Ascending Aortic Associated Aortic. Aneurysms with Regurgitation. Koger K. Stenlund, M.D., Charles K. Peterson, M.D.

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1 Ascending Aortic Associated Aortic Aneurysms with Regurgitation Hovald K. Helseth, M.D., John J. Haglin, M.D., Koger K. Stenlund, M.D., Charles K. Peterson, M.D., and David W. Gauger, M.D. ABSTRACT A safe method for replacement of the entire aortic valve, root, and ascending aorta for aortic insufficiency associated with an ascending aortic aneurysm is supported. This method utilizes a composite synthetic graft and valve with direct annular suture and implantation of the coronary arteries in the graft. The advantages of the technique include a shortened operation and freedom from postoperative hemorrhage, paraprosthetic leakage, and recurrent aneurysm formation. A neurysmal dilatation of the ascending aorta may be caused by cystic medial necrosis, syphilis, atherosclerosis, idiopathic dilatation of the aorta, and giant cell aortitis. Involvement of the aortic root in the aneurysmal dilatation in any of these diseases may lead to failure of apposition of relatively normal valve cusps and give rise to symptomatic aortic regurgitation. Surgical management which fails to consider the pathological process in the aortic root will carry a higher mortality and increased long-term morbidity. With widespread use of cardiopulmonary bypass, early partial excision and banding of aneurysms of the ascending aorta has generally given way to direct aneurysm resection with aortic valve replacement. Several approaches to this problem have been utilized. Bentall and DeBono 4 in 1968 presented a method of handling the aortic valve, root, and ascending aorta that includes suture of a composite prosthetic valve and graft directly to the annulus with implantation of the coronary ostia to the graft. The advantages of this technique are emphasized in the following report. Case Histories Patient 1. A 56-year-old woman was hospitalized for pancreatitis. A cardiac diastolic murmur was heard, and she gave a history of increasing shortness of breath, tiredness, and substernal discomfort. The blood pressure was 150/45 mm. Hg with a regular pulse of 80. The chest roentgenogram From the Departments of Surgery, Cardiology, and Pathology of the Hennepin County General Hospital, and the St. Louis Park Medical Center, Minneapolis, Minn. Accepted for publication June 1, 19i3. Address reprint requests to Dr. Helseth, Hennepin County Genci-a1 Hospital, Fifth and Portland Sts. S., Minneapolis, Minn THE ANNALS OF THORACIC SURGERY

2 Aneurysms with Aortic Regurgitation revealed a considerable increase in the size of the ascending aorta over previous films and some enlargement of the cardiac silhouette. Serological tests for syphilis were negative. Cardiac catheterization and aortography revealed a left ventricular end-diastolic pressure of 25 mm. Hg and a large ascending aortic aneurysm with moderate (2 to 3 +) aortic regurgitation. The patient underwent composite valve and graft replacement with a No. 10 Starr-Edwards valve and a 30 mm. Dacron prosthesis. The aortic valve cusps appeared normal and were not excised. The coronary arteries were implanted into the Dacron graft. The postoperative course was free from complication. Bleeding was minimal, and the chest catheters were removed on the second postoperative day. She was discharged on the eighth day with coumadin anticoagulation. Follow-up visits have shown that she is asymptomatic with a blood pressure of 118/76 mm. Hg, a negative plasma hemoglobin, and considerable reduction in size of the heart and mediastinum. Microscopical sections of the aneurysm showed moderately severe atherosclerosis. Patient 2. A 66-year-old farmer had had detectable aortic valve murmurs and a large aorta for several years but had remained asymptomatic until several months prior to operation, when severe congestive heart failure required hospitalization and the use of digitalis and diuretics. At the time of surgical consultation he was able to work part-time with very occasional angina and some shortness of breath on exertion. By history there had been an unknown and prolonged febrile illness several years before. The patient had lost 30 pounds in weight over the previous six months. Blood pressure was 160/45 mm. Hg and the pulse was 70 and regular. There was a palpable diastolic thrill over the apex and a grade 4/6 diastolic murmur along the left sternal border. The murmur could be heard over the peripheral arteries as well. The chest roentgenogram showed cardiomegaly, aneurysmal aortic dilatation, and pulmonary congestion. An aortogram revealed severe aortic regurgitation (3 to 4 +) with aneurysmal dilatation of the entire thoracic aorta that was more pronounced in the ascending aorta. Coronary angiography showed the right coronary artery to be normal; the left could not be entered. From the aortogram, the left coronary artery filled partially and appeared normal. The patient underwent composite replacement of the ascending aorta and implantation of the coronary arteries into the graft. A 29 mm. Bjork prosthesis and a 35 mm. Dacron graft were used. The postoperative course was uncomplicated. The chest catheters were removed on the second postoperative day, and the patient was discharged the tenth day on coumadin. When he was seen at early follow-up the blood pressure was 124/80 mm. Hg and the pulse was regular at 76. The patient was well, and the VOL. 16, NO. 4, OCTOBER,

