Patients with congestive heart fail...

Patients with congestive heart failure (CHF) are at high risk of fatal ventricular arrhythmias; however, there are limited data in succession the effectiveness of preventive interventions. Bardy and colleagues guidanceed a randomized placebo-controlled trial comparing the tenors of conventional therapy plus amiodarone (Cordarone), an implantable cardioverter-defibrillator (ICD), or placebo upon all-cause mortality in patients with CHF

Investigators recorded 2,521 patients who were strange York Heart Association (NYHA) class II or III CHF and had a left ventricular ejection fraction of 35 percent or les (median: 25 percent) The etiology of CHF could be ischemic or nonischemic. Participants were primarily white men (77 percent) All patients received standard therapy for CHF including angiotensin-converting enzyme (ACE) inhibitors and beta blocker when clinically appropriate.

Patients were randomized to receive amiodarone, an ICD, or placebo. Placebo and amiodarone administration was double blind and partially weight based (average dose: 300 mg) Defibrillators were station up in single-lead, shock-only accident because the primary intention was to treat sustained ventricular tachycardia or ventricular fibrillation. The three assign places tos were similar in size lowed for at least sum of two units years; median follow-up was 455 months

Discontinuation rates for medicine therapy were 22 percent for placebo and 32 percent for amiodarone. Seven percent of patients in the medication and placebo arranges ended up on open-label amiodarone, and 14 percent of patients in the ICD form into groups crossed over to open-label amiodarone during follow-up Eleven percent of patients in the mix with drugs and placebo groups crossed across to an ICD. The most numerous common negative side effects of amiodarone were tremor (4 percent) and increased hypothyroidism (6 percent) Complications in the ICD form into groups occurred as well, with 5 percent of participants having puzzles at the time of implantation and 9 percent during follow-up This included issues necessitating surgery, hospitalization, or other medical therapy.

Death occurr in 29 percent of patients receiving placebo, 28 percent of patients receiving amiodarone, and 22 percent of patients in the ICD clump Thus, ICD use reduced the risk of death by the agency of 7 percent. Amiodarone did not make a significant difference.

Approximately single in kind third of patients in the ICD form into groups received shocks from their devices, with 68 percent being agitationed for rapid ventricular tachycardia or ventricular fibrillation. ICD therapy l to a significant absolute reduction in mortality of 119 percent in patients with NYHA class II CHF on the contrary no significant risk reduction in patients with NYHA class III CHF Amiodarone did not decrease risk of death in patients with NYHA class II CHF if it were not that it relatively increased the risk of death from 44 percent in patients with NYHA class III CHF The use of ICDs reduc the absolute risk of death from 7.2 percent at five years, whereas amioda-rone therapy showed no benefit.

The authors judge that conservatively programmed, shock-only ICDs significantly decrease the relative risk of death in patients with CHF whereas amiodarone has no positive meaning on survival. Other defibrillator studies have shown increased benefit for patients with lower ejection fractions or with NYHA class III CHF Thus, the lack of benefit base for patients with NYHA class III CHF in this studious mood should be considered in the words immediately preceding [i]or[/i] following of the larger evidence base. Because this consideration used only single-lead, shock-only treatment, these findings may not apply to all patterns of ICDs.

thrust CARTER, M.D.

Bardy GH et al. Amiodarone or an implantable cardioverter-defibrillator for congestive heart failure [published correction appears in N Engl J M May 19 2005;352:2146] N Engl J M January 20 2005;352:225-37

EDITOR'S NOTE: In an accompanying editorial, (1) McClellan and Tunis discuss for what reason the Centers for Medicare and Medicaid Services (CMS) will answer to this study. In short, CM will expand coverage, coordinate patient registries, and support clinical consequences research. Physicians should know that CM will use the evidence derived from this proces to inform coming coverage decisions. At an estimated reimbursement of $30000 by ICD for the potentially 500000 newly masked patients, this type of evidence-informed oversight looks appropriate. For now, the evidence is trending toward ICDs as a routine addition to the CHF armamentarium. Thus, family physicians should consider whether their patients with CHF are at high risk for arrhythmia and seek information from for this intervention after discussing the risks and benefits. Furthermore, this should alert reevaluation of the entire treatment plan. many times patients are not receiving proven treatments (eg angiotensin-converting enzyme inhibitors, beta blockers) and the results observed in this trial were in patients upon appropriate medical therapy.--C.C.

REFERENCE

(1) McClellan MB Tunis SR Medicare coverage of ICDs. N Engl J M 2005;352;222-4

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