Since Murray et al1 reported the feasibility of a systemicto-coronary artery bypass in 1954, many articles have appeared which have described surgical techniques to anastomose the internal mammary artery to the anterior descending or circumflex branch of the left coronary artery by means of nonsuture techniques,2 temporary internal shunts,3 vascular anastomosing staplers,4 or extracorporeal circulation.5 These technical contributions were aimed to improve the patency rate of the coronary artery anastomosis without reference to the physiological background of the coronary circulation.
Coronary bypass inflow is determined by the vascular resistance of the coronary arterial system and the pressure gradient across the anastomosis. If the coronary vascular resistance is constant, the pressure gradient will determine the inflow. It is known that pulsatile pressure contours change as they propagate along the aorta.6 There is also a time lag of pulse wave propagation between the aortic root and
Wakabayashi A, Beron E, Lou MA, Mino JY, da Costa IA, Connolly JE. Physiological Basis for the Systemic-to-Coronary Artery Bypass GraftInadequacy of the Internal Mammary Artery for This Purpose and Appraisal of the Ascending Aorta as Its Proximal Site. Arch Surg. 1970;100(1):17-19. doi:10.1001/archsurg.1970.01340190019006