Primary percutaneous coronary intervention lowers the incidence of ischemic mitral regurgitation in patients with acute ST-elevated myocardial infarction.

BACKGROUND: The impact of primary percutaneous coronary intervention (PCI) for acute ST-elevated myocardial infarction (STEMI) on the incidence of ischemic mitral regurgitation (IMR) is unclear.

METHODS AND RESULTS: Between January 2000 and December 2004, 318 patients presenting with first acute STEMI were enrolled in this study. Two hundred and twelve (66.67%) patients received PCI (PCI group), and 106 age- and Killip class-matched patients received medical management (non-PCI group). The median duration of follow up was 40.46 months. Compared to the non-PCI group, the PCI group had 14.6% (9.9% vs 24.5%) fewer patients with moderate or severe IMR (P<0.001). Univariate analysis demonstrated IMR was significantly associated with advanced age, higher Killip score, and posterior myocardial infarction (MI). Moreover, IMR was strongly associated with a lower left ventricular (LV) ejection fraction, larger left atrial dimension (LAd), and a larger LV end-systolic and LV end-diastolic volumes (LVEDV) (all P<0.01). Multivariate analysis revealed the odds of IMR in the PCI group was 0.208 times those of the non-PCI group (P<0.001). Additionally, moderate or severe IMR was independently correlated with advanced age, inferior MI, Killip class ≥3, larger LAd, and larger LVEDV (all P<0.05). Furthermore, long-term survival time was longer in the PCI group without IMR than in the non-PCI group with IMR (all P<0.01).

CONCLUSIONS: PCI for first acute STEMI was associated with lower incidence of IMR. Advanced age, inferior MI, Killip class ≥3, larger LAd and LVEDV were risk factors associated with IMR development.