Painful and silent myocardial ischaemia during exercise testing

The study was designed to clarify the clinical and angiographic attributes of patients with exercise induced silent myocardial ischaemia. The sample consisted of 102 patients who had ischaemic exercise electrograms (greater than or equal to 1 mm ST segment depression) and had a significant angiographic stenosis (greater than 50% diameter stenosis), in at least one of the major coronary arteries. In 61 patients (60%) painful ischaemia was observed during exercise (group A) while in 41 patients (40%) only ST depression (silent ischaemia) occurred (group B). The groups were similar with respect to age, sex, history of diabetes and all angiographic parameters including the Gensini coronary score. A history of prior myocardial infarctions was observed more frequently (p less than 0.01) in patients with silent ischaemia (group B). Prior myocardial infarction may be a factor causing silent myocardial ischaemia.