Clinical InvestigationCongestive Heart FailureEffect of QRS morphology on clinical event reduction with cardiac resynchronization therapy: Meta-analysis of randomized controlled trials
Section snippets
Literature search
A systematic search of MEDLINE through January 2011 was performed to identify all published randomized controlled trials of CRT that reported clinical outcomes (including death and heart failure hospitalizations) according to bundle-branch block morphology. MEDLINE search terms of (heart failure and cardiac resynchronization therapy) limited to randomized controlled trials returned 113 articles. Additional search of the FDA website returned an additional trial with extractable data. The
Search results
The results of the literature search are shown in Figure 1. A total of 4 randomized controlled trials enrolling 5,356 patients (3,009 CRT, 2,347 controls) met the inclusion criteria for this meta-analysis.10, 11, 12, 13, 14 The PRISMA guideline for reporting meta-analyses is presented in the online Appendix A. A list of excluded trials and the reasons for exclusion are presented in the online Appendix B.
Study characteristics
Trial characteristics are presented in Table I. The COMPANION10 trial had 3 arms (medical
Discussion
Our results show that in patients with a LBBB, CRT is very effective in reducing adverse events with a relative risk reduction of 36% (P = .00001). Conversely, no benefit was observed in patients with other types of conduction abnormalities and a QRS duration >120 milliseconds. The narrow confidence interval for patients with QRS prolongation not due to LBBB rules out even a 20% relative risk reduction for these patients (P = .75).
The majority of studies evaluating CRT in patients with non-LBBB
Acknowledgements
Contributors:
Study concept and design - Sipahi, Fang.
Literature search - Sipahi, Chou, Hyden.
Data collection - Sipahi, Hyden.
Statistical analysis – Sipahi, Rowland.
Analysis and interpretation of data - Sipahi, Simon, Fang.
Drafting of the manuscript - Sipahi, Chou, Hyden.
Critical revision of the manuscript - Sipahi, Chou, Hyden, Rowland, Simon, Fang.
Study supervision - Sipahi, Simon, Fang.
Other Contributors: None.
Financial and material support: None.
Potential Financial Conflicts of Interest:
Dr.
References (32)
- et al.
Cardiac resynchronization therapy in patients with right bundle branch block: analysis of pooled data from the MIRACLE and Contak CD trials
Heart Rhythm
(2005) - et al.
Usefulness of baseline electrocardiographic QRS complex pattern to predict response to cardiac resynchronization
Am J Cardiol
(2009) - et al.
Upgrade and de novo cardiac resynchronization therapy: impact of paced or intrinsic QRS morphology on outcomes and survival
Heart Rhythm
(2009) - et al.
Cardiac resynchronization therapy in patients with left ventricular systolic dysfunction and right bundle branch block: a systematic review
Heart Rhythm
(2011) - et al.
Diminished left ventricular dyssynchrony and impact of resynchronization in failing hearts with right versus left bundle branch block
J Am Coll Cardiol
(2007) Left ventricular conduction delays and relation to QRS configuration in patients with left ventricular dysfunction
Am J Cardiol
(2009)- et al.
Defining left bundle branch block in the era of cardiac resynchronization therapy
Am J Cardiol
(2011) - et al.
Heart failure: diagnosis and evaluation
- et al.
Cardiac resynchronization and death from progressive heart failure: a meta-analysis of randomized controlled trials
JAMA
(2003) - et al.
Cardiac resynchronization therapy for patients with left ventricular systolic dysfunction: a systematic review
JAMA
(2007)
Executive summary: HFSA 2006 Comprehensive Heart Failure Practice Guideline
J Card Fail
ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices): developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons
Circulation
ACC/AHA 2005 Guideline Update for the Diagnosis and Management of Chronic Heart Failure in the Adult: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Update the 2001 Guidelines for the Evaluation and Management of Heart Failure): developed in collaboration with the American College of Chest Physicians and the International Society for Heart and Lung Transplantation: endorsed by the Heart Rhythm Society
Circulation
ESC guidelines for the diagnosis and treatment of acute and chronic heart failure 2008: the Task Force for the diagnosis and treatment of acute and chronic heart failure 2008 of the European Society of Cardiology. Developed in collaboration with the Heart Failure Association of the ESC (HFA) and endorsed by the European Society of Intensive Care Medicine (ESICM)
Eur J Heart Fail
Power Analysis for Meta-Analysis
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