, the consistent feature of BRTO has always remained the indwelling balloon. Placing an indwelling balloon over hours for the BRTO procedure is a logistical burden that taxes the interventional radiology team and hospital resources. Substituting the balloon with hardware (coils or Amplatzer vascular plugs [AVPs] or both) is technically feasible and its risks most likely correlate with gastrorenal shunt (GRS) size. The current authors use packed 0.018- or 0.035-in coils or both for small gastric variceal systems (GRS size A and B) and AVPs for GRS sizes up to size E (from size A-E). The current authors recommend an indwelling balloon (no hardware substitute) for very large gastric variceal system (GRS size F). Substituting the indwelling balloon for hardware in size F and potentially size E GRS can also be risky. The current article describes the techniques of placing up to 16-mm AVPs through balloon occlusion guide catheters and then deflating the balloon once it has been substituted with the AVPs. In addition, 22-mm AVPs can be placed through sheaths once the balloon occlusion catheters are removed to further augment the 16-mm Amplatzer occlusion. To date, there are no studies describing, let alone evaluating, the clinical feasibility of performing BRTO without indwelling balloons. The described techniques have been successfully performed by the current authors. However, the long-term safety and effectiveness of these techniques is yet to be determined. Copyright © 2013 Elsevier Inc. All rights reserved.

Unusual Case of Overt Aortic Dissection Mimicking Aortic Intramural Hematoma

Directory of Open Access Journals (Sweden)

Kushtrim Disha

2016-04-01

Full Text Available We report an interesting case in which overt aortic dissection mimicked two episodes of aortic intramural hematoma (IMH (Stanford A, DeBakey I. This took place over the course of four days and had a major influence on the surgical treatment strategy. The first episode of IMH regressed completely within 15 hours after it was clinically diagnosed and verified using imaging techniques. The recurrence of IMH was detected three days thereafter, resulting in an urgent surgical intervention. Overt aortic dissection with evidence of an intimal tear was diagnosed intraoperatively.

Supra-aortic interventions for endovascular exclusion of the entire aortic arch.

Science.gov (United States)

Andrási, Terézia B; Grossmann, Marius; Zenker, Dieter; Danner, Bernhard C; Schöndube, Friedrich A

2017-07-01

Our aim was to analyze the outcomes of endovascular exclusion of the entire aortic arch (proximal landing in zone 0, distal landing in zone III or beyond, after Ishimaru) in which complete surgical debranching of the supra-aortic vessels (I), endovascular supra-aortic revascularization (chimney, fenestrated, or branched grafts) with partial surgical debranching (II), or total endovascular supra-aortic revascularization (III) was additionally performed. Publications describing endovascular repair of the aortic arch (2000-2016) were systematically searched and reviewed. From a total of 53 relevant studies including 1853 patients, only 1021 patients undergoing 35 different total aortic arch procedures were found eligible for further evaluation and included in group I, II, or III (429, 190, and 402 patients, respectively). Overall early mortality was higher in group I vs groups II and III (P = .001; 1 - β = 95.6%) but exceeded in group III (18.6%) and group II (14.0%) vs group I (8.0%; P = .044; 1 - β = 57.4%) for diseases involving zone 0. Mortality was higher in all subgroups treated for zone 0 disease compared with corresponding subgroups treated for zone I to zone III disease. The incidence of cerebral ischemic events was increased in groups I and II vs group III (7.5% and 11% vs 1.7%; P = .0001) and correlated with early mortality (R 2  = .20; P = .033). The incidence of type II endoleaks and endovascular reintervention was similar between groups and correlated with each other (R 2  = .37; P = .004). Type Ia endoleak occurred more often in groups II and III than in group I (7.1% and 12.1% vs 5.8%; P = .023) and correlated with midterm mortality (R 2  = .53; P = .005). Retrograde type A dissection was low in all groups, whereas aneurysm growth was higher in group III (2.6%, 4.2%, 10.7%; P = .002), correlating with midterm mortality (R 2  = .311; P = .009). Surgical revision slightly correlated with surgical complications (R 2  = .18; P = .044

Aorto-right atrial fistula after ascending aortic replacement or aortic value replacement

International Nuclear Information System (INIS)

Zhi Aihua; Dai Ruping; Jiang Shiliang; Lu Bin

2012-01-01

Objective: To evaluate the CT features of aorto-right atrial fistula after aortic valve replacement (AVR) or ascending aortic replacement. Methods: Eighty-seven patients with aortic-right atrial fistula underwent CT after operation. The CT features were retrospectively analyzed. Fistula was measured according to maximum width of the shunt. Results: Aorto-right atrial fistula was detected in 87 patients after aortic valve replacement or ascending aortic replacement by CT scan. Among them, 25 patients were diagnosed as mild aorto-right atrial fistula, 47 patients as moderate, and 15 patients as severe. Thirty-seven patients underwent follow-up CT.Among them, 10 patients with mild to moderate aorto-right atrial fistula were considered to have complete regression, 8 patients with mild aorto-right atrial fistula considered to have incomplete regression, 14 patients with mild to moderate aorto-right atrial fistula considered to have stable condition, and 5 patients with moderate aorto-right atrial fistula considered to have progression at the 3-month follow-up. Conclusion: CT is a useful tool for defining aorto-right atrial fistula after AVR or ascending aortic replacement and for evaluating it in follow-up. (authors)

Traumatic Aortic Injury

Directory of Open Access Journals (Sweden)

Brianna Miner

2016-09-01

Full Text Available History of present illness: A 48-year-old male with unknown past medical history presents as a trauma after being hit by a car traveling approximately 25 miles per hour. On initial presentation, the patient is confused, combative, and not answering questions appropriately. The patient is hypotensive with a blood pressure of 68/40 and a heart rate of 50 beats per minute, with oxygen saturation at 96% on room air. FAST scan is positive for fluid in Morrison’s pouch, splenorenal space, and pericardial space. Significant findings: The initial chest x-ray showed an abnormal superior mediastinal contour (blue line, suggestive of a possible aortic injury. The CT angiogram showed extensive circumferential irregularity and outpouching of the distal aortic arch (red arrows compatible with aortic transection. In addition, there was a circumferential intramural hematoma, which extended through the descending aorta to the proximal infrarenal abdominal aorta (green arrow. There was also an extensive surrounding mediastinal hematoma extending around the descending aorta and supraaortic branches (purple arrows. Discussion: Traumatic aortic injury is a life-threatening event. The incidence of blunt thoracic aortic injury is low, between 1 to 2 percent of those patients with blunt thoracic trauma.1 However, approximately 80% of patients with traumatic aortic injury die at the scene.2 Therefore it is imperative to diagnose traumatic aortic injury in a timely fashion. The diagnosis can be difficult due to the non-specific signs and symptoms and other distracting injuries. Clinical suspicion should be based on the mechanism of the injury and the hemodynamic status of the patient. In any patient with blunt or penetrating trauma to the chest that is hemodynamically unstable, traumatic aortic injury should be on the differential. Chest x-ray can be used as a screening tool. A normal chest x-ray has a negative predictive value of approximately 97%. CTA chest is the

21 CFR 884.5050 - Metreurynter-balloon abortion system.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Metreurynter-balloon abortion system. 884.5050... Devices § 884.5050 Metreurynter-balloon abortion system. (a) Identification. A metreurynter-balloon abortion system is a device used to induce abortion. The device is inserted into the uterine cavity...

The role of aortic wall CT attenuation measurements for the diagnosis of acute aortic syndromes

Energy Technology Data Exchange (ETDEWEB)

Knollmann, Friedrich D., E-mail: friedrich.knollmann@ucdmc.ucdavis.edu [Department of Radiology, University of California, Davis, 4860 Y Street, Sacramento, CA 95817 (United States); Departments of Radiology and Cardiothoracic Surgery, University of Pittsburgh, 200 Lothrop Street, Pittsburgh, PA 15213 (United States); Lacomis, Joan M.; Ocak, Iclal; Gleason, Thomas [Department of Radiology, University of California, Davis, 4860 Y Street, Sacramento, CA 95817 (United States); Departments of Radiology and Cardiothoracic Surgery, University of Pittsburgh, 200 Lothrop Street, Pittsburgh, PA 15213 (United States)

2013-12-01

Objectives: To determine if measurements of aortic wall attenuation can improve the CT diagnosis of acute aortic syndromes. Methods: CT reports from a ten year period were searched for acute aortic syndromes (AAS). Studies with both an unenhanced and a contrast enhanced (CTA) series that had resulted in the diagnosis of intramural hematoma (IMH) were reviewed. Diagnoses were confirmed by medical records. The attenuation of aortic wall abnormalities was measured. The observed attenuation threshold was validated using studies from 39 new subjects with a variety of aortic conditions. Results: The term “aortic dissection” was identified in 1206, and IMH in 124 patients’ reports. IMH was confirmed in 31 patients, 21 of whom had both unenhanced and contrast enhanced images. All 21 had pathologic CTA findings, and no CTA with IMH was normal. Attenuation of the aortic wall was greater than 45 HUs on the CTA images in all patients with IMH. When this threshold was applied to the new group, sensitivity for diagnosing AAS was 100% (19/19), and specificity 94% (16/17). Addition of unenhanced images did not improve accuracy. Conclusions: Measurements of aortic wall attenuation in CTA have a high negative predictive value for the diagnosis of acute aortic syndromes.

The role of aortic wall CT attenuation measurements for the diagnosis of acute aortic syndromes

International Nuclear Information System (INIS)

Knollmann, Friedrich D.; Lacomis, Joan M.; Ocak, Iclal; Gleason, Thomas

2013-01-01

Objectives: To determine if measurements of aortic wall attenuation can improve the CT diagnosis of acute aortic syndromes. Methods: CT reports from a ten year period were searched for acute aortic syndromes (AAS). Studies with both an unenhanced and a contrast enhanced (CTA) series that had resulted in the diagnosis of intramural hematoma (IMH) were reviewed. Diagnoses were confirmed by medical records. The attenuation of aortic wall abnormalities was measured. The observed attenuation threshold was validated using studies from 39 new subjects with a variety of aortic conditions. Results: The term “aortic dissection” was identified in 1206, and IMH in 124 patients’ reports. IMH was confirmed in 31 patients, 21 of whom had both unenhanced and contrast enhanced images. All 21 had pathologic CTA findings, and no CTA with IMH was normal. Attenuation of the aortic wall was greater than 45 HUs on the CTA images in all patients with IMH. When this threshold was applied to the new group, sensitivity for diagnosing AAS was 100% (19/19), and specificity 94% (16/17). Addition of unenhanced images did not improve accuracy. Conclusions: Measurements of aortic wall attenuation in CTA have a high negative predictive value for the diagnosis of acute aortic syndromes

Balloon launching station, Mildura, Victoria

International Nuclear Information System (INIS)

The Mildura Balloon Launching Station was established in 1960 by the Department of Supply (now the Department of Manufacturing Industry) on behalf of the United States Atomic Energy Commission (USAEC) to determine the content of radioactive material in the upper atmosphere over Australia. The Station location and layout, staffing, balloon launching equipment, launching, tracking and recovery are described. (R.L.)

3D echocardiographic analysis of aortic annulus for transcatheter aortic valve replacement using novel aortic valve quantification software: Comparison with computed tomography.

Science.gov (United States)

Mediratta, Anuj; Addetia, Karima; Medvedofsky, Diego; Schneider, Robert J; Kruse, Eric; Shah, Atman P; Nathan, Sandeep; Paul, Jonathan D; Blair, John E; Ota, Takeyoshi; Balkhy, Husam H; Patel, Amit R; Mor-Avi, Victor; Lang, Roberto M

2017-05-01

With the increasing use of transcatheter aortic valve replacement (TAVR) in patients with aortic stenosis (AS), computed tomography (CT) remains the standard for annulus sizing. However, 3D transesophageal echocardiography (TEE) has been an alternative in patients with contraindications to CT. We sought to (1) test the feasibility, accuracy, and reproducibility of prototype 3DTEE analysis software (Philips) for aortic annular measurements and (2) compare the new approach to the existing echocardiographic techniques. We prospectively studied 52 patients who underwent gated contrast CT, procedural 3DTEE, and TAVR. 3DTEE images were analyzed using novel semi-automated software designed for 3D measurements of the aortic root, which uses multiplanar reconstruction, similar to CT analysis. Aortic annulus measurements included area, perimeter, and diameter calculations from these measurements. The results were compared to CT-derived values. Additionally, 3D echocardiographic measurements (3D planimetry and mitral valve analysis software adapted for the aortic valve) were also compared to the CT reference values. 3DTEE image quality was sufficient in 90% of patients for aortic annulus measurements using the new software, which were in good agreement with CT (r-values: .89-.91) and small (software can accurately measure aortic annulus in patients with severe AS undergoing TAVR, in better agreement with CT than the existing methodology. Accordingly, intra-procedural TEE could potentially replace CT in patients where CT carries significant risk. © 2017, Wiley Periodicals, Inc.

Dynamics of the aortic annulus in 4D CT angiography for transcatheter aortic valve implantation patients

NARCIS (Netherlands)

Elattar, Mustafa A.; Vink, Leon W.; van Mourik, Martijn S.; Baan, Jan; Vanbavel, Ed T.; Planken, R. Nils; Marquering, Henk A.

2017-01-01

Transcatheter aortic valve implantation (TAVI) is a well-established treatment for patients with severe aortic valve stenosis. This procedure requires pre-operative planning by assessment of aortic dimensions on CT Angiography (CTA). It is well-known that the aortic root dimensions vary over the

Initial clinical experience with a sac-anchoring endoprosthesis for aortic aneurysm repair.

Science.gov (United States)

Donayre, Carlos E; Zarins, Christopher K; Krievins, Dainis K; Holden, Andrew; Hill, Andrew; Calderas, Carlos; Velez, Jaime; White, Rodney A

2011-03-01

All current aortic endografts depend on proximal and distal fixation to prevent migration. However, migration and rupture can occur, particularly in patients with aortic necks that are short or angulated, or both. We present our initial clinical experience with a new sac-anchoring endoprosthesis designed to anchor and seal the device within the aneurysm sac. The initial worldwide experience using a new endoprosthesis for the treatment of aortic aneurysms (Nellix Endovascular, Palo Alto, Calif) was reviewed. The endoprosthesis consists of dual balloon-expandable endoframes surrounded by polymer-filled endobags designed to obliterate the aneurysm sac and maintain endograft position. Clinical results and follow-up contrast computed tomography (CT) scans at 30 days and 6 and 12 months were reviewed. The endograft was successfully deployed in 21 patients with infrarenal aortic aneurysms measuring 5.7 ± 0.7 cm (range, 4.3-7.4 cm). Two patients with common iliac aneurysms were treated with sac-anchoring extenders that maintained patency of the internal iliac artery. Infusion of 71 ± 37 mL of polymer (range, 19-158 mL) into the aortic endobags resulted in complete aneurysm exclusion in all patients. Mean implant time was 76 ± 35 minutes, with 33 ± 17 minutes of fluoroscopy time and 180 ± 81 mL of contrast; estimated blood loss was 174 ± 116 mL. One patient died during the postoperative period (30-day mortality, 4.8%), and one died at 10 months from non-device-related causes. During a mean follow-up of 8.7 ± 3.1 months and a median of 6.3 months, there were no late aneurysm- or device-related adverse events and no secondary procedures. CT imaging studies at 6 months and 1 year revealed no increase in aneurysm size, no device migration, and no new endoleaks. One patient had a limited proximal type I endoleak at 30 days that resolved at 60 days and remained sealed. One patient has an ongoing distal type I endoleak near the iliac bifurcation, with no change in aneurysm

Anatomic changes of target vessels after fenestrated and branched aortic aneurysm repair.

Science.gov (United States)

Kalder, J; Keschenau, P; Tamm, M; Jalaie, H; Jacobs, M J; Greiner, A

2014-04-01

Objective of this study was to evaluate the anatomic changes of the stented target vessels after endovascular repair of complex aortic aneurysms. Between July 2011 and December 2013, 53 aortic aneurysms were treated in our department with fenestrated and branched stent-graft devices. Forty-two of these patients were pre- and postoperatively scanned with a high resolution computer tomography (CT) (Cook Zenith® fenestrated or branched, Australia Pty. Ltd., Brisbane, Australia: N.=19; AnacondaTM fenestrated, Vascutek, Glasgow, Scotland, UK: N.=23). The other 11 out of the 53 patients did not receive a CT scan, because of a pre-existing renal failure. In the CT scans we retrospectively evaluated the anatomic vessel deviation at the origin of the target vessel and the vessel shift distal to the stent. For the first measurement the CT scans were loaded into OsiriX MD®, and the pre- and postoperative angles of the target vessels were measured and subtracted. For matching, the CT-scans were normalized at vertebral body lumbar 2. The second measured angle was the maximal measured angle distal to the target vessel stent-graft. Altogether, 113 target vessels were stented (celiac trunk [CT] 15, superior mesenteric arteries [SMA] 26, renal arteries [RA] 72), with 97 balloon-expandable PTFE stents: 90 Atrium V12 (Maquet Getinge group, Hudson, NH, USA), 7 BeGrafts (Bentley InnoMed, Hechingen, Germany) and 16 self-expandable fluency PTFE stents (Bard, Karlsruhe, Germany). The mean anatomic deviation at the target vessel origin was 28±17.3 and the mean vessel shift distal to the stent was 36.3±18.8. There were no significant differences between the main device and the target vessel stent types. Fenestrated and branched stent-graft solutions for aortic aneurysm repair induce changes of the target vessel anatomy. We did not observe significant differences between the several devices.

Pathogenetic Basis of Aortopathy and Aortic Valve Disease

Science.gov (United States)

2018-02-19

Aortopathies; Thoracic Aortic Aneurysm; Aortic Valve Disease; Thoracic Aortic Disease; Thoracic Aortic Dissection; Thoracic Aortic Rupture; Ascending Aortic Disease; Descending Aortic Disease; Ascending Aortic Aneurysm; Descending Aortic Aneurysm; Marfan Syndrome; Loeys-Dietz Syndrome; Ehlers-Danlos Syndrome; Shprintzen-Goldberg Syndrome; Turner Syndrome; PHACE Syndrome; Autosomal Recessive Cutis Laxa; Congenital Contractural Arachnodactyly; Arterial Tortuosity Syndrome

Transcatheter aortic valve implantation: durability of clinical and hemodynamic outcomes beyond 3 years in a large patient cohort.

Science.gov (United States)

Gurvitch, R; Wood, D A; Tay, E L; Leipsic, J; Ye, J; Lichtenstein, S V; Thompson, C R; Carere, R G; Wijesinghe, N; Nietlispach, F; Boone, R H; Lauck, S; Cheung, A; Webb, J G

2010-09-28

Although short- and medium-term outcomes after transcatheter aortic valve implantation are encouraging, long-term data on valve function and clinical outcomes are limited. Consecutive high-risk patients who had been declined as surgical candidates because of comorbidities but who underwent successful transcatheter aortic valve implantation with a balloon-expandable valve between January 2005 and December 2006 and survived past 30 days were assessed. Clinical, echocardiographic, and computed tomographic follow-up examinations were performed. Seventy patients who underwent successful procedures and survived longer than 30 days were evaluated at a minimum follow-up of 3 years. At a median follow-up of 3.7 years (interquartile range 3.4 to 4.3 years), survival was 57%. Survival at 1, 2, and 3 years was 81%, 74%, and 61%, respectively. Freedom from reoperation was 98.5% (1 patient with endocarditis). During this early procedural experience, 11 patients died within 30 days, and 8 procedures were unsuccessful. When these patients were included, overall survival was 51%. Transaortic pressure gradients increased from 10.0 mm Hg (interquartile range 8.0 to 12.0 mm Hg) immediately after the procedure to 12.1 mm Hg (interquartile range 8.6 to 16.0 mm Hg) after 3 years (P=0.03). Bioprosthetic valve area decreased from a mean of 1.7±0.4 cm(2) after the procedure to 1.4±0.3 cm(2) after 3 years (Pfracture, deformation, or valve migration. Transcatheter aortic valve implantation demonstrates good medium- to long-term durability and preserved hemodynamic function, with no evidence of structural failure. The procedure appears to offer an adequate and lasting resolution of aortic stenosis in selected patients.

Systematic Design of a Magnetically Levitated Brushless DC Motor for a Reversible Rotary Intra-Aortic Blood Pump.

Science.gov (United States)

Wang, Yaxin; Logan, Thomas G; Smith, P Alex; Hsu, Po-Lin; Cohn, William E; Xu, Liping; McMahon, Richard A

2017-10-01

The IntraVAD is a miniature intra-aortic ventricular assist device (VAD) designed to work in series with the compromised left ventricle. A reverse-rotation control (RRc) mode has been developed to increase myocardial perfusion and reduce ventricular volume. The RRc mode includes forward rotation in systole and reverse rotation in diastole, which requires the IntraVAD to periodically reverse its rotational direction in synchrony with the cardiac cycle. This periodic reversal leads to changes in pressure force over the impeller, which makes the entire system less stable. To eliminate the mechanical wear of a contact bearing and provide active control over the axial position of the rotor, a miniature magnetically levitated bearing (i.e., the PM-Coil module) composed of two concentric permanent magnetic (PM) rings and a pair of coils-one on each side-was proposed to provide passive radial and active axial rotor stabilization. In the early design stage, the numerical finite element method (FEM) was used to optimize the geometry of the brushless DC (BLDC) motor and the maglev module, but constructing a new model each time certain design parameters were adjusted required substantial computation time. Because the design criteria for the module had to be modified to account for the magnetic force produced by the motor and for the hemodynamic changes associated with pump operation, a simplified analytic expression was derived for the expected magnetic forces. Suitable bearings could then be designed capable of overcoming these forces without repeating the complicated FEM simulation for the motor. Using this method at the initial design stage can inform the design of the miniature maglev BLDC motor for the proposed pulsatile axial-flow VAD. © 2017 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Bioprosthetic Valve Fracture to Facilitate Transcatheter Valve-in-Valve Implantation.

Science.gov (United States)

Allen, Keith B; Chhatriwalla, Adnan K; Cohen, David J; Saxon, John T; Aggarwal, Sanjeev; Hart, Anthony; Baron, Suzanne; Davis, J Russell; Pak, Alex F; Dvir, Danny; Borkon, A Michael

2017-11-01

Valve-in-valve transcatheter aortic valve replacement is less effective in small surgical bioprostheses. We evaluated the feasibility of bioprosthetic valve fracture with a high-pressure balloon to facilitate valve-in-valve transcatheter aortic valve replacement. In vitro bench testing on aortic tissue valves was performed on 19-mm and 21-mm Mitroflow (Sorin, Milan, Italy), Magna and Magna Ease (Edwards Lifesciences, Irvine, CA), Trifecta and Biocor Epic (St. Jude Medical, Minneapolis, MN), and Hancock II and Mosaic (Medtronic, Minneapolis, MN). High-pressure balloons Tru Dilation, Atlas Gold, and Dorado (C.R. Bard, Murray Hill, NJ) were used to determine which valves could be fractured and at what pressure fracture occurred. Mitroflow, Magna, Magna Ease, Mosaic, and Biocor Epic surgical valves were successfully fractured using high-pressures balloon 1 mm larger than the labeled valve size whereas Trifecta and Hancock II surgical valves could not be fractured. Only the internal valve frame was fractured, and the sewing cuff was never disrupted. Manufacturer's rated burst pressures for balloons were exceeded, with fracture pressures ranging from 8 to 24 atmospheres depending on the surgical valve. Testing further demonstrated that fracture facilitated the expansion of previously constrained, underexpanded transcatheter valves (both balloon and self-expanding) to the manufacturer's recommended size. Bench testing demonstrates that the frame of most, but not all, bioprosthetic surgical aortic valves can be fractured using high-pressure balloons. The safety of bioprosthetic valve fracture to optimize valve-in-valve transcatheter aortic valve replacement in small surgical valves requires further clinical investigation. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Thoracic Endovascular Aortic Repair (TEVAR) in Proximal (Type A) Aortic Dissection: Ready for a Broader Application?

OpenAIRE

Nienaber, Christoph A.; Sakalihasan, Natzi; Clough, Rachel E.; Aboukoura, Mohamed; Mancuso, Enrico; Yeh, James S.M.; Defraigne, Jean-Olivier; Cheshire, Nick; Rosendahl, Ulrich Peter; Quarto, Cesare; Pepper, John

2016-01-01

ObjectiveThoracic endovascular aortic repair (TEVAR) has demonstrated encouraging results and is gaining increasing acceptance as a treatment option for aortic aneurysms and dissections. Yet, its role in managing proximal aortic pathologies is unknown - this is important because in proximal (Stanford type A) aortic dissections, 10-30% are not accepted for surgery, and 30-50% are technically amenable for TEVAR. We describe our case series of type A aortic dissections treated using TEVAR.Method...

[Balloon cell nevi of the conjunctiva (author's transl)].

Science.gov (United States)

Schlageter, P E; Daicker, B

1975-06-01

The clinical and histological features of three cases of conjunctival balloon cell nevi are described. This peculiar form of nevus is very rare in the conjunctiva. The findings are compared with the descriptions in the literature of dermal balloon cell nevi. They demonstrate, that the conjunctival and dermal tumours are of idential histological structure. The proliferations of the conjunctival epithelium often found in conjunctival nevi do not modify the balloon cell nevi. These can not be diagnosed clinically. The problems of the pathogenesis of the balloon cell nevi are discussed.

