Significance of left atrial overload by electrocardiogram in the assessment of left ventricular diastolic dysfunction

Background Although assessment of left ventricular (LV) diastolic function (DF) using echocardiography is important, it is not always feasible in the clinical practice. On the other hand, left atrial (LA) overload shown by electrocardiogram (ECG) indicates LA pressure rise and LA dilatation. The purpose of this study is to examine whether LA overload by ECG can be used as an aid for evaluation of LVDF. Methods There were 117 subjects who underwent echocardiography and ECG on the same day. The duration of P-wave (P-duration) in lead II, the amplitude and duration of P-wave negative phase in lead V1 were measured by ECG, and terminal force (PTFV1) was calculated. We analyzed the relationships between LVDF grades and LA overload signs. Results P-duration showed a good correlation with LA volume index (LAVi) (r = 0.673, P < 0.0001) and PTFV1 showed reasonable correlations with both LAVi and average E/e ' (both, r = 0.575, P < 0.0001). Both P-duration and PTFV1 showed significant differences among the LVDF classes (P < 0.0001). Among the ECG indices, P-duration >=\110 ms was the most powerful to judge the presence of LV diastolic dysfunction with 86% of sensitivity and specificity. Conclusions P-duration >= 110 ms is useful to suggest the presence of LV diastolic dysfunction. Conventional ECG criteria (P-duration >= 120 ms and PTFV1 >= 0.04 mm center dot s) are highly specific and suggest the presence of LV diastolic dysfunction with LA pressure rise. Echocardiography and ECG should be used in a complementary way when LVDF grades are indeterminate.