M niques used in patients requiring concomitant replacement

Transcription

1 Composite Valve-Graft Replacement of Aortic Root Using Separate Dacron Tube for Coronary Artery Reattachment Joseph S. Coselli, MD, and E. Stanley Crawford, MD Department of Surgery, Baylor College of Medicine and The Methodist Hospital, Houston, Texas Traditional techniques of aortic root replacement have consisted of separate valve and graft replacement or use of a composite valve graft. These methods have been associated with problems including hemostasis, suture line disruption, and pseudoaneurysm development. They have had limited application in patients without sinus segment enlargement and acute aortic dissection. Between May 21, 1986, and September 7, 1988, 90 patients (73 male and 17 female) underwent replacement of the aortic valve and ascending aorta using a composite valve graft with reattachment of the coronary ostia using a separate, smaller (10 mm) Dacron tube graft. Aortic root replacement was done alone in 41 patients (46%), in association with a concomitant cardiac procedure in 26 patients (29%), and iin 23 patients (26%) undergoing cardiac reoperation with and without a concomitant procedure. Aortic arch replacement was required in 25 patients (28%). Profound hypothermia and circulatory arrest were employed in 29 patients (32%). Early survival was 91% (82/90), and there were 4 late deaths. The procedure was found to be hemostatic (only 4 patients [4% I required reexploration for hemorrhage) and durable (no reoperation for pseudoaneurysm formation was necessary). (Ann Tllorac Surg 1989;47:558-65) ajor advances have been made in the surgical tech- M niques used in patients requiring concomitant replacement of the aortic valve, tubular ascending aorta, and coronary sinus segment. Composite valve-graft replacement became a practical consideration with the operation described in 1968 by Bentall and DeBono [l] and later by Edwards and Kerr 121, which involved direct reattachment of the coronary artery origins to openings in an intraoperatively constructed valve-graft conduit. This is probably the most commonly utilized technique today for aortic root replacement. An alternative approach has been championed by others [3, 41. In this approach, the supraannular portion of the sinus segment around the coronary arteries is preserved, and a separate valve and tube graft are inserted. Problems encountered with these conventional techniques have been bleeding from the sites of reattached coronary artery origins, coronary artery distortion, and late development of pseudoaneurysms. These problems have been attributed to friable inadequate aortic tissue, particularly in the presence of Marfan syndrome, and to suture lines that are either under tension or inaccessible. Application of conventional methods is often limited in patients requiring aortic root replacement in the setting of acute aortic dissection in whom there has not been prior aortic dilation and in those undergoing cardiac reoperation. In 1978, Cabrol and associates [5] introduced an alter- Presented at the Thirty-fifth Annual Meeting of the Southern Thoracic Surgical Association, Marco Island, FL, Nov 10-12, Address reprint requests to Dr Crawford, 6535 Fannin, M.S Houston, TX native to direct coronary artery reattachment to a composite graft by employing a separate, smaller, transversely placed tube graft. In this report we present our experience with modifications of this latter technique in 90 patients who underwent aortic root replacement. Material and Methods Pa tien t Population Between May 21, 1986, and September 7, 1988, 283 patients required repair or replacement of the ascending aorta or aortic arch. A pitch or primary repair was used in 13 (5%), simple graft Ieplacement in 101 (36%), and a separate valve and graft in 60 (21%). A composite valve graft was employed in 109 (39%). In this last group, the coronary arteries were reconstituted by saphenous vein grafts in 5 and by direct reattachment using a button of aortic wall in 14 patients. A separate, smaller Dacron tube graft was used for coronary artery reattachment in 90 patients, and the technique and results of operation in these 90 patients constitute the material of this report. There were 73 male p3tients (81%) with an average age of 51 years (range, 11 to 76 years) and 17 female patients (19%) with an average age of 43 years (range, 14 to 70 years). Operation was undertaken in 31 patients (34%) who had aortic dissection; acute dissection was present in 7 and chronic dissection in 24. In 59 patients (66%) there was medial degenerative disease without dissection. Sufficient clinical stigmata were present in 22 patients (24%) to classify them as having Marfan syndrome. Isolated composite valve-graft replacement of the aortic root was employed in 41 patients (46%) (Fig 1). Chronic by The Society of Thoracic Surgeons /89/$3.50

