Background: Drug-eluting stents (DES) represent a significant improvement in the treatment of coronary artery disease as they decrease restenosis rates by approximately 50% compared with bare-metal stents. In-stent restenosis (ISR) is perceived to be a benign phenomenon because it is a gradual process and may lead to angina pectoris. With bare-metal stents, ISR has been associated with myocardial infarction in approximately 10% to 15% of cases. Comparable data with DES are lacking.
Methods: From April 2003 to December 2005, 42 out of 889 patients (4.7%) with DES ISR were identified at our institution. We excluded 3 orthotopic heart transplant patients who had ISR. Therefore, the final analysis included 39 patients.
Results: The mean age was 66 +/- 10 years, 77% were male, and 33% were diabetic. A mean of 1.8 +/- 0.9 stents were implanted with a total stent length of 39 +/- 24 mm. The mean time from percutaneous coronary intervention to detection of ISR was 396 +/- 290 days. At a mean from follow up of 35 +/- 10 months, 8% were asymptomatic, 77% presented with angina pectoris, 5% with unstable angina, and 10% with non-ST-segment elevation myocardial infarction.
Conclusions: In the DES era, although most patients with ISR have stable symptoms, myocardial infarction occurred in 10%, suggesting that ISR is not a benign clinical entity. DES with improved designs or drug elution systems that further decrease the incidence of ISR are needed.