Letters Section Editor: Jody W. Zylke, MD, Senior Editor.
Author Affiliations: Department of Cardiology, Copenhagen University Hospital Gentofte (Drs Mérie and Torp-Pedersen) (firstname.lastname@example.org); and Department of Cardiology, Copenhagen University Hospital Rigshospitalet (Dr Køber), Copenhagen, Denmark.
In Reply: The current strategy of recommending anticoagulation for 3 months after bioprosthetic AVR is based on small observational studies that had limited power for examining thrombosis more than 3 months after the operation. We performed a much larger observational study that indicated a benefit of warfarin treatment up to 6 months after surgery.
The basic argument by Dr Toeg and colleagues is that our study was observational and may have suffered from confounding by indication, making any conclusions uncertain. We agree but maintain that we have provided the best information available at this time. We also agree with the Editorial1 that until better evidence is available, a recommendation of 6 months of warfarin should be made.
Mérie C, Køber L, Torp-Pedersen C. Warfarin Treatment After Bioprosthetic Aortic Valve Replacement—Reply. JAMA. 2013;309(12):1225-1226. doi:10.1001/jama.2013.1978