Mechanical complications after acute myocardial infarction: a 15-year single-center experience

Introduction

Acute myocardial infarction (AMI) can lead to mechanical complications (MC) from rupture or tearing of infarcted myocardium. Their presentation depends on whether the rupture is complete or contained, and on the structure involved—free wall, septum, or papillary muscles. Although uncommon, MCs carry very high mortality and remain insufficiently described. This study reviews MC cases in a single tertiary center, focusing on presentation, management, and in-hospital outcomes.

Methods

This retrospective observational study reviewed records from 2010 to 2025. Patients were included if they developed an MC after admission for MI and were managed at this center with available clinical data. The primary endpoint was in-hospital mortality.

Results

Among 104 MC cases post-AMI, 56% were male and mean age was 72 ± 11 years. Coronary angiography was performed in 81% of patients, but only 62% within 24 hours of symptom onset. Revascularization was complete in 31%, incomplete in 22%, and not attempted in 47%, largely due to non-viable myocardium and multivessel disease.

MC types were ventricular septal defect (VSD) in 44%, acute severe mitral regurgitation (MR) in 21%, pseudoaneurysm in 21%, and free wall rupture (FWR) in 14% (one had both MR and FWR). At diagnosis, 58% were in cardiogenic shock, and 50% required mechanical circulatory support (IABP 84%, ECMO 4%, both 12%). Surgery was performed in 67% (CABG in 21%), with a median symptom-to-surgery time of 3 days (IQR 1–10). In-hospital mortality was 50% and 58% at 1 year. Surgical management achieved 76% in-hospital survival versus only 6% in non-operated patients.

In patients with MR (n=22), 32% required preoperative IABP and 9% needed combined IABP–ECMO support. Nearly two-thirds underwent surgery, with in-hospital mortality of 45%; all survivors had surgery.

Among those with VSD (n=46), defects were apical in 50% and basal/posterior in 41%, 9% mid-septal. Mechanical support was common (IABP 32%, IABP + ECMO 9%), and 74% underwent surgical repair (26% requiring reoperation). In-hospital mortality was 52%, with only one survivor managed conservatively.

Pseudoaneurysm (n=22) had had the most favorable outcome : 82% were surgically repaired, yielding an in-hospital mortality of 22%, with only one non-operative survivor.

Free wall rupture (n=15) carried the worst prognosis. Only 40% underwent surgery. Overall survival was 7%, only one patient who underwent surgical repair.

Conclusion

Mechanical complications are rare but highly lethal post-MI events, especially without surgery. Over 15 years, nearly one hundred cases were identified, with approximately half of patients dying during hospitalization. Surgical management significantly improved survival, underscoring the need for early recognition, rapid stabilization, and timely intervention.