Following PTCA exercise tolerance is only moderately correlated with cinevideo-densitometric measurement of restenosis.

There is a pressing need for a non-invasive marker of restenosis following percutaneous transluminal coronary angioplasty. Computerised measurement of restenosis has not been used in conjunction with exercise test variables reflecting maximum exercise capacity. Thus we investigated thirty consecutive patients undergoing repeat coronary angiography for restenosis who had a satisfactory symptom limited exercise test. Exercise test variables namely ST segment depression, maximum exercise tolerance and rate/pressure product were correlated with the percentage stenosis measured by videodensitometry. Maximum exercise tolerance expressed in metabolic equivalents was correlated with restenosis severity (correlation coefficient -0.52, p = 0.003) as was maximum duration of exercise (correlation coefficient -0.46, p = 0.01). Maximum ST segment depression on exertion was not correlated with the degree of restenosis. In assessing patients after angioplasty exercise tolerance is related to the severity of restenosis. However the degree of variation within this relationship is such that it cannot be used confidently in the clinical setting to predict restenosis.