Prognostic implications of quantitative ST-segment characteristics and T-wave amplitude for cardiovascular mortality in a general population from the Health 2000 Survey

Aims. We determined the gender-specific prognostic importance of quantitative measures of the ST segment and T wave in a community cohort. Methods. Data were collected from 5613 Finnish individuals. Four electrocardiogram (ECG) lead groups were used: anterior, lateral, inferior, and lead V5. ST-segment depression, determined at four points along the ST segment, and T-wave amplitude were treated as continuous variables in Cox regression analyses. Results. During a median follow-up period of 72.4 months, 120 cardiovascular deaths were registered. Among women, lateral lead group as well as lead V5 showed highly significant adjusted hazard ratios at all four ST-depression assessment points. This significance was lost in women >= 55 years when those with ECG-based criteria of left ventricular hypertrophy (LVH) were excluded. Results for ST-segment depression were not significant among men. As those with LVH were excluded, men >= 55 years showed borderline significance. T-wave amplitude did not reach significance among men, while lateral leads and lead V5 bore prognostic information among women. Conclusion. Quantitative ST-segment depression, regardless of the measurement point, allows prediction of cardiovascular death in women within a general population. However, the effect disappears as those with LVH are excluded. This observation highlights the need for consideration of LVH when depressed ST segments are clinically observed.