[Anomalies in left ventricular systolic function disclosed by exercise testing in chronic aortic insufficiency. Study...

Fifty-two patients with a symptomatic chronic aortic insufficiency underwent radionuclide angiography. The following parameters were measured at rest and at peak exercise: ejection fraction, regurgitant fraction, ventricular volumes, stroke volume, cardiac output and an index of systemic arterial resistance. The ventricular dimensions, the thickness of the septal and posterior walls, left ventricular myocardial mass and endsystolic stress were determined by 2D echocardiography. The patients were divided into 3 groups based on left ventricular changes on exercise: the first group (18 patients) had physiological left ventricular adaptation to exercise (increased ejection fraction, reduced endsystolic volume); a second group of 18 patients had moderate left ventricular dysfunction (absence of increase in ejection fraction and a reduction of less than 20% of endsystolic volume with respect to basal values); a third group of 17 patients had what was considered to be severe left ventricular dysfunction (decreased ejection fraction of over 5% and increased endsystolic volume of over 20% with respect to basal values). There was no significant difference between the three groups with respect to basal values of ejection fraction, ventricular volumes and systemic arterial resistance. On exercise, the heart rate, blood pressure and systemic arterial resistances varied in a comparable manner in each of the three groups. The left ventricular dimensions and myocardial mass were identical in the three groups. Only left ventricular endsystolic strain tended to be higher in the third group of patients compared with the other two, but the difference was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)