Anticoagulation May Be Safe After Bioprosthetic Aortic Valve Replacement

Anticoagulation may be safe at discharge in patients with clinical indications for anticoagulation and acceptable bleeding risks undergoing bioprosthetic aortic valve replacement (AVR), according to a study published in the Journal of the American College of Cardiology.

The investigators studied a total of 4832 patients undergoing bioprosthetic AVR (transcatheter AVR [TAVR], n=3889; surgical AVR [SAVR], n=943) in the pooled cohort of Placement of Aortic Transcatheter Valves (PARTNER2) randomized trials and nonrandomized registries.

Intermediate-risk patients with severe symptomatic aortic stenosis were randomly assigned to TAVR with Sapien-XT or SAVR in PARTNER 2A. In PARTNER 2B, patients with inoperable severe symptomatic aortic stenosis were randomly assigned to Sapien-XT or Edwards-Sapien valves. Patients enrolled in the study had severe symptomatic aortic stenosis of native trileaflet aortic valve or symptomatic degeneration of surgical aortic bioprostheses.

The study was mainly aimed at assessing the effect of anticoagulation after bioprosthetic AVR on the valve hemodynamics and clinical outcomes. Valve hemodynamics were evaluated using the mean trans-valvular gradients and aortic valve areas. Death, myocardial infarction, rehospitalization, stroke, transient ischemic attack, bleeding, aortic valve reintervention, and prosthetic valve dysfunction (stenosis or regurgitation) were the clinical end points that were included in the analysis.

Anticoagulation after discharge had no significant effect on aortic valve hemodynamics in the short term. Except for fewer strokes in surgical patients discharged on anticoagulation, anticoagulation after bioprosthetic AVR did not affect clinical outcomes. The investigators stated that the study demonstrated excellent durability of both transcatheter and surgical bioprostheses up to 1 year. The increase in mean gradient >10 mm Hg from 30 days to 1 year was significantly higher in patients discharged without anticoagulation compared with those discharged on anticoagulation.

Results also showed that anticoagulation did not affect the incidence of aortic valve reintervention or prosthetic valve dysfunction. However, the rates of stroke continued to be lower among patients on anticoagulation after SAVR but not after TAVR.

There are some important limitations to the current study. According to the investigators, 5% of the patients were discharged on oral anticoagulants after bioprosthetic AVR, but the effect of these oral anticoagulants was not documented. Also, post-AVR computed tomography imaging was not performed to evaluate the effect of anticoagulation on subclinical leaflet thrombosis. Furthermore, a small portion of patients treated by TAVR or SAVR were discharged on anticoagulation only; hence, it was difficult to assess the true effect.

The early anticoagulation after bioprosthetic AVR had no significant effect on valve hemodynamics or value durability and showed no adverse clinical effects. However, the investigators stated that long-term follow-ups are needed to determine the clinically meaningful differences in valve hemodynamics and durability.

Disclosures: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.

Reference 

Chakravarty T, Patel A, Kapadia S, et al. Anticoagulation after surgical or transcatheter bioprosthetic aortic valve replacement.J Am Coll Cardiol. 2019;74(9):1190-1200.