Dr. Blalock approached the problem of coarctation of the aorta after an almost casual mention of the problem by Dr. Edwards A. Park. Several months later Dr. Park was greatly surprised to find a complete manuscript of "The Surgical Treatment of Experimental Coarctation (atresia) of the Aorta"23 on his desk with himself listed as co-author. He asked to have his name removed, but the Professor would not listen to him.
Coarctation (constriction) of the aorta is a condition that leads to severe hypertension in the head and arms and ultimately death from heart failure or stroke. It is an isolated congenital malformation; that is, it usually does not occur in association with other congenital malformations of the heart and/or great vessels. It is most frequently located just distal to the arch of the aorta at about the level of the ductus ligament, but may occur proximal or distal to this point. The problem was how to get more blood beyond this point of constriction to the lower part of the body and lower extremities. We made numerous attempts to produce a chronic constriction of the aorta. Being unsuccessful in these attempts, Dr. Blalock decided that I should divide the aorta to actually produce atresia and then span the gap in the circulation by using the left subclavian artery (see figs. 12, 13).
In an end-to-end anastomosis, the eversion of the edges of the vessels is accomplished by a relatively simple placement of sutures. By using three stay sutures, triangulating and apposing the ends of the vessels, the operator may rotate the vessels so that any segment of the suture line may be made the anterior segment, and any segment brought into full view. This was the technique we had used in the transplantation of organs and in the divided subclavian artery to divided pulmonary artery anastomoses.
For this end-to-side anastomosis, the vessels could not be rotated, the aorta being in a fixed position. The posterior segment of the anastomosis had to be dealt with in situ. It was impossible to visualize the suture from the outside of the vessels due to the fact that the two vessels were running in precisely opposite directions. Placing a continuous everting mattress suture and tightening each stitch as placed was awkward, time consuming, and difficult. I tried taking several stitches before tightening and it worked. Thus, the technique of placing a continuous everting mattress suture loosely across the posterior one-third of the suture line was developed. Putting tension on both ends of the suture material simul-