Distortion of the QRS in elderly patients with myocardial infarction

Distortion of the terminal portion of the QRS in the initial electrocardiogram (ECG) is a strong predictor of adverse outcome in myocardial infarction. Our purpose is to assess the relationship of distortion of QRS and other ECG characteristics with older age.

We analysed 634 consecutive patients (age 62.6 +/- 13.7, 77% male) admitted in the first 12 hours of ST-elevation myocardial infarction. Two groups of age were defined: < 75 years-old and >or= 75 years-old. Additionally, we defined two ECG groups according to the presence of ST segment elevation with distortion of the terminal portion of the QRS in two or more adjacent leads (QRS+) or the absence of this pattern (QRS-). Older people had more often QRS+ (30% vs. 20%, p = 0.023). The older group with QRS+ had an in-hospital mortality of 18%, vs. 7% with QRS- (p = 0.04), and an incidence of major adverse events of 40% vs. 14% (p = 0.002). In the multivariate analysis, age >or= 75 years was an independent predictor of distortion of the QRS (odds ratio 2.1, 1.2-4.9, p = 0.016).

The distortion of the terminal portion of the QRS in myocardial infarction is more frequent in elderly people, and is significantly related to adverse prognosis. This ECG finding can be helpful to promptly stratify the risk in elderly patients.