title: The proarrhythmic effect of cardiac resynchronization therapy: an issue that should be borne in mind.
abstract: The demonstrated benefits of cardiac resynchronization therapy (CRT) in reducing mortality and hospitalizations for heart failure, improving NYHA functional class and inducing reverse remodeling have led to its increasing use in clinical practice. However, its potential contribution to complex ventricular arrhythmias is controversial.We present the case of a female patient with valvular heart failure and severe systolic dysfunction, in NYHA class III and under optimal medical therapy, without previous documented ventricular arrhythmias. After implantation of a CRT defibrillator, she suffered an arrhythmic storm with multiple episodes of monomorphic ventricular tachycardia (VT), requiring 12 shocks. Subsequently, a pattern of ventricular bigeminy was observed, as well as reproducible VT runs induced by biventricular pacing. Since no other vein of the coronary sinus system was accessible, it was decided to implant an epicardial lead to stimulate the left ventricle, positioned in the left ventricular mid-lateral wall. No arrhythmias were detected in the following six months. This case highlights the possible proarrhythmic effect of biventricular pacing with a left ventricular lead positioned in the coronary sinus venous system.
authors.affiliation: Serviço de Cardiologia, Hospital de Santarém, Santarém, Portugal. Electronic address: ncabanelas@gmail.com.
authors.forename: Nuno
authors.initials: N
authors.lastname: Cabanelas
authors.affiliation: Serviço de Cardiologia, Hospital de Santa Marta, Centro Hospitalar de Lisboa Central, Lisboa, Portugal.
authors.forename: Mário
authors.initials: M
authors.lastname: Oliveira
authors.affiliation: Serviço de Cardiologia, Hospital de Santa Marta, Centro Hospitalar de Lisboa Central, Lisboa, Portugal.
authors.forename: Manuel
authors.initials: M
authors.lastname: Nogueira da Silva
authors.affiliation: Serviço de Cardiologia, Hospital de Santa Marta, Centro Hospitalar de Lisboa Central, Lisboa, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Cunha
authors.affiliation: Serviço de Cardiologia, Hospital de Santa Marta, Centro Hospitalar de Lisboa Central, Lisboa, Portugal.
authors.forename: Bruno
authors.initials: B
authors.lastname: Valente
authors.affiliation: Serviço de Cardiologia, Hospital de Santa Marta, Centro Hospitalar de Lisboa Central, Lisboa, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Lousinha
authors.affiliation: Serviço de Cardiologia, Hospital de Santa Marta, Centro Hospitalar de Lisboa Central, Lisboa, Portugal.
authors.forename: Sofia
authors.initials: S
authors.lastname: Santos
authors.affiliation: Serviço de Cardiologia, Hospital de Santa Marta, Centro Hospitalar de Lisboa Central, Lisboa, Portugal.
authors.forename: Luísa
authors.initials: L
authors.lastname: Branco
authors.affiliation: Serviço de Cardiologia, Hospital de Santa Marta, Centro Hospitalar de Lisboa Central, Lisboa, Portugal.
authors.forename: Rui
authors.initials: R
authors.lastname: Ferreira
mesh_terms: D058406:Cardiac Resynchronization Therapy / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008875:Middle Aged; D017180:Tachycardia, Ventricular / Q000209:etiology*
keywords: Cardiac resynchronization; Epicardial pacing; Heterogeneidade da repolarização; Pacing epicárdico; Repolarization heterogeneity; Ressincronização cardíaca