Effect of nitrates on the frequency of left ventricular free wall rupture complicating acute myocardial infarction: a case-controlled study.

Although up to 33% of all deaths from acute myocardial infarction are attributable to left ventricular free wall rupture, data showing a beneficial effect of drugs on this complication are scarce and contradictory. The aim of our study was to investigate the effect of nitrate therapy (intravenous or oral) during the first days after acute myocardial infarction on the frequency of free wall rupture in human beings. In a retrospective case-controlled study, 91 patients with free wall rupture complicating acute myocardial infarction demonstrated on autopsy or operation were compared with 182 control patients with acute myocardial infarction without rupture. The risk of sustaining free wall rupture was approximately 30% lower in patients receiving nitrates: (crude odds ratio 0.62; adjusted odds ratio 0.73 p 0.038). The data analysis demonstrates a possible association between nitrate use and frequency of left ventricular free wall rupture in patients with acute myocardial infarction. Nitrates seem to reduce the risk of rupture by approximately 30%.