Early Development of Surgical Treatment for Aortic Aneurysms

Aortic aneurysms have challenged the medical profession for centuries, and the history of surgical therapies reveals the ingenuity of early physicians and surgeons in treating these lesions. Most of those attempts were fruitless, frustrating, and disappointing. During my medical education and surgical training, there was a shift from indirect or palliative methods to a direct, curative approach to these lesions. I remember the introduction of wire into aneurysms to promote thrombosis and the application of cellophane or fibrosing agents to reinforce the wall. I also recall the insanity and trepidation that surgeons experienced in approaching such lesions, especially when rupture was threatening.

While I was a resident at Johns Hopkins in 1949 and 1950 (Fig. 1), I had several personal experiences in treating aneurysms. In one, I was assisting Dr. Grant Ward (Fig. 2) in removing an infected metallic prosthesis, which he had devised and implanted after resecting an osteochondral sarcoma of the manubrium. As the prosthesis was forcefully withdrawn from the sternum, a sudden gush of blood spewed from an underlying pseudoaneurysm. Dr. Ward suffered from brachial plexus paralysis secondary to syringomyelia, and he wore a shoulder splint that partially disabled his right arm. However, he quickly thrust his left hand and index finger into the opening to control the bleeding from the pseudoaneurysm. After our initial alarm subsided, he informed me that I would need to repair the lesion because he was helpless. Somehow, I successfully repaired the ascending aorta with a patch of pectoralis muscle, and the patient survived.

Fig. 1 Residents in cardiovascular surgery at Johns Hopkins Medical School, 1950. Dr. Cooley is in the front row, directly to Dr. Blalock's left.

Fig. 2 Grant E. Ward, MD

In another experience, a patient of Dr. Alfred Blalock's developed a large, painful aneurysm in the right side of the mediastinum about 3 months after an operation to repair coarctation of the aorta. During that operation, Dr. Blalock (Fig. 3) had excised the coarcted segment and repaired the aorta with an end-to-end anastomosis. Since Dr. Blalock was now serving as a visiting professor in Hawaii, it befell me as senior resident to attempt repair. I accomplished the repair through a “trap door” sternotomy, with an intercostal and supraclavicular approach. The lesion was excised by ligating the subclavian artery proximally and distally, and the patient recovered without complications.

Fig. 3 Alfred Blalock, MD

These favorable experiences caused me to realize that direct treatment of aortic aneurysms was possible. After I joined the faculty at Baylor College of Medicine with Dr. Michael DeBakey, I saw a patient during rounds one day who had a large syphilitic aneurysm of the innominate artery; the aneurysm was eroding through the chest wall and threatened rupture. Using an approach similar to the one above, I occluded the base of the aneurysm with a large Crafoord clamp. The lesion was opened, the distal common carotid and subclavian arteries were ligated, and the aortic opening was sutured. This technique, reported as tangential excision and aortorrhaphy (Fig. 4), became the recommended treatment for sacciform aneurysms in the thoracic aorta. ¹

Fig. 4 Partial title page of “Surgical Considerations of Intrathoracic Aneurysms of the Aorta and Great Vessels,” as reprinted from the Annals of Surgery (1952).

I recall writing to Dr. Blalock about my belief that aortic aneurysmectomy was not only possible but, in my opinion, the procedure of choice for these lesions. He said that he would discuss the matter with Dr. Henry Bahnson, who later reported his spectacular experience with the new concept. In 1951, we presented the first 6 cases (including my first 2 cases at Hopkins) before the Southern Surgical Association. ¹ Five of the first 6 patients had syphilitic aneurysms. I can readily recall the comment of the renowned Dr. Evarts Graham of Barnes Hospital. He said that the technique, unfortunately, was untimely because the advent of penicillin would make aortic syphilitic aneurysms rare. That was true, but atherosclerosis and trauma soon provided an abundance of pathologic material for clinical trials.

In critical locations, such as the ascending aorta and transverse arch, temporary circulatory arrest was needed to enable the surgeon to complete the repair. This was especially true for fusiform aneurysms. Some ingenious and tedious procedures, using temporary shunts, were devised to give surgeons time to resect such lesions, and we were successful in a few cases. With the advent of temporary cardiopulmonary bypass and especially of induced hypothermia, which permitted complete circulatory arrest, all regions of the aorta became accessible for repair. Ischemic injury to the brain and spinal cord remain a threat to the success of any aortic repair, and volumes of literature have been amassed on experiences and on techniques for preventing these complications. Countless adjuncts have been tried, including pharmacologic agents and spinal fluid drainage.

For those early procedures, synthetic grafts were not available for replacing the resected aortic segments. In 1945, Gross and Hufnagel ^2,3 of Boston used homografts to repair thoracic coarctation, and in the early 1950s, Oudot ⁴ and Dubost and colleagues ⁵ in France first reported using preserved homografts to replace the resected segment of abdominal lesions. We collected our own grafts, at first preserving them in antibiotic and other media at low temperatures. Subsequently, tissue lyophilization was introduced, ⁶ and surgeons were soon using freeze-dried grafts extensively. Unfortunately, the durability of freeze-dried grafts was unpredictable. Synthetic grafts were needed, and industry produced by introducing new fibers for fabric grafts, including nylon, vinyon, Teflon, and Dacron (polyester). These new fibers were used to fabricate tube grafts of all sizes. Durability was a problem, however, and some fibers, such as nylon, deteriorated quickly. Teflon did not form a strong bond with surrounding tissues. Polyester proved best. Variations in textile processing were also problems in the early days, as fabric grafts with too high a porosity often led to serious intraoperative bleeding. Improvements in fabrication, along with application of substances such as collagen, gelatin, and fibrin to seal the interstices of the grafts, have provided surgeons with grafts that are tissue-compatible, durable, hemostatic, and easy to tailor. We are indebted to our colleagues in industry who have listened to us, then improved the fabrics to meet our needs.

Surgical repair of aortic aneurysms remains an important aspect of cardiovascular surgery. Today, the emphasis is on preventing rupture and restoring vascular continuity—a concept called endoaneurysmorrhaphy, which was described more than a century ago by Rudolph Matas. ⁷ Today, our profession is engaged not only in the aortic repair procedures that surgeons of my generation pioneered, but in interventional repairs that are done by limited-access approaches and that use balloons, stents, fabrics, plastics, and various devices to restore vascular continuity. Thus, the evolution of vascular and aortic procedures promises to continue, as newer generations take over the challenges.