Author + information
- Christina Ji-Young Lee, MD, PhD∗ ( and )
- Christian Torp-Pedersen, MD, DMSC
- ↵∗Aalborg University Hospital, Unit of Epidemiology and Biostatistics, Søndre Skovvej 15, 9000 Aalborg, Denmark
We would like to thank both Dr. Aloia and Drs. Ye and colleagues for their comments about our study (1).
A concern about our study is the observational nature, and therefore, the results should be interpreted with caution. Residual confounding cannot be excluded, and we agree that it might be a limitation to our study that the international normalized ratio was not available, as Ye and colleagues commented. However, our results were robust in the sensitivity analyses. Dr. Aloia commented on the higher baseline of prior ischemic heart disease in the vitamin K antagonist (VKA) treatment group. Our sensitivity analyses of the VKA group compared with the direct oral anticoagulants (DOACs) for patients stratified into low and high risk dependent on prior ischemic heart disease/percutaneous coronary intervention, use of ADP inhibitors, or acetylsalicylic acid showed similar results as our primary analyses.
Studies have been missing comparing the DOACs directly in the risk of myocardial infarction, and in a larger scale comparing the DOACs; our study is also one of the largest studies investigating the risk of myocardial infarction with the use of DOACs and VKA. The observational nature also allows the inclusion of the old and the frail. Our observational study suggests that there is a low risk of myocardial infarction with the use of DOACs compared with VKA, and until better evidence becomes available from randomized studies, the result should provide some reassurance to the use of DOACs in patients with ischemic heart disease.
Please note: Dr. Torp-Pedersen has received research funding from Bayer and Biotronik. Dr. Lee has reported that he has no relationships relevant to the contents of this paper to disclose.
- 2018 American College of Cardiology Foundation