On pressure: volume relations in hemodialysis

NARCIS (Netherlands)

E.H.Y. Ie (Eric)

2005-01-01

textabstractChapter 1 is a brief introduction to several aspects of cardiovascular pressure-volume relations in dialysis patients. The aims of the thesis are presented. In Chapter 2, an overview is presented of circulatory physiology in hemodialysis (HD) patients. Volume withdrawal by

[Development of an automatic pneumatic tourniquet system that determines pressures in synchrony with systolic blood pressure].

Science.gov (United States)

Liu, Hongyun; Li, Kaiyuan; Zhang, Zhengbo; Guo, Junyan; Wang, Weidong

2012-11-01

The correlation coefficients between arterial occlusion pressure and systolic blood pressure, diastolic blood pressure, limb circumference, body mass etc were obtained through healthy volunteer experiments, in which tourniquet were applied on upper/lower extremities. The prediction equations were derived from the data of experiments by multiple regression analysis. Based on the microprocessor C8051F340, a new pneumatic tourniquet system that can determine tourniquet pressure in synchrony with systolic blood pressure was developed and verified the function and stability of designed system. Results showed that the pneumatic tourniquet which automatically adjusts occlusion pressure in accordance with systolic blood pressure could stop the flow of blood to get a bloodless field.

Aircraft vibration and other factors related to high systolic blood pressure in Indonesian Air Force pilots

Directory of Open Access Journals (Sweden)

Minarma Siagian

2013-05-01

Full Text Available AbstrakLatar belakang: Penerbangan dapat berdampak pada sistem kardiovaskular manusia. Penerbang terpajan antara lain pada bising dan vibrasi pesawat. Penelitian bertujuan untuk mengetahui pengaruh beberapa faktor penerbangan pada tekanan darah sistolik.Metode: Penelitian nested case-control dilakukan pada penerbang Angkatan Udara Republik Indonesia yang melakukan pemeriksaan fisik tahunan di Lembaga Kesehatan Penerbangan dan Ruang Angkasa (LAKESPRA Saryanto tahun 2003–2008. Data yang diperoleh dari rekam medik berupa umur, jumlah jam terbang, jenis pesawat, kadar glukosa puasa dan kadar kholesterol darah, lingkaran pinggang, tinggi dan berat badan, tinggi badan, serta tekanan darah.Hasil: Dari 336 penerbang, terdapat 16 penerbanga dengan tekanan sistolik ³ 140 mmHg. Penerbang dengan rata-rata jam penerbangan 300-622 jam per tahun dibandingkan dengan 29-299 jam per tahun mempunyai risiko peningkatan tekanan darah sistolik tinggi sebesarf 5 kali [rasio odds suaian (ORa = 5,05, 95% interval kepercayaan (CI = 0,88 -23,30, P = 0,070]. Menurut jam terbang total, mereka yang memiliki 1.401-1,1125 jam dibandingkan 147-1.400 jam berisiko 3,6 kali mengalami tekanan darah sistolik tinggi (ORa = 3,58, 95% CI = 1,24-10,38. Selain itu, mereka dengan denyut nadi istirahat tinggi dibandingkan dengan denyut nadi normal istirahat memiliki 2,4 kali mengalami tekanan darah sistolik tinggi (ORa = 2,37, CI = 0,74-7,50 95, P = 0,147].Kesimpulan: Vibrasi pesawat terbang tinggi, rata-rata jam terbang per tahun tinggi, dan frekuensi nadi istirahat yang tinggi meningkatkan risiko tekanan sistolik tinggi.Kata kunci:tekanan darah sistolik, vibrasi pesawat terbang, frekuensi nadi istirahat, pilotAbstractBackground:Flight may affect the human cardiovascular system. Pilots are exposed among others to aircraft noise and vibration. This study aimed to investigate the effects of aircraft flight on systolic blood pressure.Methods:A nested case-control study was conducted on

Reducing maternal mortality: Systolic blood pressure

African Journals Online (AJOL)

2006-03-21

Mar 21, 2006 ... While deaths due to fluid overload have ... of better fluid balance management, we have made .... systolic blood pressure plays a significant role in the .... one looks at the work of Martin et al.5 ... Promoting Healthy Life.

Left ventricular volume during supine exercise: importance of myocardial scar in patients with coronary heart disease

International Nuclear Information System (INIS)

Mann, D.L.; Scharf, J.; Ahnve, S.; Gilpin, E.

1987-01-01

Existing studies suggest that exercise-induced ischemia produces an increase in left ventricular end-diastolic volume; however, all of these studies have included patients with previous myocardial infarction. To test whether the end-diastolic volume response to exercise is related to the extent of myocardial scar, the results of gated radionuclide supine exercise tests performed on 130 subjects were reviewed. The patient group comprised 130 subjects were reviewed. The patient group comprised 130 men aged 35 to 65 years (mean +/- SD 52 +/- 5) with documented coronary heart disease. The extent of myocardial ischemia and scar formation was assessed by stress electrocardiography and thallium-201 scintigraphy. Patients were classified into three groups on the basis of left ventricular end-diastolic volume response at peak exercise: group 1 (n = 72) had an increase of end-diastolic volume greater than 10%, group 2 (n = 41) had a change in end-diastolic volume less than 10% and group 3 (n = 17) had a decrease in end-diastolic volume greater than 10% (n = 17). At rest there was no significant difference among groups in heart rate, systolic blood pressure, end-diastolic (EDVrest) or end-systolic volumes or ejection fraction (p greater than 0.05); however, at peak exercise the end-systolic volume response was significantly greater for group 1 (p less than 0.002)

Diastolic pressure underestimates age-related hemodynamic impairment.

Science.gov (United States)

Galarza, C R; Alfie, J; Waisman, G D; Mayorga, L M; Cámera, L A; del Río, M; Vasvari, F; Limansky, R; Farías, J; Tessler, J; Cámera, M I

1997-10-01

It has been hypothesized that as large arteries become more rigid with age, the pattern of hypertension changes from diastolic to systolic. Thus, diastolic blood pressure (DBP) may lose its ability to reflect the increase in vascular resistance with age. To assess this, we studied the age-related changes in blood pressure pattern and its steady-state and pulsatile determinants. We performed an epidemiological analysis based on a national survey of 10,462 subjects from Argentina. A hemodynamic analysis (impedance cardiography) was then carried out in 636 consecutive hypertensive patients (age, 25 to 74 years). Whereas the rate of increment in the prevalence of mild to moderate hypertension (MMH) reached a plateau after the sixth decade, isolated and borderline systolic forms of hypertension began a steep and sustained rise. Among patients with MMH, DBP remained stable from the third to the seventh decade, whereas SBP maintained a sustained increase. Despite similar DBP, the systemic vascular resistance index increased 47% (P<.01) and the cardiac index decreased 27% (P<.01), whereas the ratio of stroke volume to pulse pressure, an index of arterial compliance, decreased 45% (P<.01). However, there were no significant differences between older patients with MMH and those with isolated systolic hypertension in the level of SBP, vascular resistance, stroke volume, and cardiac index. Compared with age-matched normotensive control subjects, the ratio of stroke volume to pulse pressure was much more reduced in isolated systolic hypertension (48%) than in MMH (30%). In summary, the present study, carried out in a large sample of hypertensive subjects with a wide age range, showed a simultaneous impairment in vascular resistance and arterial compliance associated with aging in different patterns of hypertension. The magnitude of these changes, with opposite effects on DBP but additive effects on SBP, suggests that a hemodynamic mechanism could determine the transition in the

Microalbuminuria in patients with non-insulin-dependent diabetes mellitus relates to nocturnal systolic blood pressure.

LENUS (Irish Health Repository)

Mitchell, T H

2012-02-03

PURPOSE: Microalbuminuria predicts early mortality in non-insulin-dependent-diabetes mellitus patients (NIDDM). Our objective in the present study was to compare and assess the relationship between 24-hour, day and nocturnal ambulatory blood pressure (BP) and urinary albumin excretion rate (UAE) in microalbuminuric and normoalbuminuric NIDDM and in normal control subjects. PATIENTS AND METHODS: In the present cross-sectional study, 24 hour ambulatory BP (daytime BP and nocturnal BP) and HbA1c were compared in microalbuminuric (n = 10) and nonmicroalbuminuric NIDDM patients (n = 10) and in nondiabetic controls (n = 9). None of the patients were taking antihypertensive agents. RESULTS: In the microlbuminuric group, whereas 24 hour and daytime systolic BP differed significantly from control values (P < 0.025 and P < 0.05 respectively), there was no difference between diabetic groups. However, nocturnal systolic BP in the microalbuminuric group was significantly higher than in the normoalbuminuric diabetic patients (139 vs. 125) (P < 0.05) and a significant difference was also found between the NIDDM patients and the control group (139, 125 vs. 114) (P < 0.025). In multiple regression analysis, only nocturnal systolic BP showed a significant relationship with UAE (P < 0.05). CONCLUSIONS: We suggest that the higher nocturnal systolic blood pressure seen in our microalbuminuric NIDDM patients may contribute to the increased morbidity in this group.

Central Pressure Appraisal: Clinical Validation of a Subject-Specific Mathematical Model.

Directory of Open Access Journals (Sweden)

Francesco Tosello

Full Text Available Current evidence suggests that aortic blood pressure has a superior prognostic value with respect to brachial pressure for cardiovascular events, but direct measurement is not feasible in daily clinical practice.The aim of the present study is the clinical validation of a multiscale mathematical model for non-invasive appraisal of central blood pressure from subject-specific characteristics.A total of 51 young male were selected for the present study. Aortic systolic and diastolic pressure were estimated with a mathematical model and were compared to the most-used non-invasive validated technique (SphygmoCor device, AtCor Medical, Australia. SphygmoCor was calibrated through diastolic and systolic brachial pressure obtained with a sphygmomanometer, while model inputs consist of brachial pressure, height, weight, age, left-ventricular end-systolic and end-diastolic volumes, and data from a pulse wave velocity study.Model-estimated systolic and diastolic central blood pressures resulted to be significantly related to SphygmoCor-assessed central systolic (r = 0.65 p <0.0001 and diastolic (r = 0.84 p<0.0001 blood pressures. The model showed a significant overestimation of systolic pressure (+7.8 (-2.2;14 mmHg, p = 0.0003 and a significant underestimation of diastolic values (-3.2 (-7.5;1.6, p = 0.004, which imply a significant overestimation of central pulse pressure. Interestingly, model prediction errors mirror the mean errors reported in large meta-analysis characterizing the use of the SphygmoCor when non-invasive calibration is performed.In conclusion, multi-scale mathematical model predictions result to be significantly related to SphygmoCor ones. Model-predicted systolic and diastolic aortic pressure resulted in difference of less than 10 mmHg in the 51% and 84% of the subjects, respectively, when compared with SphygmoCor-obtained pressures.

Inter-arm systolic blood pressure differences, relations with future vascular events and mortality in patients with and without manifest vascular disease

NARCIS (Netherlands)

Kranenburg, Guido; Spiering, Wilko; de Jong, Pim A.; Kappelle, L. Jaap; de Borst, Gert Jan; Cramer, Maarten J.; Visseren, Frank L.J.; Aboyans, Victor; Westerink, Jan

2017-01-01

Background Inter-arm systolic blood pressure difference (SBPD) is an easily obtained patient characteristic which relates to vascular disease. We aimed to identify determinants of large inter-arm SBPD and to investigate the relation between inter-arm SBPD and vascular events in patients with and

Systolic Blood Pressure Accuracy Enhancement in the Electronic Palpation Method Using Pulse Waveform

National Research Council Canada - National Science Library

Sorvoja, H

2001-01-01

.... Systolic pressure errors were defined and correlations with other specific values, like pressure rise time, pulse wave velocity, systolic pressure, augmentation, arm circumference and body mass index were calculated...

Contributions of social context to blood pressure: findings from a multilevel analysis of social capital and systolic blood pressure.

Science.gov (United States)

Hamano, Tsuyoshi; Fujisawa, Yoshikazu; Yamasaki, Masayuki; Ito, Katsuhisa; Nabika, Toru; Shiwaku, Kuninori

2011-06-01

In recent years, few studies have quantified the effect of residential context on blood pressure. Although these studies have emphasized the importance of socioeconomic influences such as education or poverty levels, the association between the features of social structure such as social capital and blood pressure remain unclear. Therefore, we investigated whether social capital was associated with systolic blood pressure after controlling for individual potential confounders. We analyzed data from the Shimane Study conducted from 2006 to 2008 in rural mountainous regions of Japan. After excluding the missing data and data of participants taking hypertension medication, we conducted a multilevel analysis of the data for 335 individuals nested within 30 postcode sectors. Systolic blood pressure increased with increasing age and body mass index. We also found that a higher systolic blood pressure was observed among smokers and those taking medication for diabetes. Regarding the contextual effects of social capital, systolic blood pressure increased with an increasing proportion of lack of fairness, after adjustment for individual confounders. To the best of our knowledge, this study is the first to investigate the association between social capital and systolic blood pressure by using a multilevel methodological framework. Surprisingly, we found that lack of fairness had a strong effect on systolic blood pressure. However, we could not find any significant associations between other items of social capital and systolic blood pressure. Further studies are needed to clarify the mechanism by which lack of fairness may have an effect on systolic blood pressure.

Effects of positive end-expiratory pressure on renal function.

Science.gov (United States)

Järnberg, P O; de Villota, E D; Eklund, J; Granberg, P O

1978-01-01

The effects were studied positive end-expiratory pressure (PEEP) on renal function in eight patients with acute respiratory failure, requiring mechanical ventilation. On application of PEEP + 10 cm H2O, central venous pressure increased, systolic blood pressure decreased, urine flow and PAH-clearance were reduced, while inulin clearance remained stable. There was a marked increase in fractional sodium reabsorption and a concurrent decrease in fractional osmolal excretion. Fractional free-water clearance and the ratio UOsm/POsm did change.

The systolic blood pressure difference between arms and cardiovascular disease in the Framingham Heart Study.

Science.gov (United States)

Weinberg, Ido; Gona, Philimon; O'Donnell, Christopher J; Jaff, Michael R; Murabito, Joanne M

2014-03-01

An increased interarm systolic blood pressure difference is an easily determined physical examination finding. The relationship between interarm systolic blood pressure difference and risk of future cardiovascular disease is uncertain. We described the prevalence and risk factor correlates of interarm systolic blood pressure difference in the Framingham Heart Study (FHS) original and offspring cohorts and examined the association between interarm systolic blood pressure difference and incident cardiovascular disease and all-cause mortality. An increased interarm systolic blood pressure difference was defined as ≥ 10 mm Hg using the average of initial and repeat blood pressure measurements obtained in both arms. Participants were followed through 2010 for incident cardiovascular disease events. Multivariable Cox proportional hazards regression analyses were performed to investigate the effect of interarm systolic blood pressure difference on incident cardiovascular disease. We examined 3390 (56.3% female) participants aged 40 years and older, free of cardiovascular disease at baseline, mean age of 61.1 years, who attended a FHS examination between 1991 and 1994 (original cohort) and from 1995 to 1998 (offspring cohort). The mean absolute interarm systolic blood pressure difference was 4.6 mm Hg (range 0-78). Increased interarm systolic blood pressure difference was present in 317 (9.4%) participants. The median follow-up time was 13.3 years, during which time 598 participants (17.6%) experienced a first cardiovascular event, including 83 (26.2%) participants with interarm systolic blood pressure difference ≥ 10 mm Hg. Compared with those with normal interarm systolic blood pressure difference, participants with an elevated interarm systolic blood pressure difference were older (63.0 years vs 60.9 years), had a greater prevalence of diabetes mellitus (13.3% vs 7.5%,), higher systolic blood pressure (136.3 mm Hg vs 129.3 mm Hg), and a higher total cholesterol

Validity of predicting left ventricular end systolic pressure changes following an acute bout of exercise.

Science.gov (United States)

Kappus, Rebecca M; Ranadive, Sushant M; Yan, Huimin; Lane, Abbi D; Cook, Marc D; Hall, Grenita; Harvey, I Shevon; Wilund, Kenneth R; Woods, Jeffrey A; Fernhall, Bo

2013-01-01

Left ventricular end systolic pressure (LV ESP) is important in assessing left ventricular performance and is usually derived from prediction equations. It is unknown whether these equations are accurate at rest or following exercise in a young, healthy population. Measured LV ESP vs. LV ESP values from the prediction equations were compared at rest, 15 min and 30 min following peak aerobic exercise in 60 participants. LV ESP was obtained by applanation tonometry at rest, 15 min post and 30 min post peak cycle exercise. Measured LV ESP was significantly lower (p<0.05) at all time points in comparison to the two calculated values. Measured LV ESP decreased significantly from rest at both the post15 and post30 time points (p<0.05) and changed differently in comparison to the calculated values (significant interaction; p<0.05). The two LV ESP equations were also significantly different from each other (p<0.05) and changed differently over time (significant interaction; p<0.05). The two commonly used prediction equations did not accurately predict either resting or post exercise LV ESP in a young, healthy population. Thus, LV ESP needs to be individually determined in young, healthy participants. Non-invasive measurement through applanation tonometry appears to allow for a more accurate determination of LV ESP. Copyright © 2012 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Impact of age on pulmonary artery systolic pressures at rest and with exercise

Directory of Open Access Journals (Sweden)

Garvan C Kane

2016-06-01

Full Text Available Aim: It is not well known if advancing age influences normal rest or exercise pulmonary artery pressures. The purpose of the study was to evaluate the association of increasing age with measurements of pulmonary artery systolic pressure at rest and with exercise. Subjects and methods: A total of 467 adults without cardiopulmonary disease and normal exercise capacity (age range: 18–85 years underwent symptom-limited treadmill exercise testing with Doppler measurement of rest and exercise pulmonary artery systolic pressure. Results: There was a progressive increase in rest and exercise pulmonary artery pressures with increasing age. Pulmonary artery systolic pressures at rest and with exercise were 25 ± 5 mmHg and 33 ± 9 mmHg, respectively, in those <40 years, and 30 ± 5 mmHg and 41 ± 12 mmHg, respectively, in those ≥70 years. While elevated left-sided cardiac filling pressures were excluded by protocol design, markers of arterial stiffness associated with the age-dependent effects on pulmonary pressures. Conclusion: These data demonstrate that in echocardiographically normal adults, pulmonary artery systolic pressure increases with advancing age. This increase is seen at rest and with exercise. These increases in pulmonary pressure occur in association with decreasing transpulmonary flow and increases in systemic pulse pressure, suggesting that age-associated blood vessel stiffening may contribute to these differences in pulmonary artery systolic pressure.

Right Heart End-Systolic Remodeling Index Strongly Predicts Outcomes in Pulmonary Arterial Hypertension: Comparison With Validated Models.

Science.gov (United States)

Amsallem, Myriam; Sweatt, Andrew J; Aymami, Marie C; Kuznetsova, Tatiana; Selej, Mona; Lu, HongQuan; Mercier, Olaf; Fadel, Elie; Schnittger, Ingela; McConnell, Michael V; Rabinovitch, Marlene; Zamanian, Roham T; Haddad, Francois

2017-06-01

Right ventricular (RV) end-systolic dimensions provide information on both size and function. We investigated whether an internally scaled index of end-systolic dimension is incremental to well-validated prognostic scores in pulmonary arterial hypertension. From 2005 to 2014, 228 patients with pulmonary arterial hypertension were prospectively enrolled. RV end-systolic remodeling index (RVESRI) was defined by lateral length divided by septal height. The incremental values of RV free wall longitudinal strain and RVESRI to risk scores were determined. Mean age was 49±14 years, 78% were female, 33% had connective tissue disease, 52% were in New York Heart Association class ≥III, and mean pulmonary vascular resistance was 11.2±6.4 WU. RVESRI and right atrial area were strongly connected to the other right heart metrics. Three zones of adaptation (adapted, maladapted, and severely maladapted) were identified based on the RVESRI to RV systolic pressure relationship. During a mean follow-up of 3.9±2.4 years, the primary end point of death, transplant, or admission for heart failure was reached in 88 patients. RVESRI was incremental to risk prediction scores in pulmonary arterial hypertension, including the Registry to Evaluate Early and Long-Term PAH Disease Management score, the Pulmonary Hypertension Connection equation, and the Mayo Clinic model. Using multivariable analysis, New York Heart Association class III/IV, RVESRI, and log NT-proBNP (N-Terminal Pro-B-Type Natriuretic Peptide) were retained (χ 2 , 62.2; P right heart metrics, RVESRI demonstrated the best test-retest characteristics. RVESRI is a simple reproducible prognostic marker in patients with pulmonary arterial hypertension. © 2017 American Heart Association, Inc.

Recruitment strategies and challenges in a large intervention trial: Systolic Blood Pressure Intervention Trial.

Science.gov (United States)

Ramsey, Thomas M; Snyder, Joni K; Lovato, Laura C; Roumie, Christianne L; Glasser, Steven P; Cosgrove, Nora M; Olney, Christine M; Tang, Rocky H; Johnson, Karen C; Still, Carolyn H; Gren, Lisa H; Childs, Jeffery C; Crago, Osa L; Summerson, John H; Walsh, Sandy M; Perdue, Letitia H; Bankowski, Denise M; Goff, David C

2016-06-01

The Systolic Blood Pressure Intervention Trial is a multicenter, randomized clinical trial of 9361 participants with hypertension who are ≥50 years old. The trial is designed to evaluate the effect of intensive systolic blood pressure control (systolic blood pressure goal recruitment strategies and lessons learned during recruitment of the Systolic Blood Pressure Intervention Trial cohort and five targeted participant subgroups: pre-existing cardiovascular disease, pre-existing chronic kidney disease, age ≥75 years, women, and minorities. In collaboration with the National Institutes of Health Project Office and Systolic Blood Pressure Intervention Trial Coordinating Center, five Clinical Center Networks oversaw clinical site selection, recruitment, and trial activities. Recruitment began on 8 November 2010 and ended on 15 March 2013 (about 28 months). Various recruitment strategies were used, including mass mailing, brochures, referrals from healthcare providers or friends, posters, newspaper ads, radio ads, and electronic medical record searches. Recruitment was scheduled to last 24 months to enroll a target of 9250 participants; in just over 28 months, the trial enrolled 9361 participants. The trial screened 14,692 volunteers, with 33% of initial screens originating from the use of mass mailing lists. Screening results show that participants also responded to recruitment efforts through referral by Systolic Blood Pressure Intervention Trial staff, healthcare providers, or friends (45%); brochures or posters placed in clinic waiting areas (15%); and television, radio, newspaper, Internet ads, or toll-free numbers (8%). The overall recruitment yield (number randomized/number screened) was 64% (9361 randomized/14,692 screened), 77% for those with cardiovascular disease, 79% for those with chronic kidney disease, 70% for those aged ≥75 years, 55% for women, and 61% for minorities. As recruitment was observed to lag behind expectations, additional

The effects of increasing levels of dietary garlic bulb on growth performance, systolic blood pressure, hematology, and ascites syndrome in broiler chickens.

Science.gov (United States)

Varmaghany, Saifali; Karimi Torshizi, Mohammad Amir; Rahimi, Shaban; Lotfollahian, Houshang; Hassanzadeh, Mohammad

2015-08-01

The effects of dietary garlic bulb were studied separately on hematological parameters, ascites incidence, and growth performance of an ascites susceptible broiler hybrid under both standard temperature conditions ( STC: ) and cold temperature conditions ( CTC: ). A total of 336 one-day-old male broiler chickens were allocated to 4 experimental groups with 4 replicates of 21 birds each under STC. In addition, the same grouping with another 336 birds was used for CTC. Under CTC, the birds were exposed to cold temperatures for induction of ascites. Experimental groups were defined by the inclusion of 0 (control), 5, 10 or 15 g/kg garlic bulbs in the diets under both STC and CTC. Growth performance, systolic blood pressure (as a measure of systemic arterial blood pressure), physiological and biochemical parameters, as well as ascites indices (right ventricle [ RV: ], total ventricle [ TV: ] weights, and RV/TV: ) were evaluated. Systolic blood pressure was determined using an indirect method with a sphygmomanometer, a pediatric cuff, and a Doppler device. The final body weight decreased quadratically (P = 0.003), with increasing garlic bulb levels in the diets under STC. The feed conversion ratio showed no significant differences among all groups under both STC and CTC. No significant differences were observed in total mortality and ascites-related mortality in all groups under STC, although total mortality (L: P = 0.01; Q: P = 0.001) and ascites-related mortality (L: P = 0.007; Q: P = 0.001) were significantly different among the diets under CTC. Under STC, the systolic blood pressure, packed cell volume, hemoglobin, RV, TV, and RV/TV did not vary significantly among the diets. However, red blood cell count and erythrocyte osmotic fragility decreased linearly (P garlic bulb levels in the diets under STC. Under CTC, the systolic blood pressure, packed cell volume, red blood cell count, and erythrocyte osmotic fragility decreased (P garlic levels. It is

Second measurement of morning systolic blood pressure is more closely associated with albuminuria.

Science.gov (United States)

Sakabe, Kazumi; Fukui, Michiaki; Ushigome, Emi; Hamaguchi, Masahide; Tanaka, Toru; Atsuta, Haruhiko; Ohnishi, Masayoshi; Oda, Yohei; Hasegawa, Goji; Nakamura, Naoto

2012-08-01

It is important to control blood pressure as well as to control blood glucose for the prevention of diabetic nephropathy. However, to our knowledge, there are no reports investigating which blood pressure, including morning, evening and clinic, is more closely associated with albuminuria and whether one measurement is sufficient or not in patients with Type 2 diabetes. We measured morning, evening and clinic blood pressure and compared the area under the curve (AUC) of blood pressure for urinary albumin excretion equal to or more than 30 mg/g creatinine using receiver-operating characteristic curve analyses and odds ratio for albuminuria defined as urinary albumin excretion equal to or more than 30 mg/g creatinine in 858 patients with Type 2 diabetes. Odds ratio (95% confidence interval (CI)) of morning, evening and clinic systolic blood pressure for albuminuria was 1.034 (1.024 - 1.044), 1.033 (1.023 - 1.043) and 1.013 (1.055 - 1.021), respectively (p AUC of morning, evening and clinic systolic blood pressure was 0.644 (0.628 - 0.700) (p AUC of the second morning systolic blood pressure was greater than the first (p = 0.033). The second measurement of morning systolic blood pressure is more closely associated with albuminuria than the first measurement of the morning in addition to clinic systolic blood pressure.

Clinical application of a right ventricular pressure-volume loop determined by gated blood-pool imaging and simultaneously measured right ventricular pressure

International Nuclear Information System (INIS)

Yasue, Takao; Watanabe, Sachiro; Sugishita, Nobuyoshi; Tanaka, Tsutomu; Yokoyama, Hideo

1983-01-01

The data obtained by ECG-gated radionuclide angiography were collected simultaneously with right ventricular pressure and thermal cardiac output (CO) obtained by a Swan-Ganz catheter in Scintipac 1200 (Shimazu Co) in order to create a right ventricular pressure-volume (RV P-V) loop. Subjects consisted of 15 patients with old myocardial infarction (MI group), seven with angina pectoris (AP group), six with congestive cardiomyopathy (CCM group) and five with neurocirculatory asthenia (NCA group). Right ventricular end-diastolic volume (RVEDV) was calculated as RVEDV = CO/(EF x HR) (CO = cardiac output; HR = heart rate). Systolic work (W sub(S)), diastolic work (W sub(D)) and net work (W sub(N)) were calculated from a RV P-V loop by Simpson's method. The measurements were performed before and 5 min after sublingual administration of nitroglycerin (NG) (0.3 mg). The results were as follows: 1. RV P-V loops shifted towards the left lower part of the P-V plane after sublingual administration of nitroglycerin, indicating the reduction of pressure and volume of the right ventricle. 2. Right ventricular ejection fraction (RVEF) in the MI, AP and CCM groups showed smaller values than that of the NCA group. 3. Right ventricular end-diastolic volume index (RVEDVI) showed a converse relation with RVEF. 4. Cardiac index in all groups decreased after NG and a statistical significance was seen in the MI, AP and NCA groups (p<0.05). 5. RV W sub(S), RV W sub(D) and RV W sub(N) showed no difference among each groups in the control state, and significantly decreased after NG. We conclude that the present method using RV P-V loop might be useful as a noninvasive bedside monitoring and permits the evaluation of RV function in a clinical setting

Dairy consumption, systolic blood pressure, and risk of hypertension: Mendelian randomization study

Science.gov (United States)

This study examined whether previous observed inverse associations of dairy intake with systolic blood pressure and risk of hypertension were causal. A Mendelian randomization study was employed, using the single nucleotide polymorphism rs4988235 related to lactase persistence as an instrumental var...

Relationship Between 24-Hour Ambulatory Central Systolic Blood Pressure and Left Ventricular Mass: A Prospective Multicenter Study.

Science.gov (United States)

Weber, Thomas; Wassertheurer, Siegfried; Schmidt-Trucksäss, Arno; Rodilla, Enrique; Ablasser, Cornelia; Jankowski, Piotr; Lorenza Muiesan, Maria; Giannattasio, Cristina; Mang, Claudia; Wilkinson, Ian; Kellermair, Jörg; Hametner, Bernhard; Pascual, Jose Maria; Zweiker, Robert; Czarnecka, Danuta; Paini, Anna; Salvetti, Massimo; Maloberti, Alessandro; McEniery, Carmel

2017-12-01

We investigated the relationship between left ventricular mass and brachial office as well as brachial and central ambulatory systolic blood pressure in 7 European centers. Central systolic pressure was measured with a validated oscillometric device, using a transfer function, and mean/diastolic pressure calibration. M-mode images were obtained by echocardiography, and left ventricular mass was determined by one single reader blinded to blood pressure. We studied 289 participants (137 women) free from antihypertensive drugs (mean age: 50.8 years). Mean office blood pressure was 145/88 mm Hg and mean brachial and central ambulatory systolic pressures were 127 and 128 mm Hg, respectively. Mean left ventricular mass was 93.3 kg/m 2 , and 25.6% had left ventricular hypertrophy. The correlation coefficient between left ventricular mass and brachial office, brachial ambulatory, and central ambulatory systolic pressure was 0.29, 0.41, and 0.47, respectively ( P =0.003 for comparison between brachial office and central ambulatory systolic pressure and 0.32 for comparison between brachial and central ambulatory systolic pressure). The results were consistent for men and women, and young and old participants. The areas under the curve for prediction of left ventricular hypertrophy were 0.618, 0.635, and 0.666 for brachial office, brachial, and central ambulatory systolic pressure, respectively ( P =0.03 for comparison between brachial and central ambulatory systolic pressure). In younger participants, central ambulatory systolic pressure was superior to both other measurements. Central ambulatory systolic pressure, measured with an oscillometric cuff, shows a strong trend toward a closer association with left ventricular mass and hypertrophy than brachial office/ambulatory systolic pressure. URL: https://www.clinicaltrials.gov. Unique identifier: NCT01278732. © 2017 American Heart Association, Inc.

Closure of digital arteries in high vascular tone states as demonstrated by measurement of systolic blood pressure in the fingers

DEFF Research Database (Denmark)

Krähenbühl, B; Nielsen, S L; Lassen, N A

1977-01-01

by direct cooling or intra-arterial noradrenaline infusion caused a marked drop in FSP in the exposed fingers, but not in the non-exposed fingers of the same hand. The fact that the non-exposed fingers retained the normal (arm systolic) pressure level is taken to indicate that palmar arch blood pressure......Finger systolic blood pressure (FSP) was measured indirectly in normal subjects and patients with primary Raynaud phenomenon by applying a thin-walled plastic cuff around the finger and a strain gauge more distally to detect volume changes. Inducing a high vascular tone in one or more fingers...... also remained normal. In the high vascular tone state, a large transmural pressure difference must apparently be established before the digital arteries are forced open. The lowered opening pressure constitutes a manifestation of the closure phenomenon of the digital arteries described in patients...

Analysis of the progression of systolic blood pressure using imputation of missing phenotype values

OpenAIRE

Vaitsiakhovich, Tatsiana; Drichel, Dmitriy; Angisch, Marina; Becker, Tim; Herold, Christine; Lacour, André

2014-01-01

We present a genome-wide association study of a quantitative trait, "progression of systolic blood pressure in time," in which 142 unrelated individuals of the Genetic Analysis Workshop 18 real genotype data were analyzed. Information on systolic blood pressure and other phenotypic covariates was missing at certain time points for a considerable part of the sample. We observed that the dropout process causing missingness is not independent of the initial systolic blood pressure; that is, the ...

Differential Systolic and Diastolic Regulation of the Cerebral Pressure-Flow Relationship During Squat-Stand Manoeuvres.

Science.gov (United States)

Smirl, Jonathan D; Wright, Alexander D; Ainslie, Philip N; Tzeng, Yu-Chieh; van Donkelaar, Paul

2018-01-01

Cerebral pressure-flow dynamics are typically reported between mean arterial pressure and mean cerebral blood velocity. However, by reporting only mean responses, potential differential regulatory properties associated with systole and diastole may have been overlooked. Twenty young adults (16 male, age: 26.7 ± 6.6 years, BMI: 24.9 ± 3.0 kg/m 2 ) were recruited for this study. Middle cerebral artery velocity was indexed via transcranial Doppler. Cerebral pressure-flow dynamics were assessed using transfer function analysis at both 0.05 and 0.10 Hz using squat-stand manoeuvres. This method provides robust and reliable measures for coherence (correlation index), phase (timing buffer) and gain (amplitude buffer) metrics. There were main effects for both cardiac cycle and frequency for phase and gain metrics (p flow relationship. The oscillations associated with systole are extensively buffered within the cerebrovasculature, whereas diastolic oscillations are relatively unaltered. This indicates that the brain is adapted to protect itself against large increases in systolic blood pressure, likely as a mechanism to prevent cerebral haemorrhages.

Epicardial left ventricular lead placement for cardiac resynchronization therapy: optimal pace site selection with pressure-volume loops.

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Dekker, A L A J; Phelps, B; Dijkman, B; van der Nagel, T; van der Veen, F H; Geskes, G G; Maessen, J G

2004-06-01

Patients in heart failure with left bundle branch block benefit from cardiac resynchronization therapy. Usually the left ventricular pacing lead is placed by coronary sinus catheterization; however, this procedure is not always successful, and patients may be referred for surgical epicardial lead placement. The objective of this study was to develop a method to guide epicardial lead placement in cardiac resynchronization therapy. Eleven patients in heart failure who were eligible for cardiac resynchronization therapy were referred for surgery because of failed coronary sinus left ventricular lead implantation. Minithoracotomy or thoracoscopy was performed, and a temporary epicardial electrode was used for biventricular pacing at various sites on the left ventricle. Pressure-volume loops with the conductance catheter were used to select the best site for each individual patient. Relative to the baseline situation, biventricular pacing with an optimal left ventricular lead position significantly increased stroke volume (+39%, P =.01), maximal left ventricular pressure derivative (+20%, P =.02), ejection fraction (+30%, P =.007), and stroke work (+66%, P =.006) and reduced end-systolic volume (-6%, P =.04). In contrast, biventricular pacing at a suboptimal site did not significantly change left ventricular function and even worsened it in some cases. To optimize cardiac resynchronization therapy with epicardial leads, mapping to determine the best pace site is a prerequisite. Pressure-volume loops offer real-time guidance for targeting epicardial lead placement during minimal invasive surgery.

Relation Between Pressure and Volume Unloading During Ramp Testing in Patients Supported with a Continuous-Flow Left Ventricular Assist Device

DEFF Research Database (Denmark)

Jung, Mette H; Hassager, Christian; Balling, Louise

2015-01-01

Pulmonary capillary wedge pressure (PCWP) is the key to describing left ventricular (LV) unloading, however, the relation between pressure and the echocardiography-derived surrogate of LV volume (left ventricular end-diastolic diameter (LVEDD)) as a function of pump speed (RPM) in continuous......-flow left ventricular assist device (CF-LVAD) patients is unknown. In this study the pressure-volume relationship as a function of RPM during ramp testing was investigated by simultaneously measuring PCWP by Swan-Ganz catheter and LVEDD by echocardiography. The ramp protocol started at usual pump setting...

Total flying hours and risk of high systolic blood pressure in the civilian pilot in Indonesia

Directory of Open Access Journals (Sweden)

Ferdi Afian

2016-07-01

Full Text Available Abstrak Latar belakang: Tekanan darah sistolik tinggi di antara pilot sipil antara lain akan menyebabkan gangguan kardiovaskular sehingga akan mengganggu kelancaran penerbangan. Tujuan penelitian ini ialah untuk mengetahui faktor-faktor dominan terhadap tekanan darah sistolik tinggi pada pilot sipil. Metode: Penelitian potong lintang dengan metode sampling purposif pada pilot yang melakukan pemeriksaan kesehatan berkala di Balai Kesehatan Penerbangan pada tanggal 18-29 Mei 2015. Data yang dikumpulkan adalah karakteristik demografi dan pekerjaan, klinis, kebiasaan olahraga, kebiasaan makan, indeks massa tubuh dan riwayat penyakit. Tekanan darah sistolik tinggi ialah tekanan darah sistolik140 mmHg atau lebih. Hasil: Dari 690 pilot yang melakukan pemeriksaan kesehatan berkala, 428 pilot laki-laki bersedia berpartisipasi mengikuti penelitian ini. Usia dan riwayat penyakit hipertensi merupakan faktor risiko dominan yang berhubungan dengan tekanan darah sistolik tinggi. Jika dibandingkan dengan pilot usia 19-39 tahun, yang berusia 40-65 tahun mempunyai 15,1 kali lipat lebih besar risiko terkena tekanan darah sistolik tinggi [rasio odds suaian (ORa= 15,12; p= 0,001]. Pilot dengan riwayat penyakit hipertensi dibandingkan dengan yang tidak ada riwayat memiliki risiko tekanan darah sistolik tinggi 93,2 kali lipat lebih besar (ORa= 93,21; p= 0,001 Kesimpulan: Usia 40-65 tahun dan memiliki riwayat hipertensi meningkatkan risiko tekanan darah sistolik tinggi di antara pilot sipil di Indonesia. Kata kunci: tekanan darah sistolik, total jam terbang, pilot sipil, Indonesia.  Abstract Background: Systolic high blood pressure among civilian pilots among others will cause cardiovascular disease and this condition will disrupt the flight.The purpose of this study was to identified the dominant factors related to high systolic blood pressure in the civilian pilots. Methods: A cross-sectional study with a purposive sampling method on a pilot who performed periodic

The effect of chronic digitalization on pump function in systolic heart failure.

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Hassapoyannes, C A; Easterling, B M; Chavda, K; Chavda, K K; Movahed, M R; Welch, G W

2001-10-01

Short- and intermediate-term use of cardiac glycosides promotes inotropy and improves the ejection fraction in systolic heart failure. To determine whether chronic digitalization alters left ventricular function and performance. Eighty patients with mild-to-moderate systolic heart failure (baseline ejection fraction < or =45%) participated from our institution in a multi-center, chronic, randomized, double-blind study of digitalis vs. placebo. Of the 40 survivors, 38 (20 allocated to the digitalis arm and 18 to the placebo arm) were evaluated at the end of follow-up (mean, 48.4 months). Left ventricular systolic function was assessed by both nuclear ventriculography and echocardiography. The ejection fraction was measured scintigraphically, while the ventricular volumes were computed echocardiographically. The groups did not differ, at baseline or end-of-study, with respect to the ejection fraction and the loading conditions (arterial pressure, ventricular volumes and heart rate) by either intention-to-treat or actual-treatment-received analysis. Over the course of the trial, the digitalis arm exhibited no significant increase in the use of diuretics (18%, P=0.33), in distinction from the placebo group (78%, P=0.004), and a longer stay on study drug among those patients who withdrew from double-blind treatment (28.6 vs. 11.4 months, P=0.01). Following chronic use of digitalis for mild-to-moderate heart failure, cross-sectional comparison with a control group from the same inception cohort showed no appreciable difference in systolic function or performance. Thus, the suggested clinical benefit cannot be explained by an inotropic effect.

Left ventricular volume analysis as a basic tool to describe cardiac function.

Science.gov (United States)

Kerkhof, Peter L M; Kuznetsova, Tatiana; Ali, Rania; Handly, Neal

2018-03-01

The heart is often regarded as a compression pump. Therefore, determination of pressure and volume is essential for cardiac function analysis. Traditionally, ventricular performance was described in terms of the Starling curve, i.e., output related to input. This view is based on two variables (namely, stroke volume and end-diastolic volume), often studied in the isolated (i.e., denervated) heart, and has dominated the interpretation of cardiac mechanics over the last century. The ratio of the prevailing coordinates within that paradigm is termed ejection fraction (EF), which is the popular metric routinely used in the clinic. Here we present an insightful alternative approach while describing volume regulation by relating end-systolic volume (ESV) to end-diastolic volume. This route obviates the undesired use of metrics derived from differences or ratios, as employed in previous models. We illustrate basic principles concerning ventricular volume regulation by data obtained from intact animal experiments and collected in healthy humans. Special attention is given to sex-specific differences. The method can be applied to the dynamics of a single heart and to an ensemble of individuals. Group analysis allows for stratification regarding sex, age, medication, and additional clinically relevant covariates. A straightforward procedure derives the relationship between EF and ESV and describes myocardial oxygen consumption in terms of ESV. This representation enhances insight and reduces the impact of the metric EF, in favor of the end-systolic elastance concept advanced 4 decades ago.

Closure of digital arteries in high vascular tone states as demonstrated by measurement of systolic blood pressure in the fingers

DEFF Research Database (Denmark)

Krähenbühl, B; Nielsen, S L; Lassen, N A

1977-01-01

Finger systolic blood pressure (FSP) was measured indirectly in normal subjects and patients with primary Raynaud phenomenon by applying a thin-walled plastic cuff around the finger and a strain gauge more distally to detect volume changes. Inducing a high vascular tone in one or more fingers by ...

Systolic hypertension: an increasing clinical challenge in Asia

Science.gov (United States)

Park, Jeong Bae; Kario, Kazuomi; Wang, Ji-Guang

2015-01-01

Systolic hypertension, the predominant form of hypertension in patients aged over 50–60 years, is a growing health issue as the Asian population ages. Elevated systolic blood pressure is mainly caused by arterial stiffening, resulting from age-related vascular changes. Elevated systolic pressure increases the risk of cardiovascular disease, mortality and renal function decline, and this risk may increase at lower systolic pressure levels in Asian than Western subjects. Hence, effective systolic pressure lowering is particularly important in Asians yet blood pressure control remains inadequate despite the availability of numerous antihypertensive medications. Reasons for poor blood pressure control include low awareness of hypertension among health-care professionals and patients, under-treatment, and tolerability problems with antihypertensive drugs. Current antihypertensive treatments also lack effects on the underlying vascular pathology of systolic hypertension, so novel drugs that address the pathophysiology of arterial stiffening are needed for optimal management of systolic hypertension and its cardiovascular complications. PMID:25503845

Nonlinear isochrones in murine left ventricular pressure-volume loops: how well does the time-varying elastance concept hold?

Science.gov (United States)

Claessens, T E; Georgakopoulos, D; Afanasyeva, M; Vermeersch, S J; Millar, H D; Stergiopulos, N; Westerhof, N; Verdonck, P R; Segers, P

2006-04-01

The linear time-varying elastance theory is frequently used to describe the change in ventricular stiffness during the cardiac cycle. The concept assumes that all isochrones (i.e., curves that connect pressure-volume data occurring at the same time) are linear and have a common volume intercept. Of specific interest is the steepest isochrone, the end-systolic pressure-volume relationship (ESPVR), of which the slope serves as an index for cardiac contractile function. Pressure-volume measurements, achieved with a combined pressure-conductance catheter in the left ventricle of 13 open-chest anesthetized mice, showed a marked curvilinearity of the isochrones. We therefore analyzed the shape of the isochrones by using six regression algorithms (two linear, two quadratic, and two logarithmic, each with a fixed or time-varying intercept) and discussed the consequences for the elastance concept. Our main observations were 1) the volume intercept varies considerably with time; 2) isochrones are equally well described by using quadratic or logarithmic regression; 3) linear regression with a fixed intercept shows poor correlation (R(2) volume intercept of the ESPVR. In conclusion, the linear time-varying elastance fails to provide a sufficiently robust model to account for changes in pressure and volume during the cardiac cycle in the mouse ventricle. A new framework accounting for the nonlinear shape of the isochrones needs to be developed.

Systolic blood pressure is superior to other haemodynamic predictors of outcome in community acquired pneumonia.

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Chalmers, J D; Singanayagam, A; Hill, A T

2008-08-01

Admission blood pressure (BP) assessment is a central component of severity assessment for community acquired pneumonia. The aim of this study was to establish which readily available haemodynamic measure on admission is most useful for predicting severity in patients admitted with community acquired pneumonia. A prospective observational study of patients admitted with community acquired pneumonia was conducted in Edinburgh, UK. The measurements compared were systolic and diastolic BP, mean arterial pressure and pulse pressure. The outcomes of interest were 30 day mortality and the requirement for mechanical ventilation and/or inotropic support. Admission systolic BP pressure pressure AUC values for each predictor of 30 day mortality were as follows: systolic BP pressure pressure AUC values for each predictor of need for mechanical ventilation and/or inotropic support were as follows: systolic BP pressure pressure blood pressure AUC 0.76 vs 0.74) and to the standard CURB65 score (0.76 vs 0.76) for the prediction of 30 day mortality. The simplified CRB65 score was equivalent for prediction of mechanical ventilation and/or inotropic support to standard CRB65 (0.77 vs 0.77) and to CURB65 (0.77 vs 0.78). Systolic BP is superior to other haemodynamic predictors of 30 day mortality and need for mechanical ventilation and/or inotropic support in community acquired pneumonia. The CURB65 score can be simplified to a modified CRB65 score by omission of the diastolic BP criterion without compromising its accuracy.

Inter-arm systolic blood pressure differences, relations with future vascular events and mortality in patients with and without manifest vascular disease.

Science.gov (United States)

Kranenburg, Guido; Spiering, Wilko; de Jong, Pim A; Kappelle, L Jaap; de Borst, Gert Jan; Cramer, Maarten J; Visseren, Frank L J; Aboyans, Victor; Westerink, Jan

2017-10-01

Inter-arm systolic blood pressure difference (SBPD) is an easily obtained patient characteristic which relates to vascular disease. We aimed to identify determinants of large inter-arm SBPD and to investigate the relation between inter-arm SBPD and vascular events in patients with and without manifest vascular disease. In a cohort of 7344 patients with manifest vascular disease or vascular risk factors alone enrolled in the Second Manifestations of ARTerial disease (SMART) study, single bilateral non-simultaneous blood pressure measurements were performed. Logistic and Cox regression was used to identify determinants of large inter-arm SBPD (≥15mmHg) and to investigate the relation between inter-arm SBPD and vascular events (composite of non-fatal myocardial infarction, stroke, and vascular mortality) and all-cause mortality. In all patients the median inter-arm SBPD was 7mmHg (IQR 3-11) and 1182 (16%) patients had inter-arm SBPD ≥15mmHg. Higher age, higher systolic blood pressure, diabetes mellitus, peripheral artery disease, carotid artery stenosis, higher carotid intima-media thickness, and lower ankle-brachial indices were related to large inter-arm SBPD (≥15mmHg). Each 5mmHg increase in inter-arm SBPD was related to a 12% higher risk of vascular events in patients without manifest vascular disease (HR 1.12; 95% CI 1.00-1.27), whereas no relation was apparent in patients with manifest vascular disease (HR 0.98; 95% CI 0.93-1.04, interaction p-value 0.036). Inter-arm SBPD was not related to all-cause mortality (HR 1.05; 95% CI 0.93-1.19). Inter-arm SBPD relates to a higher risk of vascular events in patients without manifest vascular disease, whereas this relation is not apparent in patients with manifest vascular disease. Copyright © 2017 Elsevier B.V. All rights reserved.

Interaction between intra-abdominal pressure and positive-end expiratory pressure

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Jamili Anbar Torquato

2009-02-01

Full Text Available OBJECTIVE: The aim of this study was to quantify the interaction between increased intra-abdominal pressure and Positive-End Expiratory Pressure. METHODS: In 30 mechanically ventilated ICU patients with a fixed tidal volume, respiratory system plateau and abdominal pressure were measured at a Positive-End Expiratory Pressure level of zero and 10 cm H2O. The measurements were repeated after placing a 5 kg weight on the patients' belly. RESULTS: After the addition of 5 kg to the patients' belly at zero Positive-End Expiratory Pressure, both intra-abdominal pressure (p<0.001 and plateau pressures (p=0.005 increased significantly. Increasing the Positive-End Expiratory Pressure levels from zero to 10 cm H2O without weight on the belly did not result in any increase in intra-abdominal pressure (p=0.165. However, plateau pressures increased significantly (p< 0.001. Increasing Positive-End Expiratory Pressure from zero to 10 cm H2O and adding 5 kg to the belly increased intra-abdominal pressure from 8.7 to 16.8 (p<0.001 and plateau pressure from 18.26 to 27.2 (p<0.001. Maintaining Positive-End Expiratory Pressure at 10 cm H2O and placing 5 kg on the belly increased intra-abdominal pressure from 12.3 +/- 1.7 to 16.8 +/- 1.7 (p<0.001 but did not increase plateau pressure (26.6+/-1.2 to 27.2 +/-1.1 -p=0.83. CONCLUSIONS: The addition of a 5kg weight onto the abdomen significantly increased both IAP and the airway plateau pressure, confirming that intra-abdominal hypertension elevates the plateau pressure. However, plateau pressure alone cannot be considered a good indicator for the detection of elevated intra-abdominal pressure in patients under mechanical ventilation using PEEP. In these patients, the intra-abdominal pressure must also be measured.

Low tidal volume ventilation ameliorates left ventricular dysfunction in mechanically ventilated rats following LPS-induced lung injury.

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Cherpanath, Thomas G V; Smeding, Lonneke; Hirsch, Alexander; Lagrand, Wim K; Schultz, Marcus J; Groeneveld, A B Johan

2015-10-07

High tidal volume ventilation has shown to cause ventilator-induced lung injury (VILI), possibly contributing to concomitant extrapulmonary organ dysfunction. The present study examined whether left ventricular (LV) function is dependent on tidal volume size and whether this effect is augmented during lipopolysaccharide(LPS)-induced lung injury. Twenty male Wistar rats were sedated, paralyzed and then randomized in four groups receiving mechanical ventilation with tidal volumes of 6 ml/kg or 19 ml/kg with or without intrapulmonary administration of LPS. A conductance catheter was placed in the left ventricle to generate pressure-volume loops, which were also obtained within a few seconds of vena cava occlusion to obtain relatively load-independent LV systolic and diastolic function parameters. The end-systolic elastance / effective arterial elastance (Ees/Ea) ratio was used as the primary parameter of LV systolic function with the end-diastolic elastance (Eed) as primary LV diastolic function. Ees/Ea decreased over time in rats receiving LPS (p = 0.045) and high tidal volume ventilation (p = 0.007), with a lower Ees/Ea in the rats with high tidal volume ventilation plus LPS compared to the other groups (p tidal volume ventilation without LPS (p = 0.223). A significant interaction (p tidal ventilation and LPS for Ees/Ea and Eed, and all rats receiving high tidal volume ventilation plus LPS died before the end of the experiment. Low tidal volume ventilation ameliorated LV systolic and diastolic dysfunction while preventing death following LPS-induced lung injury in mechanically ventilated rats. Our data advocates the use of low tidal volumes, not only to avoid VILI, but to avert ventilator-induced myocardial dysfunction as well.

24-hour central aortic systolic pressure and 24-hour central pulse pressure are related to diabetic complications in type 1 diabetes - a cross-sectional study

DEFF Research Database (Denmark)

Theilade, Simone; Lajer, Maria Stenkil; Hansen, Tine Willum

2013-01-01

BACKGROUND: Non-invasive measurements of 24 hour ambulatory central aortic systolic pressure (24 h-CASP) and central pulse pressure (24 h-CPP) are now feasible. We evaluate the relationship between 24 h central blood pressure and diabetes-related complications in patients with type 1 diabetes.......68) and 3.72 (1.85-7.47) and autonomic dysfunction: 3.25 (1.65-6.41), 1.64 (1.12-2.39) and 2.89 (1.54-5.42). CONCLUSIONS: 24 h-CASP and 24 h-CPP was higher in patients vs. controls and increased with diabetic complications independently of covariates. Furthermore, 24 h-CASP was stronger associated....... METHODS: The study was cross-sectional, including 715 subjects: 86 controls (C), 69 patients with short diabetes duration (diabetes (≥ 10 years) and normoalbuminuria (LN), 163...

Hemodynamic responses to external counterbalancing of auto-positive end-expiratory pressure in mechanically ventilated patients with chronic obstructive pulmonary disease.

Science.gov (United States)

Baigorri, F; de Monte, A; Blanch, L; Fernández, R; Vallés, J; Mestre, J; Saura, P; Artigas, A

1994-11-01

To study the effect of positive end-expiratory pressure (PEEP) on right ventricular hemodynamics and ejection fraction in patients with chronic obstructive pulmonary disease and positive alveolar pressure throughout expiration by dynamic hyperinflation (auto-PEEP). Open, prospective, controlled trial. General intensive care unit of a community hospital. Ten patients sedated and paralyzed with an acute exacerbation of chronic obstructive pulmonary disease undergoing mechanical ventilation. Insertion of a pulmonary artery catheter modified with a rapid response thermistor and a radial arterial catheter. PEEP was then increased from 0 (PEEP 0) to auto-PEEP level (PEEP = auto-PEEP) and 5 cm H2O above that (PEEP = auto-PEEP +5). At each level of PEEP, airway pressures, flow and volume, hemodynamic variables (including right ventricular ejection fraction by thermodilution technique), and blood gas analyses were recorded. The mean auto-PEEP was 6.6 +/- 2.8 cm H2O and the total PEEP reached was 12.2 +/- 2.4 cm H2O. The degree of lung inflation induced by PEEP averaged 145 +/- 87 mL with PEEP = auto-PEEP and 495 +/- 133 mL with PEEP = auto-PEEP + 5. The PEEP = auto-PEEP caused a right ventricular end-diastolic pressure increase, but there was no other significant hemodynamic change. With PEEP = auto-PEEP + 5, there was a significant increase in intravascular pressures; this amount of PEEP reduced cardiac output (from 4.40 +/- 1.38 L/min at PEEP 0 to 4.13 +/- 1.48 L/min; p 10% in only five cases and this group of patients had significantly lower right ventricular volumes than the group with less cardiac output variation (right ventricular end-diastolic volume: 64 +/- 9 vs. 96 +/- 26 mL/m2; right ventricular end-systolic volume: 38 +/- 6 vs. 65 +/- 21 mL/m2; p < .05) without significant difference in the other variables that were measured. Neither right ventricular ejection fraction nor right ventricle volumes changed as PEEP increased, but there were marked interpatient

Assessment of vasodilator therapy in patients with severe congestive heart failure: limitations of measurements of left ventricular ejection fraction and volumes

International Nuclear Information System (INIS)

Firth, B.G.; Dehmer, G.J.; Markham, R.V. Jr.; Willerson, J.T.; Hillis, L.D.

1982-01-01

Although noninvasive techniques are often used to assess the effect of vasodilator therapy in patients with congestive heart failure, it is unknown whether changes in noninvasively determined left ventricular ejection fraction, volume, or dimension reliably reflect alterations in intracardiac pressure and flow. Accordingly, we compared the acute effect of sodium nitroprusside on left ventricular volume and ejection fraction (determined scintigraphically) with its effect on intracardiac pressure and forward cardiac index (determined by thermodilution) in 12 patients with severe, chronic congestive heart failure and a markedly dilated left ventricle. Nitroprusside (infused at 1.3 +/- 1.1 [mean +/- standard deviation] microgram/kg/min) caused a decrease in mean systemic arterial, mean pulmonary arterial, and mean pulmonary capillary wedge pressure as well as a concomitant increase in forward cardiac index. Simultaneously, left ventricular end-diastolic and end-systolic volume indexes decreased, but the scintigraphically determined cardiac index did not change significantly. Left ventricular ejection fraction averaged 0.19 +/- 0.05 before nitroprusside administration and increased by less than 0.05 units in response to nitroprusside in 11 of 12 patients. The only significant correlation between scintigraphically and invasively determined variables was that between the percent change in end-diastolic volume index and the percent change in pulmonary capillary wedge pressure (r . 0.68, p . 0.01). Although nitroprusside produced changes in scintigraphically determined left ventricular ejection fraction, end-systolic volume index, and cardiac index, these alterations bore no predictable relation to changes in intracardiac pressure, forward cardiac index, or vascular resistance. Furthermore, nitroprusside produced a considerably greater percent change in the invasively measured variables than in the scintigraphically determined ones

Systolic hypertension in adult nigerians with hypertension

International Nuclear Information System (INIS)

Opadijo, O.G.; Salami, T.A.T.; Sanya, E.O.; Omotoso, A.B.O.

2007-01-01

To determine the prevalence of both systolic and diastolic hypertensions in relation to age and their impacts on target organ among adult Nigerians with hypertension. Newly diagnosed adult hypertensives, with blood pressure 140/90mm Hg, taken twice with mercury column sphygmomanometer at 3 weeks interval, were studied. The total number of hypertensive patients treated over this period was also taken into consideration. The newly diagnosed hypertensives were classified using JNC VI classification. The frequency of occurrence of target organ damage such as Left Ventricular Hypertrophy (LVH), heart failure, renal impairment etc. was charted according to systolic and or diastolic pressures. The occurrence of systolic or diastolic blood pressure was also related with the age of the patients. Blood metabolic parameters were compared in both systolic and diastolic blood pressures for their possible contributory role. Two thousand seven hundred and ninety-two adult hypertensive patients were managed over the study period. Of them, 218 (7.8%) were newly diagnosed and studied. There were 94 males and 124 females. Seventy-seven (35.3%) were aged 60 years and above with equal frequency in the gender. One hundred and seventy-eight (81.7%) cases had combined systolic and diastolic pressures. Twenty-nine (13.3%) patients had systolic hypertension. Twenty-five (86.2%) of these 29 were aged 50 years and above and 20 (69.0%) were aged 60 years and above. Eleven (5.0%) patients had isolated diastolic hypertension and they were all in the age bracket 40-49 years. Systolic blood pressure was found to be rising with advancing age while diastolic blood pressure peaked at mid 40's and declined. Target organ damage occurred more frequently with systolic hypertension and advancing age than with diastolic hypertension. Systolic hypertension occurred more frequently in this series of adult Nigerians with hypertension. It was higher with advancing age and associated with more target organ

Increased postdialysis systolic blood pressure is associated with extracellular overhydration in hemodialysis outpatients.

Science.gov (United States)

Nongnuch, Arkom; Campbell, Neil; Stern, Edward; El-Kateb, Sally; Fuentes, Laura; Davenport, Andrew

2015-02-01

Recently, intradialytic hypertension was reported to be associated with increased mortality for hemodialysis patients. To determine whether volume status plays a role in dialysis-associated hypertension, we prospectively audited 531 patients that had volume assessments measured by multiple-frequency bioelectrical impedance during their midweek dialysis session. Mean pre- and postdialysis weights were 73.2 vs 71.7 kg, and systolic blood pressures (SBPs) 140.5 vs. 130.3 mm Hg, respectively. Patients were divided into groups based on a fall in SBP of 20 mm Hg or more (32%), an increased SBP of 10 mm Hg or more (18%), and a stable group (50%). There were no differences in patient demographics, dialysis prescriptions, predialysis weight, total body (TBW), and extracellular (ECW) and intracellular water (ICW). However, the change in weight was significantly less in the increased blood pressure group (1.01 kg vs. stable 1.65, and 1.7 hypotensive). The ratio of ECW to TBW was significantly higher in the increased blood pressure group, particularly post dialysis (39.1 vs. stable 38.7% and fall in blood pressure group 38.7%). ECW overhydration was significantly greater in the increased blood pressure group post dialysis (0.7 (0.17 to 1.1) vs. stable 0.39 (-0.2 to 0.95) and fall in blood pressure group 0.38 (-0.19 to 0.86) liter). We found that patients who had increased blood pressure post dialysis had greater hydration status, particularly ECW. Thus, patients who increase their blood pressure post dialysis should have review of target weight, consideration of lowering the post-dialysis weight, and may benefit from increasing dialysis session time or frequency.

Can a central blood volume deficit be detected by systolic pressure variation during spontaneous breathing?

DEFF Research Database (Denmark)

Dahl, Michael; Hayes, Chris; Steen Rasmussen, Bodil

2016-01-01

BACKGROUND: Whether during spontaneous breathing arterial pressure variations (APV) can detect a volume deficit is not established. We hypothesized that amplification of intra-thoracic pressure oscillations by breathing through resistors would enhance APV to allow identification of a reduced card...

The measurement of digital systolic blood pressure by strain gauge technique

DEFF Research Database (Denmark)

Nielsen, P E; Bell, G; Lassen, N A

1972-01-01

The systolic blood pressure on the finger, toe, and ankle has been measured by a strain gauge technique in 10 normal subjects aged 17-31 years and 14 normal subjects aged 43-57 years. The standard deviation in repeated measurements lies between 2 and 6 mm Hg. The finger pressure in the younger...... group was significantly higher than the corresponding arm pressure (+ 9.3 mm Hg, S.D. 6.8), but equalled this in the older group (- 0.5 mm Hg, S.D. 6.6). In the two groups the ankle pressures were + 19.3 mm Hg (S.D. 7.5) and + 23.6 mm Hg (S.D. 9.5) higher than the systolic arm pressures. The toe...... pressures were lower than the arm pressures, in the two groups - 4.8 mm Hg (S.D. 6.6) and - 9.8 mm Hg (S.D. 10.7) respectively. The ankle-toe gradient was in the younger group 24.3 mm Hg (S.D. 7.3) and in the older group 33.3 mm Hg (S.D. 12.1). Using mean minus 2.5 X S.D. as the lower limit of normality...

