This study in agreement with previously published series,showed that permanent biventricular pacing improves subjective and objective parameters in patients with sever congestive heart failure.The new data and consistent with our hypothesis suggest that leftventricular pacing alone achieves the same goals. However if thisshort term similarity persists with long-term follow up, a cardiacresynchronization therapy system with only left ventricularstimulation might be useful but our ability to prove that was limited by a small sample size.