Simulating clefts in pumpkin balloons

Science.gov (United States)

Baginski, Frank; Brakke, Kenneth

2010-02-01

The geometry of a large axisymmetric balloon with positive differential pressure, such as a sphere, leads to very high film stresses. These stresses can be significantly reduced by using a tendon re-enforced lobed pumpkin-like shape. A number of schemes have been proposed to achieve a cyclically symmetric pumpkin shape, including the constant bulge angle (CBA) design, the constant bulge radius (CBR) design, CBA/CBR hybrids, and NASA’s recent constant stress (CS) design. Utilizing a hybrid CBA/CBR pumpkin design, Flight 555-NT in June 2006 formed an S-cleft and was unable to fully deploy. In order to better understand the S-cleft phenomenon, a series of inflation tests involving four 27-m diameter 200-gore pumpkin balloons were conducted in 2007. One of the test vehicles was a 1/3-scale mockup of the Flight 555-NT balloon. Using an inflation procedure intended to mimic ascent, the 1/3-scale mockup developed an S-cleft feature strikingly similar to the one observed in Flight 555-NT. Our analysis of the 1/3-scale mockup found it to be unstable. We compute asymmetric equilibrium configurations of this balloon, including shapes with an S-cleft feature.

Spontaneous perforation of a syphilitic aneurysm of the aortic arch into the pulmonary artery

International Nuclear Information System (INIS)

Stampfel, G.

1983-01-01

An aortopulmonary fistula in case of a bag-shaped aneurysm of the aortic arch is demonstrated via angiography. A diagnosis to the effect that the existence of this phenomenon is suspected, can already be arrived at when examining the plain radiography of the thorax. We can say that a sign of an aortopulmonary fistula is represented, in case of an aneurysm of the aorta ascendens and of the arcus aortae, by the existence of a left-right shunt with hypercirculation in the pulmonary circulation, in most cases also signs of right ventricular insufficiency. This is often combined with a typical previous history of sudden dyspnoeas and thoracic pain. The article points out the theoretical possibility of balloon catheter occlusion of the fistula to relieve the acute right ventricular load. (orig.) [de

Stroke Volume estimation using aortic pressure measurements and aortic cross sectional area: Proof of concept.

Science.gov (United States)

Kamoi, S; Pretty, C G; Chiew, Y S; Pironet, A; Davidson, S; Desaive, T; Shaw, G M; Chase, J G

2015-08-01

Accurate Stroke Volume (SV) monitoring is essential for patient with cardiovascular dysfunction patients. However, direct SV measurements are not clinically feasible due to the highly invasive nature of measurement devices. Current devices for indirect monitoring of SV are shown to be inaccurate during sudden hemodynamic changes. This paper presents a novel SV estimation using readily available aortic pressure measurements and aortic cross sectional area, using data from a porcine experiment where medical interventions such as fluid replacement, dobutamine infusions, and recruitment maneuvers induced SV changes in a pig with circulatory shock. Measurement of left ventricular volume, proximal aortic pressure, and descending aortic pressure waveforms were made simultaneously during the experiment. From measured data, proximal aortic pressure was separated into reservoir and excess pressures. Beat-to-beat aortic characteristic impedance values were calculated using both aortic pressure measurements and an estimate of the aortic cross sectional area. SV was estimated using the calculated aortic characteristic impedance and excess component of the proximal aorta. The median difference between directly measured SV and estimated SV was -1.4ml with 95% limit of agreement +/- 6.6ml. This method demonstrates that SV can be accurately captured beat-to-beat during sudden changes in hemodynamic state. This novel SV estimation could enable improved cardiac and circulatory treatment in the critical care environment by titrating treatment to the effect on SV.

Upper gastrointestinal strictures: The results of balloon dilatation

Energy Technology Data Exchange (ETDEWEB)

Lee, Kil Woo; Lim, Hyo Keun; Choo, In Wook; Bae, Sang Hoon; Yoon, Jong Sup [Hallym University College of Medicine, Seoul (Korea, Republic of); Yoo, Hyung Sik [Yonsei University College of Medicine, Seoul (Korea, Republic of)

1990-12-15

Balloon catheter dilatation of upper gastrointestinal strictures is an accepted mode of therapy. The authors report the balloon dilatation in 11 consecutive patients. The lesions treated included 10 benign strictures, and 1 esophageal cancer. Esophageal balloon were ranged from 2 mm in diameter, 4 cm in length, to 30 mm in diameter, 8 cm in length. Inflation was held for from 30 to 60 seconds and then repeated two or three times during each session. The balloons were inflated to pressure of from 2 to 12 atmospheres. There were from 1 to 13 dilatations. Two esophageal perforations were occurred in one esophagitis patient and other lye stricture patient. Two perforations were not required any surgical repair. All dilatation were performed without anesthesia. All strictures were responded immediately to dilatation. Prolonged course of treatment were needed with chronic severe esophagitis, lye stricture, gastrojejunostomy with chemotherapy, as a result, all patients, except esophageal cancer, could take regular diet after balloon catheter dilatation. Balloon catheter dilatation of upper gastrointestinal stenosis was effective and safe. It should be considered before other methods of treatment applicable.

Percutaneous balloon dilation of pulmonary stenosis

International Nuclear Information System (INIS)

Hua Yangde; Huang Ming; Li Jinkang; Qian Jinqing; Chen Xiuyu; Yang Siyuan

2003-01-01

Objective: Review our experience of balloon dilation of valvular pulmonary stenosis in 32 cases. Methods: Totally 32 cases of pulmonary stenosis admitted from 1995-2001 with age of 1.5-13 yrs mean 6.8. Diagnosis was made by clinical manifestations, EKG, ECHO and angiocardiography. Results: Before dilation, the mean systolic pressure of right ventricle was (93.5 ± 28.5) mmHg, after the procedure it reduced to (42 ± 9.0) mmHg. The pressure gradient between right ventricle and pulmonary artery before dilation was (76 ± 30) mmHg and become (24.5 ± 8.5) mmHg after dilation. The gradient pressure after dilation was less than 25 mmHg in 90.6% cases. A case of Noonan syndrome showed no response to balloon dilation and died during valvulectomy from accompanying left ventricular cardiomyopathy. Conclusions: Balloon dilation of valvular pulmonary stenosis is effective and safe. The selection of proper diameter of pulmonary valvular rings and sized of the balloon are the major factors

Aortic root reconstruction by aortic valve-sparing operation (David type I reimplantation) in Marfan syndrome accompanied by annuloaortic ectasia and acute type-A aortic dissection.

Science.gov (United States)

Inamura, Shunichi; Furuya, Hidekazu; Yagi, Kentarou; Ikeya, Eriko; Yamaguchi, Masaomi; Fujimura, Takabumi; Kanabuchi, Kazuo

2006-09-20

To reconstruct the aortic root for aneurysm of the ascending aorta accompanied by aortic regurgitation, annuloaortic ectasia (AAE) and acute type-A dissection with root destruction, the Bentall operation using a prosthetic valve still is the standard procedure today. Valve-sparing procedures have actively been used for aortic root lesions, and have also been attempted in aortic root reconstruction for Marfan syndrome which may have abnormalities in the valve leaflets. We conducted a valve-sparing procedure in a female patient with Marfan syndrome who had AAE accompanied by type-A acute aortic dissection. The patient was a 37-year-old woman complaining of severe pain from the chest to the back. The limbs were long, and funnel breast was observed. Diastolic murmurs were heard. On chest computed tomography, a dissection cavity was present from the ascending aorta to the left common iliac artery, and the root dilated to 55 mm. Grade II aortic regurgitation was observed on ultrasound cardiography. Regarding her family history, her father had died suddenly at 54 years of age. She was diagnosed with type-A acute dissection concurrent with Marfan syndrome and AAE. The structure of the aortic valve was normal, and root reconstruction by a valve-sparing operation and total replacement of the aortic arch was conducted. On postoperative ultrasound cardiography, the aortic regurgitation was within the allowable range, and the shortterm postoperative results were good.

Microarray analysis to identify the similarities and differences of pathogenesis between aortic occlusive disease and abdominal aortic aneurysm.

Science.gov (United States)

Wang, Guofu; Bi, Lechang; Wang, Gaofeng; Huang, Feilai; Lu, Mingjing; Zhu, Kai

2018-06-01

Objectives Expression profile of GSE57691 was analyzed to identify the similarities and differences between aortic occlusive disease and abdominal aortic aneurysm. Methods The expression profile of GSE57691 was downloaded from Gene Expression Omnibus database, including 20 small abdominal aortic aneurysm samples, 29 large abdominal aortic aneurysm samples, 9 aortic occlusive disease samples, and 10 control samples. Using the limma package in R, the differentially expressed genes were screened. Followed by enrichment analysis was performed for the differentially expressed genes using database for annotation, visualization, and integrated discovery online tool. Based on string online tool and Cytoscape software, protein-protein interaction network and module analyses were carried out. Moreover, integrated TF platform database and Cytoscape software were used for constructing transcriptional regulatory networks. Results As a result, 1757, 354, and 396 differentially expressed genes separately were identified in aortic occlusive disease, large abdominal aortic aneurysm, and small abdominal aortic aneurysm samples. UBB was significantly enriched in proteolysis related pathways with a high degree in three groups. SPARCL1 was another gene shared by these groups and regulated by NFIA, which had a high degree in transcriptional regulatory network. ACTB, a significant upregulated gene in abdominal aortic aneurysm samples, could be regulated by CLIC4, which was significantly enriched in cell motions. ACLY and NFIB were separately identified in aortic occlusive disease and small abdominal aortic aneurysm samples, and separately enriched in lipid metabolism and negative regulation of cell proliferation. Conclusions The downregulated UBB, NFIA, and SPARCL1 might play key roles in both aortic occlusive disease and abdominal aortic aneurysm, while the upregulated ACTB might only involve in abdominal aortic aneurysm. ACLY and NFIB were specifically involved in aortic occlusive

Stability of the pumpkin balloon

Science.gov (United States)

Baginski, Frank

A large axisymmetric balloon with positive differential pressure, e.g., a sphere, leads to high film stresses. These can be significantly reduced by using a lobed pumpkin-like shape re-enforced with tendons. A number of schemes have been proposed to achieve a cyclically symmetric pumpkin-shape at full inflation, including the constant bulge angle (CBA) design and the constant bulge radius (CBR) design. The authors and others have carried out stability studies of CBA and CBR designs and found instabilities under various conditions. While stability seems to be a good indicator of deployment problems for large balloons under normal ascent conditions, one cannot conclude that a stable design will deploy reliably. Nevertheless, stability analysis allows one to quantify certain deployment characteristics. Ongoing research by NASA's Balloon Program Office utilizes a new design approach developed by Rodger Farley, NASA/GSFC, that takes into account film and tendon strain. We refer to such a balloon as a constant stress (CS) pumpkin design. In June 2006, the Flight 555-NT balloon (based on a hybrid CBR/CBA design) developed an S-cleft and did not deploy. In order to understand the S-cleft phenomena and study a number of aspects related to the CS-design, a series of inflation tests were conducted at TCOM, Elizabeth City, NC in 2007. The test vehicles were 27 meter diameter pumpkins distinguished by their respective equatorial bulge angles (BA). For example, BA98 indicates an equatorial bulge angle of 98° . BA90, BA55, and BA00 are similarly defined. BA98 was essentially a one-third scale version of of the Flight 555 balloon (i.e., 12 micron film instead of 38.1 micron, mini-tendons, etc.). BA90 and BA55 were Farley CS-designs. BA00 was derived from the BA55 design so that a flat chord spanned adjacent tendons. In this paper, we will carry out stability studies of BA98, BA90, BA55, and BA00. We discuss the deployment problem of pumpkin balloons in light of 2007 inflation

Abdominal aortic aneurysm development in men following a "normal" aortic ultrasound scan.

Science.gov (United States)

Hafez, H; Druce, P S; Ashton, H A

2008-11-01

To determine predictors related to abdominal aortic aneurysm (AAA) development following a "normal" aortic ultrasound scan. Over a 23-year period, 22 961 men participated in an AAA screening programme. Maximum aortic diameter of less than 30 mm was deemed "normal". 4308 of these "normal" individuals were later re-scanned at intervals for research purposes. AAA prevalence was 4.4% at initial scanning. In those with a normal scan, 46 patients subsequently presented with AAAs incidentally detected and 120 (2.8%) had AAAs identified as part of the ongoing surveillance. The median initial aortic size of these 166 men was 25 mm (range 15-29 mm). Over the follow-up period, there have been 24 (14%) AAA-related deaths, 24 patients underwent successful AAA surgery and 36 died of unrelated causes. In those with an initial aortic diameter of <25 mm who later developed an AAA, the odds ratio for AAA-related mortality was 2 (95% CI 1-4.1, p=0.03, x(2)). AAAs can develop following an initial "normal" scan and men with an aortic diameters of 25-29 mm appear to be at greater risk. Surveillance for this sub-group may further reduce the incidence of undiagnosed AAA and AAA-related mortality.

Balloon dilatation of ureteric strictures.

Directory of Open Access Journals (Sweden)

Punekar S

2000-01-01

Full Text Available AIMS: Evaluation of dilatation as a minimally invasive technique for the treatment of ureteric strictures. MATERIAL AND METHODS: We evaluated this technique in 16 patients with ureteric and secondary pelviureteric junction strictures from June 1998. Of these, 7 were men and 9 were women. The age range was from 14 to 40 years. RESULTS: Balloon dilatation was successful in 69% of patients. Strictures secondary to previous surgery had nearly 100% success. Of the 8 cases diagnosed as genitourinary tuberculosis, success rate was 50%. CONCLUSIONS: Factors affecting success of balloon dilatation are: a age of the stricture b length of the stricture and c etiology of the stricture. In a select group of patients with fresh post-operative or post-inflammatory strictures, balloon dilatation may be an attractive alternative to surgery.

Na,K-pump modulates intercellular communication in vascular wall

DEFF Research Database (Denmark)

Matchkov, Vladimir

were used as a model for electrical coupling of SMCs by measuring membrane capacitance (Cm). SMCs were uncoupled (evaluated by inhibition of vasomotion and desynchronization of calcium transients in vascular wall, or by reduction to half of Cm measured in paired A7r5 cells) when the Na......  Ouabain, a specific inhibitor of the Na,K-pump, has previously been shown to interfere with intercellular communication. Here we test the hypothesis that the communication between vascular smooth muscle cells (SMCs) is regulated through an interaction between the Na,K-pump and the Na......,Ca-exchanger leading to an increase in the intracellular calcium concentration in discrete areas near the plasma membrane. The intracellular calcium concentration in individual SMCs was imaged in cultured rat aortic SMCs (A7r5) and simultaneously with isometric force in rat mesenteric small arteries. Paired A7r5 cells...

Multimodality Imaging Approach towards Primary Aortic Sarcomas Arising after Endovascular Abdominal Aortic Aneurysm Repair: Case Series Report

Energy Technology Data Exchange (ETDEWEB)

Kamran, Mudassar, E-mail: kamranm@mir.wustl.edu; Fowler, Kathryn J., E-mail: fowlerk@mir.wustl.edu; Mellnick, Vincent M., E-mail: mellnickv@mir.wustl.edu [Washington University School of Medicine, Mallinckrodt Institute of Radiology (United States); Sicard, Gregorio A., E-mail: sicard@wudosis.wustl.edu [Washington University School of Medicine, Department of Surgery (United States); Narra, Vamsi R., E-mail: narrav@mir.wustl.edu [Washington University School of Medicine, Mallinckrodt Institute of Radiology (United States)

2016-06-15

Primary aortic neoplasms are rare. Aortic sarcoma arising after endovascular aneurysm repair (EVAR) is a scarce subset of primary aortic malignancies, reports of which are infrequent in the published literature. The diagnosis of aortic sarcoma is challenging due to its non-specific clinical presentation, and the prognosis is poor due to delayed diagnosis, rapid proliferation, and propensity for metastasis. Post-EVAR, aortic sarcomas may mimic other more common aortic processes on surveillance imaging. Radiologists are rarely knowledgeable about this rare entity for which multimodality imaging and awareness are invaluable in early diagnosis. A series of three pathologically confirmed cases are presented to display the multimodality imaging features and clinical presentations of aortic sarcoma arising after EVAR.

Bovine aortic arch with supravalvular aortic stenosis

Directory of Open Access Journals (Sweden)

Mohammed Idhrees

2016-09-01

Full Text Available A 5-year-old boy was diagnosed to have supravalvular aortic stenosis (SVAS. On evaluation of CT angiogram, there was associated bovine aortic arch (BAA. Association of BAA with SVAS has not been previously reported in literature, and to best of our knowledge, this is the first case report of SVAS with BAA. Recent studies show BAA as a marker for aortopathy. SVAS is also an arteriopathy. In light of this, SVAS can also possibly be a manifestation of aortopathy associated with BAA.

Indexing aortic valve area by body surface area increases the prevalence of severe aortic stenosis

DEFF Research Database (Denmark)

Jander, Nikolaus; Gohlke-Bärwolf, Christa; Bahlmann, Edda

2014-01-01

To account for differences in body size in patients with aortic stenosis, aortic valve area (AVA) is divided by body surface area (BSA) to calculate indexed AVA (AVAindex). Cut-off values for severe stenosis are......To account for differences in body size in patients with aortic stenosis, aortic valve area (AVA) is divided by body surface area (BSA) to calculate indexed AVA (AVAindex). Cut-off values for severe stenosis are...

Current indications for stentless aortic bioprostheses.

Science.gov (United States)

Hegazy, Yasser Y; Rayan, Amr; Bauer, Stefan; Keshk, Noha; Bauer, Kerstin; Ennker, Ina; Ennker, Jürgen

2018-01-01

The best aortic prostheses have been debated for decades. The introduction of stentless aortic bioprostheses was aimed at improving hemodynamics and potentially the durability of aortic bioprostheses. Despite the good short- and long-term outcomes after implantation of stentless aortic bioprostheses, their use remains limited owing to the technically demanding implantation techniques. Nevertheless, stentless aortic bioprostheses might be of special benefit in certain indications, where they could be a valuable addition to the surgical armamentarium.

Properties of ballooning modes in the Heliotron configurations

International Nuclear Information System (INIS)

Nakajima, N.; Hudson, S.R.; Hegna, C.C.

2005-01-01

The stability of ballooning modes is influenced by the local and global magnetic shear and local and global magnetic curvature so significantly that it is fairly difficult to get those general properties in the three dimensional configurations with strong flexibility due to the external coil system. In the case of the planar axis heliotron configurations allowing a large Shafranov shift, like LHD, properties of the high-mode-number ballooning modes have been intensively investigated. It has been analytically shown that the local magnetic shear comes to disappear in the stellarator-like global magnetic shear region, as the Shafranov shift becomes large. Based on this mechanism and the characteristics of the local and global magnetic curvature, it is numerically shown that the destabilized ballooning modes have strong three-dimensional properties (both poloidal and toroidal mode couplings) in the Mercier stable region, and that those are fairly similar to ballooning modes in the axisymmetric system in the Mercier unstable region. As is well known, however, no quantization condition is applicable to the ballooning modes in the three-dimensional system without symmetry, and so the results of the high-mode-number ballooning modes in the covering space had to be confirmed in the real space. Such a confirmation has been done in the Mercier stable region and also in the Mercier unstable region by using three dimensional linearized ideal MHD stability code cas3d. Confirming the relation between high-mode-number ballooning analyses by the global mode analyses, the method of the equilibrium profile variations has been developed in the tree dimensional system, giving dt/dψ - dP/dψ stability diagram corresponding to the s - α diagram in tokamaks. This method of profile variation are very powerful to investigate the second stability of high-mode-number ballooning modes and has been more developed. Recently it has been applied to the plasma in the inward-shifted LHD

The Balloon-Based Manometry Evaluation of Swallowing in Patients with Amyotrophic Lateral Sclerosis

Directory of Open Access Journals (Sweden)

Jerzy Tomik

2017-03-01

Full Text Available The aim of the study was to analyse the disturbances of the oro-pharyngeal swallowing phase of dysphagia in amyotrophic lateral sclerosis (ALS patients with the use of specific manometric measurements and to evaluate their plausible association with the duration of the disease. Seventeen patients with ALS were evaluated with manometric examinations of the oral and pharyngeal part of the gastrointestinal tract. Tests were carried out by using the oesophageal balloon-based method with four balloon transducers located 5 cm away from each other. The following manometric parameters were analysed: the base of tongue contraction (BTC and the upper oesophageal sphincter pressure (UESP, and the hypopharyngeal suction pump (HSP as well as the oro-pharyngeal, pharyngeal and hypopharyngeal transit time and average pharyngeal bolus velocity (oropharyngeal transit time (OTT, pharyngeal transit time (PTT, hypopharyngeal transit time (HTT and average pharyngeal bolus velocity (APBV, respectively. Manomatric examinations during swallowing in patients with ALS showed significant weakness of BTC, a decrease of HSP and a decrease of the velocity of bolus transit inside the pharynx which were particularly marked between the first and the third examination. Manometric examinations of the oro-pharyngeal part of the gastrointestinal tract are useful and supportive methods in the analysis of swallowing disturbances in ALS patients.

Acute Type A Aortic Dissection Successfully Managed with One-stage Surgery of Total Aortic Arch Replacement with Supra-aortic Transposition Plus Frozen Elephant Trunk Technique

Directory of Open Access Journals (Sweden)

Meng-Lin Lee

2014-09-01

Full Text Available Acute type A aortic dissection has long been a challenging issue. The surgical techniques traditionally vary with the anatomic extent of the aortic dissection. Simple ascending aortic grafting can be lifesaving, but the lesions beyond the aorta, which include the arch vessels and descending aorta, remain potential hazards. In this paper, we present a patient in which acute type A aortic dissection with lesions extending into descending thoracic aorta was successfully managed by total arch replacement with supra-aortic transposition plus the frozen elephant trunk technique to the descending aorta. A 67-year-old gentleman presented with severe tearing pain from the anterior to posterior chest. Computed tomography confirmed the diagnosis of acute type A dissection extending to the level of the right common iliac artery. An emergent operation was performed as in the aforementioned technique. The surgery went well and the patient was discharged without comorbidities on postoperative day 25. The patient had regular outpatient clinical follow-up. The follow-up computed tomography images showed adequate results with the obliteration of the false lumen. In conclusion, total aortic arch replacement with supra-aortic transposition plus frozen elephant trunk technique is a safe and feasible operative method for patients with detrimental acute type A aortic dissection.

Aortopathy in Congenital Heart Disease in Adults: Aortic Dilatation with Decreased Aortic Elasticity that Impacts Negatively on Left Ventricular Function.

Science.gov (United States)

Niwa, Koichiro

2013-04-01

Bicuspid aortic valve and/or coarctation of the aorta are consistently associated with ascending aortic and para-coarctation medial abnormalities. Medial abnormalities in the ascending aorta are prevalent in other types of patients with a variety of forms congenital heart disease (CHD), such as single ventricle, persistent truncus arteriosus, transposition of the great arteries, hypoplastic left heart syndrome, tetralogy of Fallot. These abnormalities encompass a wide age range, and may predispose to dilatation, aneurysm, and rupture that necessitates aortic valve and root surgery. This dilatation can develop in CHD patients without stenotic region. These CHDs exhibit ongoing dilatation of the aortic root and reduced aortic elasticity and increased aortic stiffness that may relate to intrinsic properties of the aortic root. The concept of aortic dilatation is shifting a paradigm of aortic dilatation, as so called post stenotic dilatation, to primary intrinsic aortopahy. These aortic dilatation and increased stiffness can induce aortic aneurysm, rupture of the aorta and aortic regurgitation, but also provoke left ventricular hypertrophy, reduced coronary artery flow and left ventricular failure. We can recognize this association of aortic pathophysiological abnormality, aortic dilation and aorto-left ventricular interaction as a new clinical entity: "aortopathy".

Conduction Abnormalities and Permanent Pacemaker Implantation After Transcatheter Aortic Valve Replacement Using the Repositionable LOTUS Device: The United Kingdom Experience.

Science.gov (United States)

Rampat, Rajiv; Khawaja, M Zeeshan; Hilling-Smith, Roland; Byrne, Jonathan; MacCarthy, Philip; Blackman, Daniel J; Krishnamurthy, Arvindra; Gunarathne, Ashan; Kovac, Jan; Banning, Adrian; Kharbanda, Raj; Firoozi, Sami; Brecker, Stephen; Redwood, Simon; Bapat, Vinayak; Mullen, Michael; Aggarwal, Suneil; Manoharan, Ganesh; Spence, Mark S; Khogali, Saib; Dooley, Maureen; Cockburn, James; de Belder, Adam; Trivedi, Uday; Hildick-Smith, David

2017-06-26

The authors report the incidence of pacemaker implantation up to hospital discharge and the factors influencing pacing rate following implantation of the LOTUS bioprosthesis (Boston Scientific, Natick, Massachusetts) in the United Kingdom. Transcatheter aortic valve replacement (TAVR) is associated with a significant need for permanent pacemaker implantation. Pacing rates vary according to the device used. The REPRISE II (Repositionable Percutaneous Replacement of Stenotic Aortic Valve Through Implantation of Lotus Valve System) trial reported a pacing rate of 29% at 30 days after implantation of the LOTUS device. Data were collected retrospectively on 228 patients who had the LOTUS device implanted between March 2013 and February 2015 across 10 centers in the United Kingdom. Twenty-seven patients (12%) had pacemakers implanted pre-procedure and were excluded from the analysis. Patients were aged 81.2 ± 7.7 years; 50.7% were male. The mean pre-procedural QRS duration was 101.7 ± 20.4 ms. More than one-half of the cohort (n = 111, 55%) developed new left bundle branch block (LBBB) following the procedure. Permanent pacemakers were implanted in 64 patients (32%) with a median time to insertion of 3.0 ± 3.4 days. Chief indications for pacing were atrioventricular (AV) block (n = 46, 72%), or LBBB with 1st degree AV block (n = 11, 17%). Amongst those who received a pacemaker following TAVR the pre-procedural electrocardiogram findings included: No conduction disturbance (n = 41, 64%); 1st degree AV block (n = 10, 16%); right bundle branch block (n = 6, 9%) and LBBB (n = 5, 8%). LBBB (but not permanent pacemaker) occurred more frequently in patients who had balloon aortic valvuloplasty before TAVR (odds ratio [OR]: 1.25; p = 0.03). Pre-procedural conduction abnormality (composite of 1st degree AV block, hemiblock, right bundle branch block, LBBB) was independently associated with the need for permanent pacemaker (OR: 2.54; p = 0.048). The absence of

Fate of remnant sinuses of Valsalva in patients with bicuspid and trileaflet valves undergoing aortic valve, ascending aorta, and aortic arch replacement.

