%0 Journal Article
%T QRS Complex Enlargement as a Predictor of Ventricular Arrhythmias in Patients Affected by Surgically Treated Tetralogy of Fallot: A Comprehensive Literature Review and Historical Overview
%A Pier Paolo Bassareo
%A Giuseppe Mercuro
%J ISRN Cardiology
%D 2013
%R 10.1155/2013/782508
%X Tetralogy of Fallot (TOF) is a congenital heart disease frequently treated by surgical repair to relieve symptoms and improve survival. However, despite the performing of an optimal surgical repair, TOF patients are at times characterized by a poor long-term survival rate, likely due to cardiac causes such as ventricular arrhythmias, with subsequent sudden death. In the 80s it was irrefutably demonstrated that QRS prolongation ¡İ180£¿msec at basal electrocardiogram is a strong predictor for refining risk stratification for ventricular tachycardia in these patients. The aim of this research was to undertake a review of all studies conducted to assess the impact of QRS duration on the development of life-threatening ventricular arrhythmias in repaired TOF subjects. 1. Introduction Tetralogy of Fallot (TOF) is a congenital heart disease characterized by a large ventricular septal defect, an aorta that overrides the left and right ventricles, obstruction of the right ventricular outflow tract, and right ventricle hypertrophy. Surgical repair of this pathology is recommended to relieve symptoms and to improve survival. However, despite the performing of an optimal surgical repair, TOF patients may feature a poor long-term survival rate, likely due to cardiac causes such as ventricular arrhythmias. The pathogenesis of this kind of tachycardia, thought to account for the majority of cases of sudden unexpected death in operated TOF patients, remains to be fully elucidated [1¨C3]. Consequently, life-threatening ventricular arrhythmia and sudden death continue to represent serious late complications following TOF repair. Several risk factors have been identified in predicting TOF patients at major risk of sudden death: severity of initial presentation of the disease, preoperative polycythemia, delay in surgical correction of the lesion, elevated left ventricular end-diastolic pressure, initial Blalock-Taussig shunt placement, ventriculotomy, and ventricular arrhythmias [4, 5]. The aim of this work was to undertake a paper of all studies conducted to assess the impact of QRS duration on the development of life-threatening ventricular arrhythmias in repaired TOF subjects. QRS complex corresponds to the depolarization of the right and left ventricles. Duration of the complex may be calculated simply by means of an electrocardiogram, an easy, economical, and noninvasive investigation that is usually readily available in an outpatient setting. This paper should provide help to primary care practitioners in identifying TOF patients at increased risk of developing
%U http://www.hindawi.com/journals/isrn.cardiology/2013/782508/