We thank Xu et al (2025)1 for their insightful comments on our article.2 We agree that our findings suggest that outcomes are likely to be similar across different bileaflet mechanical aortic valve models. However, we would like to emphasize once again that these findings must be interpreted cautiously due to the study design and the lack of INR values.
Optimizing the care of patients who have undergone mechanical aortic valve replacement (AVR) remains an important clinical priority. This is critical in vulnerable patient groups who are at increased risk of bleeding complications, for example, those with low socioeconomic status, prior bleeding complications, and older patients.3
Lower INR targets after mechanical AVR may help improve patient outcomes. We welcome the ongoing and important LIMIT trial (https://clinicaltrials.gov/study/NCT03636295), and find it encouraging that the international survey conducted prior to the trial clearly showed that clinicians were indeed willing to randomize patients to lower INR strategies.
Parallel initiatives to improve patient care following mechanical AVR should also be explored. These may include expanding patient education and access to INR home monitoring, possibly increasing the time in therapeutic range. Furthermore, investigating alternatives to warfarin, such as direct oral anticoagulants, remains of interest, even though previous trials were terminated early due to unfavorable outcomes. However, as far as we understand, the RENOVATE trial (https://clinicaltrials.gov/study/NCT4258488) is currently underway in South Korea. The RENOVATE trial compares rivaroxaban with warfarin in patients following mechanical AVR. Comparable performance has been demonstrated among different mechanical valve types,4 and therefore, these different strategies to improve care in patients with mechanical valves are likely applicable to all modern mechanical aortic valve prostheses.
Determining whether a lower target INR after mechanical AVR is safe and effective remains a top priority. In parallel, alternative approaches to reduce bleeding risks while maintaining comparable protection against thromboembolic events should also be explored.
CONFLICT OF INTEREST STATEMENT
None declared.
Contributor Information
Ruixin Lu, Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, 171 76, Sweden.
Michael Dismorr, Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, 171 76, Sweden; Department of Cardiology, Danderyd Hospital, Stockholm, 182 88, Sweden.
Natalie Glaser, Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, 171 76, Sweden; Department of Cardiology, Stockholm South General Hospital, Stockholm, 118 83, Sweden.
Ulrik Sartipy, Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, 171 76, Sweden; Department of Cardiothoracic Surgery, Karolinska University Hospital, Stockholm, 171 76, Sweden.
DATA AVAILABILITY STATEMENT
The data underlying this article cannot be shared publicly due to data protection regulations.
REFERENCES
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Associated Data
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Data Availability Statement
The data underlying this article cannot be shared publicly due to data protection regulations.