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Replacement of the Ascending Aorta and Aortic Valvewith a Composite Graft
Results in 86 Patients
NICHOLAS T. KOUCHOUKOS, M.D., ROBERT B. KARP, M.D., EUGENE H. BLACKSTONE, M.D., JOHN W. KIRKLIN, M.D.,ALBERT D. PACIFICO, M.D., GEORGE L. ZORN, M.D.
We reviewed our entire experience with composite graftreplacement of the ascending aorta and aortic valve duringa 63 month interval ending in December, 1979. Anuloaorticectasia was the most common indication for operation, fol-lowed by aortic dissection (acute and chronic). Hospital mor-tality was 5% and was related to the preoperative functionalstatus and the duration of intraoperative myocardial ischemia.Reoperation on the ascending aorta for reasons other thanpostoperative hemorrhage was required in five of the 82 hospitalsurvivors (6%). By actuarial analysis, 90% of hospital sur-vivors were free of any reoperation on the ascending aortaor aortic valve three years postoperatively, and 93% were freeof reoperation related specifically to the composite graft.Pseudoaneurysms at the coronary ostia or distal aortic anasto-mosis were observed in five of 16 patients having postoperativeangiography. One of the five patients has required reoperation.Follow-up has averaged 23.5 months (range: 0.2-60 months).Three year actuarial survival for the 86 patients was 81%,for 44 patients with anuloaortic ectasia was 88%, and for 31patients with aortic dissection was 83%. Composite graftreplacement of the ascending aorta and aortic valve is a satis-factory alternative to supracoronary graft replacement andaortic valve replacement. It offers the advantage of excludingall aneurysmal tissue from the aortic anulus to the innominateartery, thereby eliminating the potential for later develop-ment of aneurysms of the sinuses of Valsalva, a known com-plication of the supracoronary technique. It is the method ofchoice for patients with anuloaortic ectasia and cephaladdisplacement of the coronary ostia. It is suitable for manypatients with acute or chronic dissection and for patientswith sinuses of Valsalva aneurysms following previous opera-tions on the ascending aorta or aortic valve.
U NCERTAINTY EXISTS REGARDING the optimalsurgical treatment of aneurysms of the ascending
aorta associated with aortic valvular disease. Twogeneral methods are currently employed: 1) Supra-coronary graft replacement of the ascending aorta and
Presented at the Annual Meeting of the American SurgicalAssociation, Atlanta, Georgia, April 23-25, 1980.
Reprint requests: Nicholas T. Kouchoukos, M.D., Departmentof Surgery, UAB, University Station, Birmingham, Alabama 35294.
From the Division of Cardiovascular and ThoracicSurgery, Department of Surgery, School of Medicine,
University of Alabama, Birmingham, Alabama
aortic valve replacement (or repair), and 2) replacementof the ascending aorta and aortic valve with a com-posite graft consisting of a woven Dacrong tube graftand an aortic valve prosthesis, with anastomosis of thecoronary arteries to the tube graft.
In this report we present our total experience withcomposite graft replacement of the ascending aorta andaortic valve during a five-year period. Based on thisexperience, our current indications for the use of thisprosthesis are presented.
Materials and Methods
Between September, 1974, and December, 1979, 86patients had replacement of the ascending aorta andaortic valve with a composite graft. The results ofoperation in the first 25 of these patients have beenpreviously reported.' The mean age of the 86 patientswas 48 years (range: 16-77 years), and 59 patients(69o) were males. Nineteen of the patients (22%) hadclinical stigmata of Marfan's syndrome. The abnor-malities of the ascending aorta resulting in the aneurysmalchanges are summarized in Table 1. Anuloaortic ectasia2(dilatation of the sinuses of Valsalva with associatedmoderate or severe aortic valvular incompetence,cephalad displacement of the coronary ostia, andvarying degrees of dilatation of the more distal ascend-ing aorta) was the most common indication for opera-tion. Six of the 21 patients with DeBakey Type I andseven of the ten patients with DeBakey Type II dis-sections3 also had anuloaortic estasia. Nine of the86 patients (10%o) had previous operations on the ascend-ing aorta and/or aortic valve a mean of64 months (range:30-95 months) prior to operation. Seven of these
0003-4932/80/0900/0403 $01.05 © J. B. Lippincott Company
