Very Late Thrombosis of a Sirolimus-Eluting Stent after 57 Months

From the *University of Miami Miller School of Medicine, and Charles E. Schmidt College of Science, Florida Atlantic University, Boca Raton, Florida, and §Nova Southeastern College of Medicine, Ft. Lauderdale, Florida. The authors report no conflicts of interest regarding the content herein. Manuscript submitted May 29, 2009, provisional acceptance given June 24, 2009, final version accepted July 7, 2009. Address for correspondence: Anil Paturi, MD, Internal Medicine Residency Program, JFK Medical Center, 4 South, 5301 S. Congress, Atlantis, FL 33462. E-mail: apaturi@med.miami.edu

_______________________________________________

J INVASIVE CARDIOL 2009;21:E252-E253 Case Description. A 77-year-old nonsmoking female with a previous medical history of hypertension, diabetes, and coronary artery disease underwent placement of a sirolimus-eluting stent in the left anterior descending artery (LAD) in August 2004 following bare-metal stent (BMS) placement in the circumflex artery in February 2003. She was free of coronary symptoms until she was hospitalized with epigastric pain and chest discomfort in April 2009. Aspirin and clopidogrel were stopped due to suspected upper gastrointestinal (GI) bleeding, though neither esophagastroduodenoscopy nor barium swallow were performed and her hemoglobin was stable. She was discharged home on esomeprazole, then presented 10 days later with persistent and worsening chest pain and new anterior ST-elevation (May 2009). A thrombotic occlusion at the stent site in the LAD (Figure 1) was treated with thrombectomy and successfully revascularized with superimposition of an everolimus-eluting stent (Figure 2). Another drug-eluting stent (DES) was chosen to reduce the chance of restenosis and because she was compliant with dual-antiplatelet therapy until it was discontinued by a physician. Moderate in-stent restenosis was found at the BMS site in the circumflex artery (not shown). Discussion. Discontinuation of antiplatelet medications has been strongly associated with DES thrombosis.1 Eisenberg et al identified a cluster of cases occurring within 10 days of the simultaneous discontinuation of aspirin and clopidogrel,2 as in this case. This temporal relationship suggests the possibility of rebound platelet hyperactivation as a mechanism. Late stent thrombosis has been reported up to 5 years after DES implantation.4 It has been suggested that late stent thrombosis occurs steadily at an annual rate of 0.4–0.6% for up to 4 years.5 It is not clear that late stent thrombosis risk diminishes with time. This case and one other just beyond 5 years of stent placement4 suggest that late stent thrombosis risk may continue longer, perhaps indefinitely. When faced with actual or suspected bleeding, patients should be investigated aggressively to find the cause, in the hopes of permitting the continuation, or reinstitution of antiplatelet therapy as promptly as possible. While proton-pump inhibitors may be effective to treat or prevent GI bleeding, their use may attenuate the benefits of clopidogrel and further risk late stent thrombosis.3 It is important when bleeding is suspected or not life-threatening, that one, and not both, antiplatelet drugs be held.2 Most episodes of very late stent thrombosis tend to occur more frequently when both antiplatelet drugs are stopped as compared to stopping one antiplatelet drug.2

2. Eisenberg MJ, Richard PR, Libersan D, Filion KB. Safety of short-term discontinuation of antiplatelet therapy in patients with drug-eluting stents. Circulation 2009;119:1634–1642.

3. Ho PM, Maddox TM, Wang L. Risk of adverse outcomes associated with concomitant use of clopidogrel and proton pump inhibitors following acute coronary syndrome. JAMA 2009;301:937–944.

4. Layland J, Jellis C, Whitbourn R. Extremely late drug-eluting stent thrombosis: 2037 Days after deployment. Cardiovasc Revasc Med 2009;10:55–57.

5. Wenaweser P, Daemen J, Zwahlen M, et al. Incidence and correlates of drug-eluting stent thrombosis in routine clinical practice. 4-Year results from a large 2-institutional cohort study. J Am Coll Cardiol 2008;52:1134–1140.