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Published on: February 28, 2012
Emergency pacemaker implantation in nonagenarians with CHB: single-versus dual-chamber pacing
Karishma Mahtani1, Edd Maclean2, Maurizio Parker3
1Medical Student.
Insights
For nonagenarians with emergent complete heart block (CHB), dual-chamber (DDD) pacing significantly reduces mortality risk compared to single-chamber (VVI) pacing. This study highlights DDD pacing as a superior choice for improved outcomes in this elderly population.
Area of Science:
- Cardiology
- Geriatrics
- Biomedical Engineering
Background:
- Dual-chamber (DDD) pacing offers physiological benefits over single-chamber (VVI) pacing in complete heart block (CHB), but its impact on mortality remains debated.
- Nonagenarians are an increasing demographic for pacemaker implantation, yet data on device selection and outcomes, particularly in emergencies, are scarce.
- Emergent CHB in nonagenarians presents unique challenges for device management and prognostic assessment.
Purpose of the Study:
- To compare the clinical characteristics and outcomes of nonagenarian patients with emergent CHB who received either VVI or DDD pacemakers.
- To evaluate the association between pacemaker type (VVI vs. DDD) and all-cause mortality or death from congestive cardiac failure (CCF) in this population.
- To identify factors influencing device selection and patient prognosis in nonagenarians with emergent CHB.
Main Methods:
- A retrospective study analyzing 168 consecutive nonagenarian patients with emergent CHB over a median follow-up of 30.6 months.
- Patients were divided into two groups based on pacemaker type: VVI (n=22) and DDD (n=146).
- Cox proportional-hazards analysis was employed to assess all-cause mortality and CCF-related death, adjusting for covariates like age, frailty (Rockwood scale), and dementia.
Main Results:
- VVI recipients were significantly frailer and more likely to have dementia compared to DDD recipients, despite similar age and left ventricular ejection fraction.
- Post-implant, VVI patients exhibited higher respiratory rates, lower mean heart rates, and reduced daily activity levels compared to DDD patients.
- Adjusted analysis revealed that VVI pacing was associated with a 2.1-fold increased risk of all-cause mortality (HR 2.1, p=0.03) and a 7.1-fold increased risk of death from CCF (HR 7.1, p<0.001).
Conclusions:
- In nonagenarians experiencing emergent CHB, dual-chamber pacing is associated with improved symptomatic status and better prognostic outcomes compared to single-chamber pacing.
- The findings suggest that DDD pacing should be strongly considered in nonagenarian patients with emergent CHB, even in emergency settings, to mitigate mortality risks.
- Frailty and dementia are significant factors in this population and should be considered during pacemaker selection and management.
Abstract:
In ambulatory patients with complete heart block (CHB), dual-chamber (DDD) pacing confers physiological benefits versus single-chamber (VVI) pacing, however, the impact on mortality is disputed. Nonagenarians constitute an expanding proportion of pacemaker recipients, yet data on device selection and outcomes are limited, especially in emergency situations. In nonagenarians with emergent CHB, we compared the clinical characteristics and outcomes of patients receiving VVI versus DDD pacemakers. Cox proportional-hazards analysis examined all-cause mortality and death from congestive cardiac failure (CCF). There were 168 consecutive patients followed-up for 30.6 ± 15.5 months. Of these, 22 patients (13.1%) received VVI pacemakers; when compared with DDD recipients, these patients had similar median age (93 vs. 91 years, p=0.15) and left ventricular (LV) systolic function (LV ejection fraction [EF] 49.2% ± 9.7 vs. 50.7% ± 10.1, p=0.71), but were more frail (Rockwood scale 5.2 ± 1.8 vs. 4.3 ± 1.1, p=0.004) and more likely to have dementia (27.3% vs. 8.9%, p=0.011). Post-implant, device interrogation demonstrated that VVI recipients had higher respiratory rates (21.3 ± 2.4 vs. 17.5 ± 2.6 breaths per minute, p=0.002), lower mean heart rates (65.5 ± 10.1 vs. 71.9 ± 8.6 bpm, p=0.002), and lower daily activity levels (0.57 ± 0.3 vs. 1.5 ± 1.1 hours of activity, p=0.016) than DDD recipients. Adjusting for age, frailty and dementia, VVI pacing was associated with an increased risk of all-cause mortality (adjusted hazard ratio [HR] 2.1, 95% confidence interval [CI] 1.08 to 4.1, p=0.03) and death from CCF (adjusted HR 7.1, 95%CI 2.5 to 20.6, p<0.001). In conclusion, in nonagenarians with emergent CHB, dual-chamber pacing was associated with improved symptomatic and prognostic outcomes versus singlechamber pacing.
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