Clinical studies on hemodynamic assessments of valvular heart disease by means of radiopulmonary cardiography (RPCG)

International Nuclear Information System (INIS)

Doi, Shuji

1978-01-01

Radiopulmonary cardiography and lung scinti-scanning methods were employed for this study and performed on 59 patients with mitral valve disease and on 6 patients with aortic valve disease. For these examination, sup(99m)Tc-Pertechnetate and 131 I-MAA were administered intravenously as usual. Circulation time from the right heart to the lung (R-P), and from the lung to the left heart (P-L), and from the right heart to the left heart (R-L), as well as the value to the R-P and P-L ratio, and the U/L ratio in terms of blood distribution in the upper and lower parts of the lung were carefully estimated through these methods. Significant prolongation of the P-L interval and decrease in the R-P/P-L ratio were clearly observed in aortic insufficiency, mitral insufficiency, mitral stnosis, and mitral steno-insufficiency (MSI). On the contrary, prolongation of the R-P interval and an increase in the R-P/P-L ratio were recognized in patients with MSI + tricuspid insufficiency (TI). Radiopulmonary cardiograms revealed such characteristic patterns in each valvular heart disease, that differential diagnosis among valvular heart disease could be confirmed. The R-L interval was over 16 seconds in patients with MSI + TI who developed cardiac failure. The more the R-L interval was prolonged, the more severe the cardiac failure was found to be. A significant prolongation of the R-P interval and an increase in the R-P/P-L ratio, as well as a slight increase in the U/L ratio were clarly observed in the cases with severe right cardiac failure due to TI. On the other hand, remarked prolongation of the P-L interval, and a low value in the R-P/P-L ratio, as well as high value in the U/L ratio were seen in the cases with left cardiac failure. From these findings, the degree of severity and location of cardiac failure or of TI could be approximately evaluated. (author)

Principios de la evaluación hemodinámica no invasiva con cardiografía de impedancia Principles of non-invasive hemodynamic assessment with impedance cardiography

Directory of Open Access Journals (Sweden)

Juan E Ochoa M

2009-06-01

Full Text Available La cardiografía de impedancia es una técnica no invasiva que permite una determinación rápida, continua y reproducible del gasto cardiaco latido a latido. Mide los cambios en la resistencia eléctrica del tórax que se producen por las variaciones en el volumen sanguíneo en la aorta durante el ciclo cardiaco. La medición continua del cambio en la impedancia o las fluctuaciones del volumen sanguíneo durante la sístole y la diástole, permite determinar el volumen latido, el gasto cardiaco, la contractilidad miocárdica y el contenido total de fluido del tórax. Entre las ventajas de esta técnica se incluyen su fácil implementación y asequibilidad, así como la posibilidad de ser realizada por prácticamente cualquier miembro del equipo de salud. La precisión de la cardiografía de impedancia ha sido validada en numerosos estudios en diferentes escenarios clínicos: hipertensión arterial, falla cardiaca, hipertensión pulmonar, optimización de la terapia de resincronización cardiaca y en pacientes críticos, situaciones en las que provee información sobre el estado hemodinámico sin los riesgos de otras técnicas invasivas o mínimamente invasivas. Es además un método de fácil aplicación y costo-efectivo para el diagnóstico y seguimiento de la respuesta a las intervenciones terapéuticas en múltiples patologías. La técnica representa así un cambio en los paradigmas del monitoreo hemodinámico.Impedance cardiography (ICG is a non-invasive technique that allows a rapid, continuous and reproducible beat-to-beat cardiac output estimation. This technique measures thoracic electrical resistance changes produced by variations in the blood volume in the aorta during the cardiac cycle. Continuous measurement of impedance changes or fluctuations of blood volume during systole and diastole allow the determination of stroke volume, cardiac output, myocardial contractility, and total thoracic fluid content. Between the advantages of

Impedance cardiography

NARCIS (Netherlands)

Lamberts, Robert

1984-01-01

De doelstelling van dit onderzoek over impedantie-cardiograflie was het vaststellen van de bruikbaarheid van deze voor NASA ontwikkelde niet-invasieve meetmethode, in het bijzonder voor het bepalen van het slagvolume van de linker hartkamer. ... Zie: Samenvatting

Impedance cardiography: Pulsatile blood flow and the biophysical and electrodynamic basis for the stroke volume equations

Directory of Open Access Journals (Sweden)

Donald P Bernstein

2010-01-01

Full Text Available Impedance cardiography (ICG is a branch of bioimpedance pimarily concerned with the determination of left ventricular stroke volume (SV. As implemented, using the transthoracic approach, the technique involves applying a current field longitudinally across a segment of thorax by means of a constant magnitude, high frequency, low amplitude alternating current (AC. By Ohm's Law, the voltage difference measured within the current field is proportional to the electrical impedance Z (Ω. Without ventilatory or cardiac activity, Z is known as the transthoracic, static base impedance Z0. Upon ventricular ejection, a characteristic time dependent cardiac-synchronous pulsatile impedance change is obtained, ΔZ(t, which, when placed electrically in parallel with Z0, constitutes the time-variable total transthoracic impedance Z(t. ΔZ(t represents a dual-element composite waveform, which comprises both the radially-oriented volumetric expansion of and axially-directed forward blood flow within both great thoracic arteries. In its majority, however, ΔZ(t is known to primarily emanate from the ascending aorta. Conceptually, commonly implemented methods assume a volumetric origin for the peak systolic upslope of ΔZ(t, (i.e. dZ/dtmax, with the presumed units of Ω·s-1. A recently introduced method assumes the rapid ejection of forward flowing blood in earliest systole causes significant changes in the velocity-induced blood resistivity variation (Δρb(t, Ωcm·s-1, and it is the peak rate of change of the blood resistivity variation dρb(t/dtmax (Ωcm·s-2 that is the origin of dZ/dtmax. As a consequence of dZ/dtmax peaking in the time domain of peak aortic blood acceleration, dv/dtmax (cm·s-2, it is suggested that dZ/dtmax is an ohmic mean acceleration analog (Ω·s-2 and not a mean flow or velocity surrogate as generally assumed. As conceptualized, the normalized value, dZ/dtmax/Z0, is a dimensionless ohmic mean acceleration equivalent (s-2

[Current status of noninvasive hemodynamics in hypertension].

Science.gov (United States)

Waisman, G

Hypertension is a haemodynamic disorder resulting from a persistent mismatch between cardiac output and peripheral resistance. Hypertension undergoes haemodynamic progression during its natural history. Impedance cardiography is a method of evaluating the cardiovascular system that obtains haemodynamic information from beat to beat through the analysis of variations in the impedance of the thorax on the passage of an electric current. Impedance cardiography unmasks the haemodynamic deterioration underlying the increase in blood pressure as age and systolic blood pressure increases. This method may help to improve blood pressure control through individualized treatment with reduction of peripheral resistance, maintenance of cardiac output or its increase, improvement of arterial compliance and preservation of organ-tissue perfusion. It is useful in the management of patients with resistant hypertension, since a greater percentage of patients controlled with changes in the treatment in relation to the haemodynamic measurements are obtained. Impedance cardiography is important and has prognostic utility in relation to a haemodynamic deterioration pattern and increased cardiovascular events. Copyright © 2017 SEH-LELHA. Publicado por Elsevier España, S.L.U. All rights reserved.

Radionuclide cardiography in medical practice

International Nuclear Information System (INIS)

Strangfeld, D.; Mohnike, W.; Schmidt, J.; Heine, H.; Correns, H.J.

1986-01-01

This publication is a compendium on all aspects of radionuclide diagnostics concerning cardiovascular system diseases. Starting with introductory remarks on the control of cardiovascular diseases the contribution of radionuclide cardiology to functional cardiovascular diagnostics as well as pathophysiological and pathobiochemical aspects of radiocardiography are outlined. Radiopharmaceuticals used in radiocardiography, physical and technical problems in application of radionuclides and their measuring techniques are discussed. In individual chapters radionuclide ventriculography, myocardial scintiscanning, circulatory diagnostics, radionuclide diagnostics of arterial hypertension, of thrombosis and in vitro diagnostics of thrombophilia are treated in the framework of clinical medicine

Anthracycline-induced cardiotoxicity. Changes in left ventricular function evaluated by radionuclide cardiography during and after epirubicin therapy and predictive value of the method for heart failure; Antracyclin-induceret kardiotoxicitet. Aendringer i venstre ventrikels funktion vurderet ved isotopkardiografi under og efter behandling med epirubicin, og metodens evne til at praediktere klinisk hjerteinsufficiens

Energy Technology Data Exchange (ETDEWEB)

Schaadt, Bente Krogsgaard

1998-12-31

Eighty-nine patients with breast cancer participated in this study of the left ventricular function determined by radionuclide cardiography before, during and after epirubicin treatment. Radiocardiography (MUGA = MUlti Gated Acquisition) was performed on patients in horizontal position after an intravenous injection of {sup 99m}Tc-labelled human serum albumin. Of these patients 67 were treated with at least 850 mg/m{sup 2} of the drug. Eight of the patients developed clinical signs of heart failure, whereas 59 did not. A fall in left ventricular ejection fraction (LVEF) was recorded during the first of the treatment period in both groups. The age was significantly higher and LVEF lower before epirubicin treatment in the group that developed heart failure, but the change in LVEF during treatment was of the same magnitude in the two groups. Whereas internationally recommended criteria for interruption of chemotherapy had low predictive values in these patients, a combination of 3 criteria: age {>=} 50 years, pre-treatment LVEF {<=} 0.60 and a fall in LVEF below 0.50 during epirubicin treatment yielded a high diagnostic value with regard to development of heart failure. The sensitivity and specificity of these criteria were 88% and 95%, respectively, and the predictive value of a positive and a negative test 70% and 98%. (au)

Haemodynamic changes following treatment of subclinical and overt hyperthyroidism

DEFF Research Database (Denmark)

Faber, J; Wiinberg, N; Schifter, S

2001-01-01

rate. Subclinical hyperthyroidism is characterised by reduced serum TSH levels despite free thyroxine (T4) and tri-iodothyronine (T3) estimates within the reference range, in subjects with no obvious symptoms of hyperthyroidism. We measured haemodynamic changes (using impedance cardiography...

Erythrocyte orientation and lung conductivity analysis with a high temporal resolution FEM model for bioimpedance measurements

NARCIS (Netherlands)

Ulbrich, M.; Paluchowski, P.; Muehlsteff, J.; Leonhardt, S.

2012-01-01

Impedance cardiography (ICG) is a simple and cheap method to acquirehemodynamic parameters. In this work, the influence of three dynamic physiological sources has been analyzed using a model of the humanthorax with a high temporal resolution. Therefore, simulations havebeen conducted using the

Hemodynamic changes after levothyroxine treatment in subclinical hypothyroidism

DEFF Research Database (Denmark)

Faber, J; Petersen, L; Wiinberg, N

2002-01-01

] despite free thyroxine [T(4)] and triiodothyronine [T(3)] estimates within reference range) would benefit from levothyroxine (LT(4)) substitution. CO was measured by impedance cardiography, which is an observer independent method with high precision, and mean arterial pressure (MAP) by oscillometry. SVR...

Wavelet analysis of the impedance cardiogram waveforms

Science.gov (United States)

Podtaev, S.; Stepanov, R.; Dumler, A.; Chugainov, S.; Tziberkin, K.

2012-12-01

Impedance cardiography has been used for diagnosing atrial and ventricular dysfunctions, valve disorders, aortic stenosis, and vascular diseases. Almost all the applications of impedance cardiography require determination of some of the characteristic points of the ICG waveform. The ICG waveform has a set of characteristic points known as A, B, E ((dZ/dt)max) X, Y, O and Z. These points are related to distinct physiological events in the cardiac cycle. Objective of this work is an approbation of a new method of processing and interpretation of the impedance cardiogram waveforms using wavelet analysis. A method of computer thoracic tetrapolar polyrheocardiography is used for hemodynamic registrations. Use of original wavelet differentiation algorithm allows combining filtration and calculation of the derivatives of rheocardiogram. The proposed approach can be used in clinical practice for early diagnostics of cardiovascular system remodelling in the course of different pathologies.

Wavelet analysis of the impedance cardiogram waveforms

International Nuclear Information System (INIS)

Podtaev, S; Stepanov, R; Dumler, A; Chugainov, S; Tziberkin, K

2012-01-01

Impedance cardiography has been used for diagnosing atrial and ventricular dysfunctions, valve disorders, aortic stenosis, and vascular diseases. Almost all the applications of impedance cardiography require determination of some of the characteristic points of the ICG waveform. The ICG waveform has a set of characteristic points known as A, B, E ((dZ/dt) max ) X, Y, O and Z. These points are related to distinct physiological events in the cardiac cycle. Objective of this work is an approbation of a new method of processing and interpretation of the impedance cardiogram waveforms using wavelet analysis. A method of computer thoracic tetrapolar polyrheocardiography is used for hemodynamic registrations. Use of original wavelet differentiation algorithm allows combining filtration and calculation of the derivatives of rheocardiogram. The proposed approach can be used in clinical practice for early diagnostics of cardiovascular system remodelling in the course of different pathologies.

Quantitative Radio-Cardiography with the Digital Autofluoroscope

Energy Technology Data Exchange (ETDEWEB)

Bender, M. A.; Moussa-Mahmoud, L.; Blau, M. [Roswell Park Memorial Institute, Buffalo, NY (United States)

1969-05-15

The Digital Autofluoroscope was designed primarily to permit a quantitative evaluation of the rapid flow of short-lived radioisotopes through compartments within organs. To perform these studies, the instrument is operated in the dynamic mode. In this mode the patient is positioned in front of the detector, the radioactive material is administered, and the instrument automatically accumulates data in a magnetic core memory for a preset period of time varying from 30 milliseconds to 1 minute. At the end of the accumulation period, the stored information is dumped on computer-compatible digital magnetictape, the memory is cleared, and a new accumulation cycle commences. Upon completion of a study, the tape is replayed and anatomical sites identified from the images of the distribution of the radioactive material. A memory flagging system is then used to obtain quantitative information on a regional basis. Radio-cardiograms are performed following the intravenous injection of a bolus of 10 millicuries of {sup 99m}Tc, and rapid sequence recording of the cardiac inflow and outflow data is obtained at the rate of five frames per second. Upon completion of the study, the digital tape is played back and the locations of the four chambers of the heart are identified. The memory elements corresponding to each of these anatomical sites are then flagged, the data is replayed, and the inflow and outflow curves for each chamber are recorded separately. An EKG trigger device can be used to initiate every count-record cycle to permit the accumulation of data only during diastole. The resulting data is easier to interpret as changes in cardiac volume due to normal contractions are not recorded. This technique has been evaluated in 20 volunteers to establish normal values. Over 50 patients with congenital and acquired heart disease have been studied, and the following parameters evaluated: (1) cardiac output, (2) pulmonary blood transit time, (3) pulmonary blood volume, and (4) the quantitation of blood flow through abnormal shunts. (author)

Cardiovascular Topics The effect of anthracyclines on myocardial ...

African Journals Online (AJOL)

1999-02-01

Feb 1, 1999 ... Anthracyclines, which are effective in the treatment of childhood cancer, are known for their cardiotoxicity. In this study, with a mean follow-up of 116 months, the adverse effects of anthracyclines on conduction and myocardial function were evaluated by means of electro- cardiography and ...

A-V Delay Versus Cardiac Output Measured with Thorax Bioimpedance Monitor

Czech Academy of Sciences Publication Activity Database

Vondra, Vlastimil; Halámek, Josef; Viščor, Ivo; Jurák, Pavel; Novák, M.; Lipoldová, J.

2008-01-01

Roč. 6, č. 1 (2008), s. 73 ISSN 1556-7451. [World Congress on Heart Disease /14./. 26.07.2008-29.07.2008, Toronto] Institutional research plan: CEZ:AV0Z20650511 Keywords : atrio-ventricular delay * resynchronization therapy * impedance cardiography * cardiac output Subject RIV: FA - Cardiovascular Disease s incl. Cardiotharic Surgery

Design of Bioimpedance Monitor and Its Application to Atrioventricular Delay Optimization

Czech Academy of Sciences Publication Activity Database

Vondra, Vlastimil; Viščor, Ivo; Halámek, Josef; Jurák, Pavel

2009-01-01

Roč. 36, - (2009), s. 481-484 ISSN 0276-6574 R&D Projects: GA AV ČR IAA200650801; GA ČR GA102/08/1129 Institutional research plan: CEZ:AV0Z20650511 Keywords : bioimpedance monitor * impedance cardiography Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering http://cinc.mit.edu/archives/2009/pdf/0481.pdf

Cornelia-de Lange syndrome in an Egyptian infant with unusual ...

African Journals Online (AJOL)

Rabah M. Shawky

2012-05-18

May 18, 2012 ... in the right upper limb and both lower limbs dating since birth. There was no family history of a ... ECHO cardiography showed mild left pulmonary artery branch stenosis. .... MRI of the brain in our patient demonstrated brain atro- phy. ... the exact function of the protein product of NIPBL in humans. (delangin) ...

Review of Magneto cardiography Technology based on SQUID

Energy Technology Data Exchange (ETDEWEB)

Lee, Y. H.; Kwon, H.; Kim, J. M.; Kim, K.; Yu, K. K.; Park, Y. K. [Brain and Cognition Measurement Lab, Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

2012-04-15

Electric activity of cardiac muscles generates magnetic fields. Magnetocardiography (or MCG) technology, measuring these magnetic signals, can provide useful information for the diagnosis of heart diseases. It is already about 40 years ago that the first measurement of MCG signals was done by D. Cohen using SQUID (superconducting quantum interference device) sensor inside a magnetically shielded room. In the early period of MCG history, bulky point-contact RF-SQUID was used as the magnetic sensor. Thanks to the development of Nb-based Josephson junction technology in mid 1980s and new design of tightly-coupled DC-SQUID, low-noise SQUID sensors could be developed in late 1980s. In around 1990, several groups developed multi-channel MCG systems and started clinical study. However, it is quite recent years that the true usefulness of MCG was verified in clinical practice, for example, in the diagnosis of coronary artery disease. For the practical MCG system, technical elements of MCG system should be optimized in terms of performance, fabrication cost and operation cost. In this review, development history, technical issue, and future development direction of MCG technology are described.

