Mechanisms of Takotsubo cardiomyopathy; role of microcirculatory dysfunction

Takotsubo cardiomyopathy is characterized by reversible left ventricular dysfunction typically preceded by an emotional or a physical stressor. The underlying pathophysiologic mechanisms include multivessel coronary vascular spasm, microvascular dysfunction, neurogenic stunning of the myocardium and catecholamine surge. Microcirculatory dysfunction may play a key role in the evolution of this syndrome especially in the acute phases of the illness. Severe invasive and noninvasive modalities are utilized to ascertain any compromise in coronary perfusion in Takotsubo cardiomyopathy, including Doppler guidewire technique, Thrombolysis in myocardial infarction (TIMI) frame count (TFC), TIMI myocardial perfusion grade (TMPG) and nuclear imaging techniques. TIMI frame count can be utilized as a diagnostic marker and clinical indicator in assessment of microvascular function or coronary flow in patients with Takotsubo cardiomyopathy.