[Quantitative echocardiographic study of the left ventricular function in acute aortic infective endocarditis].

Left ventricular (LV) function in 45 patients with native aortic valve infective endocarditis was studied in order to identify high surgical risk patients and the pattern of irreversible myocardial damage. LV function was studied by M-mode and 2D-echocardiography (LV volumes; ejection fraction, EF; peak systolic pressure to end-systolic volume ratio (PAP/ESV) as an index of myocardial contractility; LV mean systolic wall stress as an index of LV afterload and the radius to thickness ratio (R/Th). Thirteen patients underwent aortic valve replacement with an overall operative mortality of 15%. The cause of death was intractable heart failure. Different EF vs stress relationships could be described for different level of myocardial contractility: patients with intractable heart failure had a severely depressed myocardial contractility so that for a given level of LV stress, EF was significantly lower. High operative risk patients were identified by the PAP/ESV vs R/Th relation. All surgical deaths occurred in patients with a severely depressed myocardial contractility (PAP/ESV less than 2) and inadequate hypertrophy (R/Th greater than 4). Reversal of LV dysfunction in patients with moderately depressed myocardial contractility depended on the pattern of LV hypertrophy; a normal post-operative EF was achieved only in patients with adequate hypertrophy (R/Th less than 4).