Non-invasive cardiac imaging. Spectrum, methodology, indication and interpretation

International Nuclear Information System (INIS)

Schaefers, Michael; Flachskampf, Frank; Sechtem, Udo; Achenbach, Stephan; Krause, Bernd J.; Schwaiger, Markus; Breithardt, Guenter

2008-01-01

The book contains 13 contributions concerning the following chapters: (1)methodology: echo cardiography; NMR imaging; nuclear medicine; computer tomography, (2) clinical protocols: contraction; cardiac valve function; perfusion and perfusion reserve; vitality; corona imaging; transmitters, receptors, enzymes; (3) clinic: coronary heart diseases; non-ischemic heart diseases. The appendix contains two contributions on future developments and certification/standardization

A comparative study for the echo cardiographic, radiologic and electrocardiographic presentation of the sport heart hypertrophy

International Nuclear Information System (INIS)

Reinke, A.

1982-01-01

In this work the three most important non-invasive methods - X-ray pictures, electrocardiography and echo cardiography - were compared as to their ability to evaluate the physiological heart enlargement as a result of physical training. Important also was the study of the value of ultrasonic cardiographs. The subjects used were 162 athletes, 36 patients with cardiovascular diseases, and 22 non-athletic control persons. Radiologically the changes in the total size of the heart were determined. For the question of the adapting reaction of the heart because of athletic training the weight-related heart volume is more meaningful than the absolute value. Electrocardiographically it is not possible to come up with any statistically significant statements about the physiological heart enlargement using the Sokoloff-Lyon indexes. Echo cardiographically the regulative heart enlargements can be differentiated into myocardial hypertrophy or ventricular dilation. As a result of this a line can be drawn between physiological and pathological changes. Female athletes show qualitatively, but not quantitatively, the same adapting reaction. The synopsis of the three procedures shows that echo cardiography and radiology show better results than does electrocardiography. Together the methods complement each other in their diagnostic power. (orig./TRV) [de

Pulse and vital sign measurement in mixed reality using a HoloLens

OpenAIRE

Mcduff , Daniel; Hurter , Christophe; Gonzalez-Franco , Mar

2017-01-01

International audience; Cardiography, quantitative measurement of the functioning of the heart, traditionally requires customized obtrusive contact sensors. Using new methods photoplethysmography and ballistocardiography signals can be captured using ubiquitous sensors, such as webcams and accelerometers. However, these signals are not visible to the unaided eye. We present Cardiolens-a mixed reality system that enables real-time, hands-free measurement and visu-alization of blood ow and vita...

Central Hemodynamics Measured During 5 Repetition Maximum Free Weight Resistance Exercise.

Science.gov (United States)

Howard, Jonathan S; McLester, Cherilyn N; Evans, Thomas W; McLester, John R; Calloway, Jimmy P

2018-01-01

The PhysioFlow™ is a piece of equipment that uses bioimpedance cardiography to measure central hemodynamics. The purpose of this research was to explore the novel approach of monitoring central hemodynamics during free weight resistance exercise using bioimpedance cardiography throughout a 5 repetition maximum (5RM). Thirty participants ranging from beginner to advanced lifters (16 males and 14 females) completed a 5RM for back squat, seated push press, and bicep curl while connected to the PhysioFlow™ to assess the response of heart rate (HR), stroke volume (SV), cardiac output (Q), and ejection fraction (EF). Participants were cued for form and to breathe normally throughout the lifts. The PhysioFlow™ detected an increase in HR and Q for all lifts between rest and each repetition ( p 0.05) and no changes in EF or SV were detected when all repetitions were compared to each other for all lifts ( p > 0.05). In conclusion, the PhysioFlow™ was able to detect changes in HR and Q during dynamic free weight resistance exercise. This novel approach may provide a mechanism for monitoring central hemodynamics during free weight resistance training. However, more research needs to be conducted as the exercise protocol for this investigation did not allow for a comparison to a reference method.

N-terminal pro brain natriuretic peptide as a cardiac biomarker in Japanese hemodialysis patients.

Science.gov (United States)

Shimizu, Minako; Doi, Shigehiro; Nakashima, Ayumu; Naito, Takayuki; Masaki, Takao

2018-03-01

This study examined the clinical significance of N-terminal pro brain natriuretic peptide level as a cardiac marker in Japanese hemodialysis patients. This was a multicenter cross-sectional study involving 1428 Japanese hemodialysis patients. Ultrasonic cardiography data at post-hemodialysis were obtained from 395 patients. We examined whether serum N-terminal pro brain natriuretic peptide levels were associated with cardiac parameters and assessed cut-off values and investigated factors associated with a reduced ratio of N-terminal pro brain natriuretic peptide levels pre- and post-hemodialysis. Multivariate logistic regression analysis showed that pre- and post-hemodialysis N-terminal pro brain natriuretic peptide levels were associated with left ventricular hypertrophy on electrocardiogram (odds ratio: 3.10; p N-terminal pro brain natriuretic peptide levels were also significantly associated with ejection fraction on urine chorionic gonadotrophin (ultrasonic cardiography; odds ratio: 35.83; p N-terminal pro brain natriuretic peptide reduction ratio during a hemodialysis session correlated with Kt/V, membrane area, membrane type, modality, body weight gain ratio, treatment time, and ultrafiltration rate with multiple linear regression ( R: 0.53; p N-terminal pro brain natriuretic peptide are associated with the presence of left ventricular hypertrophy in this population. The post-hemodialysis N-terminal pro brain natriuretic peptide level is a useful marker for systolic dysfunction.

Estimation of global and regional ejection fraction of the left ventricle using a fully digitalised technique

International Nuclear Information System (INIS)

Tuengerthal, S.; Reifart, N.; Standke, R.; Lang, J.; Kollath, J.; Riemann, H.E.; Frankfurt Univ.; Frankfurt Univ.

1984-01-01

Subtraction angiocardiography (DSAK) with a fully digitalised system (DR 960) provides a well defined demonstration of the left ventricle after peripheral venous contrast injection. Cardiac volume and ejection fractions were calculated by a dedicated software programme and the findings correlated with cine ventriculography (CA) (r=0.91), biplane echo cardiography (2 DE) (r=0.77) and radionucleid ventriculography (RNV) (r=0.85); the method can be used even with reduced cardiac output (EF [de

Left ventricular mass in borderline hypertension assessed by echo cardiography

International Nuclear Information System (INIS)

Mezzasalma, L.; Ghione, S.; Palonebo, C.

1989-01-01

The relationship between clinical measurement of blood pressure (BP) and left ventricular hypertrophy in arterial hypertension appears to be weak in most studies. On the contrary, stronger correlations with target organ damage in general, and left ventricular hypertrophy in particular, have been reported for blood pressure measurements obtained by ambulatory monitoring; this finding may indicate a possible role for blood pressure response to naturally occurring stresses in determining left ventricular hypertrophy. Aim of this study was to investigate, in 18 patients with borderline arterial hypertension, the relationships between echocardiographically assessed left ventricular mass and, respectively, casual BP and BP responses to some standardized stress tests. Only three patients had a diastolic wall thickness of the interventricular septum and of the posterior wall ≥1.2 cm and none had a pathologically increased left ventricular mass index. The following statistically significant correlations were found: casual diastolic BP vs. left ventricular mass index (r=0.53, p<0.02), systolic BP response to bicycle exercise test vs. left ventricular mass index (r=0.55, p<0.05). Multiple regression analysis showed that almost fifty percent of the variability of left ventricular mass index could be predicted by these two BP measurements. These findings suggest that besides the chronically increased afterload, also the transient hypertensive responses to naturally occuring physical stresses may have a role in determining the extent of cardiac structural changes in borderline hypertensive patients. In addition, they indicate a direct relation between left ventricular mass and blood pressure levels also in borderline hypertension, as previously shown for established hypertension, despite the fact that left ventricular hypertrophy represents only an occasional finding in early stages of hypertension

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

Science.gov (United States)

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

2006-09-20

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

Effects of obstructive sleep apnea on hemodynamic parameters in patients entering cardiac rehabilitation.

Science.gov (United States)

Hargens, Trent A; Aron, Adrian; Newsome, Laura J; Austin, Joseph L; Shafer, Brooke M

2015-01-01

Obstructive sleep apnea (OSA) is a prevalent form of sleep-disordered breathing. Evidence suggests that OSA may lead to cardiac remodeling, although the literature is equivocal. Previous literature suggests a high percentage of individuals entering a cardiac rehabilitation (CR) program also have OSA. The objective of this study was to determine whether resting hemodynamic variables were altered in OSA subjects entering CR compared with those without OSA, as determined by impedance cardiography. Subjects entering an early outpatient CR program were screened for OSA using an at-home screening device and verified by a sleep physician. Subjects were divided into an OSA group (n = 48) or a control group (n = 25) on the basis of the screening results. Hemodynamic variables were measured during supine rest using impedance cardiography. A 6-minute walk test was performed to assess functional capacity. The proportion of cardiac diagnoses was similar between groups. Overall, 66% of the subjects were positive for OSA. Subject groups did not differ by age, body mass index, heart rate, diastolic blood pressure, or functional capacity. Cardiac output, cardiac index, stroke volume, contractility index, and left cardiac work index were all significantly decreased in the OSA group compared with the control group (P disadvantage in recovering from their cardiac event, and place them at increased risk for secondary complications.

Interpretation of plain film radiology in infants and children with cardiac and vascular malformations. Pt. 2

International Nuclear Information System (INIS)

Rautenburg, H.W.

1987-01-01

This second part shows that its interpreted correctly diagnostic plain film radiology may contribute important information to an often complicated differential diagnosis of complex angiocardiopthies exemplified here by various subforms and types of pulmonary and tricuspid atresias. Diagnostic plainfilm radiology, however, is just one part of total preliminary cardiological diagnostics. In many cases of congenital heart and vessel malformations, it is of great diagnostic value in the practical medical environment and does not compete with echo cardiography especially in easy diagnoses like that of lung perfusion. (orig.) [de

Hemodynamic function of the standard St. Jude bileaflet disc valve has no clinical impact 10 years after aortic valve replacement

DEFF Research Database (Denmark)

Lund, Ole; Dorup, Inge; Emmertsen, Kristian

2005-01-01

in the survivors of a prospective series 10 years after AVR for aortic stenosis. DESIGN: Forty-three survivors aged 32-90 years from a prospective series attended a follow-up study with Doppler echo and radionuclide cardiography 10 years after AVR for aortic stenosis. Six patients with significant left sided valve...... to St. Jude valve geometric orifice area (GOA) indexed for either body surface area or left ventricular end-diastolic dimension (LVEDD). The gradients correlated directly with LVEDD but not with LVEF or LVMi. Eleven patients with hypertension had higher peak gradients (31+/-13 versus 22+/-8 mmHg, p

Pulmonary valve insufficiency in the postoperative out of tetralogy of Fallot: contribution of conventional transthoracic echocardiography for decision making

International Nuclear Information System (INIS)

Guzzo de Leon, D.

2013-01-01

Pulmonary valve regurgitation is one of the main problems in the late post-op of Tetralogy of F allot, having a great incidence and depending on many aspects . In these paper a review is done considering the usefulness of conventional transtoracic eco cardiography as a tool to evaluate patients with pulmonary regurgitation in the late post-op of Tetralogy of F allot. Main pathophysiologic concepts about these entity are presented, and as a function of that, the most important eco cardiographic parameters to be considered evaluating these patients are also described. Finally guidelines on the opportunity for pulmonary valve replacement are considered

Variable impedance cardiography waveforms: how to evaluate the preejection period more accurately

International Nuclear Information System (INIS)

Ermishkin, V V; Kolesnikov, V A; Lukoshkova, E V; Mokh, V P; Sonina, R S; Dupik, N V; Boitsov, S A

2012-01-01

Impedance method has been successfully applied for left ventricular function assessment during functional tests. The preejection period (PEP), the interval between Q peak in ECG and a specific mark on impedance cardiogram (ICG) which corresponds to aortic valve opening, is an important indicator of the contractility state and its neurogenic control. Accurate identification of ejection onset by ICG is often problematic, especially in the cardiologic patients, due to peculiar waveforms. An essential obstacle is variability of the shape of the ICG waveform during the exercise and subsequent recovery. A promissing solution can be introduction of an additional pulse sensor placed in the nearby region. We tested this idea in 28 healthy subjects and 6 cardiologic patients using a dual-channel impedance cardiograph for simultaneous recording from the aortic and neck regions, and an earlobe photoplethysmograph. Our findings suggest that incidence of abnormal complicated ICG waveforms increases with age. The combination of standard ICG with ear photoplethysmography and/or additional impedance channel significantly improves the efficacy and accuracy of PEP estimation.

Haemodynamic changes following treatment of subclinical and overt hyperthyroidism

DEFF Research Database (Denmark)

Faber, J; Wiinberg, N; Schifter, S

2001-01-01

Hyperthyroidism has profound effects on the cardiovascular system, including reduced systemic vascular resistance (SVR) due to relaxation of vascular smooth muscle cells, enhanced heart rate (HR) and cardiac output (CO) due to an increase in cardiac diastolic relaxation, contractility and heart...... rate. Subclinical hyperthyroidism is characterised by reduced serum TSH levels despite free thyroxine (T4) and tri-iodothyronine (T3) estimates within the reference range, in subjects with no obvious symptoms of hyperthyroidism. We measured haemodynamic changes (using impedance cardiography......) in subjects with endogenous subclinical hyperthyroidism in order to elucidate whether these patients had signs of excess thyroid hormone at the tissue level....

Assessing cardiac preload by the Initial Systolic Time Interval obtained from impedance cardiography

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Jan H Meijer

2010-01-01

Full Text Available The Initial Systolic Time Interval (ISTI, obtained from the electrocardiogram (ECG and impedance cardiogram (ICG, is considered to be a measure for the time delay between the electrical and mechanical activity of the heart and reflects an early active period of the cardiac cycle. The clinical relevance of this time interval is subject of study. This paper presents preliminary results of a pilot study investigating the use of ISTI in evaluating and predicting the circulatory response to fluid administration in patients after coronary artery bypass graft surgery, by comparing ISTI with cardiac output (CO responsiveness. Also the use of the pulse transit time (PTT, earlier recommended for this purpose, is investigated. The results show an inverse relationship between ISTI and CO at all moments of fluid administration and also an inverse relationship between the changes ΔISTI and ΔCO before and after full fluid administration. No relationships between PTT and CO or ΔPTT and ΔCO were found. It is concluded that ISTI is dependent upon preload, and that ISTI has the potential to be used as a clinical parameter assessing preload.

The inflammatory biomarker YKL-40 as a new prognostic marker for all-cause mortality in patients with heart failure

DEFF Research Database (Denmark)

Harutyunyan, Marina; Christiansen, Michael; Johansen, Julia S

2011-01-01

peptide (NT-proBNP) could be a new prognostic biomarker for all-cause mortality in patients with HF. METHODS AND RESULTS: A total of 717 of the 1000 patients with severe left ventricular systolic dysfunction included in the EchoCardiography and Heart Outcome Study were included in Denmark and had blood...... YKL-40 II to IV quartiles, respectively following multivariable adjustment for cardiovascular risk factors (age, left ventricular ejection fraction, gender, history of heart failure, ischemic heart disease, chronic pulmonary disease, diabetes mellitus, stroke, hypertension, NT-proBNP, hs......-CRP, and renal function). CONCLUSION: Serum YKL-40 is significantly associated with all-cause mortality in patients with HF and could potentially be a new prognostic biomarker in these patients....

Evaluación hemodinámica no invasiva con cardiografía de impedancia: aplicaciones en falla cardíaca y en hipertensión arterial Non-invasive hemodynamic evaluation with impedance cardiography: applications in heart failure and hypertension

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Jon Kepa Balparda

2012-04-01

Full Text Available La cardiografía de impendancia (CGI representa un método no invasivo para la evaluación del estado hemodinámico latido a latido. Aunque se introdujo por primera vez hace más de 40 años, la CGI ha mostrado un resurgimiento en la última década, a partir de una serie de estudios clínicos que han demostrado su precisión en la estimación del volumen latido, tanto contra el "gold-standard" invasivo (termodilución, como contra los métodos de referencia no invasivos (ecocardiografía. Diversos estudios demuestran la utilidad de esta técnica en el manejo del paciente con falla cardíaca y en el enfoque diagnóstico y terapéutico de la hipertensión arterial, por lo cual constituyen actualmente dos de las aplicaciones clínicas más importantes de la CGI. En falla cardiaca, los cambios en el volumen de líquido del tórax y del gasto cardíaco evaluados por CGI, han demostrado ser predictores de descompensación aguda, incluso semanas antes del inicio de la sintomatología respiratoria; además, permiten identificar el origen cardiogénico o respiratorio de la disnea cuando el examen físico y los demás paraclínicos no son concluyentes. En los pacientes con hipertensión arterial no controlada o resistente, la CGI permite realizar una mejor caracterización del fenotipo hipertensivo y elegir la estrategia farmacológica más específica para intervenir la alteración hemodinámica predominante (resistencia vascular vs. gasto cardiaco elevado. En este artículo se realiza una revisión de los principios biofísicos de la CGI y su utilidad en la evaluación no invasiva del estado hemodinámico, así como una evaluación crítica de la literatura que da soporte a su aplicación clínica en el tratamiento de la falla cardíaca y la hipertensión arterial.Impedance cardiography (ICG represents a non-invasive method for hemodynamic assessment in a beat-to-beat basis. Since its introduction more than forty years ago, a renewed interest in the

Methods and systems for the processing of physiological signals

International Nuclear Information System (INIS)

Cosnac, B. de; Gariod, R.; Max, J.; Monge, V.

1975-01-01

This note is a general survey of the processing of physiological signals. After an introduction about electrodes and their limitations, the physiological nature of the main signals are shortly recalled. Different methods (signal averaging, spectral analysis, shape morphological analysis) are described as applications to the fields of magnetocardiography, electro-encephalography, cardiography, electronystagmography. As for processing means (single portable instruments and programmable), they are described through the example of application to rheography and to the Plurimat'S general system. As a conclusion the methods of signal processing are dominated by the morphological analysis of curves and by the necessity of a more important introduction of the statistical classification. As for the instruments, microprocessors will appear but specific operators linked to computer will certainly grow [fr

Comparing impedance cardiography and echocardiography in the assessment of reduced left ventricular systolic function

DEFF Research Database (Denmark)

Kaszuba, Elzbieta; Scheel, Sergej; Odeberg, Håkan

2013-01-01

An early and accurate diagnosis of chronic heart failure is a big challenge for a general practitioner. Assessment of left ventricular function is essential for the diagnosis of heart failure and the prognosis. A gold standard for identifying left ventricular function is echocardiography...

