Gender-related differences in electrocardiographic parameters and their association with cardiac events in patients after myocardial infarction.

There are limited data regarding gender-related differences in electrocardiographic (ECG) presentation in patients after myocardial infarction (MI) and the prognostic value of ECG variables in women. A series of ECG parameters were analyzed in 838 patients (216 women, 622 men) using standard electrocardiography performed 5 to 7 days after first MI, and their associations with gender and risk for cardiac events, defined as cardiac death, nonfatal MI, or unstable angina, were evaluated. Heart rate was faster and QTc duration was longer, whereas QRS duration was shorter in women compared with men. Women had more lateral ST depressions and more T-wave inversions in the anterior and lateral regions. During mean 2-year follow-up, there were 138 events in men and 65 in women; women had a 38% greater risk for recurrent events (adjusted hazard ratio [HR] 1.38, p = 0.031). In multivariate Cox regression analysis, ST-segment elevation in leads V(1) to V(4) on the fifth to seventh day after MI was associated with increased risk for recurrent events in women (adjusted HR 2.16, p = 0.003) but not in men (adjusted HR = 0.81, p = 0.32). ST depressions in leads V(5), V(6), I, or aVL (adjusted HR 1.70, p = 0.006) in men but not in women (adjusted HR 0.98, p = 0.93) were identified as a risk factor for recurrent events. In conclusion, there are gender-related differences in ECG presentation and the prognostic significance of ECG findings after MI. ST-segment elevation in anterior leads is a significant predictor of events in women, whereas ST depression in lateral leads is a significant predictor in men.