Cause of Death and Predictors of All-Cause Mortality in Anticoagulated Patients With Nonvalvular Atrial Fibrillation : Data From ROCKET AF

M. Kaste on työryhmän ROCKET AF Steering Comm jäsen.Background-Atrial fibrillation is associated with higher mortality. Identification of causes of death and contemporary risk factors for all-cause mortality may guide interventions. Methods and Results-In the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF) study, patients with nonvalvular atrial fibrillation were randomized to rivaroxaban or dose-adjusted warfarin. Cox proportional hazards regression with backward elimination identified factors at randomization that were independently associated with all-cause mortality in the 14 171 participants in the intention-to-treat population. The median age was 73 years, and the mean CHADS(2) score was 3.5. Over 1.9 years of median follow-up, 1214 (8.6%) patients died. Kaplan-Meier mortality rates were 4.2% at 1 year and 8.9% at 2 years. The majority of classified deaths (1081) were cardiovascular (72%), whereas only 6% were nonhemorrhagic stroke or systemic embolism. No significant difference in all-cause mortality was observed between the rivaroxaban and warfarin arms (P=0.15). Heart failure (hazard ratio 1.51, 95% CI 1.33-1.70, P= 75 years (hazard ratio 1.69, 95% CI 1.51-1.90, P Conclusions-In a large population of patients anticoagulated for nonvalvular atrial fibrillation, approximate to 7 in 10 deaths were cardiovascular, whereasPeer reviewe

Hemodynamiek en pacing

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Evaluation of six minute walking test in patients with single chamber rate responsive pacemakers

Objective : To validate a simplified exercise protocol (the six minute walk) as a means of evaluating pacing modes and rate responsive pacemakers. Design : Two groups of patients with different pacemaker types (activity and dual sensor) were randomly assigned to four consecutive pacing settings (fixed rate-or VVI at 60, 85, and 110/min, and optimal rate response-or VVIR). A third group of elderly patients without arrhythmias or conduction disturbances formed a control population. Setting : Ambulatory consultation for patients with a pacemaker in a tertiary referral centre for treatment of arrhythmias. Subjects : 16 patients with rate responsive pacemakers for complete heart block and limited functional capacity and 13 controls with normal chronotropic competence. Subjects : 16 patients with rate responsive pacemakers for complete heart block and limited functional capacity and 13 controls with normal chronotropic competence. Interventions : Submaximal exercise protocol with 6 minutes walking and continuous recording of electrocardiogram. Main outcome measures : Achieved distance and scored degree of exertion during walking in the four settings in the patients with a pacemaker; differences in rate behaviour in VVIR mode between the two pacemaker types; comparison of the pacing rate with the heart rate of the control population. Results : The six minute walk was performed better in VVIR than VVI 60. In VVI 85 the distance was also significantly longer than in VVI 60. The rise in pacing rate of activity pacemakers was steeper than that of the dual sensor pacemakers and differed from the heart rate in the controls at 90 seconds. Conclusions : The studied test protocol was able to show differences in exercise capacity between pacing modes. Different rate responses between the evaluated sensor types could be established. The six minute walking test gives enough information to program and reprogram single chamber rate responsive pacemakers

Hémodynamique et stimulation cardiaque

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Low-energy intracardiac shocks during atrial fibrillation: effects on cardiac rhythm

The effect on ventricular rate of intracardiac shocks for atrial fibrillation was studied in 13 patients receiving 95 shocks. Shocks were synchronized to the R wave and were delivered after R-R intervals >500 msec, with increasing strength (20 to 400 V). In 10 patients, conversion to sinus rhythm was achieved in this way. Noneffective shocks increased the mean first postshock R-R interval (compared with 20 V as baseline), for shocks greater than or equal to 140 V. The R-R prolongation correlated with the shock level (r = 0.936, p 1500 msec tended to increase with voltage (noneffective shocks). Pauses >2500 msec were exceptional (4 of 85 noneffective shocks). No symptomatic bradycardia occurred. In subsequent intervals (cycles 2 through 10) no pauses >2500 msec were noted. It is concluded that atrial defibrillation attempts between the right atrium and coronary sinus prolong R-R intervals, in relation to administered energy, but without the need for backup pacing