Impact of calcium on procedural and clinical outcomes in lesions treated with bioresorbable vascular scaffolds - A prospective BRS registry study

Background There is limited data on the impact of calcium (Ca) on acute procedural and clinical outcomes in patients with lesions treated with bioresorbable vascular scaffolds (BRS). We sought to evaluate the effect of calcium on procedural and clinical outcomes in a ‘real world’ population. Methods Clinical outcomes were compared between patients with at least 1 moderately or heavily calcified lesion (Ca) and patients with no/mild calcified lesions (non-Ca) enrolled in our institutional BRS registry. Results 455 patients (N) with 548 lesions (L) treated with 735 BRS were studied. Patients in the Ca group (N = 160, L = 200) had more complex (AHA B2/C lesion: 69.0% in Ca vs 14.9% in non-Ca, p < 0.001) and significantly longer lesions (27.80 ± 15.27 vs 19.48 ± 9.92 mm, p < 0.001). Overall device success rate was 99.1% with no significant differences between the groups. Despite more aggressive lesion preparation and postdilation compared to non Ca, acute lumen gain was significantly less in Ca lesions (1.50 ± 0.66 vs 1.62 ± 0.69 mm, p = 0.040) with lower final MLD (2.28 ± 0.41 vs 2.36 ± 0.43, p = 0.046). There were no significant differences in all-cause mortality, total definite scaffold thrombosis (ST), target lesion revascularization and myocardial infarction between the 2 groups. Late ST was more frequent in the Ca group compared to non Ca group (late ST: 2.1 vs 0%, p = 0.02). Conclusions Clinical outcomes after BRS implantation in calcified and non-calcified lesions were similar. A remarkable difference in timing of thrombosis was observed, with an increased rate of late thrombosis in calcified lesions.