Science.gov (United States)

Milewski, Rita Karianna; Habertheuer, Andreas; Bavaria, Joseph E; Siki, Mary; Szeto, Wilson Y; Krause, Eric; Korutla, Varun; Desai, Nimesh D; Vallabhajosyula, Prashanth

2017-08-01

In patients presenting with aortic valvulopathy with concomitant ascending aortic aneurysm, surgical management of the sinus of Valsalva segment remains undefined, especially for moderately dilated aortic roots. In patients with this pathology undergoing aortic valve replacement with supracoronary ascending aorta replacement, we assessed the fate of the remnant preserved sinus of Valsalva segment stratified by aortic valve morphology and pathology. From 2002 to 2015, 428 patients underwent elective aortic valve replacement with supracoronary ascending aorta replacement. Patients were stratified on the basis of valvular morphology (bicuspid aortic valve [n = 254] and tricuspid aortic valve [n = 174]), valvular pathology (bicuspid aortic valve with aortic stenosis [n = 178], bicuspid aortic valve with aortic insufficiency [n = 76], tricuspid aortic valve with aortic stenosis [n = 61], tricuspid aortic valve with aortic insufficiency [n = 113]), and preoperative sinus of Valsalva dimensions (45 mm). Kaplan-Meier analysis revealed no significant difference in freedom from reoperation in tricuspid aortic valve versus bicuspid aortic valve (P = .576). Multivariable Cox regression model performed with sinus of Valsalva dimensions at baseline and follow-up as time-varying covariates did not adversely affect survival. A repeated-measure, mixed-effects model constructed to assess longitudinal sinus of Valsalva trends revealed that the retained sinus of Valsalva dimensions remain stable over long-term follow-up (discharge to ≥10 years), irrespective of valvular morphology/pathology (bicuspid aortic valve with aortic insufficiency, tricuspid aortic valve with aortic insufficiency, tricuspid aortic valve with aortic stenosis) and preoperative sinus of Valsalva groups (45 mm). In patients with nonaneurysmal sinuses of Valsalva undergoing aortic valve replacement with supracoronary ascending aorta replacement, the sinus segment can be preserved irrespective of

Minimally invasive aortic valve replacement

DEFF Research Database (Denmark)

Foghsgaard, Signe; Schmidt, Thomas Andersen; Kjaergard, Henrik K

2009-01-01

In this descriptive prospective study, we evaluate the outcomes of surgery in 98 patients who were scheduled to undergo minimally invasive aortic valve replacement. These patients were compared with a group of 50 patients who underwent scheduled aortic valve replacement through a full sternotomy...... operations were completed as mini-sternotomies, 4 died later of noncardiac causes. The aortic cross-clamp and perfusion times were significantly different across all groups (P replacement...... is an excellent operation in selected patients, but its true advantages over conventional aortic valve replacement (other than a smaller scar) await evaluation by means of randomized clinical trial. The "extended mini-aortic valve replacement" operation, on the other hand, is a risky procedure that should...

A correlative study of aortic valve rotation angle and thoracic aortic sizes using ECG gated CT angiography

Energy Technology Data Exchange (ETDEWEB)

Saremi, Farhood, E-mail: fsaremi@usc.edu; Cen, Steven; Tayari, Nazila; Alizadeh, Houman; Emami, Amir; Lin, Leah; Fleischman, Fernando

2017-04-15

Objective: Various degrees of aortic valve rotation may be seen in individuals with no history of congenital cardiovascular malformations, but its association with aortic sizes has not been studied. Methods: Gated computed tomographic (CT angiograms in 217 patients were studied (66.7 ± 15; 22–97 years old)). Aortic diameters were determined at 5 anatomic locations. The length of the aorta from sinus to left subclavian artery was measured. The angle of valve rotation was recorded by measuring the angle between a line connecting the midpoint of the non-coronary sinus to the anterior commissure and another line along the interatrial septum. Rotation angles were correlated with aortic measurements. Patients were separated into two groups based on aortic sizes and into three groups based on age. The threshold for aortic dilatation was set at maximum ascending aorta diameter ≥40 mm (≥21 mm body surface area [BSA] indexed). Results: No significant difference in rotation angles was seen between the three age groups or between genders. Rotation angles were significantly correlated with maximal, average, and BSA adjustment of the aortic root and ascending aortic measurements. The aortic root angles were significantly different between the dilated versus nondilated aortas. There was no significant association between the rotation angles and age, length of ascending aorta, or diameters of descending aorta. Multivariate adaptive regression splines showed 25° of aortic root rotation as the diagnostic cut off for ascending aorta dilation. Above the 25° rotation, every 10° of increasing rotation was associated with a 3.78 ± 0.87 mm increase in aortic diameter (p < 0.01) and a 1.73 ± 0.25 times increased risk for having a dilated aorta (p < 0.01). Conclusion: Rotation angles of the aortic valve may be an independent non-invasive imaging marker for dilatation of the ascending aorta. Patients with increased rotation angle of the aortic valve may have higher risk for

Analysis of Flight of Near-Space Balloon

Science.gov (United States)

Miller, Zech; Evans, Austin; Seyfert, James; Leadlove, Kyle; Gumina, Kaitlyn; Martell, Eric

2015-04-01

In December 2014, the Electronics class at Millikin University launched a balloon designed to travel into the near-space region of the atmosphere. The balloon was equipped with an instrumentation package including a camera, accelerometer, barometric pressure sensor, temperature probes, as well as a system for tracking using an Automatic Packet Reporting System (APRS). The balloon was launched from Decatur, IL, and landed in Marysville, OH, nearly 320 miles away. The students then analyzed the data from the flight and compared results to expectations.

Heat Transfer Model for Hot Air Balloons

OpenAIRE

Lladó Gambín, Adriana

2016-01-01

A heat transfer model and analysis for hot air balloons is presented in this work, backed with a flow simulation using SolidWorks. The objective is to understand the major heat losses in the balloon and to identify the parameters that affect most its flight performance. Results show that more than 70% of the heat losses are due to the emitted radiation from the balloon envelope and that convection losses represent around 20% of the total. A simulated heating source is also included in the mod...

Accurate Determination of the Volume of an Irregular Helium Balloon

Science.gov (United States)

Blumenthal, Jack; Bradvica, Rafaela; Karl, Katherine

2013-01-01

In a recent paper, Zable described an experiment with a near-spherical balloon filled with impure helium. Measuring the temperature and the pressure inside and outside the balloon, the lift of the balloon, and the mass of the balloon materials, he described how to use the ideal gas laws and Archimedes' principal to compute the average molecular…

Hemodynamic and clinical impact of prosthesis-patient mismatch after transcatheter aortic valve implantation.

Science.gov (United States)

Ewe, See Hooi; Muratori, Manuela; Delgado, Victoria; Pepi, Mauro; Tamborini, Gloria; Fusini, Laura; Klautz, Robert J M; Gripari, Paola; Bax, Jeroen J; Fusari, Melissa; Schalij, Martin J; Marsan, Nina Ajmone

2011-10-25

This study examined the mid-term hemodynamic and clinical impact of prosthesis-patient mismatch (PPM) in patients undergoing transcatheter aortic valve implantation (TAVI) with balloon-expandable valves. PPM can be observed after aortic valve surgery. However, little is known about the incidence of PPM in patients undergoing TAVI. Echocardiography and clinical assessment were performed in 165 patients at baseline, before hospital discharge, and at 6 months after TAVI. PPM was defined as an indexed effective orifice area ≤0.85 cm(2)/m(2). Thirty patients (18.2%) showed PPM before hospital discharge. At baseline, patients with PPM had a larger body surface area (1.84 ± 0.18 m(2) vs. 1.73 ± 0.18 m(2), p = 0.003) and a greater severity of aortic stenosis (indexed valve area 0.35 ± 0.09 cm(2)/m(2) vs. 0.40 ± 0.10 cm(2)/m(2), p = 0.005) than patients without PPM. Patients with PPM demonstrated a slower and smaller reduction in mean transaortic gradient, limited left ventricular (LV) mass regression, and left atrial volume reduction over 6 months compared with patients without PPM. LV filling pressure, measured by E/e', tended to remain elevated in patients with PPM. Importantly, a higher proportion of patients with PPM did not improve in New York Heart Association functional class compared with patients without PPM (36.7% vs. 1.5%, p < 0.001), although major adverse valve-related and cardiovascular events did not differ between the 2 groups. PPM may be observed after TAVI and when present may be accompanied by less favorable changes in transvalvular hemodynamics, limited LV mass regression, persistent elevated LV filling pressure, and less improvement in clinical functional status. Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Imaging techniques in transcatheter aortic valve replacement

Directory of Open Access Journals (Sweden)

Quaife RA

2013-11-01

Full Text Available Robert A Quaife, Jennifer Dorosz, John C Messenger, Ernesto E Salcedo Division of Cardiology, University of Colorado, Aurora, CO, USA Abstract: Calcific aortic stenosis is now understood as a complex valvular degenerative process sharing many risk factors with atherosclerosis. Once patients develop symptomatic calcific aortic stenosis, the only effective treatment is aortic valve replacement. In the past decade, transcatheter aortic valve replacement (TAVR has been developed as an alternative to surgery to treat severe calcific aortic stenosis. Cardiac imaging plays a pivotal role in the contemporary management of patients with calcific aortic stenosis, and particularly in patients being considered for TAVR, who demand detailed imaging of the aortic valve apparatus. In this review, we highlight the role of cardiac imaging for patient selection, procedural guidance, and evaluation of results of TAVR. Keywords: aortic stenosis, cardiovascular imaging, transcutaneous aortic valve replacement

Meshed-Pumpkin Super-Pressure Balloon Design

Science.gov (United States)

Jones, Jack; Yavrouian, Andre

2003-01-01

An improved, lightweight design has been proposed for super-pressure balloons used to carry scientific instruments at high altitudes in the atmosphere of Earth for times as long as 100 days. [A super-pressure balloon is one in which the pressure of the buoyant gas (typically, helium) is kept somewhat above ambient pressure in order to maintain approximately constant density and thereby regulate the altitude.] The proposed design, called "meshed pumpkin," incorporates the basic concept of the pumpkin design, which is so named because of its appearance. The pumpkin design entails less weight than does a spherical design, and the meshed-pumpkin design would reduce weight further. The basic idea of the meshed-pumpkin design is to reinforce the membrane of a pumpkin balloon by attaching a strong, lightweight fabric mesh to its outer surface. The reinforcement would make it possible to reduce the membrane mass to one-third or less of that of the basic pumpkin design while retaining sufficient strength to enable the balloon to remain at approximately constant altitude for months.

Association Between Gout and Aortic Stenosis.

Science.gov (United States)

Chang, Kevin; Yokose, Chio; Tenner, Craig; Oh, Cheongeun; Donnino, Robert; Choy-Shan, Alana; Pike, Virginia C; Shah, Binita D; Lorin, Jeffrey D; Krasnokutsky, Svetlana; Sedlis, Steven P; Pillinger, Michael H

2017-02-01

An independent association between gout and coronary artery disease is well established. The relationship between gout and valvular heart disease, however, is unclear. The aim of this study was to assess the association between gout and aortic stenosis. We performed a retrospective case-control study. Aortic stenosis cases were identified through a review of outpatient transthoracic echocardiography (TTE) reports. Age-matched controls were randomly selected from patients who had undergone TTE and did not have aortic stenosis. Charts were reviewed to identify diagnoses of gout and the earliest dates of gout and aortic stenosis diagnosis. Among 1085 patients who underwent TTE, 112 aortic stenosis cases were identified. Cases and nonaortic stenosis controls (n = 224) were similar in age and cardiovascular comorbidities. A history of gout was present in 21.4% (n = 24) of aortic stenosis subjects compared with 12.5% (n = 28) of controls (unadjusted odds ratio 1.90, 95% confidence interval 1.05-3.48, P = .038). Multivariate analysis retained significance only for gout (adjusted odds ratio 2.08, 95% confidence interval 1.00-4.32, P = .049). Among subjects with aortic stenosis and gout, gout diagnosis preceded aortic stenosis diagnosis by 5.8 ± 1.6 years. The age at onset of aortic stenosis was similar among patients with and without gout (78.7 ± 1.8 vs 75.8 ± 1.0 years old, P = .16). Aortic stenosis patients had a markedly higher prevalence of precedent gout than age-matched controls. Whether gout is a marker of, or a risk factor for, the development of aortic stenosis remains uncertain. Studies investigating the potential role of gout in the pathophysiology of aortic stenosis are warranted and could have therapeutic implications. Published by Elsevier Inc.

Cryo-balloon catheter localization in fluoroscopic images

Science.gov (United States)

Kurzendorfer, Tanja; Brost, Alexander; Jakob, Carolin; Mewes, Philip W.; Bourier, Felix; Koch, Martin; Kurzidim, Klaus; Hornegger, Joachim; Strobel, Norbert

2013-03-01

Minimally invasive catheter ablation has become the preferred treatment option for atrial fibrillation. Although the standard ablation procedure involves ablation points set by radio-frequency catheters, cryo-balloon catheters have even been reported to be more advantageous in certain cases. As electro-anatomical mapping systems do not support cryo-balloon ablation procedures, X-ray guidance is needed. However, current methods to provide support for cryo-balloon catheters in fluoroscopically guided ablation procedures rely heavily on manual user interaction. To improve this, we propose a first method for automatic cryo-balloon catheter localization in fluoroscopic images based on a blob detection algorithm. Our method is evaluated on 24 clinical images from 17 patients. The method successfully detected the cryoballoon in 22 out of 24 images, yielding a success rate of 91.6 %. The successful localization achieved an accuracy of 1.00 mm +/- 0.44 mm. Even though our methods currently fails in 8.4 % of the images available, it still offers a significant improvement over manual methods. Furthermore, detecting a landmark point along the cryo-balloon catheter can be a very important step for additional post-processing operations.

Introduction (Special Issue on Scientific Balloon Capabilities and Instrumentation)

Science.gov (United States)

Gaskin, Jessica A.; Smith, I. S.; Jones, W. V.

2014-01-01

In 1783, the Montgolfier brothers ushered in a new era of transportation and exploration when they used hot air to drive an un-tethered balloon to an altitude of 2 km. Made of sackcloth and held together with cords, this balloon challenged the way we thought about human travel, and it has since evolved into a robust platform for performing novel science and testing new technologies. Today, high-altitude balloons regularly reach altitudes of 40 km, and they can support payloads that weigh more than 3,000 kg. Long-duration balloons can currently support mission durations lasting 55 days, and developing balloon technologies (i.e. Super-Pressure Balloons) are expected to extend that duration to 100 days or longer; competing with satellite payloads. This relatively inexpensive platform supports a broad range of science payloads, spanning multiple disciplines (astrophysics, heliophysics, planetary and earth science.) Applications extending beyond traditional science include testing new technologies for eventual space-based application and stratospheric airships for planetary applications.

Detecting atheromatous plaques in the aortic arch or supra-aortic arteries for more accurate stroke subtype classification.

Science.gov (United States)

Cui, Xiaoyang; Wu, Simiao; Zeng, Quantao; Xiao, Jiahe; Liu, Ming

2015-02-01

To investigate the correlations of atheromatous plaques in the aortic arch or supra-aortic arteries with intracranial arterial stenosis and carotid plaques in stroke patients, and to determine whether taking these plaques into account will reduce the proportion of patients in the undetermined etiology group. We prospectively enrolled 308 ischemic stroke patients, whose clinical characteristics and A-S-C-O classifications were compared with analyses of intracranial arteries, carotid arteries, aortic arch, and supra-aortic arteries. 125(40.6%) patients had plaques in the aortic arch or supra-aortic arteries, of which 106 (84.8%) had complex plaques. No correlations were observed between these plaques and carotid plaques ( p = 0.283) or intracranial arterial stenosis ( p = 0.097). After detecting the mobile thrombi in the aortic arch and supra-aortic arteries, the proportion of patients in the atherothrombosis group was increased from 33.8% to 55.5% ( p = 0.00), whereas the proportion of patients in stroke of undetermined etiology group was decreased from 19.2% to 11.0% ( p = 0.00). Examining only the carotid and intracranial arteries may not provide adequate information about large arteries in stroke patients. Therefore, it would be better to include a search for relevant plaques in the aortic arch or supra-aortic arteries in modern stroke workup, for it may lead to more accurate stroke subtype classification and guide secondary prevention.

The changing course of aortic valve disease in Scotland: temporal trends in hospitalizations and mortality and prognostic importance of aortic stenosis.

Science.gov (United States)

Berry, Colin; Lloyd, Suzanne M; Wang, Yanzhong; Macdonald, Alyson; Ford, Ian

2013-06-01

To investigate the contemporary clinical course of aortic valve disease types. We performed a retrospective population-level epidemiological study of hospitalized care in Scotland from 1 January 1997 to 31 December 2005 using electronic case identification of hospital admissions and deaths. Time-to-event analyses were performed using Cox Proportional-Hazards models. A total of 19 733 adults with an index hospitalization and a final diagnosis of non-congenital aortic valve disease were identified. Aortic stenosis, aortic insufficiency, mixed aortic valve disease, or unspecified aortic valve disease occurred in 13 220 (67.0%), 2807 (14.2%), 699 (3.5%), and 3007 (15.2%), individuals, respectively. The majority of hospitalizations occurred in elderly persons aged 80 and older. In total, 9981 (50.6%) patients had died by 31 December 2006. When compared with aortic stenosis, the risk of death was less with aortic insufficiency [hazard ratio (95% confidence interval) 0.79 (0.74, 0.84)] and mixed aortic valve disease [0.83 (0.74, 0.93)]. Female gender, admission year, and hypertension were associated with lower mortality in patients with aortic stenosis. Patients with aortic stenosis had increased risk of death or heart failure (adjusted P valve replacement of whom 73.2% had aortic stenosis, 11.9% aortic valve disease (unspecified),10.0% aortic insufficiency, and 4.9% aortic stenosis with insufficiency. Patients with aortic stenosis with insufficiency had increased likelihood of aortic valve replacement [1.19 (1.02, 1.38)]. Age, female gender, and co-morbidity reduced the likelihood of aortic valve replacement. The incidence of aortic valve stenosis has substantially increased in Scotland in recent years. Aortic stenosis predicts morbidity and mortality when compared with other types of aortic valve disease.

Looners: Inside the world of balloon fetishism

OpenAIRE

McIntyre, Karen E

2011-01-01

In the spring of 1997, Shaun had just broken up with a boyfriend, and his roommate had moved out. Living alone for the first time and relieved of the fear that someone might walk in the door, he was finally able to indulge his fantasy. The young man sat on his couch and started blowing up balloons. Shaun had loved playing with balloons since he was a child. When he hit puberty, he felt his first orgasm rubbing against a balloon. It was then that his relationship with the object took ...

Taking the Hot Air Out of Balloons.

Science.gov (United States)

Brinks, Virgil L.; Brinks, Robyn L.

1994-01-01

Describes how a teacher can give their students the challenge of designing and building model balloons or blimps. The project helps students learn the basics of balloon flight and what it really means to be "lighter than air." (PR)

Aortic Blood Flow Reversal Determines Renal Function: Potential Explanation for Renal Dysfunction Caused by Aortic Stiffening in Hypertension.

Science.gov (United States)

Hashimoto, Junichiro; Ito, Sadayoshi

2015-07-01

Aortic stiffness determines the glomerular filtration rate (GFR) and predicts the progressive decline of the GFR. However, the underlying pathophysiological mechanism remains obscure. Recent evidence has shown a close link between aortic stiffness and the bidirectional (systolic forward and early diastolic reverse) flow characteristics. We hypothesized that the aortic stiffening-induced renal dysfunction is attributable to altered central flow dynamics. In 222 patients with hypertension, Doppler velocity waveforms were recorded at the proximal descending aorta to calculate the reverse/forward flow ratio. Tonometric waveforms were recorded to measure the carotid-femoral (aortic) and carotid-radial (peripheral) pulse wave velocities, to estimate the aortic pressure from the radial waveforms, and to compute the aortic characteristic impedance. In addition, renal hemodynamics was evaluated by duplex ultrasound. The estimated GFR was inversely correlated with the aortic pulse wave velocity, reverse/forward flow ratio, pulse pressure, and characteristic impedance, whereas it was not correlated with the peripheral pulse wave velocity or mean arterial pressure. The association between aortic pulse wave velocity and estimated GFR was independent of age, diabetes mellitus, hypercholesterolemia, and antihypertensive medication. However, further adjustment for the aortic reverse/forward flow ratio and pulse pressure substantially weakened this association, and instead, the reverse/forward flow ratio emerged as the strongest determinant of estimated GFR (P=0.001). A higher aortic reverse/forward flow ratio was also associated with lower intrarenal forward flow velocities. These results suggest that an increase in aortic flow reversal (ie, retrograde flow from the descending thoracic aorta toward the aortic arch), caused by aortic stiffening and impedance mismatch, reduces antegrade flow into the kidney and thereby deteriorates renal function. © 2015 American Heart Association

Paraplegia following intraaortic balloon circulatory assistance

Directory of Open Access Journals (Sweden)

Benício Anderson

1999-01-01

Full Text Available Intraaortic balloon counterpulsation is frequently used in patients experiencing severe ventricular dysfunction following maximal drug therapy. However, even with the improvement of percutaneous insertion techniques, the procedure has always been followed by vascular, infectious, and neurological complications. This article describes a case of paraplegia due to intraaortic balloon counterpulsation in the postoperative period of cardiac surgery.

A New Look at Risk-Taking: Using a Translational Approach to Examine Risk-Taking Behavior on the Balloon Analogue Risk Task

OpenAIRE

DeMartini, Kelly S.; Leeman, Robert F.; Corbin, William R.; Toll, Benjamin A.; Fucito, Lisa M.; Lejuez, Carl W.; O’Malley, Stephanie S.

2014-01-01

Models of risk-taking typically assume that the variability of outcomes is important in the likelihood of making a risky choice. In an animal model of the Balloon Analogue Risk Task (BART), within-session variability, or the coefficient of variability (CV), was found to be a novel predictor of behavior (Jentsch et al., 2010). Human studies have not investigated how BART performance differs when using the CV versus a traditional BART measure (e.g. number of pumps). This study sought to determi...

Extended aortic repair using frozen elephant trunk technique for Marfan syndrome with acute aortic dissection.

Science.gov (United States)

Uchida, Naomichi; Katayama, Akira; Kuraoka, Masatsugu; Katayama, Keijiro; Takahashi, Shinya; Takasaki, Taiichi; Sueda, Taijiro

2013-01-01

The aim of this study was to analyze midterm results of frozen elephant trunk technique for Marfan syndrome with acute aortic dissection. Between February 1999 and August 2011 we performed arch replacement uisng frozen elephant trunk technique for acute aortic dissection in 8 patients with Marfan syndrome containing two complicated type B dissections and six type A dissections.Five patients compromised annulo-aortic ectasia who performed Bentall operation. No patients died in the initial operation. Fate of false lumen on the stent graft border was expressed by CT scan follow-up that were patent in 0, thrombosis in 5 and absorption in 3 patients. One patient who had new aortic dissection 8 years after initial surgery required the Crawford V operation. Ten-years-survival rate was 100% and ten years-event free rate was 67%. Frozen elephant trunk technique was feasible for Marfan syndrome with acute aortic dissection and might become alternative prophylactic treatment to the downstream aorta for acute aortic dissection.

Effect of personalized external aortic root support on aortic root motion and distension in Marfan syndrome patients.

Science.gov (United States)

Izgi, Cemil; Nyktari, Evangelia; Alpendurada, Francisco; Bruengger, Annina Studer; Pepper, John; Treasure, Tom; Mohiaddin, Raad

2015-10-15

Personalized external aortic root support (PEARS) is a novel surgical approach with the aim of stabilizing the aortic root size and decreasing risk of dissection in Marfan syndrome patients. A bespoke polymer mesh tailored to each patient's individual aorta shape is produced by modeling and then surgically implanted. The aim of this study is to assess the mechanical effects of PEARS on the aortic root systolic downward motion (an important determinant of aortic wall stress), aortic root distension and on the left ventricle (LV). A cohort of 27 Marfan patients had a prophylactic PEARS surgery between 2004 and 2012 with 24 having preoperative and follow-up cardiovascular magnetic resonance imaging studies. Systolic downward aortic root motion, aortic root distension, LV volumes/mass and mitral annular systolic excursion before the operation and in the latest follow-up were measured randomly and blinded. After a median follow-up of 50.5 (IQR 25.5-72) months following implantation of PEARS, systolic downward motion of aortic root was significantly decreased (12.6±3.6mm pre-operation vs 7.9±2.9mm latest follow-up, p<0.00001). There was a tendency for a decrease in systolic aortic root distension but this was not significant (median 4.5% vs 2%, p=0.35). There was no significant change in LV volumes, ejection fraction, mass and mitral annular systolic excursion in follow-up. PEARS surgery decreases systolic downward aortic root motion which is an important determinant of longitudinal aortic wall stress. Aortic wall distension and Windkessel function are not significantly impaired in the follow-up after implantation of the mesh which is also supported by the lack of deterioration of LV volumes or mass. Crown Copyright © 2015. Published by Elsevier Ireland Ltd. All rights reserved.

Deflation of gastric band balloon in pregnancy for improving outcomes.

