Long QT syndrome and pregnancy – case report

Introduction: Congenital long QT syndrome (LQT) is defined by a prolongation of the ventricular repolarization due to inherited mutations of genes encoding for sodium and/or potassium ion channels, predisposing the patient to syncope, ventricular arrhythmias, especially torsade des pointes, and sudden death. The diagnosis is based on clinical and electrocardiographic findings (prolonged QT interval), also being available genetic testing. Mutations in several ion-channel genes are known to cause LQTS, the most common of which are found in potassium-channel KCNQ1 (LQT1) and hERG (LQT2) genes, and in the sodium-channel SCN5A (LQT3) gene. Methods: We report the case of a 27 year old pregnant patient who presented at the emergency room at 8 weeks of gestation with repeated episodes of syncope and irregular palpitations for the last 12 hours. The electrocardiogram is extremely varied with multiple wide-QRS tachycardias, with torsade des pointes episodes and a measured QT interval of 800 milliseconds. Because of the extreme QT prolongation being the expression of prolonged ventricular repolarization, the patient has 2:1 AV block. The patient has no dyselectrolytemia and the echocardiogram shows a structurally normal heart. The patient’s history reveals she is on phenobarbital since the age of 13 for presumed epileptic seizures, but with a normal electroencephalogram. Results: Problems arise regarding the acute treatment for this patient, as well as sudden death prophylaxis by internal cardiac defibrillator implant needing intra procedural radioscopic control, the patient being pregnant. It was performed temporary pacing at 100 bpm with clinical improvement, and the patient underwent an implantation of a dual chamber ICD. Conclusions: Early diagnosis and onset of specific treatment for this fatal syndrome is essential. The diagnosis is based on clinical features and electrocardiographic lengthening of the QT interval. Nowadays, genetic testing is also available in order to identify the exact mutation. The particularity of this case is represented both by the extremely various electrical aspect of this patient, and the worsening of the symptoms at week 8 of pregnancy, knowing that in long QT syndrome, especially type 2, the exacerbation of symptoms happens in the last stage of pregnancy and postpartum.

ISSN – online: 2734 – 6382
ISSN-L 1220-658X
ISSN – print: 1220-658X
The Romanian Journal of Cardiology is indexed by:
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CODE: 379
CME Credits: 10 (Romanian College of Physicians)