Peripheral arterial volume distensibility: significant differences with age and blood pressure measured using an applied external pressure

International Nuclear Information System (INIS)

Zheng, Dingchang; Murray, Alan

2011-01-01

A new arterial distensibility measurement technique was assessed in 100 healthy normotensive subjects. Arterial transmural pressures on the whole right arm were reduced with a 50 cm long cuff inflated to 10, 20, 30 and 40 mmHg. The electrocardiogram, and finger and ear photoplethysmograms were recorded simultaneously. Arm pulse propagation time, pulse wave velocity (PWV) and arterial volume distensibility were determined. With a 40 mmHg reduction in transmural pressure, arm pulse propagation time increased from 61 to 83 ms, PWV decreased from 12 to 8 m s −1 and arterial distensibility increased from 0.102% to 0.232% per mmHg (all P < 0.0001). At all cuff pressures, arterial distensibility was significantly related to resting mean arterial pressure (MAP), diastolic blood pressure (DBP) and age, and for systolic blood pressure at 30 and 40 mmHg (all P < 0.05). At 40 mmHg cuff pressure, arterial distensibility fell by 54% for a MAP increase from 75 to 105 mmHg, 57% for a DBP increase from 60 to 90 mmHg and 47% for an age increase from 20 to 70 years. These changes were more than double than those without cuff pressure. Our technique showed that systemic volume distensibility of the peripheral arm artery reduced with age, with a greater effect at higher external and lower transmural pressures

Echocardiographic Parameters and Survival in Chagas Heart Disease with Severe Systolic Dysfunction

International Nuclear Information System (INIS)

Rassi, Daniela do Carmo; Vieira, Marcelo Luiz Campos; Arruda, Ana Lúcia Martins; Hotta, Viviane Tiemi; Furtado, Rogério Gomes; Rassi, Danilo Teixeira; Rassi, Salvador

2014-01-01

Echocardiography provides important information on the cardiac evaluation of patients with heart failure. The identification of echocardiographic parameters in severe Chagas heart disease would help implement treatment and assess prognosis. To correlate echocardiographic parameters with the endpoint cardiovascular mortality in patients with ejection fraction < 35%. Study with retrospective analysis of pre-specified echocardiographic parameters prospectively collected from 60 patients included in the Multicenter Randomized Trial of Cell Therapy in Patients with Heart Diseases (Estudo Multicêntrico Randomizado de Terapia Celular em Cardiopatias) - Chagas heart disease arm. The following parameters were collected: left ventricular systolic and diastolic diameters and volumes; ejection fraction; left atrial diameter; left atrial volume; indexed left atrial volume; systolic pulmonary artery pressure; integral of the aortic flow velocity; myocardial performance index; rate of increase of left ventricular pressure; isovolumic relaxation time; E, A, Em, Am and Sm wave velocities; E wave deceleration time; E/A and E/Em ratios; and mitral regurgitation. In the mean 24.18-month follow-up, 27 patients died. The mean ejection fraction was 26.6 ± 5.34%. In the multivariate analysis, the parameters ejection fraction (HR = 1.114; p = 0.3704), indexed left atrial volume (HR = 1.033; p < 0.0001) and E/Em ratio (HR = 0.95; p = 0.1261) were excluded. The indexed left atrial volume was an independent predictor in relation to the endpoint, and values > 70.71 mL/m 2 were associated with a significant increase in mortality (log rank p < 0.0001). The indexed left atrial volume was the only independent predictor of mortality in this population of Chagasic patients with severe systolic dysfunction

Echocardiographic Parameters and Survival in Chagas Heart Disease with Severe Systolic Dysfunction

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Rassi, Daniela do Carmo, E-mail: dani.rassi@hotmail.com [Faculdade de Medicina e Hospital das Clínicas da Universidade Federal de Goiás (UFG), Goiânia, GO (Brazil); Vieira, Marcelo Luiz Campos [Instituto do Coração da Faculdade de Medicina da Universidade de São Paulo (USP), São Paulo, SP (Brazil); Arruda, Ana Lúcia Martins [Instituto de Radiologia da Faculdade de Medicina da Universidade de São Paulo (USP), São Paulo, SP (Brazil); Hotta, Viviane Tiemi [Instituto do Coração da Faculdade de Medicina da Universidade de São Paulo (USP), São Paulo, SP (Brazil); Furtado, Rogério Gomes; Rassi, Danilo Teixeira; Rassi, Salvador [Faculdade de Medicina e Hospital das Clínicas da Universidade Federal de Goiás (UFG), Goiânia, GO (Brazil)

2014-03-15

Echocardiography provides important information on the cardiac evaluation of patients with heart failure. The identification of echocardiographic parameters in severe Chagas heart disease would help implement treatment and assess prognosis. To correlate echocardiographic parameters with the endpoint cardiovascular mortality in patients with ejection fraction < 35%. Study with retrospective analysis of pre-specified echocardiographic parameters prospectively collected from 60 patients included in the Multicenter Randomized Trial of Cell Therapy in Patients with Heart Diseases (Estudo Multicêntrico Randomizado de Terapia Celular em Cardiopatias) - Chagas heart disease arm. The following parameters were collected: left ventricular systolic and diastolic diameters and volumes; ejection fraction; left atrial diameter; left atrial volume; indexed left atrial volume; systolic pulmonary artery pressure; integral of the aortic flow velocity; myocardial performance index; rate of increase of left ventricular pressure; isovolumic relaxation time; E, A, Em, Am and Sm wave velocities; E wave deceleration time; E/A and E/Em ratios; and mitral regurgitation. In the mean 24.18-month follow-up, 27 patients died. The mean ejection fraction was 26.6 ± 5.34%. In the multivariate analysis, the parameters ejection fraction (HR = 1.114; p = 0.3704), indexed left atrial volume (HR = 1.033; p < 0.0001) and E/Em ratio (HR = 0.95; p = 0.1261) were excluded. The indexed left atrial volume was an independent predictor in relation to the endpoint, and values > 70.71 mL/m{sup 2} were associated with a significant increase in mortality (log rank p < 0.0001). The indexed left atrial volume was the only independent predictor of mortality in this population of Chagasic patients with severe systolic dysfunction.

Ratio of systolic blood pressure to left ventricular end-diastolic pressure at the time of primary percutaneous coronary intervention predicts in-hospital mortality in patients with ST-elevation myocardial infarction.

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Sola, Michael; Venkatesh, Kiran; Caughey, Melissa; Rayson, Robert; Dai, Xuming; Stouffer, George A; Yeung, Michael

2017-09-01

To determine the ability of simple hemodynamic parameters obtained at the time of cardiac catheterization to predict in-hospital mortality following ST-elevation myocardial infarction (STEMI). Hemodynamic parameters measured at the time of primary percutaneous coronary intervention (PPCI) could potentially identify high-risk patients who would benefit from aggressive hemodynamic support in the Cardiac Catheterization laboratory. This is a retrospective single-center study of 219 consecutive patients with STEMI. Left ventricular end-diastolic pressure (LVEDP), systolic blood pressure (SBP), and aortic diastolic blood pressure were obtained after successful revascularization. The prognostic ability of LVEDP, pulse pressure, and SBP/LVEDP ratio were compared to major mortality risk scores. Patients had a mean age of 60 ±14 years, were predominantly white (73%), male (64%), with anterior wall infarcts in 39%. Comorbidities included diabetes mellitus (27%), heart failure (9%), and chronic kidney disease (7%). In-hospital mortality was 9%. Patients with SBP/LVEDP ≤ 4 had increased risk of in-hospital death (32% vs. 5.3%, P  4. The area under curve (AUC) for SBP/LVEDP ratio for in-hospital mortality (0.69) was more predictive than LVEDP (0.61, P = 0.04) or pulse pressure (0.55, P = 0.02) but similar to Shock Index (ratio of heart rate to SBP) and Modified Shock Index (ratio of HR to mean arterial pressure). An SBP/LVEDP ratio ≤ 4 identified a group of STEMI patients at high risk of in-hospital death. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Acute Effects of Positive Airway Pressure on Functional Mitral Regurgitation in Patients with Systolic Heart Failure

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Takao Kato

2017-11-01

Full Text Available Background: Acute effects of positive airway pressure (PAP [including continuous PAP (CPAP and adaptive servo-ventilation, an advanced form of bi-level PAP] on functional mitral regurgitation (fMR in patients with heart failure (HF with left ventricular (LV systolic dysfunction remain unclear. Thus, whether PAP therapy reduces fMR in such patients with HF was investigated.Methods and Results: Twenty patients with HF and LV systolic dysfunction defined as LV ejection fraction (LVEF <50% (14 men; mean LVEF, 35.0 ± 11.5% with fMR underwent echocardiography during 10-min CPAP (4 and 8 cm H2O and adaptive servo-ventilation. For fMR assessment, MR jet area fraction, defined as the ratio of MR jet on color Doppler to the left atrial area, was measured. The forward stroke volume (SV index (fSVI was calculated from the time-velocity integral, cross-sectional area of the aortic annulus, and body surface area. fMR significantly reduced on CPAP at 8 cm H2O (0.30 ± 0.12 and adaptive servo-ventilation (0.29 ± 0.12, compared with the baseline phase (0.37 ± 0.12 and CPAP at 4 cm H2O (0.34 ± 0.12 (P < 0.001. The fSVI did not change in any of the PAP sessions (P = 0.888. However, significant differences in fSVI responses to PAP were found between sexes (P for interaction, 0.006, with a significant reduction in fSVI in women (P = 0.041 and between patients with baseline fSVI ≥ and < the median value (27.8 ml/m2, P for interaction, 0.018, with a significant fSVI reduction in patients with high baseline fSVI (P = 0.028. In addition, significant differences were found in fSVI responses to PAP between patients with LV end-systolic volume (LVESV index ≥ and < the median value (62.0 ml/m2, P for interaction, 0.034, with a significant fSVI increase in patients with a high LVESV index (P = 0.023.Conclusion: In patients with HF, LV systolic dysfunction, and fMR, PAP can alleviate fMR without any overall changes in forward SV. However, MR alleviation due to PAP

A CROSS SECTIONAL STUDY TO FIND THE DIFFERENCE IN SYSTOLIC BLOOD PRESSURE BETWEEN ARMS AS A RISK MARKER FOR DIABETIC NEPHROPATHY IN PATIENTS WITH TYPE 2 DIABETES MELLITUS

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Uday Subhash Bande

2016-08-01

Full Text Available BACKGROUND Diabetic nephropathy is the commonest cause of end-stage renal disease in the developed world. Recent studies have demonstrated that a difference in systolic blood pressure between arms is associated with cardiovascular disease and microalbuminuria. It is considered a predictor for cardiovascular disease and a surrogate marker for early kidney damage among patients with both type 2 diabetes and hypertension. AIMS AND OBJECTIVES The aim was to investigate an association between arm difference in systolic blood pressure and microalbuminuria which can serve as a marker for diabetic nephropathy. MATERIALS AND METHOD This study was conducted on 200 patients with diabetes mellitus and an inter-arm difference in systolic blood pressure was present in 35.7% of the study population. Presence of systolic blood pressure difference of more than 10 mmHg between arms correlated with microalbuminuria and duration of diabetes mellitus with a p value of <0.001. We also found a correlation between arm difference in blood pressure and duration of diabetes mellitus, presence of hypertension and body mass index. CONCLUSION The inter-arm difference in blood pressure could serve as a risk marker for renal damage in diabetes mellitus.

Interankle systolic blood pressure difference and renal outcomes in patients with chronic kidney disease.

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Chen, Szu-Chia; Tsai, Yi-Chun; Huang, Jiun-Chi; Lee, Su-Chu; Chang, Jer-Ming; Hwang, Shang-Jyh; Chen, Hung-Chun

2016-05-01

Interankle blood pressure (BP) difference has been associated with peripheral artery disease and adverse cardiovascular outcomes. However, the relationship between interankle BP difference and renal outcomes in chronic kidney disease (CKD) has never been evaluated. The purpose of this study was to determine whether interankle BP difference is associated with the rate of renal function decline and progression to renal end points in patients with stage 3-5 CKD. We enrolled 144 patients with CKD from one regional hospital. The BP in four limbs was simultaneously measured using an ABI-form device. The decline in renal function was evaluated using an estimated glomerular filtration rate (eGFR) slope. Rapid renal progression was defined as an eGFR slope < -3 mL/min per 1.73 m(2) per year. The renal end points were defined as ≥ 25% decline in eGFR or commencement of dialysis during the follow-up period. During a mean follow-up period of 3.1 years, 90 patients (62.5%) reached renal end points. Multivariate analysis showed that an increased interankle systolic BP difference (per 5 mmHg) was associated with a worse eGFR slope (regression β, -0.292; 95% confidence interval [CI], -0.482 to -0.102; P = 0.003), rapid renal progression (odds ratio, 1.189; 95% CI, 1.015-1.394; P = 0.032), and an increased risk of progression to renal end points (hazard ratio, 1.126; 95% CI, 1.052-1.204, P = 0.001). Interankle systolic BP difference was associated with rapid renal progression and progression to renal end points in patients with stage 3-5 CKD in our study. © 2015 Asian Pacific Society of Nephrology.

Systolic left ventricular function according to left ventricular concentricity and dilatation in hypertensive patients

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Bang, Casper; Gerdts, Eva; Aurigemma, Gerard P

2013-01-01

Left ventricular hypertrophy [LVH, high left ventricular mass (LVM)] is traditionally classified as concentric or eccentric based on left ventricular relative wall thickness. We evaluated left ventricular systolic function in a new four-group LVH classification based on left ventricular dilatation...... [high left ventricular end-diastolic volume (EDV) index and concentricity (LVM/EDV)] in hypertensive patients....

Contribution of the Arterial System and the Heart to Blood Pressure during Normal Aging - A Simulation Study.

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Maksuti, Elira; Westerhof, Nico; Westerhof, Berend E; Broomé, Michael; Stergiopulos, Nikos

2016-01-01

During aging, systolic blood pressure continuously increases over time, whereas diastolic pressure first increases and then slightly decreases after middle age. These pressure changes are usually explained by changes of the arterial system alone (increase in arterial stiffness and vascular resistance). However, we hypothesise that the heart contributes to the age-related blood pressure progression as well. In the present study we quantified the blood pressure changes in normal aging by using a Windkessel model for the arterial system and the time-varying elastance model for the heart, and compared the simulation results with data from the Framingham Heart Study. Parameters representing arterial changes (resistance and stiffness) during aging were based on literature values, whereas parameters representing cardiac changes were computed through physiological rules (compensated hypertrophy and preservation of end-diastolic volume). When taking into account arterial changes only, the systolic and diastolic pressure did not agree well with the population data. Between 20 and 80 years, systolic pressure increased from 100 to 122 mmHg, and diastolic pressure decreased from 76 to 55 mmHg. When taking cardiac adaptations into account as well, systolic and diastolic pressure increased from 100 to 151 mmHg and decreased from 76 to 69 mmHg, respectively. Our results show that not only the arterial system, but also the heart, contributes to the changes in blood pressure during aging. The changes in arterial properties initiate a systolic pressure increase, which in turn initiates a cardiac remodelling process that further augments systolic pressure and mitigates the decrease in diastolic pressure.

Intraoperative and postoperative evaluation of low tidal volume combined with low-level positive end-expiratory pressure ventilation in laparoscopic surgery in elderly patients

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Ye-Qiu Li

2016-01-01

Full Text Available Objective: To evaluate intraoperative and postoperative condition of low tidal volume combined with low-level positive end-expiratory pressure ventilation in laparoscopic surgery in elderly patients. Methods: A total of 176 cases of elderly patients (more than 60 years old receiving laparoscopic surgery in our hospital from July 2013 to July 2015 were selected as research subjects and randomly divided into observation group and control group, each group included 88 cases, control group received conventional ventilation strategy, observation group received low tidal volume combined with low-level positive end-expiratory pressure ventilation strategy, and then levels of hemodynamic indexes, respiratory mechanical indexes, serology indexes and cerebral vessel related indexes, etc of two groups were compared. Results: Intraoperative and postoperative heart rate and mean arterial pressure levels of observation group were lower than those of control group, arterial partial pressure of oxygen and oxygenation index levels were higher than those of control group and differences had statistical significance (P<0.05; intraoperative APIP and Pplat values of observation group were lower than those of control group, Cs value was higher than that of control group and differences had statistical significance (P<0.05; intraoperative and postoperative serum IL-8 and TNF-α levels of observation group were lower than those of control group, IL-10 level was higher than that of control group and differences had statistical significance (P<0.05; intraoperative and postoperative PjvO2, SjvO2 and CjvO2 levels of observation group were higher than those of control group, Da-jvO2 level was lower than that of control group and differences had statistical significance (P<0.05. Conclusions: When elderly patients receive laparoscopic surgery, the use of low tidal volume combined with low-level positive end-expiratory pressure ventilation strategy can stabilize hemodynamic

Different systolic blood pressure targets for people with history of stroke or transient ischaemic attack: PAST-BP (Prevention After Stroke—Blood Pressure) randomised controlled trial

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McManus, Richard J; Roalfe, Andrea; Fletcher, Kate; Taylor, Clare J; Martin, Una; Virdee, Satnam; Greenfield, Sheila; Hobbs, F D Richard

2016-01-01

Objective To assess whether using intensive blood pressure targets leads to lower blood pressure in a community population of people with prevalent cerebrovascular disease. Design Open label randomised controlled trial. Setting 99 general practices in England, with participants recruited in 2009-11. Participants People with a history of stroke or transient ischaemic attack whose systolic blood pressure was 125 mm Hg or above. Interventions Intensive systolic blood pressure target (different target, patients in both arms were actively managed in the same way with regular reviews by the primary care team. Main outcome measure Change in systolic blood pressure between baseline and 12 months. Results 529 patients (mean age 72) were enrolled, 266 to the intensive target arm and 263 to the standard target arm, of whom 379 were included in the primary analysis (182 (68%) intensive arm; 197 (75%) standard arm). 84 patients withdrew from the study during the follow-up period (52 intensive arm; 32 standard arm). Mean systolic blood pressure dropped by 16.1 mm Hg to 127.4 mm Hg in the intensive target arm and by 12.8 mm Hg to 129.4 mm Hg in the standard arm (difference between groups 2.9 (95% confidence interval 0.2 to 5.7) mm Hg; P=0.03). Conclusions Aiming for target below 130 mm Hg rather than 140 mm Hg for systolic blood pressure in people with cerebrovascular disease in primary care led to a small additional reduction in blood pressure. Active management of systolic blood pressure in this population using a blood pressure. Trial registration Current Controlled Trials ISRCTN29062286. PMID:26919870

Echocardiographic parameters and survival in Chagas heart disease with severe systolic dysfunction.

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Rassi, Daniela do Carmo; Vieira, Marcelo Luiz Campos; Arruda, Ana Lúcia Martins; Hotta, Viviane Tiemi; Furtado, Rogério Gomes; Rassi, Danilo Teixeira; Rassi, Salvador

2014-03-01

Echocardiography provides important information on the cardiac evaluation of patients with heart failure. The identification of echocardiographic parameters in severe Chagas heart disease would help implement treatment and assess prognosis. To correlate echocardiographic parameters with the endpoint cardiovascular mortality in patients with ejection fraction Celular em Cardiopatias) - Chagas heart disease arm. The following parameters were collected: left ventricular systolic and diastolic diameters and volumes; ejection fraction; left atrial diameter; left atrial volume; indexed left atrial volume; systolic pulmonary artery pressure; integral of the aortic flow velocity; myocardial performance index; rate of increase of left ventricular pressure; isovolumic relaxation time; E, A, Em, Am and Sm wave velocities; E wave deceleration time; E/A and E/Em ratios; and mitral regurgitation. In the mean 24.18-month follow-up, 27 patients died. The mean ejection fraction was 26.6 ± 5.34%. In the multivariate analysis, the parameters ejection fraction (HR = 1.114; p = 0.3704), indexed left atrial volume (HR = 1.033; p 70.71 mL/m2 were associated with a significant increase in mortality (log rank p < 0.0001). The indexed left atrial volume was the only independent predictor of mortality in this population of Chagasic patients with severe systolic dysfunction.

Flow-related Right Ventricular - Pulmonary Arterial Pressure Gradients during Exercise.

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Wright, Stephen P; Opotowsky, Alexander R; Buchan, Tayler A; Esfandiari, Sam; Granton, John T; Goodman, Jack M; Mak, Susanna

2018-06-06

The assumption of equivalence between right ventricular and pulmonary arterial systolic pressure is fundamental to several assessments of right ventricular or pulmonary vascular hemodynamic function. Our aims were to 1) determine whether systolic pressure gradients develop across the right ventricular outflow tract in healthy adults during exercise, 2) examine the potential correlates of such gradients, and 3) consider the effect of such gradients on calculated indices of right ventricular function. Healthy untrained and endurance-trained adult volunteers were studied using right-heart catheterization at rest and during submaximal cycle ergometry. Right ventricular and pulmonary artery pressures were simultaneously transduced, and cardiac output was determined by thermodilution. Systolic pressures, peak and mean gradients, and indices of chamber, vascular, and valve function were analyzed offline. Summary data are reported as mean ± standard deviation or median [interquartile range]. No significant right ventricular outflow tract gradients were observed at rest (mean gradient = 4 [3-5] mmHg), and calculated effective orifice area was 3.6±1.0 cm2. Right ventricular systolic pressure increases during exercise were greater than that of pulmonary artery systolic pressure. Accordingly, mean gradients developed during light exercise (8 [7-9] mmHg) and increased during moderate exercise (12 [9-14] mmHg, p < 0.001). The magnitude of the mean gradient was linearly related to cardiac output (r2 = 0.70, p < 0.001). In healthy adults without pulmonic stenosis, systolic pressure gradients develop during exercise, and the magnitude is related to blood flow rate.

Isolated Systolic Hypertension: A Health Concern?

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Isolated systolic hypertension: A health concern? Is having a high top number (systolic) blood pressure, but a normal bottom number (diastolic) ... mm Hg, you have a common type of high blood pressure called isolated systolic hypertension. Isolated systolic hypertension can ...

Urinary albumin excretion is associated with nocturnal systolic blood pressure in resistant hypertensives.

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Oliveras, Anna; Armario, Pedro; Martell-Clarós, Nieves; Ruilope, Luis M; de la Sierra, Alejandro

2011-03-01

Microalbuminuria is a known marker of subclinical organ damage. Its prevalence is higher in patients with resistant hypertension than in subjects with blood pressure at goal. On the other hand, some patients with apparently well-controlled hypertension still have microalbuminuria. The current study aimed to determine the relationship between microalbuminuria and both office and 24-hour ambulatory blood pressure. A cohort of 356 patients (mean age 64 ± 11 years; 40.2% females) with resistant hypertension (blood pressure ≥ 140 and/or 90 mm Hg despite treatment with ≥ 3 drugs, diuretic included) were selected from Spanish hypertension units. Patients with estimated glomerular filtration rate <30 mL/min/1.73 m(2) were excluded. All patients underwent clinical and demographic evaluation, complete laboratory analyses, and good technical-quality 24-hour ambulatory blood pressure monitoring. Urinary albumin/creatinine ratio was averaged from 3 first-morning void urine samples. Microalbuminuria (urinary albumin/creatinine ratio ≥ 2.5 mg/mmol in males or ≥ 3.5 mg/mmol in females) was detected in 46.6%, and impaired renal function (estimated glomerular filtration rate <60 mL/min/1.73 m(2)) was detected in 26.8%. Bivariate analyses showed significant associations of microalbuminuria with older age, reduced estimated glomerular filtration rate, increased nighttime systolic blood pressure, and elevated daytime, nighttime, and 24-hour diastolic blood pressure. In a logistic regression analysis, after age and sex adjustment, elevated nighttime systolic blood pressure (multivariate odds ratio, 1.014 [95% CI, 1.001 to 1.026]; P=0.029) and reduced estimated glomerular filtration rate (multivariate odds ratio, 2.79 [95% CI, 1.57 to 4.96]; P=0.0005) were independently associated with the presence of microalbuminuria. We conclude that microalbuminuria is better associated with increased nighttime systolic blood pressure than with any other office and 24-hour ambulatory blood

High baseline left ventricular and systolic volume may identify patients at risk of chemotherapy-induced cardiotoxicity

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Atiar Rahman; Alex Gedevanishvili; Seham Ali; Elma G Briscoe; Vani Vijaykumar

2004-01-01

Introduction and Methods: Use of chemotherapeutic drugs in the treatment of cancer may lead to serious cardiotoxicity and to post-treatment heart failure. Various strategies have been developed to minimize the risk of cardiotoxicity including avoiding the total dosage given to each patient above a certain 'threshold' value; and monitoring the patient's cardiac function by means of the 'Multiple Gated Acquisition' (MUGA) scan using Technetium 99m . However, even with all these precautions some patients still develop cardiotoxicity and it is not well known which factors predict deterioration of cardiac functions in patients with optimized chemotherapeutic dosages. In this retrospective study we sought to evaluate the predictive value of seven variables (age, sex, baseline LV ejection fraction, LV end diastolic [LDEDV] and end systolic volumes [LVESV], peak diastolic filling rate, preexisting malignancies requiring chemotherapy) in 172 patients (n=Breast Carcinoma 86, lymphoma 62, Leukemias and others 24) undergoing chemotherapy from 1995 until 2000. There was no cut off for left ventricular ejection fraction prior to chemotherapy. However, patients were excluded from analysis if they had significant cardiac arrhythmias or received doses higher than considered safe for cardiotoxicity at the beginning of the study. Significant cardiotoxicity was defined as a drop in post chemotherapy LVEF by >15%. Results: Logistic regression models were used to predict the probability of developing cardiotoxicity as a function of the seven prognostic covariates. The mean age of all patients was 51+13 years. Significant Cardiac toxicity was noted in 10 percent of patients. The overall risk estimate for subsequent heart failure after chemotherapy, however, climbed to 18 percent in patients with a presenting LVESD >50 mL. Using multivariate logistic regression model, older age was noted to be a weak risk factors for cardiac toxicity (confidence interval 0.8-1.2; p 50 mL) appeared to

The correlation between psychological intervention and heart rate,systolic pressure in patients of cervical cancer treated with interventional chemoembolization

International Nuclear Information System (INIS)

Qiao Cuiyun; Lan Guiyun; Liu Shuang; Chen Bao'e; Liu Yali; Wang Zhujun

2010-01-01

Objective: To discuss the effect of psychological intervention on the heart rate, systolic pressure of the patients with cervical cancer who are treated with interventional chemoembolization. Methods: Eighty patients with cervical cancer were randomly and equally divided into two groups. Transcatheter arterial chemoembolization (TACE) was performed in all cases. Patients in study group (n=10) received systemic psychological intervention 30 minutes before TACE. The heart rate and systolic pressure of the patients were measured when TACE started. The results were compared with that obtained at the time of admission. Patients in control group (n=10) did not receive systemic psychological intervention before TACE and their heart rate and systolic pressure were measured in the same way as in study group. Results: At the time TACE started the heart rate and systolic pressure of the patients in study group were significantly lower than that in control group (P < 0.05). Conclusion: Preoperative psychological intervention is very helpful for reducing psychological stress and mental tension,in stabilizing heart rate and systolic pressure of the patients with cervical cancer who are treated with TACE. (authors)

Determination of Relations between Systolic Blood Pressure and Heart Attack in Patients with Type 2 Diabetes with Association Rules

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Seyyed Payam Shariatpanahi

2018-03-01

Full Text Available Abstract Background: Today, the high prevalence of diabetes and its complications are one of the most important public health issues worldwide. For this reason, finding relations between diabetes risk factors is very effective in preventing and reducing complications. For discovering these relations, the data mining methods can be used. By extracting association rules, which is one of the data mining techniques, we can discover the relations between a large numbers of variables in a disease. Materials and Methods: The population of this study was 1046 patients with type 2 diabetes, whose data had recorded between 2011 and 2014 at the Special Clinic for Diabetes in Tehran's Imam Khomeini Hospital. After pre-processing step with SPSS19 software, 573 people entered the analysis phase. The FP-Growth algorithm was applied to the data set to discover the relations between heart attack and other risk factors using Rapid miner5 software. Relations, after extraction, were given to the doctor to confirm clinical validation. Results: The obtained results of studying these 573 people (Including 292 (51% women and 281 (49% men, with age range 27 to 82 years showed that the lack of blood pressure, creatinine and diastolic blood pressure at its normal level, despite higher systolic blood pressure level than normal, doesn't increase the probability of heart attack. Conclusion: Using association rules is a good way of identifying relations between the risk factors of a disease. Also, it can provide new hypotheses to do epidemiological studies for researchers.

Ratio of Systolic Blood Pressure to Right Atrial Pressure, a Novel Marker to Predict Morbidity and Mortality in Acute Systolic Heart Failure.

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Omar, Hesham R; Charnigo, Richard; Guglin, Maya

2017-04-01

Congestion is the main contributor to heart failure (HF) morbidity and mortality. We assessed the combined role of congestion and decreased forward flow in predicting morbidity and mortality in acute systolic HF. The Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness trial data set was used to determine if the ratio of simultaneously measured systolic blood pressure (SBP)/right atrial pressure (RAP) on admission predicted HF rehospitalization and 6-month mortality. One hundred ninety-five patients (mean age 56.5 years, 75% men) who received pulmonary artery catheterization were studied. The RAP, SBP, and SBP/RAP had an area under the curve (AUC) of 0.593 (p = 0.0205), 0.585 (p = 0.0359), and 0.621 (p = 0.0026), respectively, in predicting HF rehospitalization. The SBP/RAP was a superior marker of HF rehospitalization compared with RAP alone (difference in AUC 0.0289, p = 0.0385). The optimal criterion of SBP/RAP AUC 0.622, p = 0.0108, and a cut-off value of SBP/RAP <8 had a sensitivity of 61.9% and specificity 64.1% in predicting mortality. Multivariate analysis showed that an SBP/RAP <11 independently predicted rehospitalization for HF (estimated odds ratio 3.318, 95% confidence interval 1.692 to 6.506, p = 0.0005) and an SBP/RAP <8 independently predicted mortality (estimated hazard ratio 2.025, 95% confidence interval 1.069 to 3.833, p = 0.030). In conclusion, SBP/RAP ratio is a marker that identifies a spectrum of complications after hospitalization of patients with decompensated systolic HF, starting with increased incidence of HF rehospitalization at SBP/RAP <11 to increased mortality with SBP/RAP <8. Copyright © 2017 Elsevier Inc. All rights reserved.

Three-Dimensional Echocardiography-Derived Non-Invasive Right Ventricular Pressure-Volume Analysis.

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Huang, Kuan-Chih; Lin, Lian-Yu; Hwang, Juey-Jen; Lin, Lung-Chun

2017-09-01

In patients with pulmonary hypertension, repeated evaluations of right ventricular (RV) function are still required for clinical decision making, but the invasive nature of current pressure-volume analysis makes conducting regular follow-ups in a clinical setting infeasible. We enrolled 12 patients with pulmonary arterial hypertension (PAH) and 10 with pulmonary venous hypertension (PVH) May 2016-October 2016. All patients underwent a clinically indicated right heart catheterization (RHC), from which the yielded right ventricular pressure recordings were conjugated with RV volume by 3-D echocardiography to generate a pressure-volume loop. A continuous-wave Doppler envelope of tricuspid regurgitation was transformed into a pressure gradient recording by the simplified Bernoulli equation, and then a systolic pressure gradient-volume (PG-V) diagram was generated from similar methods. The area enclosed by the pressure-volume loop was calculated to represent semi-invasive right ventricular stroke work (RVSW RHC ). The area between the PG-V diagram and x-axis was calculated to estimate non-invasive RVSW (RVSW echo ). Patients with PAH have higher RV pressure, lower pulmonary arterial wedge pressure and larger RV volume that was contributed by the dilation of RV mid-cavity minor dimension. We found no significant difference of traditional parameters between these two groups, but RVSW values were significantly higher in PAH patients. The RVSW values of these two methods were significantly correlated by the equation RVSW echo  = 0.8447 RVSW RHC  + 129.38 (R 2  = 0.9151, p rights reserved.

Cholecalciferol treatment to reduce blood pressure in older patients with isolated systolic hypertension: the VitDISH randomized controlled trial.

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Witham, Miles D; Price, Rosemary J G; Struthers, Allan D; Donnan, Peter T; Messow, Claudia-Martina; Ford, Ian; McMurdo, Marion E T

2013-10-14

Observational data link low 25-hydroxyvitamin D levels to both prevalent blood pressure and incident hypertension. No clinical trial has yet examined the effect of vitamin D supplementation in isolated systolic hypertension, the most common pattern of hypertension in older people. To test whether high-dose, intermittent cholecalciferol supplementation lowers blood pressure in older patients with isolated systolic hypertension. Parallel group, double-blind, placebo-controlled randomized trial. Primary care clinics and hospital clinics. Patients 70 years and older with isolated systolic hypertension (supine systolic blood pressure >140 mm Hg and supine diastolic blood pressure blood pressure, 24-hour blood pressure, arterial stiffness, endothelial function, cholesterol level, insulin resistance, and b-type natriuretic peptide level during 12 months. A total of 159 participants were randomized (mean age, 77 years). Mean baseline office systolic blood pressure was 163/78 mm Hg. Mean baseline 25-hydroxyvitamin D level was 18 ng/mL. 25-Hydroxyvitamin D levels increased in the treatment group compared with the placebo group (+8 ng/mL at 1 year, P blood pressure (−1 [−6 to 4]/−2 [−4 to 1] mm Hg at 3 months and 1 [−2 to 4]/0 [−2 to 2] mm Hg overall treatment effect). No significant treatment effect was evident for any of the secondary outcomes (24-hour blood pressure, arterial stiffness, endothelial function, cholesterol level, glucose level, and walking distance). There was no excess of adverse events in the treatment group, and the total number of falls was nonsignificantly lower in the group receiving vitamin D (36 vs 46, P = .24). Vitamin D supplementation did not improve blood pressure or markers of vascular health in older patients with isolated systolic hypertension. isrctn.org Identifier: ISRCTN92186858.

Measurement of pulmonary arterial elastance in patients with systolic heart failure using Doppler echocardiography

Science.gov (United States)

Taghavi, Sepideh; Esmaeilzadeh, Maryam; Amin, Ahmad; Naderi, Nasim; Abkenar, Hooman Bakhshandeh; Maleki, Majid; Mitra, Chitsazan

2016-01-01

Objective: A reliable and easy-to-perform method for measuring right ventricular (RV) afterload is desirable when scheduling patients with systolic heart failure to undergo heart transplantation. The present study aimed to investigate the accuracy of echocardiographically-derived pulmonary arterial elastance as a measurement of pulmonary vascular resistance by comparing it with invasive measures. Methods: Thirty-one patients with moderate to severe systolic heart failure, including 22 (71%) male patients, with a mean age of 41.16±15.9 years were enrolled in the study. Right heart catheterization and comprehensive echocardiography during the first hour after completion of cardiac catheterization were performed in all the patients. The pulmonary artery elastance was estimated using the ratio of end-systolic pressure (Pes) over the stroke volume (SV) by both cardiac catheterization [Ea (PV)-C] and echocardiography [Ea (PV)-E]. Results: The mean Ea (PV)-C and Ea (PV)-E were estimated to be 0.73±0.49 mm Hg/mL and 0.67±0.44 mm Hg/mL, respectively. There was a significant relation between Ea (PV)-E and Ea (PV)-C (r=0.897, pechocardiography and catheterization methods for estimating Ea (PV), investigated by the Bland-Altman method, showed a mean bias of -0.06, with 95% limits of agreement from -0.36 mm Hg/mL to 0.48 mm Hg/mL. Conclusion: Doppler echocardiography is an easy, non-invasive, and inexpensive method for measuring pulmonary arterial elastance, which provides accurate and reliable estimation of RV afterload in patients with systolic heart failure. PMID:26467379

Differential effects of lower body negative pressure and upright tilt on splanchnic blood volume

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Taneja, Indu; Moran, Christopher; Medow, Marvin S.; Glover, June L.; Montgomery, Leslie D.; Stewart, Julian M.

2015-01-01

Upright posture and lower body negative pressure (LBNP) both induce reductions in central blood volume. However, regional circulatory responses to postural changes and LBNP may differ. Therefore, we studied regional blood flow and blood volume changes in 10 healthy subjects undergoing graded lower-body negative pressure (−10 to −50 mmHg) and 8 subjects undergoing incremental head-up tilt (HUT; 20°, 40°, and 70°) on separate days. We continuously measured blood pressure (BP), heart rate, and regional blood volumes and blood flows in the thoracic, splanchnic, pelvic, and leg segments by impedance plethysmography and calculated regional arterial resistances. Neither LBNP nor HUT altered systolic BP, whereas pulse pressure decreased significantly. Blood flow decreased in all segments, whereas peripheral resistances uniformly and significantly increased with both HUT and LBNP. Thoracic volume decreased while pelvic and leg volumes increased with HUT and LBNP. However, splanchnic volume changes were directionally opposite with stepwise decreases in splanchnic volume with LBNP and stepwise increases in splanchnic volume during HUT. Splanchnic emptying in LBNP models regional vascular changes during hemorrhage. Splanchnic filling may limit the ability of the splanchnic bed to respond to thoracic hypovolemia during upright posture. PMID:17085534

Incidence and predictors of end-stage renal disease in outpatients with systolic heart failure

DEFF Research Database (Denmark)

Bosselmann, Helle; Gislason, Gunnar; Gustafsson, Finn

2013-01-01

Background- Renal dysfunction is an important prognostic factor in heart failure (HF), but whether this dysfunction progresses to end-stage renal disease (ESRD) is unknown. Therefore, we examined incidence and predictors of ESRD in outpatients with HF. Methods and Results- Patients with systolic ...

Life course path analysis of birth weight, childhood growth, and adult systolic blood pressure

DEFF Research Database (Denmark)

Gamborg, Michael; Andersen, Per Kragh; Baker, Jennifer L

2009-01-01

body size, and thereby the total effect, of size and changes in size on later outcomes. Using data on childhood body size and adult systolic blood pressure from a sample of 1,284 Danish men born between 1936 and 1970, the authors compared results from path analysis with results from 3 standard...... regression methods. Path analysis produced easily interpretable results, and compared with standard regression methods it produced a noteworthy gain in statistical power. The effect of change in relative body size on adult blood pressure was more pronounced after age 11 years than in earlier childhood....... These results suggest that increases in body size prior to age 11 years are less harmful to adult blood pressure than increases occurring after this age....

Older Women with Controlled Isolated Systolic Hypertension: Exercise and Blood Pressure.

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Ubolsakka-Jones, Chulee; Sangthong, Benjarat; Aueyingsak, Sahachat; Jones, David A

2016-06-01

Exercise is generally regarded as beneficial for health, but the consequent increases in blood pressure might pose a risk for hypertensive subjects. The purpose of this study was to determine blood pressure responses to dynamic exercise and sustained handgrip in patients with isolated systolic hypertension (ISH) who were stable on medication. Nineteen female ISH patients (66 ± 5 yr) and 19 age-matched normotensive (NT) female controls undertook a 5-min cycle exercise (60% heart rate reserve [HRR]) and a 2-min handgrip exercise (30% maximum voluntary contraction). Blood pressure responses were measured using an oscillometric cuff, together with heart rate and resting brachial pulse transit times. Systolic blood pressure (SBP) levels after cycle exercise were 194 ± 18 and 153 ± 19 mm Hg for ISH and NT, respectively, with the increase above resting being greater for ISH (P exercise, SBP rose to 168 ± 19 and 140 ± 8 mm Hg for ISH and NT, respectively. The increases above baseline were greater for ISH both during the exercise and postexercise circulatory occlusion (P = 0.017). The increase in DBP levels during exercise and postexercise occlusion were similar in ISH and NT, suggesting little difference in metaboreflex sensitivity. Pulse transit time was shorter for ISH compared with NT (166 ± 6 ms and 242 ± 24 ms, respectively, P exercises, which may constitute a risk for cardiovascular incidents.

Relationship of end-expiratory pressure, lung volume, and /sup 99m/Tc-DTPA clearance

International Nuclear Information System (INIS)

Cooper, J.A.; van der Zee, H.; Line, B.R.; Malik, A.B.

1987-01-01

We investigated the dose-response effect of positive end-expiratory pressure (PEEP) and increased lung volume on the pulmonary clearance rate of aerosolized technetium-99m-labeled diethylenetriaminepentaacetic acid (99mTc-DTPA). Clearance of lung radioactivity was expressed as percent decrease per minute. Base-line clearance was measured while anesthetized sheep (n = 20) were ventilated with 0 cmH 2 O end-expiratory pressure. Clearance was remeasured during ventilation at 2.5, 5, 10, 15, or 20 cmH 2 O PEEP. Further studies showed stepwise increases in functional residual capacity (FRC) (P less than 0.05) measured at 0, 2.5, 5, 10, 15, and 20 cmH 2 O PEEP. At 2.5 cmH 2 O PEEP, the clearance rate was not different from that at base line (P less than 0.05), although FRC was increased from base line. Clearance rate increased progressively with increasing PEEP at 5, 10, and 15 cmH 2 O (P less than 0.05). Between 15 and 20 cmH 2 O PEEP, clearance rate was again unchanged, despite an increase in FRC. The pulmonary clearance of aerosolized /sup 99m/Tc-DTPA shows a sigmoidal response to increasing FRC and PEEP, having both threshold and maximal effects. This relationship is most consistent with the hypothesis that alveolar epithelial permeability is increased by lung inflation

Radionuclide angiographic evaluation of left ventricular performance at rest and during exercise in patients with aortic regurgitation

International Nuclear Information System (INIS)

Iskandrian, A.S.; Heo, J.

1986-01-01

Radionuclide angiographic evaluation of LV performance at rest and during exercise in patients with AR have shown that an abnormal EF response to exercise may be observed in asymptomatic patients with normal resting LV function. The EF response to exercise has been correlated with a number of clinical and exercise measurements; important among these are the slope of the systolic pressure-to-end-systolic volume, end-systolic volume, cardiac index, pulmonary capillary wedge pressure, and wall stress. The changes in the regurgitant fraction, EF, and LV volume have shown considerable individual variability; they have also allowed a better understanding of the circulatory responses during exercise. Radionuclide angiography provides a reliable and reproducible method of measuring the rest LVEF that is important in the timing and the outcome of valve replacement. The value of the EF response to exercise in patient management is not yet clear; it is possible that other radionuclide-derived measurements at rest or during exercise, such as the systolic pressure-to-end-systolic volume relationship, and the end-systolic volume may provide complementary information to that provided by the EF

[A comparative study between inflation and deflation pressure-volume curve in determining the optimal positive end-expiratory pressure].

Science.gov (United States)

Gang, Li; Sun, Xiao-yi; Xu, Jin-quan; Zhang, Xin-li; Kou, Lu-xin; Jiang, Zhi-hong; Zhang, Lei

2012-02-01

To determine the optimal positive end-expiratory pressure (PEEP) according to inflation and deflation pressure-volume curve (P-V curve) in patients with acute respiratory distress syndrome (ARDS). ARDS models were reproduced in 20 dogs, and they were randomly divided into two groups. In both groups, Levenberg-Marquardt iterative algorithm was employed using software to explore parameters fitting with Boltzmann formula, by which the real inflection point of pressure (Pinf d) in deflation limb or lower inflection point pressure (PLip) in inflation limb on P-V curve were defined. For the control group (inflation curve) P-V curve of PLip + 2 cm H(2)O [1 cm H(2)O = 0.098 kPa] was applied as the best PEEP value. In the experimental group (deflation curve) the Pinf d was taken as the best PEEP value. The heart rate (HR), blood pressure (BP), fingertip pulse oxygen saturation [SpO(2)], static lung compliance (Cst), arterial partial pressure of oxygen [PaO(2)] and arterial partial pressure of carbon dioxide [PaCO(2)] were monitored at 0, 2, 6, 12, 24 and 48 hours. Oxygenation index increased significantly both in control and experimental groups. In experimental group, oxygenation index (mm Hg, 1 mm Hg = 0.133 kPa) of 12, 24 and 48 hours was respectively significantly higher than that of the control group (12 hours: 177.63 ± 8.94 vs. 165.60 ± 8.90, 24 hours: 194.19 ± 10.67 vs. 168.70 ± 10.60, 48 hours: 203.15 ± 13.21 vs. 171.26 ± 9.21, all P deflation P-V curve was better than that of inflation curve.

Environmental lead exposure is associated with visit-to-visit systolic blood pressure variability in the US adults.

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Faramawi, Mohammed F; Delongchamp, Robert; Lin, Yu-Sheng; Liu, Youcheng; Abouelenien, Saly; Fischbach, Lori; Jadhav, Supriya

2015-04-01

The association between environmental lead exposure and blood pressure variability, an important risk factor for cardiovascular disease, is unexplored and unknown. The objective of the study was to test the hypothesis that lead exposure is associated with blood pressure variability. American participants 17 years of age or older from National Health and Nutrition Examination Survey III were included in the analysis. Participants' blood lead concentrations expressed as micrograms per deciliter were determined. The standard deviations of visit-to-visit systolic and diastolic blood pressure were calculated to determine blood pressure variability. Multivariable regression analyses adjusted for age, gender, race, smoking and socioeconomic status were employed. The participants' mean age and mean blood lead concentration were 42.72 years and 3.44 mcg/dl, respectively. Systolic blood pressure variability was significantly associated with environmental lead exposure after adjusting for the effect of the confounders. The unadjusted and adjusted means of visit-to-visit systolic blood pressure variability and the β coefficient of lead exposure were 3.44, 3.33 mcg/dl, β coefficient = 0.07, P variability. Screening adults with fluctuating blood pressure for lead exposure could be warranted.

Efficacy and duration of benazepril plus amlodipine or hydrochlorothiazide on 24-hour ambulatory systolic blood pressure control.

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Jamerson, Kenneth A; Devereux, Richard; Bakris, George L; Dahlöf, Björn; Pitt, Bertram; Velazquez, Eric J; Weir, Matthew; Kelly, Roxzana Y; Hua, Tsushung A; Hester, Allen; Weber, Michael A

2011-02-01

The combination of benazepril plus amlodipine was shown to be more effective than benazepril plus hydrochlorothiazide in reducing cardiovascular events in the Avoiding Cardiovascular Events through Combination Therapy in Patients Living with Systolic Hypertension (ACCOMPLISH) trial. There was a small difference in clinic systolic blood pressure between the treatment arms favoring benazepril plus amlodipine. Ambulatory blood pressure monitoring provides a more rigorous estimate of blood pressure effects. A subset of 573 subjects underwent ambulatory blood pressure monitoring during year 2. Readings were obtained every 20 minutes during a 24-hour period. Between-treatment differences (benazepril plus amlodipine versus benazepril plus hydrochlorothiazide) in mean values were analyzed using ANOVA. Treatment comparisons with respect to categorical variables were made using Pearson's χ². At year 2, the treatment groups did not differ significantly in 24-hour mean daytime or nighttime blood pressures (values of 123.9, 125.9, and 118.1 mm Hg for benazepril plus amlodipine group versus 122.3, 124.1, and 116.9 for the benazepril plus hydrochlorothiazide group), with mean between-group differences of 1.6, 1.8, and 1.2 mm Hg, respectively. Blood pressure control rates (24-hour mean systolic blood pressure <130 mm Hg on ambulatory blood pressure monitoring) were greater than 80% in both groups. Nighttime systolic blood pressure provided additional risk prediction after adjusting for the effects of drugs. The 24-hour blood pressure control was similar in both treatment arms, supporting the interpretation that the difference in cardiovascular outcomes favoring a renin angiotensin system blocker combined with amlodipine rather than hydrochlorothiazide shown in the ACCOMPLISH trial was not caused by differences in blood pressure, but instead intrinsic properties (metabolic or hemodynamic) of the combination therapies.

Decreasing systolic blood pressure and declining mortality rates in an untreated population

DEFF Research Database (Denmark)

Andersen, Ulla O; Marott, Jacob L; Jensen, Gorm B

2011-01-01

The aim of the present study was to evaluate developments in 30 years mortality risk that may be associated with developments in population systolic blood pressure (SBP) and to evaluate possible secular trends in BP-associated mortality risk in the untreated population....

Morning pulse pressure is associated more strongly with elevated albuminuria than systolic blood pressure in patients with type 2 diabetes mellitus: post hoc analysis of a cross-sectional multicenter study.

Science.gov (United States)

Ushigome, Emi; Fukui, Michiaki; Hamaguchi, Masahide; Matsumoto, Shinobu; Mineoka, Yusuke; Nakanishi, Naoko; Senmaru, Takafumi; Yamazaki, Masahiro; Hasegawa, Goji; Nakamura, Naoto

2013-09-01

Recently, focus has been directed toward pulse pressure as a potentially independent risk factor for micro- and macrovascular disease. This study was designed to examine the relationship between pulse pressure taken at home and elevated albuminuria in patients with type 2 diabetes. This study is a post hoc analysis of a cross-sectional multicenter study. Home blood pressure measurements were performed for 14 consecutive days in 858 patients with type 2 diabetes. We investigated the relationship between systolic blood pressure or pulse pressure in the morning or in the evening and urinary albumin excretion using univariate and multivariate analyses. Furthermore, we measured area under the receiver-operating characteristic curve (AUC) to compare the ability to identify elevated albuminuria, defined as urinary albumin excretion equal to or more than 30 mg/g creatinine, of systolic blood pressure or pulse pressure. Morning systolic blood pressure (β=0.339, Ppressure (β=0.378, PAUC for elevated albuminuria in morning systolic blood pressure and morning pulse pressure were 0.668 (0.632-0.705; PAUC of morning pulse pressure was significantly greater than that of morning systolic blood pressure (P=0.040). Our findings implicate that morning pulse pressure is associated with elevated albuminuria in patients with type 2 diabetes, which suggests that lowering morning pulse pressure could prevent the development and progression of diabetic nephropathy. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Prevalence and implications of a difference in systolic blood pressure between one arm and the other in vascular surgical patients.

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Durrand, J W; Batterham, A M; O'Neill, B R; Danjoux, G R

2013-12-01

Inter-arm differences in blood pressure may confound haemodynamic management in vascular surgery. We evaluated 898 patients in the vascular pre-assessment clinic to determine the prevalence of inter-arm differences in systolic and mean arterial pressure, quantify the consequent risk of clinical error in siting monitoring peri-operatively and evaluate systolic inter-arm difference as a predictor of all-cause mortality (median follow-up 49 months). The prevalence of a systolic inter-arm difference ≥ 15 mmHg was 26% (95% CI 23-29%). The prevalence of an inter-arm mean arterial pressure difference ≥ 10 mmHg was 26% (95% CI 23-29%) and 11% (95% CI 9-13%) for a difference ≥ 15 mmHg. Monitoring could be erroneously sited in an arm reading lower for systolic pressure once in every seven to nine patients. The hazard ratio for a systolic inter-arm difference ≥ 15 mmHg vs arm blood pressure differences are common in this population, with a high potential for monitoring errors. Systolic inter-arm difference was not associated with medium-term mortality. [Correction added on 17 October 2013, after first online publication: In the Summary the sentence beginning 'We evaluated 898 patients' was corrected from (median (IQR [range]) follow-up 49 months) to read (median follow up 49 months)]. © 2013 The Association of Anaesthetists of Great Britain and Ireland.

Longitudinal Patterns of Change in Systolic Blood Pressure and Incidence of Cardiovascular Disease: The Atherosclerosis Risk in Communities Study.

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Petruski-Ivleva, Natalia; Viera, Anthony J; Shimbo, Daichi; Muntner, Paul; Avery, Christy L; Schneider, Andrea L C; Couper, David; Kucharska-Newton, Anna

2016-06-01

Elevated blood pressure in midlife contributes significantly to the risk of cardiovascular disease. However, patterns of blood pressure increase may differ among individuals and may result in differential risk. Our goal was to examine the contribution of longitudinal patterns of blood pressure change to incidence of heart failure, coronary heart disease, stroke, and cardiovascular disease mortality. Latent class growth models were used to identify patterns of change in blood pressure across 4 clinical examinations (1987-1998) among 9845 Atherosclerosis Risk in Communities (ARIC) cohort participants (mean age, 53.7 [SD 5.7] years). Patterns of change in systolic blood pressure included slowly and steeply increasing, a decreasing and a sustained elevated blood pressure. Changes in diastolic and mid-blood pressure (½ systolic+½ diastolic) were less pronounced. The association of blood pressure pattern group membership with incidence of clinical outcomes was examined in follow-up from the fourth clinical examination (1996-1998) to December 31, 2011, using Poisson regression models adjusted for demographic and metabolic characteristics, and hypertension medication use. A gradient of rates of all events was observed across the identified patterns. Associations were attenuated after adjustment for covariates. Cumulative systolic blood pressure load, rather than the temporal pattern of change in systolic blood pressure itself, plays a role in determining the risk of cardiovascular disease, in particular, of heart failure and cardiovascular disease mortality, independent of blood pressure level measured at one point in time. © 2016 American Heart Association, Inc.

Validation of attenuation-corrected equilibrium radionuclide angiographic determinations of right ventricular volume: comparison with cast-validated biplane cineventriculography

International Nuclear Information System (INIS)

Dell'Italia, L.J.; Starling, M.R.; Walsh, R.A.; Badke, F.R.; Lasher, J.C.; Blumhardt, R.

1985-01-01

To determine the accuracy of attenuation-corrected equilibrium radionuclide angiographic determinations of right ventricular volumes, the authors initially studied 14 postmortem human right ventricular casts by water displacement and biplane cineventriculography. Biplane cineventriculographic right ventricular cast volumes, calculated by a modification of Simpson's rule algorithm, correlated well with right ventricular cast volumes measured by water displacement (r = .97, y = 8 + 0.88x, SEE = 6 ml). Moreover, the mean volumes obtained by both methods were no different (73 +/- 28 vs 73 +/- 25 ml). Subsequently, they studied 16 patients by both biplane cineventriculography and equilibrium radionuclide angiography. The uncorrected radionuclide right ventricular volumes were calculated by normalizing background corrected end-diastolic and end-systolic counts from hand-drawn regions of interest obtained by phase analysis for cardiac cycles processed, frame rate, and blood sample counts. Attenuation correction was performed by a simple geometric method. The attenuation-corrected radionuclide right ventricular end-diastolic volumes correlated with the cineventriculographic end-diastolic volumes (r = .91, y = 3 + 0.92x, SEE = 27 ml). Similarly, the attenuation-corrected radionuclide right ventricular end-systolic volumes correlated with the cineventriculographic end-systolic volumes (r = .93, y = - 1 + 0.91x, SEE = 16 ml). Also, the mean attenuation-corrected radionuclide end-diastolic and end-systolic volumes were no different than the average cineventriculographic end-diastolic and end-systolic volumes (160 +/- 61 and 83 +/- 44 vs 170 +/- 61 and 86 +/- 43 ml, respectively)

Systolic and Diastolic Left Ventricular Mechanics during and after Resistance Exercise.

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Stöhr, Eric J; Stembridge, Mike; Shave, Rob; Samuel, T Jake; Stone, Keeron; Esformes, Joseph I

2017-10-01

To improve the current understanding of the impact of resistance exercise on the heart, by examining the acute responses of left ventricular (LV) strain, twist, and untwisting rate ("LV mechanics"). LV echocardiographic images were recorded in systole and diastole before, during and immediately after (7-12 s) double-leg press exercise at two intensities (30% and 60% of maximum strength, one-repetition maximum). Speckle tracking analysis generated LV strain, twist, and untwisting rate data. Additionally, beat-by-beat blood pressure was recorded and systemic vascular resistance (SVR) and LV wall stress were calculated. Responses in both exercise trials were statistically similar (P > 0.05). During effort, stroke volume decreased, whereas SVR and LV wall stress increased (P mechanics (P 0.05). Immediately after exercise, systolic LV mechanics returned to baseline levels (P mechanics, but increases diastolic mechanics after exercise, suggesting that resistance exercise has a differential impact on systolic and diastolic heart muscle function. The findings may explain why acute resistance exercise has been associated with reduced stroke volume but chronic exercise training may result in increased LV volumes.

Cardiac systolic function in cirrhotic patients’ candidate of liver trans-plantation compared with control group

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Roya Sattarzadeh-Badkoubeh

2017-02-01

Full Text Available Background: We assessed different systolic cardiac indices to describe left and right ventricular dysfunction in cirrhotic patients before liver transplantation. Methods: In this case-control study, eighty-one consecutive individuals with the confirmed hepatic cirrhosis and candidate for liver transplantation in the Imam Khomeini Hospital between March 2008 and March 2010 were selected. Thirty-two age and gender cross-matched healthy volunteers were also selected as the control group. A detailed two-dimensional and Doppler echocardiography was obtained in all patients and controls performed by the same operator on the day of admission. Results: Dimensions of both left and right atriums as well as left ventricular end-diastolic volume and basal right ventricular dimension in the cirrhotic group were significantly higher than control group. Left ventricular end-systolic dimensions as well as aortic annulus diameter were not different between the two study groups. Left ventricular outflow tract velocity time integral, isovolumic pre-ejection time, isovolumic relaxation time, stroke volume, left ventricular ejection fraction, IVCT+IVRT+ET, systolic velocity of tricuspid annulus, systolic velocity of basal segment of RV free wall, systolic velocity of basal segment of septal wall, peak strain of septal margin (base, peak strain of septal margin (midpoint, peak strain of lateral margin (midpoint, strain rate of septal margin (base, strain rate of septal margin (midpoint, strain rate of lateral margin (base, strain rate of lateral margin (midpoint, Tei index (left and right ventricles, systolic time interval and tricuspid annular plane systolic excursion were higher in cirrhotic group, significantly, (P< 0.05. Left ventricular ejection time and systolic velocity of mid segment of lateral wall were lower in cirrhotic group, significantly, (P< 0.05. Conclusion: In this study, the effects of liver on heart were volume overload, hyperdynamic state and

Left ventricular remodeling and change of systolic function after closure of patent ductus arteriosus in adults: device and surgical closure.

Science.gov (United States)

Jeong, Young-Hoon; Yun, Tae-Jin; Song, Jong-Min; Park, Jung-Jun; Seo, Dong-Man; Koh, Jae-Kon; Lee, Se-Whan; Kim, Mi-Jeong; Kang, Duk-Hyun; Song, Jae-Kwan

2007-09-01

Left ventricular (LV) remodeling and predictors of LV systolic function late after closure of patent ductus arteriosus (PDA) in adults remain to be clearly demonstrated. In 45 patients with PDA, including 28 patients who received successful occlusion using the Amplatzer device (AD group) (AGA, Golden Valley, MN) and 17 patients who received surgical closure (OP group), echocardiography studies were performed before closure and 1 day (AD group) or within 7 days (OP group) after closure, and then were repeated at > or = 6 months (17 +/- 13 months). In both groups, LV ejection fraction (EF) and end-diastolic volume index were significantly decreased immediately after closure, whereas end-systolic volume index did not change. During the long-term follow-up period, end-systolic as well as end-diastolic volume indices decreased significantly in both groups and LV EF recovered compared to the immediate postclosure state. However, LV EF remained low compared to the preclosure state. Five patients (11.1%) including 3 patients in the AD group and 2 patients in the OP group showed persistent late LV systolic dysfunction (EF or = 62% had a sensitivity of 72% and a specificity of 83% for predicting late normal LV EF after closure. Left ventricular EF remains low late after PDA closure compared with preclosure state in adults. Preclosure LV EF is the best index to predict late postclosure LV EF.

Role of myocardial hypertrophy on acute and chronic right ventricular performance in relation to chronic volume overload in a porcine model: relevance for the surgical management of tetralogy of Fallot.

Science.gov (United States)

Bove, Thierry; Vandekerckhove, Kristof; Bouchez, Stefaan; Wouters, Patrick; Somers, Pamela; Van Nooten, Guido

2014-06-01

The age for correction of tetralogy of Fallot has progressively declined to the postnatal period, often despite an increased rate of transannular patch repair. However, the long-term effect of premature exposure to chronic pulmonary insufficiency on the right ventricle remains unknown. On the basis of the relationship between the duration of pressure overload and age, the role of previous pressure load-related hypertrophy on right ventricular (RV) performance after chronic volume overload was investigated in a porcine model. RV hypertrophy (RVH), induced by pulmonary artery banding, was studied in pigs with (RVH plus pulmonary insufficiency [PI]) and without (RVH) subsequent PI. The effect of volume overload was compared between these 2 groups and pigs without RVH but with PI and controls (sham). Both acute and chronic effects on RV function were studied using conductance technology and validated using echocardiography. After chronic volume overload, the end-systolic and end-diastolic volumes were smaller in the RVH+PI group than in the PI group, including a lower pulmonary regurgitation fraction (25% ± 5% vs 35% ± 5%; P = .002). RVH resulted in better preserved systolic function, confirmed by an increased preload recruitable stroke work slope (14.7 ± 1.8 vs 9.3 ± 1.3 Mw.s/mL; P = .025) and higher RV ejection fraction (51% ± 3% vs 45% ± 4%; P = .05). Myocardial stiffness was impaired in the RVH+PI group versus the PI group (β, 0.19 ± 0.03 vs 0.12 ± 0.02 mL(-1); P = .001), presenting restrictive physiology only in the condition associating RVH and PI. The results of the present study have demonstrated that RVH attenuates the RV remodeling process related to chronic PI. It enables better preservation of contractility but at the cost of sustained diastolic impairment. These findings might help to determine the timing and strategy for repair of tetralogy of Fallot when RV outflow tract morphology indicates a definite need for transannular reconstruction

Modification of a Volume-Overload Heart Failure Model to Track Myocardial Remodeling and Device-Related Reverse Remodeling

Science.gov (United States)

Tuzun, Egemen; Bick, Roger; Kadipasaoglu, Cihan; Conger, Jeffrey L.; Poindexter, Brian J.; Gregoric, Igor D.; Frazier, O. H.; Towbin, Jeffrey A.; Radovancevic, Branislav

2011-01-01

Purpose. To provide an ovine model of ventricular remodeling and reverse remodeling by creating congestive heart failure (CHF) and then treating it by implanting a left ventricular assist device (LVAD). Methods. We induced volume-overload heart failure in 2 sheep; 20 weeks later, we implanted an LVAD and assessed recovery 11 weeks thereafter. We examined changes in histologic and hemodynamic data and levels of cellular markers of CHF. Results. After CHF induction, we found increases in LV end-diastolic pressure, LV systolic and diastolic dimensions, wall thickness, left atrial diameter, and atrial natriuretic protein (ANP) and endothelin-1 (ET-1) levels; β-adrenergic receptor (BAR) and dystrophin expression decreased markedly. Biopsies confirmed LV remodeling. After LVAD support, LV systolic and diastolic dimensions, wall thickness, and mass, and ANP and ET-1 levels decreased. Histopathologic and hemodynamic markers improved, and BAR and dystrophin expression normalized. Conclusions. We describe a successful sheep model for ventricular and reverse remodeling. PMID:22347659

Prognostic value of systolic mitral annular velocity measured with Doppler tissue imaging in patients with chronic heart failure caused by left ventricular systolic dysfunction

Science.gov (United States)

Nikitin, N P; Loh, P H; de Silva, R; Ghosh, J; Khaleva, O Y; Goode, K; Rigby, A S; Alamgir, F; Clark, A L; Cleland, J G F

2006-01-01

Objective To assess the prognostic value of various conventional and novel echocardiographic indices in patients with chronic heart failure (CHF) caused by left ventricular (LV) systolic dysfunction. Methods 185 patients with a mean (SD) age of 67 (11) years with CHF and LV ejection fraction < 45% despite optimal pharmacological treatment were prospectively enrolled. The patients underwent two dimensional echocardiography with tissue harmonic imaging to assess global LV systolic function and obtain volumetric data. Transmitral flow was assessed with conventional pulse wave Doppler. Systolic (Sm), early, and late diastolic mitral annular velocities were measured with the use of colour coded Doppler tissue imaging. Results During a median follow up of 32 months (range 24–38 months in survivors), 34 patients died and one underwent heart transplantation. Sm velocity (hazard ratio (HR) 0.648, 95% confidence interval (CI) 0.463 to 0.907, p  =  0.011), diastolic arterial pressure (HR 0.965, 95% CI 0.938 to 0.993, p  =  0.015), serum creatinine (HR 1.006, 95% CI 1.001 to 1.011, p  =  0.023), LV ejection fraction (HR 0.945, 95% CI 0.899 to 0.992, p  =  0.024), age (HR 1.035, 95% CI 1.000 to 1.071, p  =  0.052), LV end systolic volume index (HR 1.009, 95% CI 0.999 to 1.019, p  =  0.067), and restrictive pattern of transmitral flow (HR 0.543, 95% CI 0.278 to 1.061, p  =  0.074) predicted the outcome of death or transplantation on univariate analysis. On multivariate analysis, only Sm velocity (HR 0.648, 95% CI 0.460 to 0.912, p  =  0.013) and diastolic arterial pressure (HR 0.966, 95% CI 0.938 to 0.994, p  =  0.016) emerged as independent predictors of outcome. Conclusions In patients with CHF and LV systolic dysfunction despite optimal pharmacological treatment, the strongest independent echocardiographic predictor of prognosis was Sm velocity measured with quantitative colour coded Doppler tissue

Comparing the Efficacy of Tadalafil Versus Placebo on Pulmonary Artery Systolic Pressure and Right Ventricular Function in Patients with Beta-Thalassaemia Intermedia.

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Jalalian, Rozita; Moghadamnia, Ali Akbar; Tamaddoni, Ahmad; Khafri, Soraya; Iranian, Mohammadreza

2017-07-01

Conventional oral therapies in the management of pulmonary hypertension in people without haemoglobinopathies are of limited value in thalassaemia patients because of toxicity and poor effectiveness. This study was conducted to assess the effect of tadalafil on pulmonary artery pressure and right ventricular systolic function in patients with beta-thalassaemia intermedia. Forty-four patients with beta-thalassaemia intermedia with pulmonary hypertension based on transthoracic echocardiography (TTE) were entered in the study. Patients with hepatic or renal insufficiency and also patients who were treated with organic nitrates or alpha-blockers were excluded. The patients were randomly divided into two groups (n=22) and they were treated for six weeks with tadalafil (40mg daily) or placebo. The pulmonary artery systolic pressure (PASP), tricuspid regurgitation velocity (TRV) and parameters related to systolic function of the right ventricle were measured by the TTE before and after treatment. Significant improvement in TRV (3.02±0.02 m/s-2.52±0.06 m/s), PASP (45.31±0.66 mmHg-34.26±1.15mmHg) and parameters related to systolic function of the right ventricle were observed in the group who received tadalafil compared to placebo (pintermedia. Likewise, tadalafil improved right ventricular systolic function in the patients. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Systolic blood pressure reactivity during submaximal exercise and acute psychological stress in youth

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Background: Studies in youth show an association between systolic blood-pressure (SBP) reactivity to acute psychological stress and carotid artery intima-media thickness (CIMT). However, it has not yet been determined whether SBP reactivity during submaximal exercise is also associated with CIMT i...

