Factors affecting ST depression during cardiopulmonary exercise testing in patients with mitral stenosis without significant coronary lesions.

Symptom-limited cardiopulmonary exercise testing was performed in 37 patients with mitral stenosis (MS) without significant coronary artery stenosis to evaluate factors affecting ST depression in exercise electrocardiograms. The degree of ST depression was not associated with gender or exercise tolerance. The incidence of significant ST depression was higher in the patients receiving than in those not receiving digitalis (P < 0.05). In addition, the patients with atrial fibrillation and a higher heart rate response were more likely to have a high prevalence of significant ST depression than those with sinus rhythm and a lower response (P < 0.05). We concluded that atrial fibrillation, a higher maximum heart rate, and oral digitalis administration were involved in ST depression during exercise testing in patients with mitral stenosis without coronary heart disease.