403
KOUCHOUKOS AND OTHERS
TABLE 1. Abnormalities of the Ascending Aorta in the 86 Patients
NumberAbnormality of Patients
Anuloaortic ectasia 44
DeBakey Type I dissection 21acute 7chronic 14
DeBakey Type II dissection 10acute 1chronic 9
Aneurysms of sinuses of Valsalva following graftreplacement of ascending aorta for: 8
dissection 7anuloaortic ectasia 1
Poststenotic dilatation 1
Luetic aortitis 2
Total 86
patients had graft replacement of the ascending aortafor acute or chronic dissection and developed progres-sive aortic valvular incompetence and aneurysms ofthe sinuses of Valsalva. One patient had anuloaorticectasia and had undergone supracoronary graft replace-ment and insertion of an aortic valve allograft. At thesecond procedure, the degenerated allograft and theaneurysmal sinuses of Valsalva were replaced with a
composite graft. The ninth patient had stenosis of a
Starr- Edwards cloth-covered metallic ball prosthesis(Model 2320) and severe poststenotic dilatation of theascending aorta.The preoperative New York Heart Association
functional class for 85 patients is shown in Table 2(class unknown for one patient). Nine patients wereClass I, 25 were Class II, 35 were Class III, and 16patients were Class IV. Of the 16 Class IV patients,five required emergency operation for acute dissection.We have termed these patients Class V for purposesof analysis.During the study interval, 11 additional patients had
supracoronary graft replacement of the ascendingaorta and aortic valve replacement. Two patientshad anuloaortic ectasia, four had acute dissections,one had poststenotic dilatation of the ascending aorta,and four had aneurysms of the ascending aorta whichdid not involve the sinuses of Valsalva with associatedaortic valvular incompetence. Use of a compositegraft was deemed unnecessary by the surgeon or couldnot be used for technical reasons in eight of thesepatients. There were two hospital deaths. These patientswill not be considered in the subsequent analyses.
Operative TechniqueThe most commonly employed technique, with
modifications, was that described by Bentall and De
Bono4 and Edwards and Kerr,5 and was used in 75patients (Group I). A median sternotomy incision isused and the common femoral artery is exposed forcannulation. A large single venous cannula is insertedinto the right atrium for venous return into the extra-corporeal circuit. Cardiopulmonary bypass is establishedat a flow of 2.2 LImin/M2 using hemodilution (hematocrit20-30%) and moderate systemic hypothermia (24-28 C). Lower temperatures and flows are often usedfor short intervals. Direct coronary perfusion wasused as the method for myocardial protection in fivepatients. In 32 patients, internal and external coolingof the myocardium with 4 C Ringer's solution duringaortic clamping was used.1 In the 49 remaining and mostrecent patients, hypothermic potassium-inducedcardioplegia was employed using a standard solution6infused into the coronary ostia. With the cardioplegictechnique, myocardial temperature is measured con-tinuously during the period of aortic clamping using athermistor probe, and is kept below 18 C by additionalinfusions of the cardioplegic solution.A vent is inserted into the left ventricle through the
right superior pulmonary vein. After clamping the aortajust below the innominate artery, the ascending aortais opened anteriorly using a vertical incision which isextended obliquely toward, but not into, the non-coronary sinus (Fig. la). None of the aneurysm isexcised and the edges are retracted with stay sutures(Fig. lb). The aortic leaflets are excised and the ap-propriate-sized composite prosthesis is selected. Theprosthesis is usually preclotted by adding topicalthrombin (2 ampules) to 50 ml of warm heparinizedblood collected at the beginning of cardiopulmonarybypass. While the graft is being prepared, double-armed 2-0 Ticrong pledgeted sutures are placed intothe aortic anulus. These are then passed through thesewing ring of the prosthesis (Fig. Ic) and secured.They are placed close enough to each other to assurea watertight closure (Fig. ld). Single interrupted
TABLE 2. Preoperative Functional Class
NYHA* Functional ClassNo. of
Aortic Disease Patients I II III IV "V"t
Anuloaortic ectasia 44t 4 14 19 7Chronic dissection 30 5 11 13 1Acute dissection 8 1 2 5Luetic aortitis or
poststenotic di-latation 3 2 1
Totals 85 9 25 35 11 5
* New York Heart Association.t Emergency operation.t Class unknown for one patient.
