Catheter ablation of ventricular arrhythmias originating from the sinus of valsalva: the reminder from the mapping or ablation in the lower right ventricular outflow tract

Background Ventricular arrhythmias (VAs) originating from ventricular outflow tracts can possess a high similarity of QRS configuration resulting in an inaccurate localization, while the reminder of mapping or ablation in the lower right ventricular outflow tract (RVOT) commonly provide the preferred transformation strategy. Methods We retrospectively analyzed the total of 958 patients who were referred for radiofrequency (RF) ablation of VAs in our center. VAs with the sinus of valsalva (SoV) origins were enrolled. Results A total of 120 consecutive patients (mean age 45.0 ± 15.5 years) undergoing the ablation of VAs arising from the left-sided ventricular outflow tracts were included, with 55 (45.8%) female. All patients had a QRS morphology of the LBBB pattern and an inferior axis, with the mean earliest ventricular activation (EVA) of target site of 34.9 ± 8.8ms. 37 (30.8%), 60 (50.0%), and 23 (19.2%) patients obtained the successful RF ablation at the right sinus cusp (RCC), left sinus cusp (LCC), and the commissure of RCC and LCC (R-LCC), respectively. 62 (51.7%) target sites of SoV could record a high-frequency potential. Moreover, 25 (20.8%) patients were continuously recorded an early ventricular activation in the lower RVOT and achieved the elimination of VAs in SoV. Conclusions VAs originating from the SoV could show a low specificity of QRS morphology mimicking the RVOT-like ECG feature. An early ventricular activation mapped in the lower RVOT or RF ablation with poor response likely demonstrated the VAs originating from the SoV, especially the RCC.