Electrical Storm in Long QT Syndrome: A Percutaneous Dual Approach

01About the report

Congenital long QT syndrome is an inherited cardiac channelopathy. In a structurally normal heart it can lead to polymorphic ventricular tachycardia, ventricular fibrillation and sudden cardiac death. Beta-blockers are first-line therapy. A subset of patients still has recurrent arrhythmias with appropriate implantable cardioverter-defibrillator (ICD) shocks. Left surgical cardiac sympathetic denervation can reduce that burden. Electrical storm may still persist in rare, highly refractory cases.

This case report, co-authored by Prof. Dr. Hakan Uçar, describes two consecutive young adults whose electrical storm continued despite beta-blockade, an ICD and prior left surgical cardiac sympathetic denervation.

02What did the authors describe?

When no reproducible premature ventricular contraction is documented, a catheter ablation target and a procedural endpoint are uncertain. The authors describe the strategy they selected: mapping and elimination of Purkinje potentials along the distal left anterior and posterior fascicles (“Purkinje de-networking”), followed in the same session by percutaneous renal sympathetic denervation.

This is not a treatment guideline. It is an observation in two consecutive patients, which the authors describe as a bailout approach that may be considered in highly selected patients whose electrical storm is refractory to standard therapy.

03The two patients

In both, left ventricular mapping showed no scar and no abnormal electrograms. A consistent triggering premature beat was not demonstrated. After the procedure, programmed stimulation with and without isoproterenol did not induce ventricular arrhythmia. Both patients continued a beta-blocker.

These are two consecutive cases. They should not be read as a success rate for a method.

04How the authors interpret the outcome

The authors write that the separate contributions of the two procedures cannot be isolated in this series. Because epicardial mapping was not performed, an unrecognized epicardial substrate cannot be excluded. Non-inducibility at the end of the procedure is presented as an immediate observation. The clinically meaningful outcomes they name are long-term freedom from arrhythmia and the absence of ICD therapies.

05Study limitations

The limits the article itself places in the foreground are these.

• The number of patients is two.
• The contributions of Purkinje de-networking and renal denervation cannot be separated.
• Epicardial mapping was not performed.
• Non-inducibility is not presented as a definitive endpoint.

CRediT AUTHOR CONTRIBUTION

06Prof. Dr. Hakan Uçar’s contribution

According to the publisher’s author contribution statement, Prof. Dr. Hakan Uçar is listed for conceptualization, procedural execution and data acquisition, and review and editing of the manuscript. Electrophysiological mapping and ablation are attributed to Tolga Aksu and Emrah Ermiş, and supervision to Tolga Aksu.

• Conceptualization
• Procedural execution and data acquisition
• Writing – review & editing

The listed affiliation is the Department of Cardiology at Istanbul Aydin University Medical Park Florya Hospital.

07Original publication