Gene polymorphisms in dual antiplatelet therapy and the presence of hypo-attenuated leaflet thickening after transcatheter aortic valve replacement.

The imaging finding of hypo-attenuated leaflet thickening (HALT) on bioprosthesis after transcatheter aortic valve replacement (TAVR) has been reported. The underlying mechanism is not clear, but leaflet thrombosis is speculated to be the cause. Heterogeneous antiplatelet responses may play a role in the process. This is a prospective, single-center pilot study in patients who received successful TAVR from June 2012 to November 2016. HALT on post-procedural multi-detector computed tomography. We thoroughly genotyped 34 SNPs and 8 SNPs that have been reported for clopidogrel and aspirin resistance. A total of 148 patients were enrolled. There were 15 patients demonstrating signs of HALT. Patients with HALT had a higher rate of atrial fibrillation (AF) pre-TAVR (33.3 vs. 7.5%, P = 0.01). We found that rs4244285 G>A polymorphism of the CYP2C19 gene was associated with the risk of HALT in the overdominant model (OR 4.00 [1.15-13.97], P = 0.02 for GA vs. GG+AA) adjusted by sex and the presence of pre-TAVR AF. Antiplatelet drug resistance is a reasonable possibility involved in HALT. Potential directions were suggested in polymorphisms of the CYP2C19 gene.