OBJECTIVES
The aim of this study was to evaluate the long-term impact of coronary artery calcification (CAC) on outcomes at 10-year follow-up after percutaneous coronary intervention and the respective performance of different polymer coating strategies of new-generation drug-eluting stents (DES) currently in use.

BACKGROUND
Data concerning the efficacy of different polymer coating strategies of new-generation DES in the specific subset of patients with moderate to severe CAC are scant.

METHODS
This is a pooled analysis of individual patient data of coronary lesions randomized to treatment with polymer-free sirolimus-eluting DES (PF-DES), biodegradable-polymer sirolimus-eluting DES (BP-DES) or permanent-polymer zotarolimus- or everolimus-eluting DES (PP-DES) in the setting of the ISAR-TEST 4 and 5 trials according to the presence of moderate or severe versus no or mild CAC. Endpoints of this analysis were the incidence of all-cause mortality, myocardial infarction (MI), target-lesion revascularization (TLR) and definite or probable stent-thrombosis (ST) according to coronary calcification grade (moderate or severe versus no or mild) and polymer strategy (polymer-free versus biodegradable- versus permanent-polymer) at 10-year follow-up.

RESULTS
A total of 4,953 patients with 6,924 lesions were included. Moderate or severe CAC was present in 1,672 patients (33.8%). Patients with moderate or severe CAC were significantly older (69.2±10.7 vs. 66.4±11.0; p<0.001), displayed a worse clinical risk profile with higher rates of diabetes (33.7% vs. 26.4%; p<0.001), arterial hypertension (71.5% vs. 65.4%; p<0.001), prior coronary artery bypass grafting (13.2% vs. 8.0%; p<0.001) and three-vessel disease (68.8% vs. 52.8%; p<0.001) compared to those with no or mild CAC. At 10-year follow-up, rates of all-cause mortality (42.9% vs. 29.6%; p<0.001, {Figure 1A}) as well as TLR (25.4% vs. 18.5%; p<0.001) were significantly higher in patients with moderate or severe CAC compared to those with no or mild CAC. Moreover, rates of MI (7.6% vs. 6.0%; p=0.008) and ST (2.4% vs. 1.5%; p=0.01) were significantly higher in patients with moderate or severe CAC compared to those with no or mild CAC. Interestingly, clinical event rates at 10-year follow-up were comparable between patients treated with polymer-free, biodegradable- or permanent-polymer new-generation DES (Figure 1B).

CONCLUSIONS
At 10 years, percutaneous coronary intervention of target lesions with moderate or severe CAC was associated with a significant higher rate of adverse outcomes at 10 years. These detrimental effects do not seem to be impacted by whether new-generation DES are polymer-free or polymer is of biodegradable or permanent nature.