2 Ann Thorac Surg 1989; COSELLI AND CRAWFORD 559 Fig 2. Draroiirg arid nortograin of patient after operation using a modijcnfioii oj the procedure of Cabrol and co-workers [51. The transverse coronnr!/ artery graft is ioidely patent, and the lesion in the left anterior desceiidiri<y coronary arter!! has been Iypssed with the lejf internal rriartiirinry artery. B Fig 2. (A) Drawing and aortograrn of patient with bicuspid aortic valve, aortic valve insufficiency, chronic dissection, and arieur!/sm of the ascending aorta. Note previous graft replacetnent for coarctation. (B) Drarciing and aortogram tirade after operation itsirig a rnodificatiori of the procedure of Cabrol arid co-workers (51 for aortic root replacetiienf. chronic aortic dissection and 3, acute dissection. Profound hypothermia and circulatory arrest were employed in 14 patients having primary operation for aortic arch replacement and in 15 patients having a repeat operation to replace the arch and/or to minimize difficult or hazardous dissection. The reason for reoperation varied with the type and extent of the original procedures (Table 2). Two patients had undergone previous composite valve-graft replacement using the Bentall technique. A large false aneurysm arising from the left coronary artery reattachment developed in 1 of them, and in the other, a patient with Marfan syndrome, there was complete dehiscence of both coronary artery anastomotic sites and additional aneurysmal involvement of the remaining distal ascending and transverse aortic arch. Five patients had had previous place- aortic dissection was present in 5 of them; acute dissection, in 1; and Marfan syndrome, in 10. Associated concomitant procedures were required in 45 patients (50%). These procedures included aortic arch replacement (with or without coronary artery bypass grafting) in 25, coronary artery bypass grafting in 14 (Fig 2), and a variety of other procedures in an additional 6 patients (Table 1). Among the 26 patients undergoing primary operation and a concomitant procedure, chronic dissection was present in 6 and acute dissection in 3. Twenty-three patients (26%) were undergoing a repeat operation, with or without a concomitant procedure, at the time of aortic root replacement; they had previously undergone one or more cardiac or proximal aortic operations. Among patients having a repeat operation, 13 had Table I. Concomitant Procedures - No. of Procedure Patients Survival Arch replacement with or without (92) coronary artery bypass grafting Coronary artery bypass grafting (86) Mitral valve replacement 3 2 (67) Aorta-right ventricular fistular repair 1 l(lo0) Atrial septa1 defect repair 1 l(lo0) Aorta-bifemoral bypass 1 1 (100) Total (89) Numbers in parentheses are percentages

3 560 COSELLI AND CRAWFORD Ann Thorac Surg 1989;47:55%65 Table 2. Previous Cardiac and Aortic Root Operations Operations No. of Patients Survival" CABG 4 4 (100) AVR with or without CABG 6 6 (100) Aortoplasty, AVR, CABG 5 4 (80) Ascending aortic graft with or without 8 8 (100) CABG and AVR Total (96) a Numbers in parentheses are percentages. AVR = aortic valve replacement; grafting. CABG = coronary artery bypass ment of an ascending aortic graft, and an aortic aneurysm proximal or distal to the graft and aortic valve insufficiency developed in all 5 (Fig 3). Two of them also had Marfan syndrome. There were 5 patients who had previously undergone aortic valve replacement and 4 who had had coronary artery bypass grafting; an aneurysm developed later in all 9. Acrtoplasty, with or without aortic valve replacement, had previously been performed in 5 patients. Two additional patients with Marfan syndrome had had a previous cardiac operation, mitral valve replacement in 1 and ao-tic valve and separate ascending aortic graft replacement in the other. Sinus segment and distal aortic aneurysm:, developed in both patients. An additional 2 patients, both with Marfan syndrome, had undergone previous pcrtus excavatum repairs. Four patients had had two previous cardiac procedures, and l patient had had four procedures. Operative Technique Surgical treatment of all patients was based on modifications of the technique described by Cabrol and colleagues [5, 61 in which a composite valve graft is inserted and the coronary artery origins are reattached using a separate, smaller Dacron tube graft. Total cardiopulmonary bypass using bicaval cannulation and a femoral artery for pump return was employed whenever possible. In 2 patients, Fig 3. (A) Drawing and aortogram of patient with intraluminal ascending aortic graft previously placed for acute type I dissection. Aortic valve insufficiency, sinus segment, and distal ascending aortic aneurysm are present. (B) Drawing and aortograin of postoperative appearance after aortic root replacement and ascending aortic repair. (C) Drawing and aortograni affer staged replacement of aneurysm of the false lurneri of the descending thoracic aorta.

