Is there an association between Fahr's disease and cardiac conduction system disease?: A case report
A 19-year-old Arab female patient was referred to Royal Hospital, Muscat, Oman in July 2011 from a regional hospital for pacemaker insertion. Her past medical history included cognitive impairment and asymptomatic congenital complete heart block (CHB) since birth. She had referred to the regional hospital with one month history of recurrent fainting attacks lasting for a few minutes, sometimes associated with generalized tonic-clonic seizures. She was diagnosed with epilepsy. Her treatment started with sodium valproate. There was no history of fever, rash, head trauma or any drug abuse. Her brain CT scan had shown bilateral basal ganglia calcification which was not present previously. Her family history was negative for any cardiac or neurological disorders. She was born of consanguineous parents and had three siblings who were normal. Her echocardiogram was normal and her baseline ECG showed incomplete right bundle branch block with left anterior fascicular block, normal PR/QT interval () with intermittent narrow QRS CHB and a ventricular rate of 40 beats per minute (bpm) ().\nShe was admitted during one of the fainting episodes. During the hospitalization period, she developed recurrent Stokes-Adams attacks with seizures and the monitor demonstrated intermittent advanced varying atrioventricular (AV) blocks with wide QRS escape rhythm suggesting infrahisian block (). The atrial rate during these advanced AV blocks was 250-300 bpm indicating either atrial tachycardia or atrial flutter. This was followed by asystolic cardiac arrest with monitor indicating prolonged P-wave asystole (). Immediate cardiopulmonary resuscitation was initiated and she was treated with intravenous adrenaline (total dose = 3 mg), atropine (total dose = 3 mg) followed by dopamine infusion (10 mcg/kg/min). She had been successfully resuscitated along with a brief ventilator support and transferred to our center on dopamine infusion, with a stable heart rate of 100 bpm. On examination at our hospital, she demonstrated cognitive impairment, mild rigidity, limb ataxia, and tremors with normal eye. She also underwent fundus, cranial nerve, and other neurological examinations. Her cardiac examination and transthoracic echocardiogram were normal. Brain CT scan in our hospital confirmed bilateral “cloudy” looking symmetric basal ganglia calcification (). Secondary causes of the calcifications were excluded by laboratory testing. Serum concentration of calcium, phosphorus, magnesium, alkaline phosphatase, calcitonin, parathyroid hormone, sodium valproate level and autoantibodies were normal. The electroencephalography (EEG) showed generalized theta slowing suggesting developmental delay without any epileptic focus. The neurological manifestations along with basal ganglia calcification suggested FD. Genetic testing was refused by the family. She underwent single chamber permanent pacemaker (VVI) implantation with ventricular rate set at 70 bpm. She did not experience any recurrence of arrhythmias or fainting attacks/seizures. At six-month follow-up, she was 80% pacemaker dependent with no recurrence of seizures.