Effect of restenosis after an earlier angioplasty at another coronary site on the frequency of restenosis after a subsequent coronary angioplasty

Restenosis remains a major problem in patients undergoing percutaneous transluminal coronary angioplasty. A number of constitutional factors such as male gender,¹ diabetes mellitus,^1,2 cigarette smoking² and unstable angina,^1,2 as well as local arterial factors including initial total occlusion,³ severe residual stenosis⁴ and elevated translesional final gradient¹ have been associated with an increased frequency of restenosis. However, these factors are not necessarily causal, and the exact stimulus and mechanism of the cellular response resulting in restenosis remain unknown. In addition, the relative importance of constitutional and local arterial factors on the development of restenosis is unclear. Patients are often referred for angioplasty of atherosclerotic coronary narrowings having previously undergone angioplasty of a different site in the coronary circulation. However, it is not known whether patients in whom restenosis developed after the earlier angioplasty are at increased risk of developing restenosis following angioplasty of a new lesion. The answer to this question could shed some light on the relative contribution of constitutional versus local arterial factors on restenosis. Accordingly, to determine whether restenosis occurs more frequently among patients with a history of restenosis, we performed a retrospective databank analysis of patients at our institution who had undergone angioplasty and identified a select group of patients who had had a successful angioplasty and who subsequently had another angiopla'ty performed at a different coronary site.