[The Doppler color detection of internal mammary artery anastomoses and a functional assessment of their patency].
BACKGROUND
Left internal mammary artery coronary graft patency is usually evaluated invasively by cardiac catheterization. The objective of this study was to assess the ability of a high-frequency transthoracic Doppler echocardiographic system in the evaluation of patency and flow velocities changes in left internal mammary artery.


METHODS
Twenty-two patients (63 +/- 9 years, 17 male) who had previously undergone left internal mammary artery to left anterior descending artery were evaluated by transthoracic echocardiography, with an Acuson Sequoia C256 equipment (Acuson, Mountain view, USA), placing the transducer (5 MHz) in the second-third left intercostal space. Left internal mammary artery flow was considered to be found in the presence of one systolic/diastolic biphasic blood flow. Dipiridamol 0.5 mg/kg was administered in absence of contraindications in order to evaluate the flow reserve.


RESULTS
In 16 patients (73%), a biphasic systolic-diastolic flow was visualized. Peak velocity of systolic and diastolic waves was 38 +/- 13 and 37 +/- 15 cm/s, respectively. Eleven patients received i.v. dipiridamol 0.5 mg/kg. After dipiridamol, systolic and diastolic velocities rose from 32 +/- 8 to 43 +/- 14 cm/s (p = 0.0429) and from 25 +/- 8 to 50 +/- 17 cm/s (p = 0.0002), respectively (an increasing of 33 +/- 22% and 103 +/- 46% over the baseline, respectively).


CONCLUSIONS
This descriptive study shows that a non-invasive functional evaluation of left internal mammary artery grafts by a transthoracic approach with a high-frequency echocardiographic equipment is possible.
Moreno
R
R
Departamento de Cardiología, Hospital General Universitario Gregorio Marañon, Madrid.
García-Fernández
M A
MA
Moreno
M
M
Bermejo
J
J
Silva
J
J
Vallejo
J L
JL
Delcán
J L
JL
D000368:Aged; D006328:Cardiac Catheterization; D017023:Coronary Angiography; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D004176:Dipyridamole; D018618:Echocardiography, Doppler, Color / Q000295:instrumentation / Q000706:statistics & numerical data; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging*; D006801:Humans; D007387:Internal Mammary-Coronary Artery Anastomosis; D008297:Male; D008323:Mammary Arteries / Q000000981:diagnostic imaging*; D008875:Middle Aged; D014665:Vasodilator Agents
D014665:Vasodilator Agents; D004176:Dipyridamole