404 Ann. Surg. o September 1980
Vol. 192 o No. 3
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Ann. Surg. * September 1980KOUCHOUKOS AND OTHERS
sutures or a continuous Proleneg suture techniquecan also be used. A button of graft, 8-10 mm in di-ameter, is next excised from the graft with a cautery*in the area corresponding to the location of the leftcoronary ostium (Fig. Id). The graft is sutured to theaortic wall adjacent to the ostium with a continuous4-0 Prolene suture. (Figs. Id and e). If the aortic wall isfriable, the suture line can be reinforced with pledgetedmattress sutures as described by Mayer et al.7 A buttonof graft is similarly excised anteriorly and the graftis sutured to the right coronary ostium (Fig. le). Theleft edge of the divided aorta is reflected anteriorlyas this anastomosis is completed (Fig. If). In cases ofacute or chronic dissection, the aortic tissue around thecoronary ostia, particularly the right, may be friable.In this situation or in others which the aortic tissuemay not support sutures, it is preferable to detach thecoronary ostium and suture it directly to the tube graftor perform an end-to-end8'9 or end-to-side anastomosisto a saphenous vein graft, anastomosing the proximalend of the vein graft to the tube graft or to the aortadistal to the graft.The tube graft is then trimmed to the appropriate
length and is bevelled with the tip of the bevel anteriorly.A strip of Teflon® felt is passed around the aorta and isused to reinforce the distal suture line (Fig. If). Thegraft is anastomosed to the aorta just proximal to theaortic clamp with a 3-0 Prolene suture using a horizontalmattress stitch which begins posteriorly and incor-porates the Teflon strip, the aorta (both inner andouter layers when a dissection is present) and the graft.The suture line is extended anteriorly everting the graftunder the opened aorta, and secured (Figs. lg and h).Rewarming is begun, a needle vent is placed in theaorta distal to the graft, and the aortic clamp is openedto evacuate air from the graft and to locate areas onthe various suture lines that may require reinforcingsutures. Usually, there is minimal bleeding throughthe graft. The edges of the aorta are trimmed (Fig. lh),and approximated with a continuous 3-0 Prolene suturereinforced with strips ofTeflon felt (Fig. li). If bleedingthrough the graft is excessive, the aorta is reclampedand the closure completed. After closure of the aorta,the heart is defibrillated, the left-sided vent is removed,air is evacuated from the left ventricle and aorta, andcardiopulmonary bypass is discontinued.
In patients with previous graft replacement of theascending aorta who develop aneurysms of the sinusesof Valsalva, the dilated noncoronary sinus is incisedand the operation is performed similarly except that thetube graft is sutured distally to the previously insertedDacron graft.An alternative technique. was employed in 11 of the
* Concept Cautery, Concept, Inc., Clearwater, Florida.
86 patients (Group II). Four of these had anuloaorticectasia, four had acute or chronic dissections, andthree had aneurysms of the sinuses of Valsalva follow-ing previous operations for acute dissection. Theascending aortic aneurysm is totally or partially excised,the aortic valve is excised, and the aortic prosthesisis sutured to the anulus. Buttons of aorta surroundingthe coronary ostia are fashioned and are anastomosedto openings in the tube graft. The procedure is other-wise similar to that for the Group I patients exceptthat the aorta is not wrapped around the graft. Technicalproblems precluded wrapping in six of these patients.The surgeon elected not to wrap the aorta in the otherfive patients.A total of ten patients (eight patients in Group I, two
patients in Group II) required coronary bypass grafts(eight for coronary atherosclerosis and two becauseof difficulty in completing the graft-coronary ostialanastomoses). The anastomoses of the grafts to thecoronary arteries were performed during the period ofaortic clamping. The anastomoses to the aorta distal tothe aortic graft or to the graft were performed aftercompletion of the distal aortic anastomosis. Two pa-tients required concomitant mitral valve replacement.The mean duration (+SD) of cardiopulmonary bypasswas 116 ± 36.8 minutes (range: 73-317 minutes) and ofaortic clamping 79 ± 19.4 minutes (range: 50-134minutes). The duration of hypothermic ischemic arrestfor 32 patients was 69 ± 14.7 minutes and of hypo-thermic cardioplegia for 49 patients was 85 ± 20.1minutes.
In 25 patients, woven Dacron tube grafts were suturedto various prosthetic valves: Starr-Edwards Model1260 aortic prostheses (four patients), porcine xeno-grafts (four patients), or Biork-Shiley tilting-discprostheses (17 patients). The tube grafts were 3-5 mmlarger in diameter than the outside diameter of the pros-thetic sewing ring. Composite grafts prepared by theShiley Laboratories (Biork-Shiley Aortic Graft ValveProsthesis) were used in the remaining 61 patients.
Follow-up
Follow-up information was available for all hospitalsurvivors. Evaluation was by examination or by cor-respondence with the patient and the referring physician.The date of last inquiry was between November 1979and January, 1980. The mean duration of follow-upwas 23.5 months (range 0.2 to 60 months). Thirty-eight patients have been followed for more than twoyears and 22 for more than three years.
