"Prophylactic Implantation of a Defibrillator in Patients with Myocardial Infarction and Reduced Ejection Fraction". The New England Journal of Medicine. 2002. 346(12):877-883.
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Contents 1 Clinical Question 2 Bottom Line 3 Major Points 4 Guidelines 5 Design 6 Population 6.1 Inclusion Criteria 6.2 Exclusion Criteria 6.3 Baseline Characteristics 7 Interventions 8 Outcomes 8.1 Primary Outcome 9 Criticisms 10 Funding 11 Further Reading
Does prophylactic implantation of a defibrillator improve survival among patients with a prior myocardial infarction and reduced left ventricular ejection fraction?
Prophylactic implantation of a defibrillator in patients with prior myocardial infarction and a left ventricular ejection fraction of 0.30 or less improves survival.
Implantable defibrillators have been known to improve survival in high-risk patients, but previous studies required invasive electrophysiological testing. The Multicenter Automatic Defibrillator Implantation Trial II (MADIT-II) sought to evaluate the benefit of prophylactic defibrillators without the need for such testing in patients with a prior myocardial infarction and advanced left ventricular dysfunction.
Patients who fit the MADIT-II profile (prior MI and EF ≤30%) are generally recommended to consider prophylactic implantation of a defibrillator.
- Multicenter, randomized controlled trial - N=1232 patients with prior MI and ejection fraction ≤0.30 - Intervention: Implantable defibrillator (n=742) - Control: Conventional medical therapy (n=490) - Primary outcome: Death from any cause - Follow-up: Average of 20 months
Inclusion Criteria - Prior myocardial infarction - Left ventricular ejection fraction ≤0.30
Exclusion Criteria - Contraindications for defibrillator - Recent MI or revascularization - Advanced non-cardiac diseases
Baseline Characteristics - Similar between groups - Medication use at last follow-up was also comparable
- Transvenous defibrillator implantation in the intervention group - Standard medical treatment in the control group
Primary Outcome - 19.8% mortality in conventional therapy group - 14.2% mortality in defibrillator group - Hazard ratio for death: 0.69 (95% CI, 0.51 to 0.93; P=0.016)
- The incidence of heart failure requiring hospitalization was higher in the defibrillator group. - The cost and resource implications of widespread prophylactic implantation are substantial.
The study was supported by a research grant from Guidant to the University of Rochester School of Medicine and Dentistry. Some authors disclosed financial relationships with Guidant.
The trial publication and relevant additional literature involve advancements in the field of cardiac electrophysiology and criteria for defibrillator implantation post-MI.