Berardinelli–Seip syndrome type 2 – An Egyptian child

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Rabah M. Shawky

2015-04-01

Full Text Available We report a 2.5 year old male, first in order of birth of first cousin consanguineous parents with the typical features of Berardinelli–Seip congenital lipodystrophy 2 (BSCL2 since birth with moderate mental retardation. He had generalized lipodystrophy with various dermatologic and systemic manifestations. The patient looked older than his age with the loss of buccal pad of fat, hypertrichosis mainly on the back and lower limbs, thick scalp hair, mild prognathism, large hands and feet with prominent joints and muscular hypertrophy. Acanthosis nigricans was evident over the neck and both axillae inspite of the normal level of sugar and insulin. The abdomen was markedly prominent with mild hepatosplenomegaly and enlarged external genitals. Echo-cardiography demonstrated cardiac hypertrophy. Triglyceride level was high with reduced high density lipoproteins (HDL.

Haemodynamic effects of eating

DEFF Research Database (Denmark)

Høost, U; Kelbaek, H; Rasmusen, H

1996-01-01

to obtain forearm blood flow and Doppler-ultrasonography for portal vein flow. Plasma levels of catecholamines and insulin were determined by radioimmunoassay. 3. Cardiac output increased considerably after each meal, including the control meal (water) with only minor differences in extent and timing. Left......1. The purpose of this study was to investigate the effect of fractional meal stimulation on postprandial haemodynamic changes, the possible correlation between these changes and the potential mediating role of circulating catecholamines and insulin. 2. Healthy young subjects were studied before...... and after ingestion of isocaloric, isovolumetric high-protein, carbohydrate or fat meals (80-85% of total energy), 60 kJ per kg of body weight. Multigated radionuclide cardiography with autologous 99mTc-labelled erythrocytes was performed for assessment of cardiac output, venous occlusion plethysmography...

Non-invasive measurements of cardiac output in atrial fibrillation: Inert gas rebreathing and impedance cardiography

DEFF Research Database (Denmark)

Osbak, Philip S; Henriksen, Jens Henrik Sahl; Kofoed, Klaus F

2011-01-01

Abstract Background. Atrial fibrillation (AF) is associated with significant morbidity and mortality. To test the effect of interventions, knowledge of cardiac output (CO) is important. However, the irregular heart rate might cause some methods for determination of CO to have inherent weaknesses....

Method to measure autonomic control of cardiac function using time interval parameters from impedance cardiography

International Nuclear Information System (INIS)

Meijer, Jan H; Boesveldt, Sanne; Elbertse, Eskeline; Berendse, H W

2008-01-01

The time difference between the electrocardiogram and impedance cardiogram can be considered as a measure for the time delay between the electrical and mechanical activities of the heart. This time interval, characterized by the pre-ejection period (PEP), is related to the sympathetic autonomous nervous control of cardiac activity. PEP, however, is difficult to measure in practice. Therefore, a novel parameter, the initial systolic time interval (ISTI), is introduced to provide a more practical measure. The use of ISTI instead of PEP was evaluated in three groups: young healthy subjects, patients with Parkinson's disease, and a group of elderly, healthy subjects of comparable age. PEP and ISTI were studied under two conditions: at rest and after an exercise stimulus. Under both conditions, PEP and ISTI behaved largely similarly in the three groups and were significantly correlated. It is concluded that ISTI can be used as a substitute for PEP and, therefore, to evaluate autonomic neuropathy both in clinical and extramural settings. Measurement of ISTI can also be used to non-invasively monitor the electromechanical cardiac time interval, and the associated autonomic activity, under physiological circumstances

Person perception and autonomic nervous system response: the costs and benefits of possessing a high social status.

Science.gov (United States)

Cloutier, J; Norman, G J; Li, T; Berntson, G G

2013-02-01

This research was designed to investigate the relationship between sympathetic and parasympathetic autonomic nervous system (ANS) responses to the perception of social targets varying in social status. Participants varying in subjective financial status were presented with faces assigned with either a low, average, or high financial status. Electrocardiographic and impedance cardiography signals were recorded and measures of sympathetic (pre-ejection period; PEP) and parasympathetic (high frequency heart rate variability; HF HRV) cardiac control were derived. These measures associated with the presentation of each face condition were examined in relation to the subjective status of the perceivers. Participants with high subjective financial status showed reduced sympathetic activity when viewing low- and medium-status targets as compared to high-status targets, and lower parasympathetic response when viewing high- and medium-status targets relative to low-status targets. Copyright © 2012. Published by Elsevier B.V.

Non-Contact Monitoring of Heart and Lung Activity by Magnetic Induction Measurement

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M. Steffen

2008-01-01

Full Text Available In many clinical applications, the monitoring of heart and lung activity is of vital importance. State-of-the-art monitoring involves the use of electrodes or other contact based sensors (electrocardiogram (ECG, impedance cardiography (ICG, pulse oximetry or equivalent. With the equipment that is used, side effects like skin irritation, difficult application or additional cabling may occur. In contrast, this paper describes a method for non-contact monitoring of heart and lung activity, which is solely based on magnetic induction. This method allows simultaneous monitoring of heart and lung activity, and has the potential of an integrated application in a personal healthcare scenario. To illustrate the performance, a simple test-setup has been developed and the first results are presented here (some of which have been previously presented on the Poster 2008 [10]. 

Can M mode and two dimensional echocardiography give a sufficient evaluation for surgeray of patients with pure mitral stenosis

International Nuclear Information System (INIS)

Balbarini, A; Tartarini, G.; Mengozzi, G.; Mariani, M.; Salvatore, L.; Barsotti, A.

1987-01-01

One hundred and twenty-six patients with rheumatic mitral stenosis were studied by M-mode and/or two-dimensional echocardiography. Eighty-nine patients were also submetted to cardiac catheterization and all 126 patients subsequently underwent mitral valve surgery (51 valvulotomy and 75 valve replacement). The mitral valve area measured by two-dimensional echocardiography showed a significant correlation both with hemodynamic (r=0.803, p 2 , respectively; likewise there was non significant difference in pulmonary vascular resistances (3.9 and 3.4 mmHg/l/min/m 2 ) between patients who showed functional improvement after surgery comparison to those who showed no improvement. Finally, coronary arteriography appeared to be necessary, before operation, only in cardiography is able to provide a satisfactory preoperative assessment of patients with mitral stenosis and that therefore these patients need not necessarily to be submitted to cardiac catheterization

Clinical usefullness of ECG-triggered single photon emission comuter tomography of blood-pool

International Nuclear Information System (INIS)

Eilles, Chr.; Boerner, W.; Strauss, P.; Gerhards, W.; Reiners, Ch.

1982-01-01

ECT allows direct measurement of the volume of an organ and imaging without disturbing background-superposition. This makes ECT to an useful instrument for ECG-gated blood-pool imaging. Acquisition is made after the injection of 25 mCi Tc-99m HSA with a rotating Anger-Camera-System. ECG-gated imaging is done for each projection; herewith 50-70 cycles per projection are added according to the phase of the heart-cycle. Transversal-Sections of the heart are reconstructed with filtered-back-projection. For each slice a representative cycle, consisting of 10-16 frames, is computed. As shown by our group before a good quality of the reconstructed images can be obtained. Comparison is made with the results of the ECG-gated blood-pool-ECT, the results of the conventional blood-pool-studies and with the results of Laevo-Cardiography. (Author)

Cardiac output during exercise

DEFF Research Database (Denmark)

Siebenmann, C; Rasmussen, P.; Sørensen, H.

2015-01-01

Several techniques assessing cardiac output (Q) during exercise are available. The extent to which the measurements obtained from each respective technique compares to one another, however, is unclear. We quantified Q simultaneously using four methods: the Fick method with blood obtained from...... the right atrium (Q(Fick-M)), Innocor (inert gas rebreathing; Q(Inn)), Physioflow (impedance cardiography; Q(Phys)), and Nexfin (pulse contour analysis; Q(Pulse)) in 12 male subjects during incremental cycling exercise to exhaustion in normoxia and hypoxia (FiO2  = 12%). While all four methods reported...... a progressive increase in Q with exercise intensity, the slopes of the Q/oxygen uptake (VO2) relationship differed by up to 50% between methods in both normoxia [4.9 ± 0.3, 3.9 ± 0.2, 6.0 ± 0.4, 4.8 ± 0.2 L/min per L/min (mean ± SE) for Q(Fick-M), Q(Inn), QP hys and Q(Pulse), respectively; P = 0...

Development of improved superconductive axial gradiometers for biomagnetic SQUID applications

Science.gov (United States)

Budnyk, M. M.; Minov, Yu. D.; Lyakhno, V. Yu.; Desnenko, V. A.; Linnik, A. S.; Shopen, O. B.

2018-03-01

SQUID magnetometers for biomagnetic measurements are equipped with superconductive gradiometers which are required to provide a high signal-to-noise ratio at low frequencies, sufficient mechanical strength and sustained performance under repeated thermal cycles, as well as a low level of intrinsic magnetic noise. This paper describes the design of a gradiometer made with a carbon-fiber reinforced composite material for magnetic cardiography measurements. The thermal coefficient of linear expansion (TCLE) of the carbon fiber composite can be precisely adjusted to match that of the superconducting detector coil wire. This is achieved thanks to the difference in the TCLE of carbon fibers in the longitudinal and transverse directions and is realized by varying the laying directions of the fiber in the composite. The data of magnetic susceptibility measurements on carbon fiber composite are reported, showing the magnetic susceptibility about six times smaller than that of graphite. The presented gradiometer design provides a high degree of balancing and is patented along side other specific techniques.

A new 99mTc-red blood cell labeling procedure for cardiac blood pool imaging: Clinical results

International Nuclear Information System (INIS)

Kelbaek, H.; Buelow, K.; Aldershvile, J.; Moegelyang, J.; Nielsen, S.L.; Copenhagen Univ.

1989-01-01

The first clinical results of a new 99m Tc-red blood cell labeling procedure avoiding cell centrifugation are presented. One ml heparinized blood samples were incubated with small amounts of a stannous kit. By titration studies, ideal quantities of sodium hypochlorite for oxidation of extracellular tin and of EDTA as stabilizer of the label were found. The Cl - concentration and pH of the labeled blood were acceptable, and EDTA increased labeling yield and stability determined in vitro by a few percent. The new procedure gave a slightly higher labeling yield than a current technique using centrifugation of cells. Labeling efficiency expressed as cell bound/total activity was 96.6%±1.3% in healthy subjects and 95.5%±2.2% in cardiac patients and remained high for 2 h after reinjection. The biological halflife of labeled cells following the new procedure was 11-12 h rendering it suitable for serial determinations of radionuclide cardiography. (orig.)

Peripheral Circulatory Features during High-Frequency Jet Ventilation

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M. B. Kontorovich

2010-01-01

Full Text Available The paper gives the results of a study of peripheral circulatory features during high-frequency jet ventilation (HFJV. The main specific features of peripheral circulation and oxygen transport during HFJV are formulated on the basis of a study of cardiac output (impedance cardiography, peripheral vascular resistance, peripheral vascular blood filling (photoplethysmogram analysis, adaptive peripheral blood flow reactions (spectral analysis of peripheral vascular pulsation. HFJV gives rise to the peculiar pattern of peripheral hemodynamics and tissue gas exchange, which is characterized by higher oxygen uptake without a decrease in mixed venous blood saturation, with normal extraction coefficient and preserved low peripheral vascular resistance. During HFJV, unlike traditional ventilation, the main peripheral hemodynamic feature is the increased capillary bed blood volume caused by the blood flow involvement of reserve capillaries under control of volume (parasympathetic regulation of adaptive peripheral hemodynamic reactions. Key words: high-frequency jet ventilation, oxygen transport, peripheral hemodynamics.

Gritty people try harder: grit and effort-related cardiac autonomic activity during an active coping challenge.

Science.gov (United States)

Silvia, Paul J; Eddington, Kari M; Beaty, Roger E; Nusbaum, Emily C; Kwapil, Thomas R

2013-05-01

Grit, a recently proposed personality trait associated with persistence for long-range goals, predicts achievement in a wide range of important life outcomes. Using motivational intensity theory, the present research examined the physiological underpinnings of grit during an active coping task. Forty young adults completed the Short Grit Scale and worked on a self-paced mental effort task. Effort-related autonomic nervous system (ANS) activity was assessed using impedance cardiography, which yielded measures of sympathetic activity (pre-ejection period; PEP) and parasympathetic activity (respiratory sinus arrhythmia; RSA). Multilevel models revealed that people high on the Perseverance of Effort subscale showed autonomic coactivation: both PEP and RSA became stronger during the task, reflecting higher activity of both ANS divisions. The Consistency of Interest subscale, in contrast, predicted only weaker sympathetic activity (slower PEP). Taken together, the findings illuminate autonomic processes associated with how "gritty" people pursue goals, and they suggest that more attention should be paid to the facets' distinct effects. Copyright © 2013 Elsevier B.V. All rights reserved.

The Higher the Insulin Resistance the Lower the Cardiac Output in Men with Type 1 Diabetes During the Maximal Exercise Test.

Science.gov (United States)

Niedzwiecki, Pawel; Naskret, Dariusz; Pilacinski, Stanislaw; Pempera, Maciej; Uruska, Aleksandra; Adamska, Anna; Zozulinska-Ziolkiewicz, Dorota

2017-06-01

The aim of this study was to assess the hemodynamic parameters analyzed in bioimpedance cardiography during maximal exercise in patients with type 1 diabetes differing in insulin resistance. The study group consisted of 40 men with type 1 diabetes. Tissue sensitivity to insulin was assessed on the basis of the glucose disposal rate (GDR) analyzed during hyperinsulinemic-euglycemic clamp. Patients were divided into groups with GDR insulin sensitivity) and GDR ≥4.5 mg/kg/min (G2 group-higher insulin sensitivity). During the exercise test, the heart rate, systolic volume, cardiac output, cardiac index were measured by the impedance meter (PhysioFlow). Compared with the G2 group, the G1 group had a lower cardiac output (CO): during exercise 8.6 (IQR 7.7-10.0) versus 12.8 (IQR 10.8-13.7) L/min; P insulin resistance is associated with cardiac hemodynamic parameters assessed during and after exercise. The higher the insulin resistance the lower the cardiac output during maximal exercise in men with type 1 diabetes.

Pattern of left ventricular hypertrophy seen on transthoracic echo in patients with hypertensive cardiomyopathy when compared with idiopathic hypertrophic cardiomyopathy

International Nuclear Information System (INIS)

Mirza, S. J.; Radaideh, G. A.

2013-01-01

Objective: To explore the pattern of left ventricular hypertrophy caused by hypertension and to compare it with idiopathic hypertrophic cardiomyopathy. Methods: The retrospective study was conducted at the echocardiography lab of Rashid Hospital, Dubai, from January 2009 to January 2010. Cases of 11 patients with significant left ventricular hypertrophy (septum >15mm) due to underlying hypertension were analysed and compared with 11 cases of idiopathic hypertrophic cardiography (septum >15mm) to assess the two groups with similar baseline echocardiographic features. Minitab software was used for statistical analysis. Results: Although the pattern of hypertrophy in hypertensive patients was more concentric (n=5; 45%), there was also asymmetrical septal hypertrophy in 4 (36%) cases, particularly the elderly with sigmoid shape septum. There was evidence of resting mid-cavity gradient due to reduced left ventricular end-systolic diameter in 4 (36%) cases. Conclusion: Although the equation between hypertension and left ventricular hypertrophy is more concentric, but it can be associated with left ventricular outflow tract obstruction and significant mid-cavity gradients similar to that seen in idiopathic hypertrophic cardiomyopathy. (author)

Cardiac chamber scintiscanning

International Nuclear Information System (INIS)

Goretzki, G.

1981-01-01

The two methods of cardiac chamber scintiscanning, i.e. 'first pass' and 'ECG-triggered' examinations, are explained and compared. Two tables indicate the most significant radiation doses of the applied radio tracers, i.e. 99m-Tc-pertechnetate and 99m-Tc-HSA, to which a patient is exposed. These averaged values are calculated from various data given in specialised literature. On the basis of data given in literature, an effective half-life of approximately 5 hours in the intravascular space was calculated for the erythrocytes labelled with technetium 99m. On this basis, the radiation doses for the patients due to 99m-Tc-labelled erythrocytes are estimated. The advantages and disadvantages of the two methods applied for cardiac chamber scintiscanning are put into contrast and compared with the advantages and disadvantages of the quantitative X-ray cardiography of the left heart. The still existing problems connected with the assessment of ECG-triggered images are discussed in detail. The author performed investigations of his own, which concerned the above-mentioned problems. (orig./MG) [de

Influence of physiological sources on the impedance cardiogram analyzed using 4D FEM simulations

International Nuclear Information System (INIS)

Ulbrich, Mark; Leonhardt, Steffen; Walter, Marian; Mühlsteff, Jens

2014-01-01

Impedance cardiography is a simple and inexpensive method to acquire data on hemodynamic parameters. This study analyzes the influence of four dynamic physiological sources (aortic expansion, heart contraction, lung perfusion and erythrocyte orientation) on the impedance signal using a model of the human thorax with a high temporal resolution (125 Hz) based on human MRI data. Simulations of electromagnetic fields were conducted using the finite element method. The ICG signal caused by these sources shows very good agreement with the measured signals (r = 0.89). Standard algorithms can be used to extract characteristic points to calculate left ventricular ejection time and stroke volume (SV). In the presented model, the calculated SV equals the implemented left ventricular volume change of the heart. It is shown that impedance changes due to lung perfusion and heart contraction compensate themselves, and that erythrocyte orientation together with the aortic impedance basically form the ICG signal while taking its characteristic morphology from the aortic signal. The model is robust to conductivity changes of tissues and organ displacements. In addition, it reflects the multi-frequency behavior of the thoracic impedance. (paper)

The prognostic importance of lung function in patients admitted with heart failure.

Science.gov (United States)

Iversen, Kasper Karmark; Kjaergaard, Jesper; Akkan, Dilek; Kober, Lars; Torp-Pedersen, Christian; Hassager, Christian; Vestbo, Jorgen; Kjoller, Erik

2010-07-01

The purpose of the present study was to determine the prognostic importance for all-cause mortality of lung function variables obtained by spirometry in an unselected group of patients admitted with heart failure (HF). This was a prospective prognostic study performed as part of the EchoCardiography and Heart Outcome Study (ECHOS). This analysis included 532 patients admitted with a clinical diagnosis of HF. All patients underwent spirometry and echocardiography and the diagnosis of HF was made according to established criteria. Mean forced expiratory volume in 1 s (FEV(1)) was 65% of the predicted value [95% confidence interval (CI) 63-67%], mean forced vital capacity (FVC) was 71% of predicted (95% CI 69-72%), and FEV(1)/FVC was 0.72 (95% CI 0.71-0.73). FEV(1), FVC, and FEV(1)/FVC were all significant prognostic factors for all-cause mortality in univariate analyses. In a multivariate analysis, FEV(1) had independent prognostic value (hazard ratio 0.86 per 10% change, P information for all-cause mortality in patients admitted with HF. Spirometry therefore seems to be worth considering for all patients admitted with HF in order to identify patients at high risk.

