title: Noninvasive functional assessment of left internal mammary artery grafts by transcutaneous Doppler echocardiography.
abstract: A noninvasive method to assess left internal mammary artery (LIMA) patency and function would be useful because this vessel is frequently used for revascularization of the left anterior descending coronary artery. The purpose of this study was to assess the feasibility of measuring changes in LIMA velocities by transcutaneous Doppler during dipyridamole-induced vasodilation. Twenty-five patients with a LIMA graft anastomosed to the left anterior descending coronary artery were studied at least 1 month after surgery by the use of a 5 MHz transducer placed in the left supraclavicular fossa. Doppler velocity parameters were measured at baseline and after intravenous administration of dipyridamole. Dipyridamole increased mean velocity by 127% +/- 54% (p < 0.001), systolodiastolic velocity time integral by 89% +/- 31% (p < 0.001), and diastolic-to-systolic peak velocity ratio from 0.7 +/- 0.3 to 1.2 +/- 0.4 (p < 0.001). The dipyridamole-to-baseline mean velocity ratio was 2.3 +/- 0.5. We conclude that it is possible to measure dipyridamole-induced changes in LIMA flow velocities and thus obtain an index of LIMA blood velocity reserve by transcutaneous Doppler echocardiography.
authors.affiliation: Department of Cardiology, Mont-Godinne Hospital, University of Louvain, Yvoir, Belgium.
authors.forename: E
authors.initials: E
authors.lastname: Rombaut
authors.forename: P
authors.initials: P
authors.lastname: Vantrimpont
authors.forename: O
authors.initials: O
authors.lastname: Gurné
authors.forename: P
authors.initials: P
authors.lastname: Chenu
authors.forename: E
authors.initials: E
authors.lastname: Schroeder
authors.forename: M
authors.initials: M
authors.lastname: Buche
authors.forename: Y
authors.initials: Y
authors.lastname: Louagie
authors.forename: P
authors.initials: P
authors.lastname: Eucher
authors.forename: B
authors.initials: B
authors.lastname: Marchandise
mesh_terms: D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity / Q000187:drug effects / Q000502:physiology; D003326:Coronary Circulation / Q000502:physiology; D004176:Dipyridamole; D015150:Echocardiography, Doppler / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D007387:Internal Mammary-Coronary Artery Anastomosis; D008297:Male; D008875:Middle Aged; D014654:Vascular Patency / Q000502:physiology; D014665:Vasodilator Agents
chemical_list: D014665:Vasodilator Agents; D004176:Dipyridamole