How Long Should the Long-Term Outcomes
Be for Drug-Eluting Stent Recipients?

We read with interest the article by Mishkel and colleagues¹ along with the accompanying editorial in the August 2007 issue of the Journal of Invasive Cardiology. The authors compared short-term and 2-year outcomes of drug-eluting stents (DES) among patients with and without chronic kidney disease (CKD), and consistent with many previous studies, found increased inc idence of major adverse cardiovascular events (MACE) in CKD patients.
The study does not help readers with the choice of stent in CKD patients since the authors did not report outcomes of bare-metal stent (BMS) recipients in this study. Prior studies by Halkin et al² in dialysis patients as well as by Zhang et al³ in patients with moderate renal insufficiency have found superiority of DES versus BMS in patients with CKD in the reduction of MACE in 1–2 years. We have previously reported comparative outcomes in patients with BMS (n = 381) versus DES implantation (n = 139) and creatinine 2.0 from 9,598 consecutive patients who underwent PCI with stent placement at our center.⁴ Consistent with the results reported by Mishkel and colleagues, we have found that the type of DES used (sirolimus versus paclitaxel) had a similar effect on MACE. Comparative outcomes between DES and BMS recipients showed that DES placement had a protective effect on MACE (hazard ratio 0.66; p = 0.028), but the benefit decreased with time.
There is a more fundamental question that is vital to our practice: How long should the follow up be to determine the long-term outcomes of DES? Recently, a Food and Drug Administration (FDA) panel concluded that the off-label use of DES (such as in patients with CKD) is associated with increased risks of late stent thrombosis, especially after the first year.⁵ Since the majority of the above studies on CKD patients have not looked beyond 1–2 years of outcomes, they cannot help us estimate the true long-term consequences of DES. Patients with CKD also have a higher-than-average bleeding risk and this may be increased further with the long-term need for thienopyridines (clopidogrel or ticlopidine) for DES recipients. Pending long-term cohort studies or larger randomized clinical trials in patients with CKD, we feel that the choice of stent is less than obvious and should be made after careful evaluation of the bleeding risk of the individual CKD patient versus the restenosis benefit of DES.

Surabhi Madhwal, MD
Medicine Institute, Cleveland Clinic
Cleveland, Ohio

Girish Mood, MD Associate Staff
Department of Cardiovascular Medicine
Cleveland Clinic

Samir Kapadia, MD Director, Intervention Fellowship Program
Department of Cardiovascular Medicine
Cleveland Clinic

Stephen Ellis, MD
Director The Sones Cardiac Catheterization Laboratory Department of Cardiovascular Medicine
Cleveland Clinic

Vidyasagar Kalahasti, MD Staff, Department of Cardiovascular Medicine
Cleveland Clinic