[Pacemaker in therapy of heart failure--biventricular stimulation]

The management of congestive heart failure remains a therapeutic challenge despite recent advances in drug therapy, including ACE inhibitors, beta blockade and spironolacton treatment. Patients affected with the disease still have a restricted quality of life and a poor prognosis in the long run. Epidemiologically, the incidence and prevalence are increasing due to improved survival from both coronary artery disease and arterial hypertension. A subgroup of patients presents with marked prolongation of the QRS-complex in the surface ECG, mostly with a left bundle branch block pattern. This acts as a marker for interventricular conduction abnormality and specifically indicates a reduced left ventricular systolic function. Biventricular pacing tries to resynchronize the abnormal activation pattern by actively influencing diastolic filling and systolic function. The mechanisms involved are supposed to be restoration of left ventricular septal mechanical synchrony, reduction in presystolic mitral regurgitation and optimization of diastolic function with the maximization of diastolic filling time. In this article the current role and future directions of biventricular pacing are discussed.