Pharmacological treatment of short-coupled idiopathic ventricular fibrillation: A review

Figures

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  Fig. 1. Two delayed afterdepolarizations (A), the latter initiating a premature ventricular contraction during ventricular repolarization causing polymorphic ventricular tachycardia.

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  Fig. 2. Implantable cardioverter-defibrillator electrogram showing polymorphic ventricular tachycardia initiated by a short-coupled premature ventricular contraction degenerating into ventricular fibrillation before a successful shock was applied in a 47-year old man treated with bisoprolol 2.5 mg daily who initially presented with out-of-hospital cardiac arrest one year earlier. Following this recurrence, bisoprolol was replaced with quinidine 600 mg daily, and he remained asymptomatic until last follow-up (3.5 years).

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  Fig. 3A. 12-lead ECG showing two salvo's of nonsustained polymorphic ventricular tachycardia in a patient with short-coupled idiopathic ventricular fibrillation during electrical storm despite treatment with quinidine 800 mg daily and an adequate quinidine trough level of 3.4 mg/L.

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  Fig. 3B. Resolution of electrical storm after quinidine was replaced with cilostazol 300 mg daily.

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  Fig. 4. Proposed chronic pharmacological treatment algorithm for patients with SCIVF. SCIVF, short-coupled idiopathic ventricular fibrillation. ∗Radiofrequency ablation of the initiating malignant PVC may be considered depending on local resources and expertise and patient characteristics (e.g. the presence or absence of frequent isolated premature ventricular contractions similar to those initiating the ventricular arrhythmias to allow for activation mapping).§Recommended starting dose of cilostazol is 100 mg twice daily. Recommended dose of bepridil is 200–400 mg once daily.