BACKGROUND ventricular septal rupture is a rare complication of myocardial infarction. It is considered the most serious mechanical disturbance in these cases. The mortality of patients during the hospital period receiving surgical treatment for this complication is described. METHODS a case series study, including patients with ventricular septal rupture posterior to myocardial infarction, detected with a retrospective review of records of patients subjected to surgical repair from December 2005 to December 2010. RESULTS a total of 20 patients were included, with an average age of 56 years (48-65 years), male gender in 16 cases (80%), and a male: female relation of 4:1. Ten (50%) of the patients died; five due to multiple organ failure, one from nosocomial pneumonia, two from ventricular fibrillation, and two from refractory shock secondary to biventricular failure during the surgery. The factors identified for poor prognosis were the average time of 145 minutes on cardiopulmonary bypass, and acute kidney injury in six cases, requiring replacement therapy. CONCLUSIONS ventricular septal rupture is a rare complication with a high mortality. Without surgical treatment mortality can reach almost 100%. The mortality of this pathology treated with surgical closing in our hospital was 50%, similar to other published reports. Our findings confirm that although surgery for ventricular septal rupture has a high mortality it should be carried out because it is a surgical emergency.