October 13, 2008Journal of Cardiovascular Electrophysiology289 citations
View Full PaperVentricular Fibrillation with Prominent Early Repolarization Associated with a Rare Variant of KCNJ8/KATP Channel
Structured PICO
Does quinidine prevent recurrent ventricular fibrillation in a patient with early repolarization syndrome associated with a KCNJ8 variant?
P
Population
14-year-old female resuscitated from sudden death due to ventricular fibrillation with prominent early repolarization pattern and >100 recurrences
I
Intervention
Isoproterenol infusion (acute) and quinidine (long-term)
O
Outcome
Suppression of ventricular fibrillation recurrences and restoration of normal ECGhard clinical
Quinidine successfully suppressed recurrent ventricular fibrillation in a patient with early repolarization syndrome linked to a rare KCNJ8 variant.
Abstract
This young female (14 years) was resuscitated in 2001 following an episode of sudden death due to VF. All examinations including coronary angiogram with ergonovine injection, MRI, and flecainide or isoproterenol infusion were normal. The patient had multiple (>100) recurrences of VF unresponsive to beta-blockers, lidocaine/mexiletine, verapamil, and amiodarone. Recurrences of VF were associated with massive accentuation of the early repolarization pattern at times mimicking acute myocardial ischemia. Coronary angiography during an episode with 1. 2 mV J/ST elevation was normal. Isoproterenol infusion acutely suppressed electrical storms, while quinidine eliminated all recurrences of VF and restored a normal ECG over a follow-up of 65 months. Genomic DNA sequencing of K (ATP) channel genes showed missense variant in exon 3 (NC₀00012) of the KCNJ8 gene, a subunit of the K (ATP) channel, conferring predisposition to dramatic repolarization changes and ventricular vulnerability.