[Contractility, pressure and volume reserve of pressure-hypertrophied hearts in situ].

In 18 adult mongrel dogs (24.6 kg) a statistically significant left ventricular hypertrophy (LVH) was induced by chronic aortic coarctation (180 days). In 12 anesthetized dogs (LVH 1) the effect of increasing doses of catecholamines on maximum contractility, expressed by (dp/dt)max, Vpm, t-(dp/dt)max was determined in comparison to a control group (KO 1; N = 6). There was no depression of the acute maximum contractility of hypertrophied hearts compared with the controls, also in respect to other haemodynamic parameters (SV/10 kg, HR, LVEP). In 6 other LVH-dogs (LVH 2) the maximum reached left ventricular pressure - obtained by complete clamping of the ascending aorta - was significantly higher. Either pressure per 100 g left ventricle did not differ significantly.