Science.gov (United States)

Jefferys, Amanda E; Siassakos, Dimitrios; Draycott, Tim; Akande, Valentine A; Fox, Robert

2013-04-30

In line with the rise in the prevalence of obesity, an increasing number of women of childbearing age are undergoing laparoscopic adjustable gastric banding (LAGB), resulting in an increasing number of pregnancies with a band in place. Currently, there is no consensus on optimal band management in pregnancy. Some clinicians advocate leaving the band balloon inflated to reduce gestational weight gain and associated adverse perinatal outcomes. However, there are concerns that maintaining balloon inflation during pregnancy might increase the risk of band complications and adversely affect fetal development and/or growth as a result of reduced nutritional intake. To compare maternal and perinatal outcomes for elective gastric band balloon deflation versus intention to maintain balloon inflation during pregnancy. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 September 2012) and the Web of Science database (1940 to September 2012). Randomised-controlled trials comparing elective deflation of the gastric band balloon with intention to maintain balloon inflation in pregnant women who have undergone LAGB. Two review authors independently assessed studies for inclusion. No studies met the criteria for inclusion in the review. To date no randomised controlled trials exist that compare elective deflation of the gastric band balloon in pregnancy versus intention to maintain balloon inflation. Further research is needed to define the optimum management of the gastric band balloon in pregnancy.

Bovine aortic arch with supravalvular aortic stenosis.

Science.gov (United States)

Idhrees, Mohammed; Cherian, Vijay Thomas; Menon, Sabarinath; Mathew, Thomas; Dharan, Baiju S; Jayakumar, K

2016-09-01

A 5-year-old boy was diagnosed to have supravalvular aortic stenosis (SVAS). On evaluation of CT angiogram, there was associated bovine aortic arch (BAA). Association of BAA with SVAS has not been previously reported in literature, and to best of our knowledge, this is the first case report of SVAS with BAA. Recent studies show BAA as a marker for aortopathy. SVAS is also an arteriopathy. In light of this, SVAS can also possibly be a manifestation of aortopathy associated with BAA. Copyright © 2015 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

Reduction of prostate intrafraction motion using gas-release rectal balloons

International Nuclear Information System (INIS)

Su Zhong; Zhao Tianyu; Li Zuofeng; Hoppe, Brad; Henderson, Randy; Mendenhall, William; Nichols, R. Charles; Marcus, Robert; Mendenhall, Nancy

2012-01-01

Purpose: To analyze prostate intrafraction motion using both non-gas-release (NGR) and gas-release (GR) rectal balloons and to evaluate the ability of GR rectal balloons to reduce prostate intrafraction motion. Methods: Twenty-nine patients with NGR rectal balloons and 29 patients with GR balloons were randomly selected from prostate patients treated with proton therapy at University of Florida Proton Therapy Institute (Jacksonville, FL). Their pretreatment and post-treatment orthogonal radiographs were analyzed, and both pretreatment setup residual error and intrafraction-motion data were obtained. Population histograms of intrafraction motion were plotted for both types of balloons. Population planning target-volume (PTV) margins were calculated with the van Herk formula of 2.5Σ+ 0.7σ to account for setup residual errors and intrafraction motion errors. Results: Pretreatment and post-treatment radiographs indicated that the use of gas-release rectal balloons reduced prostate intrafraction motion along superior–inferior (SI) and anterior–posterior (AP) directions. Similar patient setup residual errors were exhibited for both types of balloons. Gas-release rectal balloons resulted in PTV margin reductions from 3.9 to 2.8 mm in the SI direction, 3.1 to 1.8 mm in the AP direction, and an increase from 1.9 to 2.1 mm in the left–right direction. Conclusions: Prostate intrafraction motion is an important uncertainty source in radiotherapy after image-guided patient setup with online corrections. Compared to non-gas-release rectal balloons, gas-release balloons can reduce prostate intrafraction motion in the SI and AP directions caused by gas buildup.

Reduction of prostate intrafraction motion using gas-release rectal balloons

Energy Technology Data Exchange (ETDEWEB)

Su Zhong; Zhao Tianyu; Li Zuofeng; Hoppe, Brad; Henderson, Randy; Mendenhall, William; Nichols, R. Charles; Marcus, Robert; Mendenhall, Nancy [Department of Radiation Oncology, University of Florida Proton Therapy Institute, Jacksonville, Florida 32206 (United States)

2012-10-15

Purpose: To analyze prostate intrafraction motion using both non-gas-release (NGR) and gas-release (GR) rectal balloons and to evaluate the ability of GR rectal balloons to reduce prostate intrafraction motion. Methods: Twenty-nine patients with NGR rectal balloons and 29 patients with GR balloons were randomly selected from prostate patients treated with proton therapy at University of Florida Proton Therapy Institute (Jacksonville, FL). Their pretreatment and post-treatment orthogonal radiographs were analyzed, and both pretreatment setup residual error and intrafraction-motion data were obtained. Population histograms of intrafraction motion were plotted for both types of balloons. Population planning target-volume (PTV) margins were calculated with the van Herk formula of 2.5{Sigma}+ 0.7{sigma} to account for setup residual errors and intrafraction motion errors. Results: Pretreatment and post-treatment radiographs indicated that the use of gas-release rectal balloons reduced prostate intrafraction motion along superior-inferior (SI) and anterior-posterior (AP) directions. Similar patient setup residual errors were exhibited for both types of balloons. Gas-release rectal balloons resulted in PTV margin reductions from 3.9 to 2.8 mm in the SI direction, 3.1 to 1.8 mm in the AP direction, and an increase from 1.9 to 2.1 mm in the left-right direction. Conclusions: Prostate intrafraction motion is an important uncertainty source in radiotherapy after image-guided patient setup with online corrections. Compared to non-gas-release rectal balloons, gas-release balloons can reduce prostate intrafraction motion in the SI and AP directions caused by gas buildup.

New concepts for interplanetary balloons and blimps, particularly for Titan

Science.gov (United States)

Nott, J.

This paper proposes novel approaches for balloons for planets Titan BALLUTE A balloon or blimp arriving at a planet or moon with an atmosphere might inflate falling under a parachute or after landing Neither is ideal In both cases the envelope must include qualities needed for inflation as well as those for flight A ballute BALLoon parachUTE could be used thus a ballute is like a hot air balloon with a large mouth Initially it fills by ram pressure descending through an atmosphere As proposed it would then be heated by solid propellant It would stop descending and float level with hot air lift It is now a perfect location for inflation without wind or movement through the atmosphere and away from the uncertainties of the surface A ballute could be used over several bodies in the solar system BALLOONS FOR LOW TEMPERATURES Flight in very low temperatures is also discussed Conditions are so different that it is useful to examine basic factors These apply for any planet with low temperature and weather calm enough for balloons or blimps First for terrestrial hot air balloons thermal radiation is usually the dominant way heat is lost But radiation rises with the 4th power of absolute temperature At Titan radiation will be one or two orders of magnitude smaller Also the dense atmosphere allows small balloons small temperature differences So convection is small It appears a hot air balloon can easily be heated by a radioactive source likely carried to make electricity Pinholes are not important in such a balloon

De novo aortic insufficiency during long-term support on a left ventricular assist device: a systematic review and meta-analysis.

Science.gov (United States)

Deo, Salil V; Sharma, Vikas; Cho, Yang Hyun; Shah, Ishan K; Park, Soon J

2014-01-01

Aortic insufficiency (AI) may occur while supported on a left ventricular assist device (LVAD). We conducted a systematic review to determine the incidence, predictors, and consequences of AI during LVAD support. MEDLINE was searched for original studies presenting clinical data regarding patients who developed AI during LVAD implant. Seven observational studies (657 patients) were selected for review; 65% of patients underwent implantation with a continuous-flow device (Cf-LVAD). The incidence of AI was 25% (11-42%) (Support period: 412 ± 281 days). AI increased by 4% (1-6%) per month of support (p < 0.01). AI-positive patients were older at implant (weighted mean difference, 7.7 [4.3; 11.1]; p < 0.01). Female sex (0.002 ± 0.001; p = 0.01) and smaller body surface area (-0.003 ± 0.001 per m; p < 0.01) correlated with progressive AI. Destination therapy patients (odds ratio [OR], 5.3 [1.2, 24]; p = 0.02) and those with Cf-LVAD pumps were likely to develop AI (hazard ratio [HR], 2.2 [1.2, 3.8]; p < 0.01). A closed aortic valve was associated with AI (OR, 4.7 [1.9, 11.8]; p < 0.01). Survival was comparable in both cohorts (HR, 1.5 [0.81, 2.8]; p = 0.2). A significant number of patients develop de novo AI during LVAD support. Advanced age, longer support duration, continuous-flow pumps, and a closed aortic valve are associated with AI. Large cohort studies would improve our understanding of this condition.

Progression and Prognosis of Paravalvular Regurgitation After Transcatheter Aortic Valve Implantation

Directory of Open Access Journals (Sweden)

Rafael Alexandre Meneguz-Moreno

2017-11-01

Full Text Available Abstract Background: The impact of paravalvular regurgitation (PVR following transcatheter aortic valve implantation (TAVI remains uncertain. Objective: To evaluate the impact of PVR on mortality and hospital readmission one year after TAVI. Methods: Between January 2009 and June 2015, a total of 251 patients underwent TAVI with three different prostheses at two cardiology centers. Patients were assessed according to PVR severity after the procedure. Results: PVR was classified as absent/trace or mild in 92.0% (n = 242 and moderate/severe in 7.1% (n = 18. The moderate/severe PVR group showed higher levels of aortic calcification (22% vs. 6%, p = 0.03, higher serum creatinine (1.5 ± 0.7 vs. 1.2 ± 0.4 mg/dL, p = 0.014, lower aortic valve area (0.6 ± 0.1 vs. 0.7 ± 0.2 cm2, p = 0.05, and lower left ventricular ejection fraction (49.2 ± 14.8% vs. 58.8 ± 12.1%, p = 0.009. Patients with moderate/severe PVR had more need for post-dilatation (p = 0.025 and use of larger-diameter balloons (p = 0.043. At one year, all-cause mortality was similar in both groups (16.7% vs. 12%, p = 0.08, as well as rehospitalization (11.1% vs. 7.3%, p = 0.915. PVR grade significantly reduced throughout the first year after the procedure (p < 0.01. The presence of moderate/severe PVR was not associated with higher one-year mortality rates (HR: 0.76, 95% CI: 0.27-2.13, p = 0.864, rehospitalization (HR: 1.08, 95% CI: 0.25-4.69, p=0.915, or composite outcome (HR: 0.77, 95% CI: 0.28-2.13, p = 0.613. Conclusion: In this sample, moderate/severe PVR was not a predictor of long-term mortality or rehospitalization. (Arq Bras Cardiol. 2017; [online].ahead print, PP.0-0

Ballooning modes or Fourier modes in a toroidal plasma?

International Nuclear Information System (INIS)

Connor, J.W.; Taylor, J.B.

1987-01-01

The relationship between two different descriptions of eigenmodes in a torus is investigated. In one the eigenmodes are similar to Fourier modes in a cylinder and are highly localized near a particular rational surface. In the other they are the so-called ballooning modes that extend over many rational surfaces. Using a model that represents both drift waves and resistive interchanges the transition from one of these structures to the other is investigated. In this simplified model the transition depends on a single parameter which embodies the competition between toroidal coupling of Fourier modes (which enhances ballooning) and variation in frequency of Fourier modes from one rational surface to another (which diminishes ballooning). As the coupling is increased each Fourier mode acquires a sideband on an adjacent rational surface and these sidebands then expand across the radius to form the extended mode described by the conventional ballooning mode approximation. This analysis shows that the ballooning approximation is appropriate for drift waves in a tokamak but not for resistive interchanges in a pinch. In the latter the conventional ballooning effect is negligible but they may nevertheless show a ballooning feature. This is localized near the same rational surface as the primary Fourier mode and so does not lead to a radially extended structure

Hybrid aortic repair with antegrade supra-aortic and renovisceral debranching from ascending aorta.

Science.gov (United States)

Del Castro-Madrazo, José Antonio; Rivas-Domínguez, Margarita; Fernández-Prendes, Carlota; Zanabili Al-Sibbai, Amer; Llaneza-Coto, José Manuel; Alonso-Pérez, Manuel

2017-05-01

Aortic dissection is a life threatening condition. Hybrid repair has been described for the treatment of complex aortic pathology such as thoracoabdominal aortic aneurysms (TAAA) and type A and B dissections, although open and total endovascular repair are also possible. Open surgery is still associated with substantial perioperative morbi-mortality rates, thus less invasive techniques such as endovascular repair and hybrid procedures can achieve good results in centers with experience. We present the case of a patient with a chronic type B dissection and TAAA degeneration that was treated in a single stage hybrid procedure with antegrade supra-aortic and renovisceral debranching from the ascending aorta and TEVAR. At three-year follow up, the patient is free of intervention-related complications.

Aviation investigation report : hard landing : fuel leak and fire[Sundance Balloons International Firefly 12B (hot air balloon) C-FNVM, Winnipeg, Manitoba, 15 nm NE, 11 August 2007

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-08-15

This investigation report discussed an incident in Winnipeg in which a hot air balloon attempting to land during strong winds was dragged on its side for approximately 700 feet. The balloon's burners struck the ground as the balloon came to a stop, after which a propane leak occurred. An intense, uncontrolled fire ensued as balloon passengers were exiting from the partially-inverted basket. The pilot and 2 passengers suffered serious injuries, while another 4 passengers suffered minor injuries. The balloon's 2 propane tanks and a fire extinguisher canister exploded during the fire, which destroyed the balloon's basket. The rigging of the balloon was examined and no failures were discovered. Pressure tests showed that the balloon's hoses started leaking at the crimped sleeve fittings at 150 psi. While the pilot had been informed of potentially heavy winds and thunderstorms, changes in wind speed and direction occurred earlier than the forecasted time of 10:00. It was concluded that standards are needed to ensure balloon cabin safety. Balloon operators do not currently require the use of protective helmets or gloves in case of dragged landings. A review will be conducted to address the issue of proposed emergency fuel shut-offs for balloons carrying fare-paying passengers. 2 figs.

Balloon dilatation of iatrogenic urethral strictures

International Nuclear Information System (INIS)

Acunas, B.; Acunas, G.; Gokmen, E.; Celik, L.

1988-01-01

Balloon dilatation of the urethra was performed in five patients with iatrogenic urethral strictures. The urethral strictures were successfully negotiated and dilated in all patients. Redilatation became necessary in a period ranging from 3 to 10 months. The authors believe that balloon dilatation of the urethra can be safely and successfully performed; the procedure produces minimal trauma and immediate relief of symptoms. (orig.)

Balloon catheter dilation of benign esophageal stenosis in children

International Nuclear Information System (INIS)

Fan Guoping; Yu Juming; Zhong Weixing; Zhu Ming; Wu Yeming; Shi Chengren

2001-01-01

Objective: To evaluate the methods and effect of balloon catheter dilation of benign esophageal stenosis in children. Methods: 9 cases had an anastomotic stenosis after surgical correction of esophageal atresia; 11 cases of esophageal stenosis due to ingestion of caustics; one case had an lower esophageal stenosis after Nissen surgery and one case after gastro-esophagoplasty. Age ranged from 17 days to 7 years. Each case had a barium esophagram before balloon dilation. The balloon size varied from 3 to 10 mm in diameter. Results: 21 cases were successful after dilation of balloon catheter. There were no esophageal perforation and complications. The satisfactory results maintained from six months to thirty months. Conclusions: Balloon catheter dilation is a simple, safe and reliable method for the treatment of benign esophageal strictures in children as the first choice

Aortic Disease in the Young: Genetic Aneurysm Syndromes, Connective Tissue Disorders, and Familial Aortic Aneurysms and Dissections

Directory of Open Access Journals (Sweden)

Marcelo Cury

2013-01-01

Full Text Available There are many genetic syndromes associated with the aortic aneurysmal disease which include Marfan syndrome (MFS, Ehlers-Danlos syndrome (EDS, Loeys-Dietz syndrome (LDS, familial thoracic aortic aneurysms and dissections (TAAD, bicuspid aortic valve disease (BAV, and autosomal dominant polycystic kidney disease (ADPKD. In the absence of familial history and other clinical findings, the proportion of thoracic and abdominal aortic aneurysms and dissections resulting from a genetic predisposition is still unknown. In this study, we propose the review of the current genetic knowledge in the aortic disease, observing, in the results that the causative genes and molecular pathways involved in the pathophysiology of aortic aneurysm disease remain undiscovered and continue to be an area of intensive research.

Factors associated with the development of aortic valve regurgitation over time after two different techniques of valve-sparing aortic root surgery.

Science.gov (United States)

Hanke, Thorsten; Charitos, Efstratios I; Stierle, Ulrich; Robinson, Derek; Gorski, Armin; Sievers, Hans-H; Misfeld, Martin

2009-02-01

Early results after aortic valve-sparing root reconstruction are excellent. Longer-term follow-up, especially with regard to aortic valve function, is required for further judgment of these techniques. Between July of 1993 and September of 2006, 108 consecutive patients (mean age 53.0 +/- 15.8 years) underwent the Yacoub operation (group Y) and 83 patients underwent the David operation (group D). Innovative multilevel hierarchic modeling methods were used to analyze aortic regurgitation over time. In general, aortic regurgitation increased with time in both groups. Factors associated with the development of a significant increase in aortic regurgitation were Marfan syndrome, concomitant cusp intervention, and preoperative aortic anulus dimension. In Marfan syndrome, the initial aortic regurgitation was higher in group Y versus group D (0.56 aortic regurgitation vs 0.29 aortic regurgitation, P = .049), whereas the mean annual progression rate of aortic regurgitation was marginally higher in group Y (0.132 aortic regurgitation vs 0.075 aortic regurgitation, P = .1). Concomitant cusp intervention was associated with a significant aortic regurgitation increase in both groups (P Marfan syndrome and a large preoperative aortic annulus diameter were better treated with the reimplantation technique, whereas those with a smaller diameter were better treated with the remodeling technique. Concomitant free-edge plication of prolapsing cusps was disadvantageous in both groups. Considering these factors may serve to improve the aortic valve longevity after valve-sparing aortic root surgery.

Static and quasi-static analysis of lobed-pumpkin balloon

Science.gov (United States)

Nakashino, Kyoichi; Sasaki, Makoto; Hashimoto, Satoshi; Saito, Yoshitaka; Izutsu, Naoki

The present study is motivated by the need to improve design methodology for super pressure balloon with 3D gore design concept, currently being developed at the Scientific Balloon Center of ISAS/JAXA. The distinctive feature of the 3-D gore design is that the balloon film has excess materials not only in the circumferential direction but also in the meridional direction; the meridional excess is gained by attaching the film boundaries to the corresponding tendons of a shorter length with a controlled shortening rate. The resulting balloon shape is a pumpkin-like shape with large bulges formed between adjacent tendons. The balloon film, when fully inflated, develops wrinkles in the circumferential direction over its entire region, so that the stresses in the film are limited to a small amount of uniaxial tension in the circumferential direction while the high meridional loads are carried by re-enforced tendons. Naturally, the amount of wrinkling in the film is dominated by the shortening rate between the film boundaries and the tendon curve. In the 3-D gore design, as a consequence, the shortening rate becomes a fundamental design parameter along with the geometric parameters of the gore. In view of this, we have carried out a series of numerical study of the lobed-pumpkin balloon with varying gore geometry as well as with varying shortening rate. The numerical simula-tions were carried out with a nonlinear finite element code incorporating the wrinkling effect. Numerical results show that there is a threshold value for the shortening rate beyond which the stresses in the balloon film increases disproportionately. We have also carried out quasi-static simulations of the inflation process of the lobed-pumpkin balloon, and have obtained asymmetric deformations when the balloon films are in uniaxial tension state.

Percutaneous closure of a large aortic paravalvular leak using two duct occluder devices

Directory of Open Access Journals (Sweden)

Navaneetha Sasikumar

2013-05-01

Full Text Available A 21-year-old male presented with severe aortic paravalvular leak. He had undergone three cardiac surgeries and also had chronic kidney disease. It was decided for a trans-catheter closure owing to the risks of a fourth surgery and co-morbidity. The device was sized based on angiogram, balloon sizing and two dimensional transesophageal echo. There was significant residual leak after deployment of first device. Hence the defect was re-crossed and two duct occluder devices were positioned across the leak from two arterial access. After confirming position and satisfactory reduction in paravalvular leak, the devices were released in tandem. There was near abolition of leak. The patient is asymptomatic at three months follow up. Larger paravalvular leaks are better addressed with two devices of smaller size rather than a single large device. Technical considerations while deploying multiple devices are discussed.

Aortic valve surgery - open

Science.gov (United States)

... gov/ency/article/007408.htm Aortic valve surgery - open To use the sharing features on this page, ... separates the heart and aorta. The aortic valve opens so blood can flow out. It then closes ...

An Overview of Current and Future Stratospheric Balloon Mission Capabilities

Science.gov (United States)

Smith, Michael

The modern stratospheric balloon has been used for a variety of missions since the late 1940's. Capabilities of these vehicles to carry larger payloads, fly to higher altitudes, and fly for longer periods of time have increased dramatically over this time. In addition to these basic performance metrics, reliability statistics for balloons have reached unprecedented levels in recent years. Balloon technology developed in the United States in the last decade has the potential to open a new era in economical space science using balloons. As always, the advantage of the balloon platform is the fact that missions can be carried out at a fraction of the cost and schedule of orbital missions. A secondary advantage is the fact that instruments can be re-flown numerous times while upgrading sensor and data processing technologies from year to year. New mission capabilities now have the potential for enabling ground breaking observations using balloons as the primary platform as opposed to a stepping stone to eventual orbital observatories. The limit of very high altitude balloon missions will be explored with respect to the current state of the art of balloon materials and fabrication. The same technological enablers will also be applied to possibilities for long duration missions at mid latitudes with payloads of several tons. The balloon types and their corresponding mission profiles will be presented in a performance matrix that will be useful for potential scientific users in planning future research programs.

An analysis of the deployment of a pumpkin balloon at Mars

Science.gov (United States)

Rand, J. L.; Phillips, M. L.

2004-01-01

The design of large superpressure balloons has received significant attention in recent years due to the successful demonstration of various enabling technologies and materials. Of particular note is the "pumpkin" shaped balloon concept, which allows the stress in the envelope to be limited by the surface geometry. Unlike a sphere, where the radius used to determine the stress is determined by the volume of the balloon, the pumpkin utilizes a system of meridional tendons to react the loading in one direction, and form a number of lobes, which limit the stress in the circumferential direction. A suitable superpressure balloon has been designed using this technology which will carry 2 kg in the atmosphere of Mars. The deployment of this balloon is assumed to occur while falling on a decelerator suitably designed for the Mars atmosphere. The inflation is accomplished by a 10 kg system suspended at the nadir of the balloon. As the system falls toward the surface of the planet, helium gas is transferred into the balloon, forming a partially inflated system very similar to an ascending zero pressure balloon. This analysis incorporates the flow of the planetary gas around the inflating balloon which alters the pressure distribution and shape. As a result, stresses are seen to increase beyond the design values which will require the balloon to be redesigned to accommodate this type of dynamic deployment.

Aortic valve replacement and prosthesis-patient mismatch in the era of trans-catheter aortic valve implantation.

Science.gov (United States)

Morita, Shigeki

2016-08-01

The treatment strategy for aortic stenosis (AS) has been changing due to newly developed valvular prostheses and trans-catheter aortic valve implantation (TAVI). To determine the role of new modalities for AS with a small aortic root, papers using the concept of prosthesis-patient mismatch (PPM) were reviewed. First, to determine the cut-off value of the indexed effective orifice area (IEOA) for defining PPM, the studies of surgical aortic valve replacement (SAVR) with a follow-up longer than 5 years and a patient number larger than 500 were reviewed. Second, the papers comparing TAVI and SAVR were reviewed. Furthermore, the prevalence of PPM was reviewed, with the addition of papers on aortic root enlargement, sutureless AVR, and aortic valve reconstruction with autologous pericardium. The results of the long-term survival after aortic valve replacement (AVR) have indicated that an IEOA less than 0.65 cm(2)/m(2) should be avoided in all cases, whereas the indications for patients with an IEOA between 065 and 0.85 cm(2)/m(2) should be determined by considering multiple factors. A large body size and younger age have a significantly negative influence on the long-term survival. In Asian population, the prevalence of PPM was low, despite the fact that the size of the aortic annulus was small. The IEOA after TAVI was larger than after surgical AVR in population-matched studies. To evaluate the role of TAVI and other modalities for a small aortic root, studies with a longer follow-up and larger volume are thus warranted.

Thoracic aortic aneurysms and dissections: endovascular treatment.

Science.gov (United States)

Baril, Donald T; Cho, Jae S; Chaer, Rabih A; Makaroun, Michel S

2010-01-01

The treatment of thoracic aortic disease has changed radically with the advances made in endovascular therapy since the concept of thoracic endovascular aortic repair was first described 15 years ago. Currently, there is a diverse array of endografts that are commercially available to treat the thoracic aorta. Multiple studies, including industry-sponsored and single-institution reports, have demonstrated excellent outcomes of thoracic endovascular aortic repair for the treatment of thoracic aortic aneurysms, with less reported perioperative morbidity and mortality in comparison with conventional open repair. Additionally, similar outcomes have been demonstrated for the treatment of type B dissections. However, the technology remains relatively novel, and larger studies with longer term outcomes are necessary to more fully evaluate the role of endovascular therapy for the treatment of thoracic aortic disease. This review examines the currently available thoracic endografts, preoperative planning for thoracic endovascular aortic repair, and outcomes of thoracic endovascular aortic repair for the treatment of both thoracic aortic aneurysms and type B aortic dissections. Mt Sinai J Med 77:256-269, 2010. (c) 2010 Mount Sinai School of Medicine.

