Introduction: Atrial fibrillation (AF) is the most common arrhythmia in patients undergoing hemodialysis (HD), which lowers the quality of life (QoL) and increases the risk of dialysis related complications. The present study aimed to evaluate the effectiveness of AF ablation on the QoL in patients undergoing HD. Methods and Results: Nineteen patients undergoing HD (14 men, age 68±8years, 15 paroxysmal AF) who underwent catheter ablation (CA) of drug-refractory AF were enrolled in the study. The ablation outcomes and procedural complications were evaluated and compared to 1053 consecutive patients without HD who underwent AF ablation. The Kidney Disease Quality of Life Short Form (KDQOL-SF) was assessed to evaluate the QoL of the HD patients at baseline and six months after the ablation. During the follow-up period of 17±13 months after the last procedure, the arrhythmia free rate was similar (HD patients 79% vs. non-HD patients 86%, log-rank p=0.82). There were no life-threatening complications in any patients. The KDQOL-SF of the HD patients six months after the ablation showed an improvement in the physical functioning (54±23 to 68±28, p<0.01), general health perceptions (38±17 to 48±15, p<0.01) and symptoms/problems (75±21 to 84±13, p=0.02) as compared to the baseline. Regarding the intradialytic symptoms, the dyspnea during HD significantly improved after the CA in the HD patients without AF recurrence (35% to 6%, p=0.04), while the atrial tachyarrhythmias and hypotension during HD remained unchanged. Conclusions: CA of AF improves the QoL in patients with chronic hemodialysis.

Background: Atrial flutter (AFL) is a large re-entrant circuit located in the right atrium. Anti-arrhythmic drugs (AADs) can provoke AFL with 1:1 atrioventricular conduction (AVC) to cause hemodynamic collapse. We elucidated the characteristics of patients with AFL exhibiting spontaneous 1:1 AVC. Methods: Fifteen patients (1:1 AFL group; 11 males, 52.4±13.7 years old) who documented AFL with 1:1 AVC were enrolled and compared to 77 patients without 1:1 AVC (Control group; 71 males, 68.1±10.9 years old). Results: The use of AADs was greater in the 1:1 AFL group than in the control group (60.0 vs. 14.3%, p < 0.001). AFL cycle length during maximum AVC was significantly longer in the 1:1 AFL group than in the control group (274.7 ± 37.0 vs. 220.4 ± 26.2 msec, p < 0.001). Among 1:1 AVC group, 9 patients had AADs and AFL cycle length was significantly longer during 1:1 AVC as compared with 2:1 AVC documented the other day (284.4 ± 41.3 vs. 233.3 ± 26.0 msec, p <0.001), suggesting enhancement effect of the AADs during 1:1 AVC. Remaining 6 patients who did not take AADs, 2 patients showed enlargement of the tricuspid annulus and 3 patients developed 1:1 AVC during exercise. Conclusions: In addition to the enhancement of AAD effect, prolonged AFL cycle length associated with enlargement of the tricuspid annulus and shortened refractory period of the AV node might increase the risk of 1:1 AVC during AFL. Keywords: atrial flutter, atrial flutter cycle length, tricuspid annulus. Atrioventricular node, atrioventricular conduction, anti-arrhythmic drug