Use of Cardiac Resynchronisation Therapy – Change of Clinical Settings

Abstract

Heart failure (HF) is a growing and major health burden in western countries. The prevalence of HF is estimated at 1-2 % in the western world, and the incidence approaches 5-10 per 1,000 persons per year. Cardiac resynchronisation therapy (CRT) has been shown in multiple studies to improve HF symptoms, quality of life and improve survivals. 2-6The two landmark studies, Comparison of Medical Therapy, Pacing and Defibrillation in Heart Failure (COMPANION) and Cardiac ResynchronizationHeart Failure (CARE-HF), established the clinical indications for CRT, which form the basis for consensus international guidelines. [5][6][7] These two trials randomised 2,333 patients in sinus rhythm (SR) with QRS prolongation on surface electrocardiogram (ECG) (≥120 ms), New York Heart Association (NYHA) functional class III and ambulatory class IV HF and a persistently reduced left ventricular ejection fraction (LVEF), despite optimal medical treatment. The trials showed that CRT reduced the risk of death from any cause and hospital admission for worsening HF. 5,6 The effect of left ventricular reverse remodelling from CRT was sustained over time. York Heart Association (NYHA) class III or IV heart failure (HF) symptoms. Ongoing studies aim to expand the use of CRT in patients with asymptomatic or minimal symptoms left ventricular dysfunction. There have been studies that have shown benefit of CRT extended to this group of patients. There have also been different implications of the role of CRT in patients with atrial fibrillation (AF), patients with narrow QRS duration or with right bundle branch block (RBBB) on surface ECG, as well as patients with end-stage renal failure on dialysis therapy. This article aims to review the current body of evidence of expanding use of CRT in these populations.