3 HELSETH ET AL. pulmonary congestion had diminished. The cardiac silhouette and ascending aorta were normal on chest roentgenogram. Sections of the resected portion of the aorta showed giant cell (granulomatous) aortitis. Prominent microscopical features were present within the media, where numerous focal accumulations of multinucleated giant cells surrounded by inflammatory cells were seen. Elastic staining revealed focal disruption of elastic fibers of the media in these areas. The vasa vasorum were patent without endarteritis. Intimal involvement was absent. Technique The operative technique is illustrated.in the Figure. After institution of cardiopulmonary bypass, the aorta is clamped at the brachiocephalic trunk and the aneurysm opened longitudinally and left in place (Figure, a, b). //k c artery perfusion Operative technique. (a, 6) The aneurysm is opened longitudinally. (c) Sutures including the valve cusps are placed through the prosthetic valve skirt and Dacron graft while coronary perfusion continues. (d) Catheters are placed through the graft, decompressing the left ventricle and perfusing the left coronary artery while the right coronary ostium is sutured to the graft. (e) The distal anastomosis is completed. (f) The aneurysm wall is sutured around the composite graft. (LC = left coronary artery; RC = right coronary artery; LV = left ventricle.) 370 THE ANNALS OF THORACIC SURGERY

4 Aneurysms with Aortic Regurgitatioll Separate right and left coronary artery perfusion is established. An appropriate valve and Dacron prosthesis are selected, and the valve is sutured to the inside of the Dacron graft (Figure, c). Simultaneously sutures are placed around the annulus incorporating the valve cusps, which can usually be left in place. The sutures are placed through the valve skirt and graft in order to secure both to the aortic annulus as a single unit (Figure, c). A small opening in the anterior wall of the graft allows a catheter to lie across the prosthetic valve to decompress the left ventricle. Circular openings in the graft are excised adjacent to the coronary ostia, and each is sutured to the graft with continuous suture. When the posterior row of the coronary anastomosis is completed, the coronary perfusion cannula is brought through the anterior wall of the graft to continue coronary perfusion as the anterior portion of the coronary anastomosis is completed (Figure, d). The low-profile disc valve (Bjork) used in the second patient allowed more space in the aortic root for manipulation of coronary catheters and permitted the catheters to be brought directly through the anterior wall of the graft for easy placement into the coronary arteries, thereby preventing any interference with the distal anastomosis. The lowprofile valve also avoided interference of valve cage struts with the coronary artery implantation. The heart is elevated in the pericardial sac and the distal graft-to-aorta anastomosis is made, inverting the graft into the aorta (Figure, e). The heart is defibrillated and bypass discontinued as the cardiac output improves. With bleeding controlled the aneurysm wall is then trimmed and wrapped tightly around the prosthetic graft to complete the procedure (Figure, f). Comment The majority of aneurysms of the ascending aorta result from cystic medial necrosis. Giant cell aortitis, once called chronic diffuse mesoarteritis, is rare but has been associated with aortic regurgitation and has led to aneurysmal dilatation and dissection of the aorta [I, 10, 111. Regardless of the etiology, once an aneurysm becomes associated with aortic regurgitation, serious thought must be given to valve replacement. A continued wide pulse pressure may have an adverse effect on the aorta, possibly increasing the likelihood of enlargement and rupture as well as the chance of acute dissection. The aortic regurgitation may result in congestive heart failure. The presence of an ascending aortic aneurysm with aortic regurgitation continues to be a formidable surgical challenge. The potential problems include prolonged cardiopulmonary bypass, postoperative hemorrhage, persistent aneurysm of the aortic root, damage to the coronary arteries, and aortic valve incompetence. Cooley and DeBakey and their associates [S, 61 reported a large experience with graft replacement distal to the coronary arteries. Groves and VOL. 16, NO. 4, OCTOBER,

