Transient Compression of Coronary Artery-Left Ventricular Micro-Fistulae by Stunned Myocardium in Takotsubo Syndrome

Takotsubo syndrome (TS) is an acute cardiac disease characterized by a unique regional, circumferential, and reversible left ventricular wall motion abnormality (LVWMA). The characteristic feature of LVWMA in TS is myocardial stunning, in which the affected myocardium represents a state of cardiac “cramp”. The severity of this myocardial cramp is variable. It may be severe enough to cause compression of both the intramyocardial coronary micro- and macrocirculation. Currently, only one case has been published featuring TS and compressed (or invisible) coronary artery-left ventricular micro-fistulae (CALVMF) during the acute stage of TS, along with its reappearance as the left ventricular function normalized. In this report, evidence for complete compression of CALVMF arising from both the left anterior descending artery and posterior descending artery draining into the left ventricle during the acute stage of TS in a second case is presented. This observation was confirmed by the reappearance of CALVMF on follow-up coronary angiography after left ventricular function had completely normalized. This novel finding further indicates that myocardial stunning in TS represents a state of cardiac cramp and that the coronary microvascular dysfunction observed in some patients with TS is secondary to compression of the intramyocardial resistance microcirculation.