1. Home>
2. Specialties>
3. Cardiology>
4. Clinical Practice Guideline Watch

Guidelines: Ventricular Arrhythmias and Prevention of Sudden Cardiac Death

Joint recommendations from three major cardiology societies

Sponsoring Organizations: American College of Cardiology, American Heart Association, European Society of Cardiology

Background and Purpose: The evidence base for managing ventricular arrhythmias and preventing sudden cardiac death (SCD) has been interpreted differently in different countries. An international committee has now synthesized the evidence, where possible, and published a set of guidelines jointly endorsed by the ACC, AHA, and ESC.

Below are key points of the recommendations for implantable cardioverter-defibrillator (ICD) therapy, the area with the most substantial changes. Previous recommendations for prophylactic ICD therapy based on left-ventricular ejection fraction (LVEF) were inconsistent for several reasons: clinical trials used different LVEF thresholds for enrollment, average LVEFs in the trials were sometimes much lower than enrollment cutoff values, and subgroup analyses sometimes yielded inconsistent results. The current recommendations attempt to reconcile inconsistencies, although LVEF thresholds still are represented with ranges rather than discrete values. Class I recommendations reflect consistent evidence and/or consensus opinion; class IIa recommendations reflect some conflict among evidence or opinion, with the weight in favor of usefulness or efficacy.

Key Points:
1. New class I recommendations for ICD primary-prevention therapy in certain subsets of patients with NYHA class II or III heart failure on optimal medical therapy:

• those with LV dysfunction due to prior MI (if the MI occurred 40 days previously) and an LVEF 30% to 40% (reflecting a range in the evidence base)
  
• those with nonischemic heart disease with an LVEF 30% to 35% (reflecting a range in the evidence base)
  

2. A class IIa recommendation for ICD primary-prevention therapy in patients with hypertrophic cardiomyopathy who have at least one major risk factor for SCD

3. A class IIa recommendation for ICD primary-prevention therapy in patients with extensive arrhythmogenic right-ventricular cardiomyopathy (ARVC), including those with LV involvement, history of syncope, or other affected family members

4. ICDs should be considered only in patients who are on optimal medical therapy and are expected to survive for more than 1 year with good functional status.

Comment: These are only a few of the important points in these internationally developed guidelines. They also include specific recommendations for genetic analysis and for treatment in ARVC, long-QT syndrome, and Brugada syndrome. And, of course, there are recommendations for when to use diagnostic tests (e.g., ECG, electrophysiology, microvolt T-wave alternans), catheter ablation, and antiarrhythmic drug therapy. For U.S. clinicians, most recommendations are consistent with coverage by Medicare. However, there are exceptions; for example, Medicare does not cover ICD therapy for a patient whose LVEF is >35%.

Overall, these guidelines are a well-synthesized reference, and they clarify points of contention among different previous guidelines. They also identify where consensus does not yet exist and where science can answer lingering questions. The executive summary is cited below, but clinicians will also find value in referring to the complete guidelines and the pocket guidelines.

— Mark D. Carlson, MD

Published in Journal Watch Cardiology October 18, 2006

Citation(s):

Zipes DP et al. ACC/AHA/ESC 2006 guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death — Executive summary: A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Develop Guidelines for the Management of Patients with Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death). J Am Coll Cardiol 2006 Sep 5; 48:1064-108.

• Original article (Subscription may be required)
• Medline abstract (Free)

2011 Top Stories