QT prolongation and monomorphic VT caused by pheochromocytoma.
BACKGROUND
Pheochromocytoma may present with ECG abnormalities as one of the few clues to the diagnosis.


RESULTS
A 30-year-old woman presented with chest pain and a QTc of 525 ms. Four weeks later following a syncopal episode, her QTc was 660 ms. Short runs of monomorphic ventricular tachycardia were recorded. Investigations revealed an adrenal pheochromocytoma. Her QTc normalized after excision of the tumor. Comprehensive QT gene screening of KCNQ1, KCNH2, SCN5A, KCNE1, and KCNE2 was negative.


CONCLUSIONS
Pheochromocytoma may induce monomorphic VT and QT prolongation. The interaction of different catecholamines may have a compounding effect on cardiac repolarization.
Paulin
Frédéric L
FL
Arrhythmia Service, Division of Cardiology, University of Western Ontario, Canada.
Klein
George J
GJ
Gula
Lorne J
LJ
Skanes
Allan C
AC
Yee
Raymond
R
Krahn
Andrew D
AD
D000310:Adrenal Gland Neoplasms / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D000328:Adult; D004562:Electrocardiography / Q000379:methods; D005260:Female; D006801:Humans; D008133:Long QT Syndrome / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D010673:Pheochromocytoma / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology