Aims: We studied tissue Doppler parameters in patients with atrial fibrillation following acute myocardial infarction, and their relation to P wave durations and P dispersion.
Methods: Echocardiographic examination was performed in 84 consecutive patients with first anterior acute myocardial infarction. In addition to other conventional echocardiographic parameters, the peak systolic (Sm), early diastolic (Em) and late diastolic (Am) velocities were obtained at the lateral corner of the mitral annulus by pulsed wave tissue Doppler. The Em/Am ratio and the ratio of early diastolic mitral inflow velocity to Em (E/Em), which is a marker of diastolic filling pressure, were calculated. Electrocardiogram was recorded from all patients on admission; P wave measurements were also performed.
Results: Atrial fibrillation occurred in 20 (23.8%) of 84 patients. The patients with atrial fibrillation had significant reduction of Em (5.6+/-1.5 vs. 8.7+/-2.7 cm/s, p < 0.001), Em/Am (0.61+/-0.27 vs. 0.84+/-0.23, p = 0.001) and Sm (7.1+/-1.0 vs. 8.3+/-1.9 cm/s, p < 0.001) values compared with those without. The E/Em ratio (14.45+/-4.62 vs. 7.47+/-2.79, p < 0.001), P maximum (102+/-11 vs. 95+/-11 ms, p = 0.02) and P dispersion (35+/-7 vs. 26+/-7 ms, p < 0.001) were significantly higher in patients with atrial fibrillation than in those without. In all patients, P dispersion showed significant correlation with Em (r = -0.33, p = 0.002), Sm (r = -0.40, p < 0.001) and E/Em (r = 0.32, p = 0.003). When E/Em > or = 10 was used as cutpoint, atrial fibrillation could be predicted with a sensitivity of 90%, and a specificity of 84%.
Conclusions: The patients with atrial fibrillation following acute myocardial infarction have reduced systolic and diastolic mitral annular velocities and increased E/Em ratio, P maximum and P dispersion values compared to those without. P dispersion is correlated with systolic and diastolic left ventricular function after acute myocardial infarction. The E/Em ratio appears to be a useful parameter for assessing the risk of atrial fibrillation occurrence after anterior acute myocardial infarction.