title: Contrast echocardiography reveals apparently normal coronary perfusion in a rat model of stress-induced (Takotsubo) cardiomyopathy.
abstract: OBJECTIVE
  Stress-induced cardiomyopathy (SIC) is an important differential diagnosis to acute myocardial infarction (AMI) that is associated with significant morbidity and mortality. The typical hallmark of SIC is left-ventricular apical akinesia but preserved function in basal segments. Catecholamines are postulated to play an important role in SIC but the precise pathophysiology is incompletely understood. Whether myocardial perfusion of the affected segments is impaired in SIC has been debated and remains unknown.
  
  
  RESULTS
  Myocardial contrast echocardiography (MCE) was used to study regional myocardial perfusion in a rat model of SIC. Twelve rats received 50 mg/kg isoproterenol (ISO) i.p. and were continuously monitored by MCE. Apical and basal perfusion were estimated and expressed as a ratio at baseline, 5, 10, 20, 30, 40, 50, 60, 70, 80, and 90 min post-ISO. The rats developed typical apical ballooning after 43 ± 9 min post-ISO injection. The ratio of apical:basal perfusion was close to 1.00 at all time-points and never dropped below 0.89 (95% CI never extended below 0.73). Light and electron microcoscopical investigation revealed no structural damage of myocardial vessels.
  
  
  CONCLUSIONS
  Apical perfusion is not impaired in the early phase of SIC in this rat model.
authors.affiliation: Department of Molecular and Clinical Medicine, Sahlgrenska Academy at University of Gothenburg, Bruna stråket 16, SE 413 45 Gothenburg, Sweden.
authors.forename: Bjorn
authors.initials: B
authors.lastname: Redfors
authors.forename: Yangzhen
authors.initials: Y
authors.lastname: Shao
authors.forename: Johannes
authors.initials: J
authors.lastname: Wikström
authors.forename: Alexander R
authors.initials: AR
authors.lastname: Lyon
authors.forename: Anders
authors.initials: A
authors.lastname: Oldfors
authors.forename: Li-Ming
authors.initials: LM
authors.lastname: Gan
authors.forename: Elmir
authors.initials: E
authors.lastname: Omerovic
mesh_terms: D000818:Animals; D003287:Contrast Media; D003326:Coronary Circulation / Q000502:physiology*; D004195:Disease Models, Animal; D004452:Echocardiography / Q000379:methods*; D007091:Image Processing, Computer-Assisted; D007545:Isoproterenol / Q000494:pharmacology; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D054549:Takotsubo Cardiomyopathy / Q000000981:diagnostic imaging* / Q000503:physiopathology
chemical_list: D003287:Contrast Media; D007545:Isoproterenol
keywords: Animal models of cardiovascular disease; Catecholamines; Echocardiography; Tako-tsubo syndrome