Left branch bundle block may present as an isolated entity, even in normal hearts, in which apparently it does not impair the left ventricular function importantly. Studies in LBBB created by the implant of a right ventricular pacemeker, have shown deleterious effects on left ventricle systolic and diastolic functions associated sometimes with presence of mitral valve regurgitation. Paradoxical interventricular septal motion that follows the LBBB cause an additional impairment of left ventricular function and is in general present in patients with cardiomyopathy and congestive heart failure, with poor prognosis. In 1994 studying patients with cardiomyopathy Cazeau demonstrated that the use of four chamber pacing can increase cardiac output and decrease pulmonary capillary wedge pressures. Stimulated by this work, we decided to investigate the possibility of stimulation of the left ventricle apex alone, after sensing the P wave by the use of a dual-chamber pacemaker in patients with LBBB and paradoxical septal movement, aiming at the synchronization of interventricular septal contraction. This procedure was done in three patients and before hospital discharge they were submitted to echocardiographic studies with the pacemaker turned on and scintigraphy off to analyze the ejection fraction and the septal movement. In the first case the EF increased from 17 to 25%; in the second from 13 to 30% and in the third from 13 to 27%. The paradoxical movement disappeared in two cases and was classified as mild (+/+4+) in the first case. The functional class and mitral regurgitation were not included in this study because all three patients had combined procedures which could induce a false-positive improvement. Although this is a small number of cases, we believe that the procedure is promising for the treatment of patients with congestive heart failure, cardiomyopathy, left bundle branch block and paradoxical septal movement and it might be a future indication for the treatment of LBBB, before the deterioration of the left ventricle happens changing the quality of life and survival of these patients.
Pacemaker; Cardiomyopathy; Heart block; Heart septum; Heart ventricle
