Coronary artery disease progression late after successful stent implantation

Abstract

Objectives: This study sought to define the importance of 5-year coronary artery disease (CAD) progression after successful stenting.

Background: Safety concerns regarding first-generation drug-eluting stents mandate 5-year follow-up studies. However, only limited data exist on the long-term importance of CAD progression relative to late stent-related problems.

Methods: This study followed for 5 years, 428 consecutive patients randomized to drug-eluting versus bare-metal stents with successful stenting documented by freedom from symptoms/events and no ischemic perfusion defects (PDs) after 6 months. Rest/stress scintigraphic scans were repeated after 60 months. Late events and new PDs in areas remote from stented vessels indicated CAD progression.

Results: During follow-up, 110 of 428 (25.7%) patients had 150 clinical events: 43 patients (10%) died, 36 (8.4%) suffered a myocardial infarction, and 71 (16.6%) needed repeat revascularization. Event rates were lower in remote versus target-vessel areas (9.8% vs. 14.3%, p = 0.019). Remote myocardial infarction and repeat revascularization accounted for 46 of 124 (37.1%) nonfatal events and were similar for both stent types. Five-year scintigraphic studies in patients without follow-up events showed 23.3% new PDs, 71% of which were asymptomatic. Remote defects accounted for 37.5% PDs and were similar for both stent types.

Conclusions: Even 5 years after stenting, target-vessel events and/or new PDs remained more frequent than CAD progression assessed by remote events and/or new PDs. Still, remote events accounted for almost 40% of all events with a similar rate of additional new PDs, often silent, and independent of stent type. This documents the importance of CAD progression and stresses the need to differentiate remote from target-vessel events/PDs in long-term stent safety studies. (Basel Stent Kosten-Effektivitäts Trial [BASKET]; ISRCTN75663024).