Abstract
Background: Takotsubosyndrome (TTS) isanacute cardiomyopathyassociatedwithintense physical oremotion- al stress. The precise mechanisms of the disease remain unclear. The aimof this studywas to study alterations in endothelial function, vascular compliance and structure and muscle sympathetic activity in the stable phase of the disease. Methods: In this prospective observational study, patients with TTS and controlsmatched for age, sex, cardiovas- cular risk factors andmedicationswere recruited. Flow-mediated vasodilatation (FMD) as ameasure of endothe- lial dysfunction was the primary endpoint. Secondary endpoints included measurements of arterial stiffness, carotid atherosclerosis, quality of life and laboratory parameters. In a subset of patients, muscle sympathetic ac- tivity was measured before and after stress tests. Results: The study included 22 TTS patients and 21 matched controls. A significant increase in endothelial dys- functionwas seen in TTS compared to controls (FMD 3.4±2.4% vs. 4.8±1.9%, p=0.016). No significant differ- ences in arterial stiffness, intima-media thickness, quality of life and laboratory markers including endothelin-1 were noted. TTS patients showed a reduced carotid total plaque area compared to controls (TPA 17.3±15.1 vs 24.7±12.8mm2, p=0.02).Atrendof increasedmuscle sympathetic activity at restwas observed inTTS patients vs. controls (53.5±28.4 vs. 29.4±16.5 bursts/100 heart beats, p=0.09)with no significant differences inmus- cle sympathetic activity in response to stress. Conclusions: Our findings underscore the importance of endothelial dysfunction in patients with TTSwhich may be involved in the pathophysiology of this syndrome. ClinicalTrials.gov