Central aortic systolic blood pressure can predict prolonged QTc duration better than brachial artery systolic blood pressure in rural community residents.

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Huang, Yuqing; Tang, Songtao; Chen, Ji-Yan; Huang, Cheng; Li, Jie; Cai, An-Ping; Feng, Yingqing

2018-01-01

Previous studies have suggested that prolonged electrocardiogram QTc duration was independent risk factor for both increased cardiovascular and all-cause mortality, but there was no dating about the relationship between central aortic systolic blood pressure (CASP) and QTc duration. The aim of this study was to analyze the relationship between CASP and QTc duration, and assess whether CASP can predict prolonged QTc duration more than BSBP. A total of 500 patients were enrolled in this study, central and brachial aortic blood pressure and electrocardiogram QTc duration were measured. Pearson correlation was assessed for determining the associations of QTc duration with clinical conditions. Multivariate logistic regression analyses were performed to determine the independent predictor of prolonged QTc duration. Receiver operating characteristic (ROC) curve was used to evaluate the utility of blood pressure for prolonged QTc duration. We found QTc durations were significantly positive with CASP (r = 0.308, p AUC: 0.771 vs. 0.646, p < 0.001) BSBP. Our results suggested that the non-invasive CASP is independently correlated with QTc duration, and CASP can predict prolonged QTc duration more than BSBP.

Lack of association between systolic blood pressure and blood viscosity in normotensive healthy subjects.

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Irace, Concetta; Carallo, Claudio; Scavelli, Faustina; Loprete, Antonio; Merante, Valentina; Gnasso, Agostino

2012-01-01

A direct relationship between blood pressure and viscosity has frequently been reported, although clear data are not available. To better understand the relationship between these two variables, we evaluated blood viscosity and blood pressure in a group of healthy subjects without cardiovascular risk factors. Healthy subjects were selected from participants in a campaign of prevention of cardiovascular disease (n = 103). They underwent blood sampling for measurement of plasma and blood viscosity, haematocrit, blood lipids and glucose. The quantity and distribution of body fat was assessed by body mass index and waist/hip ratio, respectively. Systolic blood pressure (SBP) correlated significantly with age (r = 0.222) and waist/hip ratio (r = 0.374). Diastolic blood pressure (DBP) correlated significantly with waist/hip ratio (r = 0.216), haematocrit (r = 0.333) and blood viscosity (r = 0.258). Multiple linear regression analyses demonstrated that the only variable significantly associated with SBP was age, while haematocrit was the only variable significantly associated with DBP. Blood viscosity was closely related to waist/hip ratio. These findings show that SBP, in healthy subjects, is not influenced by haematocrit and blood viscosity. In contrast, DBP is related to the values of haematocrit. Among classical cardiovascular risk factors, waist/hip ratio is closely related to blood viscosity.

Exercise capacity in young adults with hypertension and systolic blood pressure difference between right arm and leg after repair of coarctation of the aorta.

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Instebø, Arne; Norgård, Gunnar; Helgheim, Vegard; Røksund, Ola Drange; Segadal, Leidulf; Greve, Gottfried

2004-10-01

Coarctation of the aorta represents 5-7% of congenital heart defects. Symptoms and prognosis depend on the degree of stenosis, age at surgery, surgical method and the presence of other heart defects. Postoperative complications are hypertension, restenosis and an abnormal blood pressure response during exercise. This study includes 41 patients, 15-40 years old, operated in the period 1975-1996. All were exercised on a treadmill until maximal oxygen consumption was achieved. Blood pressure was measured in the right arm and leg before and immediately after exercise, and in the right arm during exercise. Oxygen consumption was monitored and we defined an aerobic phase, an isocapnic buffering phase and a hypocapnic hyperventilation phase. The resting systolic blood pressure correlates with the resting systolic blood pressure difference between right arm and leg. A resting systolic blood pressure difference between the right arm and leg of 0.13 kPa (1 mmHg) to 2.67 kPa (20 mmHg) corresponds with a slight increase in resting systolic blood pressure. This rise in blood pressure increases the aerobic phase of the exercise test, helping the patients to achieve higher maximal oxygen consumption. A resting systolic blood pressure difference of more than 2.67 kPa (20 mmHg) corresponds with severe hypertension and causes reduction in the aerobic phase and maximal oxygen consumption. Resting systolic blood pressure and resting systolic blood pressure difference between the right arm and leg are not indicators for blood pressure response during exercise. Exercise testing is important to reveal exercise-induced hypertension and to monitor changes in transition from aerobic to anaerobic exercise and limitation to exercise capacity.

Benazepril combined with either amlodipine or hydrochlorothiazide is more effective than monotherapy for blood pressure control and prevention of end-organ injury in hypertensive Dahl rats.

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Zhou, Ming-Sheng; Jaimes, Edgar A; Raij, Leopoldo

2006-07-01

We studied the effect of hydrochlorothiazide (HCTZ), the angiotensin-converting enzyme inhibitor benazepril, the calcium channel blocker amlodipine, or a combination of benazepril/amlodipine or benazepril/HCTZ on systolic blood pressure (BP) and end-organ injury (left ventricular hypertrophy, proteinuria, and endothelium-dependent relaxation to acetylcholine) in hypertensive Dahl salt-sensitive rats fed either a normal-salt (0.5% NaCl) or high-salt (4% NaCl) diet for 6 weeks. Rats fed a high-salt diet developed hypertension and significant end-organ injury. Monotherapy with HCTZ (75 mg/L in drinking water) or amlodipine (10 mg/kg/day by gavage) reduced systolic BP and proteinuria; benazepril (40 mg/kg/day by gavage) decreased proteinuria without significantly lowering systolic BP. In rats receiving a high-salt diet, only HCTZ reduced left ventricular hypertrophy, whereas endothelium-dependent relaxation was improved by amlodipine and benazepril but not by HCTZ. Combining benazepril with either amlodipine or HCTZ dramatically reduced systolic BP and end-organ injury. These data clearly support clinical studies suggesting that combination therapy is more effective than monotherapy for systolic BP control and prevention of end-organ injury. Complementary mechanisms of action of agents from different antihypertensive classes appear to facilitate the greater benefit on BP and end-organ injury.

How well can blood pressure be controlled? Progress report on the Systolic Hypertension in Europe Follow-Up Study (Syst-Eur 2

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Sarti Cinzia

2001-10-01

Full Text Available Abstract Background The randomised, double-blind, placebo-controlled Systolic Hypertension in Europe trial (Syst-Eur 1 proved that blood pressure (BP lowering therapy starting with nitrendipine reduces the risk of cardiovascular complications in elderly patients with isolated systolic hypertension. In an attempt to confirm the safety of long-term antihypertensive therapy based on a dihydropyridine, the Syst-Eur patients remained in open follow-up after the end of Syst-Eur 1. This paper presents the second progress report of this follow-up study (Syst-Eur 2. It describes BP control and adherence to study medications. Methods After the end of Syst-Eur 1 all patients, treated either actively or with placebo, were invited either to continue or to start antihypertensive treatment with the same drugs as previously used in the active treatment arm. In order to reach the target BP (sitting SBP Results Of the 3787 eligible patients, 3516 (93% entered Syst-Eur 2. At the last available visit, 72% of the patients were taking nitrendipine. SBP/DBP at entry in Syst-Eur 2 averaged 160/83 mmHg in the former placebo group and 151/80 mmHg in the former active-treatment group. At the last follow-up visit SBP/DBP in the patients previously randomised to placebo or active treatment had decreased by 16/5 mmHg and 7/5 mmHg, respectively. The target BP was reached by 74% of the patients. Conclusion Substantial reductions in systolic BP may be achieved in older patients with isolated systolic hypertension with a treatment strategy starting with the dihydropyridine calcium-channel blocker, nitrendipine, with the possible addition of enalapril and/or hydrochlorothiazide.

Is hydrotherapy an appropriate form of exercise for elderly patients with biventricular systolic heart failure?

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Sveälv, Bente Grüner; Täng, Margareta Scharin; Cider, Åsa

2012-01-01

Hydrotherapy (exercise in warm water) is considered to be a safe and beneficial method to use in the rehabilitation of stable heart failure patients, but there is little information on the effect of the increased venous return and enhanced preload in elderly patients with biventricular heart failure. We present a case of an elderly man who was recruited to participate in a hydrotherapy study. We compared echocardiographic data during warm water immersion with land measurements, and observed increases in stroke volume from 32 mL (land) to 42 mL (water), left ventricular ejection fraction from 22% to 24%, left ventricular systolic velocity from 4.8 cm/s to 5.0 cm/s and left atrioventricular plane displacement from 2.1 mm to 2.2 mm. By contrast, right ventricular systolic velocity decreased from 11.2 cm/s to 8.4 cm/s and right atrioventricular plane displacement from 8.1 mm to 4.7 mm. The tricuspid pressure gradient rose from 18 mmHg on land to 50 mmHg during warm water immersion. Thus, although left ventricular systolic function was relatively unaffected during warm water immersion, we observed a decrease in right ventricular function with an augmented right ventricular pressure. We recommend further investigations to observe the cardiac effect of warm water immersion on patients with biventricular systolic heart failure and at risk of elevated right ventricular pressure. PMID:23341846

NSAID-antihypertensive drug interactions: Which outpatients are at risk for a rise in systolic blood pressure?

NARCIS (Netherlands)

Floor-Schreudering, Annemieke; De Smet, Peter Agm; Buurma, Henk; Kramers, Cornelis; Tromp, P. Chris; Belitser, Svetlana V.; Bouvy, Marcel L.

2015-01-01

Background: Management guidelines for drug-drug interactions between non-steroidal anti-inflammatory drugs (NSAIDs) and antihypertensives recommend blood pressure monitoring in hypertensive patients. We measured the short-term effect of initiating NSAIDs on systolic blood pressure (SBP) in users of

NSAID-antihypertensive drug interactions: which outpatients are at risk for a rise in systolic blood pressure?

NARCIS (Netherlands)

Floor-Schreudering, A.; Smet, P.A.G.M. de; Buurma, H.; Kramers, C.; Tromp, P.C.; Belitser, S.V.; Bouvy, M.L.

2015-01-01

BACKGROUND: Management guidelines for drug-drug interactions between non-steroidal anti-inflammatory drugs (NSAIDs) and antihypertensives recommend blood pressure monitoring in hypertensive patients. We measured the short-term effect of initiating NSAIDs on systolic blood pressure (SBP) in users of

Influence of age on left ventricular performance during exercise in normal Japanese subject

International Nuclear Information System (INIS)

Konishi, Tokuji; Koyama, Takao; Aoki, Toshikazu; Makino, Katsutoshi; Yamamuro, Masashi; Nakai, Kyudayu; Nakamura, Masayuki; Nakano, Takeshi.

1990-01-01

To assess the effects of age on left ventricular performance, multistage supine ergometer exercise radionuclide ventriculography (RNV) was performed in 92 normal subjects. The subjects ranged in age from 24 to 86 years and were free of cardiopulmonary disease and diabetes. Age-related changes in exercise duration, left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), cardiac output (CO) left ventricular ejection fraction (LVEF), left ventricular dv/dt, systolic and diastolic time indexes of dv/dt, and peak systolic pressure/left ventricular end-systolic volume (PSP/LVESV) were analyzed at rest and during the peak exercise stage. Age-related decrease in LVEDV and peak diastolic dv/dt were significant at rest. The time indexes of ECG R to peak systolic dv/dt and time of end-systole to peak diastolic dv/dt also were prolonged with age. Both maximum heart rate and exercise duration were shown to decline with age. No age-related difference was observed in LVESV, LVEF or PSP/LVESV either at rest or during exercise. However, the change of LVEF and LVESV during exercise was less in subjects aged 60 or more. These results indicate decreased left ventricular function during exercise in elderly subjects. (author)

Prevalence of systolic inter-arm differences in blood pressure for different primary care populations: systematic review and meta-analysis.

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Clark, Christopher E; Taylor, Rod S; Shore, Angela C; Campbell, John L

2016-11-01

Various prevalence figures have been reported for inter-arm differences in blood pressure (IAD); variation may be explained by differing population vascular risk and by measurement method. To review the literature to derive robust estimates of IAD prevalence relevant to community populations. Systematic review and meta-analysis. MEDLINE, Embase, and CINAHL were searched for cross-sectional studies likely to represent general or primary care populations, reporting prevalence of IAD and employing a simultaneous method of measurement. Using study-level data, pooled estimates of mean prevalence of systolic IADs were calculated and compared using a random effects model. Eighty IAD studies were identified. Sixteen met inclusion criteria: pooled estimates of prevalence for systolic IAD ≥10 mmHg were 11.2% (95% confidence interval [CI] = 9.1 to 13.6) in hypertension, 7.4% (95% CI = 5.8 to 9.2) in diabetes, and 3.6% (95% CI = 2.3 to 5.0) for a general adult population (Pdifferences). Differences persisted for higher cut-off values. Prevalences were lower for East Asian than for Western populations and were overestimated by sequential measurement where this could be compared with simultaneous measurement within studies (relative risk for IAD: 2.9 [95% CI = 2.1 to 4.1]). Studies with higher mean absolute systolic pressures had higher prevalences for a systolic IAD ≥10 mmHg (P = 0.04). Prevalences of IADs rise in relation to underlying cardiovascular comorbidities of the population studied, and are overestimated threefold when sequential measurement is used. Population-specific variation in prevalences of IAD should be taken into account in delivering clinical care and in planning future studies. © British Journal of General Practice 2016.

Long-term L-Triiodothyronine (T3) treatment in stable systolic heart failure patients

DEFF Research Database (Denmark)

Holmager, Pernille; Schmidt, Ulla; Mark, Peter

2015-01-01

%, range: 37-52 and serum T3 levels 1·4 nmol/l (0·9-1·6). The T3 dose was 20 μg per day (10-40). TSH levels did not change between groups, whereas serum T3 levels increased in the active arm. Cardiac function as measured by LVEF, end-diastolic and end-systolic volumes and cardiac output did not change...... during T3-treatment and neither did the neurohormonal profile. There were no side-effects in terms of cardiac arrhythmias and no change in resting heart rate. CONCLUSIONS: This study does not support the hypothesis that oral T3 treatment might be beneficial to patients with chronic, stable systolic HF...

THE EFFECTIVENESS OF CHRONOTHERAPY IN HYPERTENSIVE PATIENTS WITH AN INSUFFICIENT DEGREE OF SLEEP-TIME SYSTOLIC BLOOD PRESSURE DECLINE

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Petrenko O. V.

2017-12-01

Full Text Available Blood pressure (BP circadian rhythm violation, manifested as an insufficient degree of its sleep-time relative decline, is an independent cardiovascular risk factor. The main method of the correction is chronotherapeutic approach, when at least one antihypertensive drug is taken at bedtime. However, most researchers focus on normalizing the daily profile of systolic blood pressure (SBP and do not pay enough attention to changes in the daily profile of diastolic blood pressure (DBP and blood pressure in general. The aim of the study was to evaluate the influence of the chronotherapeutic approach on the SBP and DBP levels and the DBP daily profile in hypertensive patients with an insufficient degree of sleep-time relative SBP decline. The study included 12 patients with arterial hypertension (AH with an insufficient degree of sleep-time relative SBP decline. Participants were divided into two groups: group 1 included patients who take at least one antihypertensive drug at bedtime, group 2 – patients who take all antihypertensive drugs in the morning. All patients underwent 24-hour blood pressure monitoring using the computer system «Cardiosens» (KhAI Medica, Ukraine, with the oscillometric method of BP measuring when enrolling in the study and after 3 months. The type of SBP and DBP diurnal profile, the mean values of SBP, DBP and hyperbaric indices were determined and compared between groups 1 and 2 at each visit, as well as within groups between visits. The results showed that the SBP daily profile normalization in patients with insufficient degree of sleep-time relative SBP decline from group 2 was achieved only in 11 % of cases, and in group 1 SBP and DBP daily profile normalized in 1/3 patients. In some patients from group 2 SBP and DBP daily profile converted into the overdipper type, while in group 1 overdippers did not appear at the end of the study. It was concluded that conversion of daily DBP profile to overdipper as a consequence

Validity of Some Anthropometric Indicators in the Prediction of High Systolic Blood Pressure among Indian Adolescents

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Shobha Rao

2008-01-01

Full Text Available Background In view of the increasing prevalence of obesity in children, it is necessary to investigate the relative performance of different indicators used for its assessment and health consequences. Objectives To examine concordance between various indicators used for assessing obesity among adolescents and to examine their ability to predict risk of high systolic blood pressure. Design Cross-sectional study, from two schools catering to affluent class. Subjects Children in age 9–16 yr (n = 1146 boys and 1036 girls. Measurements Body weight, height, skinfold thickness at triceps (TSFT and body fat percent by trained investigators and blood pressure measurement by a pediatrician using sphygmomanometer. Results Prevalence of overweight was lowest with criterion of TSFT (11.7% in boys; 7.6% in girls and was highest using criterion of body fat percent (53.7% in boys and 28.4% in girls. Body mass index (BMI had high significant correlation with each of the indicator and with systolic blood pressure (SBP as well, in both sexes. All the indicators with conventional cut offs showed poor sensitivity for predicting high SBP. However, receiver operating characteristics (ROC cut-offs improved sensitivity considerably, but the values were much lower compared to conventional cut-offs. Conclusions There is considerable disparity in the estimates of overweight children obtained by different indicators. Lower values of ROC cut-offs highlights the need for population specific customized classification systems for assessing obesity in view of the probable population differences in relative risks of non-communicable adult diseases.

Effects of recruitment maneuver and positive end-expiratory pressure on respiratory mechanics and transpulmonary pressure during laparoscopic surgery.

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Cinnella, Gilda; Grasso, Salvatore; Spadaro, Savino; Rauseo, Michela; Mirabella, Lucia; Salatto, Potito; De Capraris, Antonella; Nappi, Luigi; Greco, Pantaleo; Dambrosio, Michele

2013-01-01

The authors tested the hypothesis that during laparoscopic surgery, Trendelenburg position and pneumoperitoneum may worsen chest wall elastance, concomitantly decreasing transpulmonary pressure, and that a protective ventilator strategy applied after pneumoperitoneum induction, by increasing transpulmonary pressure, would result in alveolar recruitment and improvement in respiratory mechanics and gas exchange. In 29 consecutive patients, a recruiting maneuver followed by positive end-expiratory pressure 5 cm H(2)O maintained until the end of surgery was applied after pneumoperitoneum induction. Respiratory mechanics, gas exchange, blood pressure, and cardiac index were measured before (T(BSL)) and after pneumoperitoneum with zero positive end-expiratory pressure (T(preOLS)), after recruitment with positive end-expiratory pressure (T(postOLS)), and after peritoneum desufflation with positive end-expiratory pressure (T(end)). Esophageal pressure was used for partitioning respiratory mechanics between lung and chest wall (data are mean ± SD): on T(preOLS), chest wall elastance (E(cw)) and elastance of the lung (E(L)) increased (8.2 ± 0.9 vs. 6.2 ± 1.2 cm H(2)O/L, respectively, on T(BSL); P = 0.00016; and 11.69 ± 1.68 vs. 9.61 ± 1.52 cm H(2)O/L on T(BSL); P = 0.0007). On T(postOLS), both chest wall elastance and E(L) decreased (5.2 ± 1.2 and 8.62 ± 1.03 cm H(2)O/L, respectively; P = 0.00015 vs. T(preOLS)), and Pao(2)/inspiratory oxygen fraction improved (491 ± 107 vs. 425 ± 97 on T(preOLS); P = 0.008) remaining stable thereafter. Recruited volume (the difference in lung volume for the same static airway pressure) was 194 ± 80 ml. Pplat(RS) remained stable while inspiratory transpulmonary pressure increased (11.65 + 1.37 cm H(2)O vs. 9.21 + 2.03 on T(preOLS); P = 0.007). All respiratory mechanics parameters remained stable after abdominal desufflation. Hemodynamic parameters remained stable throughout the study. In patients submitted to laparoscopic surgery in

Ambulatory blood pressure profiles in familial dysautonomia.

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Goldberg, Lior; Bar-Aluma, Bat-El; Krauthammer, Alex; Efrati, Ori; Sharabi, Yehonatan

2018-02-12

Familial dysautonomia (FD) is a rare genetic disease that involves extreme blood pressure fluctuations secondary to afferent baroreflex failure. The diurnal blood pressure profile, including the average, variability, and day-night difference, may have implications for long-term end organ damage. The purpose of this study was to describe the circadian pattern of blood pressure in the FD population and relationships with renal and pulmonary function, use of medications, and overall disability. We analyzed 24-h ambulatory blood pressure monitoring recordings in 22 patients with FD. Information about medications, disease severity, renal function (estimated glomerular filtration, eGFR), pulmonary function (forced expiratory volume in 1 s, FEV1) and an index of blood pressure variability (standard deviation of systolic pressure) were analyzed. The mean (± SEM) 24-h blood pressure was 115 ± 5.6/72 ± 2.0 mmHg. The diurnal blood pressure variability was high (daytime systolic pressure standard deviation 22.4 ± 1.5 mmHg, nighttime 17.2 ± 1.6), with a high frequency of a non-dipping pattern (16 patients, 73%). eGFR, use of medications, FEV1, and disability scores were unrelated to the degree of blood pressure variability or to dipping status. This FD cohort had normal average 24-h blood pressure, fluctuating blood pressure, and a high frequency of non-dippers. Although there was evidence of renal dysfunction based on eGFR and proteinuria, the ABPM profile was unrelated to the measures of end organ dysfunction or to reported disability.

No significant effect of angiotensin II receptor blockade on intermediate cardiovascular end points in hemodialysis patients

DEFF Research Database (Denmark)

Peters, Christian Daugaard; Kjaergaard, Krista D; Jensen, Jens D

2014-01-01

Agents blocking the renin-angiotensin-aldosterone system are frequently used in patients with end-stage renal disease, but whether they exert beneficial cardiovascular effects is unclear. Here the long-term effects of the angiotensin II receptor blocker, irbesartan, were studied in hemodialysis......, and residual renal function. Brachial blood pressure decreased significantly in both groups, but there was no significant difference between placebo and irbesartan. Use of additional antihypertensive medication, ultrafiltration volume, and dialysis dosage were not different. Intermediate cardiovascular end...... points such as central aortic blood pressure, carotid-femoral pulse wave velocity, left ventricular mass index, N-terminal brain natriuretic prohormone, heart rate variability, and plasma catecholamines were not significantly affected by irbesartan treatment. Changes in systolic blood pressure during...

Double product and end-organ damage in African and Caucasian men: the SABPA study.

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Schultz, A J; Schutte, A E; Schutte, R

2013-08-10

Increasing urbanisation in sub-Saharan African countries is causing a rapid increase in cardiovascular disease. Evidence suggests that Africans have higher blood pressures and a higher prevalence of hypertension-related cardiovascular morbidity and mortality, compared to Caucasians. We investigated double product (systolic blood pressure × heart rate), a substantial measure of cardiac workload, as a possible cardiovascular risk factor in African and Caucasian men. The study consisted of 101 urbanised African and 101 Caucasian male school teachers. We measured 24h ambulatory blood pressure and the carotid cross-sectional wall area, and determined left ventricular hypertrophy electrocardiographically by means of the Cornell product. Urinary albumin and creatinine were analysed to obtain the albumin-to-creatinine ratio. Africans had higher 24h, daytime and nighttime systolic- and diastolic blood pressure, heart rate and resultant double product compared to the Caucasians. In addition, markers of end-organ damage, albumin-to-creatinine ratio and left ventricular hypertrophy were higher in the Africans while cross-sectional wall area did not differ. In Africans after single partial and multiple regression analysis, 24h systolic blood pressure, but not double product or heart rate, correlated positively with markers of end-organ damage (cross-sectional wall area: β=0.398, P=0.005; left ventricular hypertrophy: β=0.455, Pproduct may not be a good marker of increased cardiovascular risk when compared to systolic blood pressure in African and Caucasian men. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Effect of hematocrit and systolic blood pressure on cerebral blood flow in newborn infants

International Nuclear Information System (INIS)

Younkin, D.P.; Reivich, M.; Jaggi, J.L.; Obrist, W.D.; Delivoria-Papadopoulos, M.

1987-01-01

The effects of hematocrit and systolic blood pressure on cerebral blood flow were measured in 15 stable, low birth weight babies. CBF was measured with a modification of the xenon-133 ( 133 Xe) clearance technique, which uses an intravenous bolus of 133 Xe, an external chest detector to estimate arterial 133 Xe concentration, eight external cranial detectors to measure cephalic 133 Xe clearance curves, and a two-compartmental analysis of the cephalic 133 Xe clearance curves to estimate CBF. There was a significant inverse correlation between hematocrit and CBF, presumably due to alterations in arterial oxygen content and blood viscosity. Newborn CBF varied independently of systolic blood pressure between 60 and 84 mm Hg, suggesting an intact cerebrovascular autoregulatory mechanism. These results indicate that at least two of the factors that affect newborn animal CBF are operational in human newborns and may have important clinical implications

Effect of atrial systole on canine and porcine coronary blood flow.

Science.gov (United States)

Bellamy, R F

1981-09-01

A feature of phasic coronary flow patterns recorded in conscious chronically instrumented dogs is the atrial cove--a transient depression of arterial flow that occurs during atrial systole. The association between the hemodynamic effects of atrial systole and the atrial cove was studied in anesthetized dogs and pigs with complete heart block. Many atrial coves are available for study in these preparations because atrial activity continues unabated during the diastolic ventricular arrest that follows cessation of electrical pacing. The effect of atrial systole is to translate the pressure-flow relation found during diastole to a higher intercept pressure without change in slope. The increase in the intercept pressure equals the increase in intramyocardial pressure measured with microtransducers embedded in the left ventricular wall. The decrement in flow during the atrial cove is a direct function of the change in intramyocardial pressure and an inverse function of coronary vascular resistance. Each atrial systole is associated with a forward flow transient in the coronary veins, the peak of which occurs at the same instant as does the nadir of atrial flow. These data suggest that the coronary vessels are acting as collapsible tubes and that the waterfall model of the coronary circulation is applicable. The following sequence is proposed to account for the atrial cove. Atrial systole ejects a bolus of blood into the left ventricle increasing both ventricular cavity and intramyocardial pressures. The increase in intramyocardial pressure raises the back pressure opposing coronary flow, reducing the arterial perfusion pressure gradient and causing flow to fall.

Electrocardiograph-gated single photon emission computed tomography radionuclide angiography presents good interstudy reproducibility for the quantification of global systolic right ventricular function.

Science.gov (United States)

Daou, Doumit; Coaguila, Carlos; Vilain, Didier

2007-05-01

Electrocardiograph-gated single photon emission computed tomography (SPECT) radionuclide angiography provides accurate measurement of right ventricular ejection fraction and end-diastolic and end-systolic volumes. In this study, we report the interstudy precision and reliability of SPECT radionuclide angiography for the measurement of global systolic right ventricular function using two, three-dimensional volume processing methods (SPECT-QBS, SPECT-35%). These were compared with equilibrium planar radionuclide angiography. Ten patients with chronic coronary artery disease having two SPECT and planar radionuclide angiography acquisitions were included. For the right ventricular ejection fraction, end-diastolic volume and end-systolic volume, the interstudy precision and reliability were better with SPECT-35% than with SPECT-QBS. The sample sizes needed to objectify a change in right ventricular volumes or ejection fraction were lower with SPECT-35% than with SPECT-QBS. The interstudy precision and reliability of SPECT-35% and SPECT-QBS for the right ventricle were better than those of equilibrium planar radionuclide angiography, but poorer than those previously reported for the left ventricle with SPECT radionuclide angiography on the same population. SPECT-35% and SPECT-QBS present good interstudy precision and reliability for right ventricular function, with the results favouring the use of SPECT-35%. The results are better than those of equilibrium planar radionuclide angiography, but poorer than those previously reported for the left ventricle with SPECT radionuclide angiography. They need to be confirmed in a larger population.

Potential of right to left ventricular volume ratio measured on chest CT for the prediction of pulmonary hypertension: correlation with pulmonary arterial systolic pressure estimated by echocardiography

International Nuclear Information System (INIS)

Lee, Heon; Kim, Seok Yeon; Lee, Soo Jeong; Kim, Jae Kyun; Reddy, Ryan P.; Schoepf, U.J.

2012-01-01

To investigate the correlation of right ventricular (RV) to left ventricular (LV) volume ratio measured by chest CT with pulmonary arterial systolic pressure (PASP) estimated by echocardiography. 104 patients (72.47 ± 13.64 years; 39 male) who had undergone chest CT and echocardiography were divided into two groups (hypertensive and normotensive) based upon an echocardiography-derived PASP of 25 mmHg. RV to LV volume ratios (RV V /LV V ) were calculated. RV V /LV V was then correlated with PASP using regression analysis. The Area Under the Curve (AUC) for predicting pulmonary hypertension on chest CT was calculated. In the hypertensive group, the mean PASP was 46.29 ± 14.42 mmHg (29-98 mmHg) and there was strong correlation between the RV V /LV V and PASP (R = 0.82, p V /LV V were 0.990 and 0.892. RV V /LV V was 1.01 ± 0.44 (0.51-2.77) in the hypertensive and 0.72 ± 0.14 (0.52-1.11) in the normotensive group (P V /LV V , sensitivity and specificity for predicting pulmonary hypertension over 40 mmHg were 79.5 % and 90 %, respectively. The AUC for predicting pulmonary hypertension was 0.87 RV/LV volume ratios on chest CT correlate well with PASP estimated by echocardiography and can be used to predict pulmonary hypertension over 40 mmHg with high sensitivity and specificity. (orig.)

Automatic algorithm for monitoring systolic pressure variation and difference in pulse pressure.

Science.gov (United States)

Pestel, Gunther; Fukui, Kimiko; Hartwich, Volker; Schumacher, Peter M; Vogt, Andreas; Hiltebrand, Luzius B; Kurz, Andrea; Fujita, Yoshihisa; Inderbitzin, Daniel; Leibundgut, Daniel

2009-06-01

Difference in pulse pressure (dPP) reliably predicts fluid responsiveness in patients. We have developed a respiratory variation (RV) monitoring device (RV monitor), which continuously records both airway pressure and arterial blood pressure (ABP). We compared the RV monitor measurements with manual dPP measurements. ABP and airway pressure (PAW) from 24 patients were recorded. Data were fed to the RV monitor to calculate dPP and systolic pressure variation in two different ways: (a) considering both ABP and PAW (RV algorithm) and (b) ABP only (RV(slim) algorithm). Additionally, ABP and PAW were recorded intraoperatively in 10-min intervals for later calculation of dPP by manual assessment. Interobserver variability was determined. Manual dPP assessments were used for comparison with automated measurements. To estimate the importance of the PAW signal, RV(slim) measurements were compared with RV measurements. For the 24 patients, 174 measurements (6-10 per patient) were recorded. Six observers assessed dPP manually in the first 8 patients (10-min interval, 53 measurements); no interobserver variability occurred using a computer-assisted method. Bland-Altman analysis showed acceptable bias and limits of agreement of the 2 automated methods compared with the manual method (RV: -0.33% +/- 8.72% and RV(slim): -1.74% +/- 7.97%). The difference between RV measurements and RV(slim) measurements is small (bias -1.05%, limits of agreement 5.67%). Measurements of the automated device are comparable with measurements obtained by human observers, who use a computer-assisted method. The importance of the PAW signal is questionable.

Determination of left ventricular volume using gated blood pool tomography comparison with contrast ventriculography

International Nuclear Information System (INIS)

Lu Ping; Mo Lijun; Liu Xiujie

1992-01-01

48 patients with cardiac disease were studied with gated blood pool tomography to determine left ventricular volume at end diastole, end-systole and ejection fraction. The volumes were calculated from serial short-axis tomograms by multiplying the number of pixels and the known volume of each pixel. Excellent correlation was found between blood pool tomography and contrast ventriculographic volume. At end-diastole, r = 0.91 (P < 0.01); at end-systole, r = 0.95 (P < 0.01); for left ventricular ejection fraction, r 0.90 (P < 0.01). The results suggest that gated blood pool tomography is a promising noninvasive and direct method for measuring left ventricular volume

Long-term impact of systolic blood pressure and glycemia on the development of microalbuminuria in essential hypertension.

Science.gov (United States)

Pascual, Jose Maria; Rodilla, Enrique; Gonzalez, Carmen; Pérez-Hoyos, Santiago; Redon, Josep

2005-06-01

The objective was to assess the temporal impact of factors related to the development of microalbuminuria during the follow-up of young adult normoalbuminurics with high-normal blood pressure or at stage 1 of essential hypertension. Prospective follow-up was conducted on 245 normoalbuminuric hypertensive subjects (mean age 40.9 years; 134 men; blood pressure 139.7/88.6 mm Hg; body mass index 28.5 kg/m2) never treated previously with antihypertensive drugs, with yearly urinary albumin excretion measurements, until the development of microalbuminuria. After enrollment, patients were placed on usual care including nonpharmacological treatment or with an antihypertensive drug regime to achieve a blood pressure of 15 mg per 24-hour systolic blood pressure >139 mm Hg and a positive trend in fasting glucose were observed in the univariate analyses. However, in the multivariate analysis, only the baseline urinary albumin excretion and the trend of fasting glucose were independently related to the risk of developing microalbuminuria. In mild hypertensives, the development of microalbuminuria was linked to insufficient blood pressure control and to a progressive increment of glucose values.

Effects of positive end-expiratory pressure and recruitment maneuvers in a ventilator-induced injury mouse model.

Directory of Open Access Journals (Sweden)

Laura A Cagle

Full Text Available Positive-pressure mechanical ventilation is an essential therapeutic intervention, yet it causes the clinical syndrome known as ventilator-induced lung injury. Various lung protective mechanical ventilation strategies have attempted to reduce or prevent ventilator-induced lung injury but few modalities have proven effective. A model that isolates the contribution of mechanical ventilation on the development of acute lung injury is needed to better understand biologic mechanisms that lead to ventilator-induced lung injury.To evaluate the effects of positive end-expiratory pressure and recruitment maneuvers in reducing lung injury in a ventilator-induced lung injury murine model in short- and longer-term ventilation.5-12 week-old female BALB/c mice (n = 85 were anesthetized, placed on mechanical ventilation for either 2 hrs or 4 hrs with either low tidal volume (8 ml/kg or high tidal volume (15 ml/kg with or without positive end-expiratory pressure and recruitment maneuvers.Alteration of the alveolar-capillary barrier was noted at 2 hrs of high tidal volume ventilation. Standardized histology scores, influx of bronchoalveolar lavage albumin, proinflammatory cytokines, and absolute neutrophils were significantly higher in the high-tidal volume ventilation group at 4 hours of ventilation. Application of positive end-expiratory pressure resulted in significantly decreased standardized histology scores and bronchoalveolar absolute neutrophil counts at low- and high-tidal volume ventilation, respectively. Recruitment maneuvers were essential to maintain pulmonary compliance at both 2 and 4 hrs of ventilation.Signs of ventilator-induced lung injury are evident soon after high tidal volume ventilation (as early as 2 hours and lung injury worsens with longer-term ventilation (4 hrs. Application of positive end-expiratory pressure and recruitment maneuvers are protective against worsening VILI across all time points. Dynamic compliance can be used guide

Effects of positive end-expiratory pressure and recruitment maneuvers in a ventilator-induced injury mouse model

Science.gov (United States)

Franzi, Lisa M.; Linderholm, Angela L.; Last, Jerold A.; Adams, Jason Y.; Harper, Richart W.

2017-01-01

Background Positive-pressure mechanical ventilation is an essential therapeutic intervention, yet it causes the clinical syndrome known as ventilator-induced lung injury. Various lung protective mechanical ventilation strategies have attempted to reduce or prevent ventilator-induced lung injury but few modalities have proven effective. A model that isolates the contribution of mechanical ventilation on the development of acute lung injury is needed to better understand biologic mechanisms that lead to ventilator-induced lung injury. Objectives To evaluate the effects of positive end-expiratory pressure and recruitment maneuvers in reducing lung injury in a ventilator-induced lung injury murine model in short- and longer-term ventilation. Methods 5–12 week-old female BALB/c mice (n = 85) were anesthetized, placed on mechanical ventilation for either 2 hrs or 4 hrs with either low tidal volume (8 ml/kg) or high tidal volume (15 ml/kg) with or without positive end-expiratory pressure and recruitment maneuvers. Results Alteration of the alveolar-capillary barrier was noted at 2 hrs of high tidal volume ventilation. Standardized histology scores, influx of bronchoalveolar lavage albumin, proinflammatory cytokines, and absolute neutrophils were significantly higher in the high-tidal volume ventilation group at 4 hours of ventilation. Application of positive end-expiratory pressure resulted in significantly decreased standardized histology scores and bronchoalveolar absolute neutrophil counts at low- and high-tidal volume ventilation, respectively. Recruitment maneuvers were essential to maintain pulmonary compliance at both 2 and 4 hrs of ventilation. Conclusions Signs of ventilator-induced lung injury are evident soon after high tidal volume ventilation (as early as 2 hours) and lung injury worsens with longer-term ventilation (4 hrs). Application of positive end-expiratory pressure and recruitment maneuvers are protective against worsening VILI across all time points

Effects of positive end-expiratory pressure and recruitment maneuvers in a ventilator-induced injury mouse model.

Science.gov (United States)

Cagle, Laura A; Franzi, Lisa M; Linderholm, Angela L; Last, Jerold A; Adams, Jason Y; Harper, Richart W; Kenyon, Nicholas J

2017-01-01

Positive-pressure mechanical ventilation is an essential therapeutic intervention, yet it causes the clinical syndrome known as ventilator-induced lung injury. Various lung protective mechanical ventilation strategies have attempted to reduce or prevent ventilator-induced lung injury but few modalities have proven effective. A model that isolates the contribution of mechanical ventilation on the development of acute lung injury is needed to better understand biologic mechanisms that lead to ventilator-induced lung injury. To evaluate the effects of positive end-expiratory pressure and recruitment maneuvers in reducing lung injury in a ventilator-induced lung injury murine model in short- and longer-term ventilation. 5-12 week-old female BALB/c mice (n = 85) were anesthetized, placed on mechanical ventilation for either 2 hrs or 4 hrs with either low tidal volume (8 ml/kg) or high tidal volume (15 ml/kg) with or without positive end-expiratory pressure and recruitment maneuvers. Alteration of the alveolar-capillary barrier was noted at 2 hrs of high tidal volume ventilation. Standardized histology scores, influx of bronchoalveolar lavage albumin, proinflammatory cytokines, and absolute neutrophils were significantly higher in the high-tidal volume ventilation group at 4 hours of ventilation. Application of positive end-expiratory pressure resulted in significantly decreased standardized histology scores and bronchoalveolar absolute neutrophil counts at low- and high-tidal volume ventilation, respectively. Recruitment maneuvers were essential to maintain pulmonary compliance at both 2 and 4 hrs of ventilation. Signs of ventilator-induced lung injury are evident soon after high tidal volume ventilation (as early as 2 hours) and lung injury worsens with longer-term ventilation (4 hrs). Application of positive end-expiratory pressure and recruitment maneuvers are protective against worsening VILI across all time points. Dynamic compliance can be used guide the frequency

Direct measured systolic pressure gradients across the aorto-iliac segment in multiple-level-obstruction arteriosclerosis

DEFF Research Database (Denmark)

Noer, Ivan; Praestholm, J; Tønnesen, K H

1981-01-01

Patients with severe ischemia due to multi-level obstructions in the leg arteries both above and below the region were assessed preoperatively by intraarterial brachial and femoral artery pressure measurements. The systolic pressure drop along aorto-iliac obstructions was compared to the angiogra....... Due to large variations, however, the angiographic information was found to be useless in the individual patient. No difference in the pressure drop was found between cases in which rich and poor collateral networks were visualized....

Precision of gated equilibrium radioventriculography in measuring left ventricular stroke volume

International Nuclear Information System (INIS)

Bourguignon, M.H.; Wise, R.A.; Ehrlich, W.E.; Douglas, K.H.; Camargo, E.E.; Harrison, K.E.; Wagner, H.N. Jr.

1983-01-01

We have demonstrated that relative changes of small amplitude in ventricular stroke volume can be measured accurately in dogs when a fully automated technique for delineation of end diastolic and end systolic region of interest (ROI) is used. Consequently, we expect such a technique to be very sensitive in measuring relative changes of any ventricular quantitative parameter from gated equilibrium radio ventriculography in humans

Relation of N-Terminal Pro-B-Type Natriuretic Peptide and Left Ventricular Diastolic Function to Exercise Tolerance in Patients With Significant Valvular Heart Disease and Normal Left Ventricular Systolic Function.

Science.gov (United States)

Hwang, Ji-Won; Park, Sung-Ji; Cho, Eun Jeong; Kim, Eun Kyoung; Lee, Ga Yeon; Chang, Sung-A; Choi, Jin-Oh; Lee, Sang-Chol; Park, Seung Woo

2017-06-01

An association between N-terminal prohormone brain natriuretic peptide (NT-proBNP) and exercise tolerance in patients with valvular heart disease (VHD) has been suggested; however, there are few data available regarding this relation. The aim of this study is to evaluate the correlation between exercise tolerance and NT-proBNP in patients with asymptomatic or mildly symptomatic significant VHD and normal left ventricular ejection fraction (LV EF). A total of 96 patients with asymptomatic or mildly symptomatic VHD and normal LV EF (≥50%) underwent cardiopulmonary exercise echocardiography. NT-proBNP levels were determined at baseline and after exercise in 3 hours. Patients were divided in 2 groups based on lower (left atrial volume index before exercise, right ventricular systolic pressure before exercise, E velocity after exercise, and E/e' ratio after exercise varied significantly. In addition, peak VO 2 was inversely related to NT-proBNP before (r = -0.352, p left atrial volume index, E/e' ratio, and right ventricular systolic pressure before and after exercise. NT-proBNP after exercise was also directly related to the same parameters. NT-proBNP levels both before and after exercise were higher in the group with lower exercise tolerance. In conclusion, through the correlation among exercise tolerance, NT-proBNP, and parameters of diastolic dysfunction, we demonstrated that diastolic dysfunction and NT-proBNP could predict exercise tolerance in patients with significant VHD and normal LV EF. Copyright © 2017 Elsevier Inc. All rights reserved.

Prediction of acute cardiac rejection by changes in left ventricular volumes

International Nuclear Information System (INIS)

Novitzky, D.; Cooper, D.K.; Boniaszczuk, J.

1988-01-01

Sixteen patients underwent heart transplantation (11 orthotopic, five heterotopic). Monitoring for acute rejection was by both endomyocardial biopsy (EMB) and multigated equilibrium blood pool scanning with technetium 99m-labelled red blood cells. From the scans information was obtained on left ventricular volumes (stroke, end-diastolic, and end-systolic), ejection fraction, and heart rate. Studies (208) were made in the 16 patients. There was a highly significant correlation between the reduction in stroke volume and end-diastolic volume (and a less significant correlation in end-systolic volume) and increasing acute rejection seen on EMB. Heart rate and ejection fraction did not correlate with the development of acute rejection. Correlation of a combination of changes in stroke volume and end-diastolic volume with EMB showed a sensitivity of 85% and a specificity of 96%. Radionuclide scanning is therefore a useful noninvasive tool for monitoring acute rejection

Reliability of Doppler and stethoscope methods of determining systolic blood pressures: considerations for calculating an ankle-brachial index.

Science.gov (United States)

Chesbro, Steven B; Asongwed, Elmira T; Brown, Jamesha; John, Emmanuel B

2011-01-01

The purposes of this study were to: (1) identify the interrater and intrarater reliability of systolic blood pressures using a stethoscope and Doppler to determine an ankle-brachial index (ABI), and (2) to determine the correlation between the 2 methods. Peripheral arterial disease (PAD) affects approximately 8 to 12 million people in the United States, and nearly half of those with this disease are asymptomatic. Early detection and prompt treatment of PAD will improve health outcomes. It is important that clinicians perform tests that determine the presence of PAD. Two individual raters trained in ABI procedure measured the systolic blood pressures of 20 individuals' upper and lower extremities. Standard ABI measurement protocols were observed. Raters individually recorded the systolic blood pressures of each extremity using a stethoscope and a Doppler, for a total of 640 independent measures. Interrater reliability of Doppler measurements to determine SBP at the ankle was very strong (intraclass correlation coefficient [ICC], 0.93-0.99) compared to moderate to strong reliability using a stethoscope (ICC, 0.64-0.87). Agreement between the 2 devices to determine SBP was moderate to very weak (ICC, 0.13-0.61). Comparisons of the use of Doppler and stethoscope to determine ABI showed weak to very weak intrarater correlation (ICC, 0.17-0.35). Linear regression analysis of the 2 methods to determine ABI showed positive but weak to very weak correlations (r2 = .013, P = .184). A Doppler ultrasound is recommended over a stethoscope for accuracy in systolic pressure readings for ABI measurements.

Recruitment strategies and challenges in a large intervention trial: Systolic Blood Pressure Intervention Trial (SPRINT)

Science.gov (United States)

Ramsey, Thomas M; Snyder, Joni K; Lovato, Laura C; Roumie, Christianne L; Glasser, Steven P; Cosgrove, Nora M; Olney, Christine M; Tang, Rocky H; Johnson, Karen C; Still, Carolyn H; Gren, Lisa H; Childs, Jeffery C; Crago, Osa L; Summerson, John H; Walsh, Sandy M; Perdue, Letitia H; Bankowski, Denise M; Goff, David C

2016-01-01

Background The Systolic Blood Pressure Intervention Trial (SPRINT) is a multicenter, randomized clinical trial of 9,361 participants with hypertension who are ≥ 50 years old. The trial is designed to evaluate the effect of intensive systolic blood pressure control (systolic blood pressure goal recruitment strategies and lessons learned during recruitment of the SPRINT cohort and five targeted participant subgroups: pre-existing cardiovascular disease, pre-existing chronic kidney disease, age ≥ 75 years, women, and minorities. Methods In collaboration with the National Institutes of Health Project Office and SPRINT Coordinating Center, five Clinical Center Networks oversaw clinical site selection, recruitment, and trial activities. Recruitment began November 8, 2010 and ended March 15, 2013 (about 28 months). Various recruitment strategies were used, including mass mailing, brochures, referrals from healthcare providers or friends, posters, newspaper ads, radio ads, and electronic medical record searches. Results Recruitment was scheduled to last 24 months to enroll a target of 9,250 participants; in just over 28 months, the trial enrolled 9,361 participants. The trial screened 14,692 volunteers, with 33% of initial screens originating from the use of mass mailing lists. Screening results show that participants also responded to recruitment efforts through referral by SPRINT staff, healthcare providers, or friends (45%); brochures or posters placed in clinic waiting areas (15%); and television, radio, newspaper, internet ads, or toll-free numbers (8%). The overall recruitment yield (number randomized /number screened) was 64% (9,361 randomized /14,692 screened), 77% for those with cardiovascular disease, 79% for those with chronic kidney disease, 70% for those age ≥ 75 years, 55% for women, and 61% for minorities. As recruitment was observed to lag behind expectations, additional clinics were included and inclusion criteria were broadened, keeping event rates

Global Burden of Hypertension and Systolic Blood Pressure of at Least 110 to 115 mm Hg, 1990-2015

DEFF Research Database (Denmark)

Forouzanfar, Mohammad H; Liu, Patrick; Roth, Gregory A

2017-01-01

Importance: Elevated systolic blood (SBP) pressure is a leading global health risk. Quantifying the levels of SBP is important to guide prevention policies and interventions. Objective: To estimate the association between SBP of at least 110 to 115 mm Hg and SBP of 140 mm Hg or higher and the bur......Importance: Elevated systolic blood (SBP) pressure is a leading global health risk. Quantifying the levels of SBP is important to guide prevention policies and interventions. Objective: To estimate the association between SBP of at least 110 to 115 mm Hg and SBP of 140 mm Hg or higher...... and the burden of different causes of death and disability by age and sex for 195 countries and territories, 1990-2015. Design: A comparative risk assessment of health loss related to SBP. Estimated distribution of SBP was based on 844 studies from 154 countries (published 1980-2015) of 8.69 million participants...... in the primary analysis. Main Outcomes and Measures: Mean SBP level, cause-specific deaths, and health burden related to SBP (≥110-115 mm Hg and also ≥140 mm Hg) by age, sex, country, and year. Results: Between 1990-2015, the rate of SBP of at least 110 to 115 mm Hg increased from 73 119 (95% uncertainty...

Dose related anxiolytic effects of diazepam: relation with serum electrolytes, plasma osmolality and systolic blood pressure (sbp) in rats

International Nuclear Information System (INIS)

Farooq, R.; Haleem, D.J.; Haleem, M.A.

2008-01-01

Diazepam is an anxiolytic and anticonvulsant drug that also induces hypnosis. Changes in serum electrolyte balance, plasma osmolality and systolic blood pressure (SBP) are often associated with stress-induced anxiety. Administration of diazepam has been show to decrease stress-induced enhancement of hypothalamic pituitary adrenal cortical (HPA) axis. The present is designed to monitor the anxiolytic effects of different doses of diazepam (1 mg/kg, 2.5 mg/kg and 5 mg/kg) and its association with changes of serum electrolyte balance, plasma osmolality and SBP in rats. Administration of diazepam at doses of 1 mg/kg, 2.5 mg/kg and 5 mg/kg elicited anxiolytic effects monitored in light-dark transition test and increased serum concentration of electrolytes and plasma osmolality. Serum levels of magnesium as well as SBP decreased. The results are discussed in context of anxiolytic effects of diazepam to be mediated via a modulation of stress-induced increase in the activity of HPA-axis arid electrolytes balance. (author)

On-Treatment Blood Pressure and Cardiovascular Outcomes in Older Adults With Isolated Systolic Hypertension.

Science.gov (United States)

Yano, Yuichiro; Rakugi, Hiromi; Bakris, George L; Lloyd-Jones, Donald M; Oparil, Suzanne; Saruta, Takao; Shimada, Kazuyuki; Matsuoka, Hiroaki; Imai, Yutaka; Ogihara, Toshio

2017-02-01

Our aim was to assess optimal on-treatment blood pressure (BP) at which cardiovascular disease (CVD) and all-cause mortality risks are minimized in Japanese older adults with isolated systolic hypertension. We used data from the VALISH study (Valsartan in Elderly Isolated Systolic Hypertension) that recruited older adults (n=3035; mean age, 76 years) with systolic BP (SBP) of ≥160 mm Hg and diastolic BP of secondary outcome being all-cause mortality. Cox proportional hazards models were used to assess the CVD risk for each group. Over a median 3-year follow-up (8022 person-years), 93 CVD events and 52 deaths occurred. Using the on-treatment SBP of 130 to hypertension, SBP in the range between 130 and 144 mm Hg was associated with minimal adverse outcomes and a reduction in CVD and all-cause mortality. The BP range will need to be confirmed in randomized controlled trials. URL: https://www.clinicaltrials.gov. Unique identifier: NCT00151229. © 2017 American Heart Association, Inc.

Resistance training alone reduces systolic and diastolic blood pressure in prehypertensive and hypertensive individuals: meta-analysis.

Science.gov (United States)

de Sousa, Evitom Corrêa; Abrahin, Odilon; Ferreira, Ana Lorena Lima; Rodrigues, Rejane Pequeno; Alves, Erik Artur Cortinhas; Vieira, Rodolfo Paula

2017-11-01

The purpose of this study was to evaluate the effects of resistance training alone on the systolic and diastolic blood pressure in prehypertensive and hypertensive individuals. Our meta-analysis, followed the guidelines of PRISMA. The search for articles was realized by November 2016 using the following electronic databases: BIREME, PubMed, Cochrane Library, LILACS and SciELO and a search strategy that included the combination of titles of medical affairs and terms of free text to the key concepts: 'hypertension' 'hypertensive', 'prehypertensive', 'resistance training', 'strength training', and 'weight-lifting'. These terms were combined with a search strategy to identify randomized controlled trials (RCTs) and identified a total of 1608 articles: 644 articles BIREME, 53 SciELO, 722 PubMed, 122 Cochrane Library and 67 LILACS. Of these, five RCTs met the inclusion criteria and provided data on 201 individuals. The results showed significant reductions for systolic blood pressure (-8.2 mm Hg CI -10.9 to -5.5;I 2 : 22.5% P valor for heterogeneity=0.271 and effect size=-0.97) and diastolic blood pressure (-4.1 mm Hg CI -6.3 to -1.9; I 2 : 46.5% P valor for heterogeneity=0.113 and effect size=-0.60) when compared to group control. In conclusion, resistance training alone reduces systolic and diastolic blood pressure in prehypertensive and hypertensive subjects. The RCTs studies that investigated the effects of resistance training alone in prehypertensive and hypertensive patients support the recommendation of resistance training as a tool for management of systemic hypertension.

Left Atrial Systolic Force in Asymptomatic Aortic Stenosis

DEFF Research Database (Denmark)

Cioffi, Giovanni; Cramariuc, Dana; Dalsgaard, Morten

2011-01-01

LASF in the total study population was 21 ± 14 kdynes/cm(2) . The determinants of LASF were higher age, heart rate, body mass index, systolic blood pressure, left ventricular (LV) mass, mitral peak early velocity, maximal LA volume, and longer mitral deceleration time (multiple R(2) = 0.37, P ...Background: There is a limited knowledge about left atrial (LA) systolic force (LASF) and its key determinants in patients with asymptomatic mild-moderate aortic stenosis (AS). Methods: We used baseline clinic and echocardiographic data from 1,566 patients recruited in the simvastatin ezetimibe...... in aortic stenosis study evaluating the effect of placebo-controlled combined simvastatin and ezetimibe treatment in asymptomatic AS. The LASF was calculated by Manning's method. Low and high LASF were defined as 95th percentile of the distribution within the study population, respectively. Results: Mean...

Exercise testing and hemodynamic performance in healthy elderly persons

International Nuclear Information System (INIS)

Hitzhusen, J.C.; Hickler, R.B.; Alpert, J.S.; Doherty, P.W.

1984-01-01

To determine the effect of age on cardiovascular performance, 39 healthy elderly men and women, 70 to 83 years old, underwent treadmill thallium-201 exercise perfusion imaging and radionuclide equilibrium angiography at rest and during supine bicycle exercise. Five volunteers who had a positive exercise thallium test response were excluded from the study. Radionuclide left ventricular ejection fraction, regional wall abnormalities, relative cardiac output, stroke volume, end-diastolic volume and end-systolic volume were measured. Seventy-four percent of the subjects maintained or increased their ejection fraction with exercise. With peak exercise, mean end-diastolic volume did not change, end-systolic volume decreased and cardiac output and stroke volume increased. Moreover, in 35% of the subjects, minor regional wall motion abnormalities developed during exercise. There was no significant difference in the response of men and women with regard to these variables. However, more women than men had difficulty performing bicycle ergometry because they had never bicycled before. Subjects who walked daily performed the exercise tests with less anxiety and with a smaller increase in heart rate and systolic blood pressure

Effect of nasal continuous and biphasic positive airway pressure on lung volume in preterm infants

NARCIS (Netherlands)

Miedema, Martijn; van der Burg, Pauline S.; Beuger, Sabine; de Jongh, Frans H.; Frerichs, Inez; van Kaam, Anton H.

2013-01-01

To monitor regional changes in end-expiratory lung volume (EELV), tidal volumes, and their ventilation distribution during different levels of nasal continuous positive airway pressure (nCPAP) and nasal biphasic positive airway pressure (BiPAP) in stable preterm infants. By using electrical

Significance of white-coat hypertension in older persons with isolated systolic hypertension: a meta-analysis using the International Database on Ambulatory Blood Pressure Monitoring in Relation to Cardiovascular Outcomes population.

Science.gov (United States)

Franklin, Stanley S; Thijs, Lutgarde; Hansen, Tine W; Li, Yan; Boggia, José; Kikuya, Masahiro; Björklund-Bodegård, Kristina; Ohkubo, Takayoshi; Jeppesen, Jørgen; Torp-Pedersen, Christian; Dolan, Eamon; Kuznetsova, Tatiana; Stolarz-Skrzypek, Katarzyna; Tikhonoff, Valérie; Malyutina, Sofia; Casiglia, Edoardo; Nikitin, Yuri; Lind, Lars; Sandoya, Edgardo; Kawecka-Jaszcz, Kalina; Imai, Yutaka; Wang, Jiguang; Ibsen, Hans; O'Brien, Eoin; Staessen, Jan A

2012-03-01

The significance of white-coat hypertension in older persons with isolated systolic hypertension remains poorly understood. We analyzed subjects from the population-based 11-country International Database on Ambulatory Blood Pressure Monitoring in Relation to Cardiovascular Outcomes database who had daytime ambulatory blood pressure (BP; ABP) and conventional BP (CBP) measurements. After excluding persons with diastolic hypertension by CBP (≥90 mm Hg) or by daytime ABP (≥85 mm Hg), a history of cardiovascular disease, and persons <18 years of age, the present analysis totaled 7295 persons, of whom 1593 had isolated systolic hypertension. During a median follow-up of 10.6 years, there was a total of 655 fatal and nonfatal cardiovascular events. The analyses were stratified by treatment status. In untreated subjects, those with white-coat hypertension (CBP ≥140/<90 mm Hg and ABP <135/<85 mm Hg) and subjects with normal BP (CBP <140/<90 mm Hg and ABP <135/<85 mm Hg) were at similar risk (adjusted hazard rate: 1.17 [95% CI: 0.87-1.57]; P=0.29). Furthermore, in treated subjects with isolated systolic hypertension, the cardiovascular risk was similar in elevated conventional and normal daytime systolic BP as compared with those with normal conventional and normal daytime BPs (adjusted hazard rate: 1.10 [95% CI: 0.79-1.53]; P=0.57). However, both treated isolated systolic hypertension subjects with white-coat hypertension (adjusted hazard rate: 2.00; [95% CI: 1.43-2.79]; P<0.0001) and treated subjects with normal BP (adjusted hazard rate: 1.98 [95% CI: 1.49-2.62]; P<0.0001) were at higher risk as compared with untreated normotensive subjects. In conclusion, subjects with sustained hypertension who have their ABP normalized on antihypertensive therapy but with residual white-coat effect by CBP measurement have an entity that we have termed, "treated normalized hypertension." Therefore, one should be cautious in applying the term "white-coat hypertension" to persons

Mechanical ventilation with lower tidal volumes and positive end-expiratory pressure prevents pulmonary inflammation in patients without preexisting lung injury.

Science.gov (United States)

Wolthuis, Esther K; Choi, Goda; Dessing, Mark C; Bresser, Paul; Lutter, Rene; Dzoljic, Misa; van der Poll, Tom; Vroom, Margreeth B; Hollmann, Markus; Schultz, Marcus J

2008-01-01

Mechanical ventilation with high tidal volumes aggravates lung injury in patients with acute lung injury or acute respiratory distress syndrome. The authors sought to determine the effects of short-term mechanical ventilation on local inflammatory responses in patients without preexisting lung injury. Patients scheduled to undergo an elective surgical procedure (lasting > or = 5 h) were randomly assigned to mechanical ventilation with either higher tidal volumes of 12 ml/kg ideal body weight and no positive end-expiratory pressure (PEEP) or lower tidal volumes of 6 ml/kg and 10 cm H2O PEEP. After induction of anesthesia and 5 h thereafter, bronchoalveolar lavage fluid and/or blood was investigated for polymorphonuclear cell influx, changes in levels of inflammatory markers, and nucleosomes. Mechanical ventilation with lower tidal volumes and PEEP (n = 21) attenuated the increase of pulmonary levels of interleukin (IL)-8, myeloperoxidase, and elastase as seen with higher tidal volumes and no PEEP (n = 19). Only for myeloperoxidase, a difference was found between the two ventilation strategies after 5 h of mechanical ventilation (P volumes and PEEP may limit pulmonary inflammation in mechanically ventilated patients without preexisting lung injury. The specific contribution of both lower tidal volumes and PEEP on the protective effects of the lung should be further investigated.

Measuring systolic arterial blood pressure. Possible errors from extension tubes or disposable transducer domes.

Science.gov (United States)

Rothe, C F; Kim, K C

1980-11-01

The purpose of this study was to evaluate the magnitude of possible error in the measurement of systolic blood pressure if disposable, built-in diaphragm, transducer domes or long extension tubes between the patient and pressure transducer are used. Sinusoidal or arterial pressure patterns were generated with specially designed equipment. With a long extension tube or trapped air bubbles, the resonant frequency of the catheter system was reduced so that the arterial pulse was amplified as it acted on the transducer and, thus, gave an erroneously high systolic pressure measurement. The authors found this error to be as much as 20 mm Hg. Trapped air bubbles, not stopcocks or connections, per se, lead to poor fidelity. The utility of a continuous catheter flush system (Sorenson, Intraflow) to estimate the resonant frequency and degree of damping of a catheter-transducer system is described, as are possibly erroneous conclusions. Given a rough estimate of the resonant frequency of a catheter-transducer system and the magnitude of overshoot in response to a pulse, the authors present a table to predict the magnitude of probable error. These studies confirm the variability and unreliability of static calibration that may occur using some safety diaphragm domes and show that the system frequency response is decreased if air bubbles are trapped between the diaphragms. The authors conclude that regular procedures should be established to evaluate the accuracy of the pressure measuring systems in use, the transducer should be placed as close to the patient as possible, the air bubbles should be assiduously eliminated from the system.

A CROSS SECTIONAL STUDY TO FIND THE DIFFERENCE IN SYSTOLIC BLOOD PRESSURE BETWEEN ARMS AS A RISK MARKER FOR DIABETIC NEPHROPATHY IN PATIENTS WITH TYPE 2 DIABETES MELLITUS

OpenAIRE

Uday Subhash Bande; Anish Anthony Tekkinadath

2016-01-01

BACKGROUND Diabetic nephropathy is the commonest cause of end-stage renal disease in the developed world. Recent studies have demonstrated that a difference in systolic blood pressure between arms is associated with cardiovascular disease and microalbuminuria. It is considered a predictor for cardiovascular disease and a surrogate marker for early kidney damage among patients with both type 2 diabetes and hypertension. AIMS AND OBJECTIVES The aim was to investigate an associ...

The effect of positive end-expiratory pressure on pulse pressure ...

African Journals Online (AJOL)

The effect of positive end-expiratory pressure on pulse pressure variation. FJ Smith, M Geyser, I Schreuder, PJ Becker. Abstract. Objectives: To determine the effect of different levels of positive end-expiratory pressure (PEEP) on pulse pressure variation (PPV). Design: An observational study. Setting: Operating theatres of a ...

Human gallbladder pressure and volume

DEFF Research Database (Denmark)

Borly, L; Højgaard, L; Grønvall, S

1996-01-01

volume with only slight changes in intraluminal pressure (n = 4). Except for the zero drift, this piece of equipment seemed to fulfil the requirements of being able to measure pressure in the GB. In vivo measurements showed a good clinical reproducibility of the method, and also that respiration...... influenced by respiration (n = 8) and the pressure seems to be higher in the sitting position than in the supine position (n = 5). Cystic duct opening pressure was 10.4, 11.2 and 16.8 mmHg (n = 3). Pressure-volume responses showed that the GB up to a certain volume could accommodate increases in intraluminal...... and patient posture influenced the pressure measurements. Further, a GB pressure-volume relationship was demonstrated, and the possibility of a cystic duct opening pressure was described....

Comparison of noninvasive assessments of central blood pressure using general transfer function and late systolic shoulder of the radial pressure wave.

