False positive ECG and coronary heart disease.

ABSTRACT

In 1983, we carried out a cross-sectional, rural community based study and highlighted an abysmally low prevalence of probable coronary heart disease in resting electrocardiogram. A seven year follow-up (1983-1990) of 179 suspects showed no morbidity or mortality from coronary heart disease. Eighty one out of 98 suspects tested negative on a symptom limited maximal exercise test. Though seventeen suspects had an asymptomatic exercise-induced ST depression (> 1.0 mm) their haemodynamic response to exercise and effort tolerance was excellent. Of the twelve subjects who took a repeat exercise test six months later, eleven failed to show ST depression on exercise. We attribute the false positivity of exercise test and its poor reproducibility to labile electrocardiographic changes unmasked by exercise.