Impact of Coronary Calcification on Clinical Outcomes After Implantation of Newer-Generation Drug-Eluting Stents

BACKGROUND: Percutaneous coronary intervention of calcified lesions was associated with worse outcomes in the era of bare-metal and first-generation drug-eluting stents. Data on percutaneous coronary intervention of calcified lesions with newer-generation drug-eluting stents are scarce. Therefore, we investigated the impact of lesion calcification on clinical outcomes in patients undergoing percutaneous coronary intervention with a bioresorbable-polymer sirolimus-eluting stent or a durable-polymer everolimus-eluting stent. METHODS AND RESULTS: Patients (n=2361) from BIOFLOW II, IV, and V trials were categorized into moderate/severe versus none/mild lesion calcification by a core laboratory. End points were target-lesion failure (TLF) (cardiac death, target-vessel myocardial infarction, or target-lesion revascularization) and probable/definite stent thrombosis at 2 years. The agreement in calcification assessment between the operator and the core laboratory was weak (weighted., 0.23). Patients with moderate/severe calcification (n=303; 16%) had higher TLF (13.5% versus 8.4%; P=0.003) and stent thrombosis rates (2.1% versus 0.2%; P<0.0001), whereas target-lesion revascularization was not different between the groups (5.0% versus 3.9%; P=0.302). After adjustment, calcification did not emerge as an independent predictor of TLF (adjusted hazard ratio [aHR], 1.37; 95% CI, 0.89-2.08; P=0.148) but did for target-vessel myocardial infarction (aHR, 1.66; 95% CI, 1.03-2.68; P= 0.037). TLF rates were similar between bioresorbable-polymer sirolimus-eluting stent and durable-polymer everolimus-eluting stent (12.6% versus 15.4%, P=0.482) in moderate/severe calcification. In none/mild calcification, the bioresorbable-polymer sirolimus-eluting stent showed lower TLF (7.5% versus 10.3%, P=0.045). CONCLUSIONS: With newer-generation drug-eluting stents, moderate/severe lesion calcification was not associated with more TLF after adjustment for the higher risk of patients with coronary calcification, whereas the rate of target-vessel myocardial infarction was higher. The bioresorbable-polymer sirolimus-eluting stent and durable-polymer everolimus-eluting stent were equally effective and safe in calcified lesions.