Lesson of the month 2: Catecholamine-induced cardiomyopathy - pitfalls in diagnosis and medical management.

Cardiomyopathy as the initial presentation of phaeochromocytoma (PCA) is uncommon. Diagnostic work-up and perioperative management may be challenging within this context. We report three cases of PCA presenting with cardiomyopathy to illustrate the pitfalls in diagnosis and management. None of the patients had typical adrenergic symptoms and all three were established on beta-blockers prior to diagnosis. Their fractionated plasma catecholamine levels were elevated and the diagnosis of PCA was confirmed with various imaging modalities and post adrenalectomy. Interpretation of fractionated catecholamine levels in the context of established cardiomyopathy is difficult as cardiac failure of any aetiology generates an adrenergic response. Hence screening all patients with idiopathic cardiomyopathy is likely to generate a high false-positive rate. However, a high index of suspicion should prompt further diagnostic work-up in patients with idiopathic cardiomyopathy for occult PCAs. Peer-reviewed guidelines are required to guide the investigation and management of suspected catecholamine-induced cardiomyopathy.