Is there a need for more than one left ventricular lead in some patients?

Cardiac resynchronization therapy (CRT) is an effective treatment of heart failure in selected patients. However, with conventional CRT, notable left ventricular (LV) reverse remodelling is achieved in only 60-70% of patients. This lack of effect of CRT might be due to incomplete resynchronization. In some patients, the paced activation front arising from a single LV electrode is unfavourable, possibly resulting in suboptimal resynchronization. Dual-site LV CRT has theoretical advantages in faster and more physiological LV activation. Some clinical evidence supports dual LV pacing. Nevertheless, a clear benefit of this pacing modality in patients chronically implanted is still unproved. A randomized study comparing single- and dual-site LV pacing, the Triple-Site Cardiac Resynchronization study of Patients with Heart Failure (TRUST CRT) is still ongoing.