5 HELSETH ET AL. his associates [9] first emphasized the importance of valve replacement because of dilatation of the annulus. This was combined with graft replacement distal to coronary ostia. Several authors have written on this method [l, 3, 4, 8, 131, but the complication rate remains quite high and does not deal directly with that area of aorta between the annulus and the coronary ostia (the aortic root). In the report by Bloodwell, Hallman, and Cooley [3] the incidence of reoperation was 12y0. Similarly, the hospital mortality in Groves [9] series was 36y0, with another 14y0 dying subsequent to discharge; 3 patients had significant bleeding that contributed to death. Many efforts have been made to control bleeding from what is often a friable aorta [3, 5, 131. Another potential problem in long-term survivors is the recurrence of aneurysm in the aortic root not excised. Resection of the entire area of disease has been the aim of surgeons for many years, but concern over the coronary arteries has kept most resections distal to the aortic root. Wheat, Wilson, and Bartley [15] in 1964 emphasized the need to resect the entire aneurysm and root. They did so by leaving the coronary ostia attached to the annulus by tongues of aortic wall. Following valve replacement the prosthetic graft was sutured to the annulus, incorporating the areas of aortic wall containing the coronary arteries. A recent collection of 13 patients so treated show a one-month mortality rate of 30y0. Of the early survivors, 5 of 11 bled excessively and 2 (18%) required reoperation [14]. This extended dissection therefore still poses problems with hemorrhage, paravalvular leakage, and possible residual aneurysm formation in that portion of aorta containing the coronary ostia. In those aneurysms which widely displace the coronary arteries, Groves and his colleagues [9] were tempted to implant the coronary arteries, with a small cuff of aorta, directly to a graft sewn to the annulus. They had not seen such an aneurysm, however, and the procedure was considered radical. There are several advantages of the composite valve and graft technique presented by Bentall and associates [2, 121 and utilized by Edwards and Kerr [7]. The entire disease process of the aortic rodt is eliminated, and the likelihood of recurrence is minimized. Paraprosthetic leakage is no longer a problem after composite suture of the graft and valve. Also, the secure proximal annular suture line reduces the threat of postoperative hemorrhage, which is commonly fatal. Generally, the distal suture line is made in more normal aortic tissue and is very amenable to reinforcement. The technique reduces bypass time over the more tedious method of Wheat and associates [15]. Coronary artery perfusion can continue without significant interruption until the aortic cross-clamp is released, and coronary artery implantation has presented no difficulty. Should the ostia not be greatly displaced, a smaller composite graft could be used. No evidence of myocardial ischemia or arrhythmia suggesting compromise of coronary blood flow has developed THE ANNALS OF THORACIC SURGERY

