Differentiating the Origin of Outflow Tract Premature Ventricular Complexes using the QRS-Right Ventricular Apex Interval

Abstract

remature ventricular contractions (PVCs) are the most common arrhythmia in structurally normal heart which is usually asymptomatic in most cases, however in some cases it may cause symptoms as palpitations, chest pain and syncope. For the treatment of PVCs, it is important to consider underlying heart disease, the frequency of the PVCs and severity of symptoms. Radiofrequency catheter ablation is indicated for treatment of symptomatic patients with PVCs if pharmacological therapy is proved to be ineffective or not tolerated. The Right Ventricular Outflow Tract (RVOT) is most common origin for PVCs in structurally normal heart while 10% of PVCs arise from Left Ventricular Outflow Tract (LVOT), the Electrocardiogram (ECG) is simplest, most used tool to localize and differentiate the origin of PVCs pre-procedural in Radiofrequency catheter ablation (RFCA), Although sometimes ECG doesn't allow accurate differentiation of the origin of PVCs such problem leads to prolonged time of (RFCA) or even failure of the procedure. The objectives of this work were to study the relation between the QRS-RVA interval and the origin of outflow tract PVCs, to differentiate between RVOT and LVOT origin of PVCs.