Long-term prognostic significance of isolated minor electrocardiographic T-wave abnormalities in middle-aged men free of clinical cardiovascular disease (The Multiple Risk Factor Intervention Trial [MRFIT])

Wake Forest University, Winston-Salem, North Carolina, United States
The American Journal of Cardiology (Impact Factor: 3.43). 01/2003; 90(12):1391-5. DOI: 10.1016/S0002-9149(02)02881-3
Source: PubMed

ABSTRACT The presence or new onset of isolated minor T-wave abnormalities (Minnesota Code 5.3 or 5.4) associated with a greater spatial T-axis deviation was shown to be independently predictive of long-term (18.5 years) cardiovascular disease and coronary heart disease mortality. This was tested in a cohort of >11,000 middle-aged men who were free of clinical coronary heart disease in the Multiple Risk Factor Interventional Trial.

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    • "The spatial QRS-T angle and spatial T amplitude do not differentiate between recent (5-10 days) and old (>6 months) MI, but distinguish them from healthy controls (Dilaveris et al. 2001). Minor T-wave abnormalities (Minnesota Code 5.3 or 5.4) have independent long-term (6 years and 18.5 years) prognostic value for CHD and cardiovascular mortality in a cohort of men at high risk but free of CHD at entry (Prineas et al. 2002). Spatial T-axis deviation has independent prognostic value, in a cohort of elderly (•65 years) men and women free of CHD at entry, with regard to CHD death (adjusted hazard ratio 2.0), incident CHD (adjusted hazard ratio 1.6), and all-cause mortality (adjusted hazard ratio 1.5). "
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    ABSTRACT: Clinicians are often confronted with the incidental finding of isolated minor, non-specific repolarization changes on the electrocardiogram (ECG) in hypertensive patients. The aim of this study was to investigate the prognostic significance of such changes. Prospective, observational study. A total of 1970 hypertensive patients without prevalent cardiovascular disease were followed for up to 9.1 years (mean 4.7 years). Patients with ECG abnormalities including ischaemia, previous infarction, bundle branch block, atrial fibrillation and ventricular pre-excitation were excluded. Patients were divided into three groups: normal left ventricular (LV) repolarization (n = 1355); minor repolarization changes (n = 504); and typical LV strain (n = 111). During follow-up, 78 patients developed new-onset ischaemic heart disease. The event rates were 0.50, 1.28 and 3.08 per 100 patient-years in the groups with normal repolarization, minor changes, and typical LV strain, respectively (P < 0.001). After adjustment for the effect of age, sex, diabetes, serum cholesterol, smoking, LV hypertrophy and 24-h pulse pressure, the risk for developing coronary events was higher in patients with minor repolarization changes (hazard ratio 2.07, 95% confidence interval 1.23-3.47; P < 0.01) or LV strain (hazard ratio 4.00, 95% confidence interval 2.09-7.65; P < 0.001) than in patients with normal repolarization (reference category). Population-attributable risks were 21 and 14%, respectively. Minor ST-T changes also retained an adverse prognostic value among patients without LV hypertrophy (hazard ratio 1.90, 95% confidence interval 1.08-3.33; P = 0.026). We have identified minor, non-specific LV repolarization changes as a novel, independent risk factor for ischaemic heart disease in patients with uncomplicated hypertension.
    Journal of Hypertension 02/2004; 22(2):407-14. DOI:10.1097/00004872-200402000-00027 · 4.22 Impact Factor
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