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Isolation and Kv Channel Recordings in Murine Atrial and Ventricular Cardiomyocytes
11:33

Isolation and Kv Channel Recordings in Murine Atrial and Ventricular Cardiomyocytes

Published on: March 12, 2013

Unique ECG presentations and clinical management of a symptomatic LQT2 female carrying a novel de novo KCNH2 mutation

Chunlin Yin1, Ping Zhang2, Jing Yang2

  • 1Department of Cardiology, Xuanwu Hospital, Capital University of Medical Sciences, Beijing, China.

Journal of Electrocardiology
|October 18, 2017
PubMed

A 26-year-old woman, 12 days in postpartum, developed recurrent syncope and cardiac arrest. Her ECG revealed QT-prolongation associated with LQT2-specific T-U wave patterns, T wave alternans, long QT-dependent torsade de pointes (TdP) and ventricular fibrillation (VF). She also had intermittent LBBB (80bpm) on alternate beats and RBBB at sinus tachycardia (113bpm). Family genotyping revealed a novel de novo missense mutation G604C of KCNH2. Propranolol slowed heart rate and further prolonged QT interval (610ms) that caused TdP recurrence. Mexiletine combined with magnesium and potassium supplements prevented TdP/VF recurrence. This patient has remained event-free after 9-month follow-up.

Keywords:
Cardiac arrest, torsade de pointesKCNH2 mutationLong QT syndromeSudden cardiac deathSyncope

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