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 κ, 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. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifiers: NCT01356888, NCT01939249, NCT02389946.