Mitral valve surgery for acute papillary muscle rupture following myocardial infarction

BACKGROUND AND AIM OF THE STUDY: Acute papillary muscle rupture (PMR) is a rare but fatal complication of myocardial infarction (MI). Surgery represents the best treatment option, but carries a high risk. Our experience of emergency mitral valve surgery in patients with acute PMR following MI during the past 22 years is reviewed. METHODS: Between 1978 and 2000, 33 patients (20 males, 13 females; mean age 64 years; range: 46-80) underwent emergency surgery for acute post-infarct PMR in our institution. The site of MI was anterior in three patients and inferior in 30. Preoperatively, 17 patients had an intra-aortic balloon pump (IABP) inserted, 26 were on inotropic support, and 17 were ventilated. Twenty patients (61%) underwent concomitant coronary bypass grafting (CABG). The valve was replaced in 31 patients and repaired in two. Mean (+/- SD) duration of follow up was 63+/-54 months (range: 0-183 months). RESULTS: Early mortality (in-hospital) was 21% (n = 7). Factors associated with significant risk of early mortality included raised preoperative serum creatinine (p = 0.02), need for preoperative inotropic support (p = 0.03) and preoperative ventilation (p = 0.03). Raised preoperative serum creatinine remained significant on multiple logistic regression (p = 0.04). Postoperatively, 21 patients required an IABP. Mean duration of intensive care unit stay was 4+/-2.5 days (range: 0-10 days). Survival, including in-hospital mortality, at one, five and 10 years was 75+/-7.4, 65+/-8.6 and 32+/-9.7%, respectively. Four patients required valve-related reoperation (three for a paraprosthetic leak, one for failed repair). CONCLUSION: Patients with acute post-infarct PMR present in a severely compromised state. Early mortality is high, but the intermediate outcome is encouraging for operative survivors.