Online Epileptic Seizure Prediction Using Wavelet-Based Bi-Phase Correlation of Electrical Signals Tomography.

Science.gov (United States)

Vahabi, Zahra; Amirfattahi, Rasoul; Shayegh, Farzaneh; Ghassemi, Fahimeh

2015-09-01

Considerable efforts have been made in order to predict seizures. Among these methods, the ones that quantify synchronization between brain areas, are the most important methods. However, to date, a practically acceptable result has not been reported. In this paper, we use a synchronization measurement method that is derived according to the ability of bi-spectrum in determining the nonlinear properties of a system. In this method, first, temporal variation of the bi-spectrum of different channels of electro cardiography (ECoG) signals are obtained via an extended wavelet-based time-frequency analysis method; then, to compare different channels, the bi-phase correlation measure is introduced. Since, in this way, the temporal variation of the amount of nonlinear coupling between brain regions, which have not been considered yet, are taken into account, results are more reliable than the conventional phase-synchronization measures. It is shown that, for 21 patients of FSPEEG database, bi-phase correlation can discriminate the pre-ictal and ictal states, with very low false positive rates (FPRs) (average: 0.078/h) and high sensitivity (100%). However, the proposed seizure predictor still cannot significantly overcome the random predictor for all patients.

Simulation of 'pathologic' changes in ICG waveforms resulting from superposition of the 'preejection' and ejection waves induced by left ventricular contraction

Science.gov (United States)

Ermishkin, V. V.; Kolesnikov, V. A.; Lukoshkova, E. V.; Sonina, R. S.

2013-04-01

The impedance cardiography (ICG) is widely used for beat-to-beat noninvasive evaluation of the left ventricular stroke volume and contractility. It implies the correct determination of the ejection start and end points and the amplitudes of certain peaks in the differentiated impedance cardiogram. An accurate identification of ejection onset by ICG is often problematic, especially in the cardiologic patients, due to peculiar waveforms. Using a simple theoretical model, we tested the hypothesis that two major processes are responsible for the formation of impedance systolic wave: (1) the changes in the heart geometry and surrounding vessels produced by ventricular contraction, which occur during the isovolumic phase and precede ejection, and (2) expansion of aorta and adjacent arteries during the ejection phase. The former process initiates the preejection wave WpE and the latter triggers the ejection wave WEj. The model predicts a potential mechanism of generating the abnormal shapes of dZ/dt due to the presence of preejection waves and explains the related errors in ICG time and amplitude parameters. An appropriate decomposition method is a promising way to avoid the masking effects of these waves and a further step to correct determination of the onset of ejection and the corresponding peak amplitudes from 'pathologically shaped' ICG signals.

PREDICTIVE FACTORS FOR THE PROGRESSION OF CHRONIC CHAGAS CARDIOMYOPATHY IN PATIENTS WITHOUT LEFT VENTRICULAR DYSFUNCTION

Directory of Open Access Journals (Sweden)

Silvana de Araújo SILVA

2015-04-01

Full Text Available The identification of predictors for the progression of chronic Chagas cardiomyopathy (CCC is essential to ensure adequate patient management. This study looked into a non-concurrent cohort of 165 CCC patients between 1985 and 2010 for independent predictors for CCC progression. The outcomes were worsening of the CCC scores and the onset of left ventricular dysfunction assessed by means of echo-Doppler cardiography. Patients were analyzed for social, demographic, epidemiologic, clinical and workup-related variables. A descriptive analysis was conducted, followed by survival curves based on univariate (Kaplan-Meier and Cox’s univariate model and multivariate (Cox regression model analysis. Patients were followed from two to 20 years (mean: 8.2. Their mean age was 44.8 years (20-77. Comparing both iterations of the study, in the second there was a statistically significant increase in the PR interval and in the QRS duration, despite a reduction in heart rates (Wilcoxon < 0.01. The predictors for CCC progression in the final regression model were male gender (HR = 2.81, Holter monitoring showing pauses equal to or greater than two seconds (HR = 3.02 increased cardiothoracic ratio (HR = 7.87 and time of use of digitalis (HR = 1.41. Patients with multiple predictive factors require stricter follow-up and treatment.

Genomic ancestry as a predictor of haemodynamic profile in heart failure.

Science.gov (United States)

Bernardez-Pereira, Sabrina; Gioli-Pereira, Luciana; Marcondes-Braga, Fabiana G; Santos, Paulo Caleb Junior Lima; Spina, Joceli Mabel Rocha; Horimoto, Andréa Roseli Vançan Russo; Santos, Hadassa Campos; Bacal, Fernando; Fernandes, Fábio; Mansur, Alfredo Jose; Pietrobon, Ricardo; Krieger, José Eduardo; Mesquita, Evandro Tinoco; Pereira, Alexandre Costa

2016-01-01

The aim of this study is to assess the association between genetic ancestry, self-declared race and haemodynamic parameters in patients with chronic heart failure (HF). Observational, cross-sectional study. Eligible participants were aged between 18 and 80 years; ejection fraction was ≤50%. Patients underwent genetic analysis of ancestry informative markers, echocardiography and impedance cardiography (ICG). Race was determined by self-classification into two groups: white and non-white. Genomic ancestry was estimated using a panel of 101 348 polymorphic markers and three continental reference populations (European, African and Native American). Our study included 362 patients with HF between August 2012 and August 2014. 123 patients with HF declared themselves as white and 234 patients declared themselves as non-white. No statistically significant differences were found regarding the ICG parameters according to self-declared race. The Amerindian ancestry was positively correlated with systolic time ratio (r=0.109, pancestry. In multiple linear regression, African ancestry remained associated with the E/e' ratio, even after adjustment to risk factors. The African genetic ancestry was associated with worse parameters of diastolic function; the Amerindian ancestry correlated with a worse pattern of ventricular contractility, while self-declared colour was not helpful to infer haemodynamic profiles in HF. NTC02043431.

Chinese Medicine Shenfu Injection for Heart Failure: A Systematic Review and Meta-Analysis

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Song Wen-Ting

2012-01-01

Full Text Available Objective. Heart failure (HF is a global public health problem. Early literature studies manifested that Shenfu injection (SFI is one of the most commonly used traditional Chinese patent medicine for HF in China. This article intended to systematically evaluate the efficacy and safety of SFI for HF. Methods. An extensive search was performed within 6 English and Chinese electronic database up to November 2011. Ninety-nine randomized controlled trails (RCTs were collected, irrespective of languages. Two authors extracted data and assessed the trial quality independently. RevMan 5.0.2 was used for data analysis. Results. Compared with routine treatment and/or device support, SFI combined with routine treatment and/or device support showed better effect on clinical effect rate, mortality, heart rate, NT-proBNP and 6-minute walk distance. Results in ultrasonic cardiography also showed that SFI combined with routine treatment improved heart function of HF patients. There were no significant difference in blood pressure between SFI and routine treatment groups. Adverse events were reported in thirteen trails with thirteen specific symptoms, while no serious adverse effect was reported. Conclusion. SFI appear to be effective for treating HF. However, further rigorously designed RCTs are warranted because of insufficient methodological rigor in the majority of included trials.

Chinese medicine shenfu injection for heart failure: a systematic review and meta-analysis.

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Wen-Ting, Song; Fa-Feng, Cheng; Li, Xu; Cheng-Ren, Lin; Jian-Xun, Liu

2012-01-01

Objective. Heart failure (HF) is a global public health problem. Early literature studies manifested that Shenfu injection (SFI) is one of the most commonly used traditional Chinese patent medicine for HF in China. This article intended to systematically evaluate the efficacy and safety of SFI for HF. Methods. An extensive search was performed within 6 English and Chinese electronic database up to November 2011. Ninety-nine randomized controlled trails (RCTs) were collected, irrespective of languages. Two authors extracted data and assessed the trial quality independently. RevMan 5.0.2 was used for data analysis. Results. Compared with routine treatment and/or device support, SFI combined with routine treatment and/or device support showed better effect on clinical effect rate, mortality, heart rate, NT-proBNP and 6-minute walk distance. Results in ultrasonic cardiography also showed that SFI combined with routine treatment improved heart function of HF patients. There were no significant difference in blood pressure between SFI and routine treatment groups. Adverse events were reported in thirteen trails with thirteen specific symptoms, while no serious adverse effect was reported. Conclusion. SFI appear to be effective for treating HF. However, further rigorously designed RCTs are warranted because of insufficient methodological rigor in the majority of included trials.

Polymorphism Glu389Arg of β1-adrenoreceptor gene and cardiovascular complications of hyperthyroidism

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A Yu Babenko

2010-06-01

Full Text Available Gly389Arg polymorphism β1-adrenoreceptors can influence the cardio-vascular prognosis. Human heart β1-adrenoreceptors perform a crucial role in mediating the cardiostimulant effects of norepinephrine. Understanding the significance of Gly389Arg polymorphism in the human heart is beginning to emerge, but not in adult patients with thyrotoxicosis. We've studied the Gly389Arg polymorphism of β1-adrenoreceptors gene in relation to Echo-cardiography parameters in 136 normotensive patients with a thyrotoxicosis without any CVD. Echo-CG was performed according to standard protocol before and during the thyreostatic treatment. The genotype distribution was as following: Gly/Gly – 25% (1 group (1 gr., Arg/Gly – 75% (2 group (2 gr., Arg/Arg – 0%. There was significant difference between 1 and 2 gr. by relative left ventricle wall thickness, left ventricular mass index, isovolumic relaxation time, Е/А ratio. The frequency of diastolic dysfunction (DD was in gr. 1–10%, in gr. 2–30%, р <0.001. After treatment during a year this damages were saved. These data demonstrate, that Gly/Gly genotype of β1-adrenoreceptors gene can have cardioprotective effect leading to less of LV hypertrophy and diastolic dysfunction in patients with thyrotoxicosis.

A new approach for low-cost noninvasive detection of asymptomatic heart disease at rest.

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DeMarzo, Arthur P; Calvin, James E

2007-01-01

It would be useful to have an inexpensive, noninvasive point-of-care test for early detection of asymptomatic heart disease. This study used impedance cardiography (ICG) in a new way to assess heart function that did not use stroke volume or cardiac output. There is a model of the ICG dZ/dt waveform that may be used as a template to represent normal heart function. The hypothesis was that a dZ/dt waveform which deviates from that template should indicate heart dysfunction and therefore heart disease. The objective was to assess the accuracy of this new ICG approach, using echocardiography as the standard. Thirty-four outpatients undergoing echocardiographic testing were tested by ICG while sitting upright and supine. All patients had no symptoms or history of a structural or functional heart disorder. Echocardiographic testing showed 17 patients with abnormalities and 17 as normal. ICG testing yielded 16 true positives for heart dysfunction with 1 false negative (sensitivity = 94%) and 17 true negatives with no false positives (specificity = 100%). Considering that the cost, technical skill, and time required for this ICG test are comparable to those of an electrocardiograph, this new approach has potential as a point-of-care screening test for asymptomatic heart disease.

Responses to Exercise Differ For Chronic Fatigue Syndrome Patients with Fibromyalgia

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Cook, Dane B.; Stegner, Aaron J.; Nagelkirk, Paul R.; Meyer, Jacob D.; Togo, Fumiharu; Natelson, Benjamin H.

2011-01-01

Chronic fatigue syndrome (CFS) and fibromyalgia (FM) are chronic multisymptom illnesses with substantial clinical and diagnostic overlap. We have previously shown that when controlling for aerobic fitness and accounting for comorbid FM, CFS patients do not exhibit abnormal cardiorespiratory responses during maximal aerobic exercise compared to healthy controls, despite differences in pain and exertion. Purpose The purpose of the present study was to examine cardiac and perceptual responses to steady-state, submaximal exercise in CFS patients and healthy controls. Methods Twenty-one CFS patients [13 CFS with comorbid FM (CFS+FM)] and 14 controls completed 20 minutes of submaximal cycling exercise. Impedance cardiography was used to determine cardiac responses during exercise. Systolic blood pressure (SBP), perceived exertion (RPE) and leg-muscle pain were also measured. Data were analyzed using a doubly-multivariate, repeated-measures MANOVA to model the exercise response. Results There was a significant multivariate Time by Group interaction (p exercise response characterized by higher stoke index, ventilatory equivalents for oxygen and carbon dioxide and RPE, lower SBP and similar HR responses. Conclusions The present results extend upon our previous work with maximal exercise and show that CFS and CFS+FM differ in their responses to steady-state exercise. These results highlight the importance of accounting for comorbid conditions when conducting CFS research, particularly when examining psychophysiological responses to exercise. PMID:22157881

Accelerometer-determined physical activity and the cardiovascular response to mental stress in children.

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Spartano, Nicole L; Heffernan, Kevin S; Dumas, Amy K; Gump, Brooks B

2017-01-01

Cardiovascular reactivity has been associated with future hypertension and cardiovascular mortality. Higher physical activity (PA) has been associated with lower cardiovascular reactivity in adults, but little data is available in children. The purpose of this study was to examine the relationship between PA and cardiovascular reactivity to mental stress in children. Cross-sectional study. This study sample included children from the Oswego Lead Study (n=79, 46% female, 9-11 years old). Impedance cardiography was performed while children participated in a stress response protocol. Children were also asked to wear Actigraph accelerometers on their wrists for 3 days to measure intensity and duration of PA and sedentary time. In multivariable models, moderate to vigorous (MV) PA was associated with lower body mass index (BMI) percentile and lower total peripheral resistance (TPR) response to stress (beta=-0.025, p=0.02; beta=-0.009, p=0.05). After additional adjustment for BMI, MVPA was also associated with lower diastolic blood pressure response to stress (beta=-0.01, p=0.03). Total PA and sedentary time were not associated with BMI or cardiovascular responses to stress. A modest, inverse relation of PA to vascular reactivity to mental stress was observed in children. These data provide confirmatory evidence that the promotion of PA recommendations for children are important for cardiovascular health. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Higher exercise intensity delays postexercise recovery of impedance-derived cardiac sympathetic activity.

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Michael, Scott; Jay, Ollie; Graham, Kenneth S; Davis, Glen M

2017-08-01

Systolic time intervals (STIs) provide noninvasive insights into cardiac sympathetic neural activity (cSNA). As the effect of exercise intensity on postexercise STI recovery is unclear, this study investigated the STI recovery profile after different exercise intensities. Eleven healthy males cycled for 8 min at 3 separate intensities: LOW (40%-45%), MOD (75%-80%), and HIGH (90%-95%) of heart-rate (HR) reserve. Bio-impedance cardiography was used to assess STIs - primarily pre-ejection period (PEP; inversely correlated with cSNA), as well as left ventricular ejection time (LVET) and PEP:LVET - during 10 min seated recovery immediately postexercise. Heart-rate variability (HRV), i.e., natural-logarithm of root mean square of successive differences (Ln-RMSSD), was calculated as an index of cardiac parasympathetic neural activity (cPNA). Higher preceding exercise intensity elicited a slower recovery of HR and Ln-RMSSD (p return to baseline by 10 min following any intensity (p ≤ 0.009). Recovery of STIs was also slower following higher intensity exercise (p ≤ 0.002). By 30 s postexercise, higher preceding intensity resulted in a lower PEP (98 ± 14 ms, 75 ± 6 ms, 66 ± 5 ms for LOW, MOD, and HIGH, respectively, p fashion. While exercise intensity must be considered, acute recovery may be a valuable period during which to concurrently monitor these noninvasive indices, to identify potentially abnormal cardiac autonomic responses.

The non-invasive and continuous estimation of cardiac output using a photoplethysmogram and electrocardiogram during incremental exercise

International Nuclear Information System (INIS)

Wang, L; Poon, C C Y; Zhang, Y T

2010-01-01

Cardiac output (CO) monitoring is not only essential for critically ill patients in the hospital, but also for patients at home and those undergoing cardiopulmonary exercise testing. However, CO is difficult to monitor during daily activities and exercise. In this paper, we aim at developing a novel CO estimation method that can be used under these challenging conditions. The tube model was utilized to derive a CO index, namely the pulse time reflection ratio (PTRR) from an electrocardiogram and photoplethysmogram. After calibration, the PTRR can be used to estimate beat-to-beat CO. The proposed method was verified against CO measured by impedance cardiography on 19 healthy subjects in an incremental intensity exercise test. Results showed that there were strong correlations (r) between the PTRR and reference CO in 18 subjects (mean r: 0.88, n = 245 trials). Two calibration approaches reported in the literature were applied to the proposed method and the corresponding bias ± precisions of estimation errors were 0 ± 1.89 L min −1 and −0.22 ± 2.12 L min −1 , respectively. The percent errors were 21.94% and 24.90%, smaller than the clinical acceptance limit (30%). To conclude, after calibration, this method can be used to monitor CO on healthy subjects during incremental intensity exercise

Prenatal stress and balance of the child's cardiac autonomic nervous system at age 5-6 years.

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Aimée E van Dijk

Full Text Available OBJECTIVE: Autonomic nervous system (ANS misbalance is a potential causal factor in the development of cardiovascular disease. The ANS may be programmed during pregnancy due to various maternal factors. Our aim is to study maternal prenatal psychosocial stress as a potential disruptor of cardiac ANS balance in the child. METHODS: Mothers from a prospective birth cohort (ABCD study filled out a questionnaire at gestational week 16 [IQR 12-20], that included validated instruments for state anxiety, depressive symptoms, pregnancy-related anxiety, parenting daily hassles and job strain. A cumulative stress score was also calculated (based on 80(th percentiles. Indicators of cardiac ANS in the offspring at age 5-6 years are: pre-ejection period (PEP, heart rate (HR, respiratory sinus arrhythmia (RSA and cardiac autonomic balance (CAB, measured with electrocardiography and impedance cardiography in resting supine and sitting positions. RESULTS: 2,624 mother-child pairs, only single births, were available for analysis. The stress scales were not significantly associated with HR, PEP, RSA and CAB (p≥0.17. Accumulation of maternal stress was also not associated with HR, PEP, RSA and CAB (p≥0.07. CONCLUSION: Results did not support the hypothesis that prenatal maternal psychosocial stress deregulates cardiac ANS balance in the offspring, at least in rest, and at the age of five-six years.

