Failure of cilostazol in the prevention of ventricular fibrillation in a patient with Brugada syndrome.

The ECG appearance in Brugada syndrome is caused by failure of the dome of the action potential to develop. Increased activity of the I(to) current in epicardial cells generates a transmural gradient with repolarization dispersion between the epicardium and the endocardium in the right ventricular wall, thus favoring the development of VF by a phase 2 reentry mechanism. The efficacy of cilostazol for the management of these arrhythmias has been reported. This drug is a phosphodiesterase inhibitor with positive chronotropic properties, thus blocking outward potassium currents I(to) in the myocardial tissue. We present a patient with Brugada syndrome with an implantable cardioverter defibrillator (ICD), who suffered multiple ICD discharges due to VF during therapy with this drug.

Implante de un cardiodesfibrilador bicameral vía vena cava superior izquierda persistente / Implant of a Dual-chamber Implantable Cardioverter Defibrillator through a Persistent Left Superior Vena Cava

La vena cava superior izquierda persistente (VCSIP) es la anomalía congénita venosa del tórax más frecuente. Se encuentra en el 0,3% de la población general y en el 5-10% de los pacientes con cardiopatías congénitas. Generalmente evoluciona en forma asintomática y no genera trastornos hemodinámicos, pero su reconocimiento es importante, ya que puede dificultar la introducción de catéteres para mediciones hemodinámicas, los implantes de marcapasos cardíacos (MCP) y de cardiodesfibriladores automáticos implantables (CDAI), especialmente cuando se utiliza la vía cefálica o la subclavia izquierda. En el caso clínico que se presenta se efectuó el implante de un CDAI bicameral vía VCSIP, descubierta durante el procedimiento. Asimismo, se muestran las características de esta variedad anatómica mediante tomografía cardíaca computarizada de 64 cortes (TCC64).

Persistent left superior vena cava (PLSVC) is the most common congenital defect in the thoracic venous system, with an incidence of 0.3% in the general population and of 5-10% in patients with congenital heart disease. This asymptomatic condition does not produce hemodynamic impairment; however, it should be recognized as its presence poses technical challenges in the introduction of catheters for hemodynamic measurements and for placement of pacemakers (PMs) and implantable cardioverter defibrillators (ICD) via the cephalic vein or the left suclavian vein. In the present case report we describe the implantation of a dual-chamber ICD through a PLSVC discovered during the procedure. In addition, images from cardiac 64-row multidetector computed tomography (64-row CT) show the anatomic features of this variety.