Science.gov (United States)

Wohlfahrt, Peter; Krajcoviechová, Alena; Seidlerová, Jitka; Mayer, Otto; Filipovsky, Jan; Cífková, Renata

2014-02-01

Central systolic blood pressure (cSBP) can be derived by the general transfer function of the radial pressure wave, as used in the SphygmoCor device, or by regression equation from directly measured late systolic shoulder of the radial pressure wave (pSBP2), as used in the Omron HEM-9000AI device. The aim of this study was to compare the SphygmoCor estimates of cSBP with 2 estimates of cSBP provided by the Omron HEM-9000AI (cSBP, pSBP2) in a large cohort of the white population. In 391 patients aged 52.3±13.5 years (46% men) from the Czech post-MONICA Study, cSBP was measured using the SphygmoCor and Omron HEM-9000AI devices in random order. Omron cSBP and pSBP2 were perfectly correlated (r = 1.0; P wave provides a comparable accuracy with the validated general transfer function. When comparing Omron HEM-9000AI and SphygmoCor estimates of cSBP, Omron pSBP2 should be used. The difference between both devices in cSBP may be explained by differences in calibration.

Effect of fluid loading on left ventricular volume and stroke volume variability in patients with end-stage renal disease: a pilot study

Science.gov (United States)

Kanda, Hirotsugu; Hirasaki, Yuji; Iida, Takafumi; Kanao-Kanda, Megumi; Toyama, Yuki; Kunisawa, Takayuki; Iwasaki, Hiroshi

2015-01-01

Purpose The aim of this study was to investigate fluid loading-induced changes in left ventricular end-diastolic volume (LVEDV) and stroke volume variability (SVV) in patients with end-stage renal disease (ESRD) using real-time three-dimensional transesophageal echocardiography and the Vigileo-FloTrac system. Patients and methods After obtaining ethics committee approval and informed consent, 28 patients undergoing peripheral vascular procedures were studied. Fourteen patients with ESRD on hemodialysis (HD) were assigned to the HD group and 14 patients without ESRD were assigned to the control group. Institutional standardized general anesthesia was provided in both groups. SVV was measured using the Vigileo-FloTrac system. Simultaneously, a full-volume three-dimensional transesophageal echocardiography dataset was acquired to measure LVEDV, left ventricular end-systolic volume, and left ventricular ejection fraction. Measurements were obtained before and after loading 500 mL hydroxyethyl starch over 30 minutes in both groups. Results In the control group, intravenous colloid infusion was associated with a significant decrease in SVV (13.8%±2.6% to 6.5%±2.6%, P<0.001) and a significant increase in LVEDV (83.6±23.4 mL to 96.1±28.8 mL, P<0.001). While SVV significantly decreased after infusion in the HD group (16.2%±6.0% to 6.2%±2.8%, P<0.001), there was no significant change in LVEDV. Conclusion Our preliminary data suggest that fluid responsiveness can be assessed not by LVEDV but also by SVV due to underlying cardiovascular pathophysiology in patients with ESRD. PMID:26527879

Evaluation of right ventricular function using gated equilibrium blood pool radionuclide ventriculography in patients with congenital volume and pressure overload late after surgical repair

International Nuclear Information System (INIS)

Hirata, Nobuaki; Sakakibara, Tetsuo; Watanabe, Shinichiro; Nomura, Fumikazu; Akamatsu, Hiroki; Matsumura, Yasushi; Yamamoto, Kazuhiro; Sasaki, Jiro; Kodama, Kazuhisa

1991-01-01

The effects of congenital right ventricular pressure and volume overload were studied in 3 patients with pulmonary stenosis, 7 with atrial septal defect and 6 with atrial septal defect plus pulmonary stenosis late after successful surgical correction. Gated equilibrium blood pool radionuclide ventriculography was used to measure right ventricular function at rest and during exercise and to compare it with eight normal subjects. Right ventricular ejection fractions at rest and during exercise were measured to be 61±9% and 66±13%, respectively, in the group with pulmonary stenosis, 49±7% and 54±8% in the group with atrial septal defect, and 65±13% and 69±13% in the group with atrial septal defect plus pulmonary stenosis. The values in the groups with pulmonary stenosis and atrial septal defect plus pulmonary stenosis were significantly higher than the control subjects (45±5% and 51±5%, p<0.01). The peak filling rate at rest and during exercise was also significantly higher in the groups with pulmonary stenosis and atrial septal defect plus pulmonary stenosis than in controls (at rest, 2.72±0.72, 2.53±0.94 vs. 1.64±0.24 p<0.05; during exercise, 4.38±1.23, 4.13±1.18 vs. 2.25±0.62, p<0.01). When patients with right ventricular systolic pressure equal to or greater than left ventricular systolic pressure and those with right ventricular systolic pressure less than left ventricular systolic pressure were compared, the right ventricular ejection fraction and peak filling rate were greater with the higher pressure at rest (71±10% and 3.12±0.81% vs. 55±3% and 2.30±0.27, p<0.05) and during exercise (75±11% and 4.86±1.01 vs. 59±3% and 2.61±0.35, p<0.05). Postoperative right ventricular hyperfunction may be due to preoperative pressure, but not volume, overload. (author)

Potential of right to left ventricular volume ratio measured on chest CT for the prediction of pulmonary hypertension: correlation with pulmonary arterial systolic pressure estimated by echocardiography

Energy Technology Data Exchange (ETDEWEB)

Lee, Heon [Soon Chun Hyang University, Department of Radiology, Bucheon (Korea, Republic of); Kim, Seok Yeon [Seoul Medical Center, Department of Cardiology, Seoul (Korea, Republic of); Lee, Soo Jeong [Terarecon Korea, Seoul (Korea, Republic of); Kim, Jae Kyun [Chung-Ang University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Reddy, Ryan P.; Schoepf, U.J. [Medical University of South Carolina, Department of Radiology and Radiological Science and Division of Cardiology, Department of Medicine, Charleston, SC (United States)

2012-09-15

To investigate the correlation of right ventricular (RV) to left ventricular (LV) volume ratio measured by chest CT with pulmonary arterial systolic pressure (PASP) estimated by echocardiography. 104 patients (72.47 {+-} 13.64 years; 39 male) who had undergone chest CT and echocardiography were divided into two groups (hypertensive and normotensive) based upon an echocardiography-derived PASP of 25 mmHg. RV to LV volume ratios (RV{sub V}/LV{sub V}) were calculated. RV{sub V}/LV{sub V} was then correlated with PASP using regression analysis. The Area Under the Curve (AUC) for predicting pulmonary hypertension on chest CT was calculated. In the hypertensive group, the mean PASP was 46.29 {+-} 14.42 mmHg (29-98 mmHg) and there was strong correlation between the RV{sub V}/LV{sub V} and PASP (R = 0.82, p < 0.001). The intraobserver and interobserver correlation coefficients for RV{sub V}/LV{sub V} were 0.990 and 0.892. RV{sub V}/LV{sub V} was 1.01 {+-} 0.44 (0.51-2.77) in the hypertensive and 0.72 {+-} 0.14 (0.52-1.11) in the normotensive group (P <0.05). With 0.9 as the cutoff for RV{sub V}/LV{sub V}, sensitivity and specificity for predicting pulmonary hypertension over 40 mmHg were 79.5 % and 90 %, respectively. The AUC for predicting pulmonary hypertension was 0.87 RV/LV volume ratios on chest CT correlate well with PASP estimated by echocardiography and can be used to predict pulmonary hypertension over 40 mmHg with high sensitivity and specificity. (orig.)

Pacing stress echocardiography

Directory of Open Access Journals (Sweden)

Agrusta Marco

2005-12-01

Full Text Available Abstract Background High-rate pacing is a valid stress test to be used in conjunction with echocardiography; it is independent of physical exercise and does not require drug administration. There are two main applications of pacing stress in the echo lab: the noninvasive detection of coronary artery disease through induction of a regional transient dysfunction; and the assessment of contractile reserve through peak systolic pressure/ end-systolic volume relationship at increasing heart rates to assess global left ventricular contractility. Methods The pathophysiologic rationale of pacing stress for noninvasive detection of coronary artery disease is obvious, with the stress determined by a controlled increase in heart rate, which is a major determinant of myocardial oxygen demand, and thereby tachycardia may exceed a fixed coronary flow reserve in the presence of hemodynamically significant coronary artery disease. The use of pacing stress echo to assess left ventricular contractile reserve is less established, but promising. Positive inotropic interventions are mirrored by smaller end-systolic volumes and higher end-systolic pressures. An increased heart rate progressively increases the force of ventricular contraction (Bowditch treppe or staircase phenomenon. To build the force-frequency relationship, the force is determined at different heart rate steps as the ratio of the systolic pressure (cuff sphygmomanometer/end-systolic volume index (biplane Simpson rule. The heart rate is determined from ECG. Conclusion Two-dimensional echocardiography during pacing is a useful tool in the detection of coronary artery disease. Because of its safety and ease of repeatability noninvasive pacing stress echo can be the first-line stress test in patients with permanent pacemaker. The force-frequency can be defined as up- sloping (normal when the peak stress pacing systolic pressure/end-systolic volume index is higher than baseline and intermediate stress

Reciprocal Interaction of 24-Hour Blood Pressure Variability and Systolic Blood Pressure on Outcome in Stroke Thrombolysis.

Science.gov (United States)

Kellert, Lars; Hametner, Christian; Ahmed, Niaz; Rauch, Geraldine; MacLeod, Mary J; Perini, Francesco; Lees, Kennedy R; Ringleb, Peter A

2017-07-01

Significance and management of blood pressure (BP) changes in acute stroke care are unclear. Here, we aimed to investigate the impact of 24-hour BP variability (BPV) on outcome in patients with acute ischemic stroke treated with intravenous thrombolysis. From the Safe Implementation of Treatment in Stroke International Stroke Thrombolysis registry, 28 976 patients with documented pre-treatment systolic BP at 2 and 24 hours were analyzed. The primary measure of BP variability was successive variability. Data were preprocessed using coarsened exact matching. We assessed early neurological improvement, symptomatic intracerebral hemorrhage (SICH), and long-term functional outcome (modified Rankin Scale [mRS] at 90 days) by binary and ordinal regression analyses. Attempts to explain successive variation for analysis of BPV with patients characteristics at admission found systolic BP (5.5% variance) to be most influential, yet 92% of BPV variance remained unexplained. Independently from systolic BP, successive variation for analysis of BPV was associated with poor functional outcome mRS score of 0 to 2 (odds ratio [OR], 0.94; 95% confidence interval [CI], 0.90-0.98), disadvantage across the shift of mRS (OR, 1.04; 95% CI, 1.01-1.08), mortality (OR, 1.10; 95% CI, 1.01-1.08), SICH SITS (OR, 1.14; 95% CI, 1.06-1.23), and SICH ECASS (OR, 1.24; 95% CI, 1.10-1.40; ECASS [European Cooperative Acute Stroke Study 2]). Analyzing successive variation for analysis of BPV as a function of pre-treatment, systolic BP significantly improved the prediction of functional outcome (mRS score of 0-1, mRS score of 0-2, neurological improvement, mRS-shift: all P interaction accounting for pre-treatment BP and the acute BP course (ie, BPV) to achieve best possible outcome for the patient. © 2017 American Heart Association, Inc.

First-order approximation for the pressure-flow relationship of spontaneously contracting lymphangions.

Science.gov (United States)

Quick, Christopher M; Venugopal, Arun M; Dongaonkar, Ranjeet M; Laine, Glen A; Stewart, Randolph H

2008-05-01

To return lymph to the great veins of the neck, it must be actively pumped against a pressure gradient. Mean lymph flow in a portion of a lymphatic network has been characterized by an empirical relationship (P(in) - P(out) = -P(p) + R(L)Q(L)), where P(in) - P(out) is the axial pressure gradient and Q(L) is mean lymph flow. R(L) and P(p) are empirical parameters characterizing the effective lymphatic resistance and pump pressure, respectively. The relation of these global empirical parameters to the properties of lymphangions, the segments of a lymphatic vessel bounded by valves, has been problematic. Lymphangions have a structure like blood vessels but cyclically contract like cardiac ventricles; they are characterized by a contraction frequency (f) and the slopes of the end-diastolic pressure-volume relationship [minimum value of resulting elastance (E(min))] and end-systolic pressure-volume relationship [maximum value of resulting elastance (E(max))]. Poiseuille's law provides a first-order approximation relating the pressure-flow relationship to the fundamental properties of a blood vessel. No analogous formula exists for a pumping lymphangion. We therefore derived an algebraic formula predicting lymphangion flow from fundamental physical principles and known lymphangion properties. Quantitative analysis revealed that lymph inertia and resistance to lymph flow are negligible and that lymphangions act like a series of interconnected ventricles. For a single lymphangion, P(p) = P(in) (E(max) - E(min))/E(min) and R(L) = E(max)/f. The formula was tested against a validated, realistic mathematical model of a lymphangion and found to be accurate. Predicted flows were within the range of flows measured in vitro. The present work therefore provides a general solution that makes it possible to relate fundamental lymphangion properties to lymphatic system function.

Loading-unloading pressure-volume curves for rocks

International Nuclear Information System (INIS)

Stephens, D.R.; Lilley, E.M.

1970-01-01

The stress-strain codes (SOC and TENSOR) used to calculate phenomenology of nuclear explosion for the Plowshare Program require inter alia the pressure-volume relationships of the earth media. In this paper we describe a rapid and accurate method to obtain pressure-volume data to 40 kb at 25 deg. C for rocks. These experimental results may also be related to the in situ elastic properties of the rock and to other laboratory measurement of properties, such as ultrasonic experiments with pressure and Hugoniot determinations. Qualitative features of the pressure-volume curves can be related to the initial porosity of the rock. A porous rock is usually quite compressible at low pressures. If the porosity is in the form of narrow cracks, the cracks are closed at a pressure of about 3 to 6 kb, after which the rock is much less compressible. If the porosity is in the form of spherical pores, it is not necessarily removed even at pressures of 40 kb, depending on the strength of the rock, and the compressibility is higher at all pressures than for a similar rock containing no porosity. Data for water-saturated samples show the phase transformation due to free water at about 10 and 22 kb. However, the presence of 'nonliquid' water, which is loosely contained within the lattice of clay or zeolitic minerals or adsorbed on particle surfaces, is also observed. (author)

Loading-unloading pressure-volume curves for rocks

Energy Technology Data Exchange (ETDEWEB)

Stephens, D R; Lilley, E M [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1970-05-01

The stress-strain codes (SOC and TENSOR) used to calculate phenomenology of nuclear explosion for the Plowshare Program require inter alia the pressure-volume relationships of the earth media. In this paper we describe a rapid and accurate method to obtain pressure-volume data to 40 kb at 25 deg. C for rocks. These experimental results may also be related to the in situ elastic properties of the rock and to other laboratory measurement of properties, such as ultrasonic experiments with pressure and Hugoniot determinations. Qualitative features of the pressure-volume curves can be related to the initial porosity of the rock. A porous rock is usually quite compressible at low pressures. If the porosity is in the form of narrow cracks, the cracks are closed at a pressure of about 3 to 6 kb, after which the rock is much less compressible. If the porosity is in the form of spherical pores, it is not necessarily removed even at pressures of 40 kb, depending on the strength of the rock, and the compressibility is higher at all pressures than for a similar rock containing no porosity. Data for water-saturated samples show the phase transformation due to free water at about 10 and 22 kb. However, the presence of 'nonliquid' water, which is loosely contained within the lattice of clay or zeolitic minerals or adsorbed on particle surfaces, is also observed. (author)

Left ventricular ejection fraction and volumes as measured by 3D echocardiography and ultrafast computed tomography

International Nuclear Information System (INIS)

Vieira, Marcelo Luiz Campos; Nomura, Cesar H.; Tranchesi Junior, Bernardino; Oliveira, Wercules A. de; Naccarato, Gustavo; Serpa, Bruna S.; Passos, Rodrigo B.D.; Funari, Marcelo B. G.; Fischer, Claudio H.; Morhy, Samira S.

2009-01-01

Background: Real-time three-dimensional echocardiography (RT-3D-Echo) and ultrafast computed tomography (CT) are two novel methods for the analysis of LV ejection fraction and volumes. Objective: To compare LVEF and volume measurements as obtained using RT-3D-Echo and ultrafast CT. Methods: Thirty nine consecutive patients (27 men, mean age of 57+- 12 years) were studied using RT-3D-Echo and 64-slice ultrafast CT. LVEF and LV volumes were analyzed. Statistical analysis: coefficient of correlation (r: Pearson), Bland-Altman analysis, linear regression analysis, 95% CI, p 5 .58)%; end-diastolic volume ranged from 49.6 to 178.2 (87+-27.8) ml; end-systolic volume ranged from 11.4 to 78 (33.1+-13.6) ml. CT scan measurements: LVEF ranged from 53 to 86% (67.8+-7.78); end-diastolic volume ranged from 51 to 186 (106.5+-30.3) ml; end-systolic volume ranged from 7 to 72 (35.5+-13.4)ml. Correlations between RT-3D-Echo and CT were: LVEF (r: 0.7888, p<0.0001, 95% CI 0.6301 to 0.8843); end-diastolic volume (r: 0.7695, p<0.0001, 95% CI 0.5995 to 0.8730); end-systolic volume (r: 0.8119, p<0.0001, 95% CI 0.6673 to 0.8975). Conclusion: Good correlation between LVEF and ventricular volume parameters as measured by RT-3D-Echo and 64-slice ultrafast CT was found in the present case series. (author)

Echocardiographic assessment of systolic pulmonary arterial pressure in HIV-positive patients.

Directory of Open Access Journals (Sweden)

Mehrnaz Rasoulinejad

2014-11-01

Full Text Available Pulmonary hypertension is rare but is one of the complications that occur due to HIV infection. Symptoms of HIV-associated pulmonary arterial hypertension are often non-specific but the main symptom of the disease is dyspnea. In this cross-sectional study, we measured systolic pulmonary arterial pressure (SPAP by echocardiographic methods among HIV-positive patients who received ART. This research is a descriptive, cross-sectional study of 170 HIV-positive patients that was conducted in Imam-Khomeini hospital, Tehran, Iran during 2011-2013. All patients regularly received antiretroviral therapy at least for recent 2 years. There were not any cardiopulmonary symptoms (cough, dyspnea, exertional fatigue and chest discomfort in these patients. All participants underwent echocardiography to estimate SPAP. The participants comprised 108 males (63.5% and 62 females (46.5%. The mean age of patients was 41 years old, and the mean duration of HIV infection was 5.5 years. The mean CD4 cell count was 401 cell/µl. The principal regimen of antiretroviral therapy included two nucleoside reverse transcriptase inhibitor (NRTI and one non-nucleoside reverse transcriptase inhibitor (NNRTI in the hospital. The mean of systolic pulmonary arterial pressure was 25 mmHg in the participants; 156 (93.4% of them had SPAP ≤ 30 mmHg (normal, six (3.6% had SPAP: 31-35 mmHg (borderline and five (3% had SPAP > 35 mmHg (pulmonary hypertension. Our results indicated a significant increase of pulmonary hypertension in asymptomatic HIV-positive patients that had no association with any other risk factor. Also, antiretroviral therapy was not a risk factor for pulmonary hypertension in this study.

Evaluation of left ventricular volumes in patients with congenital heart disease and abnormal left ventricular geometry. Comparison of MRI and transthoracic 3-dimensional echocardiography

International Nuclear Information System (INIS)

Gutberlet, M.; Grothoff, M.; Roettgen, R.; Lange, P.; Felix, R.; Abdul-Khaliq, H.; Schroeter, J.; Schmitt, B.; Vogel, M.

2003-01-01

Purpose: To assess the new method of 3-dimensional echocardiography in comparison to the 'gold standard' MRI as to its ability to calculate left ventricular volumes in patients with congenital heart disease. Materials and methods: Eighteen patients between the ages of 3.9 to 37.3 years (mean: 12.8±9.7) with a geometrically abnormal left ventricle were examined using a 1.5 T scanner with a fast gradient-echo sequence (TR=14 ms, TE=2.6-2.9 ms, FOV=300-400 mm, flip angle=20 , matrix=128:256, slice thickness=5 mm, retrospective gating) in multislice-multiphase technique. Transthoracic 3D-echocardiography was performed with a 3.5 MHz transducer and a Tomtec trademark (Munich, Germany) system for 3D reconstruction. Results: Volume calculation was possible in all patients with 3D-echocardiography, but the muscle mass calculation only succeeded in 11 to 18 patients (61%) due to inadequate visualization of the entire myocardium. Comparing MRI and 3D-echocardiography, the correlation was r=0.97 for the end-systolic volumes, r=0.98 for the end-diastolic volumes, r=0.79 for the end-systolic muscle mass and r=0.77 for the end-diastolic muscle mass. The agreement between both methods was considered good for the calculated end-diastolic volumes and sufficient for the calculated end-systolic volumes. The muscle mass calculations showed larger differences especially for the end-systolic mass. Mean intraobserver variability was 18.6% for end-systolic and 8.3% for end-diastolic volumes. Conclusion: In patients with an abnormal left ventricular configuration due to congenital heart disease, the new method of 3D-echocardiography is sufficient for volume calculations in preselected patients. The high intraobserver variability is still a limitation of transthoracic 3D-echocardiography in comparison to MRI. (orig.) [de

Interarm systolic blood pressure difference is associated with myocardial injury after noncardiac surgery.

Science.gov (United States)

Belen, Erdal; Ozal, Ender; Bayyigit, Akif; Gunaydın, Senay; Helvacı, Aysen

Myocardial injury after non-cardiac surgery (MINS) is closely related to increased cardiovascular mortality. To evaluate the relationship between MINS and interarm systolic blood pressure difference (IASBPD), which has previously been shown to correlate with the frequency of cardiovascular events and arterial arteriosclerotic processes. This observational, single-centre cohort study included 240 consecutive noncardiac surgery patients aged ≥ 45 years. Simultaneous blood pressure recordings were taken preoperatively and IASBPD was calculated. Patients' electrocardiography recordings and high sensitivity cardiac troponin T (hscTnT) levels were obtained for a period of three days postoperatively. Postoperatively, 27 (11.3%) patients were found to have MINS when hscTnT ≥ 14 ng/L was taken as a cut-off value. IASBPD > 10 mm Hg was found in 44 (18.3%) patients. When IASBPD was accepted to be a continuous variable, there was a higher IASBPD value in the MINS group (9.4 ± 5.0 vs. 4.5 ± 3.8, p 10 mm Hg and those not, exaggerate IASBPD was found to be more frequent in patients developing MINS (16 [59.3%] vs. 28 [13.1%], respectively, p 10 mm Hg to be independently associated with the development of MINS (OR: 30.82; CI: 9.14-103.98; p AUC = 0.79; 95% CI 0.71-0.87). Increased IASBPD is closely related to development of MINS. The preoperative measurement of blood pressure from both arms may be an important and easy to use clinical tool in determining cardiovascular risk.

Ischemic preconditioning of the lower extremity attenuates the normal hypoxic increase in pulmonary artery systolic pressure.

Science.gov (United States)

Foster, Gary P; Westerdahl, Daniel E; Foster, Laura A; Hsu, Jeffrey V; Anholm, James D

2011-12-15

Ischemic pre-condition of an extremity (IPC) induces effects on local and remote tissues that are protective against ischemic injury. To test the effects of IPC on the normal hypoxic increase in pulmonary pressures and exercise performance, 8 amateur cyclists were evaluated under normoxia and hypoxia (13% F(I)O(2)) in a randomized cross-over trial. IPC was induced using an arterial occlusive cuff to one thigh for 5 min followed by deflation for 5 min for 4 cycles. In the control condition, the resting pulmonary artery systolic pressure (PASP) increased from a normoxic value of 25.6±2.3 mmHg to 41.8±7.2 mmHg following 90 min of hypoxia. In the IPC condition, the PASP increased to only 32.4±3.1 mmHg following hypoxia, representing a 72.8% attenuation (p=0.003). No significant difference was detected in cycle ergometer time trial duration between control and IPC conditions with either normoxia or hypoxia. IPC administered prior to hypoxic exposure was associated with profound attenuation of the normal hypoxic increase of pulmonary artery systolic pressure. Published by Elsevier B.V.

MANAGING HIGH-END, HIGH-VOLUME INNOVATIVE PRODUCTS

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Gembong Baskoro

2008-01-01

Full Text Available This paper discuses the concept of managing high-end, high-volume innovative products. High-end, high-volume consumer products are products that have considerable influence to the way of life. Characteristic of High-end, high-volume consumer products are (1 short cycle time, (2 quick obsolete time, and (3 rapid price erosion. Beside the disadvantages that they are high risk for manufacturers, if manufacturers are able to understand precisely the consumer needs then they have the potential benefit or success to be the market leader. High innovation implies to high utilization of the user, therefore these products can influence indirectly to the way of people life. The objective of managing them is to achieve sustainability of the products development and innovation. This paper observes the behavior of these products in companies operated in high-end, high-volume consumer product.

FCT (functional computed tomography) evaluation of the lung volumes at different PEEP (positive-end expiratory pressure) ventilation pattern, in mechanical ventilated patients

International Nuclear Information System (INIS)

Papi, M.G.; Di Segni, R.; Mazzetti, G.; Staffa, F.; Conforto, F.; Calimici, R.; Salvi, A.; Matteucci, G.

2007-01-01

Purpose To evaluate with FCT (functional computed tomography) total lung volume and fractional lung volumes at different PEEP (positive end expiratory pressure) values in acute mechanically ventilated patients. Methods Nine ICU (intensive care unity) patients (1 lung pneumonia, 2 polytrauma, 2 sepsis, 3 brain surgery, 1 pulmonary embolism); mean age 48 ± 15 years, 6 male, 3 female; GE 16 MDCT scan was performed with acquisition from apex to diaphragma in seven seca at different PEEP values. Raw CT data were analysed by an advantage workstation to obtain volume density masks and histograms of both lungs and each lung and these density ranges were applied: - 1000 - 950 hyper-ventilated lung, -900 - 650 well aerated lung, -950 - 500 all aerated lung, -500 + 200 lung tissue. Total and fractional lung volumes, Hounsfield unit (HU) were calculated and compared at different PEEP values (0, 5, 10, 15 cm H 2 O). In four patients lung volumes were compared between the more and the less involved lung at increased PEEP. Statistic analysis: comparison means-medians tests. Results Data calculated at five PEEP showed unexpected decrease of total lung volume and increase of lung density (HU); proportionally no significant improvement of oxigenation. (orig.)

FCT (functional computed tomography) evaluation of the lung volumes at different PEEP (positive-end expiratory pressure) ventilation pattern, in mechanical ventilated patients

Energy Technology Data Exchange (ETDEWEB)

Papi, M.G.; Di Segni, R.; Mazzetti, G.; Staffa, F. [Dept. of Radiology, S. Giovanni HS, Rome (Italy); Conforto, F.; Calimici, R.; Salvi, A. [Dept. of Anesthesiology, S. Giovanni HS, Rome (Italy); Matteucci, G. [Dept. of Pneumology, S. Giovanni HS, Rome (Italy)

2007-06-15

Purpose To evaluate with FCT (functional computed tomography) total lung volume and fractional lung volumes at different PEEP (positive end expiratory pressure) values in acute mechanically ventilated patients. Methods Nine ICU (intensive care unity) patients (1 lung pneumonia, 2 polytrauma, 2 sepsis, 3 brain surgery, 1 pulmonary embolism); mean age 48 {+-} 15 years, 6 male, 3 female; GE 16 MDCT scan was performed with acquisition from apex to diaphragma in seven seca at different PEEP values. Raw CT data were analysed by an advantage workstation to obtain volume density masks and histograms of both lungs and each lung and these density ranges were applied: - 1000 - 950 = hyper-ventilated lung, -900 - 650 well aerated lung, -950 - 500 all aerated lung, -500 + 200 lung tissue. Total and fractional lung volumes, Hounsfield unit (HU) were calculated and compared at different PEEP values (0, 5, 10, 15 cm H{sub 2}O). In four patients lung volumes were compared between the more and the less involved lung at increased PEEP. Statistic analysis: comparison means-medians tests. Results Data calculated at five PEEP showed unexpected decrease of total lung volume and increase of lung density (HU); proportionally no significant improvement of oxigenation. (orig.)

Effects of curative treatment emphasizing endurance training on the performance and blood pressure of hypertensive and normotensives

Science.gov (United States)

Worms, F.

1981-01-01

The problem of normal values of blood pressure after exercise taking into account the blood pressure at the end of the exercise test is discussed. Hypertensives showed a lower working capacity than normotensives. In normotensives, however, systolic blood pressure at the end of an exercise correlated well with the working capacity. After the endurance cure submaximal blood pressure was markedly lower in hypertensives with a striking dependence on the level of initial values. Systolic blood pressure at the end of an exercise test was not changed significantly. Most probably it is not possible to overcome this malregulation in hypertensives by endurance training alone.

Lung-protective ventilation in intensive care unit and operation room : Tidal volume size, level of positive end-expiratory pressure and driving pressure

NARCIS (Netherlands)

Serpa Neto, A.

2017-01-01

Several investigations have shown independent associations between three ventilator settings – tidal volume size, positive end–expiratory pressure (PEEP) and driving pressure – and outcomes in patients with the acute respiratory distress syndrome (ARDS). There is an increasing notion that similar

Skin perfusion pressure measured by isotope washout in legs with arterial occlusive disease. Evaluation of different tracers, comparison to segmental systolic pressure, angiography and transcutaneous oxygen tension and variations during changes in systemic blood pressure

DEFF Research Database (Denmark)

Holstein, P; Trap-Jensen, J; Bagger, H

1983-01-01

Hg (range 18-98) (P less than 0.02). The average washout constant for the three different tracers were approximately equal and correlated statistically significant with the SPP; (2) In 59 legs with AOD, segmental SPP was compared to segmental systolic blood pressures on the thigh, calf, ankle and first...... digit (strain gauge technique). The two different methods correlated statistically significant at all four levels, but the systolic blood pressures were higher than the SPP in particular in diabetic legs; (3) Angiograms in 35 legs with AOD showed that the SPP on the ankle was only consistently decreased...

Higher ambulatory systolic blood pressure independently associated with enlarged perivascular spaces in basal ganglia.

Science.gov (United States)

Yang, Shuna; Yuan, Junliang; Zhang, Xiaoyu; Fan, Huimin; Li, Yue; Yin, Jiangmei; Hu, Wenli

2017-09-01

Enlarged perivascular spaces (EPVS) have been identified as a marker of cerebral small vessel diseases (CSVD). Ambulatory blood pressure (ABP) is the strongest predictor of hypertension-related brain damage. However, the relationship between ABP levels and EPVS is unclear. This study aimed to investigate the association between ABP levels and EPVS by 24-hour ambulatory blood pressure monitoring (ABPM). We prospectively recruited inpatients for physical examinations in our hospital from May 2013 to Jun 2016. 24-hour ABPM data and cranial magnetic resonance imaging information were collected. EPVS in basal ganglia (BG) and centrum semiovale (CSO) were identified and classified into three categories by the severity. White matter hyperintensities were scored by Fazekas scale. Spearman correlation analysis and multiple logistic regression analysis were used to determine the relationship between ABP levels and EPVS. A total of 573 subjects were enrolled in this study. 24-hour, day and night systolic blood pressure (SBP) levels were positively related to higher numbers of EPVS in BG (24-hour SBP: r = 0.23, p blood pressure (DBP) levels increased with an increasing degree of EPVS in CSO (p = 0.04 and 0.049, respectively). But the association disappeared after adjusting for confounders. Spearman correlation analysis indicated that ABP levels were not associated with higher numbers of EPVS in CSO (p > 0.05). DBP levels were not independently associated with the severity of EPVS in BG and CSO. Higher SBP levels were independently associated with EPVS in BG, but not in CSO, which supported EPVS in BG to be a marker of CSVD. Pathogenesis of EPVS in BG and CSO might be different.

Evaluation of single right atrial volume and function with magnetic resonance imaging in children with hypoplastic left heart

Energy Technology Data Exchange (ETDEWEB)

Vijarnsorn, Chodchanok [University of Alberta, Faculty of Medicine and Dentistry, Stollery Children' s Hospital, Edmonton, AB (Canada); Mahidol University, Siriraj Hospital, Bangkok (Thailand); Myers, Kimberley; Patton, David J. [Alberta Children' s Hospital, Section of Pediatric Cardiology, Department of Pediatrics, Department of Pediatrics, Calgary, AB (Canada); Noga, Michelle; Crawley, Cinzia; Tham, Edythe [University of Alberta, Faculty of Medicine and Dentistry, Stollery Children' s Hospital, Edmonton, AB (Canada)

2016-06-15

Standardized methods to evaluate atrial properties in single ventricles are lacking. To determine the feasibility of quantifying right atrial volumes and function in hypoplastic left heart using MRI. We studied 15 infants with hypoplastic left heart prior to Glenn surgery (mean age 4.2 months [standard deviation 0.3]) who underwent cardiac MRI with evaluation of atrial volumes and emptying fraction using monoplane two-chamber, monoplane four-chamber, and biplane methods, all of which were compared to the atrial short-axial oblique stack method. We compared atrial end-diastolic volume, end-systolic volume and emptying fraction among these methods. We analyzed reproducibility of the methods using Bland-Altman plots. Both four-chamber and biplane methods showed high correlations for atrial end-diastolic volume (r = 0.7 and r = 0.8, respectively; P < 0.01) and end-systolic volume (r = 0.8 and r = 0.9, respectively; P < 0.01) with small mean differences (-0.2 ± 2.9 standard deviation [SD] ml and -0.8 ± 1.6 ml, respectively, for atrial end-diastolic volume and -0.8 ± 1.5 ml and -0.9 ± 0.9 ml, respectively, for atrial end-systolic volume). The short-axial oblique method was the most reproducible, followed by the four-chamber method. MRI assessment of atrial volume and function is feasible in hypoplastic left heart and might provide further insight into single-ventricle mechanics. (orig.)

Visit-to-Visit Variability in Blood Pressure and Kidney and Cardiovascular Outcomes in Patients With Type 2 Diabetes and Nephropathy

DEFF Research Database (Denmark)

McMullan, Ciaran J; Lambers Heerspink, Hiddo J; Parving, Hans-Henrik

2014-01-01

-to-visit variability was calculated from the SD of the systolic blood pressure from 4 visits occurring 3-12 months postrandomization. OUTCOMES: The kidney disease outcome was defined as time to confirmed doubling of serum creatinine level, end-stage renal disease, or death; the cardiovascular outcome was defined......BACKGROUND: Increased systolic blood pressure variability between outpatient visits is associated with increased incidence of cardiovascular end points. However, few studies have examined the association of visit-to-visit variability in systolic blood pressure with clinically relevant kidney...... disease outcomes. We analyzed the association of systolic blood pressure visit-to-visit variability with renal and cardiovascular morbidity and mortality among individuals with diabetes and nephropathy. STUDY DESIGN: Observational analysis of IDNT (Irbesartan Diabetic Nephropathy Trial) and the RENAAL...

Perceived Social Standing, Medication Nonadherence, and Systolic Blood Pressure in the Rural South.

Science.gov (United States)

Cummings, Doyle M; Wu, Jia-Rong; Cene, Crystal; Halladay, Jacquie; Donahue, Katrina E; Hinderliter, Alan; Miller, Cassandra; Garcia, Beverly; Penn, Dolly; Tillman, Jim; DeWalt, Darren

2016-01-01

Little is known about how perceived social standing versus traditional socioeconomic characteristics influence medication adherence and blood pressure (BP) among African American and white patients with hypertension in the rural southeastern United States. Perceived social standing, socioeconomic characteristics, self-reported antihypertensive medication adherence, and BP were measured at baseline in a cohort of rural African American and white patients (n = 495) with uncontrolled hypertension attending primary care practices. Multivariate models examined the relationship of perceived social standing and socioeconomic indicators with medication adherence and systolic BP. Medication nonadherence was reported by 40% of patients. Younger age [β = 0.20; P = .001], African American race [β = -0.30; P = .03], and lower perceived social standing [β = 0.08; P = .002] but not sex or traditional socioeconomic characteristics including education and household income, were significantly associated with lower medication adherence. Race-specific analyses revealed that this pattern was limited to African Americans and not observed in whites. In stepwise modeling, older age [β = 0.57, P = .001], African American race [β = 4.4; P = .03], and lower medication adherence [β = -1.7, P = .01] but not gender, education, or household income, were significantly associated with higher systolic BP. Lower perceived social standing and age, but not traditional socioeconomic characteristics, were significantly associated with lower medication adherence in African Americans. Lower medication adherence was associated with higher systolic BP. These findings suggest the need for tailored, culturally relevant medication adherence interventions in rural communities. © 2015 National Rural Health Association.

Spectral analyses of systolic blood pressure and heart rate variability and their association with cognitive performance in elderly hypertensive subjects.

Science.gov (United States)

Santos, W B; Matoso, J M D; Maltez, M; Gonçalves, T; Casanova, M; Moreira, I F H; Lourenço, R A; Monteiro, W D; Farinatti, P T V; Soares, P P; Oigman, W; Neves, M F T; Correia, M L G

2015-08-01

Systolic hypertension is associated with cognitive decline in the elderly. Altered blood pressure (BP) variability is a possible mechanism of reduced cognitive performance in elderly hypertensives. We hypothesized that altered beat-to-beat systolic BP variability is associated with reduced global cognitive performance in elderly hypertensive subjects. In exploratory analyses, we also studied the correlation between diverse discrete cognitive domains and indices of systolic BP and heart rate variability. Disproving our initial hypothesis, we have shown that hypertension and low education, but not indices of systolic BP and heart rate variability, were independent predictors of lower global cognitive performance. However, exploratory analyses showed that the systolic BP variability in semi-upright position was an independent predictor of matrix reasoning (B = 0.08 ± .03, P-value = 0.005), whereas heart rate variability in semi-upright position was an independent predictor of the executive function score (B = -6.36 ± 2.55, P-value = 0.02). We conclude that myogenic vascular and sympathetic modulation of systolic BP do not contribute to reduced global cognitive performance in treated hypertensive subjects. Nevertheless, our results suggest that both systolic BP and heart rate variability might be associated with modulation of frontal lobe cognitive domains, such as executive function and matrix reasoning.

Value of systolic pulmonary arterial pressure as a prognostic factor of death in the systemic sclerosis EUSTAR population

DEFF Research Database (Denmark)

Hachulla, Eric; Clerson, Pierre; Airò, Paolo

2015-01-01

OBJECTIVE: The aim of this study was to assess the prognostic value of systolic pulmonary artery pressure (sPAP) estimated by echocardiography in the multinational European League Against Rheumatism Scleroderma Trial and Research (EUSTAR) cohort. METHODS: Data for patients with echocardiography...

Assessing intravascular volume by difference in pulse pressure in pigs submitted to graded hemorrhage.

Science.gov (United States)

Pestel, Gunther J; Hiltebrand, Luzius B; Fukui, Kimiko; Cohen, Delphine; Hager, Helmut; Kurz, Andrea M

2006-10-01

We assessed changes in intravascular volume monitored by difference in pulse pressure (dPP%) after stepwise hemorrhage in an experimental pig model. Six pigs (23-25 kg) were anesthetized (isoflurane 1.5 vol%) and mechanically ventilated to keep end-tidal CO2 (etCO2) at 35 mmHg. A PA-catheter and an arterial catheter were placed via femoral access. During and after surgery, animals received lactated Ringer's solution as long as they were considered volume responders (dPP>13%). Then animals were allowed to stabilize from the induction of anesthesia and insertion of catheters for 30 min. After stabilization, baseline measurements were taken. Five percent of blood volume was withdrawn, followed by another 5%, and then in 10%-increments until death from exsanguination occurred. After withdrawal of 5% of blood volume, all pigs were considered volume responders (dPP>13%); dPP rose significantly from 6.1+/-3.3% to 19.4+/-4.2%. The regression analysis of stepwise hemorrhage revealed a linear relation between blood loss (hemorrhage in %) and dPP (y=0.99*x+14; R2=0.7764; P<.0001). In addition, dPP was the only parameter that changed significantly between baseline and a blood loss of 5% (P<0.01), whereas cardiac output, stroke volume, heart rate, MAP, central venous pressure, pulmonary artery occlusion pressure, and systemic vascular resistance, respectively, remained unchanged. We conclude that in an experimental hypovolemic pig model, dPP correlates well with blood loss.

Cardiac magnetic resonance imaging for evaluation of non-compaction cardiomyopathy in patients with or without left ventricular systolic dysfunction

International Nuclear Information System (INIS)

Deviggiano, A.; Deschle, H.; Lewkowicz, J.M.; Tajer, C.D.; Carrascosa, P.; Capunay, C.; Vallejos, J.; Stewart Harris, A.

2011-01-01

Background: Non-compaction cardiomyopathy (NCC) is a genetic disorder characterized by deep trabeculations in the ventricular wall, which define recesses communicating with the main ventricular chamber. The prevalence of NCC is greater in symptomatic populations with left ventricular dysfunction; yet, it may also be detected in asymptomatic patients with normal left ventricular function using novel diagnostic tools. However, this condition is under-diagnosed due to a low index of clinical suspicion and to the use of echocardiography classifications based on different diagnostic criteria. The use of cardiac magnetic resonance imaging (CMRI) has established two diagnostic criteria that clearly recognize this disease. Objective: To evaluate the clinical and morphological characteristics of patients with NCC with and without systolic dysfunction undergoing cardiac magnetic resonance imaging (CMRI). Material and Methods: A total of 20 patients with NCC were retrospectively included. The following parameters were determined: left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV); left ventricular end-diastolic diameter (LVEDD); left ventricular end-systolic diameter (LVESD); cardiac mass and left ventricular trabeculations. The distribution of NC myocardium was evaluated according to the model of 17 myocardial segments. Results: Mean myocardial thickness was 13.1 ± 3.3 mm and 3.6 ± 0.6 mm in NC versus normal myocardium, respectively. Patients with left ventricular dysfunction presented increased LVEDD, LVEDV, total cardiac mass, and LV non-compaction and trabeculations. We found a positive correlation and a linear relationship between LVEDD and TLVM (g/m 2 ): r=0.76; r 2 =0.59; p [es

Marinobufagenin is related to elevated central and 24-h systolic blood pressures in young black women: the African-PREDICT Study.

Science.gov (United States)

Strauss, Michél; Smith, Wayne; Wei, Wen; Fedorova, Olga V; Schutte, Aletta E

2018-03-01

Marinobufagenin (MBG) is an endogenous steroidal α1-Na + K + -ATPase inhibitor. Because of its role in sodium handling, MBG has been associated with both antihypertensive and prohypertensive effects in normal physiology and pathology. MBG is positively associated with blood pressure in Dahl salt-sensitive rats exhibiting a similar hypertensive phenotype to black populations, characterized by impaired urinary Na + excretion. However, clinical studies exploring blood pressure (BP)-related effects of MBG in black populations are scant. We determined whether the MBG/Na + ratio (assessing the effectiveness of Na + excretion resistance to MBG) is related to systolic BP (SBP) in young black men and women, compared to whites. We included 331 apparently healthy participants (20-30 years) (42.9% black, 43.8% men) on a habitual diet. We obtained 24-h and central SBP, and 24-h urinary Na + and MBG levels. We found no ethnic differences in MBG, Na + or MBG/Na + . MBG excretion correlated positively with Na + excretion in all groups and to SBP in white men and black women (p ≤ 0.011). In black women only SBP related positively to MBG/Na + in single and multi-variable adjusted regression models: central SBP (R 2  = 0.26; ß = 0.28; p = 0.039), 24-h SBP (R 2  = 0.46; ß = 0.30; p = 0.011), daytime (R 2  = 0.38; ß = 0.28; p = 0.023) and nighttime SBP (R 2  = 0.38; ß = 0.33; p = 0.009). In contrast, inverse associations of MBG/Na + with nighttime SBP were evident in white women (r = -0.20; p = 0.038) but lost significance after multiple adjustments (R 2  = 0.36; ß = -0.13; p = 0.12). We found independent positive associations of SBP with MBG/Na + in black women. This data supports the concept that reduced MBG-mediated Na + excretion can contribute to adverse hemodynamics.

Brain-Heart Pathways to Blood Pressure-Related Hypoalgesia.

Science.gov (United States)

Ottaviani, Cristina; Fagioli, Sabrina; Mattei, Eugenio; Censi, Federica; Edwards, Louisa; Macaluso, Emiliano; Bozzali, Marco; Critchley, Hugo; Calcagnini, Giovanni

2018-03-28

High blood pressure (BP) is associated with reduced pain sensitivity, known as BP-related hypoalgesia. The underlying neural mechanisms remain uncertain, yet arterial baroreceptor signaling, occurring at cardiac systole, is implicated. We examined normotensives using functional neuroimaging (fMRI) and pain stimulation during distinct phases of the cardiac cycle to test the hypothesized neural mediation of baroreceptor-induced attenuation of pain. Eighteen participants (10 women; 32.7 ± 6.5 years) underwent BP monitoring over one week at home, and individual pain thresholds were determined in the lab. Subsequently, participants were administered unpredictable painful and non-painful electrocutaneous shocks (stimulus type), timed to occur either at systole or diastole (cardiac phase) in an event-related design. After each trial, participants evaluated their subjective experience. Subjective pain was lower for painful stimuli administered at systole compared to diastole, F1, 2283 = 4.82; p = 0.03. Individuals with higher baseline BP demonstrated overall lower pain perception, F1, 2164 = 10.47; p < 0.0001. Within the brain, painful stimulation activated somatosensory areas, prefrontal cortex, cingulate cortex, posterior insula, amygdala, and the thalamus. Stimuli delivered during systole (concurrent with baroreceptor discharge) activated areas associated with heightened parasympathetic drive. No stimulus type x cardiac phase interaction emerged except for a small cluster located in the right parietal cortex. We confirm the negative associations between BP and pain, highlighting the antinociceptive impact of baroreceptor discharge. Neural substrates associated with baroreceptor/BP-related hypoalgesia include superior parietal lobule, precentral and lingual gyrus, regions typically involved in the cognitive aspects of pain experience.

Respiratory System Mechanics During Low Versus High Positive End-Expiratory Pressure in Open Abdominal Surgery: A Substudy of PROVHILO Randomized Controlled Trial

NARCIS (Netherlands)

D'Antini, Davide; Huhle, Robert; Herrmann, Jacob; Sulemanji, Demet S.; Oto, Jun; Raimondo, Pasquale; Mirabella, Lucia; Hemmes, Sabrine N. T.; Schultz, Marcus J.; Pelosi, Paolo; Kaczka, David W.; Vidal Melo, Marcos Francisco; Gama de Abreu, Marcelo; Cinnella, Gilda

2018-01-01

In the 2014 PROtective Ventilation using HIgh versus LOw positive end-expiratory pressure (PROVHILO) trial, intraoperative low tidal volume ventilation with high positive end-expiratory pressure (PEEP = 12 cm H2O) and lung recruitment maneuvers did not decrease postoperative pulmonary complications

Adaptation to periodic pressure chamber hypoxia and its influence on systolic and diastolic functions in chronic heart failure

Directory of Open Access Journals (Sweden)

Dmitrieva М.К.

2012-06-01

Full Text Available Research objective is to determine the influence of adaptation method to periodic pressure chamber hypoxia on dynamics of systolic and diastolic functions of myocardium in patients with early stages of chronic heart failure. Materials and Methods: 100 men with post-infarction cardiosclerosis at the age of 40-65 years with I and IIA stages and l-ll functional classes (NYHA of chronic heart failure have been examined. Results: Positive dynamics of systolic and diastolic cardiac functions and other parameters of echocardioscopy under the influence of the hypoxic therapy in comparison with classical physical rehabilitation have been obtained. Furthermore, a more significant effect has been observed in patients with CHF IIA. Conclusion: Improvement in the geometry of the heart has proved that adaptation method to periodic pressure chamber hypoxia could be recommended for rehabilitation of patients with heart failure of early stages.

Thermodynamics of volume-collapse transitions in cerium and related compounds

International Nuclear Information System (INIS)

Bustingorry, S.; Jagla, E.A.; Lorenzana, J.

2005-01-01

We present a non-linear elastic model of a coherent transition with discontinuous volume change in an isotropic solid. The model reproduces the anomalous thermodynamics typical of coherent equilibrium including intrinsic hysteresis (for a pressure driven experiment) and a negative bulk modulus. The novelty of the model is that the statistical mechanics solution can be easily worked out. We find that coherency leads to an infinite-range density-density interaction, which drives classical critical behavior. The pressure width of the hysteresis loop shrinks with increasing temperature, ending at a critical point at a temperature related to the shear modulus. The bulk modulus softens with a 1/2 exponent at the transition even far from the critical point. Many well known features of the phase diagram of Ce and related systems are explained by the model

Effects of hemodialysis on corneal and anterior chamber morphometry and intraocular pressure in patients with end-stage renal disease

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Mehtap Caglayan

Full Text Available ABSTRACT Purpose: To evaluate the effects of hemodialysis (HD on corneal and anterior chamber morphometry, as well as intraocular pressure (IOP in patients with end-stage renal disease. Methods: Fifty right eyes were examined 30 minutes before and after HD. IOP was measured with a Goldmann applanation tonometer, and Ehlers' formula was used to calculate the corrected IOP values. The central corneal thickness (CCT, corneal volume (CV, keratometric values, anterior chamber depth (ACD, aqueous depth (AQD, anterior chamber volume (ACV, and anterior chamber angle (ACA in the nasal and temporal quadrants were measured with a Sirius anterior segment analysis system. Blood urea nitrogen levels, body mass, and systolic and diastolic arterial pressure were also measured before and after HD. Results: The mean age was 60.80 ± 13.38 (range: 35-80 years. The mean uncorrected and corrected IOP values decreased from 18.06 ± 3.91 and 18.31 ± 4.83 mmHg to 16.94 ± 3.87 and 16.95 ± 4.74 mmHg after HD, respectively (p=0.011 and p=0.003, respectively. The mean CCT decreased from 536.38 ± 24.73 to 533.18 ± 27.25 µm (p=0.002, and the mean CV decreased from 57.52 ± 3.15 to 55.68 ± 3.55 mm³ (p0.05 for all values. There were no significant correlations between the ocular and systemic parameters (p>0.05 for all correlations. Conclusions: Uncorrected IOP, corrected IOP, CCT, and CV values decreased after HD, whereas the anterior chamber morphometry values remained similar between the measurements performed before and after HD.

Proceedings of the 1985 pressure vessels and piping conference. Volume PVP-98-8. Fracture, fatigue and advanced mechanics

International Nuclear Information System (INIS)

Short, W.E.; Zamrik, S.Y.

1985-01-01

State-of-the-art engineering practices in pressure vessel and piping technology are the result of continual efforts in the evaluation of problems which have been experienced and the development of appropriate design and analysis methods for those applications. The resulting advances in technology benefit industry with properly engineered, safe, cost-effective pressure vessels and piping systems. To this end, advanced study continues in specialized areas of mechanical engineering such as fracture mechanics, experimental stress analysis, high pressure applications and related material considerations, as well as advanced techniques for evaluation of commonly encountered design problems. This volume is comprised of current technical papers on various aspects of fracture, fatigue and advanced mechanics as related to the design and analysis of pressure vessels and piping

Physiological Responses Associated with Nordic-Walking Training in Systolic Hypertensive Postmenopausal Women

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Latosik Ewelina

2014-12-01

Full Text Available Loss of physical strength and hypertension are among the most pronounced detrimental factors accompanying aging. The aim of this study was to evaluate the influence of a supervised 8-week Nordic-walking training program on systolic blood pressure in systolic-hypertensive postmenopausal women. This study was a randomized control trial on a sample of 24 subjects who did not take any hypertension medications. There was a statistically significant decrease in systolic blood pressure and an increase in lower and upper-body strength in the group following Nordic-walking training. There was a decrease in serum levels of total cholesterol, triglycerides, and low-density cholesterol. The obtained results indicate that an 8-week Nordic-walking program may be efficiently employed for counteracting systolic hypertension through a direct abatement of systolic blood pressure and an increase of maximal aerobic capacity.

Valuation of Normal Range of Ankle Systolic Blood Pressure in Subjects with Normal Arm Systolic Blood Pressure.

Science.gov (United States)

Gong, Yi; Cao, Kai-wu; Xu, Jin-song; Li, Ju-xiang; Hong, Kui; Cheng, Xiao-shu; Su, Hai

2015-01-01

This study aimed to establish a normal range for ankle systolic blood pressure (SBP). A total of 948 subjects who had normal brachial SBP (90-139 mmHg) at investigation were enrolled. Supine BP of four limbs was simultaneously measured using four automatic BP measurement devices. The ankle-arm difference (An-a) on SBP of both sides was calculated. Two methods were used for establishing normal range of ankle SBP: the 99% method was decided on the 99% reference range of actual ankle BP, and the An-a method was the sum of An-a and the low or up limits of normal arm SBP (90-139 mmHg). Whether in the right or left side, the ankle SBP was significantly higher than the arm SBP (right: 137.1 ± 16.9 vs 119.7 ± 11.4 mmHg, P<0.05). Based on the 99% method, the normal range of ankle SBP was 94~181 mmHg for the total population, 84~166 mmHg for the young (18-44 y), 107~176 mmHg for the middle-aged(45-59 y) and 113~179 mmHg for the elderly (≥ 60 y) group. As the An-a on SBP was 13 mmHg in the young group and 20 mmHg in both middle-aged and elderly groups, the normal range of ankle SBP on the An-a method was 103-153 mmHg for young and 110-160 mmHg for middle-elderly subjects. A primary reference for normal ankle SBP was suggested as 100-165 mmHg in the young and 110-170 mmHg in the middle-elderly subjects.

Simultaneous inter-arm and inter-leg systolic blood pressure differences to diagnose peripheral artery disease: a diagnostic accuracy study.

Science.gov (United States)

Herráiz-Adillo, Ángel; Soriano-Cano, Alba; Martínez-Hortelano, José Alberto; Garrido-Miguel, Miriam; Mariana-Herráiz, Julián Ángel; Martínez-Vizcaíno, Vicente; Notario-Pacheco, Blanca

2018-04-01

Inter-arm systolic blood pressure differences (IASBPD) and inter-leg systolic blood pressure differences (ILSBPD) have arisen as potential tools to detect peripheral artery disease (PAD) and individuals at high cardiovascular risk. This study aims to evaluate the diagnostic accuracy of IASBPD and ILSBPD to detect PAD, and whether IASBPD or ILSBPD improves diagnostic accuracy of the oscillometric ankle-brachial index (ABI). In this prospective study, eligible for inclusion were consecutive adults, with at least one of the following cardiovascular risk factors: diabetes, dyslipidemia, hypertension, smoking habit or age ≥65. IASBPD, ILSBPD and ankle-brachial index (ABI) were measured in all participants through four-limb simultaneous oscillometric measurements and compared with Doppler ABI (reference test, positive cut-off: ≤ 0.9). Of 171 subjects included, PAD was confirmed in 23 and excluded in 148. Thirteen and 38 subjects had IASBPD and ILSBPD ≥10 mmHg, respectively. Pearson correlation with Doppler ABI of IASBPD and ILSBPD was 0.073 (P = .343) and -0.628 (P blood pressure measurements in upper limbs are not possible.

Choice of marker for assessment of RV dysfunction in acute pulmonary embolism : NT-proBNP, pulmonary artery systolic pressure, mean arterial pressure, or blood pressure index.

Science.gov (United States)

Ates, H; Ates, I; Kundi, H; Yilmaz, F M

2017-12-01

We aimed to examine the value of NT-proBNP, pulmonary artery systolic pressure (PASP), blood pressure index (BPI), and mean arterial pressure (MAP) in the determination of right ventricular dysfunction (RVD) in patients with acute pulmonary embolism (APE). A total of 547 patients diagnosed with APE were included in the study. Demographic characteristics and comorbid conditions of patients were recorded in patient files. For blood pressure measurement, a calibrated digital blood pressure monitor was used at regular intervals. Blood samples were taken from patients at the time of admission for hemogram, biochemical, and hemostasis blood tests. Echocardiography was performed on all patients to detect RVD and evaluate pulmonary artery pressure. PASP (p blood pressure (p blood cell (p AUC ± SE = 0.975 ± 0.006; p < 0.001) was found to be the best predictor of RVD with a higher sensitivity (92.8%) and specificity (100%). We found that BPI had a better diagnostic discrimination for RVD compared with PASP and NT-proBNP.

Relation between birth weight and blood pressure: longitudinal study of infants and children

NARCIS (Netherlands)

L.J. Launer (Lenore); D.E. Grobbee (Diederick); A. Hofman (Albert)

1993-01-01

textabstractOBJECTIVE--To study the relation between birth weight and systolic blood pressure in infancy and early childhood. DESIGN--Longitudinal study of infants from birth to 4 years of age. SETTING--A middle class community in the Netherlands. PARTICIPANTS--476

A high-sugar and high-fat diet impairs cardiac systolic and diastolic function in mice.

Science.gov (United States)

Carbone, Salvatore; Mauro, Adolfo G; Mezzaroma, Eleonora; Kraskauskas, Donatas; Marchetti, Carlo; Buzzetti, Raffaella; Van Tassell, Benjamin W; Abbate, Antonio; Toldo, Stefano

2015-11-01

Heart failure (HF) is a clinical syndrome characterized by dyspnea, fatigue, exercise intolerance and cardiac dysfunction. Unhealthy diet has been associated with increased risk of obesity and heart disease, but whether it directly affects cardiac function, and promotes the development and progression of HF is unknown. We fed 8-week old male or female CD-1 mice with a standard diet (SD) or a diet rich in saturated fat and sugar, resembling a "Western" diet (WD). Cardiac systolic and diastolic function was measured at baseline and 4 and 8 weeks by Doppler echocardiography, and left ventricular (LV) end-diastolic pressure (EDP) by cardiac catheterization prior to sacrifice. An additional group of mice received WD for 4 weeks followed by SD (wash-out) for 8 weeks. WD-fed mice experienced a significant decreased in LV ejection fraction (LVEF), reflecting impaired systolic function, and a significant increase in isovolumetric relaxation time (IRT), myocardial performance index (MPI), and LVEDP, showing impaired diastolic function, without any sex-related differences. Switching to a SD after 4 weeks of WD partially reversed the cardiac systolic and diastolic dysfunction. A diet rich in saturated fat and sugars (WD) impairs cardiac systolic and diastolic function in the mouse. Further studies are required to define the mechanism through which diet affects cardiac function, and whether dietary interventions can be used in patients with, or at risk for, HF. Published by Elsevier Ireland Ltd.

Low Pressure Robot-assisted Radical Prostatectomy With the AirSeal System at OLV Hospital: Results From a Prospective Study.

Science.gov (United States)

La Falce, Sabrina; Novara, Giacomo; Gandaglia, Giorgio; Umari, Paolo; De Naeyer, Geert; D'Hondt, Frederiek; Beresian, Jean; Carette, Rik; Penicka, Martin; Mo, Yujiing; Vandenbroucke, Geert; Mottrie, Alexandre

2017-12-01

Limited studies examined effects of pneumoperiotneum during robot-assisted radical prostatectomy (RARP) and with AirSeal. The aim of this study was to assess the effect on hemodynamics of a lower pressure pneumoperitoneum (8 mmHg) with AirSeal, during RARP in steep Trendelenburg 45° (ST). This is an institutional review board-approved, prospective, interventional, single-center study including patients treated with RARP at OLV Hospital by one extremely experienced surgeon (July 2015-February 2016). Intraoperative monitoring included: arterial pressure, central venous pressure, cardiac output, heart rate, stroke volume, systemic vascular resistance, intrathoracic pressure, airways pressures, left ventricular end-diastolic and end-systolic areas/volumes and ejection fraction, by transesophageal echocardiography, an esophageal catheter, and FloTrac/Vigileo system. Measurements were performed after induction of anesthesia with patient in horizontal (T0), 5 minutes after 8 mmHg pneumoperitoneum (TP), 5 minutes after ST (TT1) and every 30 minutes thereafter until the end of surgery (TH). Parameters modification at the prespecified times was assessed by Wilcoxon and Friedman tests, as appropriate. All analyses were performed by SPSS v. 23.0. A total of 53 consecutive patients were enrolled. The mean patients age was 62.6 ± 6.9 years. Comorbidity was relatively limited (51% with Charlson Comorbidity Index as low as 0). Despite the ST, working always at 8 mmHg with AirSeal, only central venous pressure and mean airways pressure showed a statistically significant variation during the operative time. Although other significant hemodynamic/respiratory changes were observed adding pneumoperitoneum and then ST, all variables remained always within limits safely manageable by anesthesiologists. The combination of ST, lower pressure pneumoperitoneum and extreme surgeon's experience enables to safely perform RARP. Copyright © 2017 Elsevier Inc. All rights reserved.

Iodine status and its correlations with age, blood pressure, and thyroid volume in South Indian women above 35 years of age (Amrita Thyroid Survey

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Vadayath Usha Menon

2011-01-01

Full Text Available Background: Thyroid disorders are more commonly seen among females and the prevalence increases with age. There is no population data from India focusing on iodine levels and their correlations with thyroid volume and other factors in adult women. Aim: This study was designed to establish the iodine status and its relation with various factors including thyroid volume measured by ultrasound among the females of Kerala. Materials and Methods: This was a cross sectional house to house survey among the females above 35 years of age in a randomly selected urban area in Cochin Corporation, Kerala State, India. Selected subjects were interviewed, examined and blood and urine tests were done. Thyroid volume was calculated using ultrasound. Results: Among the 508 subjects who participated in the checkup, 471 subjects were included for analysis. Mean age was 50.3 + 10.7 years and 53.2% were postmenopausal. A total of 98% of the subjects were using iodized salt and median urinary iodine excretion (UIE was 162.6 mcg/l. UIE had negative correlation with age and systolic blood pressure (BP, but had no correlation with thyroid volume (TV, thyroid nodularity, free thyroxine 4 (FT4, thyroid stimulating hormone (TSH or anti thyroid peroxidase (TPO levels. Iodine deficiency was more commonly seen in subjects with hypertension and also among postmenopausal females. Conclusions: This study showed that females > 35 years were iodine sufficient, though one third of the subjects had UIE levels less than the recommended level. Iodine levels had significant negative correlation with age and systolic BP and no correlation with thyroid volume or biochemical parameters. Iodine deficiency was significantly higher in subjects with new and known hypertension and this relation merits further evaluation.

Nesfatin-1 and Vitamin D levels may be associated with systolic and diastolic blood pressure values and hearth rate in polycystic ovary syndrome.

Science.gov (United States)

Sahin, Figen Kir; Sahin, Serap Baydur; Ural, Ulku Mete; Cure, Medine Cumhur; Senturk, Senol; Tekin, Yesim Bayoglu; Balik, Gulsah; Cure, Erkan; Yuce, Suleyman; Kirbas, Aynur

2015-07-09

Obesity, insulin resistance (IR), inflammation, and hyperandrogenism may lead to polycystic ovary syndrome (PCOS) and hypertension. Nesfatin-1 (N1) may be related to IR, obesity, and hypertension. Furthermore, a vitamin D (VD) deficiency is associated with hypertension and PCOS. We aimed to investigate N1 and VD levels in PCOS that have an effect on systolic and diastolic blood pressure (BP) and heart rate (HR).This study included 54 patients with PCOS and 48 age-body mass index (BMI)-matched healthy controls. PCOS was diagnosed according to clinical practice guidelines. Ferriman-Gallwey scores (FGS) were calculated, while N1, VD, and other hormonal and biochemical parameters were measured for all subjects. Systolic and diastolic BP was measured as well. HR was calculated using an electrocardiogram.The levels of N1 (p < 0.001), high-sensitivity C-reactive protein (hs-CRP) (p = 0.036), homeostasis model assessment as an index of insulin resistance (HOMA-IR) (p < 0.001), systolic (p < 0.001) and diastolic (p < 0.001) BP and HR (p < 0.001) in the PCOS group were significantly higher than in the control group. However, the VD levels of the PCOS group were lower than the control group (p = 0.004). N1 had a strong positive correlation with BMI, HOMA-IR, hs-CRP, luteinizing hormone, systolic and diastolic BP, and HR. VD levels were negatively correlated with HOMA-IR and luteinizing hormone.Elevated N1 and decreased VD levels may be related to the presence of high-normal BP or hypertension in PCOS subjects.  N1 level may be associated with an increased BP due to its relation to inflammation and IR.

