The unmasking of a Brugada phenotype after pulmonary resection: A case report and implications for postoperative management

Abstract

CLINICAL SUMMARY A 78-year-old white man was diagnosed with non–small cell lung cancer by transthoracic fine-needle aspirate. His medical history included type I diabetes mellitus, hypothyroidism, emphysema, and a distant history of cholangiocarcinoma treated with surgery, chemotherapy, and radiation. He had a 30-pack-year smoking history and stopped using tobacco 20 years ago. Staging evaluation, including magnetic resonance imaging of the brain, positron emission tomography-computed tomography scan, flexible bronchoscopy, and mediastinoscopy, revealed node-negative poorly differentiated stage IA non–small cell lung cancer. The patient enrolled in a clinical trial studying the efficacy of pre-resection administration of amiodarone in reducing postoperative atrial dysrhythmias. As part of the study protocol 7 days before his operation, the patient commenced taking 200 mg of amiodarone orally twice per day. He underwent an uncomplicated left thoracotomy and left lower lobectomy, and continued to receive oral amiodarone the day after his operation. Pain control was achieved using epidural anesthesia, with the catheter positioned at the T4 level. The epidural solution consisted of 0.1% bupivacaine and 10 mg/mL of hydromorphone, infused from 4 to 6 mL/h. The patient’s postoperative course was complicated by oliguria, azotemia, hyperglycemia, and hyperkalemia. Blood urea nitrogen and serum creatinine levels increased to 39 and 1.8 mg/dL from baseline values of 22 and 0.9 mg/dL, respectively. Peak serum potassium level was measured at 6.1 mg/dL. On discovery of hyperkalemia, an electrocardiogram was obtained to assess for electrolyte-related changes. ‘‘Cove’’-type ST elevations and a right bundle branch block were noted in precordial leads V1 and V2. Known as the Brugada syndrome pattern, these findings were vastly different from the patient’s preoperative electrocardiogram (Figures 1 and 2). A medication review was undertaken. Any medications known to block cardiac sodium channels were identified and discontinued. The hyperkalemia was corrected. Serial cardiac enzymes failed to reveal an acute ischemic event. A transthoracic echocardiogram showed a mildly dilated left atrium, normal regional left ventricular wall motion, a left ventricular ejection fraction of more than 55%, and trivial mitral regurgitation. Compared with the patient’s preoperative study, the echocardiogram was unchanged. Serial electrocardiograms were obtained, and 48 hours after the Brugada pattern was noted, the electrocardiogram normalized. Throughout the period of electrocardiographic abnormality, our patient remained asymptomatic. He denied any history of syncope or near-syncope. His family history was negative for sudden cardiac death. He recovered from surgery and was discharged on the sixth postoperative day.