Our findings support previously described abnormalities of intracellular calcium handling in in endomyocardial biopsies obtained from patients with takotsubo syndrome and acute left ventricular dysfunction.20 Here, calcium-regulating proteins, such as phospholamban, sarcoendoplasmic reticulum calcium-adenosine triphosphatase (SERCA) and sarcolipin, were markedly altered suggesting that this may be responsible for the associated ventricular dysfunction. Here, PLN is linked to Tako-tsubo cardiomyopathy.