Challenges in ablating ventricular arrhythmias originating from the left ventricular summit region

BACKGROUND: Radiofrequency catheter ablation of ventricular arrhythmias, originating from the left ventricular summit, is challenging due to epicardial localisation of the substrate, surrounded by coronary arteries. This paper highlights the successful elimination of LVOT summit ventricular arrhythmia which was ablated from the aortic cusp and aortic mitral continuity in two paediatric patients. CASE REPORT: Ventricular tachycardia arising from the basal region of the left ventricular summit was identified in two male patients aged 9 and 13 years. Electroanatomic mapping of ventricular arrhythmia revealed the earliest ventricular signal within the left coronary artery which was successfully ablated from the left coronary cusp. The second patient with exactly similar ECG of ventricular arrhythmia was treated by delivering energy to the aorta-mitral continuity beneath the aortic valve. No recurrences were observed during the follow-up period of 20 months. CONCLUSION: Ventricular tachycardia arising from the basal region of the left ventricular summit is very rarely observed in paediatric patients. Utilising radiofrequency catheter ablation in proximity to the source can effectively and safely eliminate tachycardia.