Correspondence Response to Letter Regarding Article, “New Oral Anticoagulants Should Not Be Used as First-Line Agents to Prevent Thromboembolism in Patients

I thank Dr Christensen et al for their comments about the quality of anticoagulation control and its importance in understanding the value of vitamin K antagonists versus the new target-specific oral anticoagulants, which I had mentioned in my study.1 I also support their comments about the impact of patient self-testing and patient self-management in providing greater time in therapeutic interna-tional normalized ratio range. Not only has this been demonstrated in retrospective and prospective clinical trials,2 but also in real-world patient self-testing in the United States where rates of time in range are found to be in the 69 % to 74 % range depending on the frequency of testing3 compared with the usual modalities of international normalized ratio monitoring where time in interna-tional normalized ratio range is in the 50 % to 55 % range across the United States.4 The new target-specific oral anticoagulants have many favorable attributes in comparison with the vitamin K antagonists, and they will clearly impact the market for stroke prevention in atrial fibrillation. Their value will be greatest when warfarin management is poor and least when international nor-malized ratio management is ideal