Blood Flow Pattern and Anastomotic Compliance for Interrupted versus Continuous Coronary Bypass Grafts


  • Marc Gerdisch
  • Thomas Hinkamp
  • Stephen D. Ainsworth



Background: Use of the interrupted coronary anastomosis has largely been abandoned in favor of the more rapid continuous suturing technique. The Coalescent U-CLIP anastomotic device allows the surgeon to create an interrupted distal anastomosis in the same amount of time that it would take to create a continuous anastomosis. This acute bovine study examined the effect of the anastomotic technique on blood flow and vessel wall function.

Methods: End-to-side coronary anastomoses were created in an open chest bovine model using the left and right internal thoracic arteries and the left anterior descending coronary artery. All other variables except suturing technique were carefully controlled. In each animal, one anastomosis was completed using a continuous suturing technique and the other was performed in an interrupted fashion using the Coalescent U-CLIP anastomotic device. Volumetric flow curves through each graft were analyzed using key indicators of anastomotic quality, and anastomotic compliance was evaluated using intravascular ultrasound. Luminal castings were created of each vessel to examine the interior surface of each anastomosis for constrictions and deformities.

Results: The interrupted anastomoses created with the Coalescent U-CLIP anastomotic device showed significant differences with respect to anastomotic compliance, pulsatility index, peak flow, and percentage of diastolic flow. The cross-sectional area and degree of luminal deformity were also different for the two suturing techniques.

Conclusions: In this acute bovine model, interrupted coronary anastomoses demonstrated superior geometric consistency and greater physiologic compliance than did continuously sutured anastomoses. The interrupted anastomosis also caused fewer disturbances to the flow waveform, behaving similarly to a normal vessel wall. The combination of these effects may influence both acute and long-term patency of the coronary bypass grafts.


Berdat PA, Kipfer B, Immer FF, Pfammatter JP, Carrel T. 2002. Facilitated vascular interrupted anastomosis in cardiovascular surgery with a new clip device. J Thorac Cardiovasc Surg 124:1256-8.nCaskey MP, Kirshner MS, Alderman EL, Hunsley SL, Daniel MA. 2002. Six-Month angiographic evaluation of beating-heart coronary arterial graft interrupted anastomoses using the Coalescent U-CLIP anastomotic device: a prospective clinical study. Heart Surg Forum 5:319-27.nD'Ancona G, Karamanoukian HL, Ricci M, Schmid S, Bergsland J, Salerno TA. 2000. Graft revision after transit time flow measurement in off-pump coronary artery bypass grafting. Eur J Cardiothorac Surg 17:287-93.nHill AC, Maroney TP, Virmani R. 2001. Facilitated coronary anastomosis using a nitinol U-Clip device: bovine model. J Thorac Cardiovasc Surg 121:859-70.nKlein SR, Goldberg L, Miranda RM, Bosco P, Nelson RJ, White RA. 1982. Effect of suture technique on arterial anastomotic compliance. Arch Surg 117:45-7.nLoop FD. 1979. Technique for performance of internal mammary artery-coronary artery anastomosis. J Thorac Cardiovasc Surg 78:460-3.nLoop FD, Lytle BW, Cosgrove DM, et al. 1986. Influence of the internal-mammary-artery graft on 10-year survival and other cardiac events. N Engl J Med 314:1-6.nMack MJ, Magovern JA, Acuff TA, et al. 1999. Results of graft patency by immediate angiography in minimally invasive coronary artery surgery. Ann Thorac Surg 68:383-9; discussion 389-90.nMorinaga K, Okadome K, Kuroki M, Miyazaki T, Muto Y, Inokuchi K. 1985. Effect of wall shear stress on intimal thickening of arterially transplanted autogenous veins in dogs. J Vasc Surg 2:430-3.nOjha M, Leask RL, Johnston KW, David TE, Butany J. 2000. Histology and morphology of 59 internal thoracic artery grafts and their distal anastomoses. Ann Thorac Surg 70:1338-44.nShioi, K, Washizu T, Kawamura M, Abe T, Iyomasa Y. 1984. A study of sequential anastomoses in aortocoronary bypass surgery--internal configuration by the casting injection technique. Thorac Cardiovasc Surg 32:18-22.nSottiurai VS, Yao JS, Batson RC, Sue SL, Jones R, Nakamura YA. 1989. Distal anastomotic intimal hyperplasia: histopathologic character and biogenesis. Ann Vasc Surg 3:26-33.nTozzi P, Hayoz D, Ruchat P, et al. 2001. Animal model to compare the effects of suture technique on cross- sectional compliance on end-to-side anastomoses. Eur J Cardiothorac Surg 19:477-81.nBallyk PD, Walsh C, Butany J, Ojha M. 1998. Compliance mismatch may promote graft artery intimal hyperplasia by altering suture-line stresses. J Biomech 31:229-37.nVanHimbergen DJ, Koenig SC, Jaber SF, Cerrito PB, Spence PA. 1999. A review of transit-time flow measurement for assessing graft patency. Heart Surg Forum 2:226-9.nWalpoth BH, Bosshard A, Genyk I, et al. 1998. Transit-time flow measurement for detection of early graft failure during myocardial revascularization. Ann Thorac Surg 66:1097-100.nWolf RK, Alderman EL, Caskey MP, et al. 2002. Interrupted anastomoses using a self-closing clip device: a multi-center prospective clinical trial. Presented at the 82nd Annual Meeting of the American Association for Thoracic Surgeons; May 5-8, 2002; Washington, DC, USA.nYoung JN, MacMillan JC, May IA, Iverson LI, Ecker RR. Internal configuration of saphenous-coronary anastomoses as studied by the cast-injection technique. J Thorac Cardiovasc Surg 75:179-85.n



How to Cite

Gerdisch, M., Hinkamp, T., & Ainsworth, S. D. (2005). Blood Flow Pattern and Anastomotic Compliance for Interrupted versus Continuous Coronary Bypass Grafts. The Heart Surgery Forum, 6(2), 65-71.