ABSTRACT Objective: The internal thoracic artery (ITA) is the conduit of choice for coronary artery bypass grafting (CABG). To avoid spasm of the ITA various topical vasodilators have been suggested either intraluminally or by topical application. In order to describe the best vasodilating agent for preparation of the ITA, a randomized double-blind placebo controlled clinical work was performed in a group of CABG patients. Methods: Three hundred consecutive patients submitted for elective first time coronary artery bypass grafting were randomly subdivided into five groups. The first measurement was performed shortly after the internal thoracic artery was dissected from the chest wall and the second just prior to performing distal anastomosis to the left anterior descending coronary artery. During the time interval between the two measurements topical vasodilator has been injected into the endothoracic fascia of the ITA using the following drugs: papaverine 2 mg/ml, nitrogly-cerin 1 mg/ml, nitroprusside 0.5 mg/ml, mixed solution include sodium nitroprusside (1 mg/ml) and diltiazem (0.5 mg/ml) and normal saline 0.9%. Results: No statistically significant differences were found between the groups in respect to age, body surface area, cardiopulmonary bypass time, cross clamping time, and time interval between the two flow measurements. Mean arterial pressure at the time of the first and second internal thoracic artery flow measurements did not show statistically significant differences either within or between the groups. In all five groups, the free flow of the internal thoracic artery increased significantly with time. However, no statistically significant differences were shown between the five groups with respect to second flow. Conclusions: We suggest that preparation of the ITA by topical vasodilators injection into the endothoracic fascia does not result in a significantly superior free flow than placebo.
Cite this paper
Ozkara, C. , Dogan, O. and Furat, C. (2012) Effect of topical vasodilator on internal thoracic artery blood flow. A placebo-controlled clinical study. World Journal of Cardiovascular Diseases, 2, 204-207. doi: 10.4236/wjcd.2012.23034.
 Loop, F.D., Lytle, B.W., Cosgrove, D.M., Stewart, R.W., Goormastic, M., Williams, G.W., Golding, L.A., Gill, C.C., Taylor, P.C. and Sheldon, W.C. (1986) Influence of the internal mammary graft on 10 year survival and other cardiac events. The New England Journal of Medicine, 314, 1-6. doi:10.1056/NEJM198601023140101
 Lytle, B.W., Loop, F.D., Cosgrove, D.M., Ratliff, N.B., Easley, K. and Taylor, P.C. (1985) Long-term (5-12 years) serial studies of internal mammary artery and saphenous vein coronary bypass grafts. Journal of Thoracic and Cardiovascular Surgery, 89, 248-258.
 Yekeler, I., Pac, M., Kocak, H., Ates, A., Basoglu, A., Ege, E., Reis, A.K. and Ayd?n, M.E. (1993) Atherosclerosis in the internal mammary artery and comparison of the risk factors. Turkiye Klinikleri Journal of Medical Sciences, 11, 89-92.
 Barner, H.B. (1973) Blood flow in the internal mammary artery. American Heart Journal, 86, 570-571.
 Sarabu, M.R., McClung, J.A., Fass, A. and Red, G.E. (1987) Early postoperative spasm in the left internal mammary bypass artery. Annals of Thoracic Surgery, 44, 195-200. doi:10.1016/S0003-4975(10)62041-3
 Green, G.E. (1979) Techniques of internal mammary- coronary artery anastomosis. Journal of Thoracic and Cardiovascular Surgery, 78, 455-459.
 Mills, N.M. and Bringaze, W.L. (1989) Preparation of the internal mammary artery graft: Which is the best method? Journal of Thoracic and Cardiovascular Surgery, 98, 73- 79.
 Jett, G.K., Guyton, R.A., Hetcher, C.R. and Abel, P.W. (1992) Inhibition of human internal mammary artery contractions. Journal of Thoracic and Cardiovascular Surgery, 104, 977-982.
 Sasson, L., Cohen, A.J., Hauptman, E. and Schachner, A. (1994) Effect of topical vasodilators on internal mammary arteries. Annals of Thoracic Surgery, 59, 494-496.
 Nilia, M., Stamlera, A., Sulkesa, J. and Vidne, B.A. (1999) Preparation of the internal thoracic artery by vasodilator drugs: Is it really necessary? A randomized double-blind placebo-controlled clinical study. European Journal Cardio-Thoracic Surgery, 16, 560-563.
 Canzer, C.C. and Dame, N.A. (1994) Ultrasonic assessment of internal thoracic artery graft flow in the revascularized heart. Annals of Thoracic Surgery, 58, 135-138. doi:10.1016/0003-4975(94)91087-1
 Cooper, G.J., Wilkinson, G.A.L. and Angelini, G.A. (1992) Overcoming perioperative spasm of the internal mammary artery. Which is the best vasodilator? Journal of Thoracic and Cardiovascular Surgery, 104, 465-468.
 He, G.W., Rosenfeldt, F.L., Buxton, B.F. and Angus, J.A. (1989) Reactivity of human isolated internal mammary artery to constrictor and dilator agent. Circulation, 80, 141-150.
 Yang, Z. and Lyscher, T.F. (1996) Biological and vasomotor properties of the internal thoracic artery: Role of the endothelium. In: Angelini, G.D, Brian, A.J. and Dion, R., Eds., Arterial Conduits in Myocardial Revascularization, Arnold, 23-31.