4 Ann Thorac Surg 1989; COSELLI AND CRAWFORD 561 Fig 4. Modification of the procedure of Cabrol and co-workers 151 using hypothermic circulatory arrest. (ax) Distal anastonzosis is perfornied without aortic clamp to replace maximum amount of ascending aorta. (d-f) After distal graft has been clamped and cardiopulmonary bypass resumed, a conrposite valve graft is inserted and the coronary artery origins are reattached to the aortic graft using a srnnller, separate tube graft. femoral vein-femoral artery partial cardiopulmonary bypass was used to produce deep hypothermia and allow circulatory arrest before the opening of the sternum in patients with large aneurysms who had undergone multiple previous operations. Hypothermic hyperkalemic dilute blood cardioplegia and topical hypothermia were used for myocardial preservation. In patients requiring replacement of the aortic arch, in patients with acute aortic dissection, and in patients in whom safe distal aortic clamping was not feasible for anatomical reasons, profound hypothermia and circulatory arrest were used. In selecting the appropriate level of hypothermia at which to initiate a safe period of circulatory arrest, we continuously monitor the electroencephalogram and achieve electrocerebral silence before arresting the circulation [7]. A general description of the technique follows (Figs 4, 5). Cardiopulmonary bypass is established, and the ascending aorta is clamped as distally as possible. Alternatively the graft used to replace the transverse aortic arch is clamped just proximal to the innominate artery, and attention is directed to the aortic root. With the ascending aorta opened with a T incision, the aortic valve and sinuses are exposed. The coronary artery origins are identified, and cardioplegia is infused into each at regular intervals. One end of a 10-mm woven Dacron tube graft, which has been coated with commercially available 5% albumin and autoclaved for three minutes at 270 F (133.28"C), is sutured end-to-end to the aortic wall surrounding the left main coronary artery using a continuous suture. Patency of this anastomosis can be confirmed and additional myocardial protection provided by administering more cardioplegic solution through this graft.

5 562 COSELLI AND CRAWFORD Ann Thorac Surg 1989;47:55&65 Fig 5. (A) Drawing and aortograni of patient with chronic type 1 aortic dissection with aortic valve insufficiency. (B) Drawing and aortogram made postoperatively (see Fig 4) shouiing satisfactory reconstruction. A B An appropriately sized St. Jude Medical composite valve graft is also saturated with 5% albumin and autoclaved to render the interstices of the graft impermeable to heparinized blood. The valve end of the graft is inserted into the aortic annulus using closely spaced pledgeted mattress sutures. The graft portion of the composite prosthesis is cut to the desired length and anastomosed end-to-end to the completely transected distal ascending aorta or to a previously placed distal graft. The smaller Dacron tube graft is passed to the right of the aortic graft, cut to an appropriate length allowing for a gentle craniad curve, and attached end-to-end to the aortic wall surrounding the origin of the right coronary artery. Repair is completed by creating 3 side-to-side anastomosis between the transversely placed coronary artery graft and the aortic portion, with the composite graft on the right anterior lateral surface of the latter, about 5 cm from the valve annulus. Air is removed from the grafts and heart in a careful routine manner. We have found all suture lines to be accessible for securing hemostasis and, therefore, do not routinely tightly wrap the grafts with the aortic wall to achieve a dry field; rather, the aortic graft is loosely covered with redundant aneurysm wall to interpose tissue between it and the sternum. Because we have not relied on the inclusion technique for hemostasis, we have

6 Ann Thorac Surg 1989;4755E-65 COSELLI AND CRAWFORD 563 Table 3. Results With Modification of the Cabrol Operation" in 90 Patients Procedure No. of Patients Survivalh Aortic root reconstruction (93) Aortic root with (85) associated procedures Repeat aortic root with or (96) without associated procedures Total (91) a This refers to the operation of Cabrol and associates (5, 61. in parentheses are percentages. Numbers not found it necessary to routinely create a fistula between the periprosthetic space and the right atrium. All patients are given oral Coumadin (crystalline warfarin sodium) for long-term anticoagulation. Additional modifications are required in patients undergoing concomitant procedures or reoperation. For example, in patients in whom acute dissection destroys the origin of the right but not the left coronary artery, a small Dacron tube graft as described is interposed between the aortic graft and left coronary artery ostia, and continuity of the right coronary artery is achieved using a saphenous vein graft placed further distally on the coronary artery and taking the proximal end directly off the Dacron aortic graft. Severe distal coronary artery occlusive disease is bypassed with saphenous vein and internal mammary artery grafts in a routine manner, again with proximal anastomoses of vein grafts taken directly off the Dacron aortic graft. In patients undergoing reoperation, functioning saphenous