Peer reviewed article Cardiac resynchronisation therapy in chronic heart failure

Cardiac resynchronisation therapy (CRT) has emerged as a treatment option for patients with se-vere, drug-refractory heart failure and signs of in-traventricular dyssynchrony. In clinical trials CRT reduced the overall mortality, improved symp-toms, exercise tolerance, and left ventricular func-tion, as compared with optimised medical therapy alone. One of the challenging fields in patient se-lection for CRT is to identify the 20–30 % of heart failure patients with bundle branch block that will not respond to this novel therapy. Other fields of uncertainty, such as CRT in patients with atrial fib-rillation or chronic right ventricular stimulation as well as the role of a back-up defibrillator will be discussed. Key words: heart failure; cardiac resynchronization therapy; biventricular pacing; QRS duration Major progress has been made in the pharma-cological management of patients with heart failure. The introduction and widespread use of angiotensin converting enzyme inhibitors, an-giotensin II-receptor blockers, beta-blocking agents, and spironolactone improved mortality and morbidity in this population [1–4]. However, trials of new agents, such as endothelin antago-nists, vasopeptidase inhibitors, and soluble tumour necrosis factor a-antagonists, did not show further survival benefits. Cardiac resynchronisation ther-apy (CRT) has emerged as a highly effective treat-ment option in a subset of patients with marked intraventricular dyssynchrony. Eight randomised trials with more than 4000 patients have been com-pleted and give evidence for the effectiveness o