title: Effect of isometric exercise on cardiac performance and mitral regurgitation in patients with severe congestive heart failure.
abstract: Left ventricular performance was studied during isometric exercise in 17 patients with severe congestive heart failure, combining invasive hemodynamic and echo-Doppler techniques. Isometric exercise at 30% of maximum resulted in a decrease in stroke volume index (27.4 +/- 7.1 to 22.7 +/- 7.4 ml/m2), with a significant increase in heart rate from 81 +/- 10 to 92 +/- 14 beats/min and in systemic vascular resistance from 1827 +/- 527 to 2372 +/- 737 dyne.sec.cm-5. A significant rise in pulmonary capillary wedge pressure (18 +/- 9 to 31 +/- 10 mm Hg) was associated with a marked increase in mitral regurgitant volume (14 +/- 11 to 27 +/- 15 ml), calculated as the difference between total stroke volume obtained by two-dimensional echocardiography and forward stroke volume measured by pulsed Doppler at the aortic anulus. During isometric exercise, left ventricular end-diastolic and end-systolic volumes did not change markedly, but the total stroke volume tended to increase from 62 +/- 13 to 67 +/- 13 ml. The increase in mitral regurgitant volume induced by isometric exercise was correlated with the fall in forward stroke volume (r = 0.7, p less than 0.01). Thus a rise in systemic arterial pressure induced by isometric exercise is associated with a decrease in cardiac performance attributable to redistribution of total left ventricular output with an increase in mitral regurgitation and a simultaneous decrease in forward cardiac output.
authors.affiliation: Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461.
authors.forename: G
authors.initials: G
authors.lastname: Keren
authors.forename: S
authors.initials: S
authors.lastname: Katz
authors.forename: J
authors.initials: J
authors.lastname: Gage
authors.forename: J
authors.initials: J
authors.lastname: Strom
authors.forename: E H
authors.initials: EH
authors.lastname: Sonnenblick
authors.forename: T H
authors.initials: TH
authors.lastname: LeJemtel
mesh_terms: D000368:Aged; D006328:Cardiac Catheterization; D015150:Echocardiography, Doppler; D015444:Exercise; D005260:Female; D006321:Heart / Q000503:physiopathology*; D006333:Heart Failure / Q000150:complications / Q000503:physiopathology*; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000150:complications / Q000503:physiopathology*; D013815:Thermodilution