Validated Computational Model to Compute Re-apposition Pressures for Treating Type-B Aortic Dissections

Directory of Open Access Journals (Sweden)

Aashish Ahuja

2018-05-01

Full Text Available The use of endovascular treatment in the thoracic aorta has revolutionized the clinical approach for treating Stanford type B aortic dissection. The endograft procedure is a minimally invasive alternative to traditional surgery for the management of complicated type-B patients. The endograft is first deployed to exclude the proximal entry tear to redirect blood flow toward the true lumen and then a stent graft is used to push the intimal flap against the false lumen (FL wall such that the aorta is reconstituted by sealing the FL. Although endovascular treatment has reduced the mortality rate in patients compared to those undergoing surgical repair, more than 30% of patients who were initially successfully treated require a new endovascular or surgical intervention in the aortic segments distal to the endograft. One reason for failure of the repair is persistent FL perfusion from distal entry tears. This creates a patent FL channel which can be associated with FL growth. Thus, it is necessary to develop stents that can promote full re-apposition of the flap leading to complete closure of the FL. In the current study, we determine the radial pressures required to re-appose the mid and distal ends of a dissected porcine thoracic aorta using a balloon catheter under static inflation pressure. The same analysis is simulated using finite element analysis (FEA models by incorporating the hyperelastic properties of porcine aortic tissues. It is shown that the FEA models capture the change in the radial pressures required to re-appose the intimal flap as a function of pressure. The predictions from the simulation models match closely the results from the bench experiments. The use of validated computational models can support development of better stents by calculating the proper radial pressures required for complete re-apposition of the intimal flap.

False coronary dissection with the new Monorail angioplasty balloon catheter.

Science.gov (United States)

Esplugas, E; Cequier, A R; Sabaté, X; Jara, F

1990-01-01

During percutaneous transluminal coronary angioplasty, the appearance of persistent staining in the vessel by contrast media suggests coronary dissection. We report seven patients in whom a false image of severe coronary dissection was observed during angioplasty performed with the new Monorail balloon catheter. This image emerges at the moment of balloon inflation, is distally located to the balloon, and disappears with balloon catheter deflation. No complications were associated with the appearance of this image.

Aortic valve function after bicuspidization of the unicuspid aortic valve.

Science.gov (United States)

Aicher, Diana; Bewarder, Moritz; Kindermann, Michael; Abdul-Khalique, Hashim; Schäfers, Hans-Joachim

2013-05-01

Unicuspid aortic valve (UAV) anatomy leads to dysfunction of the valve in young individuals. We introduced a reconstructive technique of bicuspidizing the UAV. Initially we copied the typical asymmetry of a normal bicuspid aortic valve (BAV) (I), later we created a symmetric BAV (II). This study compared the hemodynamic function of the two designs of a bicuspidized UAV. Aortic valve function was studied at rest and during exercise in 28 patients after repair of UAV (group I, n = 8; group II, n = 20). There were no differences among the groups I and II with respect to gender, age, body size, or weight. All patients were in New York Heart Association class I. Six healthy adults served as control individuals. All patients were studied with transthoracic echocardiography between 4 and 65 months postoperatively. Systolic gradients were assessed by continuous wave Doppler while patients were at rest and exercising on a bicycle ergometer. Aortic regurgitation was grade I or less in all patients. Resting gradients were significantly elevated in group I compared with group II and control individuals (group I, peak 33.8 ± 7.8 mm Hg; mean 19.1 ± 5.4 mm Hg; group II, peak 15.8 ± 5.4, mean 8.2 ± 2.8 mm Hg; control individuals, peak 6.0 ± 1.6, mean 3.2 ± 0.8 mm Hg; p competence. A symmetric repair design leads to improved systolic aortic valve function at rest and during exercise. Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Long-Term Follow-Up of Percutaneous Balloon Angioplasty in Adult Aortic Coarctation

International Nuclear Information System (INIS)

Paddon, Alex J.; Nicholson, Anthony A.; Ettles, Duncan F.; Travis, Simon J.; Dyet, John F.

2000-01-01

Purpose: To assess long-term outcomes following percutaneous transluminal angioplasty (PTA) of congenital aortic coarctation in adults.Methods: Seventeen patients underwent PTA for symptomatic adult coarctation of the aorta. Sixteen patients, with a mean age of 28 years (range 15-60 years), were reviewed at a mean interval after angioplasty of 7.3 years (range 1.5-11 years). Assessment included magnetic resonance imaging (MRI), Doppler echocardiography, and clinical examination. Current clinical measurements were compared with pre- and immediate post-angioplasty measurements.Results: At follow-up 16 patients were alive and well. The patient not included in follow-up had undergone surgical repair and excision of the coarctation segment following PTA. Mean brachial systolic blood pressure for the group decreased from 174 mmHg before angioplasty to 130 mmHg at follow-up (p 0.0001). The mean gradient had fallen significantly from 50.9 to 17.8 at follow-up (p = 0.001). The average number of antihypertensive drugs required per patient decreased from 0.56 to 0.31 (p = 0.234). No significant residual stenoses or restenoses were seen at MRI. Small but clinically insignificant residual pressure gradients were recorded in all patients using Doppler echocardiography. Complications included one transient ischemic attack at 5 days, one external iliac dissection requiring stent insertion, and a further patient who developed a false aneurysm close to the coarctation site at 12 months which subsequently required surgical excision.Conclusion: PTA of adult coarctation is safe and effective in the long term. Although primary stenting has recently been advocated in the treatment of this condition, our results suggest that PTA remains the treatment of choice

Aortic annulus and ascending aorta: Comparison of preoperative and periooperative measurement in patients with aortic stenosis

International Nuclear Information System (INIS)

Smid, Michal; Ferda, Jiri; Baxa, Jan; Cech, Jakub; Hajek, Tomas; Kreuzberg, Boris; Rokyta, Richard

2010-01-01

Background: Precise determination of the aortic annulus size constitutes an integral part of the preoperative evaluation prior to aortic valve replacement. It enables the estimation of the size of prosthesis to be implanted. Knowledge of the size of the ascending aorta is required in the preoperative analysis and monitoring of its dilation enables the precise timing of the operation. Our goal was to compare the precision of measurement of the aortic annulus and ascending aorta using magnetic resonance (MR), multidetector-row computed tomography (MDCT), transthoracic echocardiography (TTE), and transoesophageal echocardiography (TEE) in patients with degenerative aortic stenosis. Methods and results: A total of 15 patients scheduled to have aortic valve replacement were enrolled into this prospective study. TTE was performed in all patients and was supplemented with TEE, CT and MR in the majority of patients. The values obtained were compared with perioperative measurements. For the measurement of aortic annulus, MR was found to be the most precise technique, followed by MDCT, TTE, and TEE. For the measurement of ascending aorta, MR again was found to be the most precise technique, followed by MDCT, TEE, and TTE. Conclusion: In our study, magnetic resonance was found to be the most precise technique for the measurement of aortic annulus and ascending aorta in patients with severe degenerative aortic stenosis.

Aortic arch malformations

Energy Technology Data Exchange (ETDEWEB)

Kellenberger, Christian J. [University Children' s Hospital, Department of Diagnostic Imaging, Zuerich (Switzerland)

2010-06-15

Although anomalies of the aortic arch and its branches are relatively uncommon malformations, they are often associated with congenital heart disease. Isolated lesions may be clinically significant when the airways are compromised by a vascular ring. In this article, the development and imaging appearance of the aortic arch system and its various malformations are reviewed. (orig.)

Aortic arch malformations

International Nuclear Information System (INIS)

Kellenberger, Christian J.

2010-01-01

Although anomalies of the aortic arch and its branches are relatively uncommon malformations, they are often associated with congenital heart disease. Isolated lesions may be clinically significant when the airways are compromised by a vascular ring. In this article, the development and imaging appearance of the aortic arch system and its various malformations are reviewed. (orig.)

The ballooning of fuel cladding tubes: theory and experiment

International Nuclear Information System (INIS)

Shewfelt, R.S.W.

1988-01-01

Under some conditions, fuel clad ballooning can result in considerable strain before rupture. If ballooning were to occur during a loss-of-coolant accident (LOCA), the resulting substantial blockage of the sub-channel would restrict emergency core cooling. However, circumferential temperature gradients that would occur during a LOCA may significantly limit the average strain at failure. Understandably, the factors that control ballooning and rupture of fuel clad are required for the analysis of a LOCA. Considerable international effort has been spent on studying the deformation of Zircaloy fuel cladding under conditions that would occur during a LOCA. This effort has established a reasonable understanding of the factors that control the ballooning, failure time, and average failure strain of fuel cladding. In this paper, both the experimental and theoretical studies of the fuel clad ballooning are reviewed. (author)

Aortic distensibility after aortic root replacement assessed with cardiovascular magnetic resonance.

Science.gov (United States)

Melina, Giovanni; Rajappan, Kim; Amrani, Mohamed; Khaghani, Asghar; Pennell, Dudley J; Yacoub, Magdi H

2002-01-01

The changes in geometry of the aortic root during the cardiac cycle are thought to be essential for optimal valve function, both in terms of leaflet stress and dynamic behavior. Using cardiac magnetic resonance (CMR), the study aim was to determine aortic root distensibility of the homograft (group H) and the Medtronic Freestyle xenograft (group F) after aortic root replacement, from a prospective randomized trial. CMR was performed in 15 patients (six homografts, nine Freestyle) at six months and one year after surgery. Percentage change in aortic radius (PCR) and pressure strain elastic modulus (PSEM) were measured as indices of distensibility, and results related to left ventricular mass (LVM). At six months after surgery, mean PCR was 12+/-2.5 in group H and 12.9+/-6.1 in group F (p = NS), and PSEM was 428.5+/-69.8 and 493.5+/-72.7 g/cm2, respectively (p = NS). PCR was reduced to 10+/-1.7% in group H, and by 8.5+/-2.8% in group F (p = NS), while PSEM was increased to 520.5+/-87.3 and 825+/-420.4, respectively (p = NS) at the one-year follow up. Regression analysis showed a correlation between PCR and LVM (r = 0.52, p = 0.08) and LVM index (r = 0.46, p = 0.14), respectively. In addition, there was a relationship between PSEM, LVM and LVM index, suggesting that the stiffer the root wall, the higher the postoperative LVM. Up to one year after aortic root replacement, the wall of both the allogenic and xenogenic valves retained near-normal distensibility. For the first time, a correlation was demonstrated between the elastic properties of the aortic root and LVM. The longer-term behavior and clinical implications of these findings require further investigation.

Ascending aortic injuries following blunt trauma.

Science.gov (United States)

Sun, Xiumei; Hong, Jenny; Lowery, Robert; Goldstein, Steven; Wang, Zuyue; Lindsay, Joseph; Hill, Peter C; Corso, Paul J

2013-11-01

The diagnosis and the management of traumatic thoracic aortic injuries have undergone significant changes due to new technology and improved prehospital care. Most of the discussions have focused on descending aortic injuries. In this review, we discuss the recent management of ascending aortic injuries. We found 5 cohort studies on traumatic aortic injuries and 11 case reports describing ascending aortic injuries between 1998 to the present through Medline research. Among case reports, 78.9% of cases were caused by motor vehicle accidents (MVA). 42.1% of patients underwent emergent open repair and the operative mortality was 12.5%. 36.8% underwent delayed repair. Associated injuries occurred in 84.2% of patients. Aortic valve injury was concurrent in 26.3% of patients. The incidence of ascending aortic injury ranged 1.9-20% in cohort studies. Traumatic injuries to the ascending aorta are relatively uncommon among survivors following blunt trauma. Aortography has been replaced by computed tomography and echocardiography as a diagnostic tool. Open repair, either emergent or delayed, remains the treatment of choice. © 2013 Wiley Periodicals, Inc.

Numerical research on the thermal performance of high altitude scientific balloons

International Nuclear Information System (INIS)

Dai, Qiumin; Xing, Daoming; Fang, Xiande; Zhao, Yingjie

2017-01-01

Highlights: • A model is presented to evaluate the IR radiation between translucent surfaces. • Comprehensive ascent and thermal models of balloons are established. • The effect of IR transmissivity on film temperature distribution is unneglectable. • Atmospheric IR radiation is the primary thermal factor of balloons at night. • Solar radiation is the primary thermal factor of balloons during the day. - Abstract: Internal infrared (IR) radiation is an important factor that affects the thermal performance of high altitude balloons. The internal IR radiation is commonly neglected or treated as the IR radiation between opaque gray bodies. In this paper, a mathematical model which considers the IR transmissivity of the film is proposed to estimate the internal IR radiation. Comprehensive ascent and thermal models for high altitude scientific balloons are established. Based on the models, thermal characteristics of a NASA super pressure balloon are simulated. The effects of film IR property on the thermal behaviors of the balloon are discussed in detail. The results are helpful for the design and operation of high altitude scientific balloons.

Can early aortic root surgery prevent further aortic dissection in Marfan syndrome?

Science.gov (United States)

Shimizu, Hideyuki; Kasahara, Hirofumi; Nemoto, Atsushi; Yamabe, Kentaro; Ueda, Toshihiko; Yozu, Ryohei

2012-02-01

We reviewed 50 patients with Marfan syndrome who underwent surgery for aortic root pathologies comprising a root aneurysm without (n = 25; group A) and with (n = 25; group B) dissection. Aortic root repair included Bentall (n = 37) and valve-sparing (n = 13) procedures. Hospital mortality was 4.0%. Twenty-two patients required 36 repeat surgeries on the distal aorta. The main indication for re-intervention was the dilation of the false lumen. In group A, the distal aorta was stable for up to 7 years, but new dissection developed in 5 (33.3%) of the 15 patients who were followed up for >7 years after the root repair. Actuarial survival including operative mortality was 88.1 and 65.0% at 10 and 20 years, respectively; groups A and B did not significantly differ. Rates of freedom from all-cause death, new dissection or repeated aortic surgery were 60.1, 44.5 and 26.0% at 5, 10 and 15 years, respectively. Group A was significantly better than group B. Prophylactic aortic root repair apparently reduces the likelihood of overall adverse events, but it cannot guarantee the prevention of further aortic dissection. A multidisciplinary approach is needed for patients with Marfan syndrome.

Adjustable continence balloons

DEFF Research Database (Denmark)

Kjær, Line; Fode, Mikkel; Nørgaard, Nis

2012-01-01

Abstract Objective. This study aimed to evaluate the results of the Danish experience with the ProACT urinary continence device inserted in men with stress urinary incontinence. Material and methods. The ProACT was inserted in 114 patients. Data were registered prospectively. The main endpoints...... in urinary leakage > 50% was seen in 72 patients (80%). Complications were seen in 23 patients. All of these were treated successfully by removal of the device in the outpatient setting followed by replacement of the device. Another eight patients had a third balloon inserted to improve continence further....... Fourteen patients (12%) ended up with an artificial sphincter or a urethral sling. Sixty patients (63%) experienced no discomfort and 58 (61%) reported being dry or markedly improved. Overall, 50 patients (53%) reported being very or predominantly satisfied. Conclusions. Adjustable continence balloons seem...

Thromboembolic events associated with single balloon-, double balloon-, and stent-assisted coil embolization of asymptomatic unruptured cerebral aneurysms: evaluation with diffusion-weighted MR imaging

International Nuclear Information System (INIS)

Takigawa, Tomoji; Suzuki, Kensuke; Sugiura, Yoshiki; Suzuki, Ryotaro; Takano, Issei; Shimizu, Nobuyuki; Tanaka, Yoshihiro; Hyodo, Akio

2014-01-01

The introduction of the balloon remodeling and stent-assisted technique has revolutionized the approach to coil embolization for wide-neck aneurysms. The purpose of this study was to determine the frequency of thromboembolic events associated with single balloon-assisted, double balloon-assisted, and stent-assisted coil embolization for asymptomatic unruptured aneurysms. A retrospective review was undertaken by 119 patients undergoing coiling with an adjunctive technique for unruptured saccular aneurysms (64 single balloon, 12 double balloon, 43 stent assisted). All underwent diffusion-weighted imaging (DWI) within 24 h after the procedure. DWI showed hyperintense lesions in 48 (40 %) patients, and ten (21 %) of these patients incurred neurological deterioration (permanent, two; transient, eight). Hyperintense lesions were detected significantly more often in procedures with the double balloon-assisted technique (7/12, 58 %) than with the single balloon-assisted technique (16/64, 25 %, p = 0.05). Occurrence of new lesions was significantly higher with the use of stent-assisted technique (25/43, 58 %) than with the single balloon-assisted technique (p = 0.001). Symptomatic ischemic rates were similar between the three groups. The increased number of microcatheters was significantly related to the DWI abnormalities (two microcatheters, 15/63 (23.8 %); three microcatheters, 20/41 (48.8 %) (p = 0.008); four microcatheters, 12/15 (80 %) (p = 0.001)). Thromboembolic events detected on DWI related to coil embolization for unruptured aneurysms are relatively common, especially in association with the double balloon-assisted and stent-assisted techniques. Furthermore, the number of microcatheters is highly correlated with DWI abnormalities. The high rate of thromboembolic events suggests the need for evaluation of platelet reactivity and the addition or change of antiplatelet agents. (orig.)

A History of Thoracic Aortic Surgery.

Science.gov (United States)

McFadden, Paul Michael; Wiggins, Luke M; Boys, Joshua A

2017-08-01

Ancient historical texts describe the presence of aortic pathology conditions, although the surgical treatment of thoracic aortic disease remained insurmountable until the 19th century. Surgical treatment of thoracic aortic disease then progressed along with advances in surgical technique, conduit production, cardiopulmonary bypass, and endovascular technology. Despite radical advances in aortic surgery, principles established by surgical pioneers of the 19th century hold firm to this day. Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of acute dietary nitrate supplementation on aortic blood pressure and aortic augmentation index in young and older adults.

Science.gov (United States)

Hughes, William E; Ueda, Kenichi; Treichler, David P; Casey, Darren P

2016-09-30

Aging is associated with elevated blood pressure (peripheral and aortic; BP) and aortic augmentation index (AIx) which may contribute to aortic BP. Although inorganic nitrate consumption reduces peripheral BP in both young and older adults, the effects of nitrate consumption on aortic BP and wave reflection in young and older adults is unknown. Therefore, we sought to characterize the effects of nitrate consumption on aortic BP and AIx in young and older adults. Noninvasive aortic pressure waveforms were synthesized from high-fidelity radial pressure waveforms via applanation tonometry before and following (60, 90, 120, 150, and 180 min) consumption of a nitrate-rich beetroot juice in 26 healthy adults (young: 25 ± 4 years, n = 14; older: 64 ± 5 years, n = 12). Aortic BP and indices of aortic wave reflection (AIx and AIx normalized for heart rate; AIx@75bpm) were calculated from the generated aortic pressure waveform. Nitrate consumption increased plasma nitrite in both groups 60-180 min following beetroot consumption (P young and older adults (P age groups. Conversely, indices of aortic wave reflection were reduced only in young adults following nitrate consumption (range of change from baseline over time: AIx@75bpm, -4.3 to -8.8%, P adults. Taken together, our results suggest that acute dietary nitrate supplementation reduces peripheral and aortic BP similarly in young and older adults despite differential effects on aortic AIx between age groups. Copyright © 2016 Elsevier Inc. All rights reserved.

Analysis of current diffusive ballooning mode

International Nuclear Information System (INIS)

Yagi, M.; Azumi, M.; Itoh, K.; Itoh, S.; Fukuyama, A.

1993-04-01

The current diffusive ballooning mode is analysed in the tokamak plasma. This mode is destabilized by the current diffusivity (i.e., the electron viscosity) and stabilized by the thermal conductivity and ion viscosity. By use of the ballooning transformation, the eigenmode equation is solved. Analytic solution is obtained by the strong ballooning limit. Numerical calculation is also performed to confirm the analytic theory. The growth rate of the mode and the mode structure are analysed. The stability boundary is derived in terms of the current diffusivity, thermal conductivity, ion viscosity and the pressure gradient for the given shear parameter. This result is applied to express the thermal conductivity in terms of the pressure gradient, magnetic configurational parameters (such as the safety factor, shear and aspect ratio) and the Prandtl numbers. (author)

Design and evaluation of a continuum robot with extendable balloons

Directory of Open Access Journals (Sweden)

E. Y. Yarbasi

2018-02-01

Full Text Available This article presents the design and preliminary evaluation of a novel continuum robot actuated by two extendable balloons. Extendable balloons are utilized as the actuation mechanism of the robot, and they are attached to the tip from their slack sections. These balloons can extend very much in length without having a significant change in diameter. Employing two balloons in an axially extendable, radially rigid flexible shaft, radial strain becomes constricted, allowing high elongation. As inflated, the balloons apply a force on the wall of the tip, pushing it forward. This force enables the robot to move forward. The air is supplied to the balloons by an air compressor and its flow rate to each balloon can be independently controlled. Changing the air volumes differently in each balloon, when they are radially constricted, orients the robot, allowing navigation. Elongation and force generation capabilities and pressure data are measured for different balloons during inflation and deflation. Afterward, the robot is subjected to open field and maze-like environment navigation tests. The contribution of this study is the introduction of a novel actuation mechanism for soft robots to have extreme elongation (2000 % in order to be navigated in substantially long and narrow environments.

Association of aortic valve calcification severity with the degree of aortic regurgitation after transcatheter aortic valve implantation.

Science.gov (United States)

Koos, Ralf; Mahnken, Andreas Horst; Dohmen, Guido; Brehmer, Kathrin; Günther, Rolf W; Autschbach, Rüdiger; Marx, Nikolaus; Hoffmann, Rainer

2011-07-15

This study sought to examine a possible relationship between the severity of aortic valve calcification (AVC), the distribution of AVC and the degree of aortic valve regurgitation (AR) after transcatheter aortic valve implantation (TAVI) for severe aortic stenosis (AS). 57 patients (22 men, 81 ± 5 years) with symptomatic AS and with a logistic EuroSCORE of 24 ± 12 were included. 38 patients (67%) received a third (18F)-generation CoreValve® aortic valve prosthesis, in 19 patients (33%) an Edwards SAPIEN™ prosthesis was implanted. Prior to TAVI dual-source computed tomography for assessment of AVC was performed. To determine the distribution of AVC the percentage of the calcium load of the most severely calcified cusp was calculated. After TAVI the degree of AR was determined by angiography and echocardiography. The severity of AR after TAVI was related to the severity and distribution of AVC. There was no association between the distribution of AVC and the degree of paravalvular AR after TAVI as assessed by angiography (r = -0.02, p = 0.88). Agatston AVC scores were significantly higher in patients with AR grade ≥ 3 (5055 ± 1753, n = 3) than in patients with AR grade AVC scores > 3000 were associated with a relevant paravalvular AR and showed a trend for increased need for second manoeuvres. There was a significant correlation between the severity of AVC and the degree of AR after AVR (r = 0.50, p AVC have an increased risk for a relevant AR after TAVI as well as a trend for increased need for additional procedures. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

The adventitia layer modulates the arterial wall elastic response to intra-aortic counterpulsation: in vivo studies.

Science.gov (United States)

Cabrera-Fischer, Edmundo I; Bia, Daniel; Zócalo, Yanina; Wray, Sandra; Armentano, Ricardo

2013-12-01

There is a relationship between the intra-aortic balloon pumping (IABP) benefits and the dynamic behavior of muscular arteries, which is associated with induced changes on the vessel walls through an endothelial-dependent mechanism. The arterial wall elastic behavior is influenced by adventitial function; however, no studies were performed in order to elucidate if this layer plays a role in the changes determined by IABP. Our aim was to quantify acute IABP effects on the mechanical properties of muscular arteries in induced acute heart failure (AHF), before and after adventitia removal. Pressure and diameter were recorded in the iliac arteries (IA) of sheep (n = 7), before and during 1:2 IABP: (i) in control state (CS) with intact IA, (ii) in CS after IA adventitia removal, and (iii) in de-adventitialized IA after AHF. Conduit function, compliance and arterial distensibility were calculated in each state. During CS, IABP resulted in intact IA dilatation and in an increase in conduit function, compliance and distensibility; adventitial removal determined an increase of arterial stiffness with respect to the CS, which decreased when IABP was used; the increase in arterial stiffness observed after adventitia removal was also detected in AHF state; IABP improves conduit function and arterial stiffness in de-adventitialized arteries, both before and during AHF. However, the improvement in these properties was lower than in intact arteries. Before and after AHF induction, the improvements of conduit function and arterial distensibility determined by IABP in intact IA were significantly reduced after adventitia removal. Adventitial layer integrity would be necessary to maximize IABP-related beneficial effects on arterial system properties. © 2013 Wiley Periodicals, Inc. and International Center for Artificial Organs and Transplantation.

Design and principle of operation of the HeartMate PHP (percutaneous heart pump).

Science.gov (United States)

Van Mieghem, Nicolas M; Daemen, Joost; den Uil, Corstiaan; Dur, Onur; Joziasse, Linda; Maugenest, Anne-Marie; Fitzgerald, Keif; Parker, Chris; Muller, Paul; van Geuns, Robert-Jan

2018-02-20

The HeartMate PHP (percutaneous heart pump) is a second-generation transcatheter axial flow circulatory support system. The collapsible catheter pump is inserted through a 14 Fr sheath, deployed across the aortic valve expanding to 24 Fr and able to deliver up to 5 L/min blood flow at minimum haemolytic risk. As such, this device may be a valuable adjunct to percutaneous coronary intervention (PCI) of challenging lesions in high-risk patients or treatment of cardiogenic shock. This technical report discusses: (i) the HeartMate PHP concept, (ii) the implantation technique, (iii) the haemodynamic performance in an in vitro cardiovascular flow testing set-up, and (iv) preliminary clinical experience. An update on the device, produced by St. Jude Medical/Abbott Laboratories, can be found in the Appendix.

Innovations in Balloon Catheter Technology in Rhinology.

Science.gov (United States)

D'Anza, Brian; Sindwani, Raj; Woodard, Troy D

2017-06-01

Since being introduced more than 10 years ago, balloon catheter technology (BCT) has undergone several generations of innovations. From construction to utilization, there has been a myriad of advancements in balloon technology. The ergonomics of the balloon dilation systems have improved with a focus on limiting the extra assembly. "Hybrid" BCT procedures have shown promise in mucosal preservation, including treating isolated complex frontal disease. Multiple randomized clinical trials report improved long-term outcomes in stand-alone BCT, including in-office use. The ever-expanding technological innovations ensure BCT will be a key component in the armamentarium of the modern sinus surgeon. Copyright © 2017 Elsevier Inc. All rights reserved.

Fluorescence Lyman-Alpha Stratospheric Hygrometer (FLASH): application on meteorological balloons, long duration balloons and unmanned aerial vehicles.

