Fish oil supplementation and risk of ventricular tachycardia and ventricular fibrillation in patients with implantable defibrillators: a randomized controlled trial.

CONTEXT: Clinical studies of omega-3 polyunsaturated fatty acids (PUFAs) have shown a reduction in sudden cardiac death, suggesting that omega-3 PUFAs may have antiarrhythmic effects. OBJECTIVE: To determine whether omega-3 PUFAs have beneficial antiarrhythmic effects in patients with a history of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF). DESIGN AND SETTING: Randomized, double-blind, placebo-controlled trial performed at 6 US medical centers with enrollment from February 1999 until January 2003. PATIENTS: Two hundred patients with an implantable cardioverter defibrillator (ICD) and a recent episode of sustained VT or VF. INTERVENTION: Patients were randomly assigned to receive fish oil, 1.8 g/d, 72% omega-3 PUFAs, or placebo and were followed up for a median of 718 days (range, 20-828 days). MAIN OUTCOME MEASURES: Time to first episode of ICD treatment for VT/VF, changes in red blood cell concentrations of omega-3 PUFAs, frequency of recurrent VT/VF events, and predetermined subgroup analyses. RESULTS: Patients randomized to receive fish oil had an increase in the mean percentage of omega-3 PUFAs in red blood cell membranes from 4.7% to 8.3% (P<.001), with no change observed in patients receiving placebo. At 6, 12, and 24 months, 46% (SE, 5%), 51% (5%), and 65% (5%) of patients randomized to receive fish oil had ICD therapy for VT/VF compared with 36% (5%), 41% (5%), and 59% (5%) for patients randomized to receive placebo (P = .19). In the subset of 133 patients whose qualifying arrhythmia was VT, 61% (SE, 6%), 66% (6%), and 79% (6%) of patients in the fish oil group had VT/VF at 6, 12, and 24 months compared with 37% (6%), 43% (6%), and 65% (6%) of patients in the control group (P = .007). Recurrent VT/VF events were more common in patients randomized to receive fish oil (P<.001). CONCLUSION: Among patients with a recent episode of sustained ventricular arrhythmia and an ICD, fish oil supplementation does not reduce the risk of VT/VF and may be proarrhythmic in some patients.

Cost-effectiveness of the implantable cardioverter-defibrillator versus antiarrhythmic drugs in survivors of serious ventricular tachyarrhythmias: results of the Antiarrhythmics Versus Implantable Defibrillators (AVID) economic analysis substudy.

BACKGROUND: The implantable cardioverter-defibrillator (ICD) is an effective but expensive device. We used prospectively collected data from a large randomized clinical trial of secondary prevention of life-threatening ventricular arrhythmias to determine the cost-effectiveness of the ICD compared with antiarrhythmic drug (AAD) therapy, largely with amiodarone. METHODS AND RESULTS: Charges for initial and repeat hospitalizations, emergency room, and day surgery stays and the costs of antiarrhythmic drugs were collected on 1008 patients. Detailed records of all other medical encounters and expenses were collected on a subgroup of 237 patients. Regression models were then created to attribute these expenses to the rest of the patients. Charges were converted to 1997 costs using standard methods. Costs and life years were discounted at 3% per year. Three-year survival data from the Antiarrhythmics Versus Implantable Defibrillators trail were used to calculate the base-case cost-effectiveness (C/E) ratio. Six-year, twenty-year, and lifetime C/E ratios were also estimated. At 3 years, total costs were $71 421 for a patient taking AADs and $85 522 for a patient using an ICD, and the ICD provided a 0.21-year survival benefit over AAD treatment. The base-case C/E ratio was thus $66 677 per year of life saved by the ICD compared with AAD therapy (95% CI, $30 761 to $154 768). Six- and 20-year C/E ratios remained stable between $68 000 and $80 000 per year of life saved. CONCLUSIONS: The ICD is moderately cost-effective for secondary prevention of life-threatening ventricular arrhythmias, as judged from prospectively collected data in a randomized clinical trial.