1290

Abstract

complication of PCC, ventricular tachycardia (VT) is rare and torsades de pointes (TdP) yet more rare. We report a previously healthy 12 yo boy who developed VT and TdP in the context of PCC. He presented with history of chronic headaches, acutely altered mental status, diaphoresis, blood pressure (BP) of 220/110mmHg and heart rate of 108bpm. Empiric intravenous (IV) labetalol lead to initial improvement, but 6h later, he developed multiple episodes of non-sustained VT, including one of TdP. Electrolytes were normal. QTc was prolonged to 510ms. After improvement in BP, QTc normalized, and arrhythmias did not recur. Urine normetanephrine/creatinine was 6883 (normal < 278). I-123 Metaiodobenzylguanidine (MIBG) scinitgraphy demonstrated significant uptake in the right adrenal gland with small uptake in the left adrenal gland. A right-sided adrenal PCC was confirmed by magnetic resonance imaging of the abdomen. Following prolonged alpha-blockade, the PCC was resected uneventfully; however, he remained persistently tachycardic with frequent premature ventricular contractions (PVCs), and 12h after surgery, he developed short monomorphic VT with new troponin elevation to 1.89ng/ml. His BP, QTc, and echocardiogram remained normal. VT did not recur after restarting IV labetalol, but PVCs persisted. Six weeks after surgery, his urine catecholamines normalized, and PVCs were decreasing in frequency allowing for a reduction in labetalol dose. VT and TdP in the context of PCC as experienced by our patient are very rare. Acquired long QTc and TdP (reported with hypertensive encephalopathy) and hypertensive coronary insufficiency may have contributed to their pathogenesis. Persistent ventricular arrhythmia despite BP control and tumor resection is concerning for malignant PCC. However, normal urine catecholamines make this unlikely, even with the above MIBG findings. No single factor explains the persistence of this patient's arrhythmias, which suggests that their etiology in PCC may be multifactorial and underscores the importance of close follow-up.