[The effect isometric exertion on left ventricular function in patients after myocardial infarct]

24 patients, after transmural cardiac infarction, were exposed to isometric exercise ("handgrip"). The haemodynamic response was checked by means of impedance plethysmography. The stroke volume decreased on average from 64 +/- 14 to 60 +/- 15 ml (p less than 0.05), cardiac output increased from 4.8 +/- 1.0 to 5.4 +/- 1.2 l/min. (p less than 0.01). Peripheral resistance significantly increased and left ventricular performance was non-significantly reduced. Compared with a group of healthy control, their stroke and cardiac output and cardiac work kept increasing during isometric exercise. Isometric exercise is an adequate means of checking left ventricular performance.