Miloš Štejfa

Systolic and diastolic function in patients with chronic heart failure at rest and during exercise

In our study we tried to evaluate systolic and diastolic function in patients with chronic heart failure (CHF) by using some echocardiographic parameters and invasively measured pulmonary capillary wedge pressure (PCWP). We studied 19 patients with CHF NYHA II-III at rest, at the end of isometric exercise (handgrip) and during a bicycle stress test. Right heart catheterization and echocardiography were simultaneously performed. We measured exchange of blood gases, end diastolic volume (EDV), end systolic volume (ESV), ejection fraction (EF), peak E velocity, peak A velocity, E/A ratio, deceleration time of E wave (DT), time of mitral regurgitation (MR) and effective filling period of left ventricle (FP). We divided patients according to the median of PCWP at rest into two groups: group A with PCWP< or =11 mmHg (10 pts), group B with PCWP>11 mmHg (9 pts). In group A mean PCWP at rest was 6+/-2 mmHg, during handgrip 12+/-4 mmHg and during bicycle exercise 18+/-6 mmHg. In group B mean values of PCWP were 19+/-6 mmHg, 26+/-11 mmHg and 33+/-5 mmHg, respectively. All values were significantly higher in group B (P<0.01). There was a significant difference in pVO2: in group A 18.8+/-3.5 vs. 14.7+/-3.3 ml/kg per min in group B (P<0.03). No differences between the groups were noticed in EDV, ESV and EF. The E/A ratio in group A was less than 1, in group B greater than 1 with the restrictive pattern. No differences between the groups were observed in MR and FP at rest. During bicycle exercise, MR was significantly longer (284+/-98 vs. 164+/-79 ms; P<0.05) and FP shorter (322+/-99 vs. 421+/-74 ms; P<0.05) in group B than in group A. The functional capacity of patients with CHF is influenced not only by EF and other systolic variables, but also by filling conditions. The duration of effective diastole may be one of the most important of them.

Humoral response in patients with chronic heart failure

AIM Correlation of five humoral markers with laboratory, echocardiographic and right heart catheterization parameters in patients with chronic heart failure. STUDY POPULATION 29 patients, heart failure NYHA II and III, ejection fraction below 40% with coronary artery disease or dilated cardiomyopathy. METHODS evaluation of thromboxane, prostaglandin F (PGF), tumor necrosis factor (TNF) alpha, endothelin-1 and big endothelin rest levels and their correlation with: (1) laboratory parameters: Sodium, urea, creatinine, fibrinogen, (2) chest X-ray: cardiothoracic index (CTI), pulmonary congestion, (3) right heart catheterization parameters at rest, hand-grip and bicycle ergometry: mean pulmonary artery pressure (AP), wedge pressure (WP), systemic and pulmonary vascular resistance (SVR, PVR) and cardiac index (CI), (4) echocardiographic parameters at rest, hand-grip and bicycle ergometry: end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), mitral flow E/A, filling period of left ventricle and time of duration of mitral regurgitation. RESULTS No correlation was found between thromboxane, prostaglandin F and tumor necrosis factor alpha with the above mentioned parameters. Endothelin-1 level correlated with E/A, PVR and MPA at rest and at hand-grip. Big endothelin level correlated with EDV and ESV, AP, WP and SVR at rest and at both types of exercise. The highest correlation was between big endothelin and rest AP (r=0.79), rest WP (r=0.78) and CTI (r=0.58), all P<0.01. CONCLUSIONS Big endothelin and partly endothelin-1 levels showed a close correlation with some parameters used for the evaluation of chronic heart failure severity.

Amlodipine in patients with stable angina pectoris treated with nitrates and beta-blockers. The influence on exercise tolerance, systolic and diastolic functions of the left ventricle

The effects of 5 and 10 mg of amlodipine and of placebo were compared in 21 patients with stable angina pectoris and multivessel coronary artery disease. The blind comparison was performed by means of bicycle ergometry and stress echocardiography using esophageal stimulation of the left heart atrium. All patients subsequently received placebo, amlodipine 5 mg and 10 mg for 2 weeks. In bicycle ergometry both doses of amlodipine in comparison with placebo significantly lowered the ST segment depression in lead V5 and prolonged the time to onset of angina. The exercise duration was significantly prolonged only after 10 mg of amlodipine. In stress echocardiography 10 mg of amlodipine significantly improved ejection fraction and reduced wall motion score during stimulation and increased peak velocity of relaxation of left ventricular posterior wall at rest and immediately after stimulation. In the patients with left ventricular end-diastolic pressure < or = 20 mmHg, amlodipine reduced the ratio of peak transmitral flow velocity in atrial contraction to that in early diastole (A/E) at rest and shortened deceleration time at rest and immediately after stimulation. Amlodipine in patients with stable angina pectoris significantly improved the exercise tolerance and the function of the left ventricle in a dose-dependent way. Amlodipine was well tolerated.

Evaluation of autonomic nervous system dysfunction by phase shift and XYt graph methods

BACKGROUND: We postulated that the phase shift between blood pressure and heart rate fluctuation near the frequency of 0.10 Hz might be useful in assessing autonomic circulatory control. CONCLUSIONS: The frequency of 0.10 Hz represents a useful and potentially important one for controlled breathing, at which differences in blood pressure-RR interactions become evident. These interactions, whether computed as a variability of phase to define stability of the blood pressure-heart rate interaction or defined as the baroreflex sensitivity to define the gain in heart rate response to blood pressure changes, are significantly different in patients at risk for sudden arrhythmic death.

Depth of Breathing and Baroreflex Sensitivity

The aim of the study: Comparison between breathing on the 0.1 Hz and 0.33 Hz. At a breathing frequency of 0.10 Hz, differences in baroreflex sensitivity (P<0.01) became evident, even though these differences were not apparent at the 0.33-Hz breathing frequency. CONCLUSIONS: The frequency of 0.10 Hz represents a useful and potentially important one for controlled breathing, at which differences in blood pressure-RR interactions become evident. These measurements of short-term circulatory control might help in risk stratification for sudden cardiac death.