Clinical data on optimal management of mechanical complications of myocardial infarction are lacking. We retrospectively evaluated the effect of intra-aortic balloon pump (IABP) on 30-day survival in patients with postinfarction ventricular septal rupture (VSR, n = 55) or acute mitral regurgitation (MR, n = 26) who developed either cardiogenic shock (n = 46) or severe hemodynamic instability that did not fulfill the criteria of shock (n = 35).
IABP was inserted in 83% of the patients with shock and 57% of those without shock. Thirty-five (76%) patients with shock and all unstable patients survived until surgical repair, which was performed within a median (interquartile range) of 1 (1 to 2) and 9 (2 to 18) days from the onset of the complication (p < 0.001).
All patients who did not undergo the operation died within 3 days. Although MR presented more acutely, the patients' outcomes were similar to those with VSR.
IABP support reduced 30-day mortality in the patients with shock (61% vs 100%, p = 0.04) but not in the patients without shock (20% vs 27%, p = 0.7). The benefit of IABP support in the shock cohort was driven mainly by reduction of preoperative mortality (11% vs 88%, p < 0.001).
Early progression of cardiogenic shock and unperformed surgery were the only independent predictors of 30-day mortality (hazard ratio 3.4, 95% confidence interval 1.5 to 8 and hazard ratio 5.1, 95% confidence interval 2.2 to 11, respectively; p = 0.004 and p < 0.001, respectively). In conclusion, we suggest that all patients with postinfarction VSR or acute MR with signs of cardiogenic shock should immediately receive IABP as a bridge to emergent surgical repair.
In contrast, hemodynamically unstable patients without shock may be first stabilized by medical therapy, without additional benefit of IABP, before they undergo cardiac surgery.