Aims: Information regarding the cardiorenal axis in patients after a myocardial infarction (MI) is limited. We examined the change in renal function after a first MI, the protective effect of angiotensin converting enzyme (ACE) inhibition and the prognostic value of baseline renal function.
Methods and results: The study population consisted of 298 patients with a first anterior wall MI who were randomized to the ACE inhibitor captopril or placebo after completion of streptokinase infusion. Renal function, by means of glomerular filtration rate (GFR), was calculated using the Cockroft-Gault equation (GFR(c)). In the placebo group, renal function (GFR(c)) declined by 5.5 min(-1)within 1 year, vs only 0.5 ml min(-1)in the ACE inhibitor group (P<0.05). This beneficial effect of captopril was most pronounced in patients with the most compromised renal function at baseline. The incidence of chronic heart failure (CHF) within 1 year increased significantly with decreasing GFR(c)(divided into tertiles: 24.0, 28.9, and 41.2%; P<0.01). The risk-ratio for GFR(c)<81 ml min(-1)vs >103 mL min(-1)was 1.86 (95% CI 1.11-3.13; P=0.019).
Conclusions: Renal function markedly deteriorates after a first MI, but is significantly preserved by ACE inhibition. Furthermore, an impaired baseline renal function adds to the prognostic risk of developing CHF in patients after a first anterior MI.