We also looked at antithrombotic therapy for each
We also looked at antithrombotic therapy for each CHADS2 score in each country. For patients with CHADS2 score of 0 (Fig. 3), approximately 80% of the physicians used antiplatelet agents in 6 of the countries—Australia, China, Korea, Taiwan, Hong Kong, and Singapore. A total of 59% of the physicians used antiplatelet agents in New Zealand, and 34% (64%, if concomitant use with OACs was included) in India. In Japan, 16% of the physicians used antiplatelet agents (36% used OAC, 46% provided no treatment); thus, the treatment stance in Japan is rather unique.
For patients with CHADS2 score of 1 (Fig. 4), India has a very unique treatment stance, in that 70% of the physicians used antiplatelet agents alone and 28% in combination. In contrast, 70% of the physicians used OACs in Japan, followed by 65% in Singapore and 54% in New Zealand; thus, OACs are actively used for relatively low-risk patients in these countries. In other countries, 30–50% of the physicians used OACs.
For patients with CHADS2 score of 2 (Fig. 5), the frequency of use of OACs (including warfarin, direct thrombin inhibitor, and their concomitant use with antiplatelets) is high (100% in Australia, Hong Kong, New Zealand, and Singapore). Surprisingly, 50% of physicians in India used antiplatelet agents alone. For patients with CHADS2 score of 2 with stroke, a similar trend was observed.
It can be summarized that the frequency of use of OACs was high in patients with a CHADS2 score of 2, in accordance with the guidelines, except in India. The countries had different treatment stances for low-risk patients with a CHADS2 score of 0/1. It is important to reach a consensus on the treatment of this SW033291 patient group when preparing the APHRS\'s statement. In particular, in Japan, evidence  that ASA use only increases the bleeding risk and has no embolism-preventing effect is incorporated in the JCS 2008 guidelines, and follow-up without treatment or the use of OACs, if any treatment is provided, is recommended. On the other hand, in India, 70% of physicians use antiplatelet agents even for patients with a CHADS2 score of 1.
Problems with warfarin therapy There are 2 important problems with the use of warfarin in the clinical setting. The first problem is underuse. Of patients with nonvalvular AF and no known contraindications, 55% received warfarin. Warfarin use was substantially lower in elderly patients in whom warfarin therapy is believed essential . Many registration studies in Europe and the United States consistently revealed underuse of warfarin in patients with a higher risk for stroke [26–28]. In the present survey by the APHRS, 60% of high-risk patients with a CHADS2 score of 2 received warfarin. The second problem is suboptimal regimens among patients receiving warfarin. Patients who achieved an optimal INR (2.0–3.0) accounted for about 50%. To maximize the efficacy of warfarin therapy, the time in therapeutic range (TTR) should be at least 60% .
Discontinuation of anticoagulants before surgery and other invasive procedures that cause bleeding Garcia et al.  discussed 2 questions: (1) For how long should the anticoagulant be stopped before the procedure? and (2) Should a bridging strategy be used with heparin? Since patients with AF may be left with suboptimal protection against stroke for several days before and after surgery during which time warfarin therapy is suspended, bridging therapy with heparin or other drugs has been recommended for patients with a high risk for stroke, although there is little reliable evidence that bridging therapy benefits patients with AF. Observational studies indicate that many (if not most) AF patients who simply interrupt warfarin for 7 days (without bridging therapy) have a very low risk for stroke. On the other hand, treatment with novel OACs with a half-life of ≤12h may be suspended immediately before surgery and restarted promptly after surgery. Healey et al.  reported the outcome of patients with AF who discontinued anticoagulant therapy at least once for invasive procedures during the RE-LY (Randomized Evaluation of Long-term Anticoagulation Therapy) trial. Patients discontinued anticoagulation therapy on average 2 and 5 days before the procedure in the dabigatran and warfarin groups, respectively, and only a portion of the patients received periprocedural bridging therapy (28.5% in the warfarin group and 16% in the dabigatran group). Perioperative thromboembolic events developed in only 21 of 4591 patients (0.5%), and the incidence of postoperative bleeding complications was 4–5% with no significant difference between the 2 groups. The incidence of stroke or systemic embolism was quite low both in the dabigatran and warfarin groups after short-term discontinuation of anticoagulant therapy. The duration of anticoagulant discontinuation for surgery was shorter in the dabigatran group than in the warfarin group. These findings suggest that novel shorter-acting OACs are more beneficial in patients expected to undergo surgery or invasive procedures that cause bleeding.