Isometric exercise in patients with chronic advanced heart failure: hemodynamic and neurohumoral evaluation

We evaluated the hemodynamic effects of isometric exercise in 53 patients with congestive heart failure (CHF) and compared them with those found in 10 normal subjects. In both groups, isometric exercise increased heart rate and blood pressure. Systemic resistance increased in patients with CHF (1862 +/- 520 vs 2126 +/- 642 dyne-sec-cm-5; p less than .001) but not in normal subjects (1359 +/- 268 vs 1380 +/- 252 dyne-sec-cm-5). Cardiac index and stroke volume index increased mildly but not significantly in the normal subjects (2.8 +/- 0.5 vs 3.1 +/- 0.7 liters/min/m2 and 46 +/- 8 vs 47 +/- 7 ml/m2) and showed a significant fall in the patients with CHF (2.1 +/- 0.6 to 1.9 +/- 0.6 liters/min/m2, p less than .01 and 23 +/- 7 vs 20 +/- 7 ml/m2, p less than .01). Mean pulmonary arterial wedge pressure increased in patients with CHF from 26 +/- 7 to 30 +/- 8 mm Hg (p less than .001). Although no significant change was found in mean value for stroke work index (21 +/- 9 vs 20 +/- 9 g-m/m2), the individual changes were variable, with marked decrease (greater than 15%) in 17 of the patients. This hemodynamic deterioration could not be predicted from resting hemodynamics, left ventricular ejection fraction, or functional classification. Isometric exercise resulted in no significant change in circulatory catecholamine levels or plasma renin concentration in our 10 normal subjects.(ABSTRACT TRUNCATED AT 250 WORDS)