Decreased systolic blood pressure is associated with increased risk of all-cause mortality in patients with type 2 diabetes and renal impairment: A nationwide longitudinal observational study of 27,732 patients based on the Swedish National Diabetes Register.

Science.gov (United States)

Svensson, Maria K; Afghahi, Henri; Franzen, Stefan; Björk, Staffan; Gudbjörnsdottir, Soffia; Svensson, Ann-Marie; Eliasson, Björn

2017-05-01

Previous studies have shown a U-shaped relationship between systolic blood pressure and risk of all-cause of mortality in patients with type 2 diabetes and renal impairment. To evaluate the associations between time-updated systolic blood pressure and time-updated change in systolic blood pressure during the follow-up period and risk of all-cause mortality in patients with type 2 diabetes and renal impairment. A total of 27,732 patients with type 2 diabetes and renal impairment in the Swedish National Diabetes Register were followed for 4.7 years. Time-dependent Cox models were used to estimate risk of all-cause mortality. Time-updated mean systolic blood pressure is the average of the baseline and the reported post-baseline systolic blood pressures. A time-updated systolic blood pressure blood pressure > 10 mmHg between the last two observations was associated with higher risk of all-cause mortality (-10 to -25 mmHg; hazard ratio: 1.24, 95% confidence interval: 1.17-1.32). Both low systolic blood pressure and a decrease in systolic blood pressure during the follow-up are associated with a higher risk of all-cause mortality in patients with type 2 diabetes and renal impairment.

Initial Systolic Time Interval (ISTI) as a Predictor of Intradialytic Hypotension (IDH)

International Nuclear Information System (INIS)

Biesheuvel, J D; Verdaasdonk, R M; Meijer, JH; Vervloet, M G

2013-01-01

In haemodialysis treatment the clearance and volume control by the kidneys of a patient are partially replaced by intermittent haemodialysis. Because this artificial process is performed on a limited time scale, unphysiological imbalances in the fluid compartments of the body occur, that can lead to intradialytic hypotensions (IDH). An IDH endangers the efficacy of the haemodialysis session and is associated with dismal clinical endpoints, including mortality. A diagnostic method that predicts the occurrence of these drops in blood pressure could facilitate timely measures for the prevention of IDH. The present study investigates whether the Initial Systolic Time Interval (ISTI) can provide such a diagnostic method. The ISTI is defined as the time difference between the R-peak in the electrocardiogram (ECG) and the C-wave in the impedance cardiogram (ICG) and is considered to be a non-invasive assessment of the time delay between the electrical and mechanical activity of the heart. This time delay has previously been found to depend on autonomic nervous function as well as preload of the heart. Therefore, it can be expected that ISTI may predict an imminent IDH caused by a low circulating blood volume. This ongoing observational clinical study investigates the relationship between changes in ISTI and subsequent drops in blood pressure during haemodialysis. A registration of a complicated dialysis showed a significant correlation between a drop in blood pressure, a decrease in relative blood volume and a substantial increase in ISTI. An uncomplicated dialysis, in which also a considerable amount of fluid was removed, showed no correlations. Both, blood pressure and ISTI remained stable. In conclusion, the preliminary results of the present study show a substantial response of ISTI to haemodynamic instability, indicating an application in optimization and individualisation of the dialysis process.

Diastolic chamber properties of the left ventricle assessed by global fitting of pressure-volume data: improving the gold standard of diastolic function.

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Bermejo, Javier; Yotti, Raquel; Pérez del Villar, Candelas; del Álamo, Juan C; Rodríguez-Pérez, Daniel; Martínez-Legazpi, Pablo; Benito, Yolanda; Antoranz, J Carlos; Desco, M Mar; González-Mansilla, Ana; Barrio, Alicia; Elízaga, Jaime; Fernández-Avilés, Francisco

2013-08-15

In cardiovascular research, relaxation and stiffness are calculated from pressure-volume (PV) curves by separately fitting the data during the isovolumic and end-diastolic phases (end-diastolic PV relationship), respectively. This method is limited because it assumes uncoupled active and passive properties during these phases, it penalizes statistical power, and it cannot account for elastic restoring forces. We aimed to improve this analysis by implementing a method based on global optimization of all PV diastolic data. In 1,000 Monte Carlo experiments, the optimization algorithm recovered entered parameters of diastolic properties below and above the equilibrium volume (intraclass correlation coefficients = 0.99). Inotropic modulation experiments in 26 pigs modified passive pressure generated by restoring forces due to changes in the operative and/or equilibrium volumes. Volume overload and coronary microembolization caused incomplete relaxation at end diastole (active pressure > 0.5 mmHg), rendering the end-diastolic PV relationship method ill-posed. In 28 patients undergoing PV cardiac catheterization, the new algorithm reduced the confidence intervals of stiffness parameters by one-fifth. The Jacobian matrix allowed visualizing the contribution of each property to instantaneous diastolic pressure on a per-patient basis. The algorithm allowed estimating stiffness from single-beat PV data (derivative of left ventricular pressure with respect to volume at end-diastolic volume intraclass correlation coefficient = 0.65, error = 0.07 ± 0.24 mmHg/ml). Thus, in clinical and preclinical research, global optimization algorithms provide the most complete, accurate, and reproducible assessment of global left ventricular diastolic chamber properties from PV data. Using global optimization, we were able to fully uncouple relaxation and passive PV curves for the first time in the intact heart.

Significance of left ventricular volume measurement after heart transplantation using radionuclide techniques

International Nuclear Information System (INIS)

Novitzky, D.; Cooper, D.; Boniaszczuk, J.

1985-01-01

Multigated equilibrium blood pool scanning using Technetium 99m labeled red blood cells was used to measure left ventricular volumes in three heterotopic and one orthotopic heart transplant recipient(s). Simultaneously, an endomyocardial biopsy was performed and the degree of acute rejection was assessed by a histological scoring system. The scores were correlated to changes in ejection fraction and heart rate. Technetium 99m scanning data were pooled according to the endomyocardial biopsy score: no rejection; mild rejection; moderate rejection, and severe rejection. In each group, the median of the left ventricular volume parameters was calculated and correlated with the endomyocardial biopsy score, using a non-parametric one-way analysis of variance. A decrease in stroke volume correlated best with the endomyocardial biopsy score during acute rejection. A decrease in end-diastolic left ventricular volumes did not correlate as well. Changes in the end-systolic left ventricular volumes were not statistically significant, but using a simple correlation between end-systolic left ventricular volumes and endomyocardial biopsy the correlation reached significance. Changes in left ventricular volumes measured by Technetium 99m scanning may be useful to confirm the presence or absence of acute rejection in patients with heart grafts

Evaluation of left ventricular volumes measured by magnetic resonance imaging

DEFF Research Database (Denmark)

Møgelvang, J; Thomsen, C; Mehlsen, J

1986-01-01

Left ventricular end-diastolic and end-systolic volumes were determined in 17 patients with different levels of left ventricular function by magnetic resonance imaging (MRI). A 1.5 Tesla Magnet was used obtaining ECG triggered single and multiple slices. Calculated cardiac outputs were compared...

Quantitative assessment of left ventricular systolic function using 3-dimensional echocardiography

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Rahul Mehrotra

2013-09-01

Full Text Available Assessment of left ventricular systolic function is the commonest and one of the most important indications for performance of echocardiography. It is important for prognostication, determination of treatment plan, for decisions related to expensive device therapies and for assessing response to treatment. The current methods based on two-dimensional echocardiography are not reliable, have high degree of inter-observer and intra-observer variability and are based on presumptions about the geometry of left ventricle (LV. Real-time three-dimensional echocardiography (RT3DE on the other hand is fast, easy, accurate, relatively operator independent and is not based on any assumptions related to the shape of LV. Owing to these advantages, it is the Echocardiographic modality of choice for assessment of systolic function of the LV. We describe here a step by step approach to evaluation of LV volumes, ejection fraction, regional systolic function and Dyssynchrony analysis based on RT3DE. It has been well validated in clinical studies and is rapidly being incorporated in routine clinical practice.

Cognitive Function and Kidney Disease: Baseline Data From the Systolic Blood Pressure Intervention Trial (SPRINT).

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Weiner, Daniel E; Gaussoin, Sarah A; Nord, John; Auchus, Alexander P; Chelune, Gordon J; Chonchol, Michel; Coker, Laura; Haley, William E; Killeen, Anthony A; Kimmel, Paul L; Lerner, Alan J; Oparil, Suzanne; Saklayen, Mohammad G; Slinin, Yelena M; Wright, Clinton B; Williamson, Jeff D; Kurella Tamura, Manjula

2017-09-01

Chronic kidney disease is common and is associated with cardiovascular disease, cerebrovascular disease, and cognitive function, although the nature of this relationship remains uncertain. Cross-sectional cohort using baseline data from the Systolic Blood Pressure Intervention Trial (SPRINT). Participants in SPRINT, a randomized clinical trial of blood pressure targets in older community-dwelling adults with cardiovascular disease, chronic kidney disease, or high cardiovascular disease risk and without diabetes or known stroke, who underwent detailed neurocognitive testing in the cognition substudy, SPRINT-Memory and Cognition in Decreased Hypertension (SPRINT-MIND). Urine albumin-creatinine ratio (ACR) and estimated glomerular filtration rate (eGFR). Cognitive function, a priori defined as 5 cognitive domains based on 11 cognitive tests using z scores, and abnormal white matter volume quantified by brain magnetic resonance imaging. Of 9,361 SPRINT participants, 2,800 participated in SPRINT-MIND and 2,707 had complete data; 637 had brain imaging. Mean age was 68 years, 37% were women, 30% were black, and 20% had known cardiovascular disease. Mean eGFR was 70.8±20.9mL/min/1.73m 2 and median urine ACR was 9.7 (IQR, 5.7-22.5) mg/g. In adjusted analyses, higher ACR was associated with worse global cognitive function, executive function, memory, and attention, such that each doubling of urine ACR had the same association with cognitive performance as being 7, 10, 6, and 14 months older, respectively. Lower eGFR was independently associated with worse global cognitive function and memory. In adjusted models, higher ACR, but not eGFR, was associated with larger abnormal white matter volume. Cross-sectional only, no patients with diabetes were included. In older adults, higher urine ACR and lower eGFR have independent associations with global cognitive performance with different affected domains. Albuminuria concurrently identifies a higher burden of abnormal brain

A PILOT STUDY ON THE EFFECTS OF MAGNESIUM SUPPLEMENTATION WITH HIGH AND LOW HABITUAL DIETARY MAGNESIUM INTAKE ON RESTING AND RECOVERY FROM AEROBIC AND RESISTANCE EXERCISE AND SYSTOLIC BLOOD PRESSURE

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Lindsy S. Kass

2013-03-01

Full Text Available The effects of magnesium supplementation on blood pressure (BP have been studied for over 25 years and results have been inconsistent. Blood pressure reductions in randomized studies have varied from 12 mmHg reductions to no reduction. The objective of this pilot intervention was to investigate the effect of magnesium supplementation on systolic blood pressure whilst resting and during recovery from aerobic and resistance exercise and on performance. A further objective was to see whether the effect of a high vs low habitual dietary magnesium intake affected these results. Sixteen male volunteers were randomly assigned to either a 300 mg·d-1 magnesium oxide supplementation (MO or a control group (CG for 14 days. Resting blood pressure (BP and heart rate (HR were measured before subjects performed a maximal 30 minute cycle, immediately followed by three x 5 second isometric bench press, both at baseline and after the intervention. Blood pressure and heart rate were recorded immediately post exercise and after five minutes recovery. A 3 day food diary was recorded for all subjects to measure dietary magnesium intake. At the end of the intervention, the supplemented group, had a reduction in mean resting systolic BP by 8.9 mmHg (115.125 ± 9.46 mmHg, p = 0.01 and post exercise by 13 mmHg (122.625 ± 9. 88 mmHg, p = 0.01. Recovery BP was 11.9 mmHg lower in the intervention group compared to control (p = 0.006 and HR decreased by 7 beats per minute in the experimental group (69.0 ± 11.6 bpm, p = 0. 02. Performance indicators did not change within and between the groups. Habitual dietary magnesium intake affected both resting and post exercise systolic BP and the subsequent effect of the magnesium supplementation. These results have an implication in a health setting and for health and exercise but not performance.

Effect of Self-monitoring and Medication Self-titration on Systolic Blood Pressure in Hypertensive Patients at High Risk of Cardiovascular Disease

OpenAIRE

McManus, Richard J.; Mant, Jonathan; Haque, M. Sayeed; Bray, Emma P.; Bryan, Stirling; Greenfield, Sheila M.; Jones, Miren I.; Jowett, Sue; Little, Paul; Penaloza, Cristina; Schwartz, Claire; Shackleford, Helen; Shovelton, Claire; Varghese, Jinu; Williams, Bryan

2014-01-01

IMPORTANCE: Self-monitoring of blood pressure with self-titration of antihypertensives (self-management) results in lower blood pressure in patients with hypertension, but there are no data about patients in high-risk groups.\\ud \\ud OBJECTIVE: To determine the effect of self-monitoring with self-titration of antihypertensive medication compared with usual care on systolic blood pressure among patients with cardiovascular disease, diabetes, or chronic kidney disease.\\ud \\ud DESIGN, SETTING, AN...

Right ventricular function after acute myocardial infarction: dependence upon infarct related coronary artery

International Nuclear Information System (INIS)

Cho, Ihn Ho; Chun, Kyung A; Won, Kyu Chang; Lee, Hyung Woo; Hong, Geu Ru; Park, Jong Seon; Shin, Dong Gu; Kim, Young Jo; Shim, Bong Sub

2004-01-01

We studied to know the relation between right ventricular function and infarct-related artery after acute myocardial infarction. The right and left ventricular function after a first myocardial infarction was assessed ECG-gated blood pool single photon emission computed tomography (GBPS) algorithms (Cedars-Sinai Medical Center, Los Angels, Calif) (12 after LAD related infarction (group 1) and 15 after RCA related infarction (group 2)). The left ventricular ejection fraction, end-diastolic volume and end-systolic volume did not differ significantly between two groups( group 1 vs 2 :LVEF 50.8% vs 55.1%. LVEDV=73.2 vs 79.7 ml, LVESV=38 vs 44 ml : P>0.05), but right ventricular ejection fraction, end-diastolic volume and end-systolic volume were significantly different after anterior myocardial infarction between two groups( group 1 vs 2 : RVEF=57.3% vs 46.3%. RVEDV=56.4 vs 95.1 ml, RVESV=25.6 vs 54.6ml : P<0.05). There was evidence of right ventricular dilatation in the group with RCA related infarction. Six with inferior infarction had abnormal right ventricular ejection fractions (< 40%). The relation between right and left ventricular ejection fractions was markedly different in the two groups. In the group with RCA related infarction there was a significant linear relation between right and left ventricular ejection fraction(R=0.5). Whereas in the group with LAD related infarction there was not (R=-0.3). Thus right ventricular dysfunction commonly occurs after RCA related infarction. Right ventricular impairment is related after RCA related infarction, but are independent after LAD related infarction. Finally, the different effects of LAD and RCA related infarction on right ventricular function may be explained by site of the myocardial wall involvement after infarction

Blood pressure, left ventricular geometry, and systolic function in children exposed to inorganic arsenic.

Science.gov (United States)

Osorio-Yáñez, Citlalli; Ayllon-Vergara, Julio C; Arreola-Mendoza, Laura; Aguilar-Madrid, Guadalupe; Hernández-Castellanos, Erika; Sánchez-Peña, Luz C; Del Razo, Luz M

2015-06-01

Inorganic arsenic (iAs) is a ubiquitous element present in the groundwater worldwide. Cardiovascular effects related to iAs exposure have been studied extensively in adult populations. Few epidemiological studies have been focused on iAs exposure-related cardiovascular disease in children. In this study we investigated the association between iAs exposure, blood pressure (BP), and functional and anatomical echocardiographic parameters in children. A cross-sectional study of 161 children between 3 and 8 years was conducted in Central Mexico. The total concentration of arsenic (As) species in urine (U-tAs) was determined by hydride generation-cryotrapping-atomic absorption spectrometry and lifetime iAs exposure was estimated by multiplying As concentrations measured in drinking water by the duration of water consumption in years (LAsE). BP was measured by standard protocols, and M-mode echocardiographic parameters were determined by ultrasonography. U-tAs concentration and LAsE were significantly associated with diastolic (DBP) and systolic blood pressure (SBP) in multivariable linear regression models: DBP and SBP were 0.013 (95% CI: 0.002, 0.024) and 0.021 (95% CI: 0.004, 0.037) mmHg higher in association with each 1-ng/mL increase in U-tAs (p 620 compared with 41% (95% CI: -6.44, -0.37) lower, respectively, in children with U-tAs > 70 ng/mL compared with iAs was significantly associated with higher BP and LVM and with lower EF in our study population of Mexican children.

Hyperinflation and intrinsic positive end-expiratory pressure: less room to breathe.

Science.gov (United States)

Krieger, Bruce P

2009-01-01

Clinically, the symptoms and limited exercise capabilities of patients with chronic obstructive pulmonary disease (COPD) correlate better with changes in lung volumes than with airflow measurements. The realization of the clinical importance of hyperinflation has been overshadowed for decades by the use of forced expiratory volume during 1 s (FEV(1)) and the ratio of the FEV(1) to the forced expiratory vital capacity (FEV(1)/FVC) to categorize the severity and progression of COPD. Hyperinflation is defined as an elevation in the end-expiratory lung volume or functional residual capacity. When severe hyperinflation encroaches upon inspiratory capacity and limits vital capacity, it results in elevated intrinsic positive end-expiratory pressure (PEEPi) that places the diaphragm at a mechanical disadvantage and increases the work of breathing. Severe hyperinflation is the major physiologic cause of the resulting hypercarbic respiratory failure and patients' inability to transition (i.e. wean) from mechanical ventilatory support to spontaneous breathing. This paper reviews the basic physiologic principles of hyperinflation and its clinical manifestations as demonstrated by PEEPi. Also reviewed are the adverse effects of hyperinflation and PEEPi in critically ill patients with COPD, and methods for minimizing or counterbalancing these effects. Copyright 2009 S. Karger AG, Basel.

Doppler echocardiographic study in adolescents and young adults with sickle cell anemia

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Wolney de Andrade Martins

1999-12-01

Full Text Available OBJECTIVE: Anatomical and functional assessment of the heart through Doppler and echocardiography in patients with cell anemia (SCA. METHODS: Twenty-five patients with SCA and ages ranging from 14 to 45 years were prospectively studied in a comparison with 25 healthy volunteers. All of them underwent clinical and laboratory evaluation and Doppler echocardiography as well.The measurements were converted into body surface indices. RESULTS: There were increases in all chamber diameters and left ventricle (LV mass of the SCA patients. It was characterised an eccentric hypertrophy of the left ventricle. The preload was increased (left ventricle end-diastolic volume and the afterload was decreased (diastolic blood pressure, peripheral vascular resistance and end-systolic parietal stress ESPS. The cardiac index was increased due to the stroke volume. The ejection fraction and the percentage of the systolic shortening , as well as the systolic time intervals of the LV were equivalent. The isovolumetric contraction period of the LV was increased. The mitral E-septum distance and the end-systolic volume index (ESVi were increased. The ESPS/ESVi ratio,a loading independent parameter, was decreased in SCA, suggesting systolic dysfunction. No significant differences in the diastolic function or in the pulmonary pressure occurred. CONCLUSION: Chamber dilations, eccentric hypertrophy and systolic dysfunction confirm the evidence of the literature in characterizing a sickle cell anemia cardiomyopathy.

Association of physical activity with a systolic blood pressure difference between arms in older people.

Science.gov (United States)

Sato, Koichi; Sugiura, Tomonori; Ohte, Nobuyuki; Dohi, Yasuaki

2018-01-01

A increase in interarm systolic blood pressure difference (IASBPD) is believed to lead to increased risk of cardiovascular disease and to be a predictor of future cardiovascular events. The purpose of the present study was to test the hypothesis that an increased IASBPD is associated with reduced physical activity in older people. Older people who used a geriatric health services facility (n = 147, mean age 83.3 years) were enrolled. The prevalence of IASBPD in individuals with different levels of physical activity and factors that have a crucial effect on IASBPD were investigated. The study participants were divided into three groups according to their physical activity; ambulant persons (group A), wheelchair users (group B) and bedridden persons (group C). Blood pressure around the both brachiums was simultaneously measured using two automated devices. An IASBPD of ≥10 mmHg was considered to be significant IASBPD. The median IASBPD was 4.5 mmHg in the present study participants, and 28 participants (19.0%) had an IASBPD ≥10 mmHg. The IASBPD in group C was greater than that in group A or B. Multivariate linear regression analysis showed that physical activity was the independent predictor of IASBPD after adjustment for possible factors. Furthermore, a logistic regression analysis with the end-point of significant IASBPD showed that physical activity is an independent predictor of significant IASBPD. Physical activity simply assessed by moving ability can predict IASBPD in older individuals. In older people, reduced physical activity might indicate the progression of silent or clinical atherosclerosis and an increased risk of cardiovascular disease. Geriatr Gerontol Int 2018; 18: 95-100. © 2017 Japan Geriatrics Society.

Thermodynamic volume and the extended Smarr relation

Energy Technology Data Exchange (ETDEWEB)

Hyun, Seungjoon; Jeong, Jaehoon; Park, Sang-A; Yi, Sang-Heon [Department of Physics, College of Science, Yonsei University,Seoul 120-749 (Korea, Republic of)

2017-04-10

We continue to explore the scaling transformation in the reduced action formalism of gravity models. As an extension of our construction, we consider the extended forms of the Smarr relation for various black holes, adopting the cosmological constant as the bulk pressure as in some literatures on black holes. Firstly, by using the quasi-local formalism for charges, we show that, in a general theory of gravity, the volume in the black hole thermodynamics could be defined as the thermodynamic conjugate variable to the bulk pressure in such a way that the first law can be extended consistently. This, so called, thermodynamic volume can be expressed explicitly in terms of the metric and field variables. Then, by using the scaling transformation allowed in the reduced action formulation, we obtain the extended Smarr relation involving the bulk pressure and the thermodynamic volume. In our approach, we do not resort to Euler’s homogeneous scaling of charges while incorporating the would-be hairy contribution without any difficulty.

Prognostic Effect of the Nocturnal Blood Pressure Fall in Hypertensive Patients: The Ambulatory Blood Pressure Collaboration in Patients With Hypertension (ABC-H) Meta-Analysis.

Science.gov (United States)

Salles, Gil F; Reboldi, Gianpaolo; Fagard, Robert H; Cardoso, Claudia R L; Pierdomenico, Sante D; Verdecchia, Paolo; Eguchi, Kazuo; Kario, Kazuomi; Hoshide, Satoshi; Polonia, Jorge; de la Sierra, Alejandro; Hermida, Ramon C; Dolan, Eamon; O'Brien, Eoin; Roush, George C

2016-04-01

The prognostic importance of the nocturnal systolic blood pressure (SBP) fall, adjusted for average 24-hour SBP levels, is unclear. The Ambulatory Blood Pressure Collaboration in Patients With Hypertension (ABC-H) examined this issue in a meta-analysis of 17 312 hypertensives from 3 continents. Risks were computed for the systolic night-to-day ratio and for different dipping patterns (extreme, reduced, and reverse dippers) relative to normal dippers. ABC-H investigators provided multivariate adjusted hazard ratios (HRs), with and without adjustment for 24-hour SBP, for total cardiovascular events (CVEs), coronary events, strokes, cardiovascular mortality, and total mortality. Average 24-hour SBP varied from 131 to 140 mm Hg and systolic night-to-day ratio from 0.88 to 0.93. There were 1769 total CVEs, 916 coronary events, 698 strokes, 450 cardiovascular deaths, and 903 total deaths. After adjustment for 24-hour SBP, the systolic night-to-day ratio predicted all outcomes: from a 1-SD increase, summary HRs were 1.12 to 1.23. Reverse dipping also predicted all end points: HRs were 1.57 to 1.89. Reduced dippers, relative to normal dippers, had a significant 27% higher risk for total CVEs. Risks for extreme dippers were significantly influenced by antihypertensive treatment (Panalysis of hypertensive patients, the nocturnal BP fall provided substantial prognostic information, independent of 24-hour SBP levels. © 2016 American Heart Association, Inc.

Hypertension Treatment and Concern About Falling: Baseline Data from the Systolic Blood Pressure Intervention Trial.

Science.gov (United States)

Berlowitz, Dan R; Breaux-Shropshire, Tonya; Foy, Capri G; Gren, Lisa H; Kazis, Lewis; Lerner, Alan J; Newman, Jill C; Powell, James R; Riley, William T; Rosman, Robert; Wadley, Virginia G; Williams, Julie A

2016-11-01

To determine the extent of concern about falling in older adults with hypertension, whether lower blood pressure (BP) and greater use of antihypertensive medications are associated with greater concern about falling, and whether lower BP has a greater effect on concern about falling in older and more functionally impaired individuals. Secondary analysis involving cross-sectional study of baseline characteristics of participants enrolled in the Systolic Blood Pressure Intervention Trial (SPRINT). Approximately 100 outpatient sites. SPRINT enrollees aged 50 and older (mean age 69) diagnosed with hypertension (N = 2,299). Concern about falling was determined using the shortened version of the Falls Efficacy Scale International as measured at the baseline examination. Mild concern about falling was present in 29.3% of participants and moderate to severe concern in 17.9%. Neither low BP (systolic BPconcern about falling (P > .10). Participants with moderate to severe concern about falling were taking significantly more antihypertensive medications than those with mild or no concern. After adjusting for baseline characteristics, no associations were evident between BP, medications, and concern about falling. Results were similar in older and younger participants; interactions between BP and age and functional status were not significantly associated with concern about falling. Although concern about falling is common in older adults with hypertension, it was not found to be associated with low BP or use of more antihypertensive medications in baseline data from SPRINT. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.

EFFECT OF MITRAL REGURGITATION ON CHRONIC HEART FAILURE COURSE AND STRUCTURE-FUNCTIONAL HEART STATE

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V. N. Larina

2009-01-01

Full Text Available Aim. To evaluate chronic heart failure (CHF course, functional and structural heart changes in patients with functional mitral regurgitation (MR of various degrees.Material and methods. A total of 104 outpatients (60-85 y. o. with CHF of functional class II-IV by NYHA and functional MR of I-II degrees and MR of III-IV degrees were included into the study groups.Results: Patients in both groups were comparable in sex, age, CHF duration, body mass index, systolic and diastolic blood pressure, clinical state by the clinical state scale, quality of life, anxious and depressive status. The majority of patients with MR III had significant left ventricle (LV systolic dysfunction (p=0,029, severe CHF course (p=0,034, received furosemide (p=0.004 and digoxin (p=0,004. They had significant increase in end-diastolic dimension (p<0,001, end-systolic dimension (p<0,001, left atrium (p=0,004, end-diastolic volume (p<0,001, end-systolic volume (p<0,001, pulmonary artery pressure (p<0,001, decrease in LV relative wall thickness (p=0,021 and LV ejection fraction (p<0,001. Patients of this group were hospitalized because of CHF decompensation and ischemic heart disease exacerbation more often (p=0,045.Conclusion. MR can be considered as one of sensitive predictors of LV geometry and function alteration in CHF patients and play an important role in symptoms development.

EFFECT OF MITRAL REGURGITATION ON CHRONIC HEART FAILURE COURSE AND STRUCTURE-FUNCTIONAL HEART STATE

Directory of Open Access Journals (Sweden)

V. N. Larina

2016-01-01

Full Text Available Aim. To evaluate chronic heart failure (CHF course, functional and structural heart changes in patients with functional mitral regurgitation (MR of various degrees.Material and methods. A total of 104 outpatients (60-85 y. o. with CHF of functional class II-IV by NYHA and functional MR of I-II degrees and MR of III-IV degrees were included into the study groups.Results: Patients in both groups were comparable in sex, age, CHF duration, body mass index, systolic and diastolic blood pressure, clinical state by the clinical state scale, quality of life, anxious and depressive status. The majority of patients with MR III had significant left ventricle (LV systolic dysfunction (p=0,029, severe CHF course (p=0,034, received furosemide (p=0.004 and digoxin (p=0,004. They had significant increase in end-diastolic dimension (p<0,001, end-systolic dimension (p<0,001, left atrium (p=0,004, end-diastolic volume (p<0,001, end-systolic volume (p<0,001, pulmonary artery pressure (p<0,001, decrease in LV relative wall thickness (p=0,021 and LV ejection fraction (p<0,001. Patients of this group were hospitalized because of CHF decompensation and ischemic heart disease exacerbation more often (p=0,045.Conclusion. MR can be considered as one of sensitive predictors of LV geometry and function alteration in CHF patients and play an important role in symptoms development.

Decrease in coronary vascular volume in systole augments cardiac contraction.

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Willemsen, M J; Duncker, D J; Krams, R; Dijkman, M A; Lamberts, R R; Sipkema, P; Westerhof, N

2001-08-01

Coronary arterial inflow is impeded and venous outflow is increased as a result of the decrease in coronary vascular volume due to cardiac contraction. We evaluated whether cardiac contraction is influenced by interfering with the changes of the coronary vascular volume over the heart cycle. Length-tension relationships were determined in Tyrode-perfused rat papillary muscle and when coronary vascular volume changes were partly inhibited by filling it with congealed gelatin or perfusing it with a high viscosity dextran buffer. Also, myocyte thickening during contraction was reduced by placing a silicon tube around the muscle. Increasing perfusion pressure from 8 to 80 cmH2O, increased developed tension by approximately 40%. When compared with the low perfusion state, developed tension of the gelatin-filled vasculature was reduced to 43 +/- 6% at the muscle length where the muscle generates the largest developed tension (n = 5, means +/- SE). Dextran reduced developed tension to 73 +/- 6% (n = 6). The silicon tube, in low perfusion state, reduced the developed tension to 83 +/- 7% (n = 4) of control. Time-control and oxygen-lowering experiments show that the findings are based on mechanical effects. Thus interventions to prevent myocyte thickening reduce developed tension. We hypothesize that when myocyte thickening is prevented, intracellular pressure increases and counteracts the force produced by the contractile apparatus. We conclude that emptying of the coronary vasculature serves a physiological purpose by facilitating cardiomyocyte thickening thereby augmenting force development.

Application of Real-Time Three-Dimensional Echocardiography to Evaluate the Pre- and Postoperative Right Ventricular Systolic Function of Patients with Tetralogy of Fallot

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Cui, Cunying; Liu, Lin; Fan, Taibing; Peng, Bangtian; Cheng, Zhaoyun; Ge, Zhenwei; Li, Yanan; Liu, Yuanyuan; Zhang, Yanwei; Ai, Feng; Zhang, Lianzhong

2015-01-01

Tetralogy of Fallot (ToF) can be challenging for clinicians to both diagnose and treat, given the multiple heart defects that are by definition associated with the illness. This study investigates the value of real-time three- dimensional echocardiography (RT-3DE) in evaluating the pre-and postoperative right ventricular systolic function of patients with tetralogy of Fallot. A total of 41 ToF patients were divided into two groups: the child group (CG) and the adult group (AG) according to age. The right ventricular end-diastolic volume (RVEDV), right ventricular end-systolic volume (RVESV), and the right ventricular ejection fraction (RVEF) of ToF patients were measured before surgery, 7 days, and 3 months after the surgery. The correlation between the preoperative Nakata index and RVEF was then analyzed. Compared with the RVEDV and RVESV prior to surgery, those of the postoperative 7-day and 3-month were not statistically significant (p > 0.05). However, RVEF decreased, and the difference was statistically significant (p 0.05). Compared with the pre-and postoperative RVEDV and RVESV of CG, those of AG increased. However, RVEF decreased, and the differences were statistically significant (p < 0.05). Our study indicated that the correlation between preoperative Nakata index and RVEF was good. Ultimately, we did confirm that RT-3DE can quantitatively evaluate the right ventricular volume and systolic function of ToF patients, thereby providing clinical significance in determining postoperative efficacy and prognosis evaluation. PMID:27122891

6A.03: THE RELATIONSHIP BETWEEN INTER-ARM SYSTOLIC BLOOD PRESSURE AND CARDIOVASCULAR RISK FACTORS.

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Ma, W; Zhang, B; Yang, Y; Qi, L; Meng, L; Zhang, Y; Huo, Y

2015-06-01

To analyze the relationship between the inter arm blood pressure difference (IASBPD) and other cardiovascular risk factors. To identify what factors are associated with this difference in a general population. The study subjects were 1426 individuals. The BP was measured simultaneously in both arms by VP1000 vascular profiler (Omron Colin, Japan). The inter-arm BP difference was expressed as the absolute difference (|R - L|). The various risk factors, ba-PWV, carotid IMT and plaque were compared between IASBPD more than 10mmHg group and IASBPD less than 10mmHg group. The relationship between IASBPD more than 10mmHg and various cardiovascular risk factors were analyzed by multivariate logistic analysis. Left upper limb systolic blood pressure was higher than the right upper limb, while right upper limb diastolic pressure was higher than the left upper limb. The prevalence of hypertension was higher in IASBPD increasing group than normal group (40.5% vs 22.6%, p blood pressure were also higher in IASBPD increasing group(p blood pressure, BMI and ABI independently, which may partly explain the mechanism that increasing IASBPD is associated with cardiovascular disease.

2014 Hypertension Guideline: Recommendation for a Change in Goal Systolic Blood Pressure

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Handler, Joel

2015-01-01

The 2014 Kaiser Permanente Care Management Institute National Hypertension Guideline was developed to assist primary care physicians and other health care professionals in the outpatient treatment of uncomplicated hypertension in adult men and nonpregnant women aged 18 years and older. The new guideline reflects general acceptance, with minor modifications, of the “Evidence-Based Guideline” report by the panel members appointed to the National Heart, Lung, and Blood Institute 8th Joint National Committee. A major practice change is the recommendation for goal systolic blood pressure less than 150 mmHg in patients aged 60 years and older who are treated for hypertension in the absence of diabetes or chronic kidney disease. This article describes the reasons for, evidence for, and consequences of the change, and is followed by the National Guidelines handout. PMID:26057683

Hyperglycemia and nocturnal systolic blood pressure are associatedwith left ventricular hypertrophy and diastolic dysfunction in hypertensive diabetic patients

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Felício João S

2006-09-01

Full Text Available Abstract Background The aim of this study was to determine if hypertensive type 2 diabetic patients, when compared to patients with essential hypertension have an increased left ventricular mass index (LVMI and a worse diastolic function, and if this fact would be related to 24-h pressoric levels changes. Methods Ninety-one hypertensive patients with type 2 diabetes mellitus (DM (group-1 [G1], 59 essential hypertensive patients (group-2 [G2] and 26 healthy controls (group-3 [G3] were submitted to 24-h Ambulatory Blood Pressure Monitoring (ABPM and echocardiography (ECHO with Doppler. We calculated an average of fasting blood glucose (AFBG values of G1 from the previous 4.2 years and a glycemic control index (GCI (percentual of FBG above 200 mg/dl. Results G1 and G2 did not differ on average of diurnal systolic and diastolic BP. However, G1 presented worse diastolic function and a higher average of nocturnal systolic BP (NSBP and LVMI (NSBP = 132 ± 18 vs 124 ± 14 mmHg; P 2; P 165 mg/dl showed an additional risk of LVH (P Conclusion This study suggests that hyperglycemia and higher NSBP levels should be responsible for an increased prevalence of LVH in hypertensive patients with Type 2 DM.

The effect of different volumes of acute resistance exercise on elderly individuals with treated hypertension.

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Scher, Luria M L; Ferriolli, Eduardo; Moriguti, Julio C; Scher, Ricardo; Lima, Nereida K C

2011-04-01

Acute resistance exercise can reduce the blood pressure (BP) of hypertensive subjects. The aim of this study was to evaluate the effect of different volumes of acute low-intensity resistance exercise over the magnitude and the extent of BP changes in treated hypertensive elderly individuals. Sixteen participants (7 men, 9 women), with mean age of 68 ± 5 years, performed 3 independent randomized sessions: Control (C: 40 minutes of rest), Exercise 1 (E1: 20 minutes, 1 lap in the circuit), and Exercise 2 (E2: 40 minutes, 2 laps in the circuit) with the intensity of 40% of 1 repetition maximum. Blood pressure was measured before (during 20 minutes) and after each session (every 5 minutes during 60 minutes) using both a mercury sphygmomanometer and a semiautomatic device (Omrom-HEM-431). After that, 24-hour ambulatory blood pressure monitoring was performed (Dyna-MAPA). Blood pressure decreased during the first 60 minutes (systolic: p exercise sessions. Only the highest volume session promoted a reduction of mean systolic 24-hour BP and awake BP (p exercise, with higher diastolic BP during sleep (p exercise sessions in a circuit with different volumes reduced BP during the first 60 minutes after exercise in elderly individuals with treated hypertension. However, only the highest volume promoted a reduction of mean 24-hour and awake systolic BP.

Intrinsic positive end-expiratory pressure during one-lung ventilation of patients with pulmonary hyperinflation. Influence of low respiratory rate with unchanged minute volume.

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Szegedi, L L; Barvais, L; Sokolow, Y; Yernault, J C; d'Hollander, A A

2002-01-01

We measured lung mechanics and gas exchange during one-lung ventilation (OLV) of patients with chronic obstructive pulmonary disease, using three respiratory rates (RR) and unchanged minute volume. We studied 15 patients about to undergo lung surgery, during anaesthesia, and placed in the lateral position. Ventilation was with constant minute volume, inspiratory flow and FIO2. For periods of 15 min, RR of 5, 10, and 15 bpm were applied in a random sequence and recordings were made of lung mechanics and an arterial blood gas sample was taken. Data were analysed with the repeated measures ANOVA and paired t-test with Bonferroni correction. PaO2 changes were not significant. At the lowest RR, PaCO2 decreased (from 42 (SD 4) mm Hg at RR 15-41 (4) mm Hg at RR 10 and 39 (4) mm Hg at RR 5, P<0.01), and end-tidal carbon dioxide increased (from 33 (5) mm Hg at RR 15 to 35 (5) mm Hg at RR 10 and 36 (6) mm Hg at RR 5, P<0.01). Intrinsic positive end-expiratory pressure (PEEPi) was reduced even with larger tidal volumes (from 6 (4) cm H2O at RR 15-5 (4) cm H2O at RR 10, and 3 (3) cm H2O at RR 5, P<0.01), most probably caused by increased expiratory time at the lowest RR. A reduction in RR reduces PEEPi and hypercapnia during OLV in anaesthetized patients with chronic obstructive lung disease.

A new methodological approach to assess cardiac work by pressure-volume and stress-length relations in patients with aortic valve stenosis and dilated cardiomyopathy.

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Alter, P; Rupp, H; Rominger, M B; Klose, K J; Maisch, B

2008-01-01

In experimental animals, cardiac work is derived from pressure-volume area and analyzed further using stress-length relations. Lack of methods for determining accurately myocardial mass has until now prevented the use of stress-length relations in patients. We hypothesized, therefore, that not only pressure-volume loops but also stress-length diagrams can be derived from cardiac volume and cardiac mass as assessed by cardiac magnetic resonance imaging (CMR) and invasively measured pressure. Left ventricular (LV) volume and myocardial mass were assessed in seven patients with aortic valve stenosis (AS), eight with dilated cardiomyopathy (DCM), and eight controls using electrocardiogram (ECG)-gated CMR. LV pressure was measured invasively. Pressure-volume curves were calculated based on ECG triggering. Stroke work was assessed as area within the pressure-volume loop. LV wall stress was calculated using a thick-wall sphere model. Similarly, stress-length loops were calculated to quantify stress-length-based work. Taking the LV geometry into account, the normalization with regard to ventricular circumference resulted in "myocardial work." Patients with AS (valve area 0.73+/-0.18 cm(2)) exhibited an increased LV myocardial mass when compared with controls (Pwork of AS was unchanged when compared with controls (0.539+/-0.272 vs 0.621+/-0.138 Nm, not significant), whereas DCM exhibited a significant depression (0.367+/-0.157 Nm, Pwork was significantly reduced in both AS and DCM when compared with controls (129.8+/-69.6, 200.6+/-80.1, 332.2+/-89.6 Nm/m(2), Pmethodological approach of using CMR and invasive pressure measurement. Myocardial work was reduced in patients with DCM and noteworthy also in AS, while stroke work was reduced in DCM only. Most likely, deterioration of myocardial work is crucial for the prognosis. It is suggested to include these basic physiological procedures in the clinical assessment of the pump function of the heart.

Non-constrained monitoring of systolic blood pressure on a weighing scale

International Nuclear Information System (INIS)

Shin, Jae Hyuk; Lee, Kang Moo; Park, Kwang Suk

2009-01-01

In this study, we developed a novel technique for estimating non-constrained and cuffless blood pressure (BP) that was based on electrocardiogram (ECG) and ballistocardiogram (BCG). The BCG was non-invasively measured using a common electronic weighing scale when a subject was standing on it. The ECG was measured using three different methods: on the chest using Ag/AgCl electrodes, on the hands using dry electrodes and on the feet also using dry electrodes. For a BP correlated parameter, a time interval parameter, which was defined as the time difference between the ECG R-peak and BCG J-peak, was employed for evaluating and estimating beat-to-beat BP. Under a BP varying experiment with a Valsalva manoeuvre, the R–J intervals were extracted at every beat cycle and a systolic blood pressure (SBP) estimation equation was established using linear regression analysis for each subject. In the case of feet delivered ECG (F-ECG), an ensemble average technique synchronized at the BCG J-peak point was applied to extract the ECG signal from the feet. The performance of the proposed method was evaluated using Finapres, a non-invasive blood pressure measurement system, as a reference BP signal, and a scatter plot was used to find the regression line between the reference values and estimated BPs. A moving-window averaging technique was applied to remove the high-frequency noise in the R–J intervals and was applied to enhance the accuracy of the SBP estimation. For all individuals, the estimated SBP was similar to the measured SBP with a reliable correlation, which makes the proposed method suitable for use in a home healthcare system to monitor blood pressure on a weighing scale at the same time as measuring weight

Desmin loss and mitochondrial damage precede left ventricular systolic failure in volume overload heart failure.

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Guichard, Jason L; Rogowski, Michael; Agnetti, Giulio; Fu, Lianwu; Powell, Pamela; Wei, Chih-Chang; Collawn, James; Dell'Italia, Louis J

2017-07-01

Heart failure due to chronic volume overload (VO) in rats and humans is characterized by disorganization of the cardiomyocyte desmin/mitochondrial network. Here, we tested the hypothesis that desmin breakdown is an early and continuous process throughout VO. Male Sprague-Dawley rats had aortocaval fistula (ACF) or sham surgery and were examined 24 h and 4 and 12 wk later. Desmin/mitochondrial ultrastructure was examined by transmission electron microscopy (TEM) and immunohistochemistry (IHC). Protein and kinome analysis were performed in isolated cardiomyocytes, and desmin cleavage was assessed by mass spectrometry in left ventricular (LV) tissue. Echocardiography demonstrated a 40% decrease in the LV mass-to-volume ratio with spherical remodeling at 4 wk with ACF and LV systolic dysfunction at 12 wk. Starting at 24 h and continuing to 4 and 12 wk, with ACF there is TEM evidence of extensive mitochondrial clustering, IHC evidence of disorganization associated with desmin breakdown, and desmin protein cleavage verified by Western blot analysis and mass spectrometry. IHC results revealed that ACF cardiomyocytes at 4 and 12 wk had perinuclear translocation of αB-crystallin from the Z disk with increased α, β-unsaturated aldehyde 4-hydroxynonelal. Use of protein markers with verification by TUNEL staining and kinome analysis revealed an absence of cardiomyocyte apoptosis at 4 and 12 wk of ACF. Significant increases in protein indicators of mitophagy were countered by a sixfold increase in p62/sequestosome-1, which is indicative of an inability to complete autophagy. An early and continuous disruption of the desmin/mitochondrial architecture, accompanied by oxidative stress and inhibition of apoptosis and mitophagy, suggests its causal role in LV dilatation and systolic dysfunction in VO. NEW & NOTEWORTHY This study provides new evidence of early onset (24 h) and continuous (4-12 wk) desmin misarrangement and disruption of the normal sarcomeric and mitochondrial

Closing the loop: modelling of heart failure progression from health to end-stage using a meta-analysis of left ventricular pressure-volume loops.

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Warriner, David R; Brown, Alistair G; Varma, Susheel; Sheridan, Paul J; Lawford, Patricia; Hose, David R; Al-Mohammad, Abdallah; Shi, Yubing

2014-01-01

The American Heart Association (AHA)/American College of Cardiology (ACC) guidelines for the classification of heart failure (HF) are descriptive but lack precise and objective measures which would assist in categorising such patients. Our aim was two fold, firstly to demonstrate quantitatively the progression of HF through each stage using a meta-analysis of existing left ventricular (LV) pressure-volume (PV) loop data and secondly use the LV PV loop data to create stage specific HF models. A literature search yielded 31 papers with PV data, representing over 200 patients in different stages of HF. The raw pressure and volume data were extracted from the papers using a digitising software package and the means were calculated. The data demonstrated that, as HF progressed, stroke volume (SV), ejection fraction (EF%) decreased while LV volumes increased. A 2-element lumped parameter model was employed to model the mean loops and the error was calculated between the loops, demonstrating close fit between the loops. The only parameter that was consistently and statistically different across all the stages was the elastance (Emax). For the first time, the authors have created a visual and quantitative representation of the AHA/ACC stages of LVSD-HF, from normal to end-stage. The study demonstrates that robust, load-independent and reproducible parameters, such as elastance, can be used to categorise and model HF, complementing the existing classification. The modelled PV loops establish previously unknown physiological parameters for each AHA/ACC stage of LVSD-HF, such as LV elastance and highlight that it this parameter alone, in lumped parameter models, that determines the severity of HF. Such information will enable cardiovascular modellers with an interest in HF, to create more accurate models of the heart as it fails.

Closing the loop: modelling of heart failure progression from health to end-stage using a meta-analysis of left ventricular pressure-volume loops.

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David R Warriner

Full Text Available INTRODUCTION: The American Heart Association (AHA/American College of Cardiology (ACC guidelines for the classification of heart failure (HF are descriptive but lack precise and objective measures which would assist in categorising such patients. Our aim was two fold, firstly to demonstrate quantitatively the progression of HF through each stage using a meta-analysis of existing left ventricular (LV pressure-volume (PV loop data and secondly use the LV PV loop data to create stage specific HF models. METHODS AND RESULTS: A literature search yielded 31 papers with PV data, representing over 200 patients in different stages of HF. The raw pressure and volume data were extracted from the papers using a digitising software package and the means were calculated. The data demonstrated that, as HF progressed, stroke volume (SV, ejection fraction (EF% decreased while LV volumes increased. A 2-element lumped parameter model was employed to model the mean loops and the error was calculated between the loops, demonstrating close fit between the loops. The only parameter that was consistently and statistically different across all the stages was the elastance (Emax. CONCLUSIONS: For the first time, the authors have created a visual and quantitative representation of the AHA/ACC stages of LVSD-HF, from normal to end-stage. The study demonstrates that robust, load-independent and reproducible parameters, such as elastance, can be used to categorise and model HF, complementing the existing classification. The modelled PV loops establish previously unknown physiological parameters for each AHA/ACC stage of LVSD-HF, such as LV elastance and highlight that it this parameter alone, in lumped parameter models, that determines the severity of HF. Such information will enable cardiovascular modellers with an interest in HF, to create more accurate models of the heart as it fails.

Computer model analysis of the radial artery pressure waveform.

Science.gov (United States)

Schwid, H A; Taylor, L A; Smith, N T

1987-10-01

Simultaneous measurements of aortic and radial artery pressures are reviewed, and a model of the cardiovascular system is presented. The model is based on resonant networks for the aorta and axillo-brachial-radial arterial system. The model chosen is a simple one, in order to make interpretation of the observed relationships clear. Despite its simplicity, the model produces realistic aortic and radial artery pressure waveforms. It demonstrates that the resonant properties of the arterial wall significantly alter the pressure waveform as it is propagated from the aorta to the radial artery. Although the mean and end-diastolic radial pressures are usually accurate estimates of the corresponding aortic pressures, the systolic pressure at the radial artery is often much higher than that of the aorta due to overshoot caused by the resonant behavior of the radial artery. The radial artery dicrotic notch is predominantly dependent on the axillo-brachial-radial arterial wall properties, rather than on the aortic valve or peripheral resistance. Hence the use of the radial artery dicrotic notch as an estimate of end systole is unreliable. The rate of systolic upstroke, dP/dt, of the radial artery waveform is a function of many factors, making it difficult to interpret. The radial artery waveform usually provides accurate estimates for mean and diastolic aortic pressures; for all other measurements it is an inadequate substitute for the aortic pressure waveform. In the presence of low forearm peripheral resistance the mean radial artery pressure may significantly underestimate the mean aortic pressure, as explained by a voltage divider model.

Effect of high and low ultrafiltration volume during hemodialysis on relative blood volume

NARCIS (Netherlands)

Dasselaar, JJ; de Jong, PE; Huisman, RM; Franssen, CFM

2006-01-01

Achieving an optimal posthemodialysis hydration status may be difficult because objective criteria for dry weight are lacking. Both relative blood volume changes (Delta RBV) at the end of hemodialysis and Delta RBV normalized for ultrafiltration volume (Delta RBV/UF ratio) have been reported to

Combination of Glasgow Coma Scale, Age, and Systolic Blood Pressure in Assessing Patients’ Outcomes with Decreased Consciousness

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Amir S Madjid

2017-04-01

Full Text Available Glasgow Coma Scale (GCS is commonly used to assess outcomes of patients with loss of consciousness, but it is insufficient in predicting the outcome of some cases. This study aimed to assess the combination of GCS, systolic blood pressure and age to predict the outcome of patients with decreased consciousness. This was a retrospective cohort observational study of 76 loss of consciousness patients that comes into the Emergency Department of Dr. Cipto Mangunkusumo General Hospital in June-August 2014. Data was obtained from the medical records . GCS, systolic blood pressure and age were recorded when patients were admitted to the triage. Outcome was assessed two weeks after admission in the emergency department. Bivariate analysis on the GCS and age showed significant different between patients with poor outcome group with good outcome group (p<0.05 and no significant different of the systolic blood pressure between both groups (p>0.05. Multivariate analysis on the GCS and age showed good probability equation based on the calibration test and discrimination. The combination of Glasgow Coma Scale and age was accurate in assessing the outcomes of patients with loss of consciousness. Keywords. Glasgow Coma Scale, systolic, age, outcomes     Gabungan Glasgow Coma Scale, Umur, dan Tekanan Darah Sistolik Sebagai Penilai Luaran Pasien Penurunan Kesadaran   Abstrak Glasgow Coma Scale (GCS telah menjadi salah satu penilaian yang digunakan untuk menilai luaran pasien penurunan kesadaran, tetapi dinilai masih belum mampu memprediksi luaran yang terjadi. Penelitian ini bertujuan untuk menilai gabungan GCS, tekanan darah sistolik dan umur untuk memprediksi luaran pasien dengan penurunan kesadaran. Penelitian ini merupakan studi observasional kohort retrospektif yang melibatkan 76 pasien dengan penurunan kesadaran yang datang ke IGD RSUPN Dr. Cipto Mangunkusumo selama bulan Juni-Agustus 2014. Data diambil dari rekam medik. GCS, tekanan darah sistolik dan

Load dependency in force-length relations in isolated single cardiomyocytes.

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Iribe, Gentaro; Kaneko, Toshiyuki; Yamaguchi, Yohei; Naruse, Keiji

2014-08-01

The previously reported pressure-volume (PV) relationship in frog hearts shows that end-systolic PV relation (ESPVR) is load dependent, whereas ESPVR in canine hearts is load independent. To study intrinsic cardiac mechanics in detail, it is desirable to study mechanics in a single isolated cardiomyocyte that is free from interstitial connective tissue. Previous single cell mechanics studies used a pair of carbon fibers (CF) attached to the upper surface of opposite cell ends to stretch cells. These studies showed that end-systolic force-length (FL) relation (ESFLR) is load independent. However, the range of applicable mechanical load using the conventional technique is limited because of weak cell-CF attachment. Therefore, the behavior of ESFLR in single cells under physiologically possible conditions of greater load is not yet well known. To cover wider loading range, we contrived a new method to hold cell-ends more firmly using two pairs of CF attached to both upper and bottom surfaces of cells. The new method allowed stretching cells to 2.2 μm or more in end-diastolic sarcomere length. ESFLR virtually behaves in a load independent manner only with end-diastolic sarcomere length less than 1.95 μm. It exhibited clear load dependency with higher preload, especially with low afterload conditions. Instantaneous cellular elastance curves showed that decreasing afterload enhanced relaxation and slowed time to peak elastance, as previously reported. A simulation study of a mathematical model with detailed description of thin filament activation suggested that velocity dependent thin filament inactivation is crucial for the observed load dependent behaviors and previously reported afterload dependent change in Ca(2+) transient shape. Copyright © 2014 Elsevier Ltd. All rights reserved.

Traditional systolic blood pressure targets underestimate hypotension-induced secondary brain injury.

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Brenner, Megan; Stein, Deborah M; Hu, Peter F; Aarabi, Bizhan; Sheth, Kevin; Scalea, Thomas M

2012-05-01

Vital signs, particularly blood pressure, are often manipulated to maximize perfusion and optimize recovery from severe traumatic brain injury (sTBI). We investigated the utility of automated continuously recorded vital signs to predict outcomes after sTBI. Sixty patients with head Abbreviated Injury Scale score ≥ 3, age >14 years, "isolated" TBI, and need for intracranial pressure monitoring were prospectively enrolled at a single, large urban tertiary care facility. Outcome was measured by mortality and extended Glasgow Outcome Scale (GOSE) at 12 months. Continuous, automated, digital data were collected every 6 seconds for 72 hours after admission, and 5-minute means of systolic blood pressure (SBP) were recorded. We calculated SBP as pressure × time dose (PTD) to describe the cumulative amplitude and duration of episodes above and below clinical thresholds. The extent and duration of the insults were calculated as percent time (%time), PTD, and PTD per day (PTD/D) of defined thresholds (SBP: 100 bpm and >120 bpm; and SpO(2): GOSE by receiver operator characteristics. Mean age was 33.9 (range, 16-83) years, mean admission Glasgow Coma Scale score 6.4 ± 3, and mean head Abbreviated Injury Scale score 4.2 ± 0.72. The 30-day mortality rate was 13.3%. Of the 45 patients in whom GOSE at 12 months was available, 28 (62%) had good neurologic outcomes (GOSE score >4). Traditional markers of poor outcome (admission SBP, admission Glasgow Coma Scale, and Marshall score) were not different between groups with good or poor outcome. PTD, PTD/D, and %time SBP GOSE (p = 0.02). PTD/D SBP GOSE (p < 0.05). Within the first 48 hours of intensive care unit admission, hypotension was found to be predictive of mortality and functional outcomes at higher thresholds than traditionally defined. Systemic blood pressure targets closer to 120 mm Hg may be more efficacious in minimizing secondary insults and particularly useful in settings without invasive intracranial monitoring

Mechanical energy yields and pressure volume and pressure time curves for whole core fuel-coolant interactions

Energy Technology Data Exchange (ETDEWEB)

Coddington, P [United Kingdom Atomic Energy Authority, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

1979-10-15

In determining the damage consequences of a whole core Fuel-Coolant Interaction (FCI), one measure of the strength of a FCI that can be used and is independent of the system geometry is the constant volume mixing mechanical yield (often referred to as the Hicks-Menzies yield), which represents a near upper limit to the mechanical work of a FCI. This paper presents a recalculation of the Hicks-Menzies yields for UO{sub 2} and sodium for a range of initial fuel temperatures and fuel to coolant mass ratios, using recently published UO{sub 2} and sodium equation of state data. The work presented here takes a small number of postulated FCIs with as wide range as possible of thermal interaction parameters and determines their pressure-volume P(V) and pressure-time P(t) relations, using geometrical constraints representative of the reactor. Then by examining these P(V) and P(t) curves a representative pressure-relative volume curve or range of possible curves, for use in containment analysis, is recommended

Measurement of right ventricular volumes using 131I-MAA

International Nuclear Information System (INIS)

Sekimoto, T.; Grover, R.F.

1975-01-01

A method is presented for determining the right ventricular residual ratio, that is, the ratio of the end-systolic volume to the end-diastolic volume during each cardiac cycle. 131 I-MAA was injected as a bolus into the right ventricle, and the ratio of isotope remaining in the chamber during the succeeding cardiac cycles was determined with a collimated scintillation counter placed over the right ventricle. Since the counter detected the radioactivity from the entire right ventricular cavity, potential errors from incomplete mixing were minimized. The washout curve from the ventricle was distorted somewhat by the accumulation of isotope in intervening lung tissue. This distortion was eliminated by subtracting the build-up curve of radioactivity in the lung recorded simultaneously with a second scintillation counter positioned over the lateral chest wall. In 14 dogs anesthetized with chloralose, the right ventricular residual ratio was relatively constant at 40.4 +- 3.1 per cent. Duplicate measurements differed by less than 3 percent indicating the good reproducibility of the method. Right ventricular stroke volume was determined from cardiac output (dye dilution) and heart rate. With this and the simultaneously determined residual ratio ( 131 I-MAA), end-diastolic volume could be calculated. Stroke volume and stroke work were highly correlated with end-diastolic volume, in keeping with the Frank-Starling mechanism. (U.S.)

Effect of self-monitoring and medication self-titration on systolic blood pressure in hypertensive patients at high risk of cardiovascular disease: the TASMIN-SR randomized clinical trial.

Science.gov (United States)

McManus, Richard J; Mant, Jonathan; Haque, M Sayeed; Bray, Emma P; Bryan, Stirling; Greenfield, Sheila M; Jones, Miren I; Jowett, Sue; Little, Paul; Penaloza, Cristina; Schwartz, Claire; Shackleford, Helen; Shovelton, Claire; Varghese, Jinu; Williams, Bryan; Hobbs, F D Richard; Gooding, Trevor; Morrey, Ian; Fisher, Crispin; Buckley, David

2014-08-27

Self-monitoring of blood pressure with self-titration of antihypertensives (self-management) results in lower blood pressure in patients with hypertension, but there are no data about patients in high-risk groups. To determine the effect of self-monitoring with self-titration of antihypertensive medication compared with usual care on systolic blood pressure among patients with cardiovascular disease, diabetes, or chronic kidney disease. A primary care, unblinded, randomized clinical trial involving 552 patients who were aged at least 35 years with a history of stroke, coronary heart disease, diabetes, or chronic kidney disease and with baseline blood pressure of at least 130/80 mm Hg being treated at 59 UK primary care practices was conducted between March 2011 and January 2013. Self-monitoring of blood pressure combined with an individualized self-titration algorithm. During the study period, the office visit blood pressure measurement target was 130/80 mm Hg and the home measurement target was 120/75 mm Hg. Control patients received usual care consisting of seeing their health care clinician for routine blood pressure measurement and adjustment of medication if necessary. The primary outcome was the difference in systolic blood pressure between intervention and control groups at the 12-month office visit. Primary outcome data were available from 450 patients (81%). The mean baseline blood pressure was 143.1/80.5 mm Hg in the intervention group and 143.6/79.5 mm Hg in the control group. After 12 months, the mean blood pressure had decreased to 128.2/73.8 mm Hg in the intervention group and to 137.8/76.3 mm Hg in the control group, a difference of 9.2 mm Hg (95% CI, 5.7-12.7) in systolic and 3.4 mm Hg (95% CI, 1.8-5.0) in diastolic blood pressure following correction for baseline blood pressure. Multiple imputation for missing values gave similar results: the mean baseline was 143.5/80.2 mm Hg in the intervention group vs 144.2/79.9 mm Hg in the control group, and

Hypertension. Age-specificity of blood-pressure-associated complications

OpenAIRE

Staessen, Jan A

2014-01-01

In an analysis of electronic health records, 1.25 million patients aged ≥30 years without diagnosed cardiovascular disease experienced 83,098 cardiovascular events during follow-up (median 5.2 years). Associations between incident cardiovascular disease and blood pressure differed for systolic and diastolic blood pressures and between the 12 cardiovascular end points examined.

Thermodynamic relations in high temperature and high pressure physics of solids

International Nuclear Information System (INIS)

Kumar, Munish

1998-01-01

Various possible simple relations based on the exact and approximate thermodynamic relations are derived. These relations can be used to investigate the variation of unit cell volume under the effect of pressure and temperature. Thermal expansivity and compressibility can be investigated directly at any pressure or temperature, or through the knowledge of equation of state (EOS). A relation to determine Anderson-Grueneisen parameter δ T under the effect of pressure is predicted. It is discussed that δ T is independent of pressure and thus Murnaghan equation of state works well in low pressure ranges, while the variation of δ T under high pressure should be taken into account. The product of coefficient of volume thermal expansion and bulk modulus remains constant, is correct at high pressure, provided that the pressure dependence of δ T is considered. (author)

Bulk-volume behavior of pressure-densified amorphous polymers and free-volume behavior by positron annihilation lifetime measurement

International Nuclear Information System (INIS)

Hagiwara, K.; Ougizawa, T.; Inoue, T.; Hirata, K.; Kobayashi, Y.

2001-01-01

In order to study the nature of amorphous polymers, the free volume contribution on the bulk volume change was investigated on the basis of the relationship between the bulk volume behavior by PVT (pressure-volume-temperature) measurement and the free volume behavior by PALS (positron annihilation lifetime spectroscopy) measurement. A densified glass, prepared by cooling at constant rate from the melt state temperature to room temperature under 200 MPa, showed smaller bulk volume and free volume than non-densified glass. And the densified glass showed not only the same glass transition temperature (Tg) as non-densified glass but also another transition at lower temperature around (Tg-30 C). In this glass-glass transition, both the bulk volume and free volume of densified glass recovered to those of non-densified glass. Moreover the densified glass showed different thermal behavior from the glass which was enthalpy-relaxed under atmospheric pressure. From those results, it was considered that the free volume behavior largely related to the behavior of amorphous polymers. (orig.)

Significance of white-coat hypertension in older persons with isolated systolic hypertension

DEFF Research Database (Denmark)

Franklin, Stanley S; Thijs, Lutgarde; Hansen, Tine W

2012-01-01

The significance of white-coat hypertension in older persons with isolated systolic hypertension remains poorly understood. We analyzed subjects from the population-based 11-country International Database on Ambulatory Blood Pressure Monitoring in Relation to Cardiovascular Outcomes database who ...... had daytime ambulatory blood pressure (BP; ABP) and conventional BP (CBP) measurements. After excluding persons with diastolic hypertension by CBP (=90 mm Hg) or by daytime ABP (=85 mm Hg), a history of cardiovascular disease, and persons...

Synergistic Utility of Brain Natriuretic Peptide and Left Ventricular Global Longitudinal Strain in Asymptomatic Patients With Significant Primary Mitral Regurgitation and Preserved Systolic Function Undergoing Mitral Valve Surgery.

Science.gov (United States)

Alashi, Alaa; Mentias, Amgad; Patel, Krishna; Gillinov, A Marc; Sabik, Joseph F; Popović, Zoran B; Mihaljevic, Tomislav; Suri, Rakesh M; Rodriguez, L Leonardo; Svensson, Lars G; Griffin, Brian P; Desai, Milind Y

2016-07-01

In asymptomatic patients with ≥3+ mitral regurgitation and preserved left ventricular (LV) ejection fraction who underwent mitral valve surgery, we sought to discover whether baseline LV global longitudinal strain (LV-GLS) and brain natriuretic peptide provided incremental prognostic utility. Four hundred and forty-eight asymptomatic patients (61±12 years and 69% men) with ≥3+ primary mitral regurgitation and preserved left ventricular ejection fraction, who underwent mitral valve surgery (92% repair) at our center between 2005 and 2008, were studied. Baseline clinical and echocardiographic data (including LV-GLS using Velocity Vector Imaging, Siemens, PA) were recorded. The Society of Thoracic Surgeons score was calculated. The primary outcome was death. Mean Society of Thoracic Surgeons score, left ventricular ejection fraction, mitral effective regurgitant orifice, indexed LV end-diastolic volume, and right ventricular systolic pressure were 4±1%, 62±3%, 0.55±0.2 cm(2), 58±13 cc/m(2), and 37±15 mm Hg, respectively. Forty-five percent of patients had flail. Median log-transformed BNP and LV-GLS were 4.04 (absolute brain natriuretic peptide: 60 pg/dL) and -20.7%. At 7.7±2 years, death occurred in 41 patients (9%; 0% at 30 days). On Cox analysis, a higher Society of Thoracic Surgeons score (hazard ratio 1.55), higher baseline right ventricular systolic pressure (hazard ratio 1.11), more abnormal LV-GLS (hazard ratio 1.17), and higher median log-transformed BNP (hazard ratio 2.26) were associated with worse longer-term survival (all Pright ventricular systolic pressure) provided incremental prognostic utility (χ(2) for longer-term mortality increased from 31-47 to 61; Pleft ventricular ejection fraction who underwent mitral valve surgery, brain natriuretic peptide and LV-GLS provided synergistic risk stratification, independent of established factors. © 2016 American Heart Association, Inc.