Science.gov (United States)

Lykov, Alexey; Khaykin, Sergey; Yushkov, Vladimir; Efremov, Denis; Formanyuk, Ivan; Astakhov, Valeriy

The FLASH instrument is based on the fluorescent method, which uses H2O molecules photodissociation at a wavelength lambda=121.6 nm (Lalpha - hydrogen emission) followed by the measurement of the fluorescence of excited OH radicals. The source of Lyman-alpha radiation is a hydrogen discharge lamp while the detector of OH fluorescence at 308 -316 nm is a photomultiplier run in photon counting mode. The intensity of the fluorescent light as well as the instrument readings is directly proportional to the water vapor mixing ratio under stratospheric conditions with negligible oxygen absorption. Initially designed for rocket-borne application, FLASH has evolved into a light-weight balloon sonde (FLASH-B) for measurements in the upper troposphere and stratosphere on board meteorological and small plastic balloons. This configuration has been used in over 100 soundings at numerous tropical mid-latitude and polar locations within various international field campaigns. An airborne version of FLASH instrument is successfully utilized onboard stratospheric M55-Geophysica aircraft and tropospheric airborne laboratory YAK42-Roshydromet. The hygrometer was modified for application onboard stratospheric long-duration balloons (FLASH-LDB version). This version was successfully used onboard CNES super-pressure balloon launched from SSC Esrange in March 2007 and flown during 10 days. Special design for polar long duration balloon PoGOLite was created for testing work during polar day in June 2013. Installation and measurement peculiarities as well as observational results are presented. Observations of water vapour using FLASH-B instrument, being of high quality are rather costly as the payload recovery is often complicated and most of the time impossible. Following the goal to find a cost-efficient solution, FLASH was adapted for use onboard Unmanned Aerial Vehicles (UAV). This solution was only possible thanks to compactness and light-weight (0.5 kg) of FLASH instrument. The

Rectal Balloon for the Immobilization of the Prostate Internal Motion

International Nuclear Information System (INIS)

Lee, Sang Kyu; Beak, Jong Geal; Kim, Joo Ho; Jeon, Byong Chul; Cho, Jeong Hee; Kim, Dong Wook; Song, Tae Soo; Cho, Jae Ho; Na, Soo Kyong

2005-01-01

The using of endo-rectal balloon has proposed as optimal method that minimized the motion of prostate and the dose of rectum wall volume for treated prostate cancer patients, so we make the customized rectal balloon device. In this study, we analyzed the efficiency of the Self-customized rectal balloon in the aspects of its reproducibility. In 5 patients, for treatment planning, each patient was acquired CT slice images in state of with and without rectal balloon. Also they had CT scanning same repeated third times in during radiation treatment (IMRT). In each case, we analyzed the deviation of rectal balloon position and verified the isodose distribution of rectum wall at closed prostate. Using the rectal balloon, we minimized the planning target volume (PTV) by decreased the internal motion of prostate and overcome the dose limit of radiation therapy in prostate cancer by increased the gap between the rectum wall and high dose region. The using of rectal balloon, although, was reluctant to treat by patients. View a point of immobilization of prostate internal motion and dose escalation of GTV (gross tumor volume), its using consider large efficient for treated prostate cancer patients.

Robotic aortic surgery.

Science.gov (United States)

Duran, Cassidy; Kashef, Elika; El-Sayed, Hosam F; Bismuth, Jean

2011-01-01

Surgical robotics was first utilized to facilitate neurosurgical biopsies in 1985, and it has since found application in orthopedics, urology, gynecology, and cardiothoracic, general, and vascular surgery. Surgical assistance systems provide intelligent, versatile tools that augment the physician's ability to treat patients by eliminating hand tremor and enabling dexterous operation inside the patient's body. Surgical robotics systems have enabled surgeons to treat otherwise untreatable conditions while also reducing morbidity and error rates, shortening operative times, reducing radiation exposure, and improving overall workflow. These capabilities have begun to be realized in two important realms of aortic vascular surgery, namely, flexible robotics for exclusion of complex aortic aneurysms using branched endografts, and robot-assisted laparoscopic aortic surgery for occlusive and aneurysmal disease.

[Aortic valve-sparing root reconstruction in Marfan syndrome].

Science.gov (United States)

Ogino, H; Sasaki, H; Hanafusa, Y; Hirata, M; Numata, S; Ando, M; Yagihara, T; Kitamura, S

2002-07-01

The outcome of aortic valve-sparing root reconstruction in Marfan syndrome was reviewed. Thirteen patients with Marfan syndrome underwent aortic valve-sparing root reconstruction for annuloaortic ectasia or aortic root dissection between 1994 and 1999. The grade of preoperative aortic regurgitation was I in 4, II in 2, III in 5, IV in 2 patients. The procedures of aortic valve-sparing were reimplantation in 7 and remodeling in 5 patients. There was no hospital and late death. Recurrence of aortic regurgitation greater than moderate grade developed in 1 patient immediately after the surgery and in the other 4 patients in the late stage. One patient of them required aortic valve replacement for it. Aortic valve-sparing root reconstruction is applicable in Marfan patients, although the indication should be cautious. Close observation is needed for recurrence of aortic regurgitation.

Bicuspid aortic valves: Diagnostic accuracy of standard axial 64-slice chest CT compared to aortic valve image plane ECG-gated cardiac CT

Energy Technology Data Exchange (ETDEWEB)

Murphy, David J., E-mail: david.murphy@st-vincents.ie [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland); McEvoy, Sinead H., E-mail: s.mcevoy@st-vincents.ie [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland); Iyengar, Sri, E-mail: sri.iyengar@nhs.net [Department of Radiology, Plymouth Hospitals NHS Trust, Plymouth Devon PL6 8DH (United Kingdom); Feuchtner, Gudrun, E-mail: Gudrun.Feuchtner@i-med.ac.at [Department of Radiology, Innsbruck Medical University, Anichstr. 35, A-6020 Innsbruck (Austria); Cury, Ricardo C., E-mail: r.cury@baptisthealth.net [Department of Radiology, Baptist Cardiac and Vascular Institute, 8900 North Kendall Drive, Miami, FL 33176 (United States); Roobottom, Carl, E-mail: carl.roobottom@nhs.net [Department of Radiology, Plymouth Hospitals NHS Trust, Plymouth Devon PL6 8DH (United Kingdom); Plymouth University Peninsula Schools of Medicine and Dentistry (United Kingdom); Baumueller, Stephan, E-mail: Hatem.Alkadhi@usz.ch [Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, CH-8091 Zurich (Switzerland); Alkadhi, Hatem, E-mail: stephan.baumueller@usz.ch [Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, CH-8091 Zurich (Switzerland); Dodd, Jonathan D., E-mail: jonniedodd@gmail.com [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland)

2014-08-15

Objectives: To assess the diagnostic accuracy of standard axial 64-slice chest CT compared to aortic valve image plane ECG-gated cardiac CT for bicuspid aortic valves. Materials and methods: The standard axial chest CT scans of 20 patients with known bicuspid aortic valves were blindly, randomly analyzed for (i) the appearance of the valve cusps, (ii) the largest aortic sinus area, (iii) the longest aortic cusp length, (iv) the thickest aortic valve cusp and (v) valve calcification. A second blinded reader independently analyzed the appearance of the valve cusps. Forty-two age- and sex-matched patients with known tricuspid aortic valves were used as controls. Retrospectively ECG-gated cardiac CT multiphase reconstructions of the aortic valve were used as the gold-standard. Results: Fourteen (21%) scans were scored as unevaluable (7 bicuspid, 7 tricuspid). Of the remainder, there were 13 evaluable bicuspid valves, ten of which showed an aortic valve line sign, while the remaining three showed a normal Mercedes-Benz appearance owing to fused valve cusps. The 35 evaluable tricuspid aortic valves all showed a normal Mercedes-Benz appearance (P = 0.001). Kappa analysis = 0.62 indicating good interobserver agreement for the aortic valve cusp appearance. Aortic sinus areas, aortic cusp lengths and aortic cusp thicknesses of ≥3.8 cm{sup 2}, 3.2 cm and 1.6 mm respectively on standard axial chest CT best distinguished bicuspid from tricuspid aortic valves (P < 0.0001 for all). Of evaluable scans, the sensitivity, specificity, positive and negative predictive values of standard axial chest CT in diagnosing bicuspid aortic valves was 77% (CI 0.54–1.0), 100%, 100% and 70% respectively. Conclusion: The aortic valve is evaluable in approximately 80% of standard chest 64-slice CT scans. Bicuspid aortic valves may be diagnosed on evaluable scans with good diagnostic accuracy. An aortic valve line sign, enlarged aortic sinuses and elongated, thickened valve cusps are specific CT

Aortic aneurysm disease vs. aortic occlusive disease - differences in outcome and intensive care resource utilisation after elective surgery

DEFF Research Database (Denmark)

Bisgaard, Jannie; Gilsaa, Torben; Rønholm, Ebbe

2013-01-01

clamping is more pronounced in patients with aortic aneurysm disease, which may affect outcome. OBJECTIVES: The aim of this observational cohort study was to evaluate outcome after open elective abdominal aortic surgery, hypothesising a higher 30-day mortality, a higher incidence of postoperative organ...... dysfunction and a longer length of stay in patients with aortic aneurysm compared with aortic occlusive disease. DESIGN: Cohort observational study based on prospective registrations from national databases. SETTING: Eight Danish hospitals, including four university and four non-university centres, from 1...... or inotropes, ICU stay more than 24 h, hospital length of stay and mortality. RESULTS: Compared with aortic occlusive disease, more patients with aortic aneurysm disease had ICU stays more than 24 h (62 vs. 45%, P ...

Development of radioactive 166Ho-coated balloon and its dose estimation

International Nuclear Information System (INIS)

Park, K. B.; Kim, K. H.; Hong, Y. D.; Park, E. W.

2000-01-01

The use of balloon with radioisotope is a promising method to prevent restenosis after transluminal coronary arterial angioplasty or stent implantation. In this study, we have developed a new radioactive coated balloon, which is prepared by coating the surface of existing balloon with 166 Ho instead of being filled with beta sources which emit high energy beta-particles for the purpose of the delivery of sufficient radiation to the vessel wall. To estimate the safety of 166 Ho-coated balloon, leaching test and radiation resistance test of the balloon were performed. The absorbed dose distributions around the 166 Ho-coated balloon were estimated by means of Monte Carlo simulation and the initial activities for optimal therapeutic regimen were determined on the basis of this results

MRI evaluation of the aortic disease

International Nuclear Information System (INIS)

Kapuscinski, O.; Polkowski, J.; Zaleska, T.; Walecki, J.; Biesiadko, M.

1994-01-01

The goal of our study was to establish the value of MRI in diagnosing aortic disease. During 3 years period 46 patients were examined (12 women aged from 6 to 62 years and 34 men aged from 8 to 72 years). In 28 cases the thoracic aorta was examined, in 6 cases the abdominal aorta and in 12 - both the thoracic and the abdominal aorta. MR images were performed on MRT 50 A Toshiba unit 0.5 T. MR images demonstrated aortic aneurysm (caused by atherosclerosis or trauma), aortic dissections, aortic anomalies (i.e. in Turner syndrome) and non-specific aortitis and vasculitis. We regard MRI as preferable noninvasive imaging technique in diagnosing aortic disease. (author)

Aortic allografts in treatment of aortic valve and ascending aorta prosthetic endocarditis

Directory of Open Access Journals (Sweden)

S.V. Spiridonov

2017-03-01

Full Text Available The aim – to assess short- and long-term results of aortic root replacement using aortic allografts in patients with prosthetic endocarditis. Materials and methods. Since February 2009 until June 2016 aortic valve and ascending aorta replacement using aortic allografts was performed in 26 patients with prosthetic endocarditis. In 50 % of cases at initial operation aortic valve replacement was performed, in another 50 % of cases – aortic valve and ascending aorta replacement. Echocardiography was performed 10 days, 3, 6 and 12 months, 2, 3 and 5 years after surgery. Analysis of long-term results included all cases of deaths, prosthesis-related complications and recurrence of endocarditis. Results. 30-day mortality was 23.1 %. Extracorporeal membranous oxygenation (ECMO was used only in 5 patients (19.2 %. Four patients were weaned from ECMO. We did not observe any allograft-related complications. During follow-up period there were no cases of reoperation due to structural allograft failure. Relapse of infection occurred in 1 patient (3.8 % four years after the operation and led to lethal outcome. Conclusion. Reoperations using allografts are an effective surgical treatment of prosthetic endocarditis. In majority of cases prosthetic endocarditis was caused by gram-positive cocci (Staphylococcus. In 84.6 % of cases it was associated with destruction of paravalvular structures and abscesses formation. Heart failure was a causative factor of different complications in these patients, which required ECMO in 19.2 % of patients. In 80 % of cases patients were weaned from ECMO. Allografts using for the treatment of prosthetic endocarditis is associated with high resistance to infection and with a significant rate of freedom from recurrence of endocarditis within 3 years after surgery.

Transcatheter Aortic Valve Replacement by a Novel Suprasternal Approach.

Science.gov (United States)

Codner, Pablo; Pugliese, Daniel; Kouz, Rémi; Patel, Amisha; Chen, Cheng-Han; Terre, Juan; Eudailey, Kyle W; Nazif, Tamim; Vahl, Torsten P; George, Isaac; Khalique, Omar K; Hahn, Rebecca T; Leon, Martin B; Kodali, Susheel; Borger, Michael

2018-04-01

Transcatheter aortic valve replacement (TAVR) provides therapy for patients with severe aortic stenosis at extreme, high, or intermediate surgical risk. Transfemoral access has been the preferred access route; however, this approach is not suitable for many TAVR candidates. A suprasternal approach may allow for earlier ambulation and shorter hospital stay as compared with other, nontransfemoral approaches. A total of 11 patients with unsuitable transfemoral access underwent suprasternal TAVR. Propensity matching was used to compare suprasternal patients to patients undergoing transaortic, transapical, and trans-subclavian TAVR. Groups were well matched for baseline characteristics. A self-expanding valve device was used in 6 (54.5%) and a balloon-expandable valve in 5 (45.5%) of the 11 patients treated by the suprasternal route. Suprasternal and trans-subclavian patients were able to ambulate earlier than patients treated by the transaortic route, a median 1.6 days (interquartile range [IQR]: 0.9 to 1.8), 1.6 days (IQR: 0.9 to 2.7), and 3.9 days (IQR: 1.9 to 4.5) after the procedure for suprasternal, trans-subclavian, and transaortic patients, respectively (p = 0.001). Length of hospitalization was shorter for patients treated by suprasternal or trans-subclavian access in comparison with patients treated by the transaortic or transapical approach: median 4 days (IQR: 3 to 8) and 4 days (IQR: 4 to 8) versus 8 days (IQR: 6 to 14) and 6 days (IQR: 7 to 11) for suprasternal and trans-subclavian versus transaortic and transapical, respectively (p = 0.01). Suprasternal and trans-subclavian access are associated with earlier ambulation and shorter hospitalization than other nontransfemoral TAVR routes, without an increase in complications. Further study is required to determine if suprasternal is the alternative access of choice for TAVR patients with poor transfemoral vasculature. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights

Evaluation of Acute Aortic Dissection Type a Factors and Comparison the Postoperative Clinical Outcomes between Two Surgical Methods.

Science.gov (United States)

Shemirani, Hasan; Mirmohamadsadeghi, Amir; Mahaki, Behzad; Farhadi, Sadaf; Badalabadi, Reza Mohseni; Bidram, Peyman; Badalabadi, Mehdi Mohseni

2017-01-01

Although aortic dissection is a rare disease, it causes high level of mortality. If ascending aorta gets involved in this disease, it is known as type A. According to small number of studies about this disease in Iran, this study conducted to detect the factors related to acute aortic dissection type A, its surgery consequences and the factors affecting them. In this historical cohort study, all patients having acute aortic dissection type A referring to Chamran Hospital from 2006 to 2012 were studied. The impact of two surgical methods including antegrade cerebral perfusion (ACP) and retrograde cerebral one (RCP) on surgical and long-term mortality and recurrence of dissection was determined. The relation of mortality rate and hemodynamic instability before surgery, age more than 70 years old, ejection fraction lower than 50%, prolonged cardiopulmonary bypass pump (CPBP) time and excessive blood transfusion, was assessed. Surgery and long-term mortality and recurrence of dissection were 35.3%, 30.8% and 30.4%. Surgical and long-term death in the patients being operated by ACP method was lower than those one being operated by RCP ( P RCP according to the surgical and long-term mortality.

Gastric emptying and intragastric balloon in obese patients.

Science.gov (United States)

Bonazzi, P; Petrelli, M D; Lorenzini, I; Peruzzi, E; Nicolai, A; Galeazzi, R

2005-01-01

Intragastric balloons have been proposed to induce weight loss in obese subjects. The consequences of the balloon on gastric physiology remain poorly studied. We studied the influence of an intragastric balloon on gastric emptying in obese patients. 12 patients were included in the study, with BMI (mean +/- SD) of 38.51 +/- 4.32 kg/m2. The balloon was inserted under light anaesthesia and endoscopic control, inflated with 700 ml saline, and removed 6 months later. Body weight and gastric emptying (T1/2 and T lag) using 13C-octanoic acid breath test were monitored before balloon placement, during its permanence and 2 months after removal. Mean weight loss was: 6.2 +/- 2.3 kg after one month; 12.4 +/- 5.8 kg after 3 months; 14.4 +/- 6.6 kg after 6 months and 10.1 +/- 4.3 kg two months after BIB removal. Gastric emptying rates were significantly decreased in the first periods with balloon in place, and returned to pre-implantation values after balloon removal. T1/2 was: 87 +/- 32 min before BIB positioning, 181 +/- 91 min after 1 month, 145 +/- 99 min after 3 months, 104 +/- 50 min after 6 months and 90 +/- 43 min 2 months after removal. T lag was 36 +/- 18 min before BIB positioning, 102 +/- 82 min after 1 month, 77 +/- 53 min after 3 months, 59 +/- 28 min after 6 months and 40 +/- 21 min. 2 months after removal. BIB in obese patients seems to be a good help in following the hypo caloric diet, especially during the first three months when the gastric emptying is slower and the sense of repletion is higher. After this period gastric emptying starts to return to normal and the stomach adapts to BIB loosing efficacy in weight loss.

Balloon catheter dilatation in esophageal achalasia: long term follow-up

Energy Technology Data Exchange (ETDEWEB)

Shin, Cheol Yong; Park, Hyun Mee; Kim, So Eun; Lee, Shin Hyung; Kim, Seung Hyeon; Lee, Chang Joon [National Medical Center, Seoul (Korea, Republic of)

1994-12-15

To evaluate the clinical efficacy of balloon catheter dilatation in the treatment of esophageal achalasia. Seven patients(three males and four females) with esopha-geal achalasia were treated with balloon catheter dilatation. Balloon catheters of variable sizes were used depending on patient's conditions. The patients were followed up over a period of 12-39 months. Balloon catheter dilatation in esophageal achalasia was successful in all patients without esophageal perforation. All patients were relieved from dysphagia. Recurrence was not found in 5 patients on long term follow-up study, but was seen in 2 patients after 18 and 21 months, respectively. Balloon catheter dilatation was a safe and effective method in the treatment of esophageal achalasia with low recurrence rate of 29% on follow-up study.

Balloon catheter dilatation in esophageal achalasia: long term follow-up

International Nuclear Information System (INIS)

Shin, Cheol Yong; Park, Hyun Mee; Kim, So Eun; Lee, Shin Hyung; Kim, Seung Hyeon; Lee, Chang Joon

1994-01-01

To evaluate the clinical efficacy of balloon catheter dilatation in the treatment of esophageal achalasia. Seven patients(three males and four females) with esopha-geal achalasia were treated with balloon catheter dilatation. Balloon catheters of variable sizes were used depending on patient's conditions. The patients were followed up over a period of 12-39 months. Balloon catheter dilatation in esophageal achalasia was successful in all patients without esophageal perforation. All patients were relieved from dysphagia. Recurrence was not found in 5 patients on long term follow-up study, but was seen in 2 patients after 18 and 21 months, respectively. Balloon catheter dilatation was a safe and effective method in the treatment of esophageal achalasia with low recurrence rate of 29% on follow-up study

Ballooning Stability of the Compact Quasiaxially Symmetric Stellarator

International Nuclear Information System (INIS)

Redi, M.H.; Canik, J.; Dewar, R.L.; Johnson, J.L.; Klasky, S.; Cooper, W.A.; Kerbichler, W.

2001-01-01

The magnetohydrodynamic (MHD) ballooning stability of a compact, quasiaxially symmetric stellarator (QAS), expected to achieve good stability and particle confinement is examined with a method that can lead to estimates of global stability. Making use of fully 3D, ideal-MHD stability codes, the QAS beta is predicted to be limited above 4% by ballooning and high-n kink modes. Here MHD stability is analyzed through the calculation and examination of the ballooning mode eigenvalue isosurfaces in the 3-space [s, alpha, theta(subscript ''k'')]; s is the edge normalized toroidal flux, alpha is the field line variable, and theta(subscript ''k'') is the perpendicular wave vector or ballooning parameter. Broken symmetry, i.e., deviations from axisymmetry, in the stellarator magnetic field geometry causes localization of the ballooning mode eigenfunction, with new types of nonsymmetric, eigenvalue isosurfaces in both the stable and unstable spectrum. The isosurfaces around the most unstable points i n parameter space (well above marginal) are topologically spherical. In such cases, attempts to use ray tracing to construct global ballooning modes lead to a k-space runaway. Introduction of a reflecting cutoff in k(perpendicular) to model numerical truncation or finite Larmor radius (FLR) yields chaotic ray paths ergodically filling the allowed phase space, indicating that the global spectrum must be described using the language of quantum chaos theory. However, the isosurface for marginal stability in the cases studied are found to have a more complex topology, making estimation of FLR stabilization more difficult

Long-term animal experiments with an intraventricular axial flow blood pump.

Science.gov (United States)

Yamazaki, K; Kormos, R L; Litwak, P; Tagusari, O; Mori, T; Antaki, J F; Kameneva, M; Watach, M; Gordon, L; Mukuo, H; Umezu, M; Tomioka, J; Outa, E; Griffith, B P; Koyanagai, H

1997-01-01

A miniature intraventricular axial flow blood pump (IVAP) is undergoing in vivo evaluation in calves. The IVAP system consists of a miniature (phi 13.9 mm) axial flow pump that resides within the left ventricular (LV) chamber and a brushless DC motor. The pump is fabricated from titanium alloy, and the pump weight is 170 g. It produces a flow rate of over 5 L/min against 100 mmHg pressure at 9,000 rpm with an 8 W total power consumption. The maximum total efficiency exceeds 17%. A purged lip seal system is used in prototype no. 8, and a newly developed "Cool-Seal" (a low temperature mechanical seal) is used in prototype no. 9. In the Cool-Seal system, a large amount of purge flow is introduced behind the seal faces to augment convective heat transfer, keeping the seal face temperature at a low level for prevention of heat denaturation of blood proteins. The Cool-Seal system consumes < 10 cc purge fluid per day and has greatly extended seal life. The pumps were implanted in three calves (26, 30, and 168 days of support). The pump was inserted through a left thoracotomy at the fifth intercostal space. Two pursestring sutures were placed on the LV apex, and the apex was cored with a myocardial punch. The pump was inserted into the LV with the outlet cannula smoothly passing through the aortic valve without any difficulty. Only 5 min elapsed between the time of chest opening and initiation of pumping. Pump function remained stable throughout in all experiments. No cardiac arrhythmias were detected, even at treadmill exercise tests. The plasma free hemoglobin level remained in the acceptable range. Post mortem examination did not reveal any interference between the pump and the mitral apparatus. No major thromboembolism was detected in the vital organs in Cases 1 or 2, but a few small renal infarcts were detected in Case 3.

Balloon dilatation of the prostatic urethra

International Nuclear Information System (INIS)

Lee, Yeon Soo; Shim, Hyung Jin; Cha, Kyung Soo; Hong, Ju Hee; Lim, Myung Ah; Kim, Cheol Soo

1991-01-01

We analyzed the result of transurethral balloon dilatation in 11 patients with benign prostatic hypertrophy. The procedures were performed under intravenous sedation and local anesthesia with double lumen balloon catheter at 4 atmosphere for 10 minutes. After dilatation, the prostatism symptom scores improved in 10 out of 11 patients and the mean diameter of the prostatic urethra significantly increased form 4.3 mm to 10.2 mm (ρ < 0.005). The procedures were successful not only in lateral lobe hypertrophy but also in median lobe hypertrophy of the prostate. Postdilatation MRI of 1 patient showed an intact prostatic capsule and no periprostatic hematoma. Complications did not develop except in 1 patient with mild hematuria and incontinence. These preliminary results suggest that transurethral balloon dilatation can be an effective and safe treatment modality for benign prostatic hypertrophy

Wind-Driven Montgolfiere Balloons for Mars

Science.gov (United States)

Jones, Jack A.; Fairbrother, Debora; Lemieux, Aimee; Lachenmeier, Tim; Zubrin, Robert

2005-01-01

Solar Montgolfiere balloons, or solar-heated hot air balloons have been evaluated by use on Mars for about 5 years. In the past, JPL has developed thermal models that have been confirmed, as well as developed altitude control systems to allow the balloons to float over the landscape or carry ground sampling instrumentation. Pioneer Astronautics has developed and tested a landing system for Montgolfieres. JPL, together with GSSL. have successfully deployed small Montgolfieres (<15-m diameter) in the earth's stratosphere, where conditions are similar to a Mars deployment. Two larger Montgolfieres failed, however, and a series of larger scale Montgolfieres is now planned using stronger, more uniform polyethylene bilaminate, combined with stress-reducing ripstitch and reduced parachute deceleration velocities. This program, which is presently under way, is a joint effort between JPL, WFF, and GSSL, and is planned for completion in three years.

