Medtronic
 
 

Heart Failure

Potential Candidates for CRT

Randomized controlled trials,1,2 which have now included over 2,500 patients, have shown that about 70% of patients with NYHA class III/IV heart failure, a QRS duration > 130 ms, a left ventricular ejection fraction < 35%, and a left ventricular end-diastolic diameter > 55 mm respond favorably to CRT. Additional studies, including a large, multi-center trial to assess the potential of echo-based measures of dyssynchrony, are currently underway to help better identify those patients most likely to respond to CRT.

Indications for CRT:

  • Symptomatic despite stable, optimal medical therapy
  • NYHA class III-IV (moderate to severe) heart failure
  • Ventricular dyssynchrony demonstrated by QRS duration > 130 ms
  • Left ventricular ejection fraction < 35%

 

References
  1. Abraham W, Fisher W, Smith A, et al. Cardiac resynchronization in chronic heart failure. N Engl J Med. 2002; 346:1845-1853.
  2. Young J, Abraham W, Smith A, et. al. Combined cardiac resynchronization and implantable cardioverter defibrillation in advanced chronic heart failure. The MIRACLE ICD Trial. JAMA 2003; 289:2685-2694.

Additional Information