The effect of endogenously released glucose, insulin, glucagon-like peptide 1, ghrelin on cardiac output, heart rate, stroke volume, and blood pressure

Directory of Open Access Journals (Sweden)

Hlebowicz Joanna

2011-12-01

Full Text Available Abstract Background Ingestion of a meal increases the blood flow to the gastrointestinal organs and affects the heart rate (HR, blood pressure and cardiac output (CO, although the mechanisms are not known. The aim of this study was to evaluate the effect of endogenously released glucose, insulin, glucagon-like peptide 1 (GLP-1, ghrelin on CO, HR, stroke volume (SV, and blood pressure. Methods Eleven healthy men and twelve healthy women ((mean ± SEM aged: 26 ± 0.2 y; body mass index: 21.8 ± 0.1 kg/m2 were included in this study. The CO, HR, SV, systolic and diastolic blood pressure, antral area, gastric emptying rate, and glucose, insulin, GLP-1 and ghrelin levels were measured. Results The CO and SV at 30 min were significantly higher, and the diastolic blood pressure was significantly lower, than the fasting in both men and women (P P = 0.015, r = 0.946, and between ghrelin levels and HR (P = 0.013, r = 0.951 at 110 min. Significant correlations were also found between the change in glucose level at 30 min and the change in systolic blood pressure (P = 0.021, r = -0.681, and the change in SV (P = 0.008, r = -0.748 relative to the fasting in men. The insulin 0-30 min AUC was significantly correlated to the CO 0-30 min AUC (P = 0.002, r = 0.814 in men. Significant correlations were also found between the 0-120 min ghrelin and HR AUCs (P = 0.007, r = 0.966 in men. No statistically significant correlations were seen in women. Conclusions Physiological changes in the levels of glucose, insulin, GLP-1 and ghrelin may influence the activity of the heart and the blood pressure. There may also be gender-related differences in the haemodynamic responses to postprandial changes in hormone levels. The results of this study show that subjects should not eat immediately prior to, or during, the evaluation of cardiovascular interventions as postprandial affects may affect the results, leading to erroneous interpretation of the cardiovascular effects of the

Increased augmentation index and central systolic arterial pressure are associated with lower school and motor performance in young adolescents.

Science.gov (United States)

Vogrin, Bernarda; Slak Rupnik, Marjan; Mičetić-Turk, Dušanka

2017-12-01

Objective In adults, improper arterial function has been linked to cognitive impairment. The pulse wave velocity (PWV), augmentation index (AIx) and other vascular parameters are useful indicators of arterial health. In our study, we monitored arterial properties, body constitution, school success, and motor skills in young adolescents. We hypothesize that reduced cognitive and motor abilities have a vascular origin in children. Methods We analysed 81 healthy school children aged 11-16 years. Anthropometry central systolic arterial pressure, body mass index (BMI), standard deviation scores (SDS) BMI, general school performance grade, and eight motor tests were assessed. PWV, AIx, and central systolic arterial pressure (SBPao) were measured. Results AIx and SBPao correlated negatively with school performance grades. Extremely high AIx, PWV and SBPao values were observed in 5% of children and these children had average to low school performance. PWV correlated significantly with weight, height, and waist and hip circumference. AIx, PWV, school success, and BMI correlated strongly with certain motor functions. Conclusions Increased AIx and SBPao are associated with lower school and motor performance in children. PWV is influenced by the body's constitution.

Respiratory effects of low versus high tidal volume with or without positive end-expiratory pressure in anesthetized dogs with healthy lungs.

Science.gov (United States)

De Monte, Valentina; Bufalari, Antonello; Grasso, Salvatore; Ferrulli, Fabienne; Crovace, Alberto Maria; Lacitignola, Luca; Staffieri, Francesco

2018-05-01

OBJECTIVE To evaluate the impact of 2 tidal volumes (T V s) with or without positive end-expiratory pressure (PEEP) on lung mechanics, aeration, and gas exchange in healthy anesthetized dogs. ANIMALS 40 mixed-breed dogs with healthy lungs. PROCEDURES Anesthetized dogs were randomly assigned to 4 groups (n = 10/group) with different ventilatory settings: T V of 8 mL/kg and PEEP of 0 cm H 2 O (low T V group), T V of 8 mL/kg and PEEP of 5 cm H 2 O (low T V plus PEEP group), T V of 15 mL/kg and PEEP of 0 cm H 2 O (high T V group), or T V of 15 mL/kg and PEEP of 5 cm H 2 O (high T V plus PEEP group). Expired CO 2 and respiratory rate were titrated on the basis of a predetermined stepwise protocol. Gas exchange, respiratory mechanics, and pulmonary aeration were evaluated by means of CT 30 minutes after starting mechanical ventilation at the assigned setting. RESULTS Partial pressures of arterial and expired CO 2 were higher in the low T V and low T V plus PEEP groups than in the high T V and high T V plus PEEP groups. Peak and plateau airway pressures were higher in the PEEP group than in the other groups. Static lung compliance was higher in the high T V plus PEEP group than in the low T V group. Relative percentages of atelectatic and poorly aerated lung were lower in the high T V plus PEEP group than in the other groups. Oxygenation was similar among groups. CONCLUSIONS AND CLINICAL RELEVANCE Differences in T V and PEEP application during mechanical ventilation may affect respiratory function in anesthetized dogs with healthy lungs. Ventilation with a T V of 15 mL/kg and PEEP of 5 cm H 2 O significantly improved lung compliance and reduced the amount of atelectatic and poorly aerated lung.

Evaluation of right ventricular volumes measured by magnetic resonance imaging

DEFF Research Database (Denmark)

Møgelvang, J; Stubgaard, M; Thomsen, C

1988-01-01

stroke volume was calculated as the difference between end-diastolic and end-systolic volume and compared to left ventricular stroke volume and to stroke volume determined simultaneously by a classical indicator dilution technique. There was good agreement between right ventricular stroke volume......Right ventricular volumes were determined in 12 patients with different levels of right and left ventricular function by magnetic resonance imaging (MRI) using an ECG gated multisection technique in planes perpendicular to the diastolic position of the interventricular septum. Right ventricular...... determined by MRI and by the indicator dilution method and between right and left ventricular stroke volume determined by MRI. Thus, MRI gives reliable values not only for left ventricular volumes, but also for right ventricular volumes. By MRI it is possible to obtain volumes from both ventricles...

Effects of Propranolol on the Left Ventricular Volume of Normal Subjects During CT Coronary Angiography

International Nuclear Information System (INIS)

Mo, Yuan Heng; Jaw, Fu Shan; Wang, Yung Cheng; Jeng, Chin Ming; Peng, Shinn Forng

2011-01-01

The purpose of this study is to determine the effects of propranolol on the left ventricular (LV) volume during CT coronary angiography. The LV volume of 252 normal Chinese subjects (126 subjects with propranolol medication and 126 age- and gender-matched Chinese subjects without medication) was estimated using 64 slices multi-detector CT (MDCT). The heart rate difference was analyzed by the logistic linear regression model with variables that included gender, age, body height, body weight, systolic blood pressure (SBP), diastolic blood pressure (DBP) and the dosage of propranolol. The following global LV functional parameters were calculated: the real-end diastolic volume (EDV), the real-end systolic volume (ESV) and the real-ejection fraction (EF). The female subjects had a greater decrease of heart rate after taking propranolol. The difference of heart rate was negatively correlated with the dosage of propranolol. The real-EDV, the real-ESV and the real-EF ranged from 48.1 to 109 mL/m2, 6.1 to 57.1 mL/m2 and 41% to 88%, respectively. There was no significant difference in the SBP and DBP between the groups without and with propranolol medication (123 ± 17 and 80 ± 10 mmHg; 120 ± 14 and 80 ± 11 mmHg, respectively). The real-EDV showed no significant difference between these two groups, but the real-ESV and real-EF showed significant differences between these two groups (69.4 ± 9.3 and 70.6 ± 8.9 mL/m2; 23.5 ± 5.7 and 25.6 ± 3.7 mL/m2, 66.5 ± 5.1% and 63.5 ± 4.6%, respectively). The difference of heart rate is significantly influenced by gender and the dosage of propranolol. Propranolol will also increase the ESV, which contributes to a decreased EF, while the SBP, DBP and EDV are not statistically changed.

Association of Interarm Systolic Blood Pressure Difference with Atherosclerosis and Left Ventricular Hypertrophy

Science.gov (United States)

Su, Ho-Ming; Lin, Tsung-Hsien; Hsu, Po-Chao; Chu, Chun-Yuan; Lee, Wen-Hsien; Chen, Szu-Chia; Lee, Chee-Siong; Voon, Wen-Chol; Lai, Wen-Ter; Sheu, Sheng-Hsiung

2012-01-01

An interarm systolic blood pressure (SBP) difference of 10 mmHg or more have been associated with peripheral artery disease and adverse cardiovascular outcomes. We investigated whether an association exists between this difference and ankle-brachial index (ABI), brachial-ankle pulse wave velocity (baPWV), and echocardiographic parameters. A total of 1120 patients were included in the study. The bilateral arm blood pressures were measured simultaneously by an ABI-form device. The values of ABI and baPWV were also obtained from the same device. Clinical data, ABIdifference ≥10 mmHg were compared and analyzed. We performed two multivariate forward analyses for determining the factors associated with an interarm SBP difference ≥10 mmHg [model 1: significant variables in univariate analysis except left ventricular mass index (LVMI); model 2: significant variables in univariate analysis except ABIdifference ≥10 mmHg. Female, hypertension, and high body mass index were also associated with an interarm SBP difference ≥10 mmHg. Our study demonstrated that ABIdifference of 10 mmHg or more. Detection of an interarm SBP difference may provide a simple method of detecting patients at increased risk of atherosclerosis and left ventricular hypertrophy. PMID:22927905

Sex differences in ventricular-vascular coupling following endurance training.

Science.gov (United States)

Lane, A D; Yan, H; Ranadive, S M; Kappus, R M; Sun, P; Cook, M D; Harvey, I; Woods, J; Wilund, K; Fernhall, B

2014-12-01

Ventricular and vascular coupling is defined as the ratio of arterial elastance (Ea) to ventricular elastance (Elv) and describes the interaction between the heart and arterial system. There are sex differences in both arterial and ventricular function in response to both acute exercise and aerobic exercise training. To examine the effects of aerobic exercise training on elastances and the coupling ratio in young adult men and women. We hypothesized a reduction in the coupling ratio in both sexes due to a decrease in Ea that would be more pronounced in men and an increase in Elv that would be larger in women. Fifty-three healthy, young adults completed the study. Central pulse wave velocity and heart volumes were measured before and after an 8-week aerobic training intervention. Elastances were calculated as Ea = end-systolic pressure/stroke volume and Elv = end-systolic pressure/end-systolic volume and indexed to body surface area. After the intervention, women augmented indexed and un-indexed Elv from 2.09 ± 0.61 to 2.52 ± 0.80 mmHg/ml, p 0.05). Women also reduced end-systolic pressure (from 91 ± 10 to 87 ± 10 mmHg), and both groups reduced central pulse wave velocity (from 6.0 ± 1.0 to 5.6 ± 0.6 m/s, p < 0.05). We conclude that after 8 weeks of aerobic training, only women reduced their coupling ratio due to an increase in Elv. This suggests that aerobic exercise training elicits sex-dependent changes in the coupling ratio in young, healthy individuals.

A sigmoidal fit for pressure-volume curves of idiopathic pulmonary fibrosis patients on mechanical ventilation: clinical implications

Directory of Open Access Journals (Sweden)

Juliana C. Ferreira

2011-01-01

Full Text Available OBJECTIVE: Respiratory pressure-volume curves fitted to exponential equations have been used to assess disease severity and prognosis in spontaneously breathing patients with idiopathic pulmonary fibrosis. Sigmoidal equations have been used to fit pressure-volume curves for mechanically ventilated patients but not for idiopathic pulmonary fibrosis patients. We compared a sigmoidal model and an exponential model to fit pressure-volume curves from mechanically ventilated patients with idiopathic pulmonary fibrosis. METHODS: Six idiopathic pulmonary fibrosis patients and five controls underwent inflation pressure-volume curves using the constant-flow technique during general anesthesia prior to open lung biopsy or thymectomy. We identified the lower and upper inflection points and fit the curves with an exponential equation, V = A-B.e-k.P, and a sigmoid equation, V = a+b/(1+e-(P-c/d. RESULTS: The mean lower inflection point for idiopathic pulmonary fibrosis patients was significantly higher (10.5 ± 5.7 cm H2O than that of controls (3.6 ± 2.4 cm H2O. The sigmoidal equation fit the pressure-volume curves of the fibrotic and control patients well, but the exponential equation fit the data well only when points below 50% of the inspiratory capacity were excluded. CONCLUSION: The elevated lower inflection point and the sigmoidal shape of the pressure-volume curves suggest that respiratory system compliance is decreased close to end-expiratory lung volume in idiopathic pulmonary fibrosis patients under general anesthesia and mechanical ventilation. The sigmoidal fit was superior to the exponential fit for inflation pressure-volume curves of anesthetized patients with idiopathic pulmonary fibrosis and could be useful for guiding mechanical ventilation during general anesthesia in this condition.

Euglycemic clamp insulin sensitivity and longitudinal systolic blood pressure

DEFF Research Database (Denmark)

Petrie, John R; Malik, Muhammad Omar; Balkau, Beverley

2013-01-01

and Cardiovascular disease (RISC) study, we measured insulin sensitivity (M/I) using the euglycemic clamp technique in 1073 healthy European adults (587 women, 486 men) aged 30 to 60 years followed up 3 years later. Systolic BP (SBP) at baseline was higher in insulin-resistant women (ie, those in the low sex...

Systolic Blood Pressure Trajectory, Frailty, and All-Cause Mortality >80 Years of Age: Cohort Study Using Electronic Health Records.

Science.gov (United States)

Ravindrarajah, Rathi; Hazra, Nisha C; Hamada, Shota; Charlton, Judith; Jackson, Stephen H D; Dregan, Alex; Gulliford, Martin C

2017-06-13

Clinical trials show benefit from lowering systolic blood pressure (SBP) in people ≥80 years of age, but nonrandomized epidemiological studies suggest lower SBP may be associated with higher mortality. This study aimed to evaluate associations of SBP with all-cause mortality by frailty category >80 years of age and to evaluate SBP trajectories before death. A population-based cohort study was conducted using electronic health records of 144 403 participants ≥80 years of age registered with family practices in the United Kingdom from 2001 to 2014. Participants were followed for ≤5 years. Clinical records of SBP were analyzed. Frailty status was classified using the e-Frailty Index into the categories of fit, mild, moderate, and severe. All-cause mortality was evaluated by frailty status and mean SBP in Cox proportional-hazards models. SBP trajectories were evaluated using person months as observations, with mean SBP and antihypertensive treatment status estimated for each person month. Fractional polynomial models were used to estimate SBP trajectories over 5 years before death. During follow-up, 51 808 deaths occurred. Mortality rates increased with frailty level and were greatest at SBP mortality was 7.7 per 100 person years at SBP 120 to 139 mm Hg, 15.2 at SBP 110 to 119 mm Hg, and 22.7 at SBP mortality may be accounted for by reverse causation if participants with lower blood pressure values are closer, on average, to the end of life. © 2017 The Authors.

ω-3 Polyunsaturated fatty acids prevent pressure overload-induced ventricular dilation and decrease in mitochondrial enzymes despite no change in adiponectin

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O'Shea Karen M

2010-09-01

Full Text Available Abstract Background Pathological left ventricular (LV hypertrophy frequently progresses to dilated heart failure with suppressed mitochondrial oxidative capacity. Dietary marine ω-3 polyunsaturated fatty acids (ω-3 PUFA up-regulate adiponectin and prevent LV dilation in rats subjected to pressure overload. This study 1 assessed the effects of ω-3 PUFA on LV dilation and down-regulation of mitochondrial enzymes in response to pressure overload; and 2 evaluated the role of adiponectin in mediating the effects of ω-3 PUFA in heart. Methods Wild type (WT and adiponectin-/- mice underwent transverse aortic constriction (TAC and were fed standard chow ± ω-3 PUFA for 6 weeks. At 6 weeks, echocardiography was performed to assess LV function, mice were terminated, and mitochondrial enzyme activities were evaluated. Results TAC induced similar pathological LV hypertrophy compared to sham mice in both strains on both diets. In WT mice TAC increased LV systolic and diastolic volumes and reduced mitochondrial enzyme activities, which were attenuated by ω-3 PUFA without increasing adiponectin. In contrast, adiponectin-/- mice displayed no increase in LV end diastolic and systolic volumes or decrease in mitochondrial enzymes with TAC, and did not respond to ω-3 PUFA. Conclusion These findings suggest ω-3 PUFA attenuates cardiac pathology in response to pressure overload independent of an elevation in adiponectin.

Low Plasma Volume in Normotensive Formerly Preeclamptic Women Predisposes to Hypertension.

Science.gov (United States)

Scholten, Ralph R; Lotgering, Fred K; Hopman, Maria T; Van Dijk, Arie; Van de Vlugt, Maureen; Janssen, Mirian C H; Spaanderman, Marc E A

2015-11-01

Formerly preeclamptic women are at risk for cardiovascular disease. Low plasma volume may reflect latent hypertension and potentially links preeclampsia with chronic cardiovascular disease. We hypothesized that low plasma volume in normotensive formerly preeclamptic women predisposes to hypertension. We longitudinally studied n=104 formerly preeclamptic women in whom plasma volume was measured 3 to 30 months after the preeclamptic pregnancy. Cardiovascular variables were assessed at 2 points in time (3-30 months postpartum and 2-5 years thereafter). Study population was divided into low plasma volume (≤1373 mL/m(2)) and normal plasma volume (>1373 mL/m(2)). Primary end point was hypertension at the second visit: defined as ≥140 mm Hg systolic or ≥90 mm Hg diastolic. Secondary outcome of this study was change in traditional cardiovascular risk profile between visits. Variables correlating univariately with change in blood pressure between visits were introduced in regression analysis. Eighteen of 104 (17%) formerly preeclamptic women who were normotensive at first visit had hypertension at second evaluation 2 to 5 years later. Hypertension developed more often in women with low plasma volume (10/35 [29%]) than in women with normal plasma volume (8/69 [12%]; odds ratio, 3.2; 95% confidence interval, 1.4-8.6). After adjustments, relationship between plasma volume status and subsequent hypertension persisted (adjusted odds ratio, 3.0; 95% confidence interval, 1.1-8.5). Mean arterial pressure at second visit correlated inverse linearly with plasma volume (r=-0.49; Phypertension within 5 years. Women with low plasma volume have higher chance to develop hypertension than women with normal plasma volume. Clinically, follow-up of blood pressure seems warranted in women with history of preeclampsia, even when initially normotensive. © 2015 American Heart Association, Inc.

Minimally invasive estimation of ventricular dead space volume through use of Frank-Starling curves.

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Shaun Davidson

Full Text Available This paper develops a means of more easily and less invasively estimating ventricular dead space volume (Vd, an important, but difficult to measure physiological parameter. Vd represents a subject and condition dependent portion of measured ventricular volume that is not actively participating in ventricular function. It is employed in models based on the time varying elastance concept, which see widespread use in haemodynamic studies, and may have direct diagnostic use. The proposed method involves linear extrapolation of a Frank-Starling curve (stroke volume vs end-diastolic volume and its end-systolic equivalent (stroke volume vs end-systolic volume, developed across normal clinical procedures such as recruitment manoeuvres, to their point of intersection with the y-axis (where stroke volume is 0 to determine Vd. To demonstrate the broad applicability of the method, it was validated across a cohort of six sedated and anaesthetised male Pietrain pigs, encompassing a variety of cardiac states from healthy baseline behaviour to circulatory failure due to septic shock induced by endotoxin infusion. Linear extrapolation of the curves was supported by strong linear correlation coefficients of R = 0.78 and R = 0.80 average for pre- and post- endotoxin infusion respectively, as well as good agreement between the two linearly extrapolated y-intercepts (Vd for each subject (no more than 7.8% variation. Method validity was further supported by the physiologically reasonable Vd values produced, equivalent to 44.3-53.1% and 49.3-82.6% of baseline end-systolic volume before and after endotoxin infusion respectively. This method has the potential to allow Vd to be estimated without a particularly demanding, specialised protocol in an experimental environment. Further, due to the common use of both mechanical ventilation and recruitment manoeuvres in intensive care, this method, subject to the availability of multi-beat echocardiography, has the potential to

Reduced left ventricular filling following blood volume extraction does not result in compensatory augmentation of cardiac mechanics.

Science.gov (United States)

Lord, Rachel; MacLeod, David; George, Keith; Oxborough, David; Shave, Rob; Stembridge, Mike

2018-04-01

What is the central question of this study? A reduction in left ventricular (LV) filling, and concomitant increase in heart rate, augments LV mechanics to maintain stroke volume (SV); however, the impact of reduced LV filling in isolation on SV and LV mechanics is currently unknown. What is the main finding and its importance? An isolated decrease in LV filling did not provoke a compensatory increase in mechanics to maintain SV; in contrast, LV mechanics and SV were reduced. These data indicate that when LV filling is reduced without changes in heart rate, LV mechanics do not compensate to maintain SV. An acute non-invasive reduction in preload has been shown to augment cardiac mechanics to maintain stroke volume and cardiac output. Such interventions induce concomitant changes in heart rate, whereas blood volume extraction reduces preload without changes in heart rate. Therefore, the purpose of this study was to determine whether a preload reduction in isolation resulted in augmented stroke volume achieved via enhanced cardiac mechanics. Nine healthy volunteers (four female, age 29 ± 11 years) underwent echocardiography for the assessment of left ventricular (LV) volumes and mechanics in a supine position at baseline and end extraction after the controlled removal of 25% of total blood volume (1062 ± 342 ml). Arterial blood pressure was monitored continuously by a pressure transducer attached to an indwelling radial artery catheter. Heart rate and total peripheral resistance were unchanged from baseline to end extraction, but systolic blood pressure was reduced (from 148 to 127 mmHg). From baseline to end extraction there were significant reductions in left ventricular end-diastolic volume (from 89 to 71 ml) and stroke volume (from 56 to 37 ml); however, there was no change in LV twist, basal or apical rotation. In contrast, LV longitudinal strain (from -20 to -17%) and basal circumferential strain (from -22 to -19%) were significantly reduced from

Reduction in Left Ventricular Wall Stress and Improvement in Function in Failing Hearts using Algisyl-LVR

Science.gov (United States)

Lee, Lik Chuan; Zhihong, Zhang; Hinson, Andrew; Guccione, Julius M.

2013-01-01

Injection of Algisyl-LVR, a treatment under clinical development, is intended to treat patients with dilated cardiomyopathy. This treatment was recently used for the first time in patients who had symptomatic heart failure. In all patients, cardiac function of the left ventricle (LV) improved significantly, as manifested by consistent reduction of the LV volume and wall stress. Here we describe this novel treatment procedure and the methods used to quantify its effects on LV wall stress and function. Algisyl-LVR is a biopolymer gel consisting of Na+-Alginate and Ca2+-Alginate. The treatment procedure was carried out by mixing these two components and then combining them into one syringe for intramyocardial injections. This mixture was injected at 10 to 19 locations mid-way between the base and apex of the LV free wall in patients. Magnetic resonance imaging (MRI), together with mathematical modeling, was used to quantify the effects of this treatment in patients before treatment and at various time points during recovery. The epicardial and endocardial surfaces were first digitized from the MR images to reconstruct the LV geometry at end-systole and at end-diastole. Left ventricular cavity volumes were then measured from these reconstructed surfaces. Mathematical models of the LV were created from these MRI-reconstructed surfaces to calculate regional myofiber stress. Each LV model was constructed so that 1) it deforms according to a previously validated stress-strain relationship of the myocardium, and 2) the predicted LV cavity volume from these models matches the corresponding MRI-measured volume at end-diastole and end-systole. Diastolic filling was simulated by loading the LV endocardial surface with a prescribed end-diastolic pressure. Systolic contraction was simulated by concurrently loading the endocardial surface with a prescribed end-systolic pressure and adding active contraction in the myofiber direction. Regional myofiber stress at end-diastole and

Hemodynamic and radionuclide effects of acute captopril therapy for heart failure: changes in left and right ventricular volumes and function at rest and during exercise

International Nuclear Information System (INIS)

Massie, B.; Kramer, B.L.; Topic, N.; Henderson, S.G.

1982-01-01

Although the resting hemodynamic effects of captopril in congestive heart failure are known, little information is available about the hemodynamic response to captopril during exercise or about changes in noninvasive measurements of the size and function of both ventricles. In this study, 14 stable New York Heart Association class III patients were given 25 mg of oral captopril. Rest and exercise hemodynamic measurements and blood pool scintigrams were performed simultaneously before and 90 minutes after captopril. The radionuclide studies were analyzed for left and right ventricular end-diastolic volumes, end-systolic volumes, ejection fractions and pulmonary blood volume. The primary beneficial responses at rest were decreases in left and right ventricular end-diastolic volumes from 388 +/- 81 to 350 +/- 77 ml and from 52 +/- 26 to 43 +/- 20 volume units, respectively, and in their corresponding filling pressures, from 24 +/- 10 to 17 +/- 9 mm Hg and 10 +/- 5 to 6 +/- 5 mm Hg. Although stroke volume did not increase significantly, both left and right ventricular ejection fractions increased slightly, from 19 +/- 6% to 22+/- 5% and from 25 +/- 9% to 29 +/- 11%, respectively. During exercise, similar changes were noted in both hemodynamic and radionuclide indexes. This, in patients with moderate symptomatic limitation from chronic heart failure, captopril predominantly reduces ventricular volume and filling pressure, with a less significant effect on cardiac output. These effects persist during exercise, when systemic vascular resistance is already very low. Radionuclide techniques are valuable in assessing the drug effect in these subjects, particularly when ventricular volumes are also measured

Studies of left ventricular volume estimation from single photon emission computed tomography

International Nuclear Information System (INIS)

Hiraki, Yoshio; Shimizu, Mitsuharu; Joja, Ikuo; Aono, Kaname; Yanagi, Hidekiyo; Indo, Haruaki; Seno, Yoshimasa; Teramoto, Shigeru; Nagaya, Isao.

1988-01-01

We studied the comparative accuracy of 99m Tc cardiac blood pool Single Photon Emission Computed Tomography (SPECT) for the measurement of left ventricular volume in 20 patients undergoing SPECT and single plane contrast left ventriculography (LVG). Left ventricular volume was calculated based on the total number of voxels in left ventricle. End-diastolic left ventricular volume (EDV) and end-systolic left ventricular volume (ESV) calculated from SPECT were compared with those from LVG. SPECT volume values showed a high degree of correlation with those by LVG (r = 0.923 for EDV, r = 0.903 for ESV). We appreciated the usefulness and accuracy of SPECT in measuring left ventricular volume because of its three-dimensional information. (author)

Systolic Sac Pressure Index for the Prediction of Persistent Type II Endoleak for 12 Months After Endovascular Abdominal Aortic Aneurysm Repair

Energy Technology Data Exchange (ETDEWEB)

Ikoma, Akira, E-mail: yfb04322@nifty.com; Nakai, Motoki, E-mail: momonga@wakayama-med.ac.jp; Sato, Morio, E-mail: morisato@wakayama-med.ac.jp; Sato, Hirotatsu, E-mail: kuppa1220@yahoo.co.jp; Minamiguchi, Hiroki, E-mail: hiromina4@hotmail.com; Sonomura, Tetsuo, E-mail: sonomura@wakayama-med.ac.jp [Wakayama Medical University, Departments of Radiology (Japan); Nishimura, Yoshiharu, E-mail: nishim-y@wakayama-med.ac.jp; Okamura, Yoshitaka, E-mail: y-ok@wakayama-med.ac.jp [Wakayama Medical University, Thoracic and Cardiovascular Surgery (Japan)

2016-04-15

PurposeTo assess the relationship between the systolic sac pressure index (SPI) and the presence of endoleaks 12 months after endovascular abdominal aortic aneurysm repair (EVAR).Materials and MethodsWe performed a single-center prospective trial of consecutively treated patients. SPI (calculated as systolic sac pressure/systolic aortic pressure) was measured by catheterization immediately after EVAR. Contrast-enhanced computed tomography was scheduled 12 months after EVAR to detect possible endoleaks.ResultsData were available for 34 patients who underwent EVAR for an AAA. Persisting type II endoleak was found in 8 patients (endoleak-positive group) but not in the other 26 patients (endoleak-negative group). The mean ± standard deviation SPI was significantly greater in the endoleak-positive group than in the endoleak-negative group (0.692 ± 0.048 vs. 0.505 ± 0.081, respectively; P = .001). Receiver-operating characteristic curve analysis revealed that an SPI of 0.638 was the optimum cutoff value for predicting a persistent endoleak at 12 months with high accuracy (0.971; 33/34), sensitivity (1.00), and specificity (0.962) values. The mean change in AAA diameter was −4.28 ± 5.03 mm and 2.22 ± 4.54 mm in patients with SPI of <0.638 or ≥0.638, respectively (P = .002).ConclusionPatients with an SPI of ≥0.638 immediately after EVAR were more likely to have a persistent type II endoleak at 12 months with an accuracy of 0.971, and showed increases in aneurysm sac diameter compared with patients with an SPI of <0.638.

Intraoperative protective mechanical ventilation for prevention of postoperative pulmonary complications: a comprehensive review of the role of tidal volume, positive end-expiratory pressure, and lung recruitment maneuvers.

Science.gov (United States)

Güldner, Andreas; Kiss, Thomas; Serpa Neto, Ary; Hemmes, Sabrine N T; Canet, Jaume; Spieth, Peter M; Rocco, Patricia R M; Schultz, Marcus J; Pelosi, Paolo; Gama de Abreu, Marcelo

2015-09-01

Postoperative pulmonary complications are associated with increased morbidity, length of hospital stay, and mortality after major surgery. Intraoperative lung-protective mechanical ventilation has the potential to reduce the incidence of postoperative pulmonary complications. This review discusses the relevant literature on definition and methods to predict the occurrence of postoperative pulmonary complication, the pathophysiology of ventilator-induced lung injury with emphasis on the noninjured lung, and protective ventilation strategies, including the respective roles of tidal volumes, positive end-expiratory pressure, and recruitment maneuvers. The authors propose an algorithm for protective intraoperative mechanical ventilation based on evidence from recent randomized controlled trials.

Non-invasive aortic systolic pressure and pulse wave velocity estimation in a primary care setting: An in silico study.

Science.gov (United States)

Guala, Andrea; Camporeale, Carlo; Ridolfi, Luca; Mesin, Luca

2017-04-01

Everyday clinical cardiovascular evaluation is still largely based on brachial systolic and diastolic pressures. However, several clinical studies have demonstrated the higher diagnostic capacities of the aortic pressure, as well as the need to assess the aortic mechanical properties (e.g., by measuring the aortic pulse wave velocity). In order to fill this gap, we propose to exploit a set of easy-to-obtain physical characteristics to estimate the aortic pressure and pulse wave velocity. To this aim, a large population of virtual subjects is created by a validated mathematical model of the cardiovascular system. Quadratic regressive models are then fitted and statistically selected in order to obtain reliable estimations of the aortic pressure and pulse wave velocity starting from the knowledge of the subject age, height, weight, brachial pressure, photoplethysmographic measures and either electrocardiogram or phonocardiogram. The results are very encouraging and foster clinical studies aiming to apply a similar technique to a real population. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

Geophysics Under Pressure: Large-Volume Presses Versus the Diamond-Anvil Cell

Science.gov (United States)

Hazen, R. M.

2002-05-01

Prior to 1970, the legacy of Harvard physicist Percy Bridgman dominated high-pressure geophysics. Massive presses with large-volume devices, including piston-cylinder, opposed-anvil, and multi-anvil configurations, were widely used in both science and industry to achieve a range of crustal and upper mantle temperatures and pressures. George Kennedy of UCLA was a particularly influential advocate of large-volume apparatus for geophysical research prior to his death in 1980. The high-pressure scene began to change in 1959 with the invention of the diamond-anvil cell, which was designed simultaneously and independently by John Jamieson at the University of Chicago and Alvin Van Valkenburg at the National Bureau of Standards in Washington, DC. The compact, inexpensive diamond cell achieved record static pressures and had the advantage of optical access to the high-pressure environment. Nevertheless, members of the geophysical community, who favored the substantial sample volumes, geothermally relevant temperature range, and satisfying bulk of large-volume presses, initially viewed the diamond cell with indifference or even contempt. Several factors led to a gradual shift in emphasis from large-volume presses to diamond-anvil cells in geophysical research during the 1960s and 1970s. These factors include (1) their relatively low cost at time of fiscal restraint, (2) Alvin Van Valkenburg's new position as a Program Director at the National Science Foundation in 1964 (when George Kennedy's proposal for a Nation High-Pressure Laboratory was rejected), (3) the development of lasers and micro-analytical spectroscopic techniques suitable for analyzing samples in a diamond cell, and (4) the attainment of record pressures (e.g., 100 GPa in 1975 by Mao and Bell at the Geophysical Laboratory). Today, a more balanced collaborative approach has been adopted by the geophysics and mineral physics community. Many high-pressure laboratories operate a new generation of less expensive

Predictors of high central blood pressure in young with isolated systolic hypertension

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Radchenko GD

2016-08-01

Full Text Available G D Radchenko, O O Torbas, Yu M Sirenko State Institute National Scientific Center, M.D. Strazhesko Institute of Cardiology, National Academy of Medical Science, Kyiv, Ukraine Objective: According to the European Society of Cardiology/European Society of Hypertension 2013 guidelines, evaluation of aortic blood pressure (BP is needed in young with isolated systolic hypertension (ISH, but using special devices is not common, especially in Ukraine, where only a few centers have these devices. The purpose of our study was to identify the simple clinical predictors for differentiation (with or without elevated aortic systolic BP [SBP] of the young with ISH without the need for further extensive work-up. Patients and methods: The study included 44 young men (mean age: 32.2±1.3 years with office SBP ≥140 mmHg and office diastolic BP (DBP <90 mmHg (average: 153.4±2.1 mmHg and 83.4±1.7 mmHg, respectively. The following procedures were performed in all the subjects: body weight and height evaluation; measurement of office SBP, DBP, and heart rate; ambulatory BP monitoring; measurement of pulse wave velocity in arteries of elastic and muscle types and central SBP (cSBP; biochemical blood tests; electrocardiography; echocardiography; and carotid ultrasound investigations. Step-by-step multifactor regression analyses were used for finding the predictors of high cSBP. Results: Depending on the cSBP level, all the patients were divided into two groups: first group (n=17, subjects with normal cSBP, and second group (n=27, subjects with elevated cSBP. Patients in the second group were significantly older, with less height and higher body mass index; they had significantly higher levels of office SBP and DBP. Characteristics of target organ damage were within normal limits in both groups and did not differ significantly. Only pulse wave velocity in arteries of elastic type was significantly higher in the second group. The independent predictors of

Myocardial contractility in the echo lab: molecular, cellular and pathophysiological basis

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Bombardini Tonino

2005-09-01

fails, there is a change in the gene expression from the normal adult pattern to that of fetal life with an inversion of the normal positive slope of the force-frequency relation: systolic calcium release and diastolic calcium reuptake process is lowered at the basal state and, instead of accelerating for increasing heart rates, slows down. Since the force-frequency relation uncovers initial alteration of contractility, as an intermediate step between normal and abnormal contractility at rest, a practical index to measure it is mandatory. Measuring end-systolic elastance for increasing heart rates is impractical: increasing heart rates with atrial pacing has to be adjunct to the left ventricular conductance catheter, to the left ventricular pressure catheter, to the vena cava balloon, and to afterload changes. Furthermore, a noninvasive index is needed. Noninvasive measurement of the pressure/volume ratio for increasing heart rates during stress in the echo lab could be the practical answer to this new clinical demand in the current years of a dramatic increase in the number of heart failure patients.

Heart Rate and Systolic Blood Pressure Variability on Recently Diagnosed Diabetics

Directory of Open Access Journals (Sweden)

Anaclara Michel-Chávez

2015-01-01

Full Text Available Background: Diabetes affects approximately 250 million people in the world. Cardiovascular autonomic neuropathy is a common complication of diabetes that leads to severe postural hypotension, exercise intolerance, and increased incidence of silent myocardial infarction. Objective: To determine the variability of heart rate (HR and systolic blood pressure (SBP in recently diagnosed diabetic patients. Methods: The study included 30 patients with a diagnosis of type 2 diabetes of less than 2 years and 30 healthy controls. We used a Finapres® device to measure during five minutes beat-to-beat HR and blood pressure in three experimental conditions: supine position, standing position, and rhythmic breathing at 0.1 Hz. The results were analyzed in the time and frequency domains. Results: In the HR analysis, statistically significant differences were found in the time domain, specifically on short-term values such as standard deviation of NN intervals (SDNN, root mean square of successive differences (RMSSD, and number of pairs of successive NNs that differ by more than 50 ms (pNN50. In the BP analysis, there were no significant differences, but there was a sympathetic dominance in all three conditions. The baroreflex sensitivity (BRS decreased in patients with early diabetes compared with healthy subjects during the standing maneuver. Conclusions: There is a decrease in HR variability in patients with early type 2 diabetes. No changes were observed in the BP analysis in the supine position, but there were changes in BRS with the standing maneuver, probably due to sympathetic hyperactivity.

[Central blood pressure and vascular damage].

Science.gov (United States)

Pérez-Lahiguera, Francisco; Rodilla, Enrique; Costa, José Antonio; Pascual, José María

2015-07-20

The aim of this study was to assess the relationship between central blood pressure and vascular damage. This cross-sectional study involved 393 never treated hypertensive patients (166 women). Clinical blood pressure (BP), 24h blood pressure (BP24h) and central blood pressure (CBP) were measured. Vascular organ damage (VOD) was assessed by calculating the albumin/creatinine ratio (ACR), wave pulse pressure velocity and echocardiographic left ventricular mass index (LVMI). Patients with VOD had higher values of BP, BP24h, and CBP than patients without ACR. When comparing several systolic BP, systolic BP24h had a higher linear correlation with CBP (Z Steiger test: 2.26; P=.02) and LVMI (Z Steiger test: 3.23; P=.01) than PAC. In a multiple regression analysis corrected by age, sex and metabolic syndrome, all pressures were related with VOD but systolic BP24h showed the highest correlation. In a logistic regression analysis, having the highest tercile of systolic BP24h was the stronger predictor of VOD (multivariate odds ratio: 3.4; CI 95%: 2.5-5.5, P=.001). CBP does not have more correlation with VOD than other measurements of peripheral BP. Systolic BP24h is the BP measurement that best predicts VOD. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

Inter-arm blood pressure differences in pregnant women.

Science.gov (United States)

Poon, L C Y; Kametas, N; Strobl, I; Pachoumi, C; Nicolaides, K H

2008-08-01

To determine the prevalence of blood pressure inter-arm difference (IAD) in early pregnancy and to investigate its possible association with maternal characteristics. A cross-sectional observational study. Routine antenatal visit in a university hospital. A total of 5435 pregnant women at 11-14 weeks of gestation. Blood pressure was taken from both arms simultaneously with a validated automated device. The presence of inter-arm blood pressure difference of 10 mmHg or more. The IAD in systolic and diastolic blood pressure was 10 mmHg or more in 8.3 and 2.3% of the women, respectively. Systolic IAD was found to be significantly related to systolic blood pressure and pulse pressure, and diastolic IAD was found to be significantly related to maternal age, diastolic blood pressure and pulse pressure. The systolic and diastolic IAD were higher in the hypertensive group compared with the normotensive group and absolute IAD increased with increasing blood pressure. About 31.0 and 23.9% of cases of hypertension would have been underreported if the left arm and the right arm were used, respectively, in measuring the blood pressure. There is a blood pressure IAD in a significant proportion of the pregnant population, and its prevalence increases with increasing blood pressure. By measuring blood pressure only on one arm, there is a one in three chance of underreporting hypertension. Therefore, it would be prudent that during the booking visit blood pressure should be taken in both arms and thus provide guidance for subsequent blood pressure measurements during the course of pregnancy.

Cuffless differential blood pressure estimation using smart phones.

Science.gov (United States)

Chandrasekaran, Vikram; Dantu, Ram; Jonnada, Srikanth; Thiyagaraja, Shanti; Subbu, Kalyan Pathapati

2013-04-01

Smart phones today have become increasingly popular with the general public for their diverse functionalities such as navigation, social networking, and multimedia facilities. These phones are equipped with high-end processors, high-resolution cameras, and built-in sensors such as accelerometer, orientation-sensor, and light-sensor. According to comScore survey, 26.2% of U.S. adults use smart phones in their daily lives. Motivated by this statistic and the diverse capability of smart phones, we focus on utilizing them for biomedical applications. We present a new application of the smart phone with its built-in camera and microphone replacing the traditional stethoscope and cuff-based measurement technique, to quantify vital signs such as heart rate and blood pressure. We propose two differential blood pressure estimating techniques using the heartbeat and pulse data. The first method uses two smart phones whereas the second method replaces one of the phones with a customized external microphone. We estimate the systolic and diastolic pressure in the two techniques by computing the pulse pressure and the stroke volume from the data recorded. By comparing the estimated blood pressure values with those measured using a commercial blood pressure meter, we obtained encouraging results of 95-100% accuracy.

Lung volumes and maximal respiratory pressures in collegiate swimmers and runners.

Science.gov (United States)

Cordain, L; Tucker, A; Moon, D; Stager, J M

1990-03-01

To determine whether respiratory muscle strength is related to pulmonary volume differences in athletes and nonathletes, 11 intercollegiate female swimmers, 11 female cross-country runners, and two nonathletic control groups, matched to the athletes in height and age, were evaluated for pulmonary parameters including maximal inspiratory pressure (PImax) and maximal expiratory pressure (PEmax). Swimmers exhibited larger (p less than .05) vital capacities (VC), residual lung volumes (RV), inspiratory capacities (IC), and functional residual capacities (FRC) than both the runners or the controls but no difference (p greater than .05) in either PImax or inspiratory flow (FIV 25%-75%). Timed expiratory volumes (FEV 0.5 and FEV 1.0) were significantly (p less than .05) lower in the swimmers than in the controls. These data suggest that an adaptational growth may be responsible, in part, for the augmented static lung volumes demonstrated in swimmers.

Fourier series analysis of a cylindrical pressure vessel subjected to axial end load and external pressure

International Nuclear Information System (INIS)

Brar, Gurinder Singh; Hari, Yogeshwar; Williams, Dennis K.

2013-01-01

This paper presents the comparison of a reliability technique that employs a Fourier series representation of random axisymmetric and asymmetric imperfections in a cylindrical pressure vessel subjected to an axial end load and external pressure, with evaluations prescribed by the ASME Boiler and Pressure Vessel Code, Section VIII, Division 2 Rules. The ultimate goal of the reliability technique described herein is to predict the critical buckling load associated with the subject cylindrical pressure vessel. Initial geometric imperfections are shown to have a significant effect on the calculated load carrying capacity of the vessel. Fourier decomposition was employed to interpret imperfections as structural features that can be easily related to various other types of defined imperfections. The initial functional description of the imperfections consists of an axisymmetric portion and a deviant portion, which are availed in the form of a double Fourier series. Fifty simulated shells generated by the Monte Carlo technique are employed in the final prediction of the critical buckling load. The representation of initial geometrical imperfections in the cylindrical pressure vessel requires the determination of respective Fourier coefficients. Multi-mode analyses are expanded to evaluate a large number of potential buckling modes for both predefined geometries in combination with asymmetric imperfections as a function of position within the given cylindrical shell. The probability of the ultimate buckling stress exceeding a predefined threshold stress is also calculated. The method and results described herein are in stark contrast to the “knockdown factor” approach as applied to compressive stress evaluations currently utilized in industry. Further effort is needed to improve on the current design rules regarding column buckling of large diameter pressure vessels subjected to an axial end load and external pressure designed in accordance with ASME Boiler and

Observation of the pulse oximeter trace to estimate systolic blood ...

African Journals Online (AJOL)

Background: The estimation of systolic blood pressure by disappearance and reappearance of the pulse oximeter trace during cuff inflation and deflation was compared with non-invasive blood pressure (NIBP) measurement, across the range of body mass index (BMI), during spinal anaesthesia for Caesarean section.

The Relationship Between the Metabolic Syndrome and Systolic Inter-Arm Systolic Blood Pressure Difference in Korean Adults.

Science.gov (United States)

Yoon, Hyun; Choi, Seong Woo; Park, Jong; Ryu, So Yeon; Han, Mi Ah; Kim, Gwang Seok; Kim, Sung Gil; Oh, Hye Jong; Choi, Cheol Won

2015-10-01

The present study was conducted to assess the relationship between metabolic syndrome and systolic inter-arm blood pressure difference (sIAD) in Korean adults. This study included 410 adults (235 males, 175 females) who were over 30 years old and had undergone a health check from July to December in 2013. The incidence of high sIAD and metabolic syndrome were 23.4% and 23.2%, respectively. Key study results were as follows: First, the sIAD levels increased significantly with an increase in metabolic syndrome score (p<0.001), shown by sIAD levels after adjusted the variables that affect sIAD levels (age, gender, smoking, drinking, exercising, total cholesterol, and body mass index). These were 4.6±0.7 mmHg for metabolic syndrome score (MSS) 0; 5.8±0.5 mmHg for MSS 1; 6.2±0.6 mmHg for MSS 2, 9.2±0.8 mmHg for MSS 3; and 9.9±1.2 mmHg for MSS ≥4 (p<0.001). Second, the sIAD level of the metabolic syndrome group (9.3±0.7 mmHg) was significantly higher (p<0.001) than for the nonmetabolic syndrome group (5.7±0.3 mmHg). In conclusion, metabolic syndrome and an increased number of its components are associated with the sIAD levels in Korean adults.

Positive pressure ventilation and cranial volume in newborn infants.

OpenAIRE

Milligan, D W

1981-01-01

The relationship between changes in airways pressure, pleural pressure, and cranial volume was studied in a group of sick newborn infants requiring ventilatory assistance. Cranial volume increased appreciably only when lung compliance was such that more than 20% of the applied airways pressure was transmitted to the pleural space, or if the absolute pleural pressure was greater than 4 cmH2O above atmospheric pressure. The findings stress the need for more-critical monitoring during periods of...

Trial occlusion to assess the risk of persistent pulmonary arterial hypertension after closure of a large patent ductus arteriosus in adolescents and adults with elevated pulmonary artery pressure.

Science.gov (United States)

Zhang, Duan-Zhen; Zhu, Xian-Yang; Lv, Bei; Cui, Chun-Sheng; Han, Xiu-Min; Sheng, Xiao-Tang; Wang, Qi-Guang; Zhang, Po

2014-08-01

No method is available to predict whether patients with patent ductus arteriosus (PDA) and severe pulmonary arterial hypertension (PAH) will show persistent postprocedural PAH (PP-PAH) after PDA closure. This study evaluated the usefulness of trial occlusion for predicting PP-PAH after transcatheter PDA closure in patients with severe PAH. Trial occlusion was performed in 137 patients (age ≥12 years) with PDA and severe PAH. All patients undergoing trial occlusion had a mean pulmonary artery pressure ≥45 mm Hg, pulmonary:systemic flow (Qp/Qs) ratio >1.5, and pulmonary:systemic resistance (Rp/Rs) ratio closure. Linear correlation analysis revealed weak or moderate relationships between the baseline and post-trial pulmonary artery pressures and pulmonary:systemic pressure (Pp/Ps) ratios. Patients were followed up for 1 to 10 years (median: 5 years). PP-PAH (systolic pulmonary artery pressure >50 mm Hg by Doppler echocardiography) was detected in 17 patients (13%), who displayed no significant differences in sex and age compared with patients without PP-PAH. According to discriminant analysis, the strongest discriminators between patients with and without PP-PAH were the baseline left ventricular end-diastolic volume and the baseline and post-trial systolic Pp/Ps ratios. In particular, a post-trial systolic Pp/Ps ratio >0.5 correctly classified 100% of the PP-PAH and non-PAH patients. Trial occlusion is a feasible method to predict PP-PAH in patients with PDA and severe PAH. A post-trial systolic Pp/Ps ratio >0.5 indicates a high risk of PP-PAH occurrence after device closure. © 2014 American Heart Association, Inc.

Interarm differences in systolic blood pressure and mortality among US army veterans

DEFF Research Database (Denmark)

White, James; Mortensen, Laust Hvas; Kivimäki, Mika

2014-01-01

BACKGROUND: Differences between the arms in systolic blood pressure (SBP) of ≥10 mmHg have been associated with an increased risk of mortality in patients with hypertensive and chronic renal disease. For the first time, we examined these relationships in a non-clinical population. DESIGN: Cohort...... an interarm difference of ≥10 and 2.4% of ≥15 mmHg. A 15-year follow-up period gave rise to 246 deaths (64 from cardiovascular disease, CVD). Interarm differences of ≥10 mmHg were associated with an elevated risk of all-cause mortality (hazard ratio, HR, 1.49, 95% confidence interval, CI, 1.04-2.14) and CVD...... mortality (HR 1.93, 95% CI 1.01-3.69). After adjusting for SBP, DBP, lipids, fasting glucose, and erythrocyte sedimentation rate, associations between interarm differences of ≥10 mmHg and all-cause mortality (HR 1.35, 95% CI 0.94-1.95) and CVD mortality (1.62, 95% CI 0.84-3.14) were significantly attenuated...

Physiologic Evaluation of Ventilation Perfusion Mismatch and Respiratory Mechanics at Different Positive End-expiratory Pressure in Patients Undergoing Protective One-lung Ventilation.

Science.gov (United States)

Spadaro, Savino; Grasso, Salvatore; Karbing, Dan Stieper; Fogagnolo, Alberto; Contoli, Marco; Bollini, Giacomo; Ragazzi, Riccardo; Cinnella, Gilda; Verri, Marco; Cavallesco, Narciso Giorgio; Rees, Stephen Edward; Volta, Carlo Alberto

2018-03-01

Arterial oxygenation is often impaired during one-lung ventilation, due to both pulmonary shunt and atelectasis. The use of low tidal volume (VT) (5 ml/kg predicted body weight) in the context of a lung-protective approach exacerbates atelectasis. This study sought to determine the combined physiologic effects of positive end-expiratory pressure and low VT during one-lung ventilation. Data from 41 patients studied during general anesthesia for thoracic surgery were collected and analyzed. Shunt fraction, high V/Q and respiratory mechanics were measured at positive end-expiratory pressure 0 cm H2O during bilateral lung ventilation and one-lung ventilation and, subsequently, during one-lung ventilation at 5 or 10 cm H2O of positive end-expiratory pressure. Shunt fraction and high V/Q were measured using variation of inspired oxygen fraction and measurement of respiratory gas concentration and arterial blood gas. The level of positive end-expiratory pressure was applied in random order and maintained for 15 min before measurements. During one-lung ventilation, increasing positive end-expiratory pressure from 0 cm H2O to 5 cm H2O and 10 cm H2O resulted in a shunt fraction decrease of 5% (0 to 11) and 11% (5 to 16), respectively (P ventilation, high positive end-expiratory pressure levels improve pulmonary function without increasing high V/Q and reduce driving pressure.

Volume-dependent hemodynamic effects of blood collection in canine donors - evaluation of 13% and 15% of total blood volume depletion

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RUI R.F. FERREIRA

2015-03-01

Full Text Available Background: There is no consensus regarding the blood volume that could be safely donated by dogs, ranging from 11 to 25% of its total blood volume (TBV. No previous studies evaluated sedated donors.Aim: To evaluate the hemodynamic effects of blood collection from sedated and non-sedated dogs and to understand if such effects were volume-dependent.Materials and Methods: Fifty three donations of 13% of TBV and 20 donations of 15% TBV were performed in dogs sedated with diazepam and ketamine. Additionally, a total of 30 collections of 13% TBV and 20 collections of 15% TBV were performed in non-sedated dogs. Non-invasive arterial blood pressures and pulse rates were registered before and 15 min after donation. Results: Post-donation pulse rates increased significantly in both sedated groups, with higher differences in the 15% TBV collections. Systolic arterial pressures decreased significantly in these groups, while diastolic pressures increased significantly in 13% TBV donations. Non-sedated groups revealed a slight, but significant, SBP decrease. No clinical signs related to donations were registered.Conclusion: These results suggest that the collection of 15% TBV in sedated donors induces hemodynamic variations that may compromise the harmlessness of the procedure, while it seems to be a safe procedure in non-sedated dogs.

Development of a Blood Pressure Measurement Instrument with Active Cuff Pressure Control Schemes

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Chung-Hsien Kuo

2017-01-01

Full Text Available This paper presents an oscillometric blood pressure (BP measurement approach based on the active control schemes of cuff pressure. Compared with conventional electronic BP instruments, the novelty of the proposed BP measurement approach is to utilize a variable volume chamber which actively and stably alters the cuff pressure during inflating or deflating cycles. The variable volume chamber is operated with a closed-loop pressure control scheme, and it is activated by controlling the piston position of a single-acting cylinder driven by a screw motor. Therefore, the variable volume chamber could significantly eliminate the air turbulence disturbance during the air injection stage when compared to an air pump mechanism. Furthermore, the proposed active BP measurement approach is capable of measuring BP characteristics, including systolic blood pressure (SBP and diastolic blood pressure (DBP, during the inflating cycle. Two modes of air injection measurement (AIM and accurate dual-way measurement (ADM were proposed. According to the healthy subject experiment results, AIM reduced 34.21% and ADM reduced 15.78% of the measurement time when compared to a commercial BP monitor. Furthermore, the ADM performed much consistently (i.e., less standard deviation in the measurements when compared to a commercial BP monitor.

Mechanisms of blood pressure changes following renal irradiation of intact, adrenalectomized, and adrenal regenerating rats

International Nuclear Information System (INIS)

Rosenblum, M.

1977-01-01

This study was conducted to determine the differences in changes in systolic arterial blood pressure following renal x irradiation (1100 R) in adrenal-intact, adrenalectomized, and adrenal-regenerating rats and to elucidate the involvement or roles of the kidneys and of the adrenal glands in the blood pressure changes. The parameters studied included the following: systolic blood pressure; body weight; food and fluid consumption; urine output; plasma and urine electrolytes; sodium balance; plasma renin activity; plasma corticosterone; renal vascular volume; renal vascular permeability (using 125 I-polyvinylpyrrolidone extravasation rate as an indicator); renal blood flow (using 42 K extraction); kidney weight; hematocrit; and total vascular, plasma, and red cell volumes. Renal x irradiation of intact rats caused polydipsia, polyuria, and reduced urine concentrations of sodium and potassium without significantly affecting blood pressure during the period of study (80 days); plasma renin activity was significantly lowered and had a positive correlation with blood volume; an abnormal blood volume-plasma renin activity relationship is suggested. Adrenalectomy caused prolonged hypotension in saline-maintained rats even though their sodium balance was more positive than that in adrenal-intact or adrenal-regenerating rats with normal or elevated blood pressure. The blood pressure of renally irrradiated, adrenalectomized rats was greater than non-irradiated adrenalectomized rats, but with only borderline significance; it is concluded that the absence of the adrenal glands does not affect the degree or duration of the effects of renal irradiation on blood pressure

Significance of White-Coat Hypertension in Older Persons With Isolated Systolic Hypertension

Science.gov (United States)

Franklin, Stanley S.; Thijs, Lutgarde; Hansen, Tine W.; Li, Yan; Boggia, José; Kikuya, Masahiro; Björklund-Bodegård, Kristina; Ohkubo, Takayoshi; Jeppesen, Jørgen; Torp-Pedersen, Christian; Dolan, Eamon; Kuznetsova, Tatiana; Stolarz-Skrzypek, Katarzyna; Tikhonoff, Valérie; Malyutina, Sofia; Casiglia, Edoardo; Nikitin, Yuri; Lind, Lars; Sandoya, Edgardo; Kawecka-Jaszcz, Kalina; Imai, Yutaka; Wang, Jiguang; Ibsen, Hans; O’Brien, Eoin; Staessen, Jan A.

2013-01-01

The significance of white-coat hypertension in older persons with isolated systolic hypertension remains poorly understood. We analyzed subjects from the population-based 11-country International Database on Ambulatory Blood Pressure Monitoring in Relation to Cardiovascular Outcomes database who had daytime ambulatory blood pressure (BP; ABP) and conventional BP (CBP) measurements. After excluding persons with diastolic hypertension by CBP (≥90 mm Hg) or by daytime ABP (≥85 mm Hg), a history of cardiovascular disease, and persons hypertension. During a median follow-up of 10.6 years, there was a total of 655 fatal and nonfatal cardiovascular events. The analyses were stratified by treatment status. In untreated subjects, those with white-coat hypertension (CBP ≥140/hypertension, the cardiovascular risk was similar in elevated conventional and normal daytime systolic BP as compared with those with normal conventional and normal daytime BPs (adjusted hazard rate: 1.10 [95% CI: 0.79–1.53]; P=0.57). However, both treated isolated systolic hypertension subjects with white-coat hypertension (adjusted hazard rate: 2.00; [95% CI: 1.43–2.79]; Phypertension who have their ABP normalized on antihypertensive therapy but with residual white-coat effect by CBP measurement have an entity that we have termed, “treated normalized hypertension.” Therefore, one should be cautious in applying the term “white-coat hypertension” to persons receiving antihypertensive treatment. PMID:22252396

Factors affecting accuracy of ventricular volume and ejection fraction measured by gated Tl-201 myocardial perfusion single photon emission computed tomography

International Nuclear Information System (INIS)

Pai, Moon Sun; Yang, You Jung; Im, Ki Chun; Hong, Il Ki; Yun, Sung Cheol; Kang, Duk Hyun; Song, Jae Kwan; Moon, Dae Hyuk

2005-01-01

Systemic errors in the gated single photon emission computed tomography (SPECT) measurement of left ventricular (LV) end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) may occur. We evaluated whether patient-related factors affected the accuracy of EDV, ESV, and EF measured by electrocardiogram-gated Tl-201 SPECT. A total of 518 patients without perfusion defects on Tl-201 SPECT or coronary artery disease were studied. EDV, ESV, and EF were measured from echocardiography and adenosine stress/redistribution gated Tl-201 SPECT using commercially available software packages (QGS and 4D-MSPECT). We identified factors affecting the accuracy of gated SPECT via multiple linear regression analysis of the differences between echocardiography and gated SPECT. Gated SPECT analyzed with QGS underestimated EDV and ESV, and overestimated EF, but 4D-MSPECT overestimated all those values (p<0.001). Independent variables that increased the difference in EDV between echocardiography and gated SPECT were decreasing LV end-diastolic wall thickness, decreasing body surface area, female sex and increasing EDV (p< 0.001). Those for ESV were decreasing LV end-systolic wall thickness, female sex, and decreasing ESV (p<0.001). Increasing end-systolic wall thickness, male sex and decreasing age were independent determinants associated with an increased difference in EF (p< 0.001). Adenosine stress SPECT showed significantly higher EDV and ESV values and a lower EF than did redistribution SPECT (p< 0.001). In determination of EF, QGS demonstrated a smaller bias than did 4D-MSPECT. However, in men with LV hypertrophy, 4D-MSPECT was superior to QGS. Systemic error by gated Tl-201 SPECT is determined by individual patient-characteristics

A relative difference in systolic blood pressure between arms by synchronal measurement and conventional cardiovascular risk factors are associated with the severity of coronary atherosclerosis.

Science.gov (United States)

Yamamoto, Tomohiko; Miura, Shin-Ichiro; Suematsu, Yasunori; Kuwano, Takashi; Sugihara, Makoto; Ike, Amane; Iwata, Atsushi; Nishikawa, Hiroaki; Saku, Keijiro

2016-06-01

It is not known the relationships between a difference in systolic blood pressure (SBP) or diastolic BP (DBP) between arms by synchronal measurement and the presence of coronary artery disease (CAD), and between a difference in BP between arms and the severity of coronary atherosclerosis. We enrolled 425 consecutive patients (M/F = 286/139, 67 ± 13 year) who were admitted to our University Hospital and in whom we could measure the absolute (|rt. BP - lt. BP|) and relative (rt. BP - lt. BP) differences in SBP and DBP using a nico PS-501(®) (Parama-Tech). We divided all patients into those who did and did not have CAD. The relative differences in SBP between arms in patients with CAD were significantly lower than those in patients without CAD. However, the relative difference in SBP between arms was not a predictor of the presence of CAD. We also divided 267 patients who underwent coronary angiography into tertiles according to the Gensini score (low, middle, and high score groups). Interestingly, the middle + high score groups showed significantly lower relative differences in SBP between arms than the low score group. The mean Korotkoff sound graph in the middle + high Gensini score group was significantly higher than that in the low Gensini score group. Among conventional cardiovascular risk factors and nico parameters, the relative difference in SBP between arms in addition to the risk factors (age, gender, body mass index, hypertension, dyslipidemia, and diabetes mellitus) was associated with the score by a logistic regression analysis. In conclusion, the relative difference in SBP between arms as well as conventional risk factors may be associated with the severity of coronary arteriosclerosis.

Pressure and volume in the first law of black hole thermodynamics

Science.gov (United States)

Dolan, Brian P.

2011-12-01

The mass of a black hole is interpreted, in terms of thermodynamic potentials, as being the enthalpy, with the pressure given by the cosmological constant. The volume is then defined as being the Legendre transform of the pressure, and the resulting relation between volume and pressure is explored in the case of positive pressure. A virial expansion is developed and a van der Waals like critical point determined. The first law of black hole thermodynamics includes a PdV term which modifies the maximal efficiency of a Penrose process. It is shown that, in four-dimensional spacetime with a negative cosmological constant, an extremal charged rotating black hole can have an efficiency of up to 75%, while for an electrically neutral rotating black hole this figure is reduced to 52%, compared to the corresponding values of 50% and 29% respectively when the cosmological constant is zero.

Pressure and volume in the first law of black hole thermodynamics

International Nuclear Information System (INIS)

Dolan, Brian P

2011-01-01

The mass of a black hole is interpreted, in terms of thermodynamic potentials, as being the enthalpy, with the pressure given by the cosmological constant. The volume is then defined as being the Legendre transform of the pressure, and the resulting relation between volume and pressure is explored in the case of positive pressure. A virial expansion is developed and a van der Waals like critical point determined. The first law of black hole thermodynamics includes a PdV term which modifies the maximal efficiency of a Penrose process. It is shown that, in four-dimensional spacetime with a negative cosmological constant, an extremal charged rotating black hole can have an efficiency of up to 75%, while for an electrically neutral rotating black hole this figure is reduced to 52%, compared to the corresponding values of 50% and 29% respectively when the cosmological constant is zero. (paper)

Effects of Sacubitril/Valsartan Versus Olmesartan on Central Hemodynamics in the Elderly With Systolic Hypertension: The PARAMETER Study.