Overexpression of interleukin-1β and interferon-γ in type I thoracic aortic dissections and ascending thoracic aortic aneurysms: possible correlation with matrix metalloproteinase-9 expression and apoptosis of aortic media cells.

Science.gov (United States)

Zhang, Lei; Liao, Ming-fang; Tian, Lei; Zou, Si-li; Lu, Qing-sheng; Bao, Jun-min; Pei, Yi-fei; Jing, Zai-ping

2011-07-01

To examine the expression of interleukin-1β and interferon-γ and their possible roles in aortic dissections and aneurysms. Aortic specimens were obtained from patients with type I thoracic aortic dissection, ascending thoracic aortic aneurysms, and control organ donors. The expression of interleukin-1β, interferon-γ, matrix metalloproteinase-9, and signal transduction factors phospho-p38 and phosphorylated c-jun N-terminal kinase (phospho-JNK) were detected by real time reverse transcription-polymerase chain reaction (real time RT-PCR), Western blot, and immunohistochemistry, respectively. Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining was performed to detect apoptosis of media cells. The correlation of these factors and apoptosis was also studied. Apoptosis in the media of thoracic aortic dissection and in ascending thoracic aortic aneurysms was dramatically higher than in the control group. The expression of interleukin-1β gradually increased from the control group, thoracic aortic dissection to ascending thoracic aortic aneurysms (p matrix metalloproteinase-9 was significantly increased in the media of thoracic aortic dissection and ascending thoracic aortic aneurysms compared with the control group (p correlations between interleukin-1β versus matrix metalloproteinase-9, interleukin-1β versus phospho-p38 in thoracic aortic dissection (p matrix metalloproteinase-9, interferon-γ versus phospho-JNK, interferon-γ versus apoptosis, and interleukin-1β versus apoptosis in ascending thoracic aortic aneurysms (p = 0.02, 0.02, p matrix metalloproteinase-9 and the apoptosis of media cells in humans. Copyright © 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Aerial Deployment and Inflation System for Mars Helium Balloons

Science.gov (United States)

Lachenmeler, Tim; Fairbrother, Debora; Shreves, Chris; Hall, Jeffery, L.; Kerzhanovich, Viktor V.; Pauken, Michael T.; Walsh, Gerald J.; White, Christopher V.

2009-01-01

A method is examined for safely deploying and inflating helium balloons for missions at Mars. The key for making it possible to deploy balloons that are light enough to be buoyant in the thin, Martian atmosphere is to mitigate the transient forces on the balloon that might tear it. A fully inflated Mars balloon has a diameter of 10 m, so it must be folded up for the trip to Mars, unfolded upon arrival, and then inflated with helium gas in the atmosphere. Safe entry into the Martian atmosphere requires the use of an aeroshell vehicle, which protects against severe heating and pressure loads associated with the hypersonic entry flight. Drag decelerates the aeroshell to supersonic speeds, then two parachutes deploy to slow the vehicle down to the needed safe speed of 25 to 35 m/s for balloon deployment. The parachute system descent dynamic pressure must be approximately 5 Pa or lower at an altitude of 4 km or more above the surface.

A geometric reappraisal of proximal landing zones for thoracic endovascular aortic repair according to aortic arch types

NARCIS (Netherlands)

Marrocco-Trischitta, Massimiliano M.; de Beaufort, Hector W.; Secchi, Francesco; van Bakel, Theodorus M.; Ranucci, Marco; van Herwaarden, Joost A.; Moll, Frans L.; Trimarchi, Santi

Objective: This study assessed whether the additional use of the aortic arch classification in type I, II, and III may complement Ishimaru's aortic arch map and provide valuable information on the geometry and suitability of proximal landing zones for thoracic endovascular aortic repair. Methods:

Viscoelastic behaviour of pumpkin balloons

Science.gov (United States)

Gerngross, T.; Xu, Y.; Pellegrino, S.

2008-11-01

The lobes of the NASA ULDB pumpkin-shaped super-pressure balloons are made of a thin polymeric film that shows considerable time-dependent behaviour. A nonlinear viscoelastic model based on experimental measurements has been recently established for this film. This paper presents a simulation of the viscoelastic behaviour of ULDB balloons with the finite element software ABAQUS. First, the standard viscoelastic modelling capabilities available in ABAQUS are examined, but are found of limited accuracy even for the case of simple uniaxial creep tests on ULDB films. Then, a nonlinear viscoelastic constitutive model is implemented by means of a user-defined subroutine. This approach is verified by means of biaxial creep experiments on pressurized cylinders and is found to be accurate provided that the film anisotropy is also included in the model. A preliminary set of predictions for a single lobe of a ULDB is presented at the end of the paper. It indicates that time-dependent effects in a balloon structure can lead to significant stress redistribution and large increases in the transverse strains in the lobes.

Aortic elongation in aortic aneurysm and dissection: the Tübingen Aortic Pathoanatomy (TAIPAN) project.

Science.gov (United States)

Krüger, Tobias; Sandoval Boburg, Rodrigo; Lescan, Mario; Oikonomou, Alexandre; Schneider, Wilke; Vöhringer, Luise; Lausberg, Henning; Bamberg, Fabian; Blumenstock, Gunnar; Schlensak, Christian

2018-01-24

To study the lengths and diameters of aortic segments in healthy and diseased aortas and to assess the role of aortic elongation in Type A aortic dissection (TAD) prediction. Ectasia and aneurysm were defined by ascending aorta diameters of 45-54 mm and ≥55 mm, respectively. Computed tomography angiography studies of 256 healthy, 102 ectasia, 38 aneurysm, 17 pre-TAD and 166 TAD aortas were analysed using curved multiplanar reformats. The study groups were structurally equal. The diameter of the ascending aorta was 35 mm in the control group and was larger (P TAD (43 mm) and TAD (56 mm) groups. The length of the ascending aorta from the aortic annulus to the brachiocephalic trunk was 92 mm in the control group, 113 mm in the ectasia group, 120 mm in the aneurysm group and 111 mm and 118 mm in the pre-TAD and TAD groups (all P TAD group and 48% of the TAD group. The correlation between the diameter and the length of the ascending aorta was r = 0.752; therefore, both parameters must be examined separately. A score considering both parameters identified 23.5% of pre-TAD patients, significantly more than the diameter alone, and 31.4% of ectasia aortas were elongated. Patients with ectatic (45-54 mm diameter) and elongated (≥120 mm) ascending aortas represent a high-risk subpopulation for TAD. © The Author(s) 2018. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Aortic Root Enlargement or Sutureless Valve Implantation?

Directory of Open Access Journals (Sweden)

Nikolaos G. Baikoussis

2016-11-01

Full Text Available Aortic valve replacement (AVR in patients with a small aortic annulus is a challenging issue. The importance of prosthesis–patient mismatch (PPM post aortic valve replacement (AVR is controversial but has to be avoided. Many studies support the fact that PPM has a negative impact on short and long term survival. In order to avoid PPM, aortic root enlargement may be performed. Alternatively and keeping in mind that often some comorbidities are present in old patients with small aortic root, the Perceval S suturelles valve implantation could be a perfect solution. The Perceval sutureless bioprosthesis provides reasonable hemodynamic performance avoiding the PPM and providing the maximum of aortic orifice area. We would like to see in the near future the role of the aortic root enlargement techniques in the era of surgical implantation of the sutureless valve (SAVR and the transcatheter valve implantation (TAVI.

Spectrum of ballooning instabilities in a stellarator

Energy Technology Data Exchange (ETDEWEB)

Cooper, W A [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP); Singleton, D B [Australian National Univ., ANU Supercomputing Facility, Canberra (Australia); Dewar, R L [Australian National Univ., Canberra, ACT (Australia). Research School of Physical Sciences

1995-08-01

The recent revival of interest in the application of the `ballooning formalism` to low-frequency plasma instabilities has prompted a comparison of the Wentzel-Brillouin-Kramers (WKB) ballooning approximation with an (in principle) exact normal mode calculation for a three-dimensional plasma equilibrium. Semiclassical quantization, using the ideal magnetohydrodynamic (MHD) ballooning eigenvalue to provide a local dispersion relation, is applied to a ten-field period stellarator test case. Excellent qualitative agreement, and good quantitative agreement is found with predictions from the TERPSICHORE code for toroidal mode numbers from 1 to 14 and radial mode numbers from 0 to 2. The continuum bands predicted from three-dimensional WKB theory are too narrow to resolve. (author) 3 figs., 24 refs.

Spectrum of ballooning instabilities in a stellarator

International Nuclear Information System (INIS)

Cooper, W.A.; Singleton, D.B.; Dewar, R.L.

1995-08-01

The recent revival of interest in the application of the 'ballooning formalism' to low-frequency plasma instabilities has prompted a comparison of the Wentzel-Brillouin-Kramers (WKB) ballooning approximation with an (in principle) exact normal mode calculation for a three-dimensional plasma equilibrium. Semiclassical quantization, using the ideal magnetohydrodynamic (MHD) ballooning eigenvalue to provide a local dispersion relation, is applied to a ten-field period stellarator test case. Excellent qualitative agreement, and good quantitative agreement is found with predictions from the TERPSICHORE code for toroidal mode numbers from 1 to 14 and radial mode numbers from 0 to 2. The continuum bands predicted from three-dimensional WKB theory are too narrow to resolve. (author) 3 figs., 24 refs

Molecular and cellular mechanisms of aortic stenosis.

Science.gov (United States)

Yetkin, Ertan; Waltenberger, Johannes

2009-06-12

Calcific aortic stenosis is the most common cause of aortic valve replacement in developed countries, and this condition increases in prevalence with advancing age. The fibrotic thickening and calcification are common eventual endpoint in both non-rheumatic calcific and rheumatic aortic stenoses. New observations in human aortic valves support the hypothesis that degenerative valvular aortic stenosis is the result of active bone formation in the aortic valve, which may be mediated through a process of osteoblast-like differentiation in these tissues. Additionally histopathologic evidence suggests that early lesions in aortic valves are not just a disease process secondary to aging, but an active cellular process that follows the classical "response to injury hypothesis" similar to the situation in atherosclerosis. Although there are similarities with the risk factor and as well as with the process of atherogenesis, not all the patients with coronary artery disease or atherosclerosis have calcific aortic stenosis. This review mainly focuses on the potential vascular and molecular mechanisms involved in the pathogenesis of aortic valve stenosis. Namely extracellular matrix remodeling, angiogenesis, inflammation, and eventually osteoblast-like differentiation resulting in bone formation have been shown to play a role in the pathogenesis of calcific aortic stenosis. Several mediators related to underlying mechanisms, including growth factors especially transforming growth factor-beta1 and vascular endothelial growth factors, angiogenesis, cathepsin enzymes, adhesion molecules, bone regulatory proteins and matrix metalloproteinases have been demonstrated, however the target to be attacked is not defined yet.

Application of thoracic endovascular aortic repair (TEVAR) in treating dwarfism with Stanford B aortic dissection

Science.gov (United States)

Qiu, Jian; Cai, Wenwu; Shu, Chang; Li, Ming; Xiong, Qinggen; Li, Quanming; Li, Xin

2018-01-01

Abstract Rationale: To apply thoracic endovascular aortic repair (TEVAR) to treat dwarfism complicated with Stanford B aortic dissection. Patient concerns: In this report, we presented a 63-year-old male patient of dwarfism complicated with Stanford B aortic dissection successfully treated with TEVAR. Diagnoses: He was diagnosed with dwarfism complicated with Stanford B aortic dissection. Interventions: After conservative treatment, the male patient underwent TEVAR at 1 week after hospitalization. After operation, he presented with numbness and weakness of his bilateral lower extremities, and these symptoms were significantly mitigated after effective treatment. At 1- and 3-week after TEVAR, the aorta status was maintained stable and restored. Outcomes: The patient obtained favorable clinical prognosis and was smoothly discharged. During subsequent follow-up, he remained physically stable. Lessons: TEVAR is probably an option for treating dwarfism complicated with Stanford B aortic dissection, which remains to be validated by subsequent studies with larger sample size. PMID:29703033

Angular (Gothic) aortic arch leads to enhanced systolic wave reflection, central aortic stiffness, and increased left ventricular mass late after aortic coarctation repair: evaluation with magnetic resonance flow mapping.

Science.gov (United States)

Ou, Phalla; Celermajer, David S; Raisky, Olivier; Jolivet, Odile; Buyens, Fanny; Herment, Alain; Sidi, Daniel; Bonnet, Damien; Mousseaux, Elie

2008-01-01

We sought to investigate the mechanism whereby a particular deformity of the aortic arch, an angulated Gothic shape, might lead to hypertension late after anatomically successful repair of aortic coarctation. Fifty-five normotensive patients with anatomically successful repair of aortic coarctation and either a Gothic (angulated) or a Romanesque (smooth and rounded) arch were studied with magnetic resonance angiography and flow mapping in both the ascending and descending aortas. Systolic waveforms, central aortic stiffness, and pulse velocity were measured. We hypothesized that arch angulation would result in enhanced systolic wave reflection with loss of energy across the aortic arch, as well as increased central aortic stiffness. Twenty patients were found to have a Gothic, and 35 a Romanesque, arch. Patients with a Gothic arch showed markedly augmented systolic wave reflection (12 +/- 6 vs 5 +/- 0.3 mL, P Gothic arch (5.6 +/- 1.1 vs 4.1 +/- 1 m/s, P Gothic aortic arch is associated with increased systolic wave reflection, as well as increased central aortic stiffness and left ventricular mass index. These findings explain (at least in part) the association between this pattern of arch geometry and late hypertension at rest and on exercise in subjects after coarctation repair.

A balloon-borne experiment to investigate the Martian magnetic field

Science.gov (United States)

Schwingenschuh, K.; Feldhofer, H.; Koren, W.; Jernej, I.; Stachel, M.; Riedler, W.; Slamanig, H.; Auster, H.-U.; Rustenbach, J.; Fornacon, H. K.; Schenk, H. J.; Hillenmaier, O.; Haerendel, G.; Yeroshenko, Ye.; Styashkin, V.; Zaroutzky, A.; Best, A.; Scholz, G.; Russell, C. T.; Means, J.; Pierce, D.; Luhmann, J. G.

1996-03-01

The Space Research Institute of the Austrian Academy, of Sciences (Graz, Austria) in cooperation with MPE (Berlin, Germany), GFZ Potsdam (Obs. Niemegk, Germany) IZMIRAN/IOFAN (Moscow, Russian) and IGPP/UCLA (Los Angeles, USA) is designing the magnetic field experiment MAGIBAL (MAGnetic field experiment aboard a martian BALloon) to investigate the magnetic field on the surface of Mars. The dual sensor fluxgate magnetometer is part of the MARS-98/MARS-TOGETHER balloon payload. During a ten days period the balloon will float over a distance of about 2000 km at altitudes between 0 and 4 km. Due to the limited power and telemetry allocation the magnetometer can transmit only one vector per ten seconds and spectral information in the frequency range from 2 - 25 Hz. The dynamic range is +/- 2000 nT. The main scientific objectives of the experiment are: • Determination of the magnetism of the Martian rocks • Investigation of the leakage of the solar wind induced magnetosphere using the correlation between orbiter and balloon observations • Measurement of the magnetic field profile between the orbiter and the surface of Mars during the descent phase of the balloon. Terrestrial test flights with a hot air balloon were performed in order to test the original MAGIBAL equipment under balloon flight conditions.

Usefulness of cutting balloon angioplasty for the treatment of congenital heart defects.

Science.gov (United States)

Kusa, Jacek; Mazurak, Magdalena; Skierska, Agnieszka; Szydlowski, Leslaw; Czesniewicz, Pawel; Manka, Lukasz

2018-01-01

Patients with complex congenital heart defects may have different hemodynamic prob-lems which require a variety of interventional procedures including angioplasty which involves using high-pressure balloons. After failure of conventional balloon angioplasty, cutting balloon angioplasty is the next treatment option available. The purpose of this study was to evaluate the safety and efficacy of cutting balloon angioplasty in children with different types of congenital heart defects. Cutting balloon angioplasty was performed in 28 children with different congenital heart defects. The indication for cutting balloon angioplasty was: pulmonary artery stenosis in 17 patients, creating or dilatation of interatrial communication in 10 patients, and stenosis of left subclavian artery in 1 patient. In the pulmonary arteries group there was a significant decrease in systolic blood pressure (SBP) in the proximal part of the artery from the average 74.33 ± 20.4 mm Hg to 55 ± 16.7 mm Hg (p cutting balloon angioplasty was performed after an unsuccessful classic Rashkind procedure. After cutting balloon angioplasty there was a significant widening of the interatrial communication. Cutting balloon angioplasty is a feasible and effective treatment option in different con-genital heart defects.

Aortic events in a nationwide Marfan syndrome cohort

DEFF Research Database (Denmark)

Groth, Kristian A; Krag, Kirstine Stochholm; Hove, Hanne

2017-01-01

BACKGROUND: Marfan syndrome is associated with morbidity and mortality due to aortic dilatation and dissection. Preventive aortic root replacement has been the standard treatment in Marfan syndrome patients with aortic dilatation. In this study, we present aortic event data from a nationwide Marfan...... syndrome cohort. METHOD: The nationwide cohort of Danish Marfan syndrome patients was established from the Danish National Patient Registry and the Cause of Death Register, where we retrieved information about aortic surgery and dissections. We associated aortic events with age, sex, and Marfan syndrome...

Balloon-Assisted Chemoembolization Using a Micro-Balloon Catheter Alongside a Microcatheter for a Hepatocellular Carcinoma with a Prominent Arterioportal Shunt: A Case Report

Energy Technology Data Exchange (ETDEWEB)

Hoshiai, Sodai, E-mail: hoshiai@sb4.so-net.ne.jp; Mori, Kensaku; Ishiguro, Toshitaka; Konishi, Takahiro; Uchikawa, Yoko [University of Tsukuba Hospital, Department of Diagnostic and Interventional Radiology (Japan); Fukuda, Kuniaki [University of Tsukuba Hospital, Department of Gastroenterology (Japan); Minami, Manabu [University of Tsukuba Hospital, Department of Diagnostic and Interventional Radiology (Japan)

2017-04-15

Although transcatheter arterial chemoembolization is one of the established treatments for hepatocellular carcinoma (HCC), it is difficult to treat HCCs with prominent arterioportal (AP) shunts because anticancer drugs and embolic materials migrate into the non-tumorous liver through the AP shunts and may cause liver infarction. We developed a novel method of balloon-assisted chemoembolization using a micro-balloon catheter alongside a microcatheter simultaneously inserted through a single 4.5-Fr guiding sheath, comprising proximal chemoembolization with distal arterial balloon occlusion. We applied this method to treat an HCC with a prominent distal AP shunt induced by previous proton beam therapy and achieved successful chemoembolization without non-tumorous liver infarction under temporal balloon occlusion of a distal AP shunt.

Ultrasonic delineation of aortic microstructure: The relative contribution of elastin and collagen to aortic elasticity

Science.gov (United States)

Marsh, Jon N.; Takiuchi, Shin; Lin, Shiow Jiuan; Lanza, Gregory M.; Wickline, Samuel A.

2004-05-01

Aortic elasticity is an important factor in hemodynamic health, and compromised aortic compliance affects not only arterial dynamics but also myocardial function. A variety of pathologic processes (e.g., diabetes, Marfan's syndrome, hypertension) can affect aortic elasticity by altering the microstructure and composition of the elastin and collagen fiber networks within the tunica media. Ultrasound tissue characterization techniques can be used to obtain direct measurements of the stiffness coefficients of aorta by measurement of the speed of sound in specific directions. In this study we sought to define the contributions of elastin and collagen to the mechanical properties of aortic media by measuring the magnitude and directional dependence of the speed of sound before and after selective isolation of either the collagen or elastin fiber matrix. Formalin-fixed porcine aortas were sectioned for insonification in the circumferential, longitudinal, or radial direction and examined using high-frequency (50 MHz) ultrasound microscopy. Isolation of the collagen or elastin fiber matrices was accomplished through treatment with NaOH or formic acid, respectively. The results suggest that elastin is the primary contributor to aortic medial stiffness in the unloaded state, and that there is relatively little anisotropy in the speed of sound or stiffness in the aortic wall.

Balloon sheaths for gastrointestinal guidance and access: a preliminary phantom study

International Nuclear Information System (INIS)

He, Xu; Shin, Ji Hoon; Kim, Hyo Cheol; Woo, Cheol Woong; Woo, Sung Ha; Choi, Won Chan; Kim, Jong Gyu; Lim, Jin Oh; Kim, Tae Hyung; Yoon, Chang Jin; Song, Ho Young; Kang, Wee Chang

2005-01-01

We wanted to evaluate the feasibility and usefulness of a newly designed balloon sheath for gastrointestinal guidance and access by conducting a phantom study. The newly designed balloon sheath consisted of an introducer sheath and a supporting balloon. A coil catheter was advanced over a guide wire into two gastroduodenal phantoms (one was with stricture and one was without stricture); group I was without a balloon sheath, group II was with a deflated balloon sheath, and groups III and IV were with an inflated balloon and with the balloon in the fundus and body, respectively. Each test was performed for 2 minutes and it was repeated 10 times in each group by two researchers, and the positions reached by the catheter tip were recorded. Both researchers had better performances with both phantoms in order of group IV, III, II and I. In group IV, both researchers advanced the catheter tip through the fourth duodenal segment in both the phantoms. In group I, however, the catheter tip never reached the third duodenal segment in both the phantoms by both the researchers. The numeric values for the four study groups were significantly different for both the phantoms (ρ < 0.001). A significant difference was also found between group III and IV for both phantoms (ρ < 0.001). The balloon sheath seems to be feasible for clinical use, and it has good clinical potential for gastrointestinal guidance and access, particularly when the inflated balloon is placed in the gastric body

Incidence, Prognostic Impact, and Predictive Factors of Readmission for Heart Failure After Transcatheter Aortic Valve Replacement.

Science.gov (United States)

Durand, Eric; Doutriaux, Maxime; Bettinger, Nicolas; Tron, Christophe; Fauvel, Charles; Bauer, Fabrice; Dacher, Jean-Nicolas; Bouhzam, Najime; Litzler, Pierre-Yves; Cribier, Alain; Eltchaninoff, Hélène

2017-12-11

The aim of this study was to assess the incidence, prognostic impact, and predictive factors of readmission for congestive heart failure (CHF) in patients with severe aortic stenosis treated by transcatheter aortic valve replacement (TAVR). TAVR is indicated in patients with severe symptomatic aortic stenosis in whom surgery is considered high risk or is contraindicated. Readmission for CHF after TAVR remains a challenge, and data on prognostic and predictive factors are lacking. All patients who underwent TAVR from January 2010 to December 2014 were included. Follow-up was achieved for at least 1 year and included clinical and echocardiographic data. Readmission for CHF was analyzed retrospectively. This study included 546 patients, 534 (97.8%) of whom were implanted with balloon-expandable valves preferentially via the transfemoral approach in 87.8% of cases. After 1 year, 285 patients (52.2%) had been readmitted at least once, 132 (24.1%) for CHF. Patients readmitted for CHF had an increased risk for death (p < 0.0001) and cardiac death (p < 0.0001) compared with those not readmitted for CHF. On multivariate analysis, aortic mean gradient (hazard ratio [HR]: 0.88; 95% confidence interval [CI]: 0.79 to 0.99; p = 0.03), post-procedural blood transfusion (HR: 2.27; 95% CI: 1.13 to 5.56; p = 0.009), severe post-procedural pulmonary hypertension (HR: 1.04; 95% CI: 1.00 to 1.07; p < 0.0001), and left atrial diameter (HR: 1.47; 95% CI: 1.08 to 2.01; p = 0.02) were independently associated with CHF readmission at 1 year. Readmission for CHF after TAVR was frequent and was strongly associated with 1-year mortality. Low gradient, persistent pulmonary hypertension, left atrial dilatation, and transfusions were predictive of readmission for CHF. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Hybrid treatment of penetrating aortic ulcer

International Nuclear Information System (INIS)

Lara, Juan Antonio Herrero; Martins-Romeo, Daniela de Araujo; Escudero, Carlos Caparros; Falcon, Maria del Carmen Prieto; Batista, Vinicius Bianchi; Vazquez, Rosa Maria Lepe

2015-01-01

Penetrating atherosclerotic aortic ulcer is a rare entity with poor prognosis in the setting of acute aortic syndrome. In the literature, cases like the present one, located in the aortic arch, starting with chest pain and evolving with dysphonia, are even rarer. The present report emphasizes the role played by computed tomography in the diagnosis of penetrating atherosclerotic ulcer as well as in the differentiation of this condition from other acute aortic syndromes. Additionally, the authors describe a new therapeutic approach represented by a hybrid endovascular surgical procedure for treatment of the disease. (author)

Hybrid treatment of penetrating aortic ulcer

Energy Technology Data Exchange (ETDEWEB)

Lara, Juan Antonio Herrero; Martins-Romeo, Daniela de Araujo; Escudero, Carlos Caparros; Falcon, Maria del Carmen Prieto; Batista, Vinicius Bianchi, E-mail: jaherrero5@hotmail.com [Unidade de Gestao Clinica (UGC) de Diagnostico por Imagem - Hosppital Universitario Virgen Macarena, Sevilha (Spain); Vazquez, Rosa Maria Lepe [Unit of Radiodiagnosis - Hospital Nuestra Senora de la Merced, Osuna, Sevilha (Spain)

2015-05-15

Penetrating atherosclerotic aortic ulcer is a rare entity with poor prognosis in the setting of acute aortic syndrome. In the literature, cases like the present one, located in the aortic arch, starting with chest pain and evolving with dysphonia, are even rarer. The present report emphasizes the role played by computed tomography in the diagnosis of penetrating atherosclerotic ulcer as well as in the differentiation of this condition from other acute aortic syndromes. Additionally, the authors describe a new therapeutic approach represented by a hybrid endovascular surgical procedure for treatment of the disease. (author)

Decreasing Compensatory Ability of Concentric Ventricular Hypertrophy in Aortic-Banded Rat Hearts

Directory of Open Access Journals (Sweden)

Alexandre Lewalle

2018-02-01

Full Text Available The cardiac system compensates for variations in physiological and pathophysiological conditions through a dynamic remodeling at the organ, tissue, and intracellular levels in order to maintain function. However, on longer time scales following the onset of ventricular pressure overload, such remodeling may begin to inhibit physiological function and ultimately lead to heart failure. This progression from compensatory to decompensatory behavior is poorly understood, in particular owing to the absence of a unified perspective of the concomitantly remodeling subsystems. To address this issue, the present study investigates the evolution of compensatory mechanisms, in response to overload, by integrating diffusion-tensor MRI, echocardiography, and intracellular and hemodynamic measurements within consistent computational simulations of aortic-banded rat hearts. This approach allows a comparison of the relative leverage of different cardiac properties (geometry, passive mechanical stiffness, fiber configuration, diastolic and peak calcium concentrations, calcium-binding affinity, and aortic impedance to affect cardiac contraction. Measurements indicate that, following aortic banding, an ejection fraction (EF of 75% was maintained, relative to control rats, despite significant remodeling of the left-ventricular wall thickness (increasing by ~90% over 4 weeks. Applying our framework, we identified the left-ventricular wall thickness (concentric hypertrophy and the intracellular calcium dynamics as playing the dominant roles in preserving EF acutely, whereas the significance of hypertrophy decreased subsequently. This trend suggests an increasing reliance on intracellular mechanisms (average increase ~50%, rather than on anatomical features (average decrease ~60%, to achieve compensation of pump function in the early phase of heart failure.