The influence of social stress on time perception and psychophysiological reactivity.

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van Hedger, Kathryne; Necka, Elizabeth A; Barakzai, Anam K; Norman, Greg J

2017-05-01

Time perception is a fundamental component of everyday life. Although time can be measured using standard units, the relationship between an individual's experience of perceived time and a standard unit is highly sensitive to context. Stressful and threatening stimuli have been previously shown to produce time distortion effects, such that individuals perceive the stimuli as lasting for different amounts of time as compared to a standard unit. As a highly social species, humans are acutely sensitive to social stressors; however, time distortion effects have not been studied in the context of social stress. We collected psychophysiological (electrocardiogram and impedance cardiography) and time perception data before, during, and after a modified version of the Trier Social Stress Test for 42 participants. Based on prior theories and evidence from the time perception literature, we hypothesized that experiencing a stressful event would result in time distortion. This hypothesis was supported by the data, with individuals on average reproducing short and long duration negative and positive stimuli as lasting longer after experiencing social stress, t(41) = -3.55, p = .001, and t(41) = -4.12, p social stress. These findings are in line with some other studies of time distortion, and provide evidence for the interoceptive salience model of time perception. Implications for mechanisms of time distortion are discussed. © 2017 Society for Psychophysiological Research.

National radiology standards in X-ray diagnostic incl. interventional radiology

International Nuclear Information System (INIS)

Valek, V.; Kratochvil, P.

2005-01-01

In 2004 the Ministry of Health care started within the frame of the program for support of quality in health care a project consisting of 4 separate tasks: creating of standards for medical irradiation in radiodiagnostics, in radiotherapy , in nuclear medicine and creating of standards for patients dose assessment in radiophysics. This document continues with description of a part of the project aimed on X-ray radiodiagnostics. The authors of the project were chosen based on their bids to the public grant issued by the Ministry of Health care. The authors used recommendations, guidelines and instructions of international professional societies and IAEA, as well as the already existing procedures and practices while considering possibilities and state of the praxis in the Czech Republic. The outcome of authors work is now an interim version of a document that will be published in the bulletin of the Ministry of Health care. The document contains a set of standards that cover the whole range o fall complimentarily performed ways of patients irradiation in X-ray diagnostics and interventional radiology . The standards are divided to several categories according to the requirement of the Ministry of Health care based on the diagnostic appliances used for diagnostic irradiation i.e. radiography , fluoroscopy, mammography, stomatology, computer tomography, angiography, interventional radiography and cardiography. (authors)

Cognitive function in patients with stable coronary heart disease: Related cerebrovascular and cardiovascular responses.

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Gayda, Mathieu; Gremeaux, Vincent; Bherer, Louis; Juneau, Martin; Drigny, Joffrey; Dupuy, Olivier; Lapierre, Gabriel; Labelle, Véronique; Fortier, Annik; Nigam, Anil

2017-01-01

Chronic exercise has been shown to prevent or slow age-related decline in cognitive functions in otherwise healthy, asymptomatic individuals. We sought to assess cognitive function in a stable coronary heart disease (CHD) sample and its relationship to cerebral oxygenation-perfusion, cardiac hemodynamic responses, and [Formula: see text] peak compared to age-matched and young healthy control subjects. Twenty-two young healthy controls (YHC), 20 age-matched old healthy controls (OHC) and 25 patients with stable CHD were recruited. Cognitive function assessment included short term-working memory, perceptual abilities, processing speed, cognitive inhibition and flexibility and long-term verbal memory. Maximal cardiopulmonary function (gas exchange analysis), cardiac hemodynamic (impedance cardiography) and left frontal cerebral oxygenation-perfusion (near-infra red spectroscopy) were measured during and after a maximal incremental ergocycle test. Compared to OHC and CHD, YHC had higher [Formula: see text] peak, maximal cardiac index (CI max), cerebral oxygenation-perfusion (ΔO2 Hb, ΔtHb: exercise and recovery) and cognitive function (for all items) (Pcognitive inhibition and flexibility and long-term verbal memory (Pcognitive function (Pcognitive function (Pcognitive function, a similar cerebral oxygenation/perfusion during exercise but reduced one during recovery vs. their aged-matched healthy counterparts. In the all sample, cognitive functions correlated with [Formula: see text] peak, CI max and cerebral oxygenation-perfusion.

Early Poststroke Rehabilitation Using a Robotic Tilt-Table Stepper and Functional Electrical Stimulation

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Alexey N. Kuznetsov

2013-01-01

Full Text Available Background. Stroke frequently leaves survivors with hemiparesis. To prevent persistent deficits, rehabilitation may be more effective if started early. Early training is often limited because of orthostatic reactions. Tilt-table stepping robots and functional electrical stimulation (FES may prevent these reactions. Objective. This controlled convenience sample study compares safety and feasibility of robotic tilt-table training plus FES (ROBO-FES and robotic tilt-table training (ROBO against tilt-table training alone (control. A preliminary assessment of efficacy is performed. Methods. Hemiparetic ischemic stroke survivors (age years, days after stroke were assigned to 30 days of ROBO-FES (, ROBO (, or control ( in addition to conventional physical therapy. Impedance cardiography and transcranial doppler sonography were performed before, during, and after training. Hemiparesis was assessed using the British Medical Research Council (MRC strength scale. Results. No serious adverse events occurred; 8 patients in the tilt-table group prematurely quit the study because of orthostatic reactions. Blood pressure and CBFV dipped % during robot training. In 52% of controls mean arterial pressure decreased by %. ROBO-FES increased leg strength by points, ROBO by more than control (, . CBFV increased in both robotic groups more than in controls (. Conclusions. Robotic tilt-table exercise with or without FES is safe and may be more effective in improving leg strength and cerebral blood flow than tilt table alone.

Life Satisfaction and Hemodynamic Reactivity to Mental Stress.

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Schwerdtfeger, Andreas; Gaisbachgrabner, Kerstin; Traunmüller, Claudia

2017-06-01

Satisfaction with life has been considered a health-protective variable, which could impact cardiovascular morbidity and mortality. However, few studies have examined the physiological pathways involved in the potentially salutary effect of life satisfaction. It was hypothesized that life satisfaction should be associated with a cardiovascular response profile that signals challenge (i.e., higher cardiac output, lower peripheral resistance), rather than threat during a mental stress task. A sample of 75 healthy, medication-free men without clinical signs of psychological disorders who worked full-time and occupied highly demanding positions participated in this study. They performed two mental stress tasks (n-back) with varying degrees of difficulty. The tasks were embedded between a baseline and a recovery period. Cardiovascular and hemodynamic variables (heart rate, blood pressure, cardiac output, total peripheral resistance) were recorded by means of impedance cardiography. Individuals who were more satisfied with their life displayed higher cardiac output and lower peripheral resistance levels during the stress tasks, indicating a challenge rather than a threat profile. Findings were robust when controlled for physical activity, smoking, age, and depressive symptoms. Life satisfaction could be positively correlated with beneficial hemodynamic stress reactivity, indicating that individuals with higher levels of life satisfaction can more adaptively cope with stress. Increased cardiac output and decreased peripheral resistance during stress may constitute one route through which life satisfaction can benefit health.

Is blunted cardiovascular reactivity in depression mood-state dependent? A comparison of major depressive disorder remitted depression and healthy controls.

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Salomon, Kristen; Bylsma, Lauren M; White, Kristi E; Panaite, Vanessa; Rottenberg, Jonathan

2013-10-01

Prior work has repeatedly demonstrated that people who have current major depression exhibit blunted cardiovascular reactivity to acute stressors (e.g., Salomon et al., 2009). A key question regards the psychobiological basis for these deficits, including whether such deficits are depressed mood-state dependent or whether these effects are trait-like and are observed outside of depression episodes in vulnerable individuals. To examine this issue, we assessed cardiovascular reactivity to a speech stressor task and a forehead cold pressor in 50 individuals with current major depressive disorder (MDD), 25 with remitted major depression (RMD), and 45 healthy controls. Heart rate (HR), blood pressure and impedance cardiography were assessed and analyses controlled for BMI and sex. Significant group effects were found for SBP, HR, and PEP for the speech preparation period and HR, CO, and PEP during the speech. For each of these parameters, only the MDD group exhibited attenuated reactivity as well as impaired SBP recovery. Reactivity and recovery in the RMD group more closely resembled the healthy controls. Speeches given by the MDD group were rated as less persuasive than the RMD or healthy controls' speeches. No significant differences were found for the cold pressor. Blunted cardiovascular reactivity and impaired recovery in current major depression may be mood-state dependent phenomena and may be more reflective of motivational deficits than deficits in the physiological integrity of the cardiovascular system. Copyright © 2013 Elsevier B.V. All rights reserved.

Beat-by-beat analysis of cardiac output and blood pressure responses to short-term barostimulation in different body positions

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Hildebrandt, Wulf; Schütze, Harald; Stegemann, J.

Rapid quantification of the human baro-reflex control of heart rate has been achieved on a beat-by-beat basis using a neck-chamber with quick ECG-triggered pressure changes. Referring to recent findings on heart rate and stroke volume, the present study uses this technique to compare cardiac output as well as blood pressure changes in supine and upright position to investigate feedback effects and to confirm postural reflex modifications not revealed by RR-interval changes. A suction profile starting at +40 mmHg and running 7 steps of pressure decrease down to -65 mmHg was examined in 0° and 90° tilting position while beat-by-beat recordings were done of heart rate, stroke volume (impedance-cardiography) and blood pressure (Finapres tm) (n=16). The percentual heart rate decrease failed to be significantly different between positions. A suction-induced stroke volume increase led to a cardiac output almost maintained when supine and significantly increased when upright. A decrease in all blood pressure values was found during suction, except for systolic values in upright position which increased. Conclusively, (a) it is confirmed that different inotropy accounts for the seen gravitational effect on the cardiac output not represented by heart rate; (b) identical suction levels in different positions lead to different stimuli at the carotid receptor. This interference has to be considered in microgravity studies by beat-by-beat measurement of cardiac output and blood pressure.

Relationship between systemic hemodynamics and ambulatory blood pressure level are sex dependent.

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Alfie, J; Waisman, G D; Galarza, C R; Magi, M I; Vasvari, F; Mayorga, L M; Cámera, M I

1995-12-01

Sex-related differences in systemic hemodynamics were analyzed by means of cardiac index and systemic vascular resistance according to the level of daytime ambulatory blood pressure. In addition, we assessed the relations between ambulatory blood pressure measurements and systemic hemodynamics in male and female patients. We prospectively included 52 women and 53 men referred to our unit for evaluation of arterial hypertension. Women and men were grouped according to the level of daytime mean arterial pressure: or = 110 mm Hg. Patients underwent noninvasive evaluation of resting hemodynamics (impedance cardiography) and 24-hour ambulatory blood pressure monitoring. Compared with women men with lower daytime blood pressure had a 12% higher systemic vascular resistance index (P = NS) and a 14% lower cardiac index (P < .02), whereas men with higher daytime blood pressure had a 25% higher vascular resistance (P < .003) and a 21% lower cardiac index (P < .0004). Furthermore, in men systemic vascular resistance correlated positively with both daytime and nighttime systolic and diastolic blood pressures, whereas cardiac index correlated negatively only with daytime diastolic blood pressure. In contrast, women did not exhibit any significant correlation between hemodynamic parameters and ambulatory blood pressure measurements. In conclusion, sex-related differences in systemic hemodynamics were more pronounced in the group with higher daytime hypertension. The relations between systemic hemodynamics and ambulatory blood pressure level depended on the sex of the patient. In men a progressive circulatory impairment underlies the increasing level of ambulatory blood pressure, but this was not observed in women.

Comparison of dobutamine-stress magnetic resonance imaging and dipyridamole-Tl-201-SPECT as alternative strategies for the detection of coronary artery disease in patients not suitable for stress-echocardiography

International Nuclear Information System (INIS)

Schmidt, M.; Theissen, P.; Voth, E.; Schicha, H.; Jochims, M.; Baer, F.M.; Crnac, J.; Schneider, C.A.; Erdmann, E.

2001-01-01

Aim: During the past decade stress-echocardiography has gained increasing popularity for detection of myocardial ischemia in patients with coronary artery disease. However, about 10% to 15% of the patients submitted for stress-echocardiography do not have an adequate acoustic window. The purpose of this study was to compare high-dose dobutamine-stress magnetic resonance imaging (dobutamine-MRI) with dipyridamole-Tl-201-SPECT (dipyridamole-SPECT) as alternative strategies for detection of myocardial ischemia in patients with inadequate image quality by stress-echocardiography. Patients and Methods: Of 296 patients which were consecutively submitted to stress-echo-cardiography 45 patients (15%) had two or more segments that could not be evaluated according to the 16-segment-model of the American Society of Echocardiography. They underwent dobutamine-MRI and dipyridamole-SPECT studies, which were evaluated using a 28-segment modell. Myocardial segments were attributed to perfusion territories of the coronary arteries. The results of ischemia detection were compared to the results of coronary angiography (stenosis ≥50%). Results: In comparison to coronary angiography dobutamine-MRI yielded a sensitivity of 87%, a specificity of 86%, a positive predictive value of 93%, a negative predictive value of 75% and a diagnostic accuracy of 86%. For dipyridamole-SPECT results were 90%, 86%, 93%, 80% and 89%, respectively. These values were not significantly different. Conclusions: In patients not suitable for stress-echocardiography, both dobutamine-MRI and dipyridamole-SPECT are reliable strategies for detection of myocardial ischemia. Selection is dependent on the patient criteria, technical considerations, local logistics and experience of the observer. (orig.) [de

Metabolic and haemodynamic effects of oral glucose loading in young healthy men carrying the 825T-allele of the G protein β3 subunit

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Wenzel Rene R

2003-06-01

Full Text Available Abstract Background A C825T polymorphism was recently identified in the gene encoding the β3 subunit of heterotrimeric G-proteins (GNB3. The T-allele is significantly associated with essential hypertension and obesity. In order to further explore a possible pathogenetic link between the T-allele and impaired glucose tolerance we studied metabolic and haemodynamic responses to oral glucose loading in young, healthy subjects with and without the 825T-allele. Methods Twelve subjects with and 10 without the 825T-allele were investigated at rest and following glucose ingestion (75 g. Blood glucose, serum insulin and haemodynamics were determined prior to and over 2 hours following glucose ingestion. We non-invasively measured stroke volume (SV, by impedance-cardiography, blood pressure (BP, heart rate (HR, and systolic-time-intervals. Cardiac output (CO was calculated from HR and SV. Total peripheral resistance was calculated from CO and BP. Metabolic and haemodynamic changes were quantified by maximal responses and by calculation of areas under the concentration time profile (AUC. Significances of differences between subjects with and without the T-allele were determined by unpaired two-tailed t-tests. A p Results Metabolic and haemodynamic parameters at baseline were very similar between both groups. The presence of the T-allele did not alter the response of any metabolic or haemodynamic parameter to glucose loading. Conclusions In conclusion, this study does not support the hypothesis that the C825T polymorphism may serve as a genetic marker of early impaired glucose tolerance.

Effects of posture on upper and lower limb peripheral resistance following submaximal cycling.

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Swan, P D; Spitler, D L; Todd, M K; Maupin, J L; Lewis, C L; Darragh, P M

1989-09-01

The purpose of this study was to determine postural effects on upper and lower limb peripheral resistance (PR) after submaximal exercise. Twelve subjects (six men and six women) completed submaximal cycle ergometer tests (60% age-predicted maximum heart rate) in the supine and upright seated positions. Each test included 20 minutes of rest, 20 minutes of cycling, and 15 minutes of recovery. Stroke volume and heart rate were determined by impedance cardiography, and blood pressure was measured by auscultation during rest, immediately after exercise, and at minutes 1-5, 7.5, 10, 12.5, and 15 of recovery. Peripheral resistance was calculated from values of mean arterial pressure and cardiac output. No significant (p less than 0.05) postural differences in PR were noted during rest for either limb. Immediately after exercise, PR decreased (55% to 61%) from resting levels in both limbs, independent of posture. Recovery ankle PR values were significantly different between postures. Upright ankle PR returned to 92% of the resting level within four minutes of recovery, compared to 76% of the resting level after 15 minutes in the supine posture. Peripheral resistance values in the supine and upright arm were not affected by posture and demonstrated a gradual pattern of recovery similar to the supine ankle recovery response (85% to 88% of rest within 15 minutes). The accelerated recovery rate of PR after upright exercise may result from local vasoconstriction mediated by a central regulatory response to stimulation from gravitational pressure on lower body circulation.

Myocardial fatty acid imaging using iodine-123-BMIPP in patients with hypertensive intracranial hemorrhage

International Nuclear Information System (INIS)

Hashizume, Toshikazu; Sakai, Yasuhito; Hayashi, Yasushi

2000-01-01

An evaluation of myocardial fatty acid metabolism in hypertensive patients with major complication has not been previously established. To assess the myocardial fatty acid metabolism in hypertensive patients with intracranial hemorrhage (IH), we performed myocardial image using 123 I-15-p-iodophenyl-3-methyl pentadecanoic acid (BMIPP). Seventeen hypertensive patients with IH (HIH) and 27 hypertensive patients without IH (HT) were studied. A dose of 111 MBq of BMIPP was injected intravenously at rest, and a myocardial image was recorded 30 minutes after the injection. Myocardial perfusion image using Thallium-201 (Tl) was also performed within 2 weeks after BMIPP study. The regional myocardial uptakes of BMIPP and Tl were visually assessed in 17 segments with a four-point scoring system (0=absent to 3=normal uptake). Cardiac hypertrophy was evaluated by electrocardiogrpahy (ECG) and two-dimensional ultrasonic cardiography (UCG). Sum of uptake scores of Tl was similar in both groups (45.1±5.4 vs. 47.9±4.2), but that of BMIPP in HIH was lower than HT (35.9±7.9 vs 45.6±4.8, p<0.001). Evaluation of cardiac hypertrophy using ECG and UCG revealed no significant difference between two groups. HIH have much more eccentric hypertrophy in UCG study than HT (53% vs. 37%). These data suggest that hypertensive patients with intracranial hemorrhage have a more impaired myocardial fatty acid metabolism compared to the hypertensive patients with similar cardiac hypertrophy. BMIPP imaging might be useful to evaluate the severity of myocardial fatty acid metabolism in hypertensive patients. (author)

Influence of Child and Adult Elevated Blood Pressure on Adult Arterial Stiffness: The Cardiovascular Risk in Young Finns Study.

