ANALYSIS OF THE EKG QT INTERVAL DISPERSION ON REST AND DURING EFFORT TESTING AS A PREDICTOR OF CARDIAC DEATH IN PATIENTS WITH HEART FAILURE.
Aims: QT interval dispersion can be considered as a predictor of cardiac death in patients with heart failure. We evaluate the impact on cardiovascular death of that parameter evaluated during effort testing.
Material and method: We evaluate within one year, 100 patients with heart failure, ischemic(85%), and non ischemic etiology(15%),on admission through rest and effort testing on cicloergometer, echocardiography, and late ventricular potentials. We use multivariate statistic analysis. The rate of hospitalization within one year was 80% and cardiac mortality in the study group was 10%. The coefficient of QT interval dispersion variation during effort steps, has a value of more than 30miliseconds(p<0,001) in patients with cardiac caused death, and his association with low left ventricular ejection fraction (LVFF<35%), (p<0,02), and restrictive left ventricular filling pattern (E/E’>14),(p<0,03) is a stong predictor for cardiac death.
Conclusion: QT interval dispersion analysis at rest and during effort testing in conjunction with left ventricular systolic and diastolic parameters, can be an important predictor of cardiac death in patients with heart failure.