Possible Deslanoside-Induced Left Posterior Fascicular Ventricular Tachycardia: A Case Report.

A 73-year-old man with paroxysmal atrial fibrillation and no structural heart disease developed left posterior fascicular ventricular tachycardia (LPFVT) shortly after intravenous Deslanoside administration.

• The patient had paroxysmal AF and no structural heart disease.
• LPFVT onset had a close temporal relationship with Deslanoside drug administration.
• The arrhythmia occurred following intravenous administration of Deslanoside.
• This represents a case report of a single patient (n=1).

A shorter latency to arrhythmia onset was observed following a second intravenous dose of Deslanoside compared to the first dose.

• The patient received at least two intravenous doses of Deslanoside.
• The latency between drug administration and LPFVT onset was shorter after the second dose than after the first dose.
• This dose-response temporal relationship was noted as supporting a possible causal association between Deslanoside and LPFVT.

Cardiac glycosides, while effective for ventricular rate control in atrial fibrillation, may occasionally precipitate Purkinje-related ventricular tachycardia.

• Deslanoside is a cardiac glycoside widely used for ventricular rate control in atrial fibrillation.
• The authors suggest Deslanoside may have facilitated LPFVT, a form of Purkinje-related ventricular tachycardia.
• The case highlights a potential proarrhythmic effect of cardiac glycosides involving the Purkinje system.
• This finding is based on a single case report and the authors use cautious language ('possible' and 'may have facilitated').