Science.gov (United States)

Williams, Bryan; Cockcroft, John R; Kario, Kazuomi; Zappe, Dion H; Brunel, Patrick C; Wang, Qian; Guo, Weinong

2017-03-01

Effective treatment of systolic hypertension in elderly patients remains a major therapeutic challenge. A multicenter, double-blind, randomized controlled trial with sacubitril/valsartan (LCZ696), a first-in-class angiotensin receptor neprilysin inhibitor, was conducted to determine its effects versus olmesartan (angiotensin receptor blocker) on central aortic pressures, in elderly patients (aged ≥60 years) with systolic hypertension and pulse pressure >60 mm Hg, indicative of arterial stiffness. Patients (n=454; mean age, 67.7 years; mean seated systolic blood pressure, 158.6 mm Hg; mean seated pulse pressure, 69.7 mm Hg) were randomized to receive once-daily sacubitril/valsartan 200 mg or olmesartan 20 mg, force titrated to double the initial doses after 4 weeks, before primary assessment at 12 weeks. The study extended double-blind treatment for 12 to 52 weeks, during which amlodipine (2.5-5 mg) and subsequently hydrochlorothiazide (6.25-25 mg) were added-on for patients not achieving blood pressure target (secondary assessments at week 12 (central aortic pulse pressure, -2.4 mm Hg, P blood pressure and central aortic systolic pressure, -4.1 mm Hg and -3.6 mm Hg, respectively, both P blood pressure parameters were similar between treatments ( P hypertension and stiff arteries. © 2017 American Heart Association, Inc.

Changes in myocardial fluid filtration are reflected in epicardial lymph pressure

NARCIS (Netherlands)

VanTeeffelen, J. W.; Merkus, D.; Vergroesen, I.; Spaan, J. A.

1997-01-01

The effect of increased fluid filtration on stopped-flow epicardial lymph pressure (P(lymph)), used as an indicator of myocardial interstitial volume, was investigated in the anesthetized open-chest dog. Histamine infusion resulted in an increased systolic peak in the P(lymph) signal together with

Mozart, but not the Beatles, reduces systolic blood pressure in patients with myocardial infarction.

Science.gov (United States)

Gruhlke, Luiza Carolina; Patrício, Marcelo Coelho; Moreira, Daniel Medeiros

2015-12-01

Music reduces systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) in various clinical situations, but it is unclear whether these changes occur in post-infarction patients. The aim is to evaluate the effects of music on patients with acute myocardial infarction (MI). We evaluated patients with MI and we measured SBP, DBP, HR and double product (DP) two times before the intervention and one time every fifteen minutes with an ambulatory blood pressure monitor. We divided the patients into 3 groups: a group listening to music by Mozart; another listening to a Beatles collection and a third one listening to the radio news. Outcomes were the change in mean SBP, DBP, HR and DP with intervention. We enrolled 60 patients (20 in each group). SBP was significantly reduced in the Mozart group (variation of –7.2 ± 8.5 mmHg) compared to the Beatles group (–1.3 ± 6.2 mmHg) (P = 0.021) and the radio news group (0.6 ± 8.7 mmHg) (P = 0.003). DP was significantly reduced in the Mozart group compared with the News group (–668.5 ± 773.2 vs 31.6 ± 722.1 mmHg) (P = 0.006). There were no differences in DBP and HR. Patients with MI who listened Mozart had a reduction in SBP and DP compared to those who listened to the Beatles or the news.

Melodic algorithms for pulse oximetry to allow audible discrimination of abnormal systolic blood pressures.

Science.gov (United States)

Chima, Ranjit S; Ortega, Rafael; Connor, Christopher W

2014-12-01

An anesthesiologist must remain vigilant of the patient's clinical status, incorporating many independent physiological measurements. Oxygen saturation and heart rate are represented by continuous audible tones generated by the pulse oximeter, a mandated monitoring device. Other important clinical parameters--notably blood pressure--lack any audible representation beyond arbitrarily-configured threshold alarms. Attempts to introduce further continuous audible tones have apparently foundered; the complexity and interaction of these tones have exceeded the ability of clinicians to interpret them. Instead, we manipulate the tonal and rhythmic structure of the accepted pulse oximeter tone pattern melodically. Three melodic algorithms were developed to apply tonal and rhythmic variations to the continuous pulse oximeter tone, dependent on the systolic blood pressure. The algorithms distort the original audible pattern minimally, to facilitate comprehension of both the underlying pattern and the applied variations. A panel of anesthesia practitioners (attending anesthesiologists, residents and nurse anesthetists) assessed these algorithms in characterizing perturbations in cardiopulmonary status. Twelve scenarios, incorporating combinations of oxygen desaturation, bradycardia, tachycardia, hypotension and hypertension, were tested. A rhythmic variation in which additional auditory information was conveyed only at halftime intervals, with every other "beat" of the pulse oximeter, was strongly favored. The respondents also strongly favored the use of musical chords over single tones. Given three algorithms of tones embedded in the pulse oximeter signal, anesthesiologists preferred a melodic tone to signal a significant change in blood pressure.

Changes with age in left ventricular function and volumes at rest and postexercise in postmenopausal women

International Nuclear Information System (INIS)

Yamada, Kiyoyasu; Isobe, Satoshi; Hirai, Makoto

2006-01-01

In postmenopausal women, it has been reported that the plasma estrogen levels diminish immediately after menopause, and that this phenomenon affects left ventricular (LV) function and volumes. However, the effects of age on LV function and volumes for a relatively short period in the postmenopausal women remain to be established. Electrocardiographically gated-myocardial single-photon emission computed tomography (SPECT) has recently provided accurate estimations of perfusion, cardiac systolic and diastolic functions. We investigated the age-related changes in LV function and volumes in postmenopausal women using electrocardiographically gated-myocardial scintigraphy. Twenty-two consecutive healthy postmenopausal women (mean age of 63.8±9.4 years, from 42 to 77 years) without cardiac disease underwent stress/rest technetium-99m tetrofosmin gated-myocardial SPECT with 16 frames per cardiac cycle at baseline and follow-up (1.0±0.3 years later). LV ejection fraction (LVEF) and LV volumes were calculated by quantitative gated SPECT (QGS) software. Fourier series were retained for the analysis of the volume curve. From this volume curve, we derived the following diastolic indices: peak filling rate (PFR) and time to PFR (TPFR). End-systolic volume index (ESVI) significantly decreased at postexercise (p=0.02) and tended to decrease at rest (p=0.06) from the baseline to the follow-up study. LVEF significantly increased at both postexercise (p=0.01) and rest (p=0.03) from the baseline to the follow-up study. The TPFR at rest tended to be prolonged from the baseline to the follow-up study (p=0.07). The absolute increase in LVEF at postexercise tended to decrease with age [4.8% (50s) vs. 3.4% (60s) vs. 1.2% (70s)]. An age-related change in cardiac performance is apparent at an approximately 1 year follow-up in postmenopausal women. In particular, the increase in LV systolic function tends to show the greatest value in the 50s subjects among the 3 generations. (author)

Effect of tender coconut water on systolic and diastolic blood pressure in prehypertensive women

Directory of Open Access Journals (Sweden)

Farapti Farapti

2014-02-01

. Dietary intakes of high potassium will decrease blood pressure (BP. Tender coconut water (TCW is a typical drink high in potassium. This study aimed to investigate the effect of TCW on BP in female teachers and employees prehypertension. Methods: The research was a parallel single blind randomized clinical trial. A total of 32 female prehypertension subjects aged 25-44 years. The subjects were selected using certain criteria and randomly allocated to one of two groups using block randomized, 16 subjects each. The treatment group received TCW 300 ml twice daily for 14 days and nutritional counseling, and the control group received water 300 ml twice daily for 14 days and nutritional counseling. Assessment of BP was done on day 0, day 8, and day 15. Statistical analysis were done using t-test and Mann-Whitney test. Results: Mean dietary intakes of potassium were 1420.28±405.54 mg/day or 30.22±8.63% compared to Recommended Dietary Allowance (RDA. During treatment period, potassium intake increased significantly in the treatment group. There were decreased BP in both groups, which were greater in the treatment group, but not statistically significant different (P > 0.05. The mean decrease of systolic BP was significant in treatment group (P = 0.031, meanwhile the mean decrease of diastolic BP was not significant (P=0.134. Conclusion: Tender coconut water 300 ml twice daily for 14 consecutive days has tendency to decrease systolic BP, but not diastolic blood pressure. (Health Science Indones 2013;2: 64-8Key words: coconut water, systolic and diastolic blood pressure

Evaluation of left ventricular function and volumes in patients with ischaemic cardiomyopathy: gated single-photon emission computed tomography versus two-dimensional echocardiography

International Nuclear Information System (INIS)

Vourvouri, E.C.; Poldermans, D.; Sianos, G.; Sozzi, F.B.; Schinkel, A.F.L.; Sutter, J. de; Roelandt, J.R.T.C.; Bax, J.J.; Parcharidis, G.; Valkema, R.

2001-01-01

The objective of this study was to perform a head-to-head comparison between two-dimensional (2D) echocardiography and gated single-photon emission computed tomography (SPET) for the evaluation of left ventricular (LV) function and volumes in patients with severe ischaemic LV dysfunction. Thirty-two patients with chronic ischaemic LV dysfunction [mean LV ejection fraction (EF) 25%±6%] were studied with gated SPET and 2D echocardiography. Regional wall motion was evaluated by both modalities and scored by two independent observers using a 16-segment model with a 5-point scoring system (1= normokinesia, 2= mild hypokinesia, 3= severe hypokinesia, 4= akinesia and 5= dyskinesia). LVEF and LV end-diastolic and end-systolic volumes were evaluated by 2D echocardiography using the Simpson's biplane discs method. The same parameters were calculated using quantitative gated SPET software (QGS, Cedars-Sinai Medical Center). The overall agreement between the two imaging modalities for assessment of regional wall motion was 69%. The correlations between gated SPET and 2D echocardiography for the assessment of end-diastolic and end-systolic volumes were excellent (r=0.94, P<0.01, and r=0.96, P<0.01, respectively). The correlation for LVEF was also good (r=0.83, P<0.01). In conclusion: in patients with ischaemic cardiomyopathy, close and significant relations between gated SPET and 2D echocardiography were observed for the assessment of regional and global LV function and LV volumes; gated SPET has the advantage that it provides information on both LV function/dimensions and perfusion. (orig.)

Home blood pressure measurement in elderly patients with cognitive impairment: comparison of agreement between relative-measured blood pressure and automated blood pressure measurement.

Science.gov (United States)

Plichart, Matthieu; Seux, Marie-Laure; Caillard, Laure; Chaussade, Edouard; Vidal, Jean-Sébastien; Boully, Clémence; Hanon, Olivier

2013-08-01

Home blood pressure measurement (HBPM) is recommended by guidelines for hypertension management. However, this method might be difficult to use in elderly individuals with cognitive disorders. Our aim was to assess the agreement and the feasibility of HBPM by a relative as compared with 24-h ambulatory blood pressure monitoring (ABPM) in elderly patients with dementia. Sixty outpatients with dementia aged 75 years and older with office hypertension (≥140/90 mmHg) were subjected successively to HBPM by a trained relative and 24-h ABPM. The order of the two methods was randomized. Current guidelines' thresholds for the diagnosis of hypertension were used. The mean (SD) age of the patients was 80.8 (6.1) years (55% women) and the mean (SD) mini-mental state examination score was 20.1 (6.9). The feasibility of relative-HBPM was very high, with a 97% success rate (defined by ≥12/18 measurements reported). The blood pressure measurements were highly correlated between the two methods (r=0.75 and 0.64 for systolic blood pressure and diastolic blood pressure, respectively; Pmethods for the diagnosis of sustained hypertension and white-coat hypertension was excellent (overall agreement, 92%; κ coefficient, 0.81; 95% CI, 0.61-0.93). Similar results were found for daytime-ABPM. In cognitively impaired elderly patients, HBPM by a relative using an automated device was a good alternative to 24-h ABPM.

The decrease of cardiac chamber volumes and output during positive-pressure ventilation

DEFF Research Database (Denmark)

Kristensen, Kasper Kyhl; Ahtarovski, Kiril Aleksov; Iversen, Kasper

2013-01-01

the effect of PPV on the central circulation by studying cardiac chamber volumes with cardiac magnetic resonance imaging (CMR). We hypothesized that PPV lowers cardiac output (CO) mainly via the Frank-Starling relationship. In 18 healthy volunteers, cardiac chamber volumes and flow in aorta and the pulmonary...... artery were measured by CMR during PPV levels of 0, 10, and 20 cmH2O applied via a respirator and a face mask. All cardiac chamber volumes decreased in proportion to the level of PPV. Following 20-cmH2O PPV, the total diastolic and systolic cardiac volumes (±SE) decreased from 605 (±29) ml to 446 (±29......) ml (P volume decreased by 27 (±4) ml/beat; heart rate increased by 7 (±2) beats/min; and CO decreased by 1.0 (±0.4) l/min (P

Effect of Spinal Manipulation of Upper Cervical Vertebrae on Blood Pressure: Results of a Pilot Sham-Controlled Trial.

Science.gov (United States)

Goertz, Christine M; Salsbury, Stacie A; Vining, Robert D; Long, Cynthia R; Pohlman, Katherine A; Weeks, William B; Lamas, Gervasio A

2016-06-01

The purpose of this pilot sham-controlled clinical trial was to estimate the treatment effect and safety of toggle recoil spinal manipulation for blood pressure management. Fifty-one participants with prehypertension or stage 1 hypertension (systolic blood pressure ranging from 135 to 159 mm Hg or diastolic blood pressure ranging from 85 to 99 mm Hg) were allocated by an adaptive design to 2 treatments: toggle recoil spinal manipulation or a sham procedure. Participants were seen by a doctor of chiropractic twice weekly for 6 weeks and remained on their antihypertensive medications, as prescribed, throughout the trial. Blood pressure was assessed at baseline and after study visits 1, 6 (week 3), and 12 (week 6), with the primary end point at week 6. Analysis of covariance was used to compare mean blood pressure changes from baseline between groups at each end point, controlling for sex, age, body mass index, and baseline blood pressure. Adjusted mean change from baseline to week 6 was greater in the sham group (systolic, -4.2 mm Hg; diastolic, -1.6 mm Hg) than in the spinal manipulation group (systolic, 0.6 mm Hg; diastolic, 0.7 mm Hg), but the difference was not statistically significant. No serious and few adverse events were noted. Six weeks of toggle recoil spinal manipulation did not lower systolic or diastolic blood pressure when compared with a sham procedure. No serious adverse events from either treatment were reported. Our results do not support a larger clinical trial. Further research to understand the potential mechanisms of action involving upper cervical manipulation on blood pressure is warranted before additional clinical investigations are conducted. Copyright © 2016. Published by Elsevier Inc.

Alveolar Tidal recruitment/derecruitment and Overdistension During Four Levels of End-Expiratory Pressure with Protective Tidal Volume During Anesthesia in a Murine Lung-Healthy Model.

Science.gov (United States)

Soares, Joao Henrique Neves; Carvalho, Alysson Roncally; Bergamini, Bruno Curty; Gress, Maria Alice Kuster; Jandre, Frederico Caetano; Zin, Walter Araujo; Giannella-Neto, Antonio

2018-06-01

We compared respiratory mechanics between the positive end-expiratory pressure of minimal respiratory system elastance (PEEP minErs ) and three levels of PEEP during low-tidal-volume (6 mL/kg) ventilation in rats. Twenty-four rats were anesthetized, paralyzed, and mechanically ventilated. Airway pressure (P aw ), flow (F), and volume (V) were fitted by a linear single compartment model (LSCM) P aw (t) = E rs  × V(t) + R rs  × F(t) + PEEP or a volume- and flow-dependent SCM (VFDSCM) P aw (t) = (E 1  + E 2  × V(t)) × V(t) + (K 1  + K 2  × |F(t)|) × F(t) + PEEP, where E rs and R rs are respiratory system elastance and resistance, respectively; E 1 and E 2 × V are volume-independent and volume-dependent E rs , respectively; and K 1 and K 2  × F are flow-independent and flow-dependent R rs , respectively. Animals were ventilated for 1 h at PEEP 0 cmH 2 O (ZEEP); PEEP minErs ; 2 cmH 2 O above PEEP minErs (PEEP minErs+2 ); or 4 cmH 2 O above PEEP minErs (PEEP minErs+4 ). Alveolar tidal recruitment/derecruitment and overdistension were assessed by the index %E 2  = 100 × [(E 2  × V T )/(E 1  + |E 2 | × V T )], and alveolar stability by the slope of E rs (t). %E 2 varied between 0 and 30% at PEEP minErs in most respiratory cycles. Alveolar Tidal recruitment/derecruitment (%E 2   30) were predominant in the absence of PEEP and in PEEP levels higher than PEEP minErs , respectively. The slope of E rs (t) was different from zero in all groups besides PEEP minErs+4 . PEEP minErs presented the best compromise between alveolar tidal recruitment/derecruitment and overdistension, during 1 h of low-V T mechanical ventilation.

Slow loaded breathing training improves blood pressure, lung capacity and arm exercise endurance for older people with treated and stable isolated systolic hypertension.

Science.gov (United States)

Ublosakka-Jones, Chulee; Tongdee, Phailin; Pachirat, Orathai; Jones, David A

2018-03-28

Hypertension and reduced lung function are important features of aging. Slow loaded breathing training reduces resting blood pressure and the question is whether this can also improve lung function. Thirty-two people (67 ± 5 years, 16 male) with controlled isolated systolic hypertension undertook an eight weeks randomised controlled training trial with an inspiratory load of 25% maximum inspiratory pressure (MIP) at 6 breaths per minute (slow loaded breathing; SLB) or deep breathing control (CON). Outcome measures were resting blood pressure (BP) and heart rate; MIP; lung capacity; chest and abdominal expansion; arm cranking exercise endurance at 50% heart rate reserve. Home based measurement of resting systolic BP decreased by 20 mm Hg (15 to 25) (Mean and 95%CI) for SLB and by 5 mm Hg (1 to 7) for CON. Heart rate and diastolic BP also decreased significantly for SLB but not CON. MIP increased by 15.8 cm H 2 O (11.8 to 19.8) and slow vital capacity by 0.21 L (0.15 to 0.27) for SLB but not for CON. Chest and abdominal expansion increased by 2.3 cm (2.05 to 2.55) and 2.5 cm (2.15 to 2.85), respectively for SLB and by 0.5 cm (0.26 to 0.74) and 1.7 cm (1.32 to 2.08) for CON. Arm exercise time increased by 4.9 min (3.65 to 5.15) for SLB with no significant change for CON. Slow inspiratory muscle training is not only effective in reducing resting BP, even in older people with well controlled isolated systolic hypertension but also increases inspiratory muscle strength, lung capacity and arm exercise duration. Copyright © 2018. Published by Elsevier Inc.

Systolic ventricular filling.

Science.gov (United States)

Torrent-Guasp, Francisco; Kocica, Mladen J; Corno, Antonio; Komeda, Masashi; Cox, James; Flotats, A; Ballester-Rodes, Manel; Carreras-Costa, Francesc

2004-03-01

The evidence of the ventricular myocardial band (VMB) has revealed unavoidable coherence and mutual coupling of form and function in the ventricular myocardium, making it possible to understand the principles governing electrical, mechanical and energetical events within the human heart. From the earliest Erasistratus' observations, principal mechanisms responsible for the ventricular filling have still remained obscured. Contemporary experimental and clinical investigations unequivocally support the attitude that only powerful suction force, developed by the normal ventricles, would be able to produce an efficient filling of the ventricular cavities. The true origin and the precise time frame for generating such force are still controversial. Elastic recoil and muscular contraction were the most commonly mentioned, but yet, still not clearly explained mechanisms involved in the ventricular suction. Classical concepts about timing of successive mechanical events during the cardiac cycle, also do not offer understandable insight into the mechanism of the ventricular filling. The net result is the current state of insufficient knowledge of systolic and particularly diastolic function of normal and diseased heart. Here we summarize experimental evidence and theoretical backgrounds, which could be useful in understanding the phenomenon of the ventricular filling. Anatomy of the VMB, and recent proofs for its segmental electrical and mechanical activation, undoubtedly indicates that ventricular filling is the consequence of an active muscular contraction. Contraction of the ascendent segment of the VMB, with simultaneous shortening and rectifying of its fibers, produces the paradoxical increase of the ventricular volume and lengthening of its long axis. Specific spatial arrangement of the ascendent segment fibers, their interaction with adjacent descendent segment fibers, elastic elements and intra-cavitary blood volume (hemoskeleton), explain the physical principles

Intraventricular dyssynchrony in light chain amyloidosis: a new mechanism of systolic dysfunction assessed by 3-dimensional echocardiography

Directory of Open Access Journals (Sweden)

Truran Seth

2008-08-01

Full Text Available Abstract Background Light chain amyloidosis (AL is a rare but often fatal disease due to intractable heart failure. Amyloid deposition leads to diastolic dysfunction and often preserved ejection fraction. We hypothesize that AL is associated with regional systolic dyssynchrony. The aim is to compare left ventricular (LV regional synchrony in AL subjects versus healthy controls using 16-segment dyssynchrony index measured from 3-dimension-al (3D echocardiography. Methods Cardiac 3D echocardiography full volumes were acquired in 10 biopsy-proven AL subjects (60 ± 3 years, 5 females and 10 healthy controls (52 ± 1 years, 5 females. The LV was subdivided into 16 segments and the time from end-diastole to the minimal systolic volume for each of the 16 segments was expressed as a percent of the cycle length. The standard deviations of these times provided a 16-segment dyssynchrony index (16-SD%. 16-SD% was compared between healthy and AL subjects. Results Left ventricular ejection fraction was comparable (control vs. AL: 62.4 ± 0.6 vs. 58.6 ± 2.8%, p = NS. 16-SD% was significantly higher in AL versus healthy subjects (5.93 ± 4.4 vs. 1.67 ± 0.87%, p = 0.003. 16-SD% correlated with left ventricular mass index (R 0.45, p = 0.04 but not to left ventricular ejection fraction. Conclusion Light chain amyloidosis is associated with left ventricular regional systolic dyssynchrony. Regional dyssynchrony may be an unrecognized mechanism of heart failure in AL subjects.

Power loss and right ventricular efficiency in patients after tetralogy of Fallot repair with pulmonary insufficiency: clinical implications.

Science.gov (United States)

Fogel, Mark A; Sundareswaran, Kartik S; de Zelicourt, Diane; Dasi, Lakshmi P; Pawlowski, Tom; Rome, Jack; Yoganathan, Ajit P

2012-06-01

To quantify right ventricular output power and efficiency and correlate these to ventricular function in patients with repaired tetralogy of Fallot. This might aid in determining the optimal timing for pulmonary valve replacement. We reviewed the cardiac catheterization and magnetic resonance imaging data of 13 patients with tetralogy of Fallot (age, 22 ± 17 years). Using pressure and flow measurements in the main pulmonary artery, cardiac output and regurgitation fraction, right ventricular (RV) power output, loss, and efficiency were calculated. The RV function was evaluated using cardiac magnetic resonance imaging. The RV systolic power was 1.08 ± 0.62 W, with 20.3% ± 8.6% power loss owing to 41% ± 14% pulmonary regurgitation (efficiency, 79.7% ± 8.6%; 0.84 ± 0.73 W), resulting in a net cardiac output of 4.24 ± 1.82 L/min. Power loss correlated significantly with the indexed RV end-diastolic and end-systolic volume (R = 0.78, P = .002 and R = 0.69, P = .009, respectively). The normalized RV power output had a significant negative correlation with RV end-diastolic and end-systolic volumes (both R = -0.87, P = .002 and R = -0.68, P = .023, respectively). A rapid decrease occurred in the RV power capacity with an increasing RV volume, with the curve flattening out at an indexed RV end-diastolic and end-systolic volume threshold of 139 mL/m(2) and 75 mL/m(2), respectively. Significant power loss is present in patients with repaired tetralogy of Fallot and pulmonary regurgitation. A rapid decrease in efficiency occurs with increasing RV volume, suggesting that pulmonary valve replacement should be done before the critical value of 139 mL/m(2) and 75 mL/m(2) for the RV end-diastolic and end-systolic volume, respectively, to preserve RV function. Copyright © 2012 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Global end-diastolic volume an emerging preload marker vis-a-vis other markers - Have we reached our goal?

Directory of Open Access Journals (Sweden)

P M Kapoor

2016-01-01

Full Text Available A reliable estimation of cardiac preload is helpful in the management of severe circulatory dysfunction. The estimation of cardiac preload has evolved from nuclear angiography, pulmonary artery catheterization to echocardiography, and transpulmonary thermodilution (TPTD. Global end-diastolic volume (GEDV is the combined end-diastolic volumes of all the four cardiac chambers. GEDV has been demonstrated to be a reliable preload marker in comparison with traditionally used pulmonary artery catheter-derived pressure preload parameters. Recently, a new TPTD system called EV1000™ has been developed and introduced into the expanding field of advanced hemodynamic monitoring. GEDV has emerged as a better preload marker than its previous conventional counterparts. The advantage of it being measured by minimum invasive methods such as PiCCO™ and newly developed EV1000™ system makes it a promising bedside advanced hemodynamic parameter.

Noninvasive arterial blood pressure waveforms in patients with continuous-flow left ventricular assist devices.

Science.gov (United States)

Martina, Jerson R; Westerhof, Berend E; de Jonge, Nicolaas; van Goudoever, Jeroen; Westers, Paul; Chamuleau, Steven; van Dijk, Diederik; Rodermans, Ben F M; de Mol, Bas A J M; Lahpor, Jaap R

2014-01-01

Arterial blood pressure and echocardiography may provide useful physiological information regarding cardiac support in patients with continuous-flow left ventricular assist devices (cf-LVADs). We investigated the accuracy and characteristics of noninvasive blood pressure during cf-LVAD support. Noninvasive arterial pressure waveforms were recorded with Nexfin (BMEYE, Amsterdam, The Netherlands). First, these measurements were validated simultaneously with invasive arterial pressures in 29 intensive care unit patients. Next, the association between blood pressure responses and measures derived by echocardiography, including left ventricular end-diastolic dimensions (LVEDDs), left ventricular end-systolic dimensions (LVESDs), and left ventricular shortening fraction (LVSF) were determined during pump speed change procedures in 30 outpatients. Noninvasive arterial blood pressure waveforms by the Nexfin monitor slightly underestimated invasive measures during cf-LVAD support. Differences between noninvasive and invasive measures (mean ± SD) of systolic, diastolic, mean, and pulse pressures were -7.6 ± 5.8, -7.0 ± 5.2, -6.9 ± 5.1, and -0.6 ± 4.5 mm Hg, respectively (all blood pressure responses did not correlate with LVEDD, LVESD, or LVSF, while LVSF correlated weakly with both pulse pressure (r = 0.24; p = 0.005) and (dP(art)/dt)max (r = 0.25; p = 0.004). The dicrotic notch in the pressure waveform was a better predictor of aortic valve opening (area under the curve [AUC] = 0.87) than pulse pressure (AUC = 0.64) and (dP(art)/dt)max (AUC = 0.61). Patients with partial support rather than full support at 9,000 rpm had a significant change in systolic pressure, pulse pressure, and (dP(art)/dt)max during ramp studies, while echocardiographic measures did not change. Blood pressure measurements by Nexfin were reliable and may thereby act as a compliment to the assessment of the cf-LVAD patient.

Cyclooxygenase-2-dependent prostacyclin formation and blood pressure homeostasis: targeted exchange of cyclooxygenase isoforms in mice

DEFF Research Database (Denmark)

Yu, Ying; Stubbe, Jane; Ibrahim, Salam

2010-01-01

pressure. OBJECTIVE: To elucidate the role of COX-2 in blood pressure homeostasis using COX-1>COX-2 mice, in which the COX-1 expression is controlled by COX-2 regulatory elements. METHODS AND RESULTS: COX-1>COX-2 mice developed systolic hypertension relative to wild types (WTs) on a high-salt diet (HSD...... and again the increase in formation of PGI(2) observed in WTs was suppressed in cells derived from both mutants. Intramedullary infusion of the PGI(2) receptor agonist increased urine volume and sodium excretion in mice. CONCLUSIONS: These studies suggest that dysregulated expression of the COX-2 dependent...

Low pulmonary artery flush perfusion pressure combined with high positive end-expiratory pressure reduces oedema formation in isolated porcine lungs

International Nuclear Information System (INIS)

Schumann, Stefan; Schließmann, Stephan J; Wagner, Giskard; Goebel, Ulrich; Priebe, Hans-Joachim; Guttmann, Josef; Kirschbaum, Andreas

2010-01-01

Flush perfusion of the pulmonary artery with organ protection solution is a standard procedure before lung explantation. However, rapid flush perfusion may cause pulmonary oedema which is deleterious in the lung transplantation setting. In this study we tested the hypotheses that high pulmonary perfusion pressure contributes to the development of pulmonary oedema and positive end-expiratory pressure (PEEP) counteracts oedema formation. We expected oedema formation to increase weight and decrease compliance of the lungs on the basis of a decrease in alveolar volume as fluid replaces alveolar air spaces. The pulmonary artery of 28 isolated porcine lungs was perfused with a low-potassium dextrane solution at low (mean 27 mmHg) or high (mean 40 mmHg) pulmonary artery pressure (PAP) during mechanical ventilation at low (4 cmH 2 O) or high (8 cmH 2 O) PEEP, respectively. Following perfusion and storage, relative increases in lung weight were smaller (p < 0.05) during perfusion at low PAP (62 ± 32% and 42 ± 26%, respectively) compared to perfusion at high PAP (133 ± 54% and 87 ± 30%, respectively). Compared to all other PAP–PEEP combinations, increases in lung weight were smallest (44 ± 9% and 27 ± 12%, respectively), nonlinear intratidal lung compliance was largest (46% and 17% respectively, both p < 0.05) and lung histology showed least infiltration of mononuclear cells in the alveolar septa, and least alveolar destruction during the combination of low perfusion pressure and high PEEP. The findings suggest that oedema formation during pulmonary artery flush perfusion in isolated and ventilated lungs can be reduced by choosing low perfusion pressure and high PEEP. PAP–PEEP titration to minimize pulmonary oedema should be based on lung mechanics and PAP monitoring

Relationship of central and peripheral blood pressure to left ventricular mass in hypertensive patients.

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Pérez-Lahiguera, Francisco J; Rodilla, Enrique; Costa, Jose A; Gonzalez, Carmen; Martín, Joaquin; Pascual, Jose M

2012-12-01

The purpose of the present study was to assess the relationship of central and peripheral blood pressure to left ventricular mass. Cross-sectional study that included 392 never treated hypertensive individuals. Measurement of office, 24-h ambulatory, and central blood pressure (obtained using applanation tonometry) and determination of left ventricular mass by echocardiography were performed in all patients. In a multiple regression analysis, with adjustment for age, gender and metabolic syndrome, 24-h blood pressure was more closely related to ventricular mass than the respective office and central blood pressures. Systolic blood pressures always exhibited a higher correlation than diastolic blood pressures in all 3 determinations. The correlation between left ventricular mass index and 24-h systolic blood pressure was higher than that of office (P<.002) or central systolic blood pressures (P<.002). Changes in 24-h systolic blood pressure caused the greatest variations in left ventricular mass index (P<.001). In our population of untreated middle-aged hypertensive patients, left ventricular mass index is more closely related to 24-h ambulatory blood pressure than to office or central blood pressure. Central blood pressure does not enable us to better identify patients with left ventricular hypertrophy. Copyright © 2012 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

[Effects of acupuncture on circadian rhythm of blood pressure in patients with essential hypertension].

Science.gov (United States)

Lei, Yun; Jin, Jiu; Ban, Haipeng; Du, Yuzheng

2017-11-12

To observe the effects of acupuncture combined with medication on circadian rhythm of blood pressure in patients with essential hypertension. Sixty-four patients of essential hypertension were randomly divided into an observation group and a control group, 32 cases in each group. All the patients maintained original treatment (taking antihypertensive medication); the patients in the observation group were treated with acupuncture method of " Huoxue Sanfeng , Shugan Jianpi ", once a day, five times per week, for totally 6 weeks (30 times). The circadian rhythm of blood pressure and related dynamic parameters were observed before and after treatment in the two groups. (1) The differences of daytime average systolic blood pressure (dASBP), daytime average diastolic blood pressure (dADBP), nighttime average systolic blood pressure (nASBP) and circadian rhythm of systolic blood pressure before and after treatment were significant in the observation group (all P circadian rhythm of blood pressure and related dynamic parameters before and after treatment were insignificant in the control group (all P >0.05). The nASBP and circadian rhythm of systolic blood pressure in the observation group were significantly different from those in the control group (all P circadian rhythm of blood pressure in the observation group was higher than that in the control group ( P circadian rhythm of blood pressure and related dynamic parameters in patients with essential hypertension.

The usefulness of contrast during exercise echocardiography for the assessment of systolic pulmonary pressure

Directory of Open Access Journals (Sweden)

Cordeiro Ana

2008-10-01

Full Text Available Abstract Background The systolic pulmonary artery pressure (PAPs can be accurately estimated, non-invasively, using continuous-wave Doppler (CWD ultrasound measurement of the peak velocity of a tricuspid regurgitant (TR jet. However, it is often difficult to obtain adequate tricuspid regurgitation signals for measurement of PAPs, what could lead to its underestimation. Therefore, utilization of air-blood-saline contrast has been implemented for the improvement of Doppler signal in several clinical contexts. It is now recommended in the evaluation of patients with pulmonary hypertension. Physical activity is severely restricted in patients with PAH, being exertional dypnea the most typical symptom. Exercise stress echo-Doppler imaging allows assessment of the response to exercise. It is an excellent screening test for patients with suspected PAH. Our purpose was to evaluate the value and accuracy of agitated saline with blood contrast echocardiography, in the improvement of the Doppler signal, to quantify PAPs during treadmill exercise-echocardiography. Purpose To evaluate the value of contrast echocardiography, using agitated saline with blood, in the improvement of the Doppler signal used to quantify the pulmonary artery systolic pressure during exercise. Methods From a total of 41 patients (pts, we studied 38 pts (93%, 35 women, aged 54 ± 12 years-old. 27 with the diagnosis of systemic sclerosis, 10 with history of pulmonary embolism and one patient with a suspected idiopathic PAH, who were referred to the Unity of Heart Failure and Pulmonary Hypertension for screening of PAH. According to the Unity protocol, a transthoracic echocardiogram was made, in left decubitus (LD, with evaluation of right ventricle-right atria gradient (RV/RAg. A peripheral venous access was obtained, with a 3-way stopcock and the patients were placed in orthostatism (O, with a new evaluation of RV/RAg. Exercise echocardiography (EE was begun, with evaluation of RV

Evaluation of left ventricular function and volume with multidetector-row computed tomography. Comparison with electrocardiogram-gated single photon emission computed tomography

International Nuclear Information System (INIS)

Suzuki, Takeya; Yamashina, Shohei; Nanjou, Shuji; Yamazaki, Junichi

2007-01-01

This study compared left ventricular systolic function and volume determined by multidetector-row computed tomography (MDCT) and electrocardiogram-gated single photon emission computed tomography (G-SPECT) Thirty-seven patients with coronary artery disease and non-cardiovascular disease underwent MDCT. In this study, left ventricular ejection fraction (EF), left ventricular end-diastolic volume (EDV) and left ventricular end-systolic volume (ESV) were calculated using only two-phase imaging with MDCT. Left ventricular function and volume were compared using measurements from G-SPECT. We conducted MDCT and G-SPECT virtually simultaneously. Both the EF and ESV evaluated by MDCT closely correlated with G-SPECT (r=0.763, P 65 bpm) during MDCT significantly influenced the difference in EF calculated from MDCT and G-SPECT (P<0.05). Left ventricular function can be measured with MDCT as well as G-SPECT. However, a heart rate over 65 bpm during MDCT negatively affects the EF correlation between MDCT and G-SPECT. (author)

Recommended reference materials for realization of physicochemical properties pressure-volume-temperature relationships

CERN Document Server

Herington, E F G

1977-01-01

Recommended Reference Materials for Realization of Physicochemical Properties presents recommendations of reference materials for use in measurements involving physicochemical properties, namely, vapor pressure; liquid-vapor critical temperature and critical pressure; orthobaric volumes of liquid and vapor; pressure-volume-temperature properties of the unsaturated vapor or gas; and pressure-volume-temperature properties of the compressed liquid. This monograph focuses on reference materials for vapor pressures at temperatures up to 770 K, as well as critical temperatures and critical pressures

The effect of endogenously released glucose, insulin, glucagon-like peptide 1, ghrelin on cardiac output, heart rate, stroke volume, and blood pressure.

Science.gov (United States)

Hlebowicz, Joanna; Lindstedt, Sandra; Björgell, Ola; Dencker, Magnus

2011-12-29

Ingestion of a meal increases the blood flow to the gastrointestinal organs and affects the heart rate (HR), blood pressure and cardiac output (CO), although the mechanisms are not known. The aim of this study was to evaluate the effect of endogenously released glucose, insulin, glucagon-like peptide 1 (GLP-1), ghrelin on CO, HR, stroke volume (SV), and blood pressure. Eleven healthy men and twelve healthy women ((mean ± SEM) aged: 26 ± 0.2 y; body mass index: 21.8 ± 0.1 kg/m(2))) were included in this study. The CO, HR, SV, systolic and diastolic blood pressure, antral area, gastric emptying rate, and glucose, insulin, GLP-1 and ghrelin levels were measured. The CO and SV at 30 min were significantly higher, and the diastolic blood pressure was significantly lower, than the fasting in both men and women (P blood pressure (P = 0.021, r = -0.681), and the change in SV (P = 0.008, r = -0.748) relative to the fasting in men. The insulin 0-30 min AUC was significantly correlated to the CO 0-30 min AUC (P = 0.002, r = 0.814) in men. Significant correlations were also found between the 0-120 min ghrelin and HR AUCs (P = 0.007, r = 0.966) in men. No statistically significant correlations were seen in women. Physiological changes in the levels of glucose, insulin, GLP-1 and ghrelin may influence the activity of the heart and the blood pressure. There may also be gender-related differences in the haemodynamic responses to postprandial changes in hormone levels. The results of this study show that subjects should not eat immediately prior to, or during, the evaluation of cardiovascular interventions as postprandial affects may affect the results, leading to erroneous interpretation of the cardiovascular effects of the primary intervention. NCT01027507.

Errors during MRT measurements of the left ventricular volume using a multi-slice technique

International Nuclear Information System (INIS)

Pitton, M.B.; Just, M.; Grebe, P.; Kreitner, K.F.; Erbel, R.; Thelen, M.

1992-01-01

A multi-slice technique for MRT measurements of the left ventricular volume is much faster than the use of single-slice methods and is therefore better tolerated, leaving time for additional measurements. The end-diastolic left ventricular volume can be reliably measured by this method (123.3±13.5 ml vs. 124.1±ml). The end-systolic volume is consistently overestimated by 23.7±18,3% compared with the reference value obtained by single slice measurements (47.9±8.9 ml vs 39.1±7.9 ml). Correspondingly, stroke volume and ejection fraction is underestimated on average by 10.6±9.7% and 10.6±7.6% respectively). (orig.) [de

A new dynamic myocardial phantom for evaluation of SPECT and PET quantitation in systolic and diastolic conditions

International Nuclear Information System (INIS)

Dreuille, O. de; Bendriem, B.; Riddell, C.

1996-01-01

We present a new dynamic myocardial phantom designed to evaluate SPECT and PET imaging in systolic and diastolic conditions. The phantom includes a thoracic attenuating media and the myocardial wall thickness varying during the scan can be performed. In this study the phantom was used with three different wall thickness characteristic of a systolic, end-diastolic and pathologic end-diastolic condition. The myocardium was filled with 99m Tc, 18 F and Gd and imaged by SPECT, PET and MRI. SPECT attenuation correction was performed using a modified PET transmission. A bull's eyes image was obtained for all data and wall ROI were then drawn for analysis. Using MRI as a reference, error from PET, SPECT and attenuation corrected SPECT were calculated. Systolic PET performances agree with MRI. Quantitation loss due to wall thickness reduction compared to the systole. Attenuation correction in SPECT leads to significant decrease of the error both in systole (from 29% to 14%) and diastole (35% to 22%). This is particularly sensitive for septum and inferior walls. SPECT residual errors (14% in systole and 22% in pathologic end-diastole) are likely caused by scatter, noise and depth dependent resolution effect. The results obtained with this dynamical phantom demonstrate the quantitation improvement achieved in SPECT with attenuation correction and also reinforce the need for variable resolution correction in addition to attenuation correction

Body size at birth and blood pressure among children in developing countries.

Science.gov (United States)

Law, C M; Egger, P; Dada, O; Delgado, H; Kylberg, E; Lavin, P; Tang, G H; von Hertzen, H; Shiell, A W; Barker, D J

2001-02-01

Studies in developed countries have shown that reduced fetal growth is related to raised blood pressure in childhood and adult life. Little is known about this association in developing countries, where fetal growth retardation is common. In 1994-1995, we measured blood pressure in 1570 3-6-year-old children living in China, Guatemala, Chile, Nigeria and Sweden. We related their blood pressure to patterns of fetal growth, as measured by body proportions at birth. The children were all born after 37 weeks gestation and weighed more than 2.5 kg at birth. In each country, blood pressure was positively related to the child's current weight. After adjusting for this and gender, systolic pressure was inversely related to size at birth in all countries except Nigeria. In Chile, China and Guatemala, children who were proportionately small at birth had raised systolic pressure. For example, in Chile, systolic pressure adjusted for current weight increased by 4.9 mmHg (95% CI : 2.1, 7.7) for every kilogram decrease in birthweight, by 1 mmHg (95% CI : 0.4, 1.6) for every centimetre decrease in birth length, and by 1.3 mmHg (95% CI : 0.4, 2.2) for every centimetre decrease in head circumference at birth. In Sweden, systolic pressure was higher in children who were disproportionately small, that is thin, at birth. Systolic pressure increased by 0.3 mmHg (95% CI : 0.0, 0.6) for every unit (kg/m3) decrease in ponderal index at birth. These associations were independent of the duration of gestation. Raised blood pressure among children in three samples from China, Central and South America is related to proportionate reduction in body size at birth, which results from reduced growth throughout gestation. The relation between fetal growth and blood pressure may be different in African populations. Proportionately reduced fetal growth is the prevalent pattern of fetal growth retardation in developing countries, and is associated with chronic undernutrition among women. Improvement

ECG-gated blood pool tomography in the determination of left ventricular volume, ejection fraction, and wall motion

International Nuclear Information System (INIS)

Underwood, S.R.; Ell, P.J.; Jarritt, P.H.; Emanuel, R.W.; Swanton, R.H.

1984-01-01

ECG-gated blood pool tomography promises to provide a ''gold standard'' for noninvasive measurement of left ventricular volume, ejection fraction, and wall motion. This study compares these measurements with those from planar radionuclide imaging and contrast ventriculography. End diastolic and end systolic blood pool images were acquired tomographically using an IGE400A rotating gamma camera and Star computer, and slices were reconstructed orthogonal to the long axis of the heart. Left ventricular volume was determined by summing the areas of the slices, and wall motion was determined by comparison of end diastolic and end systolic contours. In phantom experiments this provided an accurate measurement of volume (r=0.98). In 32 subjects who were either normal or who had coronary artery disease left ventricular volume (r=0.83) and ejection fraction (r=0.89) correlated well with those using a counts based planar technique. In 16 of 18 subjects who underwent right anterior oblique X-ray contrast ventriculography, tomographic wall motion agreed for anterior, apical, and inferior walls, but abnormal septal motion which was not apparent by contrast ventriculography, was seen in 12 subjects tomographically. All 12 had disease of the left anterior descending coronary artery and might have been expected to have abnormal septal motion. ECG-gated blood pool tomography can thus determine left ventricular volume and ejection fraction accurately, and provides a global description of wall motion in a way that is not possible from any single planar image

Independent verification of tank volume measurements by pressure-volume authentication

International Nuclear Information System (INIS)

Suda, S.C.; Keisch, B.

1992-01-01

Brookhaven National Laboratory has developed a portable pressure-volume authenticator** as a standard and means of checking the functionality and quality of bubbler-probe volumetric devices. The pressure-volume authenticator (PVA) consists of an automated electromanometer system that is controlled by a laptop computer, and a transportable volumetric artifact. A portable pressure gage is connected, via a scanivalve, to the operator's bubbler-probe system and independently measures all bubbler probes. The transportable volumetric artifact is a one-meter high vessel equipped with bubble-probes, computer controlled air-purge rotameters, and platinum resistance (RTD) thermometer. High quality measurements are obtained by use of a fast sampling technique and sophisticated software developed under this program. The computer software performs the following functions: (a) instrument control, (b) data acquisition, (c) on-line graphical and numerical display of measurement data, and (d) detailed data analysis. The device also may provide hands-on training for inspectors and plant operators in high quality volumetric data collection and analysis. A field demonstration of the automated electromanometer system was conducted on the PETRA input accountancy tank, JRC-Ispra in November 1991

Volumes of virtual modifications and virtual polymorphous transformations in transition metals under pressure

International Nuclear Information System (INIS)

Zil'bershtejn, V.A.; Zaretskij, L.B.; Ehstrin, Eh.I.

1975-01-01

To find out what phases are likely to occur under pressure, it is necessary to know the relative density of various modifications, that is the ratio of the volumes of stable and virtual modifications and generally speaking the ratio of the phase compressibility. If the virtual phase volume is less than the volume of the stable phase, then such a phase is likely to appear under pressure. A method has been developed for computing the volumes of the virtual modifications from the data on the solid solutions lattice parameters. Testing the applicability of the method for a number of systems with a complete mutual solubility has shown, that the method proposed permits to estimate the volumes of the transition metals virtual modifications with the error probably not exceeding 1%. The analysis was made of the data available on the solid solutions of transition metals with fcc-, bcc- and hcp-lattices. The virtual volumes have been computed for hcp-iridium, hcp-rhodium, hcp-molybdenum, fcc-molybdenum, fcc-chromium, bcc-rhenium, bcc-ruthenium and bcc-technetium. The data obtained on the virtual modifications volumes permit to assume that the pressure increase is likely to result in the phase transformations of fcc-hcp in iridium and rhodium, and bcc-hcp in molybdenum, while evidently the transformations of bcc-fcc in molybdenum and chromium, hcp-bcc in technetium, rhenium and ruthenium are impossible. The pressure resulting in the transformations in the metals investigated equals approximately hundreds of kbar, or even approximately 1 Mbar for Ir

[The effect of work-related stress on the occurrence of increased blood pressure].

Science.gov (United States)

Budaj, A; Cybulski, J; Kułakowski, P; Makowska, E; Rezler, J; Lange, J; Gorzkowska, J; Abramowski, S

In 546 officials the arterial blood pressure was measured twice at the beginning and at the end of a working day, filling also an inquiry form. As hypertension systolic BP over 160 mm Hg (21.3 kPa) or more, and diastolic BP 96 mm Hg (12.7 kPa) or more were accepted. In 90 subjects (16.5%) above normal pressure values were found. Hypertension had been diagnosed previously in 50 subjects in this group (55.5%) but only 13 of them (26%) were treated systematically. Excessive stress of work was complained of by 62.6% of the subjects. Increased blood pressure was found significantly more frequently in the group perceiving excessive stress of work (19.9%) as compared to those not experiencing this stress (10.8%, p less than 0.1). In the group in managerial posts these proportions were 24.8% and 14.4% respectively (p less than 0.1). Blood pressure rise to abnormal levels during the working day occurred also significantly more frequently in the group experiencing it this was noted only in 1.6% of cases (p less than 0.5). The knowledge of own hypertension was very low in this group. These results indicate the necessity of increasing prophylactic measures in the form of greater frequency of control measurements of the blood pressure, better health education, and limitation of stress situations in working environment.

The inter-arm systolic blood pressure difference and risk of cardiovascular mortality: A meta-analysis of cohort studies.

Science.gov (United States)

Zhou, Ming; Gao, Zhen; Chen, Fei; Xu, Haijun; Dong, Xiao; Ma, Li

2016-01-01

The inter-arm systolic blood pressure difference (SBPD) is recommended to be in relation to potential cardiovascular disease (CVD). Previous studies yielded controversial results about the association between an inter-arm SBPD ≥ 10 mmHg or ≥15 mmHg and the risk of cardiovascular mortality. Therefore, we conducted this meta-analysis to investigate this association. We searched PubMed and Embase databases through December 31, 2014, and examined the references of retrieved articles to identify relevant cohort studies. We utilized Newcastle-Ottawa scale to assess the quality of included studies and calculated the summary risk estimates in a fixed/random-effect model. All data analyses were conducted using STATA version 11.0. A total of seven studies were identified. Compared with participants with an inter-arm SBPD arm SBPD ≥ 10 mmHg was 1.58 (95% CI: 1.3-1.93), and the pooled HR of cardiovascular mortality of participants with an inter-arm SBPD ≥ 15 mmHg versus those with an inter-arm SBPD arm SBPD may define a subpopulation at high risk of CVD events.

Value of radionuclide angiocardiography for determination of left ventricular volume in patients with valvular heart diseases (preliminary report)

International Nuclear Information System (INIS)

Madeja, G.; Konieczna, S.; Gosiewska-Marcinkowska, E.; Leszek, P.

1991-01-01

In 15 patients with mitral valve defect and 10 patients with aortic valve defect, left ventricular end-diastolic and end-systolic volumes were determined by gated radionuclide angiography. The results were compared with contrast ventriculography. The correlation coefficient between the two methods was much lower in cases of mitral valve diseases. (author). 1 tab

Could White Coat Ocular Hypertension Affect to the Accuracy of the Diagnosis of Glaucoma? Relationships Between Anxiety and Intraocular Pressure in a Simulated Clinical Setting.

Science.gov (United States)

Méndez-Ulrich, Jorge Luis; Sanz, Antoni; Feliu-Soler, Albert; Álvarez, María; Borràs, Xavier

2018-03-01

Sixty-one healthy subjects participated in a laboratory study carried out in a simulated clinical setting. Anticipatory anxiety-state was assessed at the arrival and immediately after, with no brief phase of adaptation, measurements of intraocular pressure, heart rate, systolic and diastolic blood pressure were collected. At the end of the procedure, anxiety-trait was also assessed. Results suggest that high levels of both anxiety-state and anxiety-trait significantly predicted a clinically relevant increase of intraocular pressure. Anxiety-state mediated the relationship between anxiety-trait and intraocular pressure, which also was found to be related with heart rate but not related to both systolic and diastolic blood pressure. These results suggest a common mechanism of regulation underlying anxiogenic variability found on both intraocular pressure and heart rate. A reduction in parasympathetic activity appears as a possible mechanism underlying to this phenomenon. This anxiety-enhanced intraocular pressure could be considered a phenomenon analogous to white coat hypertension found in the measurement of blood pressure; therefore, it probably should be taken into account in the clinical context to prevent errors in the diagnosis of glaucoma. Further research on cognitive and emotional regulation of intraocular pressure is needed to best characterize this hypothetical phenomenon.

Impairment of left ventricular function during coronary angioplastic occlusion evaluated with a nonimaging scintillation probe.

Science.gov (United States)

Hartmann, A; Maul, F D; Zimny, M; Klepzig, H; Vallbracht, C; Kneissl, H G; Schräder, R; Hör, G; Kaltenbach, M

1991-09-01

Impairment of left ventricular function during controlled myocardial ischemia induced by coronary angioplasty has been reported from angiographic and echocardiographic studies. Ejection fraction, peak ejection, peak filling rates, and end-systolic and end-diastolic volumes were investigated before, during and after coronary occlusion on-line with a nonimaging scintillation probe. The study consisted of 18 patients (mean age 59 +/- 10 years) with coronary artery stenosis of greater than 70%. During balloon inflation of 60 seconds' duration, coronary occlusion pressure was 31.6 +/- 12 mm Hg. There was no significant change in heart rate. Delay between first and second dilatation was 109 +/- 63 seconds. Ejection fraction decreased from 53 +/- 16 to 40 +/- 12% (first dilatation, p less than 0.01) and to 39 +/- 14% (second dilatation, p less than 0.01) and recovered to 51 +/- 16% 5 minutes after the second dilatation. Peak ejection rate was significantly reduced during the first and second balloon inflations. Peak filling rate decreased from 2.5 +/- 0.8 to 2.0 +/- 0.7 end-diastolic volume.s-1 (first dilatation, p less than 0.01) and to 1.8 +/- 0.7 end-diastolic volume.s-1 (second dilatation, p less than 0.01) and remained reduced at 2.2 +/- 0.7 end-diastolic volume.s-1 (p = not significant) at 5 minutes after the second dilatation. End-systolic and end-diastolic volumes increased significantly during the first and second dilatations and returned to normal after dilatation. It is concluded that short, controlled myocardial ischemia during coronary angioplasty leads to a decrease in systolic and diastolic left ventricular function. Sequential dilatations do not further decrease function if a sufficient interval is kept.

Automatic Extraction of Myocardial Mass and Volume Using Parametric Images from Dynamic Nongated PET.

Science.gov (United States)

Harms, Hendrik Johannes; Stubkjær Hansson, Nils Henrik; Tolbod, Lars Poulsen; Kim, Won Yong; Jakobsen, Steen; Bouchelouche, Kirsten; Wiggers, Henrik; Frøkiaer, Jørgen; Sörensen, Jens

2016-09-01

Dynamic cardiac PET is used to quantify molecular processes in vivo. However, measurements of left ventricular (LV) mass and volume require electrocardiogram-gated PET data. The aim of this study was to explore the feasibility of measuring LV geometry using nongated dynamic cardiac PET. Thirty-five patients with aortic-valve stenosis and 10 healthy controls underwent a 27-min (11)C-acetate PET/CT scan and cardiac MRI (CMR). The controls were scanned twice to assess repeatability. Parametric images of uptake rate K1 and the blood pool were generated from nongated dynamic data. Using software-based structure recognition, the LV wall was automatically segmented from K1 images to derive functional assessments of LV mass (mLV) and wall thickness. End-systolic and end-diastolic volumes were calculated using blood pool images and applied to obtain stroke volume and LV ejection fraction (LVEF). PET measurements were compared with CMR. High, linear correlations were found for LV mass (r = 0.95), end-systolic volume (r = 0.93), and end-diastolic volume (r = 0.90), and slightly lower correlations were found for stroke volume (r = 0.74), LVEF (r = 0.81), and thickness (r = 0.78). Bland-Altman analyses showed significant differences for mLV and thickness only and an overestimation for LVEF at lower values. Intra- and interobserver correlations were greater than 0.95 for all PET measurements. PET repeatability accuracy in the controls was comparable to CMR. LV mass and volume are accurately and automatically generated from dynamic (11)C-acetate PET without electrocardiogram gating. This method can be incorporated in a standard routine without any additional workload and can, in theory, be extended to other PET tracers. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Effect of large volume paracentesis on plasma volume--a cause of hypovolemia

International Nuclear Information System (INIS)

Kao, H.W.; Rakov, N.E.; Savage, E.; Reynolds, T.B.

1985-01-01

Large volume paracentesis, while effectively relieving symptoms in patients with tense ascites, has been generally avoided due to reports of complications attributed to an acute reduction in intravascular volume. Measurements of plasma volume in these subjects have been by indirect methods and have not uniformly confirmed hypovolemia. We have prospectively evaluated 18 patients (20 paracenteses) with tense ascites and peripheral edema due to chronic liver disease undergoing 5 liter paracentesis for relief of symptoms. Plasma volume pre- and postparacentesis was assessed by a 125 I-labeled human serum albumin dilution technique as well as by the change in hematocrit and postural blood pressure difference. No significant change in serum sodium, urea nitrogen, hematocrit or postural systolic blood pressure difference was noted at 24 or 48 hr after paracentesis. Serum creatinine at 24 hr after paracentesis was unchanged but a small but statistically significant increase in serum creatinine was noted at 48 hr postparacentesis. Plasma volume changed -2.7% (n = 6, not statistically significant) during the first 24 hr and -2.8% (n = 12, not statistically significant) during the 0- to 48-hr period. No complications from paracentesis were noted. These results suggest that 5 liter paracentesis for relief of symptoms is safe in patients with tense ascites and peripheral edema from chronic liver disease

Comparison of various state equations for approximation and extrapolation of experimental hydrogen molar volumes in wide temperature and pressure intervals

International Nuclear Information System (INIS)

Didyk, A.Yu.; Altynov, V.A.; Wisniewski, R.

2009-01-01

The numerical analysis of practically all existing formulae such as expansion series, Tait, logarithm, Van der Waals and virial equations for interpolation of experimental molar volumes versus high pressure was carried out. One can conclude that extrapolating dependences of molar volumes versus pressure and temperature can be valid. It was shown that virial equations can be used for fitting experimental data at relatively low pressures P<3 kbar too in distinction to other equations. Direct solving of a linear equation of the third order relatively to volume using extrapolated virial coefficients allows us to obtain good agreement between existing experimental data for high pressure and calculated values

Mechanisms of lower body negative pressure-induced syncope

Science.gov (United States)

Davrath, Linda Ruble

Although extensively investigated, the mechanisms of post-spaceflight orthostatic intolerance have not been elucidated. The working hypothesis was that a markedly reduced left ventricular end-systolic volume (LVESV) would be achieved during progressive, presyncopal-limited LBNP and would cause bradycardia and a fall in blood pressure, thus triggering syncope. Eight healthy men, age 25.1 ± 1.3 years, volunteered for the study. Subjects were exposed to graded levels of LBNP on two separate occasions. Changes in left ventricular end-diastolic volume and LVESV were measured, using two-dimensional echocardiography, at each stage of LBNP from rest to presyncope. Plasma venous blood samples were withdrawn at the end of each stage of the LBNP protocol for the measurement of plasma venous catecholamines and plasma renin activity (PRA). Catecholamines were analyzed by HPLC with electro-chemical detection, and PRA was determined by radioimmunoassay. All subjects reached presyncope during the LBNP. LVESV decreased by 28% at presyncope with no evidence of ventricular cavity obliteration. Norepinephrine (NE) increased by 44% from rest to presyncope, but no epinephrine surge was detected (35% increase from rest to presyncope). These data indicate that it is possible to initiate syncope with only a 28% decrease in LVESV, and that sympatho-inhibition and bradycardia are not required elements for syncope to occur. To investigate the effect of moderate sodium restriction on cardiovascular hemodynamics and orthostatic tolerance, presyncopal LBNP testing was performed. Urinary sodium excretion was significantly higher on the normal-sodium diet when compared with the sodium-restricted diet, but urinary potassium was not different. Cumulative stress index (655 ± 460 on normal-sodium diet vs. 639 ± 388 on sodium-restricted diet) scores were not different. Cardiac volumes, blood pressure and total peripheral resistance were not different at any stage of the LBNP between the diets, nor

Retinopathy of Prematurity Is Associated with Increased Systolic Blood Pressure in Adults Who Were Born Preterm.

Science.gov (United States)

Kistner, Anna; Jacobson, Lena; Östergren, Jan; Hellström, Ann

2017-01-01

Adults born preterm are at risk of developing cardiovascular morbidities. The aim of this study was to evaluate the relationship between retinopathy of prematurity (ROP) and blood pressure (BP) and salivary cortisol levels during adulthood. Sixty-nine subjects (mean age 22.6 years) were included. Subjects were adults who were: (a) ex-preterm infants with severe ROP (n = 22), born at gestational age (GA) <30 weeks with a birth weight (BW) <1,000 g, (b) ex-preterm infants with no/mild ROP (n = 21), born at GA <28 weeks with a BW <1,000 g, or (c) full-term controls (n = 26). Anthropometric data, office BP, ambulatory BP, and morning and evening salivary cortisol were analyzed. As adults, ex-preterm infants with severe ROP had on average 7.4 mm Hg higher systolic office BP than those with no/mild ROP (p = 0.019) and controls (p = 0.007). A high cortisol level, tall height, and severe ROP were independent predictors of higher ambulatory systolic BP during adulthood in forward stepwise regression analysis, independent of GA. Our results indicate that preterm infants with severe abnormal retinal vascular development during the neonatal period may be at an increased risk for increased BP during adulthood. We found no differences between those with no/mild ROP as infants and controls with regard to BP data. © 2017 The Author(s) Published by S. Karger AG, Basel.

Fuzzy Control of Tidal volume, Respiration number and Pressure value

OpenAIRE

Hasan Guler; Fikret Ata

2010-01-01

In this study, control of tidal volume, respiration number and pressure value which are arrived to patient at mechanical ventilator device which is used in intensive care units were performed with fuzzy logic controller. The aim of this system is to reduce workload of aneshesiologist. By calculating tidal volume, respiration number and pressure value, the error Pe(k) between reference pressure value (Pref) and pressure of gas given ill person (Phasta) and error change rate ;#948;Pe(k) were co...

Reliability of blood pressure parameters for dry weight estimation in hemodialysis patients.

Science.gov (United States)

Susantitaphong, Paweena; Laowaloet, Suthanit; Tiranathanagul, Khajohn; Chulakadabba, Adhisabandh; Katavetin, Pisut; Praditpornsilpa, Kearkiat; Tungsanga, Kriang; Eiam-Ong, Somchai

2013-02-01

Chronic volume overload resulting from interdialytic weight gain and inadequate fluid removal plays a significant role in poorly controlled high blood pressure. Although bioimpedance has been introduced as an accurate method for assessing hydration status, the instrument is not available in general hemodialysis (HEMO) centers. This study was conducted to explore the correlation between hydration status measured by bioimpedance and blood pressure parameters in chronic HEMO patients. Multifrequency bioimpedance analysis was used to determine pre- and post-dialysis hydration status in 32 stable HEMO patients. Extracellular water/total body water (ECW/TBW) determined by sum of segments from bioimpedance analysis was used as an index of hydration status. The mean age was 57.9 ± 16.4 years. The mean dry weight and body mass index were 57.7 ± 14.5 kg and 22.3 ± 4.7 kg/m(2), respectively. Pre-dialysis ECW/TBW was significantly correlated with only pulse pressure (r = 0.5, P = 0.003) whereas post-dialysis ECW/TBW had significant correlations with pulse pressure, systolic blood pressure, and diastolic blood pressure (r = 0.6, P = 0.001, r = 0.4, P = 0.04, r = -0.4, and P = 0.02, respectively). After dialysis, the mean values of ECW/TBW, systolic blood pressure, mean arterial pressure, and pulse pressure were significantly decreased. ECW/TBW was used to classify the patients into normohydration (≤ 0.4) and overhydration (>0.4) groups. Systolic blood pressure, mean arterial pressure, and pulse pressure significantly reduced after dialysis in the normohydration group but did not significantly change in the overhydration group. Pre-dialysis pulse pressure, post-dialysis pulse pressure, and post-dialysis systolic blood pressure in the overhydration group were significantly higher than normohydration group. Due to the simplicity and cost, blood pressure parameters, especially pulse pressure, might be a simple reference for clinicians to determine hydration status in HEMO

Measuring systolic ankle and toe pressure using the strain gauge technique--a comparison study between mercury and indium-gallium strain gauges

DEFF Research Database (Denmark)

Broholm, Rikke; Wiinberg, Niels; Simonsen, Lene

2014-01-01

BACKGROUND: Measurement of the ankle and toe pressures are often performed using a plethysmograph, compression cuffs and a strain gauge. Usually, the strain gauge contains mercury but other alternatives exist. From 2014, the mercury-containing strain gauge will no longer be available in the Europ......BACKGROUND: Measurement of the ankle and toe pressures are often performed using a plethysmograph, compression cuffs and a strain gauge. Usually, the strain gauge contains mercury but other alternatives exist. From 2014, the mercury-containing strain gauge will no longer be available...... in the European Union. The aim of this study was to compare an indium-gallium strain gauge to the established mercury-containing strain gauge. METHODS: Consecutive patients referred to the Department of Clinical Physiology and Nuclear Medicine at Bispebjerg and Frederiksberg Hospitals for measurements of systolic...... ankle and toe pressures volunteered for the study. Ankle and toe pressures were measured twice with the mercury and the indium-gallium strain gauge in random order. Comparison of the correlation between the mean pressure using the mercury and the indium-gallium device and the difference between the two...

Synergistic effects of remote perconditioning with terminal blood cardioplegia in an in vivo piglet model.

