Cardiac Resynchronization Therapy for mild to moderate heart failure - The New England Journal of Medicine - 2010

Brief Summary:

Among patients with heart failure (NYHA class II or III), widened QRS and left ventricular ejection fraction ≤30%, the addition of CRT to an ICD reduces the mortality and morbidity but increased the rate of adverse events, as compared to ICD alone.

Reference: http://www.ncbi.nlm.nih.gov/pubmed/21073365