Outcome and Predictors of Stent Thrombosis in the First Romanian Registry of Drug Eluting Stent (RODESINO EXTENSION).

BACKGROUND

Stent thrombosis (ST) is a rare, but extremely severe complication of PCI. Outside clinical trials, data are limited regarding the risks and the impact of this phenomenon.

AIMS

To assess prevalence, predictors, and clinical outcome of ST after implantation of drug eluting stents (DES) compared with bare metal stents (BMS), in a large case-control study in a real world scenario, as well as the relation between ST and duration of combined antiplatelet treatment.

METHODS

In a case-control registry we included 475 patients who received at least 1 DES (sirolimus, zotarolimus, everolimus, paclitaxel), compared with a group of 475 patients who received at least 1 BMS. We used 1.22 DES/patient vs. 1.26 BMS/patient (p=ns), treating 1.02 DES/lesion vs. 1.05 BMS/lesion (p=ns). Main outcome was ST defined by the Academic Research Consortium (ARC) as definite (acute, sub-acute, late), probable, and possible.

RESULTS

At 15 months we found 0.8% (4) patients in the DES group vs. 1.1% (5) patients in the BMS group with definite ST (ns); 0.4% (2) patients from each group had acute ST, while 0.4% (2) vs. 0.7% (3) patients had sub-acute ST (both comparisons were ns). None of the patients from the DES group died, whereas two patients with definite ST from the BMS group died, with a case fatality rate of 40% (2/5). 0.2% (1) patient from each group had probable ST (ns) and 0.6% (3) vs. 0.4% (2) patients had possible ST (ns). Independent predictors of stent thrombosis in merged groups were antiplatelet therapy discontinuation (HR 3.8; 95%CI 1.9-7.6; p<0.01), diabetes (HR 2.15; 95%CI 1.4-5.1; p<0.01), a lower left ventricular ejection fraction (EF) (HR 1.1; 95%CI 1.0-1.9; p<0.01 for each 10% decrease), and LAD lesions (HR 1.0; 95%CI, 0.93-1.9; P<0.01).

CONCLUSIONS

ST is a rare complication (0.95%), similar after DES or BMS implantation. Premature discontinuation of antiplatelet therapy, followed by diabetes and a lower LVEF, are the independent predictors of ST.