Percutaneous renal sympathetic denervation combined with empirical Purkinje de-networking for electrical storm in congenital long QT syndrome after cardiac sympathetic denervation: a case report with two consecutive patients

Electrical storm in congenital long QT syndrome (LQTS) may persist despite maximal β‑blockade, implantable cardioverter-defibrillator (ICD) therapy, and surgical cardiac sympathetic denervation (SCSD). When no reproducible premature ventricular contractions are documented, catheter ablation targets and procedural endpoints are uncertain. We report two consecutive young adults (LQTS1 and LQTS2) with recurrent ventricular fibrillation and appropriate ICD shocks despite prior left SCSD. In both, sinus-rhythm left ventricular substrate mapping showed no scar or abnormal electrograms. A mechanistic strategy was therefore selected: empirical mapping and elimination of Purkinje potentials along the distal left anterior and posterior fascicles (“Purkinje de-networking”), followed by percutaneous renal sympathetic denervation in the same session. Programmed stimulation with and without isoproterenol was non-inducible after ablation, and both patients remained free of ventricular arrhythmia recurrence and ICD therapies during follow-up (16 and 8 months) on β‑blocker therapy. This combined, percutaneous bailout approach may be considered in highly selected LQTS patients with electrical storm refractory to standard therapies.