
Rare case of digenic inheritance of long QT syndrome type 2 and type 6
This article describes the case of a 37-year-old Iraqi woman living in the Netherlands diagnosed with digenic inheritance of long QT syndrome type 2 and type 6. The woman presented to the emergency department with an out-of-hospital cardiac arrest (OHCA) due to ventricular fibrillation (VF). She had no cardiac history and had suddenly collapsed that evening. Before the event, she would only experience dizziness at times. The police started basic life support after 2 to 3 minutes. Whereas the paramedics arrived 10 minutes later.
Paramedics documented VF. The patient’s sinus rhythm restored after three direct shocks. الكازينو Her medical history revealed that she did not smoke or use drugs. She was currently on medications including diclofenac, mebeverine and vitamin supplements. لعبة تربح فلوس In addition, she underwent a gastric banding operation a year ago with an unremarkable recovery. لعبة كازينو Information about her family history was limited because her mother and four siblings lived in different countries around the world. However, her father passed away because of complications of diabetes mellitus at the age of 55. Similarly, she had no family history of cardiac disorders.
She had two autistic sons but both were in good physical health.
Examination and diagnosis
Electrocardiogram was remarkable of sinus rhythm with a frequency of 103 beats per minute and frequent premature ventricular complexes in bigeminy pattern with a QTc interval of 419 ms. Although, there were no evident abnormalities on computed tomography scan of the thorax and cerebrum. After 24 hours of therapeutic hypothermia, she regained consciousness with significant neurologic recovery. Left and right ventricular functions were normal with no valvular abnormalities.
Initial treatment included propranolol because of episodes of frequent premature heart beats, non-sustained ventricular tachycardia and prolonged QTC intervals. In addition, heart rhythm was abnormal. Doctors prescribed cardarone which led to ventricular fibrillation requiring cardioversion. Cordarone was discontinued. Laboratory tests showed hyponatremia, hypokalemia and normal calcium level. Ventricular tachyarrhytmias persisted even after electrolyte corrections. QTC levels were between normal and severely prolonged during hospitalisation. Doctors advised discontinuing treatment with propranolol because of tachycardia. Flecainide helped restore sinus rhythm. There were no signs of coronary artery stenosis on coronary angiography. MRI findings were also insignificant.
A dual-chamber implantable cardioverter-defibrillator was implanted as secondary prevention.
References
A Rare Case of the Digenic Inheritance of Long QT Syndrome Type 2 and Type 6 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6610752/