"A BROKEN TRANSPLANTED HEART": A CASE OF TAKOTSUBO SYNDROME IN A HEART TRANSPLANT RECIPIENT

Abstract 75–year–old female patient went to the emergency department for oppressive chest pain radiating to the left arm and dyspnea, developed after an argument with family members. The patient underwent heart transplant in 2010 because of chronic ischemic heart disease. In history: systemic arterial hypertension, former smoking, dyslipidemia, and chronic renal failure. At blood tests: TnIHS 78.4 ng/L (<29 ng/L), CK–MB 1.9 microg/L, PROBNP–NT 43,000 pg/ml, creatinine 2 mg/dL. ECG showed inverted T waves in DI, AVL and V4 to V6 (fig 1). Transthoracic echocardiography was remarkable for a moderate reduction in systolic function (EF 38%), akinesia of apical portion, mid–segment of the IVS and mid–segment of posterior wall. Coronarography showed epicardial coronaries free of angiographically significant lesions. We decided to not perform ventriculography to avoid worsening renal function. At clinical stabilization, the patient underwent cardiac MRI with evidence of hypokinesia of the mid–ventricular segments with preserved global systolic function and hypo/akinesia of right ventricular apex with endocavitary thrombosis. Tissue characterization images were compatible with the presence of diffuse phlogistic involvement of the left ventricular myocardium (most evident at the mid–ventricular segments), in the absence of areas of myocardial necrosis. On pre–dimission echocardiogram, global left ventricular systolic function appeared markedly improved (auto EF 52%). DISCUSSION Our case is a rare case of Takotsubo syndrome (TS) in a transplanted heart. While TS accounts for 1–2% of all ACS in the general population, there is no precise data on its prevalence in heart transplant recipients. Although the pathophysiological mechanism underlying TS is still debated, there is evidence of hyperactivation of the sympathetic system with excessive catecholamine release. What is particular in our clinical case is that transplanted heart is denervated (because of resection of the post–ganglionic neural axons), although in some patients there is progressive reinnervation starting around the second year. Myocardial scintigraphy with iodine–123 meta iodobenzylguanidine can be used to study reinnervation. In our case, the presence of typical angor may be a clinical indicator of reinnervation, as many transplant patients present with CAV in the absence of chest pain.