A pathophysiologic study of tako-tsubo cardiomyopathy with F-18 fluorodeoxyglucose positron emission tomography

Abstract

Aims: Our study aims to investigate the pathophysiologic mechanism underlying tako-tsubo cardiomyopathy using F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET). Methods and results: Fifteen patients with tako-tsubo cardiomyopathy were enrolled in this study. Plasma catecholamines, cardiac troponin T (cTnT), and D-dimer were serially evaluated in all patients. Thallium-201 (201Tl) single-photon emission computed tomography (SPECT) and F-18 FDG PET were performed in 10 and eight patients, respectively. Emotional or physical stress occurred in 12 (80.0%) patients. ST-T segment abnormalities existed in all patients. Thirteen patients exhibited mildly elevated cTnT, although coronary angiography did not reveal significant stenosis in any patient. Endomyocardial biopsy specimens (n = 9) demonstrated contraction-band necrosis (n = 4) and mononuclear cell infiltration (n = 3). The levels of norepinephrine and epinephrine peaked on admission (744 ± 452 and 140 ± 166 pg/mL, respectively). There was severely reduced uptake at the apex on F-18 FDG PET image, despite slightly reduced uptake of 201Tl. Elevation of D-dimer was observed in nine patients. Conclusion: The extent of metabolic defect involving apical akinetic area was more severe than perfusion abnormality. Our data suggest that sudden emotional or physical stress may cause a catecholamine-induced metabolic disorder in the myocardium, which is probably central to this syndrome. © The Author 2007.