Noninvasive quantitative evaluation of the patency of internal mammary artery grafts to the left anterior descending coronary artery by transthoracic Doppler echocardiography.
OBJECTIVE
Evaluation of left anterior descending coronary artery (LAD) flow by transthoracic Doppler echocardiography (TTDE) may allow assessment of anastomosis of the internal mammary artery (IMA) grafted to the LAD. This study tested the feasibility of TTDE to evaluate anastomotic stenosis of the IMA grafted to the LAD.


METHODS
TTDE was performed in 66 patients (48 men and 18 women, mean age 67 +/- 10 years) with left or right IMA grafts to the LAD. The distal IMA flow at the anastomosis was visualized and the percentage stenosis was evaluated by the continuity equation using the anastomotic and pre-anastomotic flow velocity measured by TTDE as well as by angiography. If the anastomotic flow was not visualized by TTDE, the absence of augmented diastolic flow of the proximal IMA, by using the supraclavicular approach, with diastolic to systolic mean velocity ratio < 0.25 was considered as anastomotic occlusion.


RESULTS
Anastomotic flow was visualized and the percentage stenosis was obtained by the continuity equation in 50 patients. In 4 of the remaining 16 patients, the proximal IMA flow by TTDE showed the occlusion pattern. In these 54 (82%) patients, the percentage stenosis by TTDE showed a significant correlation with that by angiography (r2 = 0.86, p < 0.0001). In all the remaining 12 patients with the patent proximal IMA pattern but without visualized anastomotic flow, the patency was confirmed by angiography.


CONCLUSIONS
TTDE enables direct visualization and quantitative evaluation of the anastomotic patency in patients with IMA graft to the LAD.
Mizukami
Naoko
N
Department of Clinical Laboratory, Kagoshima University Hospital, Sakuragaoka 8-35-1, Kagoshima, Kagoshima 890-8520. mizukami@m.kufm.kagoshima-u.ac.jp
Minagoe
Shinichi
S
Otsuji
Yutaka
Y
Neishi
Yoji
Y
Akasaka
Takashi
T
Hamasaki
Shuichi
S
Yuasa
Toshinori
T
Miyata
Masaaki
M
Maruyama
Seiro
S
Yoshida
Kiyoshi
K
Sakata
Ryuzo
R
Tei
Chuwa
C
D000368:Aged; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery; D004452:Echocardiography; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D007387:Internal Mammary-Coronary Artery Anastomosis; D008297:Male; D008323:Mammary Arteries / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D008875:Middle Aged; D014654:Vascular Patency