Pathophysiology of Takotsubo Syndrome

Excerpt

Transient left ventricular apical ballooning syndrome, takotsubo cardiomyopathy, takotsubo syndrome, broken heart syndrome, or stress-induced cardiomyopathy are interchangeable terms used to define a syndrome characterized by transient left ventricular systolic and diastolic dysfunction, electrocardiographic features, and increased levels of myocardial enzymes, similar to acute myocardial infarction, but in the absence of obstructive epicardial coronary artery disease. First described in Japan in the 1990s, the syndrome has gained worldwide attention within the scientific community over the past few decades. Takotsubo syndrome is derived from the Japanese word Takotsubo ("octopus trap" or "octopus pot"). Apical takotsubo syndrome is the most common variant, characterized by a ballooned ventricle with a narrow neck resembling the octopus trap or pot used traditionally by Japanese fishermen to catch octopuses.

The disease manifests predominantly in postmenopausal females (90% of cases) triggered by severe physical or emotional stress; natural disasters, such as earthquakes; unexpected death of relatives; or acute medical illnesses. In Japan, it is more commonly observed in men. The exact cause of takotsubo syndrome is unclear. However, evidence suggests that an adrenergic surge may contribute to myocardial toxicity or disrupt the microvasculature, leading to left ventricle dysfunction. The most common form of the syndrome is the apical variant (75-80%). Other forms include mid-ventricular (10-20%) and reverse variants (See Videos Transthoracic Echocardiogram of a Patient with Apical Takotsubo Syndrome and Transthoracic Echocardiogram of a Patient with Reverse Takotsubo Syndrome).

Patients with takotsubo syndrome classically present with acute chest pain or dyspnea, often triggered by a stressor or a psychiatric illness. The electrocardiogram (ECG) may show widespread ST-segment elevation, T-wave abnormalities, or QT prolongation. Troponin levels are moderately elevated, whereas brain natriuretic peptide (BNP) and C-reactive protein levels are markedly increased. The echocardiogram shows left ventricular dysfunction with regional wall motion abnormalities depending on the type of takotsubo syndrome. The coronary angiogram shows nonobstructive coronary arteries, and the left ventriculography shows apical ballooning (apical variant), resembling an octopus pot.