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 .
Early complications of permanent pacemaker implantation: no difference between dual and single chamber systems.
OBJECTIVE --To evaluate the incidence of intraoperative and early postoperative complications ( up to two months after implant ) of endocardial permanent pacemaker insertion in all patients under-going a first implant at a referral centre . METHODS -- Prospect i ve evaluation of all  endocardial pacemaker implantation procedures performed from April 1992 to January 1994 carried out by completion of st and ard audit form at implant . Patients ' demographic data , medical history , details of pacemaker hardware used , and any complications were noted . Follow up information was also collected prospect ively onto st and ard forms at pacemaker outpatient clinic . SETTING --United Kingdom tertiary referral cardiothoracic centre . PATIENTS --1088 consecutive patients underwent implantation of their first endocardial permanent pacemaker from April 1992 to January 1994 . Implant and follow up data were available for 1059 ( 97.3 % ) patients at analysis . The median ( range ) age was 77 years ( 16 - 99 ) ; 51.2 % were male . RESULTS --Dual chamber units were implanted in 54.1 % of patients , single chamber atrial in 5.2 % , and ventricular in 40.7 % . A temporary pacing lead was present at implant in 22.9 % of patients . Most ( 93.6 % ) implants were performed via the subclavian vein . Immediate complications were rare : eight ( 0.8 % ) patients developed pneumothorax requiring medical treatment and 11 ( 1.0 % ) an insignificant pneumothorax . There was no significant difference in the pneumothorax rate for dual chamber ( DDD ) compared with single chamber systems . Arterial puncture without sequelae was documented in 2.7 % of attempts at subclavian vein cannulation . A total of 35 patients ( 3.3 % ) required reoperation ; the reoperation rate for dual chamber ( 3.5 % ) was similar to that for single chamber ( 3.1 % ) systems . Electrode displacement ( n = 15 , 1.4 % ) was the most common reason for reoperation . Atrial lead displacement ( n = 10 , 1.6 % of atrial leads ) was significantly more common than ventricular lead displacement ( n = 5 , 0.5 % of ventricular leads , P = 0.047 ) . There was no difference in electrode displacement rates for dual ( 1.6 % ) compared with single ( 1.2 % ) chamber systems . Pacemaker pocket infection led to reoperation in 10 patients ( six dual , four single chamber , P = not significant ) and was significantly more common in patients who had a temporary pacing lead in place at implant ( 2.9 % ) than in those who did not ( 0.4 % , P = 0.0014 ) . Five patients ( 0.5 % ) required reoperation for generator erosion ( two dual , three single chamber , P = not significant ) . and a further five for drainage of haematoma or a serous fluid collection ( three dual , two single chamber , P = not significant ) . Complications that did not require reoperation were also rare . Undersensing occurred in 10 patients ( 0.9 % ) . Atrial undersensing ( n = 8) was significantly more common than ventricular undersensing ( n = 2 , P = 0.017 ) . All patients were successfully treated by reprogramming of sensitivity . Superficial wound infection was treated successfully with antibiotics in nine patients ( six dual , three single chamber , P = not significant ) . Three patients with DDD generators developed sustained atrial fibrillation : two required reprogramming to VVI mode and one required cardioversion . CONCLUSIONS --Permanent pacing in a large tertiary referral centre with experienced operators carries a low risk . Infection rates are low , < 1 % overall but significantly higher in patients who undergo temporary pacing before implantation . Lead displacement and undersensing are more likely to occur with atrial than ventricular leads . The overall complication rate for dual chamber pacing , however , is no higher than for single chamber pacing
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 .