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Aatola, Heikki; Koivistoinen, Teemu; Tuominen, Heikki; Juonala, Markus; Lehtimäki, Terho; Viikari, Jorma S A; Raitakari, Olli T; Kähönen, Mika; Hutri-Kähönen, Nina

2017-09-01

Elevated blood pressure (BP) in childhood has been associated with increased adult arterial stiffness, the independent predictor of cardiovascular and all-cause mortality. The favorable BP change from childhood to adulthood and the risk of high adult arterial stiffness has not been reported. We examined the effect of child and adult BP on pulse wave velocity (PWV) assessed in adulthood among 1540 white adults followed-up for 27 years since baseline (1980, aged 6-18 years). Childhood elevated BP was defined according to the tables from the National High Blood Pressure Education Program. In adulthood, BP was classified as elevated if systolic BP ≥120 mm Hg, diastolic BP ≥80 mm Hg, or self-reported use of antihypertensive medications. PWV was measured in 2007 by whole-body impedance cardiography, and high PWV was defined as values at or above the age-, sex-, and heart rate-specific 80th percentile. Individuals with persistently elevated BP and individuals with normal child but elevated adult BP had increased risk of high adult PWV (relative risk [95% confidence interval], 3.18 [2.22-4.55] and 2.64 [1.79-3.88], respectively) in comparison with individuals with normal (both child and adult) BP. In contrast, individuals with elevated BP in childhood but not in adulthood did not have significantly increased risk of high PWV (relative risk [95% confidence interval], 1.26[0.80-1.99]). The results were consistent when different definitions for child and adult elevated BP were applied. These findings highlight the importance of BP control in the primary prevention of cardiovascular diseases. © 2017 American Heart Association, Inc.

Cardiac autonomic function and hot flashes among perimenopausal and postmenopausal women.

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Gibson, Carolyn J; Mendes, Wendy Berry; Schembri, Michael; Grady, Deborah; Huang, Alison J

2017-07-01

Abnormalities in autonomic function are posited to play a pathophysiologic role in menopausal hot flashes. We examined relationships between resting cardiac autonomic activity and hot flashes in perimenopausal and postmenopausal women. Autonomic function was assessed at baseline and 12 weeks among perimenopausal and postmenopausal women (n = 121, mean age 53 years) in a randomized trial of slow-paced respiration for hot flashes. Pre-ejection period (PEP), a marker of sympathetic activation, was measured with impedance cardiography. Respiratory sinus arrhythmia (RSA), a marker of parasympathetic activation, was measured with electrocardiography. Participants self-reported hot flash frequency and severity in 7-day symptom diaries. Analysis of covariance models were used to relate autonomic function and hot flash frequency and severity at baseline, and to relate changes in autonomic function to changes in hot flash frequency and severity over 12 weeks, adjusting for age, body mass index, and intervention assignment. PEP was not associated with hot flash frequency or severity at baseline or over 12 weeks (P > 0.05 for all). In contrast, there was a trend toward greater frequency of moderate-to-severe hot flashes with higher RSA at baseline (β = 0.43, P = 0.06), and a positive association between change in RSA and change in frequency of moderate-to-severe hot flashes over 12 weeks (β = 0.63, P = 0.04). Among perimenopausal and postmenopausal women with hot flashes, variations in hot flash frequency and severity were not explained by variations in resting sympathetic activation. Greater parasympathetic activation was associated with more frequent moderate-to-severe hot flashes, which may reflect increased sensitivity to perceiving hot flashes.

Prognostic value of noninvasive hemodynamic evaluation of the acute effect of levosimendan in advanced heart failure.

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Malfatto, Gabriella; Della Rosa, Francesco; Rella, Valeria; Villani, Alessandra; Branzi, Giovanna; Blengino, Simonetta; Giglio, Alessia; Facchini, Mario; Parati, Gianfranco

2014-04-01

Optimization of inotropic treatment in worsening heart failure sometimes requires invasive hemodynamic assessment in selected patients. Impedance cardiography (ICG) may be useful for a noninvasive hemodynamic evaluation. ICG was performed in 40 patients (69 ± 8 years; left ventricular ejection fraction 27.5 ± 5.6%; New York Heart Association 3.18 ± 0.34; Interagency Registry for Mechanically Assisted Circulatory Support 5.48 ± 0.96, before and after infusion of Levosimendan (0.1–0.2 µg/kg per min for up to 24 h). Echocardiogram, ICG [measuring cardiac index (CI), total peripheral resistances (TPRs) and thoracic fluid content (TFC)] and plasma levels of brain natriuretic peptide (BNP) were obtained; in nine patients, right heart catheterization was also carried out. When right catheterization and ICG were performed simultaneously, a significant relationship was observed between values of CI and TPR, and between TFC and pulmonary wedge pressure. ICG detected the Levosimendan-induced recovery of the hemodynamic status, associated with improved systolic and diastolic function and reduction in BNP levels. One-year mortality was 4.4%. At multivariate analysis, independent predictors of mortality were: no improvement in the severity of mitral regurgitation, a persistent restrictive filling pattern (E/E’ > 15), a reduction of BNP levels below 30% and a change below 10% in CI, TPR and TFC. When combined, absence of hemodynamic improvement at ICG could predict 1-year mortality with better sensitivity (86%) and specificity (85%) than the combination of echocardiographic and BNP criteria only (sensitivity 80% and specificity 36%). Noninvasive hemodynamic evaluation of heart failure patients during infusion of inodilator drugs is reliable and may help in their prognostic stratification.

Tissue Doppler echocardiography – A case of right tool, wrong use

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Thomas George

2004-08-01

Full Text Available Abstract Background The developments in echocardiography or ultrasound cardiography (UCG have improved our clinical capabilities. However, advanced hardware and software capabilities have resulted in UCG facilities of dubious clinical benefits. Is tissue Doppler echocardiography (TDE is one such example? Presentation of the hypothesis TDE has been touted as advancement in the field of echocardiography. The striking play of colors, impressive waveforms and the seemingly accurate velocity values could be deceptive. TDE is a clear case of inappropriate use of technology. Testing the hypothesis To understand this, a comparison between flow Doppler and tissue Doppler is made. To make clinically meaningful velocity measurements with Doppler, we need prior knowledge of the line of motion. This is possible in blood flow but impossible in the complex myocardial motion. The qualitative comparison makes it evident that Doppler is best suited for flow studies. Implications of the hypothesis As of now TDE is going backwards using an indirect method when direct methods are better. The work on TDE at present is only debatable 'research and publication' material and do not translate into tangible clinical benefits. There are several advances like curved M-mode, strain rate imaging and tissue tracking in TDE. However these have been disappointing. This is due to the basic flaw in the application of the principles of Doppler. Doppler is best suited for flow studies and applying it to tissue motion is illogical. All data obtained by TDE is scientifically incorrect. This makes all the published papers on the subject flawed. Making diagnostic decisions based on this faulty application of technology would be unacceptable to the scientific cardiologist.

Cerebro- and Cardio-vascular Responses to Energy Drink in Young Adults: Is there a Gender Effect?

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Monnard, Cathríona R; Montani, Jean-Pierre; Grasser, Erik K

2016-01-01

Energy drinks (EDs) are suspected to induce potential adverse cardiovascular effects and have recently been shown to reduce cerebral blood flow velocity (CBFV) in young, healthy subjects. Gender differences in CBFV in response to EDs have not previously been investigated, despite the fact that women are more prone to cardiovascular disturbances such as neurocardiogenic syncope than men. Therefore, the aim of this study was to explore gender differences in cerebrovascular and cardiovascular responses to EDs. We included 45 subjects in a retrospective analysis of pooled data from two previous randomized trials carried out in our laboratory with similar protocols. Beat-to-beat blood pressure, impedance cardiography, transcranial Doppler, and end-tidal carbon dioxide (etCO2) measurements were made for at least 20 min baseline and for 80 min following the ingestion of 355 mL of a sugar-sweetened ED. Gender and time differences in cerebrovascular and cardiovascular parameters were investigated. CBFV was significantly reduced in response to ED, with the greatest reduction observed in women compared with men (-12.3 ± 0.8 vs. -9.7 ± 0.8%, P < 0.05). Analysis of variance indicated significant time (P < 0.01) and gender × time (P < 0.01) effects. The percentage change in CBFV in response to ED was independent of body weight and etCO2. No significant gender difference in major cardiovascular parameters in response to ED was observed. ED ingestion reduced CBFV over time, with a greater reduction observed in women compared with men. Our results have potential implications for women ED consumers, as well as high-risk individuals.

Portable bioimpedance monitor evaluation for continuous impedance measurements. Towards wearable plethysmography applications.

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Ferreira, J; Seoane, F; Lindecrantz, K

2013-01-01

Personalised Health Systems (PHS) that could benefit the life quality of the patients as well as decreasing the health care costs for society among other factors are arisen. The purpose of this paper is to study the capabilities of the System-on-Chip Impedance Network Analyser AD5933 performing high speed single frequency continuous bioimpedance measurements. From a theoretical analysis, the minimum continuous impedance estimation time was determined, and the AD5933 with a custom 4-Electrode Analog Front-End (AFE) was used to experimentally determine the maximum continuous impedance estimation frequency as well as the system impedance estimation error when measuring a 2R1C electrical circuit model. Transthoracic Electrical Bioimpedance (TEB) measurements in a healthy subject were obtained using 3M gel electrodes in a tetrapolar lateral spot electrode configuration. The obtained TEB raw signal was filtered in MATLAB to obtain the respiration and cardiogenic signals, and from the cardiogenic signal the impedance derivative signal (dZ/dt) was also calculated. The results have shown that the maximum continuous impedance estimation rate was approximately 550 measurements per second with a magnitude estimation error below 1% on 2R1C-parallel bridge measurements. The displayed respiration and cardiac signals exhibited good performance, and they could be used to obtain valuable information in some plethysmography monitoring applications. The obtained results suggest that the AD5933-based monitor could be used for the implementation of a portable and wearable Bioimpedance plethysmograph that could be used in applications such as Impedance Cardiography. These results combined with the research done in functional garments and textile electrodes might enable the implementation of PHS applications in a relatively short time from now.

Rapid intravenous infusion of 20 mL/kg saline alters the distribution of perfusion in healthy supine humans.

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Henderson, A C; Sá, R C; Barash, I A; Holverda, S; Buxton, R B; Hopkins, S R; Prisk, G K

2012-03-15

Rapid intravenous saline infusion, a model meant to replicate the initial changes leading to pulmonary interstitial edema, increases pulmonary arterial pressure in humans. We hypothesized that this would alter lung perfusion distribution. Six healthy subjects (29 ± 6 years) underwent magnetic resonance imaging to quantify perfusion using arterial spin labeling. Regional proton density was measured using a fast-gradient echo sequence, allowing blood delivered to the slice to be normalized for density and quantified in mL/min/g. Contributions from flow in large conduit vessels were minimized using a flow cutoff value (blood delivered > 35% maximum in mL/min/cm(3)) in order to obtain an estimate of blood delivered to the capillary bed (perfusion). Images were acquired supine at baseline, after infusion of 20 mL/kg saline, and after a short upright recovery period for a single sagittal slice in the right lung during breath-holds at functional residual capacity. Thoracic fluid content measured by impedance cardiography was elevated post-infusion by up to 13% (pchanges in conduit vessels, there were no significant changes in perfusion in dependent lung following infusion (7.8 ± 1.9 mL/min/g baseline, 7.9 ± 2.0 post, 8.5 ± 2.1 recovery, p=0.36). There were no significant changes in lung density. These data suggest that saline infusion increased perfusion to nondependent lung, consistent with an increase in intravascular pressures. Dependent lung may have been "protected" from increases in perfusion following infusion due to gravitational compression of the pulmonary vasculature. Copyright © 2011 Elsevier B.V. All rights reserved.

Cognitive function in patients with stable coronary heart disease: Related cerebrovascular and cardiovascular responses.

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Mathieu Gayda

Full Text Available Chronic exercise has been shown to prevent or slow age-related decline in cognitive functions in otherwise healthy, asymptomatic individuals. We sought to assess cognitive function in a stable coronary heart disease (CHD sample and its relationship to cerebral oxygenation-perfusion, cardiac hemodynamic responses, and [Formula: see text] peak compared to age-matched and young healthy control subjects. Twenty-two young healthy controls (YHC, 20 age-matched old healthy controls (OHC and 25 patients with stable CHD were recruited. Cognitive function assessment included short term-working memory, perceptual abilities, processing speed, cognitive inhibition and flexibility and long-term verbal memory. Maximal cardiopulmonary function (gas exchange analysis, cardiac hemodynamic (impedance cardiography and left frontal cerebral oxygenation-perfusion (near-infra red spectroscopy were measured during and after a maximal incremental ergocycle test. Compared to OHC and CHD, YHC had higher [Formula: see text] peak, maximal cardiac index (CI max, cerebral oxygenation-perfusion (ΔO2 Hb, ΔtHb: exercise and recovery and cognitive function (for all items (P<0.05. Compared to OHC, CHD patients had lower [Formula: see text] peak, CI max, cerebral oxygenation-perfusion (during recovery and short term-working memory, processing speed, cognitive inhibition and flexibility and long-term verbal memory (P<0.05. [Formula: see text] peak and CI max were related to exercise cerebral oxygenation-perfusion and cognitive function (P<0.005. Cerebral oxygenation-perfusion (exercise was related to cognitive function (P<0.005. Stable CHD patients have a worse cognitive function, a similar cerebral oxygenation/perfusion during exercise but reduced one during recovery vs. their aged-matched healthy counterparts. In the all sample, cognitive functions correlated with [Formula: see text] peak, CI max and cerebral oxygenation-perfusion.

Nuclear stethoscope and myocard check-like computed method for loading experiments in the State Hospital for Cardiology, Balatonfuered, Hungary

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Horvath, M.; Boeszoermenyi, E.; Nemeth, L.; Kellenyi, L.; Karman, M.; Ludvigh, K.; Erdelyi, K.; Hajduczki, I.; Kantor, E. (Allami Szivkorhaz, Balatonfuered (Hungary))

1982-05-01

The radio-cyclographic technique (RCG) by ECG-triggered coherent averaging has been elaborated firstly for the presentation of cyclical fluctuation of the radioactive indicator in the heart during the equilibrium period. Later it was extended to other cardiac products, e.g. mechano-cardiography (M-CG). The stroke volume (SV) equivalence of the RCG's amplitude was verified first in Balatonfuered, by dye dilution comparative experiments (corr. coeff. 0.96 in the 40-75 ml/m/sup 2/ SV-index range). The pressure/volume paralellogram as expression of the momentary cardiac activity has been attempted from the right part of the heart by means of micro-catheterization and RCG, similarly was the RCG-volume and apex-CG 'pressure' loop processed; nowadays the derivation of the left ventricular systolic pressure pattern is attempted on the basis of RCG-volumetry. The ICA-70 multichannel analyser (KFKI) served for the A/D conversion analog curves, directly or from impulse-code modulated magnetic stores, in millisec time resolution. Apart from the averaging, the system can also be used for beat to beat analysis. The mathematical operations are: time interval histogram, smoothing of different cyclograms by Fourier processing giving also the accuracy of the fitting by corr. coeff. The program evaluates the time and velocity parameters, like PEP, LVET and their quotient in basal state and during bicycle ergometric load carried out in supine position, under influence of (cardiac) drugs. The program also serves for the volumetric control of the atrial diagnostic pacing and for arrhythmic analysis. RCG-measured SV-monitoring with simultaneous serum myoglobin level determination provides useful prognostic index (by their inverse relations) in the hyperacute state of AMI in the coronary care unit bedside.

A Thorax Simulator for Complex Dynamic Bioimpedance Measurements With Textile Electrodes.

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Ulbrich, Mark; Muhlsteff, Jens; Teichmann, Daniel; Leonhardt, Steffen; Walter, Marian

2015-06-01

Bioimpedance measurements on the human thorax are suitable for assessment of body composition or hemodynamic parameters, such as stroke volume; they are non-invasive, easy in application and inexpensive. When targeting personal healthcare scenarios, the technology can be integrated into textiles to increase ease, comfort and coverage of measurements. Bioimpedance is generally measured using two electrodes injecting low alternating currents (0.5-10 mA) and two additional electrodes to measure the corresponding voltage drop. The impedance is measured either spectroscopically (bioimpedance spectroscopy, BIS) between 5 kHz and 1 MHz or continuously at a fixed frequency around 100 kHz (impedance cardiography, ICG). A thorax simulator is being developed for testing and calibration of bioimpedance devices and other new developments. For the first time, it is possible to mimic the complete time-variant properties of the thorax during an impedance measurement. This includes the dynamic real part and dynamic imaginary part of the impedance with a peak-to-peak value of 0.2 Ω and an adjustable base impedance (24.6 Ω ≥ Z0 ≥ 51.6 Ω). Another novelty is adjustable complex electrode-skin contact impedances for up to 8 electrodes to evaluate bioimpedance devices in combination with textile electrodes. In addition, an electrocardiographic signal is provided for cardiographic measurements which is used in ICG devices. This provides the possibility to generate physiologic impedance changes, and in combination with an ECG, all parameters of interest such as stroke volume (SV), pre-ejection period (PEP) or extracellular resistance (Re) can be simulated. The speed of all dynamic signals can be altered. The simulator was successfully tested with commercially available BIS and ICG devices and the preset signals are measured with high correlation (r = 0.996).

Can echocardiographic findings predict falls in older persons?

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Nathalie van der Velde

Full Text Available BACKGROUND: The European and American guidelines state the need for echocardiography in patients with syncope. 50% of older adults with syncope present with a fall. Nonetheless, up to now no data have been published addressing echocardiographic abnormalities in older fallers. METHOD AND FINDINGS: In order to determine the association between echocardiographic abnormalities and falls in older adults, we performed a prospective cohort study, in which 215 new consecutive referrals (age 77.4, SD 6.0 of a geriatric outpatient clinic of a Dutch university hospital were included. During the previous year, 139 had experienced a fall. At baseline, all patients underwent routine two-dimensional and Doppler echocardiography. Falls were recorded during a three-month follow-up. Multivariate adjustment for confounders was performed with a Cox proportional hazards model. 55 patients (26% fell at least once during follow-up. The adjusted hazard ratio of a fall during follow-up was 1.35 (95% CI, 1.08-1.71 for pulmonary hypertension, 1.66 (95% CI, 1.01 to 2.89 for mitral regurgitation, 2.41 (95% CI, 1.32 to 4.37 for tricuspid regurgitation and 1.76 (95% CI, 1.03 to 3.01 for pulmonary regurgitation. For aortic regurgitation the risk of a fall was also increased, but non-significantly (hazard ratio, 1.57 [95% CI, 0.85 to 2.92]. Trend analysis of the severity of the different regurgitations showed a significant relationship for mitral, tricuspid and pulmonary valve regurgitation and pulmonary hypertension. CONCLUSIONS: Echo (Doppler cardiography can be useful in order to identify risk indicators for falling. Presence of pulmonary hypertension or regurgitation of mitral, tricuspid or pulmonary valves was associated with a higher fall risk. Our study indicates that the diagnostic work-up for falls in older adults might be improved by adding an echo (Doppler cardiogram in selected groups.