6 Aneurysms with Aortic Regurgitation In conclusion, a surgical approach that appeared radical initially now offers the most direct and definitive correction for the problem of aneurysm with aortic regurgitation. Fortunately, the method offers these advantages with reduced operative morbidity and mortality. References 1. Austen, W. G., and Blennerhassett, J. B. Giant cell aortitis causing an aneurysm of the ascending aorta and aortic regurgitation. N. Engl. J. Med. 272:80, Bentall, H., and DeBono, A. A technique for complete replacement of ascending aorta. Thorax 23:338, Bloodwell, R. D., Hallman, G. L., and Cooley, D. A. Aneurysm of the ascending aorta with aortic valvular insufficiency. Arch. Surg. 92:588, Cooley, D. A., Bloodwell, R. D., Hallman, G. L., and Jacobey, J. A. Aneurysm of the ascending aorta complicated by aortic valve incompetence: Surgical treatment. J. Cardiovasc. Surg. (Torino) 8: 1, Cooley, D. A., and DeBakey, M. E. Resection of entire ascending aorta in fusiform aneurysms using cardiac bypass. J.A.M.A. 162: 1158, DeBakey, M. E., Cooley, D. A., Crawford, E. S., and Morris, G. C., Jr. Aneurysms of the thoracic aorta: Analysis of 179 patients treated by resection. J. Thorac. Surg. 36:393, Edwards, W. S., and Kerr, A. R. A safer technique for entire replacement of the ascending aorta and aortic valve. J. Thorac. Cardiovasc. Surg. 59:837, Gerbode, F., Semb, G. S., Hill, J. D., and Kerth, W. J. Aneurysms of the ascending aorta: A method of reconstructing the aortic root. Ann. Thorac. Surg. 2:525, Groves, L. K., Effler, D. B., Hawk, W. A., and Gulati, K. Aortic insufficiency secondary to aneurysmal changes in the ascending aorta: Surgical management. J. Thorac. Cardiovasc. Surg. 48:362, Kent, D. C., and Arnold, H. Aneurysm of the aorta due to giant-cell aortitis. J. Thorac. Cardiovasc. Surg. 53:572, Reid, J. V. 0. Dilatation of the aorta due to granulomatous (giant-cell) aortitis. Er. Heart J. 19:206, Singh, M. P., and Bentall, H. H. Complete replacement of the ascending aorta and aortic valve for the treatment of aortic aneurysm. J. Thorac. Cardiovasc. Surg. 63:218, Trinkle, J. K., Mobin-Uddin, K., and Bryant, L. R. Primary anastomosis of aneurysms of the ascending aorta caused by cystic medial necrosis. J. Thorac. Cardiovasc. Surg. 62:281, Wheat, M. W., Jr., Boruchow, J. R., and Ramsey, H. W. Surgical treatment of aneurysms of the aortic root. Ann. Thorac. Surg. 12:593, Wheat, M. W., Jr., Wilson, J. R., and Bartley, J. D. Successful replacement of the entire ascending aorta and aortic valve. J:A.M.A. 188:717, Addendum Since this paper was prepared, 2 additional patients with cystic medial necrosis and aortic regurgitation have been handled in this manner. A 65-year-old man underwent the composite graft procedure using a lowprofile valve. In addition, a saphenous vein bypass graft was placed from the prosthetic graft to the left anterior descending coronary artery. His postoperative course was uncomplicated, and he was discharged at ten days. VOL. 16, NO. 4, OCTOBER,

7 HELSETH ET AL. A 62-year-old man, hospitalized for four weeks with acute and chronic heart failure and renal failure, was operated upon. He had a circumferential ascending aortic dissection with prolapse of the aortic root that was causing severe regurgitation. It was elected to utilize the technique discussed here in spite of the absence of an aneurysm of the ascending aorta. The lack of dilatation of the aortic root and the friability of the aortic dissection resulted in the operation being difficult and time-consuming. The patient did not have excessive bleeding postoperatively, and following six weeks of hemodialysis he had complete renal and cardiac recovery. He was discharged seven weeks following operation. It would have been preferable to reconstruct the aortic dissection alone or to use a smaller composite graft. 374 THE ANNALS OF THORACIC SURGERY