title: Noninvasive quantitative evaluation of the patency of internal mammary artery grafts to the left anterior descending coronary artery by transthoracic Doppler echocardiography.
abstract: 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.
authors.affiliation: Department of Clinical Laboratory, Kagoshima University Hospital, Sakuragaoka 8-35-1, Kagoshima, Kagoshima 890-8520. mizukami@m.kufm.kagoshima-u.ac.jp
authors.forename: Naoko
authors.initials: N
authors.lastname: Mizukami
authors.forename: Shinichi
authors.initials: S
authors.lastname: Minagoe
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Otsuji
authors.forename: Yoji
authors.initials: Y
authors.lastname: Neishi
authors.forename: Takashi
authors.initials: T
authors.lastname: Akasaka
authors.forename: Shuichi
authors.initials: S
authors.lastname: Hamasaki
authors.forename: Toshinori
authors.initials: T
authors.lastname: Yuasa
authors.forename: Masaaki
authors.initials: M
authors.lastname: Miyata
authors.forename: Seiro
authors.initials: S
authors.lastname: Maruyama
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Yoshida
authors.forename: Ryuzo
authors.initials: R
authors.lastname: Sakata
authors.forename: Chuwa
authors.initials: C
authors.lastname: Tei
mesh_terms: 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