[Cardiac pacing in obstructive hypertrophic cardiomyopathies].

Up until recently, the first-line treatment of obstructive hypertrophic cardiomyopathy was pharmacological and surgical in refractory cases. However, the immediate beneficial effect of a cardiac pacing on infra-aortic obstruction has been known for many years. The development of sophisticated two-chamber pacemakers and their use in patients with obstructive hypertrophic cardiomyopathy has confirmed their beneficial effect both in terms of haemodynamic and clinical parameters. There appears to be many reasons for this advantageous effect and only some of them have been elucidated, including alteration of the activation sequence of the left ventricle secondary to apical ectopic electrical activation and reduction of the contact time of the mitral valve with the proximal septum and, in the long term, ventricular remodelling secondary to release of the outflow obstruction. The increasing number of publications reporting a beneficial effect of two-chamber pacemakers in these patients justifies consideration of this approach in all patients refractory to drug therapy.