Takotsubo cardiomyopathy following unintentionally large subcutaneous adrenaline injection: a case report

INTRODUCTION: Stress cardiomyopathy, also known as takotsubo syndrome, is characterized by transient left ventricular dysfunction not attributable to obstructive epicardial coronary artery disease. Several pathological mechanisms have been proposed, including multivessel coronary artery vasospasm, coronary microcirculatory dysfunction, and excess catecholamine secretion. CASE PRESENTATION: A 68-year-old male presented to our institution for elective surgical removal of a cutaneous basal cell carcinoma on the right side of his face. Within minutes following the administration of local anaesthesia, the patient developed severe hypertension, tachycardia, ST-segment elevation on the electrocardiogram, and non-sustained broad-complex tachycardia. Urgent cardiac catheterization revealed non-obstructive coronary artery disease and left ventriculography demonstrated apical hypokinesia and moderate systolic dysfunction consistent with the takotsubo syndrome. On review of the medications administered, it was noted that an unintentionally large dose of adrenaline (4mg) had been injected subcutaneously with lignocaine. He was monitored in the coronary care and recovered fully with supportive care only. Bisoprolol was initiated on day 1 post procedure. On follow-up one month later, his left ventricular function had normalized. DISCUSSION: Our case report provides direct evidence supporting the pathogenetic role of excess catecholamine secretion in the development of the takotsubo syndrome. A review of the literature reveals that both exogenous catecholamine administration (adrenaline injection in the context of anaphylaxis or infiltrative anaesthesia) and excess endogenous catecholamine (phaechromocytoma) secretion has been associated with the takotsubo syndrome. Local infiltrative anaesthesia with the addition of adrenaline is commonly used as a vasoconstrictor in a wide variety of surgical procedures. To reduce the risk of adverse events, the lowest effective concentration of adrenaline to provide pain control and vasoconstriction is recommended.