Early Cardiac Resynchronization Therapy (CRT) improves the outcome in Heart Failure (HF) patients with Left Bundle Branch Block (LBBB) Un precoce trattamento di resincronizzazione cardiaca (CRT) migliora la prognosi in pazienti con scompenso cardiaco e blocco di branca sinistro

sed from 97 + 37 ml/m2 and 126 + 38 ml/m2 to 61 + 34 ml/m2 and 93 + 37 ml/m2 respectively, but did not significantly reduced nor iESV neither iEDV in non responders that passed from 158 + 44 ml/m2 and 196 + 43 ml/m2 to 152 + 45 ml/m2 and to 184 + 44 ml/m2 respectively [3]. In responders the favourable effects of CRT are obtained within 2 months and are stable at least over a period of 6 months [8], but, possibly far longer. Consequently the determinants of CRT outcome are also the determinants of a further clinical course. In subjects with moderate left ventricular enlargement (iEDV 142 ml/m2) no significant functional improvements are obtained by CRT with consequent poor prognosis [6]. In our series all the patients that developed hard events (death or acute heart failure requiring hospitalization) over a two year follow-up had a pre-CRT LVEF no higher than 0.21 with no significant changes after CRT. In a three year survival study [6] on a relatively small series of patients (mean age 74 years) we observed that the subjects died for a worsening heart failure, had pre-CRT iESV volumes > 194 ml/m2. A very important left ventricular enlargement probably accounts for the nearly 30% of patients that do not take advantage from CRT [1, 7]. In the consideration that CRT is usually effective only in subjects with a moderate left ventricular enlargement and without an extremely depressed LVEF, we