The Coronary Artery Changes and Complications Caused by Takotsubo Syndrome: A Review With Novel Observations.

Takotsubo syndrome (TS) is an acute cardiac disease entity with a clinical presentation identical to that of an acute coronary syndrome (ACS). The terms tsubo- or takotsubo-shaped were introduced at the beginning of the 1990s to describe the silhouette of the left ventricle during systole in patients with a clinical picture similar to myocardial infarction (MI) but with no obstructive coronary arteries. Notably, TS is not a MI and is caused by a different pathogenic mechanism. Innumerable emotional and physical stress factors have been reported to trigger TS, with ACS identified as one of the known physical trigger factors for TS. The myocardial stunning, which is the characteristic feature of left ventricular wall motion abnormality (LVWMA) in TS, was first reported in patients with ACS and also used to describe LVWMA when the term takotsubo-shaped was introduced in 1990. Cases, series of cases, and studies on that ACS may trigger TS have been reported. TS is also known to cause numerous cardiac complications, such as heart failure, pulmonary edema, cardiogenic shock, life-threatening arrhythmias, left ventricular outlet tract obstruction, and cardiac thromboembolic complications. In addition to MI caused by coronary thromboembolic complications, TS may also cause other changes or complications in the coronary artery system, including the intramyocardial resistance microcirculation, the intramyocardial conductance vessels as the septal branches from both the left anterior descending artery and the posterior descending artery, the coronary segments with myocardial bridging, the epicardial coronary arteries, and coronary artery-left ventricular micro-fistulae (CALVMF). This paper reviews these coronary artery complications or changes caused by TS. Notably, the transient compression of CALVMF during the acute stage of TS and reappearance during normalization of the left ventricular function represent novel observations.