Stabilization of ballooning modes with sheared toroidal rotation

International Nuclear Information System (INIS)

Miller, R.L.; Waelbroeck, F.L.; Hassam, A.B.; Waltz, R.E.

1995-01-01

Stabilization of magnetohydrodynamic ballooning modes by sheared toroidal rotation is demonstrated using a shifted circle equilibrium model. A generalized ballooning mode representation is used to eliminate the fast Alfven wave, and an initial value code solves the resulting equations. The s-α diagram (magnetic shear versus pressure gradient) of ballooning mode theory is extended to include rotational shear. In the ballooning representation, the modes shift periodically along the field line to the next point of unfavorable curvature. The shift frequency (dΩ/dq, where Ω is the angular toroidal velocity and q is the safety factor) is proportional to the rotation shear and inversely proportional to the magnetic shear. Stability improves with increasing shift frequency and direct stable access to the second stability regime occurs when this frequency is approximately one-quarter to one-half the Alfven frequency, ω A =V A /qR. copyright 1995 American Institute of Physics

New-Onset Atrial Fibrillation After Surgical Aortic Valve Replacement and Transcatheter Aortic Valve Implantation

DEFF Research Database (Denmark)

Jørgensen, Troels Højsgaard; Thygesen, Julie Bjerre; Thyregod, Hans Gustav

2015-01-01

Surgical aortic valve replacement (SAVR) and, more recently, transcatheter aortic valve implantation (TAVI) have been shown to be the only treatments that can improve the natural cause of severe aortic valve stenosis. However, after SAVR and TAVI, the incidence of new-onset atrial fibrillation...... (NOAF) is 31%-64% and 4%-32%, respectively. NOAF is independently associated with adverse events such as stroke, death, and increased length of hospital stay. Increasing the knowledge of predisposing factors, optimal postprocedural monitoring, and prophylactic antiarrhythmic and antithrombotic therapy...

New-onset atrial fibrillation after surgical aortic valve replacement and transcatheter aortic valve implantation

DEFF Research Database (Denmark)

Jørgensen, Troels Højsgaard; Thygesen, Julie Bjerre; Thyregod, Hans Gustav

2015-01-01

Surgical aortic valve replacement (SAVR) and, more recently, transcatheter aortic valve implantation (TAVI) have been shown to be the only treatments that can improve the natural cause of severe aortic valve stenosis. However, after SAVR and TAVI, the incidence of new-onset atrial fibrillation...... (NOAF) is 31%-64% and 4%-32%, respectively. NOAF is independently associated with adverse events such as stroke, death, and increased length of hospital stay. Increasing the knowledge of predisposing factors, optimal postprocedural monitoring, and prophylactic antiarrhythmic and antithrombotic therapy...

Aortic valve ochronosis: a rare manifestation of alkaptonuria.

Science.gov (United States)

Steger, Christina Maria

2011-07-28

Alkaptonuric ochronosis is a heritable disorder of tyrosine metabolism, with various systemic abnormalities related to pigment deposition and degeneration of collagen and other tissues, including the heart and aorta. A 65-year-old woman with alkaptonuric ochronosis and a history of four joint replacements required aortic valve replacement for severe aortic stenosis. Operative findings included ochronosis of a partly calcified aortic valve and the aortic intima. The aortic valve was removed at surgery and histologically investigated. Light microscopic examination of the aortic valve revealed intracellular and extracellular deposits of ochronotic pigment and a chronic inflammatory infiltrate. Beside the case representation, the disease history, aetiology, pathogenesis, clinical presentation and treatment of aortic valve ochronosis are reviewed.

Abnormalities of aortic arch shape, central aortic flow dynamics, and distensibility predispose to hypertension after successful repair of aortic coarctation.

Science.gov (United States)

Donazzan, Luca; Crepaz, Robert; Stuefer, Josef; Stellin, Giovanni

2014-10-01

Systemic hypertension (HT) is a major long-term complication even after successful repair of aortic coarctation (CoA), and many factors are involved in this pathophysiology. To investigate the role of abnormalities in the aortic arch shape, central aortic flow dynamics, and distensibility in developing HT after successful repair of CoA. We selected a group of 26 normotensive patients (mean age 16.9±7.3 years, range 9-32 years) with anatomically successful repair of CoA among 140 patients regularly followed after repair of CoA and analyzed their last clinical and echocardiographic data. Bicycle exercise test and ambulatory blood pressure monitoring (ABPM) were also obtained. Mean age at surgical repair was 3.2±3.9 years (range 10 days-15 years); 12 patients underwent surgical correction during the first year of life. Repair of CoA was performed by end-to-end anastomosis (TT) in 23 patients (extended TT in 6 patients with arch hypoplasia), patch aortoplasty in 2, and subcalvian flap aortoplasty in 1. The postsurgical follow-up was 13.8±7.2 years (range 3.5-29.4 years). The shape of the aortic arch was defined by magnetic resonance imaging (MRI) on this global geometry (normal-gothic-crenel), ratio of the height-transverse diameter (A/T), percentage of residual stenosis, and growth index of the transverse arch segments. Flow mapping by phase-contrast imaging in the ascending and descending aorta was performed in order to measure the systolic waveforms and central aortic distensibility. Twenty normal age-matched patients submitted to the same MRI protocol were used as controls. Six patients were found to have a gothic and 20 a normal aortic arch shape. Patients with gothic aortic arch shape had an increased A/T ratio (0.80±0.07 vs 0.58±0.05, P135 mm Hg on ABPM were higher in the gothic than in the normal arch group. There was a correlation between nocturnal SBP, 24 hours pulse pressure on ABPM in the whole group, and different MRI variables (A/T, distensibility of

2015 SCAI/ACC/HFSA/STS Clinical Expert Consensus Statement on the Use of Percutaneous Mechanical Circulatory Support Devices in Cardiovascular Care (Endorsed by the American Heart Association, the Cardiological Society of India, and Sociedad Latino Americana de Cardiologia Intervencion; Affirmation of Value by the Canadian Association of Interventional Cardiology-Association Canadienne de Cardiologie D'intervention).

Science.gov (United States)

Rihal, Charanjit S; Naidu, Srihari S; Givertz, Michael M; Szeto, Wilson Y; Burke, James A; Kapur, Navin K; Kern, Morton; Garratt, Kirk N; Goldstein, James A; Dimas, Vivian; Tu, Thomas

2015-06-01

Although historically the intra-aortic balloon pump has been the only mechanical circulatory support device available to clinicians, a number of new devices have become commercially available and have entered clinical practice. These include axial flow pumps, such as Impella®; left atrial to femoral artery bypass pumps, specifically the TandemHeart; and new devices for institution of extracorporeal membrane oxygenation. These devices differ significantly in their hemodynamic effects, insertion, monitoring, and clinical applicability. This document reviews the physiologic impact on the circulation of these devices and their use in specific clinical situations. These situations include patients undergoing high-risk percutaneous coronary intervention, those presenting with cardiogenic shock, and acute decompensated heart failure. Specialized uses for right-sided support and in pediatric populations are discussed and the clinical utility of mechanical circulatory support devices is reviewed, as are the American College of Cardiology/American Heart Association clinical practice guidelines. © 2015 by The Society for Cardiovascular Angiography and Interventions, The American College of Cardiology Foundation, The Heart Failure Society of America, and The Society for Thoracic Surgery.

Ozone profiles from tethered balloon measurements in an urban plume experiment

Science.gov (United States)

Youngbluth, O., Jr.; Storey, R. W.; Clendenin, C. G.; Jones, S.; Leighty, B.

1981-01-01

NASA Langley Research Center used two tethered balloon systems to measure ozone in the general area of Norfolk, Va. The large balloon system which has an altitude range of 1,500 meters was located at Wallops Island, Va., and the smaller balloon which has an altitude range of 900 meters was located at Chesapeake, Va. Each balloon system measured ozone, temperature, humidity, wind speed, and wind direction from ground to its maximum altitude. From these measurements and from the location of the balloon sites, areas of ozone generation and ozone transport may be inferred. The measurements which were taken during August 1979 are discussed as well as the measurement techniques.

Complex Coronary Interventions with the Novel Mozec™ CTO Balloon: The MOZART Registry.

Science.gov (United States)

Lupi, Alessandro; Rognoni, Andrea; Schaffer, Alon; Secco, Gioel G; Bongo, Angelo S

2015-01-01

Mozec™ CTO is a novel semicompliant rapid-exchange PTCA balloon catheter with specific features dedicated to treat complex coronary lesions like chronic total occlusions (CTOs). However, no data have been reported about the performance of this device in an all-comers population with complex coronary lesions. We evaluated the safety and success rate of Mozec™ CTO balloon in 41 consecutive patients with chronic stable angina and complex coronary lesions (15 severe calcified coronary stenoses, 15 bifurcation lesions with planned two-stent intervention, and 11 CTOs). Safety was assessed reporting the balloon burst rate after inflation exceeding the rated burst pressure (RBP) according to the manufacturer's reference table. Success was defined as the possibility to advance the device further the target lesion. The Mozec™ CTO balloon showed an excellent performance with a 93.3% success in crossing tight and severely calcified lesions (14/15 pts), a 93.3% success in engaging jailed side branches after stent deployment across bifurcations (14/15 pts), and a 90.9% success in crossing CTO lesions (10/11 pts). The burst rate at RBP of the Mozec™ CTO balloon was 6.7% (1/15 balloons) in the tight and severely calcified lesions, 6.7% (1/15 balloons) when dilating jailed vessels, and 9.1% (1/11 balloons) in CTOs. The novel Mozec™ CTO balloon dilatation catheter showed promising results when employed to treat complex lesions in an all-comers population. Further studies should clarify if this kind of balloon might reduce the need of more costly devices like over-the-wire balloons and microcatheters for complex lesions treatment.

Aortic stiffness and diameter predict progressive aortic dilatation in patients with Marfan syndrome

NARCIS (Netherlands)

Nollen, Gijs J.; Groenink, Maarten; Tijssen, Jan G. P.; van der Wall, Ernst E.; Mulder, Barbara J. M.

2004-01-01

Aim Patients with Marfan syndrome may develop dissection due to progressive dilatation in the entire aorta, which is not always predictable by mere anatomic assessment of the aortic diameter, especially of the descending aorta. The aim of this study was to identify the predictive value of aortic

Balloon-Borne Infrasound Detection of Energetic Bolide Events

Science.gov (United States)

Young, Eliot F.; Ballard, Courtney; Klein, Viliam; Bowman, Daniel; Boslough, Mark

2016-10-01

Infrasound is usually defined as sound waves below 20 Hz, the nominal limit of human hearing. Infrasound waves propagate over vast distances through the Earth's atmosphere: the CTBTO (Comprehensive Nuclear-Test-Ban Treaty Organization) has 48 installed infrasound-sensing stations around the world to detect nuclear detonations and other disturbances. In February 2013, several CTBTO infrasound stations detected infrasound signals from a large bolide that exploded over Chelyabinsk, Russia. Some stations recorded signals that had circumnavigated the Earth, over a day after the original event. The goal of this project is to improve upon the sensitivity of the CTBTO network by putting microphones on small, long-duration super-pressure balloons, with the overarching goal of studying the small end of the NEO population by using the Earth's atmosphere as a witness plate.A balloon-borne infrasound sensor is expected to have two advantages over ground-based stations: a lack of wind noise and a concentration of infrasound energy in the "stratospheric duct" between roughly 5 - 50 km altitude. To test these advantages, we have built a small balloon payload with five calibrated microphones. We plan to fly this payload on a NASA high-altitude balloon from Ft Sumner, NM in August 2016. We have arranged for three large explosions to take place in Socorro, NM while the balloon is aloft to assess the sensitivity of balloon-borne vs. ground-based infrasound sensors. We will report on the results from this test flight and the prospects for detecting/characterizing small bolides in the stratosphere.

Aortic events in a nationwide Marfan syndrome cohort.

Science.gov (United States)

Groth, Kristian A; Stochholm, Kirstine; Hove, Hanne; Kyhl, Kasper; Gregersen, Pernille A; Vejlstrup, Niels; Østergaard, John R; Gravholt, Claus H; Andersen, Niels H

2017-02-01

Marfan syndrome is associated with morbidity and mortality due to aortic dilatation and dissection. Preventive aortic root replacement has been the standard treatment in Marfan syndrome patients with aortic dilatation. In this study, we present aortic event data from a nationwide Marfan syndrome cohort. The nationwide cohort of Danish Marfan syndrome patients was established from the Danish National Patient Registry and the Cause of Death Register, where we retrieved information about aortic surgery and dissections. We associated aortic events with age, sex, and Marfan syndrome diagnosis prior or after the first aortic event. From the total cohort of 412 patients, 150 (36.4 %) had an aortic event. Fifty percent were event free at age 49.6. Eighty patients (53.3 %) had prophylactic surgery and seventy patients (46.7 %) a dissection. The yearly event rate was 0.02 events/year/patient in the period 1994-2014. Male patients had a significant higher risk of an aortic event at a younger age with a hazard ratio of 1.75 (CI 1.26-2.42, p = 0.001) compared with women. Fifty-three patients (12.9 %) were diagnosed with MFS after their first aortic event which primarily was aortic dissection [n = 44 (83.0 %)]. More than a third of MFS patients experienced an aortic event and male patients had significantly more aortic events than females. More than half of the total number of dissections was in patients undiagnosed with MFS at the time of their event. This emphasizes that diagnosing MFS is lifesaving and improves mortality risk by reducing the risk of aorta dissection.

Extending the golden hour: Partial resuscitative endovascular balloon occlusion of the aorta in a highly lethal swine liver injury model.

Science.gov (United States)

Russo, Rachel M; Williams, Timothy K; Grayson, John Kevin; Lamb, Christopher M; Cannon, Jeremy W; Clement, Nathan F; Galante, Joseph M; Neff, Lucas P

2016-03-01

Combat-injured patients may require rapid and sustained support during transport; however, the prolonged aortic occlusion produced by conventional resuscitative endovascular balloon occlusion of the aorta (REBOA) may lead to substantial morbidity. Partial REBOA (P-REBOA) may permit longer periods of occlusion by allowing some degree of distal perfusion. However, the ability of this procedure to limit exsanguination is unclear. We evaluated the impact of P-REBOA on immediate survival and ongoing hemorrhage in a highly lethal swine liver injury model. Fifteen Yorkshire-cross swine were anesthetized, instrumented, splenectomized, and subjected to rapid 10% total blood loss followed by 30% liver amputation. Coagulopathy was created through colloid hemodilution. Randomized swine received no intervention (control), P-REBOA, or complete REBOA (C-REBOA). Central mean arterial pressure (cMAP), carotid blood flow, and blood loss were recorded. Balloons remained inflated in the P-REBOA and C-REBOA groups for 90 minutes followed by graded deflation. The study ended at 180 minutes from onset of hemorrhage or death of the animal. Survival analysis was performed, and data were analyzed using repeated-measures analysis of variance with post hoc pairwise comparisons. Mean survival times in the control, P-REBOA, and C-REBOA groups were, 25 ± 21, 86 ± 40, and 163 ± 20 minutes, respectively (p golden hour while maintaining cMAP and carotid flow at physiologic levels.

Selective Aortic Arch and Root Replacement in Repair of Acute Type A Aortic Dissection.

Science.gov (United States)

Fleischman, Fernando; Elsayed, Ramsey S; Cohen, Robbin G; Tatum, James M; Kumar, S Ram; Kazerouni, Kayvan; Mack, Wendy J; Barr, Mark L; Cunningham, Mark J; Hackmann, Amy E; Baker, Craig J; Starnes, Vaughn A; Bowdish, Michael E

2018-02-01

Controversy exists regarding the optimal extent of repair for type A aortic dissection. Our approach is to replace the ascending aorta, and only replace the aortic root or arch when intimal tears are present in those areas. We examined intermediate outcomes with this approach to acute type A aortic dissection repair. Between March 2005 and October 2016, 195 patients underwent repair of acute type A aortic dissection. Repair was categorized by site of proximal and distal anastomosis and extent of repair. Mean follow-up was 31.0 ± 30.9 months. Kaplan-Meier analysis was used to assess survival. Multiple variable Cox proportional hazards modeling was utilized to identify factors associated with overall mortality. Overall survival was 85.1%, 83.9%, 79.1%, and 74.4% at 6, 12, 36, and 60 months, respectively. Eight patients required reintervention. The cumulative incidence of aortic reintervention at 1 year with death as a competing outcome was 3.95%. Multiple variable regression analysis identified factors such as age, preoperative renal failure, concomitant thoracic endograft, postoperative myocardial infarction and sepsis, and need for extracorporeal membrane oxygenation as predictive of overall mortality. Neither proximal or distal extent of repair, nor need for reintervention affected overall survival (proximal: hazard ratio 1.63, 95% confidence interval: 0.75 to 3.51, p = 0.22; distal: hazard ratio 1.12, 95% confidence interval: 0.43 to 2.97, p = 0.81; reintervention: hazard ratio 0.03, 95% confidence interval: 0.002 to 0.490, p < 0.01). A selective approach to root and arch repair in acute type A aortic dissection is safe. If aortic reintervention is needed, survival does not appear to be affected. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Design Evolution and Methodology for Pumpkin Super-Pressure Balloons

Science.gov (United States)

Farley, Rodger

The NASA Ultra Long Duration Balloon (ULDB) program has had many technical development issues discovered and solved along its road to success as a new vehicle. It has the promise of being a sub-satellite, a means to launch up to 2700 kg to 33.5 km altitude for 100 days from a comfortable mid-latitude launch point. Current high-lift long duration ballooning is accomplished out of Antarctica with zero-pressure balloons, which cannot cope with the rigors of diurnal cycles. The ULDB design is still evolving, the product of intense analytical effort, scaled testing, improved manufacturing, and engineering intuition. The past technical problems, in particular the s-cleft deformation, their solutions, future challenges, and the methodology of pumpkin balloon design will generally be described.

A first-in-man study of the Reitan catheter pump for circulatory support in patients undergoing high-risk percutaneous coronary intervention.

Science.gov (United States)

Smith, Elliot J; Reitan, Oyvind; Keeble, Thomas; Dixon, Kerry; Rothman, Martin T

2009-06-01

To investigate the safety of a novel percutaneous circulatory support device during high-risk percutaneous coronary intervention (PCI). The Reitan catheter pump (RCP) consists of a catheter-mounted pump-head with a foldable propeller and surrounding cage. Positioned in the descending aorta the pump creates a pressure gradient, reducing afterload and enhancing organ perfusion. Ten consecutive patients requiring circulatory support underwent PCI; mean age 71 +/- 9; LVEF 34% +/- 11%; jeopardy score 8 +/- 2.3. The RCP was inserted via the femoral artery. Hemostasis was achieved using Perclose sutures. PCI was performed via the radial artery. Outcomes included in-hospital death, MI, stroke, and vascular injury. Hemoglobin (Hb), free plasma Hb (fHb), platelets, and creatinine (cre) were measured pre PCI and post RCP removal. The pump was inserted and operated successfully in 9/10 cases (median 79 min). Propeller rotation at 10,444 +/- 1,424 rpm maintained an aortic gradient of 9.8 +/- 2 mm Hg. Although fHb increased, there was no significant hemolysis (4.7 +/- 2.4 mg/dl pre vs. 11.9 +/- 10.5 post, P = 0.04, reference 20 mg/dl). Platelets were unchanged (pre 257 +/- 74 x 10(9) vs. 245 +/- 63, P = NS). Renal function improved (cre pre 110 +/- 27 micromol/l vs. 99 +/- 28, P = 0.004). The RCP was not used in one patient following femoral introducer sheath related aortic dissection. All PCI procedures were successful with no deaths or strokes, one MI, and no vascular complications following pump removal. The RCP can be used safely in high-risk PCI patients. This device may be an alternative to other percutaneous systems when substantial cardiac support is needed. (c) 2009 Wiley-Liss, Inc.

The role of scientific ballooning for exploration of the magnetosphere

International Nuclear Information System (INIS)

Block, L.P.; Lazutin, L.L.; Riedler, W.

1984-11-01

The magnetosphere is explored in situ by satellites, but measurements near the low altitude magnetospheric boundary by rockets, balloons and groundbased instruments play a very significant role. The geomagnetic field provides a frame with anisotropic wave and particle propagation effects, enabling remote sensing of the distant magnetosphere by means of balloon-borne and groundbased instruments. Examples will be given of successful studies, with coordinated satellite and balloon observations, of substorm, pulsation and other phenomena propagating both along and across the geomagnetic field. Continued efforts with sophisticated balloon-borne instrumentations should contribute substantially to our understanding of magnetospheric physics. (Author)

Montgolfiere balloon missions from Mars and Titan

Science.gov (United States)

Jones, Jack A.

2005-01-01

Montgolfieres, which are balloons that are filled with heated ambient atmospheric gas, appear promising for the exploration of Mars as well as of Saturn's moon, Titan. On Earth, Montgolfieres are also known as 'hot air balloons'. Commercial versions are typically heated by burning propane, although a number of radiant and solar-heated Montgolfieres have been flown on earth by CNES.

Location and data collection for long stratospheric balloon flights

Science.gov (United States)

Malaterre, P.

Stratospheric balloons capable of taking a 30 kg scientific payload to an altitude of 22 to 30 km for 1 month or more were developed. In-flight experiments were used to qualify the designs of a pumpkin shaped superpressure balloon and an infrared hot air balloon. Tracking of the flights (location and transmission of the parameters measured on board) was achieved using a telemetry gondola including an ARGOS beacon adapted for operation in the low temperatures encountered.

Euso-Balloon: A pathfinder mission for the JEM-EUSO experiment

Energy Technology Data Exchange (ETDEWEB)

Osteria, Giuseppe, E-mail: osteria@na.infn.it [Istituto Nazionale di Fisica Nucleare Sezione di Napoli, Naples (Italy); Scotti, Valentina [Istituto Nazionale di Fisica Nucleare Sezione di Napoli, Naples (Italy); Università di Napoli Federico II, Dipartimento di Fisica, Naples (Italy)

2013-12-21

EUSO-Balloon is a pathfinder mission for JEM-EUSO, the near-UV telescope proposed to be installed on board the ISS in 2017. The main objective of this pathfinder mission is to perform a full scale end-to-end test of all the key technologies and instrumentation of JEM-EUSO detectors and to prove the entire detection chain. EUSO-Balloon will measure the atmospheric and terrestrial UV background components, in different observational modes, fundamental for the development of the simulations. Through a series of flights performed by the French Space Agency CNES, EUSO-Balloon also has the potential to detect Extensive Air Showers (EAS) from above. EUSO-Balloon will be mounted in an unpressurized gondola of a stratospheric balloon. We will describe the instrument and the electronic system which performs instrument control and data management in such a critical environment.

Dissection of Retroesophageal Aortic Diverticulum and Descending Aorta in a Patient with Right Aortic Arch: Magnetic Resonance Demonstration

International Nuclear Information System (INIS)

Ko, S.-F.; Ng, S.-H.; Fu, Morgan; Lo, P.-H.; Cheng, Y.-F.; Lee, T.-Y.

1996-01-01

An acute aortic dissection involved the retroesophageal aortic diverticulum (RAD) and descending thoracic aorta in a patient with right aortic arch. The RAD, which was separated into false and true lumens by an intimal flap-the classic diagnostic sign of aortic dissection-was overlooked on transesophageal echocardiography and computed tomography but was clearly depicted on magnetic resonance imaging (MRI). It was found that MRI can delineate the anatomy of a congenital arch anomaly complicated by great vessels disease

78 FR 18533 - Airworthiness Directives; Lindstrand Hot Air Balloons Ltd Appliances

Science.gov (United States)

2013-03-27

... Airworthiness Directives; Lindstrand Hot Air Balloons Ltd Appliances AGENCY: Federal Aviation Administration... Hot Air Balloons Ltd female ACME threaded hose connectors, part numbers HS6139 and HS6144, installed... follows: * * * * * (c) Applicability This AD applies to Lindstrand Hot Air Balloons Ltd female ACME...

77 FR 64763 - Airworthiness Directives; Lindstrand Hot Air Balloons Ltd Appliances

Science.gov (United States)

2012-10-23

... Airworthiness Directives; Lindstrand Hot Air Balloons Ltd Appliances AGENCY: Federal Aviation Administration... propose to adopt a new airworthiness directive (AD) for certain Lindstrand Hot Air Balloons Ltd female... identified in this proposed AD, contact Lindstrand Hot Air Balloons Ltd., Maesbury Road, Oswestry, Shropshire...