Arrhythmias USMLE Step 1 Practice Question
A 29-year-old man presents to the emergency department with palpitations and dyspnea. He has a 15-year history of recurrent syncope triggered by emotional stress or sudden auditory stimuli (alarm clocks, telephone rings). Physical examination reveals regular vital signs and normal cardiac auscultation. ECG demonstrates a prolonged QT interval (QTc 520 ms) with broad-based T waves. Family history is significant for sudden cardiac death in his mother at age 31 and maternal uncle at age 28, both occurring without prior cardiac symptoms. Echocardiography and cardiac MRI are normal. Which of the following is the most appropriate initial management strategy to reduce his risk of sudden cardiac death?
Answer choices
- AHigh-dose amiodarone monotherapy
- BBeta-blockers with consideration for implantable cardioverter-defibrillator (ICD) based on risk stratificationCorrect answer
- CSodium channel blocker (flecainide) to shorten the QT interval
- DCalcium channel blocker (verapamil) for AV nodal refractory period prolongation
- EPermanent pacemaker implantation to overdrive suppress ectopy
- FPotassium supplementation and strict dietary sodium restriction alone
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