Science.gov (United States)

Abe, Takayuki; Morita, Kiyozo; Shinohara, Gen; Hashimoto, Kazuhiro; Nishikawa, Masako

2017-09-01

This study tested the hypothesis that remote perconditioning offers effective and synergistic cardioprotection to terminal warm blood cardioplegia for prompt ventricular recovery after prolonged cardioplegic arrest in an in vivo piglet model. Twenty-four piglets were subjected to 120 min of single-dose cardioplegic arrest and were divided into 4 groups according to the mode of reperfusion: control (simple aortic unclamp), remote perconditioning, terminal warm blood cardioplegia or remote perconditioning + terminal warm blood cardioplegia; remote perconditioning (4 cycles of 5-min ischaemia-reperfusion of the lower limb) was applied prior to aortic unclamping. Left ventricular systolic and diastolic functions were assessed by pressure-volume loop analysis at baseline and after 60 min of reperfusion. Biochemical injury was evaluated by plasma troponin T level. The control group showed decreased end-systolic elastance, preload recruitable stroke work and inverse of end-diastolic pressure-volume relationship of 51.3 ± 14.0%, 46.1 ± 22.5% and 34.8 ± 14.9%, respectively. Percentage recovery of end-systolic elastance and preload recruitable stroke work were significantly better with terminal warm blood cardioplegia (with or without remote perconditioning) (end-systolic elastance: 95% confidence interval, 38.6-84.1; preload recruitable stroke work: 95% confidence interval, 0.4-54.3). Percentage recovery of inverse of end-diastolic pressure-volume relationship was significantly better in the remote perconditioning groups (with or without terminal warm blood cardioplegia) (95% confidence interval, 1.6-41.6). No synergistic effects of remote perconditioning and terminal warm blood cardioplegia on troponin T release were noted. Remote perconditioning offers promising synergistic cardioprotection to terminal warm blood cardioplegia, implicating potential clinical benefit by contributing to prompt left ventricular functional recovery during paediatric open

Assessment of various systolic phase indexes for the detection of coronary artery disease by multi-gated blood pool imaging at rest

International Nuclear Information System (INIS)

Narita, Michihiro; Kurihara, Tadashi; Murano, Kenichi; Usami, Masahisa; Honda, Minoru; Kanao, Keisuke

1982-01-01

After Tc-99m was labeled with red blood cells in vivo, multi-gated blood pool imaging (MGBPI) was obtained at anterior and 40-degree left anterior oblique (LAO) position at rest. In addition to left ventricular (LV) ejection fraction (EF) and wall motion (WM) abnormality, first-third EF, mean normalized systolic ejection rate, SdV/dt/EDV (LV peak ejection rate normalized by end-diastolic volume) and SdV/dt/V (peak ejection rate normalized by LV volume at the peak ejection) were calculated. Patients were divided into 3 groups; Normal (n = 14), coronary artery disease (CAD) with normal EF (> = 55%) and normal WM (Group I, n = 16), and CAD with abnormal EF and/or WM abnormality (Group II, n = 31). In all subjects of Normal and 13 patients of Group I, graded supine exercise stress MGBPI was performed at LAO position by using bicycle ergometer. All systolic phase indexes were correlated well with EF (r > = 0.77, p - 1 , p - 1 as a criteria of CAD, sensitivity of this index was 91% (100% in Group II and 75% in Group I). This sensitivity in Group I was identical with that of exercise stress MGBPI. Specificity of SdV/dt/V (86%) was a little inferior to that of exercise stress MGBPI (93%), but it was not statistically significant. In conclusion, SdV/dt/V is a useful systolic phase index to detect CAD. (J.P.N.)

Utilization of the lower inflection point of the pressure-volume curve results in protective conventional ventilation comparable to high frequency oscillatory ventilation in an animal model of acute respiratory distress syndrome

Directory of Open Access Journals (Sweden)

Felipe S. Rossi

2008-01-01

Full Text Available INTRODUCTION: Studies comparing high frequency oscillatory and conventional ventilation in acute respiratory distress syndrome have used low values of positive end-expiratory pressure and identified a need for better recruitment and pulmonary stability with high frequency. OBJECTIVE: To compare conventional and high frequency ventilation using the lower inflection point of the pressure-volume curve as the determinant of positive end-expiratory pressure to obtain similar levels of recruitment and alveolar stability. METHODS: After lung lavage of adult rabbits and lower inflection point determination, two groups were randomized: conventional (positive end-expiratory pressure = lower inflection point; tidal volume=6 ml/kg and high frequency ventilation (mean airway pressures= lower inflection point +4 cmH2O. Blood gas and hemodynamic data were recorded over 4 h. After sacrifice, protein analysis from lung lavage and histologic evaluation were performed. RESULTS: The oxygenation parameters, protein and histological data were similar, except for the fact that significantly more normal alveoli were observed upon protective ventilation. High frequency ventilation led to lower PaCO2 levels. DISCUSSION: Determination of the lower inflection point of the pressure-volume curve is important for setting the minimum end expiratory pressure needed to keep the airways opened. This is useful when comparing different strategies to treat severe respiratory insufficiency, optimizing conventional ventilation, improving oxygenation and reducing lung injury. CONCLUSIONS: Utilization of the lower inflection point of the pressure-volume curve in the ventilation strategies considered in this study resulted in comparable efficacy with regards to oxygenation and hemodynamics, a high PaCO2 level and a lower pH. In addition, a greater number of normal alveoli were found after protective conventional ventilation in an animal model of acute respiratory distress syndrome.

Left ventricular mechanical adaptation to chronic aortic regurgitation in intact dogs

International Nuclear Information System (INIS)

Florenzano, F.; Glantz, S.A.

1987-01-01

Increased and end-diastolic wall stress has been hypothesized to stimulate left ventricular (LV) hypertrophy following volume overload. The authors instrumented intact-chest dogs with radiopaque markers in both ventricles and created volume overload by puncturing one aortic valve cusp. An x-ray system with biplane fluoroscopic and cineradiographic capabilities was used. End-diastolic stress increased immediately, then fell over 3 mo as the heart hypertrophied. End-systolic stress did not change significantly. Chamber contractility, quantified as E/sub max/, the end-systolic pressure-volume line slope, increased. E/sub max/ normalized by multiplying by LV mass increased following the lesion before but not after β-blockade with propranolol and did not change significantly over time, suggesting that chamber contractility changed because of increased mass and sympathetic tone rather than changed intrinsic muscle function. LV mass did not initially correlate with lesion size, but steady-state mass did. Over the range of lesions the authors produced, increased end-diastolic wall stress appears to stimulate hypertrophy at a fixed rate, which stops when end-diastolic wall stress has been reduced to an acceptable level

Diastolic effects of chronic digitalization in systolic heart failure.

Science.gov (United States)

Hassapoyannes, C A; Bergh, M E; Movahed, M R; Easterling, B M; Omoigui, N A

1998-10-01

The efficacy of short-term digitalization on exercise tolerance may, in part, reflect enhanced diastolic performance. However, cardiac glycosides can impair ventricular relaxation from cytosolic Ca++ overload. To detect any time-dependent adverse effect, we assessed the diastolic function after long-term use of digitalis in patients with mild to moderate systolic left ventricular failure. From a cohort of 80 patients who received long-term, randomized, double-blind treatment with digitalis versus placebo at the WJB Dorn Veterans Affairs Medical Center, 38 survivors were evaluated at the end of follow-up (mean 48.4 months) with evaluators blinded to treatment used. Each survivor underwent equilibrium scintigraphic and echocardiographic assessment of diastolic function. Peak and mean filling rates normalized with filling volume (FV), diastolic phase durations normalized with duration of diastole, and filling fractions were measured from the time-activity curve. The isovolumic relaxation period and ventricular dimensions were computed echocardiographically. By actual-treatment-received analysis, treated versus untreated patients manifested a trend toward longer isovolumic relaxation (80.76 ms vs 61.54 ms, P = .06) but a markedly lower peak rapid filling rate (6.39 FV/sec vs 10.56 FV/sec, P = .02) despite comparable loading conditions. In addition, treated patients exhibited a lower mean rate of rapid filling (2.75 FV/sec vs 3.78 FV/sec, P = .05) in the absence of a longer rapid filling duration. However, the end-diastolic ventricular dimension did not differ between the 2 groups. Similar results were obtained by intention-to-treat analysis. Importantly, the mortality rate from worsening heart failure in the inception cohort was lower in the digitalis group versus the placebo group (P = .05) with no difference in total cardiac or all-cause mortality. After long-term digitalization for systolic left ventricular failure, cross-sectional comparison with a control group

The effect of comorbidity on glycemic control and systolic blood pressure in type 2 diabetes: a cohort study with 5 year follow-up in primary care.

NARCIS (Netherlands)

Luijks, H.; Biermans, M.; Bor, H.; Weel, C. van; Lagro-Janssen, T.; Grauw, W. de; Schermer, T.

2017-01-01

Aims: To explore the longitudinal effect of chronic comorbid diseases on glycemic control (HbA1C) and systolic blood pressure (SBP) in type 2 diabetes patients. Methods: In a representative primary care cohort of patients with newly diagnosed type 2 diabetes in The Netherlands (n = 610), we tested

Body Size Predicts Cardiac and Vascular Resistance Effects on Men's and Women's Blood Pressure

Directory of Open Access Journals (Sweden)

Joyce M. Evans

2017-08-01

Full Text Available Key Points SummaryWe report how blood pressure, cardiac output and vascular resistance are related to height, weight, body surface area (BSA, and body mass index (BMI in healthy young adults at supine rest and standing.Much inter-subject variability in young adult's blood pressure, currently attributed to health status, may actually result from inter-individual body size differences.Each cardiovascular variable is linearly related to height, weight and/or BSA (more than to BMI.When supine, cardiac output is positively related, while vascular resistance is negatively related, to body size. Upon standing, the change in vascular resistance is positively related to size.The height/weight relationships of cardiac output and vascular resistance to body size are responsible for blood pressure relationships to body size.These basic components of blood pressure could help distinguish normal from abnormal blood pressures in young adults by providing a more effective scaling mechanism.Introduction: Effects of body size on inter-subject blood pressure (BP variability are not well established in adults. We hypothesized that relationships linking stroke volume (SV, cardiac output (CO, and total peripheral resistance (TPR with body size would account for a significant fraction of inter-subject BP variability.Methods: Thirty-four young, healthy adults (19 men, 15 women participated in 38 stand tests during which brachial artery BP, heart rate, SV, CO, TPR, and indexes of body size were measured/calculated.Results: Steady state diastolic arterial BP was not significantly correlated with any index of body size when subjects were supine. However, upon standing, the more the subject weighed, or the taller s/he was, the greater the increase in diastolic pressure. Systolic pressure strongly correlated with body weight and height both supine and standing. Diastolic and systolic BP were more strongly related to height, weight and body surface area than to body mass

Admission Systolic Blood Pressure Predicts the Number of Blood Pressure Medications at Discharge in Patients With Primary Intracerebral Hemorrhage.

Science.gov (United States)

Khawaja, Ayaz M; Shiue, Harn; Boehme, Amelia K; Albright, Karen C; Venkatraman, Anand; Kumar, Gyanendra; Lyerly, Michael J; Hays-Shapshak, Angela; Mirza, Maira; Gropen, Toby I; Harrigan, Mark R

2018-03-01

Control of systolic blood pressure (SBP) after primary intracerebral hemorrhage improves outcomes. Factors determining the number of blood pressure medications (BPM) required for goal SBP<160 mm Hg at discharge are unknown. We hypothesized that higher admission-SBPs require a greater number of BPM for goal discharge-SBP<160 mm Hg, and investigated factors influencing this goal. We conducted a retrospective review of 288 patients who presented with primary intracerebral hemorrhage. Admission-SBP was obtained. Primary outcome was the number of BPM at discharge. Comparison was made between patients presenting with and without a history of hypertension, and patients discharged on <3 and ≥3 BPM. Patients with hypertension history had a higher median admission-SBP compared with those without (180 vs. 157 mm Hg, P=0.0001). In total, 133 of 288 (46.2%) patients were discharged on <3 BPM; 155/288 (53.8%) were discharged on ≥3 BPM. Hypertension history (P<0.0001) and admission-SBP (P<0.0001) predicted the number of BPM at discharge. In patients without hypertension history, every 10 mm Hg increase in SBP resulted in an absolute increase of 0.5 BPM at discharge (P=0.0011), whereas in those with hypertension, the absolute increase was 1.3 BPM (P=0.0012). In comparison with patients discharged on <3 BPM, patients discharged on ≥3 BPM were more likely to have a higher median admission-SBP, be younger in age, belong to the African-American race, have a history of diabetes, have higher median admission-National Institutes of Health Stroke Scale and modified Rankin Scale of 4 to 5 at discharge. An understanding of the factors influencing BPM at discharge may help clinicians better optimize blood pressure control both before and after discharge.

The deflation limb of the pressure-volume relationship in infants during high-frequency ventilation.

Science.gov (United States)

Tingay, David G; Mills, John F; Morley, Colin J; Pellicano, Anastasia; Dargaville, Peter A

2006-02-15

The importance of applying high-frequency oscillatory ventilation with a high lung volume strategy in infants is well established. Currently, a lack of reliable methods for assessing lung volume limits clinicians' ability to achieve the optimum volume range. To map the pressure-volume relationship of the lung during high-frequency oscillatory ventilation in infants, to determine at what point ventilation is being applied clinically, and to describe the relationship between airway pressure, lung volume, and oxygenation. In 12 infants, a partial inflation limb and the deflation limb of the pressure-volume relationship were mapped using a quasi-static lung volume optimization maneuver. This involved stepwise airway pressure increments to total lung capacity, followed by decrements until the closing pressure of the lung was identified. Lung volume and oxygen saturation were recorded at each airway pressure. Lung volume was measured using respiratory inductive plethysmography. A distinct deflation limb could be mapped in each infant. Overall, oxygenation and lung volume were improved by applying ventilation on the deflation limb. Maximal lung volume and oxygenation occurred on the deflation limb at a mean airway pressure of 3 and 5 cm H(2)O below the airway pressure approximating total lung capacity, respectively. Using current ventilation strategies, all infants were being ventilated near the inflation limb. It is possible to delineate the deflation limb in infants receiving high-frequency oscillatory ventilation; in doing so, greater lung volume and oxygenation can be achieved, often at lower airway pressures.

Improved determination of left ventricular volume with myocardial tagging

International Nuclear Information System (INIS)

Peshock, R.M.; Takai, H.; Baker, K.V.; Clarke, G.D.; McDonald, G.G.; Parkey, R.W.

1991-01-01

Cine MR imaging can be used to determine ventricular volume and ejection fraction. However, definition of the endocardial surface can be difficult, leading some investigators to suggest that black-blood studies are preferable. Grid tagging with use of spatial modulation of magnetization has been used to improve assessments of wall motion. The purpose of this paper, is to determine if grid tagging would also facilitate definition of the endocardial border for volume and ejection fraction calculations. Grid tagging based on spatial modulation of magnetization was implemented on a Toshiba 0.5-T MR imaging device. Standard RAO images were obtained in 10 normal volunteers with use of standard cine MR imaging sequences (33/22) with and without grid tagging. Images were analyzed to determine ventricular volume, cardiac output and wall motion. Images obtained without tagging generally showed good contrast at end diastole, but definition of the endocardial border was frequently more difficult in middle to late systole. Images with tagging provided significantly better definition of endocardial borders, particularly during systole

Effects of short-term pressure-controlled ventilation on gas exchange, airway pressures, and gas distribution in patients with acute lung injury/ARDS: comparison with volume-controlled ventilation.

Science.gov (United States)

Prella, Maura; Feihl, François; Domenighetti, Guido

2002-10-01

The potential clinical benefits of pressure-controlled ventilation (PCV) over volume-controlled ventilation (VCV) in patients with acute lung injury (ALI) or ARDS still remain debated. We compared PCV with VCV in patients with ALI/ARDS with respect to the following physiologic end points: (1) gas exchange and airway pressures, and (2) CT scan intrapulmonary gas distribution at end-expiration. Prospective, observational study. A multidisciplinary ICU in a nonuniversity, acute-care hospital. Ten patients with ALI or ARDS (9 men and 1 woman; age range, 17 to 80 years). Sequential ventilation in PCV and VCV with a constant inspiratory/expiratory ratio, tidal volume, respiratory rate, and total positive end-expiratory pressure; measurement of gas exchange and airway pressures; and achievement of CT sections at lung base, hilum, and apex for the quantitative analysis of lung densities and of aerated vs nonaerated zones. PaO(2), PaCO(2), and PaO(2)/fraction of inspired oxygen ratio levels did not differ between PCV and VCV. Peak airway pressure (Ppeak) was significantly lower in PCV compared with VCV (26 +/- 2 cm H(2)O vs 31 +/- 2 cm H(2)O; p mean +/- SEM). The surface areas of the nonaerated zones as well as the total areas at each section level were unchanged in PCV compared with VCV, except at the apex level, where there was a significantly greater nonaerated area in VCV (11 +/- 2 cm(2) vs 9 +/- 2 cm(2); p mean CT number of each lung (20 lungs from 10 patients) was similar in the two modes, as were the density values at the basal and apical levels; the hilum mean CT number was - 442 +/- 28 Hounsfield units (HU) in VCV and - 430 +/- 26 HU in PCV (p lower Ppeaks through the precise titration of the lung distending pressure, and might be applied to avoid regional overdistension by means of a more homogeneous gas distribution.

The volume of the carotid bodies and blood pressure variability and pulse pressure in patients with essential hypertension

International Nuclear Information System (INIS)

Jaźwiec, P.; Gać, P.; Poręba, M.; Sobieszczańska, M.; Mazur, G.; Poręba, R.

2016-01-01

Aim: To assess the relationship between the volume of the carotid bodies (V rCB+lCB ) examined by means of computed tomography angiography (CTA) and blood pressure variability and pulse pressure (PP) in 24-hour ambulatory blood pressure monitoring (ABPM) in patients with essential hypertension. Materials and methods: A group of 52 patients with essential hypertension was examined (mean age: 68.32±12.31 years), the sizes of carotid bodies were measured by means of carotid artery CTA, and 24-hour ABPM was carried out. The 24-hour ABPM established systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), PP, SBP variability (SBPV), and DBP variability (DBPV). Results: SBP, MAP, and SBPV were significantly higher in the group of hypertension patients with V rCB+lCB equal to or above the median than in the group of hypertension patients with V rCB+lCB less than the median, as well as in the group of hypertension patients with oversized carotid bodies, than in the group of hypertension patients with normal V rCB+lCB . Moreover, the PP was statistically significantly higher in the group of hypertension patients with V rCB+lCB equal to or above the median than in the group of hypertension patients with V rCB+lCB less than the median. The existence of statistically significant positive linear relationships was revealed between V rCB+lCB and SBP, PP, and SBPV. A higher body mass index, older age, smoking, and higher V rCB+lCB are independent risk factors increasing SBPV in the research group. Conclusion: A positive relationship between the size of the carotid bodies and variability of the SBP and PP is observed in patients with essential hypertension. - Highlights: • Purpose. Determination of the relationships: V rCB+lCB vs. BPV and V rCB+lCB vs. PP. • Positive linear correlations were documented between V rCB+lCB and SBP, PP and SBPV. • Higher BMI, age, V rCB+lCB and smoking are independent risk factor of increased SBPV.

Ambulatory blood pressure monitoring in children and adolescents with type-1 diabetes mellitus and its relation to diabetic control and microalbuminuria

Directory of Open Access Journals (Sweden)

Mitra Basiratnia

2012-01-01

Full Text Available Diabetes mellitus (DM is now considered as the major cause of end-stage kidney failure, and hypertension (HTN is one of the main determinants of progression of renal disease. The aim of this study was to assess the role of blood pressure (BP by ambulatory blood pressure monitoring (ABPM in children and adolescents with type-1 DM and its correlation with micro-albuminuria (MA and diabetic control. Eighty-one patients with type-1 DM (mean age 13 ± 4 years, whose duration of DM was at least two years, were enrolled in this study. The prevalence of HTN based on ABPM was 28.4%, while by casual method it was 32.1%. The pattern of HTN was as follows: mean systolic HTN 27.2%, mean diastolic HTN 11.2%, daytime systolic HTN 17.3%, daytime diastolic HTN 6.2%, night systolic HTN 30.9%, and night diastolic HTN 29.7%. The systolic and diastolic BP loads were 33.4 and 27.2%, respectively. About 70.4% of the patients were non-dippers, 12.4% had masked HTN, and 3.7% had white coat HTN. The pre-valence of MA was 34.6% and that of abnormal HbA 1 c was 82.7%. There was no correlation bet-ween HTN and both MA and HbA 1 c; also, no correlation was found between the duration of dia-betes and HbA 1 c. Moreover, no significant correlation was found between the duration of diabetes and MA (P = 0.080. Despite the high prevalence of abnormal BP profile among diabetic children, prospective longitudinal studies considering the other major risk factors, particularly genetic factors, which have an impact on the progression to diabetic nephropathy, are recommended.

Effects of renal sympathetic denervation on 24-hour blood pressure variability

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Christine Stefanie Zuern

2012-05-01

Full Text Available Background: In patients with arterial hypertension, increased blood pressure (BP variability contributes to end organ damage independently from mean levels of arterial BP. Increased BP variability has been linked to alterations in autonomic function including sympathetic overdrive. We hypothesized that catheter-based renal sympathetic denervation (RDN confers beneficial effects on BPV. Methods and Results: Eleven consecutive patients with therapy-refractory arterial hypertension (age 68.9±7.0 years; baseline systolic BP 189±23mmHg despite medication with 5.6±2.1 antihypertensive drugs underwent bilateral RDN. Twenty-four hour ambulatory blood pressure monitoring (ABPM was performed before RDN and six months thereafter. BPV was primarily assessed by means of standard deviation of 24-hour systolic arterial blood pressures (SDsys. Secondary measures of BPV were maximum systolic blood pressure (MAXsys and maximum difference between two consecutive readings of systolic BP (deltamaxsys over 24 hours. Six months after RDN, SDsys, MAXsys and deltamaxsys were significantly reduced from 16.9±4.6mmHg to 13.5±2.5mmHg (p=0.003, from 190±22mmHg to 172±20mmHg (p<0.001 and from 40±15mmHg to 28±7mmHg (p=0.006, respectively, without changes in concomitant antihypertensive therapy. Reductions of SDsys, MAXsys and deltamaxsys were observed in 10/11 (90.9%, 11/11 (100% and 9/11 (81.8% patients, respectively. Although we noted a significant reduction of systolic office blood pressure by 30.4±27.7mmHg (p=0.007, there was only a trend in reduction of average systolic BP assessed from ABPM (149±19mmHg to 142±18mmHg; p=0.086.Conclusions: In patients with therapy-refractory arterial hypertension, RDN leads to significant reductions of BP variability. Effects of RDN on BPV over 24 hours were more pronounced than on average levels of BP.

Value of radionuclide angiocardiography for determination of left ventricular volume in patients with valvular heart disease

International Nuclear Information System (INIS)

Konieczna, S.; Madeja, G.; Gosiewska-Marcinkowska, E.; Szumilak, B.; Brodzki, L.M.; Leszek, P.

1992-01-01

The aim of this study was to investigate usability of the Massardo method in calculating the left ventricular volume in patients with valvular defect. The group consisted of 21 patients with mitral defect. Left ventricular volumes obtained by contrast ventriculography were used for reference. The correlation coefficient between these two methods was 0.94, SEE=29 ml, V nucl =0.94 V c.vent +11. The end-systolic and end-diastolic outlines were marked manually. We concluded that the Massardo methods is an effective method of calculating the left ventricular volume also in group of patients with mitral defect. (author). 11 refs, 4 tabs

Effects of garlic on blood pressure in patients with and without systolic hypertension: a meta-analysis.

Science.gov (United States)

Reinhart, Kurt M; Coleman, Craig I; Teevan, Colleen; Vachhani, Payal; White, C Michael

2008-12-01

Garlic has been suggested to lower blood pressure; however, studies evaluating this parameter have provided conflicting results. To examine the effect of garlic on blood pressure in patients with and without elevated systolic blood pressure (SPB) through meta-analyses of randomized controlled trials. A systematic search of MEDLINE, CINAHL, and the Cochrane Central Register of Controlled Trials was conducted to identify randomized controlled trials in humans evaluating garlic's effect on blood pressure. All databases were searched from their inception through June 26, 2008, using the key words garlic, Allium sativum, and allicin. A manual search of published literature was used to identify additional relevant studies. To be included in the analysis, studies must have been written in English or German and reported endpoints of SBP or diastolic blood pressure (DBP). Studies whose population had a mean baseline SBP greater than 140 mm Hg were evaluated separately from those whose population had lower baseline blood pressures. Garlic's effect on SBP and DBP was treated as a continuous variable and weighted mean differences were calculated using a random-effects model. Ten trials were included in the analysis; 3 of these had patients with elevated SBP. Garlic reduced SBP by 16.3 mm Hg (95% CI 6.2 to 26.5) and DBP by 9.3 mm Hg (95% CI 5.3 to 13.3) compared with placebo in patients with elevated SBP. However, the use of garlic did not reduce SBP or DBP in patients without elevated SBP. There was only a minor degree of heterogeneity in the analyses and publication bias did not appear to influence the results. This meta-analysis suggests that garlic is associated with blood pressure reductions in patients with an elevated SBP although not in those without elevated SBP. Future research should focus on the impact of garlic on clinical events and the assessment of the long-term risk of harm.

Investigation of effect of blood pressure and heart rate changes in different positions (lying and sitting on hypotension incidence rate after spinal anesthesia in patients undergoing caesarean section

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Nahid Manouchehrian

2016-07-01

Full Text Available Due to the relatively high prevalence of hypotension (20% -40% after spinal anesthesia as well as the adverse effects of hypotension on mother and baby, it is better to prevent hypotension as much as possible. Therefore, this study is aimed to determine the relationship between postural blood pressure and heart rate changes and hypotension incidence rate after spinal anesthesia in cesarean section.63 women aging18 to 45years old with fullterm pregnancy, who were candidate for caesarean section with spinal anesthesia, entered the study. Afterwards, the diastolic, systolic, and mean arterial pressures as well as the heart rate (pulse in different positions (sitting, lying, and left lateral were measured. After spinal anesthesia, the patients' blood pressure was measured and recorded every minute until the10thmin, then every 3 minute until the15thmin, and then every 5 minute until the end of cesarean section. Data analysis was performed using SPSS (ver. 19 software, descriptive statistics, one-way ANOVA, and post hoc Bonferroni test. In this study, the hypotension incidence rate was 30% and the orthostatic variation rate of the systolic blood pressure in more than half of the people was between 4.39 to 13.49psi, which showed the highest variation compared to the diastolic pressure, mean arterial blood pressure (or: mean arterial pressure [MAP], and heart(pulse. Considering the correlation coefficient of 0.27, the systolic blood pressure in the lateral position has the highest relationship with the incidence of hypotension. The postural systolic blood pressure changes in patients prior to the spinal anesthesia can be a predictive factor for the post-spinal hypotension incidence.

Morphological and Functional Measurements of the Heart Obtained by Magnetic Resonance Imaging in Brazilians

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Macedo, Robson, E-mail: robmacedo@yahoo.com [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil); Fernandes, Juliano Lara [Universidade Estadual de Campinas, Campinas, SP (Brazil); Andrade, Solange Souza; Rochitte, Carlos Eduardo [Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Lima, Kênio Costa; Maciel, Álvaro Campos Cavalcanti [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil); Maciel, Fernanda Cunha; Alves, Geraldo Souza Pinho [Universidade Potiguar, Natal, RN (Brazil); Coelho, Otávio Rizzi [Universidade Estadual de Campinas, Campinas, SP (Brazil); Diniz, Rosiane Viana Zuza [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil)

2013-07-15

Still today, measurements used as a reference in the cardiac magnetic resonance imaging have been obtained mainly from studies carried out in North-American and European populations. To obtain measurements of the diastolic diameter, systolic diameter, end diastolic volume, end systolic volume, ejection fraction, and myocardial mass of the left and right ventricles in Brazilians. 54 men and 53 women, with mean age of 43.4 ± 13.1 years, asymptomatic, with no cardiomyopathies, have been subjected to the cardiac magnetic resonance imaging, using a balanced steady state free precession technique. The averages and the standard deviations of the parameters for the left ventricle have been: diastolic diameter =4.8 ± 0.5 cm; systolic diameter = 3.0 ± 0.6 cm; end diastolic volume = 128.4 ± 29.6 mL; end systolic volume = 45.2 ± 16.6 mL; ejection fraction = 65.5 ± 6.3%; mass = 95.2 ± 30.8 g. For the right ventricle, they have been: diastolic diameter = 3.9 ± 1.3 cm; systolic diameter = 2.5 ± 0.5 cm; end diastolic volume = 126.5 ± 30.7 mL; end systolic volume = 53.6 ± 18.4 mL; ejection fraction = 58.3 ± 8.0%, and mass = 26.1 ± 6.1 g. The masses and the volumes were significantly greater in the men, except for the end systolic volume of the left ventricle. The ejection fraction of the right ventricle has been significantly greater in the women. There has been a significant and inverted correlation of the systolic volume of the right volume with the progression of the age. This study has described, for the first time, cardiac measurements obtained through the cardiac magnetic resonance imaging in Brazilians, asymptomatic, with no cardiomyopathies, showing differences in accordance with gender and age.

Morphological and Functional Measurements of the Heart Obtained by Magnetic Resonance Imaging in Brazilians

International Nuclear Information System (INIS)

Macedo, Robson; Fernandes, Juliano Lara; Andrade, Solange Souza; Rochitte, Carlos Eduardo; Lima, Kênio Costa; Maciel, Álvaro Campos Cavalcanti; Maciel, Fernanda Cunha; Alves, Geraldo Souza Pinho; Coelho, Otávio Rizzi; Diniz, Rosiane Viana Zuza

2013-01-01

Still today, measurements used as a reference in the cardiac magnetic resonance imaging have been obtained mainly from studies carried out in North-American and European populations. To obtain measurements of the diastolic diameter, systolic diameter, end diastolic volume, end systolic volume, ejection fraction, and myocardial mass of the left and right ventricles in Brazilians. 54 men and 53 women, with mean age of 43.4 ± 13.1 years, asymptomatic, with no cardiomyopathies, have been subjected to the cardiac magnetic resonance imaging, using a balanced steady state free precession technique. The averages and the standard deviations of the parameters for the left ventricle have been: diastolic diameter =4.8 ± 0.5 cm; systolic diameter = 3.0 ± 0.6 cm; end diastolic volume = 128.4 ± 29.6 mL; end systolic volume = 45.2 ± 16.6 mL; ejection fraction = 65.5 ± 6.3%; mass = 95.2 ± 30.8 g. For the right ventricle, they have been: diastolic diameter = 3.9 ± 1.3 cm; systolic diameter = 2.5 ± 0.5 cm; end diastolic volume = 126.5 ± 30.7 mL; end systolic volume = 53.6 ± 18.4 mL; ejection fraction = 58.3 ± 8.0%, and mass = 26.1 ± 6.1 g. The masses and the volumes were significantly greater in the men, except for the end systolic volume of the left ventricle. The ejection fraction of the right ventricle has been significantly greater in the women. There has been a significant and inverted correlation of the systolic volume of the right volume with the progression of the age. This study has described, for the first time, cardiac measurements obtained through the cardiac magnetic resonance imaging in Brazilians, asymptomatic, with no cardiomyopathies, showing differences in accordance with gender and age

Hyperbolic isometries of systolic complexes

DEFF Research Database (Denmark)

Prytula, Tomasz Pawel

The main topics of this thesis are the geometric features of systolic complexesarising from the actions of hyperbolic isometries. The thesis consists ofan introduction followed by two articles.Given a hyperbolic isometry h of a systolic complex X, our central theme isto study the minimal displace......The main topics of this thesis are the geometric features of systolic complexesarising from the actions of hyperbolic isometries. The thesis consists ofan introduction followed by two articles.Given a hyperbolic isometry h of a systolic complex X, our central theme isto study the minimal...... algebraic-topological features of systolic groups. In addition, we provide newexamples of systolic groups.In the first article we show that the minimal displacement set of a hyperbolicisometry of a systolic complex is quasi-isometric to the product of a tree andthe real line. We use this theorem...

Real-time display of flow-pressure-volume loops.

Science.gov (United States)

Morozoff, P E; Evans, R W

1992-01-01

Graphic display of respiratory waveforms can be valuable for monitoring the progress of ventilated patients. A system has been developed that can display flow-pressure-volume loops as derived from a patient's respiratory circuit in real time. It can also display, store, print, and retrieve ventilatory waveforms. Five loops can be displayed at once: current, previous, reference, "ideal," and previously saved. Two components, the data-display device (DDD) and the data-collection device (DCD), comprise the system. An IBM 286/386 computer with a graphics card (VGA) and bidirectional parallel port is used for the DDD; an eight-bit microprocessor card and an A/D convertor card make up the DCD. A real-time multitasking operating system was written to control the DDD, while the DCD operates from in-line assembly code. The DCD samples the pressure and flow sensors at 100 Hz and looks for a complete flow waveform pattern based on flow slope. These waveforms are then passed to the DDD via the mutual parallel port. Within the DDD a process integrates the flow to create a volume signal and performs a multilinear regression on the pressure, flow, and volume data to calculate the elastance, resistance, pressure offset, and coefficient of determination. Elastance, resistance, and offset are used to calculate Pr and Pc where: Pr[k] = P[k]-offset-(elastance.V[k]) and Pc[k] = P[k]-offset-(resistance.F[k]). Volume vs. Pc and flow vs. Pr can be displayed in real time. Patient data from previous clinical tests were loaded into the device to verify the software calculations. An analog waveform generator was used to simulate flow and pressure waveforms that validated the system.(ABSTRACT TRUNCATED AT 250 WORDS)

Tilting-induced decrease in systolic blood pressure in bedridden hypertensive elderly inpatients: effects of azelnidipine.

Science.gov (United States)

Morimoto, Shigeto; Takahashi, Takashi; Okaishi, Kohya; Nakahashi, Takeshi; Nomura, Kohji; Kanda, Tsugiyasu; Okuro, Masashi; Murai, Hiroshi; Nishino, Tomoichi; Matsumoto, Masayuki

2006-12-01

The object of this study was to examine blood pressure (BP) variability due to postural change in elderly hypertensive patients. The subjects studied were 154 elderly inpatients in a hospital for the elderly (48 male and 106 female; median age: 82 years), consisting of age- and sex-matched bedridden (n=39) and non-bedridden (n=39) normotensive controls and bedridden (n=38) and non-bedridden (n=38) hypertensive patients. BP and pulse rate (PR) were measured in the supine position, then again after a 2-min, 45 deg head-up tilt with the legs horizontal. The decrease in systolic BP (SBP) on tilting in the bedridden hypertensive group (median: -10 mmHg; range: -32 to 9 mmHg) was significantly (pbedridden hypertensive group. Our findings indicate that tilt-induced decrease in SBP is a rather common phenomenon in bedridden elderly hypertensive patients, and that treatment with azelnidipine attenuates tilt-induced decrease in SBP, probably through an improvement of baroreceptor sensitivity.

Changes in left ventricular systolic function in patients with chronic heart failure with preserved ejection fraction and cardiorenal anemic syndrome

Directory of Open Access Journals (Sweden)

Vasylenko V.A.

2015-09-01

Full Text Available The feature of chronic heart failure (CHF in elderly people is increasing incidence of heart failure with preserved left ventricular ejection fraction (LVEF which is associated with age. Such patients account for almost half of the total number of patients with heart failure. Cardiorenal syndrome (CRS is associated with an increased risk of mortality in patients with CHF. The impact of CRS on the structural and functional condition of the heart in these patients is studied insufficiently. The study involved 103 patients with CHF II-IV NYHA with preserved LVEF (>45% and CRS (hemoglobin <120 g/l and systolic function, namely by the increase of end-systolic volume and decrease in the degree of LV fractional shortening size.

Hemodynamic variables during exercise in childhood and resting systolic blood pressure levels 6 years later in adolescence: the European Youth Heart Study

DEFF Research Database (Denmark)

Grøntved, Anders; Andresen, Brage Storstein; Møller, N C

2011-01-01

of Danish children followed longitudinally for 6 years. The study comprised 226 children randomly sampled at age 9, who had their blood pressure and HR measured during ergometer exercise to exhaustion and was reassessed in adolescence. SBP and RPP during exercise in stage two of the test were positively......The aim of this study was to analyze whether systolic blood pressure (SBP), heart rate (HR) and rate pressure product (RPP) during exercise in childhood can predict resting SBP levels in adolescence independent of resting SBP and conventional cardiovascular risk factors. We studied this in a sample...... remained significant (P=0.059 and P=0.012, respectively). No significant independent associations were observed for HR during exercise, but associations were in the same direction. Our results supports that measuring SBP and RPP, during a standard acute ergometer exercise test in children, improves...

A Calibrated Method of Massage Therapy Decreases Systolic Blood Pressure Concomitant With Changes in Heart Rate Variability in Male Rats.

Science.gov (United States)

Spurgin, Kurt A; Kaprelian, Anthony; Gutierrez, Roberto; Jha, Vidyasagar; Wilson, Christopher G; Dobyns, Abigail; Xu, Karen H; Curras-Collazo, Margarita C

2017-02-01

The purpose of this study was to develop a method for applying calibrated manual massage pressures by using commonly available, inexpensive sphygmomanometer parts and validate the use of this approach as a quantitative method of applying massage therapy to rodents. Massage pressures were monitored by using a modified neonatal blood pressure (BP) cuff attached to an aneroid gauge. Lightly anesthetized rats were stroked on the ventral abdomen for 5 minutes at pressures of 20 mm Hg and 40 mm Hg. Blood pressure was monitored noninvasively for 20 minutes following massage therapy at 5-minute intervals. Interexaminer reliability was assessed by applying 20 mm Hg and 40 mm Hg pressures to a digital scale in the presence or absence of the pressure gauge. With the use of this method, we observed good interexaminer reliability, with intraclass coefficients of 0.989 versus 0.624 in blinded controls. In Long-Evans rats, systolic BP dropped by an average of 9.86% ± 0.27% following application of 40 mm Hg massage pressure. Similar effects were seen following 20 mm Hg pressure (6.52% ± 1.7%), although latency to effect was greater than at 40 mm Hg. Sprague-Dawley rats behaved similarly to Long-Evans rats. Low-frequency/high-frequency ratio, a widely-used index of autonomic tone in cardiovascular regulation, showed a significant increase within 5 minutes after 40 mm Hg massage pressure was applied. The calibrated massage method was shown to be a reproducible method for applying massage pressures in rodents and lowering BP. Copyright © 2016. Published by Elsevier Inc.

Infarct volume predicts critical care needs in stroke patients treated with intravenous thrombolysis

Energy Technology Data Exchange (ETDEWEB)

Faigle, Roland; Marsh, Elisabeth B.; Llinas, Rafael H.; Urrutia, Victor C. [Johns Hopkins University School of Medicine, Department of Neurology, Baltimore, MD (United States); Wozniak, Amy W. [Johns Hopkins University, Department of Biostatistics, Bloomberg School of Public Health, Baltimore, MD (United States)

2014-10-26

Patients receiving intravenous thrombolysis with recombinant tissue plasminogen activator (IVT) for ischemic stroke are monitored in an intensive care unit (ICU) or a comparable unit capable of ICU interventions due to the high frequency of standardized neurological exams and vital sign checks. The present study evaluates quantitative infarct volume on early post-IVT MRI as a predictor of critical care needs and aims to identify patients who may not require resource intense monitoring. We identified 46 patients who underwent MRI within 6 h of IVT. Infarct volume was measured using semiautomated software. Logistic regression and receiver operating characteristics (ROC) analysis were used to determine factors associated with ICU needs. Infarct volume was an independent predictor of ICU need after adjusting for age, sex, race, systolic blood pressure, NIH Stroke Scale (NIHSS), and coronary artery disease (odds ratio 1.031 per cm{sup 3} increase in volume, 95 % confidence interval [CI] 1.004-1.058, p = 0.024). The ROC curve with infarct volume alone achieved an area under the curve (AUC) of 0.766 (95 % CI 0.605-0.927), while the AUC was 0.906 (95 % CI 0.814-0.998) after adjusting for race, systolic blood pressure, and NIHSS. Maximum Youden index calculations identified an optimal infarct volume cut point of 6.8 cm{sup 3} (sensitivity 75.0 %, specificity 76.7 %). Infarct volume greater than 3 cm{sup 3} predicted need for critical care interventions with 81.3 % sensitivity and 66.7 % specificity. Infarct volume may predict needs for ICU monitoring and interventions in stroke patients treated with IVT. (orig.)

Infarct volume predicts critical care needs in stroke patients treated with intravenous thrombolysis

International Nuclear Information System (INIS)

Faigle, Roland; Marsh, Elisabeth B.; Llinas, Rafael H.; Urrutia, Victor C.; Wozniak, Amy W.

2015-01-01

Patients receiving intravenous thrombolysis with recombinant tissue plasminogen activator (IVT) for ischemic stroke are monitored in an intensive care unit (ICU) or a comparable unit capable of ICU interventions due to the high frequency of standardized neurological exams and vital sign checks. The present study evaluates quantitative infarct volume on early post-IVT MRI as a predictor of critical care needs and aims to identify patients who may not require resource intense monitoring. We identified 46 patients who underwent MRI within 6 h of IVT. Infarct volume was measured using semiautomated software. Logistic regression and receiver operating characteristics (ROC) analysis were used to determine factors associated with ICU needs. Infarct volume was an independent predictor of ICU need after adjusting for age, sex, race, systolic blood pressure, NIH Stroke Scale (NIHSS), and coronary artery disease (odds ratio 1.031 per cm 3 increase in volume, 95 % confidence interval [CI] 1.004-1.058, p = 0.024). The ROC curve with infarct volume alone achieved an area under the curve (AUC) of 0.766 (95 % CI 0.605-0.927), while the AUC was 0.906 (95 % CI 0.814-0.998) after adjusting for race, systolic blood pressure, and NIHSS. Maximum Youden index calculations identified an optimal infarct volume cut point of 6.8 cm 3 (sensitivity 75.0 %, specificity 76.7 %). Infarct volume greater than 3 cm 3 predicted need for critical care interventions with 81.3 % sensitivity and 66.7 % specificity. Infarct volume may predict needs for ICU monitoring and interventions in stroke patients treated with IVT. (orig.)

Volume-monitored chest CT: a simplified method for obtaining motion-free images near full inspiratory and end expiratory lung volumes

Energy Technology Data Exchange (ETDEWEB)

Mueller, Kathryn S. [The Ohio State University College of Medicine, Columbus, OH (United States); Long, Frederick R. [Nationwide Children' s Hospital, The Children' s Radiological Institute, Columbus, OH (United States); Flucke, Robert L. [Nationwide Children' s Hospital, Department of Pulmonary Medicine, Columbus, OH (United States); Castile, Robert G. [The Research Institute at Nationwide Children' s Hospital, Center for Perinatal Research, Columbus, OH (United States)

2010-10-15

Lung inflation and respiratory motion during chest CT affect diagnostic accuracy and reproducibility. To describe a simple volume-monitored (VM) method for performing reproducible, motion-free full inspiratory and end expiratory chest CT examinations in children. Fifty-two children with cystic fibrosis (mean age 8.8 {+-} 2.2 years) underwent pulmonary function tests and inspiratory and expiratory VM-CT scans (1.25-mm slices, 80-120 kVp, 16-40 mAs) according to an IRB-approved protocol. The VM-CT technique utilizes instruction from a respiratory therapist, a portable spirometer and real-time documentation of lung volume on a computer. CT image quality was evaluated for achievement of targeted lung-volume levels and for respiratory motion. Children achieved 95% of vital capacity during full inspiratory imaging. For end expiratory scans, 92% were at or below the child's end expiratory level. Two expiratory exams were judged to be at suboptimal volumes. Two inspiratory (4%) and three expiratory (6%) exams showed respiratory motion. Overall, 94% of scans were performed at optimal volumes without respiratory motion. The VM-CT technique is a simple, feasible method in children as young as 4 years to achieve reproducible high-quality full inspiratory and end expiratory lung CT images. (orig.)

Left ventricular dimensions, systolic functions, and mass in term neonates with symmetric and asymmetric intrauterine growth restriction.

Science.gov (United States)

Cinar, Bahar; Sert, Ahmet; Gokmen, Zeynel; Aypar, Ebru; Aslan, Eyup; Odabas, Dursun

2015-02-01

Previous studies have demonstrated structural changes in the heart and cardiac dysfunction in foetuses with intrauterine growth restriction. There are no available data that evaluated left ventricular dimensions and mass in neonates with symmetric and asymmetric intrauterine growth restriction. Therefore, we aimed to evaluate left ventricular dimensions, systolic functions, and mass in neonates with symmetric and asymmetric intrauterine growth restriction. We also assessed associated maternal risk factors, and compared results with healthy appropriate for gestational age neonates. In all, 62 asymmetric intrauterine growth restriction neonates, 39 symmetric intrauterine growth restriction neonates, and 50 healthy appropriate for gestational age neonates were evaluated by transthoracic echocardiography. The asymmetric intrauterine growth restriction group had significantly lower left ventricular end-systolic and end-diastolic diameters and posterior wall diameter in systole and diastole than the control group. The symmetric intrauterine growth restriction group had significantly lower left ventricular end-diastolic diameter than the control group. All left ventricular dimensions were lower in the asymmetric intrauterine growth restriction neonates compared with symmetric intrauterine growth restriction neonates (p>0.05), but not statistically significant except left ventricular posterior wall diameter in diastole (3.08±0.83 mm versus 3.54 ±0.72 mm) (pintrauterine growth restriction groups had significantly lower relative posterior wall thickness (0.54±0.19 versus 0.48±0.13 versus 0.8±0.12), left ventricular mass (9.8±4.3 g versus 8.9±3.4 g versus 22.2±5.7 g), and left ventricular mass index (63.6±29.1 g/m2 versus 54.5±24.4 g/m2 versus 109±28.8 g/m2) when compared with the control group. Our study has demonstrated that although neonates with both symmetric and asymmetric intrauterine growth restriction had lower left ventricular dimensions, relative

Lower Protein-to-Carbohydrate Ratio in Maternal Diet is Associated with Higher Childhood Systolic Blood Pressure up to Age Four Years

Directory of Open Access Journals (Sweden)

Michelle L. Blumfield

2015-04-01

Full Text Available The prenatal environment can influence development of offspring blood pressure (BP, which tracks into adulthood. This prospective longitudinal study investigated whether maternal pregnancy dietary intake is associated with the development of child BP up to age four years. Data are from 129 mother-child dyads enrolled in the Women and Their Children’s Health study. Maternal diet was assessed using a validated 74-item food frequency questionnaire at 18 to 24 weeks and 36 to 40 weeks, with a reference period of the previous three months. Child systolic and diastolic BP were measured at 3, 6, 9, 12, 24, 36 and 48 months, using an automated BP monitor. Using mixed-model regression analyses adjusted for childhood growth indices, pregnancy intakes of percentage of energy (E% polyunsaturated fat (β coefficient 0.73; 95% CI 0.003, 1.45; p = 0.045, E% omega-6 fatty acids (β coefficient 0.89; 95% CI 0.09, 1.69; p = 0.03 and protein-to-carbohydrate (P:C ratio (β coefficient −14.14; 95% CI −27.68, −0.60; p = 0.04 were associated with child systolic BP trajectory up to 4 years. Child systolic BP was greatest at low proportions of dietary protein (<16% of energy and high carbohydrate (>40% of energy intakes. There may be an ideal maternal macronutrient ratio associated with optimal infant BP. Maternal diet, which is potentially modifiable, may play an important role in influencing offspring risk of future hypertension.

Forward coronary flow normally seen in systole is the result of both forward and concealed back flow

NARCIS (Netherlands)

Spaan, J. A.; Breuls, N. P.; Laird, J. D.

1981-01-01

Normally systolic coronary blood flow is almost entirely forward. As perfusion pressure was lowered through the autoregulatory range in open-chest dogs, net systolic back flow appeared at approximately 70 mm Hg. Imposing a series resistance (Rs), which impedes both forward and back flow, abolished

Acute changes in pulse pressure in relation to constituents of particulate air pollution in elderly persons

Energy Technology Data Exchange (ETDEWEB)

Jacobs, Lotte [Occupational and Environmental Medicine, Unit of Lung Toxicology, K.U.Leuven, Leuven (Belgium); Buczynska, Anna [Departement of Chemistry, UA, Wilrijk (Belgium); Walgraeve, Christophe [Research group EnVOC, Department of Sustainable Organic Chemistry and Technology, UGent, Gent (Belgium); Delcloo, Andy [Royal Meteorological Institute, Brussels (Belgium); Potgieter-Vermaak, Sanja [Departement of Chemistry, UA, Wilrijk (Belgium); Molecular Science Institute, School of Chemistry, University of Witwatersrand, Johannesburg (South Africa); Division of Chemistry and Environmental Science, Manchester Metropolitan University, Manchester (United Kingdom); Van Grieken, Rene [Departement of Chemistry, UA, Wilrijk (Belgium); Demeestere, Kristof; Dewulf, Jo; Van Langenhove, Herman [Research group EnVOC, Department of Sustainable Organic Chemistry and Technology, UGent, Gent (Belgium); De Backer, Hugo [Royal Meteorological Institute, Brussels (Belgium); Nemery, Benoit, E-mail: ben.nemery@med.kuleuven.be [Occupational and Environmental Medicine, Unit of Lung Toxicology, K.U.Leuven, Leuven (Belgium); Nawrot, Tim S. [Occupational and Environmental Medicine, Unit of Lung Toxicology, K.U.Leuven, Leuven (Belgium); Centre for Environmental Sciences, Hasselt University, Diepenbeek (Belgium)

2012-08-15

An increased pulse pressure (difference between systolic and diastolic blood pressure) suggests aortic stiffening. The objective of this study was to examine the acute effects of both particulate matter (PM) mass and composition on blood pressure, among elderly persons. We carried out a panel study in persons living in elderly homes in Antwerp, Belgium. We recruited 88 non-smoking persons, 70% women with a mean age of 83 years (standard deviation: 5.2). Blood pressure was measured and a blood sample was collected on two time points, which were chosen so that there was an exposure contrast in ambient PM exposure. The elemental content of the collected indoor and outdoor PM{sub 2.5} (particulate matter with an aerodynamic diameter <2.5 {mu}m) mass concentration was measured. Oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs) on outdoor PM{sub 10} (particulate matter with an aerodynamic diameter <10 {mu}m) were measured. Each interquartile range increase of 20.8 {mu}g/m Superscript-Three in 24-h mean outdoor PM{sub 2.5} was associated with an increase in pulse pressure of 4.0 mmHg (95% confidence interval: 1.8-6.2), in persons taking antihypertensive medication (n=57), but not in persons not using antihypertensive medication (n=31) (p for interaction: 0.02). Vanadium, iron and nickel contents of PM{sub 2.5} were significantly associated with systolic blood pressure and pulse pressure, among persons on antihypertensive medication. Similar results were found for indoor concentrations. Of the oxy-PAHs, chrysene-5,6-dione and benzo[a]pyrene-3,6-dione were significantly associated with increases in systolic blood pressure and pulse pressure. In elderly, pulse pressure was positively associated with acute increases in outdoor and indoor air pollution, among persons taking antihypertensive medication. These results might form a mechanistic pathway linking air pollution as a trigger of cardiovascular events.

Prevalence of end-digit preference in recorded blood pressure by ...

African Journals Online (AJOL)

2012-03-15

Mar 15, 2012 ... (BP) measuring device eliminates the risk of exposure to mercury. ... Results: There was a large and significant fall in end-digit zero when BP readings that were ..... positioning, an inadequate rest period and the posture of the .... electronic blood pressure measurement influence recorded blood pressure?

Gene-centric meta-analysis in 87,736 individuals of European ancestry identifies multiple blood-pressure-related loci

NARCIS (Netherlands)

Tragante, Vinicius; Barnes, Michael R; Ganesh, Santhi K; Lanktree, Matthew B; Guo, Wei; Franceschini, Nora; Smith, Erin N; Johnson, Toby; Holmes, Michael V; Padmanabhan, Sandosh; Karczewski, Konrad J; Almoguera, Berta; Barnard, John; Baumert, Jens; Chang, Yen-Pei Christy; Elbers, Clara C; Farrall, Martin; Fischer, Mary E; Gaunt, Tom R; Gho, Johannes M I H; Gieger, Christian; Goel, Anuj; Gong, Yan; Isaacs, Aaron; Kleber, Marcus E; Mateo Leach, Irene; McDonough, Caitrin W; Meijs, Matthijs F L; Melander, Olle; Nelson, Christopher P; Nolte, Ilja M; Pankratz, Nathan; Price, Tom S; Shaffer, Jonathan; Shah, Sonia; Tomaszewski, Maciej; van der Most, Peter J; Van Iperen, Erik P A; Vonk, Judith M; Witkowska, Kate; Wong, Caroline O L; Zhang, Li; Beitelshees, Amber L; Berenson, Gerald S; Bhatt, Deepak L; Brown, Morris; Burt, Amber; Cooper-DeHoff, Rhonda M; Connell, John M; Cruickshanks, Karen J; Curtis, Sean P; Davey-Smith, George; Delles, Christian; Gansevoort, Ron T; Guo, Xiuqing; Haiqing, Shen; Hastie, Claire E; Hofker, Marten H; Hovingh, G Kees; Kim, Daniel S; Kirkland, Susan A; Klein, Barbara E; Klein, Ronald; Li, Yun R; Maiwald, Steffi; Newton-Cheh, Christopher; O'Brien, Eoin T; Onland-Moret, N Charlotte; Palmas, Walter; Parsa, Afshin; Penninx, Brenda W; Pettinger, Mary; Vasan, Ramachandran S; Ranchalis, Jane E; M Ridker, Paul; Rose, Lynda M; Sever, Peter; Shimbo, Daichi; Steele, Laura; Stolk, Ronald P; Thorand, Barbara; Trip, Mieke D; van Duijn, Cornelia M; Verschuren, W Monique; Wijmenga, Cisca; Wyatt, Sharon; Young, J Hunter; Zwinderman, Aeilko H; Bezzina, Connie R; Boerwinkle, Eric; Casas, Juan P; Caulfield, Mark J; Chakravarti, Aravinda; Chasman, Daniel I; Davidson, Karina W; Doevendans, Pieter A; Dominiczak, Anna F; FitzGerald, Garret A; Gums, John G; Fornage, Myriam; Hakonarson, Hakon; Halder, Indrani; Hillege, Hans L; Illig, Thomas; Jarvik, Gail P; Johnson, Julie A; Kastelein, John J P; Koenig, Wolfgang; Kumari, Meena; März, Winfried; Murray, Sarah S; O'Connell, Jeffery R; Oldehinkel, Albertine J; Pankow, James S; Rader, Daniel J; Redline, Susan; Reilly, Muredach P; Schadt, Eric E; Kottke-Marchant, Kandice; Snieder, Harold; Snyder, Michael; Stanton, Alice V; Tobin, Martin D; Uitterlinden, André G; van der Harst, Pim; van der Schouw, Yvonne T; Samani, Nilesh J; Watkins, Hugh; Johnson, Andrew D; Reiner, Alex P; Zhu, Xiaofeng; de Bakker, Paul I W; Levy, Daniel; Asselbergs, Folkert W; Munroe, Patricia B; Keating, Brendan J

2014-01-01

Blood pressure (BP) is a heritable risk factor for cardiovascular disease. To investigate genetic associations with systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and pulse pressure (PP), we genotyped similar to 50,000 SNPs in up to 87,736 individuals of European ancestry and

Gene-centric meta-analysis in 87,736 individuals of European ancestry identifies multiple blood-pressure-related loci

NARCIS (Netherlands)

V. Tragante (Vinicius); M.J. Barnes (Michael); S.K. Ganesh (Santhi); M.B. Lanktree (Matthew); W. Guo (Weixiang); N. Franceschini (Nora); G.D. Smith; T. Johnson (Toby); M.V. Holmes (Michael); S. Padmanabhan (Sandosh); K.J. Karczewski (Konrad); B. Almoguera (Berta); J. Barnard (John); J. Baumert (Jens); Y.-P.C. Chang (Yen-Pei); C.C. Elbers (Clara); M. Farrall (Martin); M.E. Fischer (Mary); T.R. Gaunt (Tom); J.M.I.H. Gho (Johannes); C. Gieger (Christian); A. Goel (Anuj); Y. Gong (Yeming); A.J. Isaacs (Aaron); M.E. Kleber (Marcus); I.M. Leach (Irene Mateo); C.W. McDonough (Caitrin); M.F.L. Meijs (Matthijs); O. Melander (Olle); C.P. Nelson (Christopher P.); I.M. Nolte (Ilja); V.S. Pankratz (Shane); T.S. Price (Thomas); J. Shaffer (Jonathan); S. Shah (Sonia); M. Tomaszewski (Maciej); P.J. van der Most (Peter); E.P.A. van Iperen (Erik); J.M. Vonk (Judith); H.E. Witkowska (Ewa); C.O.L. Wong (Caroline); L. Zhang (Lingling); A.L. Beitelshees (Amber); G. Berenson (Gerald); D.L. Bhatt (Deepak); M.J. Brown (Morris); A.D. Burt (Alastair); R.M. Cooper-Dehoff (Rhonda); J. Connell (John); K.J. Cruickshanks (Karen); S.P. Curtis (Sean); G. Davey-Smith (George); C. Delles (Christian); R.T. Gansevoort (Ron); X. Guo (Xiuqing); S. Haiqing (Shen); C.E. Hastie (Claire); M.A. Hofker (Marten); G.K. Hovingh (Kees); D.S. Kim (Daniel); S.A. Kirkland (Susan); B.E.K. Klein (Barbara); B.E.K. Klein (Barbara); Y.R. Li (Yun); R. Maiwald (Robert); C. Newton-Cheh (Christopher); E. O'Brien (Eoin); N.C. Onland-Moret (Charlotte); W. Palmas (Walter); A. Parsa (Afshin); B.W.J.H. Penninx (Brenda); M. Pettinger (Mary); R.S. Vasan (Ramachandran Srini); J.E. Ranchalis (Jane); P. M Ridker (Paul); L.M. Rose (Lynda); P. Sever (Peter); D. Shimbo (Daichi); L. Steele (Linda); R.P. Stolk (Ronald); B. Thorand (Barbara); M.D. Trip (Mieke); C.M. van Duijn (Cornelia); W.M.M. Verschuren (W. M. Monique); C. Wijmenga (Cisca); S. Wyatt (Sally); J.C. Young (J. C.); A.H. Zwinderman (Ailko); C.R. Bezzina (Connie); E.A. Boerwinkle (Eric); J.P. Casas (Juan); M. Caulfield (Mark); A. Chakravarti (Aravinda); D.I. Chasman (Daniel); K.W. Davidson (Karina); P.A. Doevendans (Pieter); A. Dominiczak (Anna); G.A. Fitzgerald (Garret); J.G. Gums (John); M. Fornage (Myriam); H. Hakonarson (Hakon); H. van Halder (Han); H.L. Hillege (Hans); T. Illig (Thomas); G.P. Jarvik (Gail); J.A. Johnson (Jennifer ); J.J.P. Kastelein (John); W. Koenig (Wolfgang); M. Kumari (Meena); W. März (Winfried); S.S. Murray (Sarah); J.R. O'Connell (Jeffery); A.J. Oldehinkel (Albertine); J.S. Pankow (James); D.J. Rader (Daniel); S. Redline (Susan); M.P. Reilly (Muredach); E.E. Schadt (Eric); K. Kottke-Marchant (Kandice); H. Snieder (Harold); M. Snyder (Michael); A. Stanton (Alice); M.D. Tobin (Martin); A.G. Uitterlinden (André); P. van der Harst (Pim); Y.T. van der Schouw (Yvonne); N.J. Samani (Nilesh); H. Watkins (Hugh); A.D. Johnson (Andrew); A.P. Reiner (Alex); X. Zhu (Xiaofeng); P.I.W. de Bakker (Paul); D. Levy (Daniel); F.W. Asselbergs (Folkert); P. Munroe (Patricia); J. Keating (John)

2014-01-01

textabstractBlood pressure (BP) is a heritable risk factor for cardiovascular disease. To investigate genetic associations with systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and pulse pressure (PP), we genotyped ∼50,000 SNPs in up to 87,736 individuals of European ancestry and

Gene-centric meta-analysis in 87,736 individuals of European ancestry identifies multiple blood-pressure-related loci

NARCIS (Netherlands)

Tragante, Vinicius; Barnes, Michael R.; Ganesh, Santhi K.; Lanktree, Matthew B.; Guo, Wei; Franceschini, Nora; Smith, Erin N.; Johnson, Toby; Holmes, Michael V.; Padmanabhan, Sandosh; Karczewski, Konrad J.; Almoguera, Berta; Barnard, John; Baumert, Jens; Chang, Yen-Pei Christy; Elbers, Clara C.; Farrall, Martin; Fischer, Mary E.; Gaunt, Tom R.; Gho, Johannes M. I. H.; Gieger, Christian; Goel, Anuj; Gong, Yan; Isaacs, Aaron; Kleber, Marcus E.; Mateo Leach, Irene; McDonough, Caitrin W.; Meijs, Matthijs F. L.; Melander, Olle; Nelson, Christopher P.; Nolte, Ilja M.; Pankratz, Nathan; Price, Tom S.; Shaffer, Jonathan; Shah, Sonia; Tomaszewski, Maciej; van der Most, Peter J.; van Iperen, Erik P. A.; Vonk, Judith M.; Witkowska, Kate; Wong, Caroline O. L.; Zhang, Li; Beitelshees, Amber L.; Berenson, Gerald S.; Bhatt, Deepak L.; Brown, Morris; Burt, Amber; Cooper-DeHoff, Rhonda M.; Connell, John M.; Cruickshanks, Karen J.; Curtis, Sean P.; Davey-Smith, George; Delles, Christian; Gansevoort, Ron T.; Guo, Xiuqing; Haiqing, Shen; Hastie, Claire E.; Hofker, Marten H.; Hovingh, G. Kees; Kim, Daniel S.; Kirkland, Susan A.; Klein, Barbara E.; Klein, Ronald; Li, Yun R.; Maiwald, Steffi; Newton-Cheh, Christopher; O'Brien, Eoin T.; Onland-Moret, N. Charlotte; Palmas, Walter; Parsa, Afshin; Penninx, Brenda W.; Pettinger, Mary; Vasan, Ramachandran S.; Ranchalis, Jane E.; M Ridker, Paul; Rose, Lynda M.; Sever, Peter; Shimbo, Daichi; Steele, Laura; Stolk, Ronald P.; Thorand, Barbara; Trip, Mieke D.; van Duijn, Cornelia M.; Verschuren, W. Monique; Wijmenga, Cisca; Wyatt, Sharon; Young, J. Hunter; Zwinderman, Aeilko H.; Bezzina, Connie R.; Boerwinkle, Eric; Casas, Juan P.; Caulfield, Mark J.; Chakravarti, Aravinda; Chasman, Daniel I.; Davidson, Karina W.; Doevendans, Pieter A.; Dominiczak, Anna F.; FitzGerald, Garret A.; Gums, John G.; Fornage, Myriam; Hakonarson, Hakon; Halder, Indrani; Hillege, Hans L.; Illig, Thomas; Jarvik, Gail P.; Johnson, Julie A.; Kastelein, John J. P.; Koenig, Wolfgang; Kumari, Meena; März, Winfried; Murray, Sarah S.; O'Connell, Jeffery R.; Oldehinkel, Albertine J.; Pankow, James S.; Rader, Daniel J.; Redline, Susan; Reilly, Muredach P.; Schadt, Eric E.; Kottke-Marchant, Kandice; Snieder, Harold; Snyder, Michael; Stanton, Alice V.; Tobin, Martin D.; Uitterlinden, André G.; van der Harst, Pim; van der Schouw, Yvonne T.; Samani, Nilesh J.; Watkins, Hugh; Johnson, Andrew D.; Reiner, Alex P.; Zhu, Xiaofeng; de Bakker, Paul I. W.; Levy, Daniel; Asselbergs, Folkert W.; Munroe, Patricia B.; Keating, Brendan J.

2014-01-01

Blood pressure (BP) is a heritable risk factor for cardiovascular disease. To investigate genetic associations with systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and pulse pressure (PP), we genotyped ~50,000 SNPs in up to 87,736 individuals of European ancestry and combined

Prevalence of high blood pressure subtypes and its associations with BMI in Chinese children: a national cross-sectional survey.

Science.gov (United States)