Relation between QT duration and mortality in an elderly Japanese population.

The effects of prolonged QTc intervals on mortality were investigated in about 3,500 elderly Japanese patients followed for approximately 8.8 years. Prolonged QTc was found to be a marker for risk for all-cause mortality and mortality from heart disease or from coronary heart disease (CHD) after adjusting for other CHD risk factors. Even in Japanese subjects, who have a lower coronary heart disease rate than that of Caucasians, the careful observation of subjects with a prolonged QTc is believed to be necessary.