Cardiac resynchronisation therapy by biventricular pacing in severe heart failure

: Biventricular pacing with one pacemaker lead introduced via the coronary sinus to a coronary vein and one pacemaker lead located endocardially at the apex of the right ventricle is used for cardiac resynchronisation therapy in patients with severe heart failure and bundle branch block indicating asynchronous contraction of the left ventricle. Randomised multicentre studies show significant improvement of functional capacity, quality of life and left ventricular systolic function in patients with severe heart failure and bundle branch block. In one study, a significant reduction of 77% of hospitalisation days has been demonstrated. Combined implantable biventricular pacing and cardioverter defibrillator units resulted in a 43% reduction of mortality in patients with severe heart failure compared to optimal pharmacological treatment only. Our studies show that selection of patients for cardiac resynchronisation therapy by using echocardiographic methods in addition to ECG may help to avoid implanting pacemakers in patients who will not respond to the therapy. In our studies resynchronisation of the contraction of the left ventricle was demonstrated by using colour tissue Doppler measurements. The mechanisms for the haemodynamic benefit of cardiac resynchronization therapy are discussed. This relatively new therapy represents a significant progress in the treatment of patients with severe heart failure and asynchronous left ventricular contraction refractory to treatment.