Mammalian hearts demonstrate the highest density of beta-adrenergic receptors in the apex although the distribution of beta-1 and beta-2 adrenoreceptors has never been mapped in the human heart.23 Increased responsiveness of the left ventricular apex to catecholamines could explain the characteristic apical ballooning of takotsubo syndrome.77 Here, ADRB2 is linked to Tako-tsubo cardiomyopathy.