Assessment of coronary microcirculation in patients with takotsubo-like left ventricular dysfunction.
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.
Kume
Teruyoshi
T
Department of Cardiology, Kawasaki Medical School, Kurashiki, Japan. tteru@med.kawasaki-m.ac.jp
Akasaka
Takashi
T
Kawamoto
Takahiro
T
Yoshitani
Hidetoshi
H
Watanabe
Nozomi
N
Neishi
Yoji
Y
Wada
Nozomi
N
Yoshida
Kiyoshi
K
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*