[Relations between ACE inhibition with captopril and atrial natriuretic factor during an acute hemodynamic study].

Aim of this study was to evaluate if captopril treatment may directly alter the trial natriuretic factor (ANF) concentration. Six patients (2 male and 4 female) aged 53 +/- 11 years, with mitral stenosis, and atrial fibrillation, underwent cardiac catheterization in our Institution. The following parameters were evaluated: heart rate, right atrial and pulmonary capillary wedge pressure, aortic and pulmonary pressure, cardiac index, pulmonary and systemic resistances and ANF concentration in coronary sinus, pulmonary, artery, aorta, peripheral vein. All these parameters were measured before and 30 and 60 min after captopril administration (50 mg orally). No hemodynamic changes occurred after captopril administration. No changes in ANF concentration occurred in comparison with baseline levels, after 30 and 60 min in coronary sinus (199.8 +/- 151.5 vs 181.9 +/- 102.5 fmol/ml; 178.4 +/- 95.2 vs 181.9 +/- 102.5 fmol/ml), in pulmonary artery (58.3 +/- 36.6 vs 51.4 +/- 48.8 fmol/ml; 35.5 +/- 16.9 vs 51.4 +/- 48.8 fmol/ml), in aorta (29.7 +/- 22.7 vs 37.5 +/- 26.3 fmol/ml; 25.2 +/- 9.8 vs 37.5 +/- 26.3 fmol/ml); and in peripheral vein (14.6 +/- 7.9 vs 17.3 +/- 9.7 fmol/ml; 16.2 +/- 12.2 vs 17.3 +/- 9.7 fmol/ml). In conclusion our data show that, providing no hemodynamic changes occur, captopril administration does not alter ANF concentration.