The effect of smoking on myocardial performance index in middle-aged males after first acute myocardial infarction.

BACKGROUND: Cigarette smoking is associated with increased rates of coronary artery disease and acute myocardial infarction (MI). Paradoxically, smokers had lower mortality after MI. The purpose of this study was to evaluate the effect of chronic smoking on myocardial performance index (MPI) in middle-aged men after an acute MI.

MATERIAL AND METHODS: A total of 429 patients (325 smokers vs. 104 nonsmokers) presenting with acute ST elevation MI were enrolled in this study. Thrombolysis in myocardial infarction (TIMI) flow of the infarct related artery was measured before and after the primary percutaneous coronary intervention (PCI), and Gensini score was also calculated. Conventional echocardiography and tissue Doppler echocardiography (TDI) were performed within 48-72 hours after onset of chest pain. Peak early (Em) and late (Am) diastolic velocities, peak systolic (Sm) mitral annular velocities and time intervals were recorded with TDI. The MPI, ratio of Em/Am, and E/Em were calculated.

RESULTS: Baseline demographic and angiographic characteristics such as Gensini score, pre and, post PCI TIMI flow were similar in 2 groups. In contrast, LV MPI was preserved among smokers (0.59 ± 0.15 vs. 0.66 ± 0.14, P = 0.01), and Em/Am values were also higher in smokers (0.84 ± 0.28 vs. 0.75 ± 0.31, P = 0.01). Independent predictors of impaired MPI (≥0.60) were determined as nonsmoking status (odds ratio 2.940, 95% CI 0.98-5.83, P = 0.05), left anterior descending artery stenosis (odds ratio 3.196, 95% CI 1.73-5.91 P = 0.001), and, age (odds ratio 1.12, 95% CI 1.03-1.22, P = 0.01).

CONCLUSIONS: Despite similar demographic and angiographic characteristics, smoker males had a paradoxically better MPI after acute MI.