vein bypass grafts are reattached to the aortic portion of the composite graft using buttons of aortic wall surrounding the proximal aortic anastomosis. When mitral valve replacement is required concomitantly, it can be accomplished through the aortic valve annulus, thereby avoiding a separate atrial incision [8]. Results Early Results The overall early (30-day or hospital) survival was 91% (82190) (Table 3). Three early deaths occurred in patients undergoing primary operation and isolated composite valve-graft insertion. There were 4 early deaths among the 26 patients undergoing primary operation and concomitant operations; 2 of the 4 patients had coronary artery bypass grafting and 1 each, mitral valve replacement and arch replacement. The remaining early death was in a patient having a reoperation for chronic dissection. Five years previously, this patient had undergone graft replacement of the ascending aorta for acute aortic dissection and subsequently required aortic root and arch replacement. Four of the early deaths were due to congestive heart failure. All 4 patients had had New York Heart Association functional class 111 or IV symptoms preoperatively. One of them underwent heart transplantation 3 days after operation and died 17 days later. Three deaths were the result of cardiac arrhythmias, all in patients with a preoperative history of arrhythmias. One early death was due to rupture of a dissecting thoracic aortic aneurysm 20 days after operation and after hospital discharge, before planned second-stage repair. Autopsy information was available on 5 patients; in each, the composite valve graft was satisfactory with all suture lines intact and all grafts patent. Among the 31 patients with aortic dissection, there were 30 early survivors (97%). Among the 59 patients without dissection, there were 52 early survivors (88%). Perioperative bleeding problems were few; only 4 patients (4.4%) had to be returned to the operating room because of hemorrhage. In only 1 patient was it necessary to wrap the graft for hemostasis and create a fistula to decompress the perigraft space. Six patients were successfully operated on without transfusion of blood or blood products. Additional early postoperative complications included transient focal neurological deficits, none of which were permanent, in 4 patients. Intraaortic balloon pump support was necessary in 3 (3.4%) of the 88 operative survivors. Heart block necessitating a permanent pacemaker and tracheostomy for prolonged respiratory support occurred in 2 patients each. There were two cases of sepsis, which were treated with 6 weeks of intravenously administered antibiotics. Postoperative aortography was performed in 42 (51 %) of the surviving patients before hospital discharge or on return for a second-stage distal aortic operation. In all 42, the proximal and distal anastomoses were intact, all transverse Dacron coronary artery grafts were patent, and there were no pseudoaneurysms at any sites. Late Results Follow-up information was available on all survivors either by physical examination or by correspondence directly with the patient using a standardized questionnaire or with the referring physician. There were 4 late deaths. Two were due to renal failure, 1 was due to myocardial infarction, and 1 was sudden and of unknown causes. One patient requiring hemodialysis died of progressive renal failure 3 months after composite valve-graft replacement of the aortic valve and ascending aorta, as well as arch replacement and reattachment of four previously placed coronary artery bypass grafts. The second patient who died of renal failure did so 2 months after a second-stage operation involving graft replacement of the descending thoracic aorta. A 70-year-old man died of a myocardial infarction 6 months after composite valvegraft replacement and coronary artery bypass grafting to four distal coronary arteries with saphenous vein grafts. Late morbidity involved transient ischemic attacks in 3 patients, one episode in each of the patients, which resolved completely in all 3 in less than 24 hours. Hepatitis developed in 2 patients, both of whom recovered. One patient who had undergone composite valve-graft replacement of the aortic valve and ascending aorta for acute type I dissection and concomitant double coronary

7 564 COSELLl AND CRAWFORD Ann Thorac Suq; 1989;475584?i artery bypass grafting for occlusive coronary artery disease was later taken off Coumadin in preparation for a craniotomy for an intracerebral aneurysm. Once this patient with diffuse coronary artery occlusive disease was no longer on a regimen of anticoagulants, thrombosis of the small Dacron graft to the left main coronary artery developed, resulting in an anterior myocardial infarction. Protected by the distal saphenous vein grafts, the patient recovered. No patient to date has required reoperation for problems related to the aortic root reconstruction using the technique described. Subsequent operations have included descending thoracic aortic aneurysm repair in 5 patients (1 death), thoracoabdominal aortic aneurysm repair in 1, muscle flap closure of the sternum in 1 patient who originally was seen with a sternal infection, abdominal aortic aneurysm repair in 1, carotid endarterectomy in 1, lymph fistula repair in 2, appendectomy in 1, and successful craniotomy for tumor