Exploring sexual dimorphism in placental circulation at 22-24 weeks of gestation: A cross-sectional observational study.

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Widnes, Christian; Flo, Kari; Acharya, Ganesh

2017-01-01

Placental blood flow is closely associated with fetal growth and wellbeing. Recent studies suggest that there are differences in blood flow between male and female fetuses. We hypothesized that sexual dimorphism exists in fetal and placental blood flow at 22-24 weeks of gestation. This was a prospective cross-sectional study of 520 healthy pregnant women. Blood flow velocities of the middle cerebral artery (MCA), umbilical artery (UA), umbilical vein (UV) and the uterine arteries (UtA) were measured using Doppler ultrasonography. UV and UtA diameters were measured using two-dimensional ultrasonography and power Doppler angiography. Volume blood flows (Q) of the UV and UtA were calculated. Maternal haemodynamics was assessed with impedance cardiography. UtA resistance (R uta ) was computed as MAP/Q uta . UA PI was significantly (p = 0.008) higher in female fetuses (1.19 ± 0.15) compared with male fetuses (1.15 ± 0.14). MCA PI, cerebro-placental ratio (MCA PI/UA PI), Q uv, UtA PI, Q uta and R uta were not significantly different between groups. At delivery, the mean birth weight and placental weight of female infants (3504 g and 610 g) were significantly (p = 0.0005 and p = 0.039) lower than that of the male infants (3642 g and 634 g). We have demonstrated sexual dimorphism in UA PI, a surrogate for placental vascular resistance, at 22-24 weeks of gestation. Therefore, it would be useful to know when this difference emerges and whether it translates into blood flow differences that may impact upon the fetal growth trajectory. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Successful transcatheter ablation of fascicular potential in pediatric patients with left posterior fascicular tachycardia].

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Zeng, Shao-ying; Shi, Ji-jun; Li, Hong; Zhang, Zhi-wei; Li, Yu-fen

2010-08-01

To simplify the methods of transcatheter mapping and ablation in the pediatric patients with left posterior fascicular tachycardia. While in sinus rhythm, the fascicular potential can be mapped at the posterior septal region (1 - 2 cm below inferior margin of orifice of coronary sinus vein), which display a biphasic wave before ventricular wave, and exist equipotential lines between them. When the fascicular potential occurs 20 ms later than the bundle of His' potential, radiofrequency was applied. Before applying radiofrequency, catheter position must be observed using double angle viewing (LAO 45°RAO 30°), and it should be made sure that the catheter is not at His' bundle. If the electrocardiogram displays left posterior fascicular block, the correct region is identified and ablation can continue for 60 s. Electrocardiogram monitoring should continue for 24 - 48 hours after operation, and notice abnormal repolarization after termination of ventricular tachycardia. Aspirin [2 - 3 mg/(kg·d)] was used for 3 months, and antiarrhythmic drug was discontinued. Surface electrocardiogram, chest X-ray and ultrasound cardiography were rechecked 1 d after operation. Follow-up was made at 1 month and 3 months post-discharge. Recheck was made half-yearly or follow-up was done by phone from then on. Fifteen pediatric patients were ablated successfully, and their electrocardiograms all displayed left posterior fascicular block after ablation. None of the patients had recurrences during the 3 to 12 months follow-up period. In one case, the electrocardiogram did not change after applying radiofrequency ablation and the ventricular tachycardia remained; however, on second attempt after remapping, the electrocardiogram did change. The radiofrequency lasted for 90 seconds and ablation was successful. This case had no recurrences at 6 months follow-up. Transcatheter ablation of the fascicular potential in pediatric patients with left posterior fascicular tachycardia can simplify

Nuclear stethoscope and myocard check-like computed method for loading experiments in the State Hospital for Cardiology, Balatonfuered, Hungary

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Horvath, M; Boeszoermenyi, E; Nemeth, L; Kellenyi, L; Karman, M; Ludvigh, K; Erdelyi, K; Hajduczki, I; Kantor, E [Allami Szivkorhaz, Balatonfuered (Hungary)

1982-05-01

The radio-cyclographic technique (RCG) by ECG-triggered coherent averaging has been elaborated firstly for the presentation of cyclical fluctuation of the radioactive indicator in the heart during the equilibrium period. Later it was extended to other cardiac products, e.g. mechano-cardiography (M-CG). The stroke volume (SV) equivalence of the RCG's amplitude was verified first in Balatonfuered, by dye dilution comparative experiments (corr. coeff. 0.96 in the 40-75 ml/m/sup 2/ SV-index range). The pressure/volume paralellogram as expression of the momentary cardiac activity has been attempted from the right part of the heart by means of micro-catheterization and RCG, similarly was the RCG-volume and apex-CG 'pressure' loop processed; nowadays the derivation of the left ventricular systolic pressure pattern is attempted on the basis of RCG-volumetry. The ICA-70 multichannel analyser (KFKI) served for the A/D conversion analog curves, directly or from impulse-code modulated magnetic stores, in millisec time resolution. Apart from the averaging, the system can also be used for beat to beat analysis. The mathematical operations are: time interval histogram, smoothing of different cyclograms by Fourier processing giving also the accuracy of the fitting by corr. coeff. The program evaluates the time and velocity parameters, like PEP, LVET and their quotient in basal state and during bicycle ergometric load carried out in supine position, under influence of (cardiac) drugs. The program also serves for the volumetric control of the atrial diagnostic pacing and for arrhythmic analysis. RCG-measured SV-monitoring with simultaneous serum myoglobin level determination provides useful prognostic index (by their inverse relations) in the hyperacute state of AMI in the coronary care unit bedside.

16. Optimal guidance of percutaneous device closure of PDA by transthoracic echocardiography

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M. Alobaidan

2016-07-01

Full Text Available Patent ductus arteriosus (PDA is common congenital cardiac lesion and the most accepted way of management is transcatheter occlusion by device which is usually done under fluoroscopy guidance. Transoesophageal echo cardiography and transaortic imaging were used in adult to guide the procedure which is with certain applications in pediatric age group transthoracic echocardiography (TTE in pediatric population provides excellent images for PDA and may replace the use of fluoroscopy to guide PDA closure at least in special situations. To highlight the feasibility of device closure under guidance of TTE to be applied in sick patients who are not suitable for transfer to cardiac catheter laboratory or those with contraindication to contrast and or radiation application. 18 patients from July 2013 to May 2015 underwent TTE guidance device closure of PDA, 1 patient was excluded after device embolization which necessitate retrieval under fluoroscopy (fluoro.. Conscious sedation was used in 17 patients except 1 who was sick and already ventilated in ICU, there were 11 female and 7 male, antegrade approach was used in 10 patients with partial fluoro and retrograde approach in 8 patients without fluoro. Median age is 7 months, median weight is 8 kg (3.2–11 kg, 2 patients with renal impairment, 2 with Leukemia, median procedure time is 35 min, median fluoro. is 2.2 min, PDA size were small in 13 patients and moderate in 5, immediate closure is achieved in all. The devices were ADOI, ADOS, ADOII, Occlutech, and AVP2. Device embolization in 1 with successful retrieval and second device was used with complete closure percutaneous PDA closure under TTE guidance is feasible, safe and recommended in selected patients with certain situation.

Difference in human cardiovascular response between upright and supine recovery from upright cycle exercise.

Science.gov (United States)

Takahashi, T; Okada, A; Saitoh, T; Hayano, J; Miyamoto, Y

2000-02-01

Cardiovascular responses were examined in seven healthy male subjects during 10 min of recovery in the upright or supine position following 5 min of upright cycle exercise at 80% peak oxygen uptake. An initial rapid decrease in heart rate (fc) during the early phase of recovery followed by much slower decrease was observed for both the upright and supine positions. The average fc at the 10th min of recovery was significantly lower (P position than in the upright position, while they were both significantly greater than the corresponding pre-exercise levels (each P positions was reduced with a decrease in mean R-R interval, the relationship being expressed by a regression line--mean R-R interval = 0.006 x HF amplitude + 0.570 (r = 0.905, n = 28, P positions is partly attributable to a retardation in the restoration of the activity of the cardiac parasympathetic nervous system. Post-exercise upright stroke volume (SV, by impedance cardiography) decreased gradually to just below the pre-exercise level, whereas post-exercise supine SV increased markedly to a level similar to that at rest before exercise. The resultant cardiac output (Qc) and the total peripheral vascular resistance (TPR) in the upright and supine positions returned gradually to their respective pre-exercise levels in the corresponding positions. At the 10th min of recovery, both average SV and Qc were significantly greater (each P position, while average TPR was significantly lower (P position. In contrast, immediately after exercise, mean blood pressure dropped markedly in both the supine and upright positions, and their levels at the 10th min of recovery were similar. Therefore we concluded that arterial blood pressure is maintained relatively constant through various compensatory mechanisms associated with fc, SV, Qc, and TPR during rest and recovery in different body positions.

Effects of Vestibular Loss on Orthostatic Responses to Tilts in the Pitch Plane

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Wood, Scott J.; Serrador, Jorge M.; Black, F. Owen; Rupert,Angus H.; Schlegel, Todd T.

2004-01-01

The purpose of this study was to determine the extent to which vestibular loss might impair orthostatic responses to passive tilts in the pitch plane in human subjects. Data were obtained from six subjects having chronic bilateral vestibular loss and six healthy individuals matched for age, gender, and body mass index. Vestibular loss was assessed with a comprehensive battery including dynamic posturography, vestibulo-ocular and optokinetic reflexes, vestibular evoked myogenic potentials, and ocular counterrolling. Head up tilt tests were conducted using a motorized two-axis table that allowed subjects to be tilted in the pitch plane from either a supine or prone body orientation at a slow rate (8 deg/s). The sessions consisted of three tilts, each consisting of20 min rest in a horizontal position, tilt to 80 deg upright for 10 min, and then return to the horizontal position for 5 min. The tilts were performed in darkness (supine and prone) or in light (supine only). Background music was used to mask auditory orientation cues. Autonomic measurements included beat-to-beat recordings of blood pressure (Finapres), heart rate (ECG), cerebral blood flow velocity in the middle cerebral artery (transcranial Doppler), end tidal CO2, respiratory rate and volume (Respritrace), and stroke volume (impedance cardiography). For both patients and control subjects, cerebral blood flow appeared to exhibit the most rapid adjustment following transient changes in posture. Outside of a greater cerebral hypoperfusion in patients during the later stages of tilt, responses did not differ dramatically between the vestibular loss and control subjects, or between tilts performed in light and dark room conditions. Thus, with the 'exception of cerebrovascular regulation, we conclude that orthostatic responses during slow postural tilts are not substantially impaired in humans following chronic loss of vestibular function, a result that might reflect compensation by nonvisual graviceptor

Nuclear stethoscope and myocard check-like computed method for loading experiments in the State Hospital for Cardiology, Balatonfuered, Hungary

International Nuclear Information System (INIS)

Horvath, M.; Boeszoermenyi, E.; Nemeth, L.; Kellenyi, L.; Karman, M.; Ludvigh, K.; Erdelyi, K.; Hajduczki, I.; Kantor, E.

1982-01-01

The radio-cyclographic technique (RCG) by ECG-triggered coherent averaging has been elaborated firstly for the presentation of cyclical fluctuation of the radioactive indicator in the heart during the equilibrium period, later it was extended to other cardiac products, e.g. mechano-cardiography (M-CG), too. The stroke volume (SV) equivalence of the RCG's amplitude was verified first in Balatonfuered, by dye dilution comparative experiments (corr. coeff. 0.96 in the 40-75 ml/m 2 SV-index range). The pressure/volume paralellogram as expression of the momentary cardiac activity has been attempted from the right part of the heart by means of micro-catheterization and RCG, similarly was the RCG-volume and apex-CG 'pressure' loop processed; nowadays the derivation of the left ventricular systolic pressure pattern is attempted on the basis of RCG-volumetry. The ICA-70 multichannel analyser (KFKI) served for the A/D conversion analog curves, directly or from impulse-code modulated magnetic stores, in millisec time resolution. Apart from the averaging, the system can also be used for beat to beat analysis. The other devices are also Hungarian-made: a four-channel radiocirculograph of Videoton, a desk calculator of the EMG type 666/B with 8 K memory, different nuclear instruments of the Gamma Works and a MEDICOR universal ergometer type KE-21. The mathematical operations are: time interval histogram, smoothing of different cyclograms by Fourier processing giving also the accuracy of the fitting by corr. coeff. The program evaluates the time and velocity parameters, like PEP, LVET and their quotient in basal state and during bicycle ergometric load carried out in supine position, under influence of (cardiac) drugs. The program also serves for the volumetric control of the atrial diaanostic pacing and for arrhythmic analysis. RCG-measured SV-monitoring with simultaneous serum myoglobin level determination provides useful prognostic index (by their inverse relations) in the

Echocardiography as an indication of continuous-time cardiac quiescence

Science.gov (United States)

Wick, C. A.; Auffermann, W. F.; Shah, A. J.; Inan, O. T.; Bhatti, P. T.; Tridandapani, S.

2016-07-01

Cardiac computed tomography (CT) angiography using prospective gating requires that data be acquired during intervals of minimal cardiac motion to obtain diagnostic images of the coronary vessels free of motion artifacts. This work is intended to assess B-mode echocardiography as a continuous-time indication of these quiescent periods to determine if echocardiography can be used as a cost-efficient, non-ionizing modality to develop new prospective gating techniques for cardiac CT. These new prospective gating approaches will not be based on echocardiography itself but on CT-compatible modalities derived from the mechanics of the heart (e.g. seismocardiography and impedance cardiography), unlike the current standard electrocardiogram. To this end, echocardiography and retrospectively-gated CT data were obtained from ten patients with varied cardiac conditions. CT reconstructions were made throughout the cardiac cycle. Motion of the interventricular septum (IVS) was calculated from both echocardiography and CT reconstructions using correlation-based, deviation techniques. The IVS was chosen because it (1) is visible in echocardiography images, whereas the coronary vessels generally are not, and (2) has been shown to be a suitable indicator of cardiac quiescence. Quiescent phases were calculated as the minima of IVS motion and CT volumes were reconstructed for these phases. The diagnostic quality of the CT reconstructions from phases calculated from echocardiography and CT data was graded on a four-point Likert scale by a board-certified radiologist fellowship-trained in cardiothoracic radiology. Using a Wilcoxon signed-rank test, no significant difference in the diagnostic quality of the coronary vessels was found between CT volumes reconstructed from echocardiography- and CT-selected phases. Additionally, there was a correlation of 0.956 between the echocardiography- and CT-selected phases. This initial work suggests that B-mode echocardiography can be used as a

Assessment of effects of differences in trunk posture during Fowler’s position on hemodynamics and cardiovascular regulation in older and younger subjects

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Kubota, Satoshi; Endo, Yutaka; Kubota, Mitsue; Shigemasa, Tomohiko

2017-01-01

Background Downward shifts in blood volume with changing position generally cause tachycardic responses. Age-related decreases in vagal nerve activity could contribute to orthostatic hypotension in older individuals. Fowler’s position is a reclined position with the back between 30° and 60°, used to facilitate breathing, eating, and other routine daily activities in frail and elderly patients. Objective This study examined whether stroke volume (SV) was higher and heart rate (HR) lower in Fowler’s position with an upright upper trunk than in Fowler’s position with the whole trunk upright in both older and younger subjects, based on the assumption that lower HR would result from reduced sympathetic activation in older individuals. Methods We assessed hemodynamics and HR variability from electrocardiography, noninvasive arterial pressure and impedance cardiography in 11 younger male subjects (age range, 20–22 years) and 11 older male subjects (age range, 64–79 years), using three positions: supine, or Fowler’s positions with either 30° of lower trunk inclination and 60° of upper trunk inclination (UT60) or 60° of whole trunk inclination (WT60). Comparisons were then made between age groups and between positions. Results Reductions in SV and tachycardic response were smaller with UT60 than with WT60, in both younger and older subjects. In addition, reduced tachycardic response with upright upper trunk appeared attributable to decreased vagal withdrawal in younger subjects and to reduced sympathetic activation in older subjects. Conclusion Our findings indicate that an upright upper trunk during Fowler’s position allowed maintenance of SV and inhibited tachycardic response compared to an upright whole trunk regardless of age, although the autonomic mechanisms underlying tachycardic responses differed between younger and older adults. An upright upper trunk in Fowler’s position might help to reduce orthostatic stress and facilitate routine

Comparison of Two Methods for Noninvasive Determination of Stroke Volume During Orthostatic Challenge

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Doerr, Donald F.; Ratliff, Duane A.; Sithole, Joseph; Convertino, Victor A.

2005-01-01

Background: The real time, beat-by-beat, non-invasive determination of stroke volume (SV) is an important parameter in many aerospace related physiologic protocols. In this study, we compared simultaneous estimates of SV calculated from peripheral pulse waveforms with a more conventional non-invasive technique. Methods: Using a prospective, randomized blinded protocol, ten males and nine females completed 12-mm tilt table protocols. The relative change (%(Delta)) in beat-to-beat SV was estimated non-invasively from changes in pulse waveforms measured by application of infrared finger photoplethysmography (IFP) with a Portapres(Registered TradeMark) blood pressure monitoring device and by thoracic impedance cardiography (TIC). The %(Delta) SV values were calculated from continuous SV measurements in the supine posture and over the first 10 s (T1), second 10 s (T2), and 3.5 minutes (T3) of 80deg head-up tilt (HUT). Results: The average %(Delta) SV measured by IFP at T1 (-11.7 +/- 3.7 %) was statistically less (P measured by TIC at T1 (-21.7 +/- 3.1 %), while the average %(Delta) SV measured by 1FF at T2 (-16.2 +/- 3.9 %) and T3 (-19.1 +/- 3.8 %) were not statistically distinguishable (P > or = 0.322) than the average %(Delta) SV measured by TIC at T2 (-21.8 +/- 2.5 %), and T3 (-22.6 +/- 2.9 %). Correlation coefficients (r(sup 2)) between IFP and TIC were 0.117 (T1), 0.387 (T2), and 0.7 18 (T3). Conclusion: IFP provides beat-to-beat (real time) assessment of %(Delta) SV after 20 sec of transition to an orthostatic challenge that is comparable to the commonly accepted TIC. Our data support the notion that IFP technology which has flown during space missions can be used to accurately assess physiological status and countermeasure effectiveness for orth static problems that may arise in astronauts after space flight. While the peripherally measured IFP response is slightly delayed, the ease of implementing this monitor in the field is advantageous.

