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 .
Rate adaptive pacing in sick sinus syndrome: effects of pacing modes and intrinsic conduction on physiological responses, arrhythmias, symptomatology and quality of life.
An atrial-based pacing mode is superior to ventricular constant rate dem and pacing ( VVI ) mode in patients with sick sinus syndrome ( SSS ) by providing both rate adaptation and atrioventricular ( AV ) synchrony . The use of a non-atrial sensor to overcome chronotropic incompetence and preserve normal intrinsic AV conduction in pacemaker therapy for SSS was investigated in 15 consecutive patients ( mean age 66 + /- 2 years ) . All had intact AV conduction ( ante grade conduction capacity > 100 beats.min-1 and an atrial paced to intrinsic R interval of < or = 220 ms ) .  DDDR pacemakers capable of being programmed into atrial rate adaptive ( AAIR ) , dual chamber rate adaptive ( DDDR ) and ventricular rate adaptive ( VVIR ) modes were used . Beginning with an acute study , arterial pressure was invasively assessed in each pacing mode during physiological stresses and low level exercise . In the ambulatory phase , the incidence of ventricular pacing and arrhythmias ( Holter recording ) , diurnal blood pressure changes ( ambulatory blood pressure recording ) , and symptom and quality of life level ( question naires and interviews ) were compared . Despite similar heart rate changes during acute physiological stresses , a higher blood pressure was recorded during AAIR or DDDR pacing compared with VVIR pacing . Systolic blood pressure over 24 h was lower in the VVIR mode ( 122 + /- 5 mmHg ) than AAIR/DDDR pacing ( 129 + /- 6/128 + /- 6 mmHg , P < 0.05 ) . VVIR pacing was associated with a higher frequency of atrial and ventricular ectopics , with two patients developing paroxysmal atrial fibrillation . Ventricular pacing was used in a higher percentage in the DDDR compared with the VVIR mode ( 64 + /- 11 and 39 + /- 7 % , P < 0.03 ) . VVIR pacing was associated with more palpitations , a lower level of general well being and depression . Despite the use of a sensor to overcome chronotropic incompetence , VVIR pacing is a less satisfactory pacing mode for SSS . Although AAIR/DDDR pacing may achieve similar haemodynamic and clinical status , in patients with intact AV conduction , AAIR pacing may be preferable by avoiding an abnormal ventricular activation pattern
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 .