Detection of restenosis after coronary angioplasty for single-vessel disease: how reliable are exercise electrocardiography and scintigraphy in asymptomatic patients?

The diagnostic value of exercise electrocardiography and thallium myocardial scintigraphy for the detection of restenosis was assessed in 111 patients undergoing control angiography 6 months after successful coronary angioplasty. All patients were free of symptoms at the time of the study. A diameter reduction of 70% or more at the site of angioplasty was considered restenosis. The sensitivity of exercise electrocardiography is low (64%). Exercise ECG and scintigraphy are highly specific (respectively 90% and 93%). The predictive value of a positive ECG or thallium scintigraphy is poor (respectively 53% and 63%). The value of a negative scintigraphic result is slightly better than the predictive value of a negative ECG (98% vs 95%; NS). A negative exercise scintigraphy almost excludes severe restenosis. These non-invasive tests seem suitable for the detection of asymptomatic restenosis.