PLASMA-RENIN ACTIVITY IN CHAGASIC PATIENTS WITH AND WITHOUT CONGESTIVE-HEART-FAILURE

Chagasic patients with advanced heart disease have fluid retention-dep endent symptoms. Since fluid retention is mostly dependent on the reni n-angiotensin-aldosterone system, chagasic patients with congestion re lated symptoms should have activation of the renin-angiotensin-aldoste rone system. The purpose of this investigation was to determine the pl asma renin activity baseline values of chagasic patients with and with out congestive heart failure. Twenty-eight patients with positive sero logy for Chagas' disease were studied. Nineteen patients were asymptom atic (functional class I New York Heart Association) and nine were sym ptomatic (functional classes II-IV). Cardiac catheterization and ventr icular cineangiography were performed on 20 patients. The symptomatic patients had significantly higher plasma renin activity levels (4.11 /- 1.03 ng/ml/h) than the asymptomatic patients (1.08 +/- 0.11 ng/ml/h , P < 0.001) and the normal sedentary controls (1.65 +/- 0.22 ng/ml/h, P < 0.05, mean +/- S.E.). The plasma renin activity baseline values o f the asymptomatic and symptomatic patients correlated directly with t he baseline heart rate (r = 0.77, P < 0.0001). The symptomatic patient s had larger ventricular volumes, moderately depressed ejection fracti ons and increased left ventricular end-diastolic pressures. The plasma renin activity baseline values also correlated directly with the left ventricular diastolic pressures (r = 0.70, P < 0.0006) and with the l eft ventricular diastolic (r = 0.66, P < 0.001) and systolic volumes ( r = 0.67, P < 0.001). These results indicate that chagasic patients wi th fluid retention-dependent symptoms and hemodynamic evidence of left ventricular systolic dysfunction have activation of the renin-angiote nsin-aldosterone system.