摘要
Background: Idiopathic ventricular tachycardia(VT) often originates from the r ight ventricular outflow tract (RVOT), but foci deep to the endocardium, in the epicardium, or in the left ventricle are not uncommon. Although these extra-RVO T foci can be targeted with ablation, risks involved are higher and success rate s lower. Simple electrocardiographic(ECG) criteria allowing(1) discrimination of RVOT foci from extra-RVOT foci and(2) assessment of the chance of success of a right heart ablation procedure are desirable. Methods: Twenty-five consecutive patients referred for radiofrequency(RF) ablation of idiopathic VT or severely symptomatic idiopathic ventricular premature contractions were included. Localiz ation of VT origin and success rates of VT ablation in the RVOT were analyzed ac cording to the ECG pattern. Results: The analysis of the R wave in V2 was the st rongest single predictor of whether the VT had an RVOT or an extra-RVOT origin. An R wave amplitude ≥30%of the QRS amplitude designated the VT focus in the R VOT with positive and negative predictive values of 95 and 100%, respectively. Analysis of R wave duration in V2 had similar predictive values, whereas the R/S transitionzone in precordial leads had slightly lower predictive values. Sevent een of 20 arrhythmias(85%) with an R wave amplitude ≥30%of the QRS amplitude in V2 could be successfully abolished by an exclusively right heart procedure. C onclusions: The analysis of ECG pattern makes it possible to guide the manageme nt of patients with idiopathic VT in predicting the arrhythmias that can be safely targeted with RF ablation from the RVOT with high success rates. Copyright.
Background: Idiopathic ventricular tachycardia(VT) often originates from the r ight ventricular outflow tract (RVOT), but foci deep to the endocardium, in the epicardium, or in the left ventricle are not uncommon. Although these extra-RVO T foci can be targeted with ablation, risks involved are higher and success rate s lower. Simple electrocardiographic(ECG) criteria allowing(1) discrimination of RVOT foci from extra-RVOT foci and(2) assessment of the chance of success of a right heart ablation procedure are desirable. Methods: Twenty-five consecutive patients referred for radiofrequency(RF) ablation of idiopathic VT or severely symptomatic idiopathic ventricular premature contractions were included. Localiz ation of VT origin and success rates of VT ablation in the RVOT were analyzed ac cording to the ECG pattern. Results: The analysis of the R wave in V2 was the st rongest single predictor of whether the VT had an RVOT or an extra-RVOT origin. An R wave amplitude ≥30%of the QRS amplitude designated the VT focus in the R VOT with positive and negative predictive values of 95 and 100%, respectively. Analysis of R wave duration in V2 had similar predictive values, whereas the R/S transitionzone in precordial leads had slightly lower predictive values. Sevent een of 20 arrhythmias(85%) with an R wave amplitude ≥30%of the QRS amplitude in V2 could be successfully abolished by an exclusively right heart procedure. C onclusions: The analysis of ECG pattern makes it possible to guide the manageme nt of patients with idiopathic VT in predicting the arrhythmias that can be safely targeted with RF ablation from the RVOT with high success rates. Copyright.
