Perioperative spasm of the internal mammary artery (IMA) may result in early restriction of bypass flow. Therefore, pharmacological pretreatment is usually suggested. We present a technique of temporary distal occlusion of the transsected IMA using a metal clip. After 1 hour of storage in normal saline (SAL) there were significantly better flow rates compared with proximal application of a bull-dog clamp. No further increase in flow was noticed after submersion of the IMA pedicle in verapamil (VER). This technique easily provides sufficient IMA flow at the time of anastomosis, probably due to continuous endoluminal dilatation of the IMA by blood pressure, and thus avoids pharmacological pretreatment with vasodilators.
Wittwer, T., Wahlers, T., Franke, U., & Haverich, A. (1998). Temporary distal occlusion for non-pharmacological preconditioning of harvested internal mammary artery grafts. European Journal of Cardio-Thoracic Surgery, 13(3), 332–333. https://doi.org/10.1016/S1010-7940(98)00015-3