No statistically significant difference was found between the pacing modes for mortality , heart failure , stroke , chronic atrial fibrillation or quality of life .
However , the risk of developing heart failure may vary with age and device .
The risk of heart failure may have an impact on the decision to use dual-chamber or single-chamber atrial pacemakers .
Results from an analysis based on age ( > 75 years or ≤ 75 years ) and risk of heart failure indicate that dual-chamber pacemakers dominate single-chamber atrial pacemakers ( i.e. are less expensive and more effective ) in older patients , whereas dual-chamber pacemakers are dominated by ( i.e. more expensive and less effective ) single-chamber atrial pacemakers in younger patients .
In patients with SSS without evidence of impaired AV conduction , dual-chamber pacemakers appear to be cost-effective compared with single-chamber atrial pacemakers .
BACKGROUND Bradycardia [ resting heart rate below 60 beats per minute ( b.p.m . ) ]
can be caused by conditions affecting the natural pacemakers of the heart , such as sick sinus syndrome ( SSS ) and atrioventricular ( AV ) blocks .
People suffering from bradycardia may present with palpitations , exercise intolerance and fainting .
The only effective treatment for patients suffering from symptomatic bradycardia is implantation of a permanent pacemaker .
OBJECTIVE To appraise the clinical effectiveness and cost-effectiveness of dual-chamber pacemakers compared with single-chamber atrial pacemakers for treating symptomatic bradycardia in people with SSS and no evidence of AV block .
Effects of physiologic pacing versus ventricular pacing on the risk of stroke and death due to cardiovascular causes. Canadian Trial of Physiologic Pacing Investigators.
BACKGROUND Evidence suggests that physiologic pacing ( dual-chamber or atrial ) may be superior to single-chamber ( ventricular ) pacing because it is associated with lower risks of atrial fibrillation , stroke , and death . These benefits have not been evaluated in a large , r and omized , controlled trial . METHODS At 32 Canadian centers , patients without chronic atrial fibrillation who were scheduled for a first implantation of a pacemaker to treat symptomatic bradycardia were eligible for enrollment . We r and omly assigned patients to receive either a ventricular pacemaker or a physiologic pacemaker and followed them for an average of three years . The primary outcome was stroke or death due to cardiovascular causes . Secondary outcomes were death from any cause , atrial fibrillation , and hospitalization for heart failure . RESULTS A total of 1474 patients were r and omly assigned to receive a ventricular pacemaker and 1094 to receive a physiologic pacemaker .  The annual rate of stroke or death due to cardiovascular causes was 5.5 percent with ventricular pacing , as compared with 4.9 percent with physiologic pacing ( reduction in relative risk , 9.4 percent ; 95 percent confidence interval , -10.5 to 25.7 percent [ the negative value indicates an increase in risk ] ; P=0.33 ) . The annual rate of atrial fibrillation was significantly lower among the patients in the physiologic-pacing group ( 5.3 percent ) than among those in the ventricular-pacing group ( 6.6 percent ) , for a reduction in relative risk of 18.0 percent ( 95 percent confidence interval , 0.3 to 32.6 percent ; P=0.05 ) . The effect on the rate of atrial fibrillation was not apparent until two years after implantation . The observed annual rates of death from all causes and of hospitalization for heart failure were lower among the patients with a physiologic pacemaker than among those with a ventricular pacemaker , but not significantly so ( annual rates of death , 6.6 percent with ventricular pacing and 6.3 percent with physiologic pacing ; annual rates of hospitalization for heart failure , 3.5 percent and 3.1 percent , respectively ) . There were significantly more perioperative complications with physiologic pacing than with ventricular pacing ( 9.0 percent vs. 3.8 percent , P<0.001 ) . CONCLUSIONS Physiologic pacing provides little benefit over ventricular pacing for the prevention of stroke or death due to cardiovascular causes
No statistically significant difference was found between the pacing modes for mortality , heart failure , stroke , chronic atrial fibrillation or quality of life .
However , the risk of developing heart failure may vary with age and device .
The risk of heart failure may have an impact on the decision to use dual-chamber or single-chamber atrial pacemakers .
Results from an analysis based on age ( > 75 years or ≤ 75 years ) and risk of heart failure indicate that dual-chamber pacemakers dominate single-chamber atrial pacemakers ( i.e. are less expensive and more effective ) in older patients , whereas dual-chamber pacemakers are dominated by ( i.e. more expensive and less effective ) single-chamber atrial pacemakers in younger patients .
In patients with SSS without evidence of impaired AV conduction , dual-chamber pacemakers appear to be cost-effective compared with single-chamber atrial pacemakers .
BACKGROUND Bradycardia [ resting heart rate below 60 beats per minute ( b.p.m . ) ]
can be caused by conditions affecting the natural pacemakers of the heart , such as sick sinus syndrome ( SSS ) and atrioventricular ( AV ) blocks .
People suffering from bradycardia may present with palpitations , exercise intolerance and fainting .
The only effective treatment for patients suffering from symptomatic bradycardia is implantation of a permanent pacemaker .
OBJECTIVE To appraise the clinical effectiveness and cost-effectiveness of dual-chamber pacemakers compared with single-chamber atrial pacemakers for treating symptomatic bradycardia in people with SSS and no evidence of AV block .