Outcomes of Patients with a Mechanical Heart Valve and Poor Anticoagulation Control on Warfarin

Isabelle Johansson; Alexander P Benz; Tanya Kovalova; Kumar Balasubramanian; Bianca Fukakusa; Matthew J Lynn; Nikhil Nair; Omaike Sikder; Kashyap Patel; Sai Gayathri; Marlene Robinson; Colin Hardy; Jessica Tyrwhitt; Sam Schulman; John W Eikelboom; Stuart J Connolly

doi:10.1055/s-0043-1777827

Outcomes of Patients with a Mechanical Heart Valve and Poor Anticoagulation Control on Warfarin

Thromb Haemost. 2023 Dec 29. doi: 10.1055/s-0043-1777827. Online ahead of print.

Authors

Isabelle Johansson^{1

2}, Alexander P Benz^{1

3}, Tanya Kovalova¹, Kumar Balasubramanian¹, Bianca Fukakusa⁴, Matthew J Lynn⁵, Nikhil Nair⁶, Omaike Sikder⁷, Kashyap Patel⁸, Sai Gayathri⁹, Marlene Robinson¹⁰, Colin Hardy¹, Jessica Tyrwhitt¹, Sam Schulman¹⁰, John W Eikelboom¹, Stuart J Connolly¹

Affiliations

¹ Population Health Research Institute, Hamilton Health Sciences, McMaster University, Ontario, Canada.
² Division of Cardiology, Department of Medicine K2, Karolinska University Hospital Solna, Karolinska Institutet, Stockholm, Sweden.
³ Department of Cardiology, University Medical Center Mainz, Johannes Gutenberg-University, Mainz, Germany.
⁴ Division of Cardiology, Department of Pediatrics, The University of British Columbia, Vancouver, Canada.
⁵ Department of Medicine, University of British Columbia, Vancouver, Canada.
⁶ Division of Medicine, Michael G. DeGroote School of Medicine, McMaster University, Hamilton, Canada.
⁷ Division of Medicine, School of Nursing, McMaster University, Hamilton, Canada.
⁸ Department of Medicine, University of Ottawa, Ottawa, Ontario, Canada.
⁹ Department of Medicine, Faculty of Health Sciences, McMaster University, Hamilton, Canada.
¹⁰ Department of Medicine and Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Canada.

PMID: 38158198
DOI: 10.1055/s-0043-1777827

Abstract

Background: Patients with a mechanical heart valve (MHV) require oral anticoagulation. Poor anticoagulation control is thought to be associated with adverse outcomes, but data are limited.

Objective: To assess the risks of clinical outcomes in patients with a MHV and poor anticoagulation control on warfarin.

Patients/methods: We conducted a retrospective study of consecutive patients undergoing MHV implantation at a tertiary care center (2010-2019). Primary outcome was a composite of ischemic stroke, systemic embolism, or prosthetic valve thrombosis. Major bleeding and death were key secondary outcomes. We constructed multivariable regression models to assess the association between time in therapeutic range (TTR) on warfarin beyond 90 days after surgery with outcomes.

Results: We included 671 patients with a MHV (80.6% in aortic, 14.6% in mitral position; mean age 61 years, 30.3% female). Median follow-up was 4.9 years, mean TTR was 62.5% (14.5% TTR <40%, 24.6% TTR 40-60%, and 61.0% TTR >60%). Overall rates of the primary outcome, major bleeding, and death were 0.73, 1.41, and 1.44 per 100 patient-years. Corresponding rates for patients with TTR <40% were 1.31, 2.77, and 3.22 per 100 patient-years. In adjusted analyses, every 10% decrement in TTR was associated with a 31% increase in hazard for the primary outcome (hazard ratio [HR]: 1.31, 95% confidence interval [CI]: 1.13-1.52), 34% increase in major bleeding (HR: 1.34, 95% CI: 1.17-1.52), and 32% increase in death (HR: 1.32, 95% CI: 1.11-1.57).

Conclusion: In contemporary patients with a MHV, poor anticoagulation control on warfarin was associated with increased risks of thrombotic events, bleeding, and death.

The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).