in 1. Comment Composite valve-graft replacement of the aortic valve and ascending aorta has become a generally accepted surgical technique for treatment of aneurysmal involvement of the sinus segment with aortic valve insufficiency. Other indications include dissection and select cases of infection and reoperation. The most commonly employed procedure, originally described by Bentall and DeBono [l] in 1968, involves direct reattachment of the coronary artery origins to openings in a composite graft inserted using an inclusion technique, followed by wrapping the diseased aortic wall around the graft to achieve hemostasis. This approach was a major contribution because it allowed complete aortic root replacement with a reduced incidence of major hemorrhage. Nevertheless, employment of this technique has been associated with its own inherent limitations and difficulties [ With the use of the Bentall technique, hemorrhage at the time of insertion is primarily related to problems associated with coronary artery reattachment [14]. When the inclusion technique is used for composite valve-graft placement, there are virtually always overlapping and inaccessible suture lines. In addition, in annuloaortic ectasia, the coronary origins are displaced both distally and laterally from their normal anatomical position, thus necessitating tension when they are reattached to the graft. Early bleeding was not a major problem in our experience with the modifications of the procedure introduced by Cabrol and co-workers [S, 61. Only 4 patients (4%) needed reoperation for bleeding, 6 required no blood transfusions at all, and only 1 required a perigraft wrap and left-to-right fistula for hemostasis. In a review of 100 patients, Cabrol and colleagues [15] reported a similar experience with only 4 patients requiring reoperation for bleeding. Their group routinely employs graft wrapping to control bleeding and a fistula between the aortic wrap and the right atrial appendage to decompress the perigraft space. We attribute improved hemostasis to better exposure during suture placement, accessible suture lines, and elimination of tension on the coronary anastomosis with! the use of the interposed Dacron graft. Pseudoaneurysm formation after direct reattachment of the coronary arteries to a composite graft has been well documented [ This complication has been attrib-. uted to suture line tension due to anatomical factors related to the aortic root pathological condition being, treated, or to the accumulation of blood under pressure within the aneurysm wrap of the graft creating tension on the coronary ostial reattachment suture lines. Development of perigraft hematoma can also lead to supravalvular graft stenosis with immediate hemodynamic consequences. Kouchoukos and associates [16] studied by arteriography before hospital rlischarge 17 patients in whom the inclusion technique had been used, and found pseudoaneurysm formation at the coronary ostial anastomosis in 4. Stenosis of the left coronary ostium was noted in an additional patient. In late follow-up, they were able to identify 3 patients with pseudoaneurysm formation on aortograms made from 1 month to 69 months after hospital discharge. One patient underwent successful reoperation before hospital discharge, and 7 others were operated on from 3 to 69 months postoperatively (mean, 41 months), with 4 survivors. Others (9, 10, 12, 1.31 have reported similar experiences with pseudoaneurysm formation in 7% to 25% of patients. Cabrol and colleagues [15] reported on 2.5 patients who were reinvestigated by cardiac catheterization and angiography between 1 month and 5 years after operation to determine the long-term results of their approach. In all patients, they found a satisfactory appearance of the prosthesis, no pseudoaneurysm formation, and no stenosis at the junction of the coronary tube and the coronary ostia. We investigated by root aortography 42 (51%) patients surviving oprration, 41 before hospital discharge and 1 at 5 months postoperatively. In this larger group of patients studied in the early postoperative period, there were no pseudoaneurysms, tube graft occlusions, or coronary stenoses. The inadequacies 01' the conventional approach to aortic root replacement are most obvious in circumstances not allowing for ease of coronary ostial graft reattachment. In many reoperations, friable, immobile aortic tissue surrounding the coronary artery origins can present almost insurmountable techr ical difficulties when direct reattachment is attempted. Another obstacle is encountered when there has been failure of the coronary artery ostia to migrate a distance from the aortic valve annulus that is compatible with ease of reattachment [17, 181. This occurs when the aortic wall in the coronary sinus between the ostia and annulus is not involved in the expansion of the aneurysm. Both circumstances can produce troublesome intraoperative bleeding and late pseudoaneurysm formation. Use of a separate, smaller Dacron tube for coronary artery reattachment is applicable in both of these situations, ie, when the ostia and valve annulus are normally related and in a reoperation where there is limited tissue mobility. This is evidenced by 23 (26%) of our patients undergoing a reoperation without an increase in mortality or morbidity related to the technique (see Table 3).

