title: Assessment of coronary microcirculation in patients with takotsubo-like left ventricular dysfunction.
abstract: BACKGROUND
  The precise mechanism of takotsubo-like left ventricular (LV) dysfunction remains unclear.
  
  
  RESULTS
  Eight consecutive patients with takotsubo-like LV dysfunction were studied. In the acute phase and 3 weeks later, the coronary flow velocity spectrum and coronary flow velocity reserve (CFVR) were recorded by Doppler guidewire. The deceleration time of diastolic velocity (DDT; ms) was measured from the peak diastolic velocity to the point where the extrapolated line intersected the baseline. In all cases, CFVR of the 3 coronary arteries increased during follow-up (1.7+/-0.5 to 2.4+/-0.5 for the left anterior descending artery (p < 0.05), 1.7+/-0.5 to 2.7+/-0.8 for the left circumflex artery (p < 0.05) and 1.7+/-0.3 to 2.5+/-0.4 for the right coronary artery (p < 0.05)). In addition, the DDT of all coronary arteries increased during follow-up.
  
  
  CONCLUSIONS
  Decreased CFVR and short DDT were demonstrated in patients with takotsubo-like transient LV dysfunction in the acute phase, and these findings improved 3 weeks later, which suggests that coronary microvascular dysfunction may be a causative mechanism.
authors.affiliation: Department of Cardiology, Kawasaki Medical School, Kurashiki, Japan. tteru@med.kawasaki-m.ac.jp
authors.forename: Teruyoshi
authors.initials: T
authors.lastname: Kume
authors.forename: Takashi
authors.initials: T
authors.lastname: Akasaka
authors.forename: Takahiro
authors.initials: T
authors.lastname: Kawamoto
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Yoshitani
authors.forename: Nozomi
authors.initials: N
authors.lastname: Watanabe
authors.forename: Yoji
authors.initials: Y
authors.lastname: Neishi
authors.forename: Nozomi
authors.initials: N
authors.lastname: Wada
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Yoshida
mesh_terms: D000368:Aged; D001783:Blood Flow Velocity; D016022:Case-Control Studies; D003326:Coronary Circulation; D015150:Echocardiography, Doppler; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000503:physiopathology; D008875:Middle Aged; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology*