Tako-Tsubo Cardiomyopathy (TTC) and Cardiac Syndrome X (CSX) are respectively acute and chronic cardiac conditions whose clinical presentation, mimicking the onset of acute myocardial ischemia in absence of epicardial coronary disease, has progressively gained the interest of the scientific community. However, despite significant progress, their underlying pathophysiology, which seems to evoke some similarities, still remains elusive. Endothelial dysfunction and autonomic imbalance have both been individually implied in their puzzling pathogenesis.

The investigators plan to conduct our study in a cohort of TTC patients, CSX patients and healthy volunteers with the following primary objective: to assess the response of endothelial function (through the Endopat score) to the autonomic tone activation induced by a 10-minute stress mental test. The assessment of autonomic tone during activation through the evaluation of Spontaneous BaRoreflex Sensitivity (BRS) and its correlation with endothelial function (Endopat score) will represent secondary objectives.

Our study will enroll 15 patients with TTC at least six months after the event, 15 patients with classic CSX and 15 healthy volunteers who will serve as control.

Inclusion Criteria:

• Patients with the Mayo Clinic's criteria established diagnosis of TTC at least 6 month after the acute event
• Patients with CSX defined by the presence of anginal pain, positive exercise stress testing and negative coronary angiography.
• A comparable cohort of healthy volunteers age and sex-matched with patients

Exclusion Criteria:

• Short-term life-threatening pathology (life expectancy < 6 months)
• Physically unable to participate in the study
• Compliance not guaranteed
• Pregnancy
• Conditions that make BRS and Endopat measurements impossible