Cor Vasa 2007, 49(6):216-221 | DOI: 10.33678/cor.2007.079

Comparison of intraoperative flow rates in the composite arterial Y graft and in the left internal thoracic artery together with venous grafts used for revascularization of the left coronary artery region

Petr Němec^*, Vilém Bruk, Marek Gwozdziewicz, Andrea Steriovský, Martin Šimek, Petr Šantavý, Martin Troubil, Marián Benčat

Kardiochirurgická klinika, Fakultní nemocnice Olomouc a Lékařská fakulta Univerzity Palackého, Olomouc, Česká republika

Aim:
The aim of the study was to assess the intraoperative flow rates in the arterial Y graft used for revascularization of the left coronary artery region and to compare them with the flow rates obtained by conventional revascularization using the left internal thoracic artery (LITA) and vein grafts.

Methods:
Three hundred patients were divided into two groups: Group A undergoing arterial revascularization with both internal thoracic arteries used as a Y graft, and Group B undergoing conventional revascularization using the LITA attached to the left anterior descending artery (LAD) and venous grafts to the other branches of the left coronary artery. Flow measurements were performed as follows: 1. In situ ITA at the beginning of the dissection. 2. After termination of the dissection, 3. Before the start of the peripheral anastomosis, 4. After termination of the peripheral anastomosis with the aortic clamp in place, 5. After release of the clamp, and 6. Prior to completion of surgery. In all the patients, analysis of the cardiac enzymes was performed.

Results:
The flow rate in the skeletonized LITA in Group A was higher than that in the pedicled one in Group B, being 31.1 ± 1.6 ml/min and 26.7 ± 1.3 ml/min, respectively, p < 0.05 at the end of the procedure. The flow rate in the right ITA (26.6 ± 1.5 ml/min) was significantly lower than in venous grafts (71.0 ± 3.7), p < 0.05. The cumulative flow rates at the end of the operation were 58.7 ± 2.0 ml/min in Group A (arterial Y graft) and 97.3 ± 4.2 ml/min (p < 0.05) in Group B (conventional technique). The calculated flow reserve was 2.0 in Group A and 2.4 in Group B. Postoperative troponin T (TnT) levels were higher in Group B due to the higher number of patients with postoperative myocardial ischemia.

Conclusion:
Based on our results, we documented the utility of the arterial Y graft constructed from both ITAs. This graft has sufficient flow rates at rest and, also, a sufficient flow reserve even though both parameters were lower compared with conventional revascularization. Its proper function was confirmed by clinical results and postoperative TnT levels. Therefore, use of the Y graft can be recommended for revascularization of the left coronary artery region.

Keywords: Blood flow measurement; Coronary bypass graft; Arterial Y graft

Published: June 1, 2007  Show citation