Cardiac resynchronization therapy in patients with atrial fibrillation: a meta-analysis
Cláudia Lopes1, Telmo Pereira, Sérgio Barra
1Escola Superior de Tecnologia das Saúde de Coimbra, Departamento de Cardiopneumologia, Coimbra, Portugal. claudia.o.lopes@hotmail.com
Insights
Patients with atrial fibrillation (AF) have a higher risk of death and poor response to cardiac resynchronization therapy (CRT). However, atrioventricular nodal ablation may improve CRT outcomes in these patients.
Area of Science:
- Cardiology
- Electrophysiology
- Heart Failure Management
Background:
- Atrial fibrillation (AF) is a common comorbidity in heart failure (HF) patients.
- The efficacy of cardiac resynchronization therapy (CRT) may be influenced by cardiac rhythm.
Purpose of the Study:
- To compare the effectiveness of CRT in heart failure patients with AF versus those in sinus rhythm (SR).
- To evaluate the impact of atrioventricular nodal ablation on CRT outcomes in AF patients.
Main Methods:
- Systematic review and meta-analysis of randomized controlled trials and cohort studies.
- Inclusion of studies published up to November 2012.
- Analysis of endpoints including all-cause mortality, cardiovascular mortality, and CRT response.
Main Results:
- Patients with AF showed higher all-cause mortality (OR = 1.69) and a greater likelihood of non-response to CRT (OR = 1.41) compared to SR patients.
- No significant difference in cardiovascular mortality was observed between AF and SR groups.
- Atrioventricular nodal ablation in AF patients significantly reduced all-cause mortality (OR = 0.42), cardiovascular death (OR = 0.39), and CRT non-response (OR = 0.30).
Conclusions:
- Atrial fibrillation is associated with increased all-cause mortality and reduced CRT response in heart failure patients.
- Despite rhythm challenges, many AF patients still benefit from CRT.
- Atrioventricular nodal ablation enhances CRT benefits for heart failure patients with AF.
Background And Objective:
To combine the results of the best scientific evidence in order to compare the effects of cardiac resynchronization therapy (CRT) in heart failure patients with atrial fibrillation (AF) and in sinus rhythm (SR) and to determine the effect of atrioventricular nodal ablation in AF patients.
Methods:
The electronic databases PubMed, B-On and Cochrane CENTRAL were searched, and manual searches were performed, for randomized controlled trials and cohort studies up to November 2012. The endpoints analyzed were all-cause and cardiovascular mortality and response to CRT.
Results:
We included 19 studies involving 5324 patients: 1399 in AF and 3925 in SR. All-cause mortality was more likely in patients with AF compared to patients in SR (OR = 1.69; 95% CI: 1.20–2.37; p = 0.002). There were no statistically significant differences in cardiovascular mortality (OR = 1.36; 95% CI: 0.92–2.01; p = 0.12). AF was associated with an increased likelihood of lack of response to CRT (OR = 1.41; 95% CI: 1.15–1.73; p = 0.001). Among subjects with AF, ablation of the atrioventricular node was associated with a reduction in all-cause mortality (OR = 0.42; 95% CI: 0.22–0.80; p = 0.008), cardiovascular death (OR = 0.39; 95% CI: 0.20–0.75; p = 0.005) and the number of non-responders to CRT (OR = 0.30; 95% CI: 0.10–0.90; p = 0.03).
Conclusions:
The presence of AF is associated with increased likelihood of all-cause death and non-response to CRT, compared to patients in SR. However, many patients with AF benefit from CRT. Atrioventricular nodal ablation appears to increase the benefits of CRT in patients with AF.
