Biomedical subjects

H Kelbaek

Publications and source records attributed to H Kelbaek.

113 records · Page 7Linked to original sources

PubMed1981

Spontaneous and/or training-induced haemodynamic changes after myocardial infarction.

Maximal oxygen uptake (VO2max) determinations and haemodynamic studies at rest and during two submaximal exercise levels (60 and 85% of the maximal) were performed in 30 male patients under 60 yr of age, 2, 5 and 8 mth after an uncomplicated myocardial infarction. Fourteen patients participated in a physical training programme during the first 3 mth of the study, while 16 patients attended the training during the second 3-mth period. An increase in VO2max occurred at 5 mth in both groups, 16 and 11%, respectively. Corresponding to this improvement cardiac index (CI) at the same relative submaximal work load increased similarly in the two groups. During the second period of the study only slight increments in VO2max and no salient alterations of the haemodynamics were recorded within or between the two groups. The linear relationship between oxygen uptake and CI was not affected throughout the study. As the work load was augmented from 60 to 85% of the maximal during the exercise test, the stroke volume index did not tend to fall. Our data suggest that allowing all patients to resume work in the very early rehabilitation period after an uncomplicated myocardial infarction, the improvement in physical work capacity and cardiac function is not significantly affected by a training programme of low intensity and short weekly duration.

Adult↗

PubMedDate not supplied

Acute effects of alcohol and food intake on cardiac performance.

Alcohol and food intake induce changes in LV performance which can be evaluated by radionuclide cardiographic methods. Alcohol probably exerts its effects by a direct action of ethanol in the blood on the myocardium, while the postprandial hemodynamic changes are related to the effects of food in the intestine. Alcohol intoxication causes a dose-dependent impairment of LV emptying at rest, whereas compensatory mechanisms other than an increased sympathetic nervous activity counterbalance this effect during exercise. In patients with coronary artery disease, alcohol induces only small changes in LV volumes at rest, possibly because of a concomitant vasodilation. Food intake seems to have a considerable influence on central hemodynamics leading to an increase in cardiac output both in healthy subjects and in patients with coronary artery disease. In healthy subjects an increase is recorded in the LVEDV and LVESV after a meal. The autonomic nervous system is probably responsible for most of the hemodynamic changes.

Alcoholic Intoxication↗

PubMedDate not supplied

Regional myocardial oxygen consumption estimated by carbon-11 acetate and positron emission tomography before and after repetitive ischemia.

BACKGROUND: Preserved myocardial oxygen consumption estimated by carbon 11-acetate and positron emission tomography (PET) in myocardial regions with chronic but reversibly depressed contractile function in patients with ischemic heart disease have been suggested to be caused by repeated short episodes of acute myocardial ischemia. To evaluate this hypothesis myocardial 11C-acetate PET imaging was performed before and after acute repetitive myocardial ischemia. METHODS AND RESULTS: In open chest dogs (n = 8), the left anterior descending coronary artery was occluded 4 times for 5 minutes alternating with 5 minutes of reperfusion. Before and after repetitive coronary occlusions, oxygen 15 water/oxygen 15 carbon monoxide (blood flow), and 11C-acetate (oxygen consumption) PET imaging were performed. Left ventricular regional systolic wall thickening was measured with sonomicrometry. Forty-five minutes after the ischemic episodes, systolic ventricular wall thickening was decreased by 90%, whereas myocardial blood flow was reduced by 21% compared with baseline values (P < .05). Ninety minutes after the ischemic episodes, estimated oxygen consumption was unaltered compared with the baseline level despite a sustained 70% decrease in the regional contractile function (P < .05). CONCLUSIONS: Oxygen consumption estimated by 11C-acetate PET imaging is preserved after repeated episodes of acute myocardial ischemia despite a severe impairment of contractile function.

Acetates↗

PubMedDate not supplied

Age and left ventricular ejection fraction identify patients with advanced breast cancer at high risk for development of epirubicin-induced heart failure.

BACKGROUND: To evaluate the possibility of predicting development of heart failure, we monitored left ventricular ejection fraction (LVEF) in addition to demographic data in patients with advanced breast cancer treated with epirubicin. METHODS AND RESULTS: LVEF determination by radionuclide angiocardiography was performed serially before, during, and after treatment with 130 mg epirubicin/m2 every 3 weeks until disease progression or a cumulative dose of 1000 mg/m2 was reached (or heart failure occurred). Among 67 patients, heart failure developed in eight (12%). Age was 5 to 8 years greater and baseline LVEF was 7% less (95% confidence interval 3% to 13%) in patients who had heart failure than in the remaining patients. LVEF was slightly reduced in all patients during treatment. Three combined criteria, age > or =50 years, baseline LVEF < or =0.60, and decrease in LVEF to 0.50, had a positive predictive value of 70% (95% confidence interval 35% to 93%) and a negative predictive value of 98% (95% confidence interval 90% to 100%) with respect to development of heart failure. Conventional LVEF criteria were of less diagnostic value. CONCLUSIONS: Our results indicate that age and baseline LVEF determination mark a group of patients at high risk for development of epirubicin-induced heart failure. Monitoring of serial LVEF is indicated during treatment of these patients.

Adult↗

PubMedDate not supplied

Non-invasive measurement of stroke volume and left ventricular ejection fraction. Radionuclide cardiography compared with left ventricular cardioangiography.

The stroke volume (SV) was determined by first passage radionuclide cardiography and the left ventricular ejection fraction (LVEF) by multigated radionuclide cardiography in 20 patients with ischemic heart disease. The results were evaluated against those obtained by the invasive dye dilution or thermodilution and left ventricular cardioangiographic techniques. In a paired comparison the mean difference between the invasive and radionuclide SV was -1 ml (SED 3.1) with a correlation coefficient of 0.83 (p less than 0.01). Radionuclide LVEF values also correlated well with cardioangiographic measurements, r = 0.93 (p less than 0.001). LVEF determined by multigated radionuclide cardiography was, however, significantly lower than when measured by cardioangiography, the mean difference being 6 per cent (p less than 0.001). These findings suggest that radionuclide determinations of SV and LVEF are reliable. The discrepancy between the non-invasive and invasive LVEF values raises the question, whether LVEF is overestimated by cardioangiography or underestimated by radionuclide cardiography.

Adult↗