Characteristics and prognosis of patients with angiographic stent thrombosis: comparison between drug-eluting and bare-metal stents.

INTRODUCTION

Conflicting data exist on the risk of stent thrombosis with drug-eluting stents (DES) versus bare-metal stents (BMS). Little is known about the potential different characteristics and outcomes of DES versus BMS thrombosis.

OBJECTIVE

To compare the characteristics, timing and outcomes of patients with angiographic stent thrombosis according to type of stent implanted.

METHODS

The population comprised consecutive patients who underwent BMS or DES implantation (January 2003-April 2007) at Pitié-Salpêtrière Hospital. Data from patients with and without a stent thrombosis were compared to identify predictors of thrombosis. Timing of thrombosis (acute,<24 hours; subacute,<30 days; late,>30 days; very late,>1 year), clinical, angiographic and procedural characteristics, and outcomes were compared between patients with a BMS or DES thrombosis.

RESULTS

A total of 3579 patients received a BMS (2815 lesions, 2318 patients) or a DES (1536 lesions, 1261 patients). Documented angiographic stent thrombosis occurred in 52 (1.4%) patients, 16 (1.3%) with a DES and 36 (1.6%) with a BMS. Rates of acute (0.1% versus 0.2%), subacute (1% versus 0.7%), late (both 0.2%) and very late (both 0.2%) thrombosis were similar in patients with BMS and DES thrombosis. Factors predictive of stent thrombosis were similar, including left ventricular failure (P<0.0001), initial percutaneous coronary intervention (PCI) for acute myocardial infarction (P<0.0001), multivessel PCI (P<0.0001), and balloon dilatation before stenting (P<0.04). Eleven (21%) cases of BMS (n=8, 22%) or DES (n=3, 19%) thrombosis arose soon after stopping antiplatelet therapy. Thirteen of 52 (25%) patients died a few hours after the event. Twenty-seven (52%) major adverse cardiac events occurred at 18 months, 7 in patients with a DES and 20 in those with a BMS (44% versus 55%, P=NS). These included 16 deaths (31%), 7 repeat PCIs and 4 myocardial infarctions. There were no independent predictive factors of death after stent thrombosis.

CONCLUSIONS

BMS and DES thrombosis are similar in terms of timing of thrombosis, characteristics and outcomes, and share the same risk of late thrombosis after interruption of antiplatelet therapy.