An electrocardiographic sign of idiopathic ventricular tachycardia ablatable from the distal great cardiac vein.

BackgroundIdiopathic ventricular arrhythmias (IVAs) can originate from the distal great cardiac vein (DGCV). However, inadequate distinction sometimes occurs when electrocardiographic (ECG) characteristics are used to distinguish ventricular arrhythmias (VAs) arising from the DGCV from those arising from the adjacent left ventricular endocardium (LV ENDO).ObjectiveThe purpose of this study was to identify distinct ECG features in patients with idiopathic IVAs originating from the DGCV.MethodsA total of 32 patients with IVAs originating from the DGCV were identified from a consecutive group of 874 patients undergoing IVAs ablation. Patients with IVAs from the DGCV were compared with a consecutively chosen series of 40 patients with IVAs in whom the site of origin was the adjacent LV ENDO.ResultsOf the 32 patients with IVAs arising from the DGCV, 13 had distinct ECG characteristics compared with the LV ENDO group. Notches in both the upstroke and downstroke of the R wave in lead III were found in all 13 patients. However, the characteristic ECG pattern in lead III was found in 1 of 40 patients in the LV ENDO group. The ECG characteristic of both early notch and late notches in lead III has sensitivity of 40.6%, specificity of 97.5%, negative predictive value of 67.2%, and positive predictive value of 92.9% to predict VAs arising from the DGCV.ConclusionThe distinct ECG characteristics of VAs originating from the DGCV can help differentiate from adjacent LV ENDO sites of origin.