Dynamic assessment of a composite arterial Y-graft achieving complete myocardial revascularization: transthoracic echo-Doppler correlates with myocardial scintigraphy.
BACKGROUND
Composite arterial grafts are presently being used ever more frequently in coronary bypass surgery. We assessed the composite radial artery and in situ left internal thoracic artery Y-graft by means of transthoracic echo-Doppler and myocardial perfusion scintigraphy (MPS).


METHODS
In 53 patients who underwent complete myocardial revascularization using only this composite arterial graft, good transthoracic echographic images and pulsed Doppler signals of the Y-graft main stem were obtained at rest and early after standard exercise; the echographic parameters were measured. Stress/rest MPS was the gold standard for residual myocardial ischemia. The patients with negative MPS were divided into groups according to the number of coronary vessels grafted and their history of preoperative myocardial infarction.


RESULTS
The diastolic-to-systolic ratio of the peak velocities and velocity-time integrals both at rest and after stress, and the stress-to-rest ratio of the diastolic peak velocities and diastolic velocity-time integrals in the negative MPS patients were significantly greater than in the 6 positive MPS patients. However, the restricted number of positive MPS cases limits the power of this statistical analysis. The stress-to-rest ratio of the diastolic velocity-time integrals in the patients with three grafted coronary vessels (median 2.3) and in those without preoperative myocardial infarction (median 2.1) were respectively greater than in the patients with two vessels grafted (median 1.7, p < 0.0001) and those with preoperative myocardial infarction (median 1.8, p = 0.0048).


CONCLUSIONS
Dynamic assessment with transthoracic echo-Doppler of a composite arterial graft including the in situ left internal thoracic artery correlates with MPS. In patients with negative MPS, transthoracic echo-Doppler correlates with the myocardial demand.
Gatti
Giuseppe
G
Department of Cardiac Surgery, Villa Torri Hospital, Bologna, Italy. giusep.gatti@tiscali.it
Bentini
Corrado
C
Maffei
Giuseppe
G
Pugliese
Peppino
P
D000368:Aged; D015331:Cohort Studies; D001026:Coronary Artery Bypass / Q000379:methods; D003327:Coronary Disease / Q000000981:diagnostic imaging / Q000601:surgery*; D017548:Echocardiography, Transesophageal; D005260:Female; D005500:Follow-Up Studies; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging*; D006084:Graft Rejection; D006085:Graft Survival; D006801:Humans; D008297:Male; D008875:Middle Aged; D009204:Myocardial Revascularization / Q000379:methods; D011336:Probability; D011446:Prospective Studies; D017534:Radial Artery / Q000637:transplantation*; D011859:Radiography; D011877:Radionuclide Imaging; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D014654:Vascular Patency