Electrocardiographic strain pattern and prediction of cardiovascular morbidity and mortality in hypertensive patients

The ECG strain pattern of lateral ST depression and T-wave inversion is a marker for left ventricular hypertrophy (LVH) and adverse prognosis in population studies. However, whether ECG strain is an independent predictor of cardiovascular ( CV) morbidity and mortality in the setting of aggressive antihypertensive therapy is unclear. ECGs were examined at study baseline in 8854 hypertensive patients with ECG LVH who were treated in a blinded manner with atenolol- or losartan-based regimens. Strain was defined by the presence of a downsloping convex ST segment with an inverted asymmetrical T wave opposite to the QRS axis in leads V-5 and/or V-6 and was present in 971 patients (11.0%). The Losartan Intervention For Endpoint reduction in hypertension ( LIFE) study composite end point of CV death or nonfatal myocardial infarction or stroke occurred in 1035 patients (11.7%). In Cox analyses adjusting only for treatment effect, ECG strain was a significant predictor of CV death ( hazard ratio [HR] 2.26, 95% confidence interval [CI] 1.78 to 2.86), fatal/nonfatal myocardial infarction ( HR 2.16, 95% CI 1.67 to 2.80), fatal/nonfatal stroke ( HR 1.76, 95% CI 1.39 to 2.21), and the composite CV end point ( HR 1.99, 95% CI 1.70 to 2.33). After further adjusting for standard CV risk factors, baseline blood pressure, and severity of ECG LVH, ECG strain remained a significant predictor of CV mortality ( HR 1.53, 95% CI 1.18 to 2.00), myocardial infarction ( HR 1.55, 95% CI 1.16 to 2.06), and the composite CV end point ( HR 1.33, 95% CI 1.11 to 1.59). Thus, ECG strain is a marker of increased CV risk in hypertensive patients in the setting of aggressive blood pressure lowering, independent of baseline severity of ECG LVH.