Shunsuke Imai

Recovery of the right atrial effective refractory period after cardioversion of chronic atrial fibrillation

The effective refractory period was shorter in patients with than without chronic atrial fibrillation (AF). The effective refractory period was prolonged, and at 12 and 24 hours after cardioversion of AF it was the same as the subjects without AF.

Clinical characteristics of hemodialysis patients with atrial fibrillation: The RAKUEN (Registry of atrial fibrillation in chronic kidney disease under hemodialysis from Niigata) study

BACKGROUND Clinical characteristics, management, and outcomes in hemodialysis patients with atrial fibrillation (AF) remain unclear. METHODS AND RESULTS We studied 423 Japanese patients undergoing maintenance hemodialysis (age 65.2±12.4 years, male 70%, mean duration of hemodialysis 139±124 months). AF was present in 19% (n=82) and was independently related to increased age (odds ratio 1.070, 95% confidence interval 1.043-1.098), longer hemodialysis duration (odds ratio 1.006, 95% confidence interval 1.004-1.008), and congestive heart failure (odds ratio 2.749, 95% confidence interval 1.546-4.891). During observations lasting a mean of 36 months, the incidences of all-cause death, cardiovascular death, and major bleeding, in particular gastrointestinal bleeding, were significantly higher in the AF (n=82) than the non-AF (n=341) patients (p<0.001, p=0.004, p=0.002, p=0.027, respectively), but the incidence of ischemic stroke/systemic embolism was similar in the AF and non-AF patients. AF was independently associated with all-cause death (hazard ratio 1.728, 95% confidence interval 1.123-2.660) and major bleeding (hazard ratio 1.984, 95% confidence interval 1.010-3.896). Warfarin was prescribed in 33% of the AF patients, but the rates of all-cause death, ischemic stroke, and major bleeding during the study period were not significantly different between warfarin (n=27) and non-warfarin (n=55) groups. CONCLUSIONS In our hemodialysis patients, AF was a common comorbidity and was independently associated with all-cause death and major bleeding, but not with increased risk of ischemic stroke.

Atrial Fibrillation had Less Impact on the Risk of Ischemic Stroke in Non-anticoagulated Patients Undergoing Hemodialysis: Insight from the RAKUEN study

Objective The progress of non-anticoagulated patients with atrial fibrillation (AF) undergoing hemodialysis has not been determined. Using data from the RAKUEN (Registry of Atrial fibrillation in chronic Kidney disease Under hEmodialysis from Niigata) study, we examined the clinical characteristics and outcomes among hemodialysis patients with AF who were not receiving a vitamin K antagonist (VKA). Methods and Results Forty-three of 423 patients undergoing hemodialysis (-10%) were prescribed a VKA. The remaining 380 patients (age 64.8±12.8 years, male 70%) were enrolled in the present study. During a mean observation period of 36 months, AF (n=55) was independently associated with all-cause death (hazard ratio, 1.82; 95% confidence interval, 1.12-2.94; p=0.014), but was not associated with ischemic stroke (hazard ratio, 1.91; 95% confidence interval, 0.74-4.92; p=0.177) and major bleeding (hazard ratio, 1.80; 95% confidence interval, 0.80-4.08; p=0.150). The crude incidence rates of all-cause death and ischemic stroke in the AF patients were 15.75 (2.5-fold higher compared to the non-AF patients) and 3.63 (1.7-fold higher compared to the non-AF patients) per 100 person-years, respectively. Conclusion A great impact on death, but not ischemic stroke, was observed in non-anticoagulated hemodialysis patients with AF in comparison to those without AF from the analysis of the RAKUEN study.