Determinants of left ventricular diastolic dysfunction in hypertensive patients.

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Nazário Leão, R; Marques da Silva, P; Marques Pocinho, R; Alves, M; Virella, D; Palma Dos Reis, R

2018-02-02

The progression of hypertensive heart disease leads to the left ventricular diastolic dysfunction (LVDD), which is associated with increased cardiovascular morbidity and mortality. The purpose of this analysis is to explore the determinants for LVDD in patients with hypertension. This is a secondary analysis of data of Impedance Cardiography in the Evaluation of Left Ventricular Diastolic Dysfunction in Patients with Arterial Hypertension (IMPEDDANS) Study. Mann-Whitney and Chi-square tests were used for univariable analysis. Multiple logistic regression was used to model for LVDD occurrence and discriminative capacity of the model assessed by the value of the area under the curve given by the receiver-operating characteristic curve. Older age (65 vs. 58 years, p<0.001), longer duration of hypertension (160 vs. 48 months, p<0.001), uncontrolled hypertension (59.8 vs. 15.9%, p<0.001), tobacco smoking (17.8 vs. 3.8%, p=0.016), higher systolic blood pressure (133 vs. 124mmHg, p=0.001) and slower heart rate (62 vs. 66bpm, p=0.023) were associated with LVDD. Multivariate model identified uncontrolled hypertension (AdjOR 36.90; 95% CI 7.94-171.58; p<0.001), smoking (AdjOR 6.66; 95% CI 1.63-27.26; p=0.008), eccentric hypertrophy (AdjOR 3.59; 95% CI 0.89-14.39; p=0.072), duration of hypertension (AdjOR 1.03; 95% CI 1.02-1.05; p<0.001) and concentric remodeling (AdjOR 0.19; 95% CI 0.04-0.93; p=0.041) as the more determinant for occurrence of LVDD. The discriminative capacity of the model was AUC=0.95 (95% CI 0.91-0.98). The occurrence of LVDD in hypertensive patients was strongly associated to long-lasting, uncontrolled hypertension, tobacco smoking, concentric remodeling and eccentric hypertrophy. Copyright © 2017 SEH-LELHA. Publicado por Elsevier España, S.L.U. All rights reserved.

The significance of amlodipine on autonomic nervous system adjustment (ANSA method: A new approach in the treatment of hypertension

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Milovanović Branislav

2009-01-01

Full Text Available Introduction. Cardiovascular autonomic modulation is altered in patients with essential hypertension. Objective To evaluate acute and long-term effects of amlodipine on cardiovascular autonomic function and haemodynamic status in patients with mild essential hypertension. Methods. Ninety patients (43 male, mean age 52.12 ±10.7 years with mild hypertension were tested before, 30 minutes after the first 5 mg oral dose of amlodipine and three weeks after monotherapy with amlodipine. A comprehensive study protocol was done including finger blood pressure variability (BPV and heart rate variability (HRV beat-to-beat analysis with impedance cardiography, ECG with software short-term HRV and nonlinear analysis, 24-hour Holter ECG monitoring with QT and HRV analysis, 24-hour blood pressure (BP monitoring with systolic and diastolic BPV analysis, cardiovascular autonomic reflex tests, cold pressure test, mental stress test. The patients were also divided into sympathetic and parasympathetic groups, depending on predominance in short time spectral analysis of sympathovagal balance according to low frequency and high frequency values. Results. We confirmed a significant systolic and diastolic BP reduction, and a reduction of pulse pressure during day, night and early morning hours. The reduction of supraventricular and ventricular ectopic beats during the night was also achieved with therapy, but without statistical significance. The increment of sympathetic activity in early phase of amlodipine therapy was without statistical significance and persistence of sympathetic predominance after a few weeks of therapy detected based on the results of short-term spectral HRV analysis. All time domain parameters of long-term HRV analysis were decreased and low frequency amongst spectral parameters. Amlodipne reduced baroreflex sensitivity after three weeks of therapy, but increased it immediately after the administration of the first dose. Conclusion. The results

Diastolic pressure underestimates age-related hemodynamic impairment.

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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

Non-linear Heart Rate Variability as a Discriminator of Internalizing Psychopathology and Negative Affect in Children With Internalizing Problems and Healthy Controls

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Charlotte Fiskum

2018-05-01

Full Text Available Background: Internalizing psychopathology and dysregulated negative affect are characterized by dysregulation in the autonomic nervous system and reduced heart rate variability (HRV due to increases in sympathetic activity alongside reduced vagal tone. The neurovisceral system is however, a complex nonlinear system, and nonlinear indices related to psychopathology are so far less studied in children. Essential nonlinear properties of a system can be found in two main domains: the informational domain and the invariant domain. sample entropy (SampEn is a much-used method from the informational domain, while detrended fluctuation analysis (DFA represents a widely-used method from the invariant domain. To see if nonlinear HRV can provide information beyond linear indices of autonomic activation, this study investigated SampEn and DFA as discriminators of internalizing psychopathology and negative affect alongside measures of vagally-mediated HRV and sympathetic activation.Material and Methods: Thirty-Two children with internalizing difficulties and 25 healthy controls (aged 9–13 were assessed with the Child Behavior Checklist and the Early Adolescent Temperament Questionnaire, Revised, giving an estimate of internalizing psychopathology, negative affect and effortful control, a protective factor against psychopathology. Five minute electrocardiogram and impedance cardiography recordings were collected during a resting baseline, giving estimates of SampEn, DFA short-term scaling exponent α1, root mean square of successive differences (RMSSD, and pre-ejection period (PEP. Between-group differences and correlations were assessed with parametric and non-parametric tests, and the relationships between cardiac variables, psychopathology and negative affect were assessed using generalized linear modeling.Results: SampEn and DFA were not significantly different between the groups. SampEn was weakly negatively related to heart rate (HR in the controls

Cardiovascular regulation during water immersion.

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Park, K S; Choi, J K; Park, Y S

1999-11-01

Head-out water immersion at thermoneutral temperature (34-35 degrees C) increases cardiac output for a given O2 consumption, leading to a relative hyperperfusion of peripheral tissues. To determine if subjects immersed in water at a colder temperature show similar responses and to explore the significance of the hyperperfusion, cardiovascular functions were investigated (impedance cardiography) on 10 men at rest and while performing exercise on a leg cycle ergometer (delta M = approximately 95 W.m-2) in air and in water at 34.5 degrees C and 30 degrees C, respectively. In subjects resting in water, the cardiac output increased by approximately 50% compared to that in air, mainly due to a rise in stroke volume. The stroke volume change tended to be greater in 30 degrees C water than in 34.5 degrees C water, and this was due to a greater increase in cardiac preload, as indicated by a significantly greater left ventricular end-diastolic volume. Arterial systolic pressure rose slightly during water immersion. Arterial diastolic pressure remained unchanged in 34.5 degrees C water, but it rose in 30 degrees C water. The total peripheral resistance fell 37% in 34.5 degrees C water and 32% in 30 degrees C water. Both in air and in water, mild exercise increased the cardiac output, and this was mainly due to an increase in heart rate. Since, however, the stroke volume increased with water immersion, cardiac output at a given work load appeared to be significantly higher in water than in air. The arterial pressures did not decrease with water immersion, despite a marked reduction in total peripheral resistance. These results suggest that 1) during cold water immersion, peripheral vasoconstriction provides an additional increase in cardiac preload, leading to a further increase in the stroke volume compared to that of the thermoneutral water immersion, 2) the mechanism of cardiovascular adjustment during dynamic exercise is not changed by the persistent increase in cardiac

Assessment of effects of differences in trunk posture during Fowler’s position on hemodynamics and cardiovascular regulation in older and younger subjects

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Kubota S

2017-03-01

Full Text Available Satoshi Kubota,1 Yutaka Endo,1 Mitsue Kubota,1 Tomohiko Shigemasa2 1School of Nursing and Rehabilitation Sciences at Odawara, International University of Health and Welfare, Odawara, Kanagawa, Japan; 2Department of Cardiology, International University of Health and Welfare Atami Hospital, Atami, Shizuoka, Japan Background: Downward shifts in blood volume with changing position generally cause tachycardic responses. Age-related decreases in vagal nerve activity could contribute to orthostatic hypotension in older individuals. Fowler’s position is a reclined position with the back between 30° and 60°, used to facilitate breathing, eating, and other routine daily activities in frail and elderly patients. Objective: This study examined whether stroke volume (SV was higher and heart rate (HR lower in Fowler’s position with an upright upper trunk than in Fowler’s position with the whole trunk upright in both older and younger subjects, based on the assumption that lower HR would result from reduced sympathetic activation in older individuals. Methods: We assessed hemodynamics and HR variability from electrocardiography, noninvasive arterial pressure and impedance cardiography in 11 younger male subjects (age range, 20–22 years and 11 older male subjects (age range, 64–79 years, using three positions: supine, or Fowler’s positions with either 30° of lower trunk inclination and 60° of upper trunk inclination (UT60 or 60° of whole trunk inclination (WT60. Comparisons were then made between age groups and between positions. Results: Reductions in SV and tachycardic response were smaller with UT60 than with WT60, in both younger and older subjects. In addition, reduced tachycardic response with upright upper trunk appeared attributable to decreased vagal withdrawal in younger subjects and to reduced sympathetic activation in older subjects. Conclusion: Our findings indicate that an upright upper trunk during Fowler’s position allowed

[Clinical and experimental studies on the pathogenesis in pregnancy induced hypertension].

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Hidaka, A

1988-08-01

Placental ischemia is one of the etiological factors of pregnancy induced hypertension (PIH), however, the pathogenesis of placental and renal ischemia has not been clarified. The purposes of this investigation are (1) to clarify the fetomaternal hemodynamic changes in PIH and the influence of maternal postural change on fetomaternal hemodynamics, measured by thermodilution method, impedance cardiography and pulsed doppler method during pregnancy, (2) to provide to relationship between intrauterine resting tonus and maternal hemodynamics, that is, blood pressure, placental and renal blood flow measured by electromagnetic flowmeter and thermocouple method, and renal nerve activity, and (3) to study the influence of placental ischemia on vascular sensitivity to angiotensin II measured by Magnus method in animal experiment. (1) The increase in C.O and blood volume were recognized from the beginning of pregnancy to 24 GW, and subsequently, the decreasing tendency were found from about 32 GW to the onset of labor. However this decreasing tendency were subsided in the lateral position. These circulatory changes were observed in both normotensive and PIH cases, and especially, the decrease in C.O and blood volume in late pregnancy were more remarkable in PIH than that in normotensive pregnancy. From the results of Starling curve, left ventricular work was more hyperdynamic status in PIH than that in normotensive pregnancy, these results show that there are a compensatory mechanism against high vascular resistance in PIH. A/B (S/D) ratio in uterine artery, umbilical artery and fetal aorta were lowered in II-nd and III-rd trimester and more decreased in the lateral position from the supine position, on the other hand these ratio in PIH were elevated respectively. These results show that there are the aortocaval compression by the heavy tensive uterus and subsequent sluice flow mechanism in fetoplacental circulation in the supine position in late pregnancy. (2) These

A new electric method for non-invasive continuous monitoring of stroke volume and ventricular volume-time curves

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Konings Maurits K

2012-08-01

Full Text Available Abstract Background In this paper a new non-invasive, operator-free, continuous ventricular stroke volume monitoring device (Hemodynamic Cardiac Profiler, HCP is presented, that measures the average stroke volume (SV for each period of 20 seconds, as well as ventricular volume-time curves for each cardiac cycle, using a new electric method (Ventricular Field Recognition with six independent electrode pairs distributed over the frontal thoracic skin. In contrast to existing non-invasive electric methods, our method does not use the algorithms of impedance or bioreactance cardiography. Instead, our method is based on specific 2D spatial patterns on the thoracic skin, representing the distribution, over the thorax, of changes in the applied current field caused by cardiac volume changes during the cardiac cycle. Since total heart volume variation during the cardiac cycle is a poor indicator for ventricular stroke volume, our HCP separates atrial filling effects from ventricular filling effects, and retrieves the volume changes of only the ventricles. Methods ex-vivo experiments on a post-mortem human heart have been performed to measure the effects of increasing the blood volume inside the ventricles in isolation, leaving the atrial volume invariant (which can not be done in-vivo. These effects have been measured as a specific 2D pattern of voltage changes on the thoracic skin. Furthermore, a working prototype of the HCP has been developed that uses these ex-vivo results in an algorithm to decompose voltage changes, that were measured in-vivo by the HCP on the thoracic skin of a human volunteer, into an atrial component and a ventricular component, in almost real-time (with a delay of maximally 39 seconds. The HCP prototype has been tested in-vivo on 7 human volunteers, using G-suit inflation and deflation to provoke stroke volume changes, and LVot Doppler as a reference technique. Results The ex-vivo measurements showed that ventricular filling

Investigations of the Cardiovascular and Respiratory Systems on Board the International Space Station: Experiments Puls and Pneumocard

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Baranov, V. M.; Baevsky, R. M.; Drescher, J.; Tank, J.

parameters describing the results of the function of these systems like heart rate, arterial pressure, cardiac output, or breathing frequency, concentration of O2 and CO2 , etc. Missing significant changes of these parameters during weightlessness supports the hypothesis that adaptational and compensatory mechanisms are sufficient and guarantee cardiovascular homeostasis under changing environmental conditions. characteristic changes of the vegetative balance and of the activity of different regulatory elements at the brainstem and subcortical level. This changes guaranteed the adaptation to long term weightlessness. However, it remains unclear to what extent the different levels are involved. Moreover, the criteria describing the efficacy of cardiorespiratory interaction for the different functional states are not defined yet. The investigation of this problems is highly relevant in order to improve the medical control, especially if considering that the disruption of regulatory systems mostly precedes dangerous destruction of homeostasis. cardiovascular and respiratory function on Board the International Space Station (ISS) aiming to obtain new insights into the interaction between different regulatory elements. "Puls" is measures ECG, photoplethysmogram (PPG), and the pneumotachogram (PTG). The ECG is used to measure time series of R-R intervals and to analyse HRV. PPG is used to define the pulse wave velocity, phases of the cardiac cycle, and an estimate of the filling of finger vessels. The variability of these parameters is also calculated and compared to HRV. The analysis of the PTG allows to describe the interaction of the regulatory parameters of the cardiovascular and respiratory systems. Hence, an important feature of the experiment "Puls" is the investigation of regulatory mechanisms rather than of cardiovascular homeostasis. cardiography) and left ventricular contractility (seismocardiography) will be obtained. This expansion is of major importance

Maternal hemodynamics: a method to classify hypertensive disorders of pregnancy.

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Ferrazzi, Enrico; Stampalija, Tamara; Monasta, Lorenzo; Di Martino, Daniela; Vonck, Sharona; Gyselaers, Wilfried

2018-01-01

The classification of hypertensive disorders of pregnancy is based on the time at the onset of hypertension, proteinuria, and other associated complications. Maternal hemodynamic interrogation in hypertensive disorders of pregnancy considers not only the peripheral blood pressure but also the entire cardiovascular system, and it might help to classify the different clinical phenotypes of this syndrome. This study aimed to examine cardiovascular parameters in a cohort of patients affected by hypertensive disorders of pregnancy according to the clinical phenotypes that prioritize fetoplacental characteristics and not the time at onset of hypertensive disorders of pregnancy. At the fetal-maternal medicine unit of Ziekenhuis Oost-Limburg (Genk, Belgium), maternal cardiovascular parameters were obtained through impedance cardiography using a noninvasive continuous cardiac output monitor with the patients placed in a standing position. The patients were classified as pregnant women with hypertensive disorders of pregnancy who delivered appropriate- and small-for-gestational-age fetuses. Normotensive pregnant women with an appropriate-for-gestational-age fetus at delivery were enrolled as the control group. The possible impact of obesity (body mass index ≥30 kg/m 2 ) on maternal hemodynamics was reassessed in the same groups. Maternal age, parity, body mass index, and blood pressure were not significantly different between the hypertensive disorders of pregnancy/appropriate-for-gestational-age and hypertensive disorders of pregnancy/small-for-gestational-age groups. The mean uterine artery pulsatility index was significantly higher in the hypertensive disorders of pregnancy/small-for-gestational-age group. The cardiac output and cardiac index were significantly lower in the hypertensive disorders of pregnancy/small-for-gestational-age group (cardiac output 6.5 L/min, cardiac index 3.6) than in the hypertensive disorders of pregnancy/appropriate-for-gestational-age group

Situação da assistência médico-sanitária e hospitalar no Estado do Ceará, Brasil Medical care situation in the State of Ceara, Brazil

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João Yunes

1973-06-01

near to the required one unit per each 50,000 inhabitants. The qualitative appreciation, considered indirectly through the actual laboratory and human resources, seemed to be inefficient since only 16.7% of the health units have laboratory and 12.3% have no physicians; 21.7 (39 of the health center are closed because of the lack of this kind of professional related above. Paralel to this situation one can detect the existance of equipments completely out of date and the nearly absolute defficiency in the section of drug supply. From the 141 towns which compose the Region of Ceara, 31 (22% have no health unit and in 25 (17.7% we don't find any health resource. In the first presented case the population of medical care theoretically found out is of 378,449 inhabitants and in the second case it is of 232,900 inhabitants. From the 103 actual hospitals in this present Region 77.7% is on the responsability of the private section and 25% is concentrated in the capital of the Region. The quantitative standard of 1.84 beds/1000 inhabitants (7047 beds is extremely low when compared with the Brazilian average of 3.6 beds. The theoretically recomended average is 4.5 (beds. From the total number of beds 1.10/1000 are considered general and 0.74/1000 are specialized (tuberculosis, leprosy and psychiatry. The qualitative stantard of the hospital attendance is implicated since only 22.3% of the foundation have laboratory; 31.1% have X Ray apparatus and 11.6% present electro-cardiography. The most proeminent shortage of these resources occur in the countryside of this Region. More than 50.0% of the hospitals have no professional on health section, such us nursery, nutritionist, social work and technicians. From the 141 towns, 62.7% (89 have no hospitals, consequently about 1,300.000 inhabitants are theoretically in need of hospital care. Related to the 86 para-hospital units, through the lack of data is bigger, the situation is rather similar to the hospital care. There are 1207