SYNCHRO. Evaluation of the Forecasts Parameters of Real Time-three-dimensional Doppler Echocardiography in Selecting Patients With Chronic Heart Failure for Cardiac Resynchronisation Therapy

Inclusion Criteria: * Both gender * Age\>18 years * Patients in functional class NYHA III or IV * Patient with ejection fraction \<or=150msec or with QRS between 120 and 149 msec but with echocardiographic evidences for cardiac dyssynchrony, such as those retained in the CARE-HF trial, e.g.two from the three following criterions :-Aortic pre-ejection delay\>140msec * Interventricular mechanical delay \>40msec * Delayed activation of the left ventricular postero-lateral wall * Patient under optimal treatment for chronic heart failure for at least one month before inclusion * Written informed consentement Exclusion Criteria: * Patient with atrial fibrillation * Absence of echogenicity * Patient with an indication for pacemaker implantation * Patient suffering from arterial pressure disorders, with systolic pressure greater than 170 or lower than 80 mmHg * Major cardiovascular event within 6 weeks before inclusion * Patient in the exclusion period of any other clinical trial * Patient without social insurance policy * Drug or alcohol addiction * Any psychological disorder * Pregnant women * Patient with a transplanted organ * HIV positive serology at inclusion