A New Predictor of Restenosis After Successful Percutaneous Transluminal Coronary Angioplasty in Patients With Multivessel Coronary Artery Disease

Abstract

With the goal of improving prediction of restenosis after percutaneous transluminal coronary angioplasty (PTCA) for multivessel coronary artery disease (CAD), we evaluated the usefulness of serial exercise treadmill tests. We previously reported that an increase in the ΔST/Δheart rate (HR) index at follow-up over the value obtained several days after PTCA was useful for detecting restenosis following PTCA for 1-vessel CAD. In that report, comparison of the ΔST/ΔHR index was made based on measurements from the lead disclosing the greatest ST displacement before PTCA. This method was not applicable to patients with multivessel CAD. Seventy-eight patients with multivessel CAD before and several days after PTCA and just before follow-up performed exercise treadmill tests. Simple HR-adjusted indexes of ST-segment depression during exercise (ΔST/ΔHR index) and the sum of the ΔST/ΔHR index in leads II, III, aVF, V4, V5, and V6 (ΣΔST/ΔHR index) were determined. We compared the predictive power of an increase in ΣΔST/ΔHR index at follow-up with that of a positive exercise treadmill test and a positive thallium scintigram for restenosis. At follow-up, 37 of the 78 patients showed restenosis. The ΣΔST/ΔHR index had increased in 30 of these 37 patients (81%), and in 12 of the 41 patients (29%) without restenosis. An increase in ΣΔST/ΔHR index had a significantly higher sensitivity than the other methods and a significantly higher specificity than a positive exercise treadmill test.