8 COSELLI AND CRAWFORD 565 Aortic root replacement using a composite valve graft and a separate, smaller Dacron tube to bridge the aortic graft and coronary ostia is simple and safe, and can be accomplished with excellent operative mortality and morbidity in a wide variety of aortic pathologies. Importantly, compared with classic techniques, operative hemorrhage is greatly reduced, and early development of pseudoaneurysm formation at the coronary artery reattachment site is virtually eliminated. References Bentall H, DeBono A. A technique for complete replacement of the ascending aorta. Thorax 1968;23:33&9. Edwards WS, Kerr AR. A safer technique for replacement of the entire ascending aorta and aortic valve. J Thorac Cardiovasc Surg 1970;59: Miller DC, Stinson EB, Oyer PE, et al. Concomitant resection of ascending aortic aneurysm and replacement of the aortic valve. Operative and long-term results with conventional techniques in ninety patients. J Thorac Cardiovasc Surg 1980; 79: Moreno-Cabral RJ, Miller DC, Mitchell RS, et al. Degenerative and atherosclerotic aneurysms of the thoracic aorta. Determinants of early and late surgical outcome. J Thorac Cardiovasc Surg 1984;88:102CL32. Cabrol C, Gandjbakhch I, Cham B. Anevrismes de I'aorte ascendante. Replacement total avec reimplantation des artpres coronaires. Nouv Presse Med 1978;7:36>5. Cabrol C, Pavie A, Gandjbakhch I, et al. Complete replacement of the ascending aorta with reimplantation of coronary arteries. New surgical approach. J Thorac Cardiovasc Surg 1981;81: Coselli JS, Crawford ES, Beall AC Jr, Mizrahi EM, Hess KR, Patel VM. Determination of brain temperatures for safe circulatory arrest during cardiovascular operation. Ann Thorac Surg 1988;45: Crawford ES, Coselli JS. Marfan's syndrome: combined composite valve graft replacement of the aortic root and transaortic mitral valve replacement. Ann Thorac Surg 1988;45: McCready RA, Pluth JR. Surgical treatment of ascending aortic aneurysms associated with aortic valve insufficiency. Ann Thorac Surg 1979;28: Mayer JE Jr, Lindsay WG, Wang Y, Jorgensen CR, Nicoloff DM. Composite replacement of the aortic valve and ascending aorta. J Thorac Cardiovasc Surg 1978;76: Kouchoukos NT, Karp RB, Blackstone EH, Kirklin JW, Pacifico AD, Zorn GL. Replacement of the ascending aorta and aortic valve with a composite graft. Ann Surg 1980;192: Donaldson RM, Ross DN. Composite graft replacement for the treatment of aneurysms of the ascending aorta associated with aortic valvular disease. Circulation 1982;66: Marvasti MA, Parker FB, Randall PA, Witter GA. Composite graft replacement of the ascending aorta and aortic valve. Late follow-up with intra-arterial digital subtraction angiography. J Thorac Cardiovasc Surg 1988;95:92p Symbas PN, Raizner AE, Tyras DH, Hatcher CR Jr, Ingelesby TV, Baldwin DJ. Aneurysms of all sinuses of Valsalva in patients with Marfan's syndrome. Ann Surg 1971;174: Cabrol C, Pavie A, Mesnildrey P, et al. Long term results with total replacement of the ascending aorta and reimplantation of the coronary arteries. J Thorac Cardiovasc Surg 1986;91: Kouchoukos NT, Marshall WG Jr, Wedige-Stecher TA. Eleven year experience with composite graft replacement of the ascending aorta and aortic valve. J Thorac Cardiovasc Surg 1986;92: Piehler JM, Pluth JR. Replacement of the ascending aorta and aortic valve with a composite graft in patients with nondisplaced coronary ostia. Ann Thorac Surg 1982;33: Grey DP, Ott DA, Cooley DA. Surgical treatment of the ascending aorta with aortic insufficiency. A selective approach. J Thorac Cardiovasc Surg 1983;86: