Effect of microvascular reperfusion on prognosis and left ventricular function in anterior wall myocardial infarction treated with primary angioplasty

Background Myocardial reperfusion in acute myocardial infarction may fail despite successful recanalization of the infarct-related artery. The purpose of this study was to assess the impact of myocardial reperfusion on clinical outcome and left ventricular (LV) function. Methods The clinical significance of myocardial blush grade (MBG)–angiographic marker of myocardial reperfusion, in 104 patients (age 62 ± 13 years) with first anterior myocardial infarction, successfully (TIMI 3) treated with primary angioplasty was analysed. Echocardiography was performed at baseline and after 6 months. Mortality and major cardiovascular event (MACE) rates were analysed 30 days and 1 year after acute myocardial infarction. Patients were divided into two groups according to presence (group 1, MBG 2–3, n = 64) or absence of myocardial blush (group 2, MBG 0–1, n = 40). Results One-year mortality was significantly higher in group 2 in comparison to group 1 (22.5% vs 6.25%, HR: 3.6, 95% CI: 1.187–10.9, p = 0.0175). The rate of MACE was significantly lower in patients with MBG 2–3, both after 1 and 12 months (9.4% vs 30%, p = 0.008 and 20.3% vs 60%, p < 0.001, respectively). At baseline, both global and regional contractile function were significantly better in group 1 than in group 2 (ejection fraction (EF) 47.4 ± 8.8% vs 43.3 ± 7.9%, p = 0.04 and wall motion score index (WMSI) 1.64 ± 0.4 vs 1.87 ± 0.3, p = 0.001, respectively). Similarly, at 6 months follow-up, LV function was better in group 1 as compared with group 2 (EF 54.9 ± 14.5% vs 46 ± 13.2%, p = 0.005 and WMSI 1.43 ± 0.4 vs 1.76 ± 0.46, p = 0.001, respectively). Conclusions Impaired microvascular reperfusion in patients with anterior myocardial infarction is associated with poor prognosis and worse early and late left ventricular function.