Statistical Methods
Characteristics of the study group were analyzedusing the standard t-test (with correction for non-
406
REPLACEMENT OF THE AORTIC ROOT
TABLE 3. Hospital Mortality
Hospital Deaths 70%oNo. of Confidence pPatients No. Per Cent Limits Value
Aortic diseaseanuloaortic ectasia 45 0 0-4%chronic dissection 30 1 3 0.4-11% 0.01acute dissection 8 2 25 8-50%luetic aortitis or poststenotic dilatation 3 1 33 4-76%
Myocardial protectioncoronary perfusion 5 0 0-31% 1hypothermic ischemic arrest 32 2 6 2-14% 0.7hypothermic cardioplegia 49 2 4 1-9%
Operative techniquegroup I 75 2 3 1-6% 0.08group II 11 2 18 6-38%0
homogeneous variances when the F-test rejected atp < 0.2) and the nonparametric rank test for con-
tinuous variables, and contingency table analysisfor categorical variables (Fisher's exact test was usedfor 2 x 2 tables and the maximum likelihood chi square
test for 2 x K tables).Factors associated with incremental risk of hospital
death were identified using multivariate logistic regres-
sion analysis.10 The variables examined included age
at operation, the extended preoperative New YorkHeart Association functional class, myocardial ischemictime, the use of coronary bypass grafting, Group Iversus Group II, and aortic pathology.
Actuarial analyses were performed using the product-limit method.'1 Factors associated with sudden latedeath were analyzed using multivariate proportionalhazard regression.'2"13
Results
Early Results
Mortality. Hospital mortality was 5% (four patients).There were no deaths among the 45 patients withannuloaortic ectasia, one death in the 30 patients withchronic dissection (3%), two deaths in eight patientswith acute dissection (25%), and one death among thethree patients with luetic aortitis or poststenoticdilatation (33%) (Table 3). There were no deaths amongthe nine patients undergoing secondary procedures,and they are included in the above categories in Table3. Hospital mortality was not affected by the type ofintraoperative myocardial protection employed.Mortality was 3% (2/75) for the Group I patientsand 18% (2/11) for the Group II patients (p = 0.08)(Table 3).Three of the deaths resulted from myocardial failure
and one from hemorrhage. All occurred intraopera-tively. None ofthe three patients with myocardial failurehad cardiogenic shock preoperatively. Two of the
four deaths occurred in the eight patients with acutedissection and both were in Group II. Multivariateanalysis identified two factors associated with increasedrisk of operation: the preoperative augmented func-tional class and the duration of myocardial ischemia.Hypothermic ischemic arrest imposed an additionalrisk when compared to hypothermic cardioplegia(Table 4). Age of the patient, the type of operation,coronary bypass grafting, and aortic pathology werenot found to be incremental risk factors, though thenumber of events for such an analysis was small.
Morbidity. Reoperation for hemorrhage was requiredin 11 (13%) of the 82 hospital survivors (9/73 GroupI and 2/9 Group II, p = 0.3). In the Group I patientsthe bleeding originated from the suture line in theaorta over the graft in one patient, from a saphenousvein graft in one patient, and from the mediastinaltissues in the remaining seven patients. In both of theGroup II patients the bleeding originated from thesuture lines.One patient required reoperation early postopera-
tively for prosthetic valvular incompetence. Thisresulted from compression of the tube graft immediatelyabove the valve by the aortic wall which had beenclosed tightly over the proximal portion of the graft.This compression impeded the function of a Bjork-
TABLE 4. Multivariate Logistic Regression Analysisof Hospital Deaths
LogisticCoefficient
Variable ± SD* p Value
Augmented NYHA functionclass 3.0 ± 1.49 0.05
Myocardial ischemic time (min) 0.09 ± 0.040 0.03Additional effect of myocardial
ischemic time in ischemicarrest group 0.04 ± 0.020 0.07
* Intercept: -23 + 9.9 (p = 0.02).
Vol. 192 . NO. 3 407
KOUCHOUKOS AND OTHERS
1(33)
(11) (8)FIG. 2. Actuarial survivalof the 86 patients. Thebracketed vertical linesenclose the 70o confidencelimits (1 standard deviation).Numbers in parenthesesare the patients alive at theend of that interval. Nodeaths occurred after 40months and the survivalline is dashed to the time oflast followup.
0 6 1 2 18 24 30 36 42 48
MONTHS AFTER OPERATION
Shiley disc valve. At reoperation, a Dacron patch was
sutured to the aortic wall to enlarge this area and thepatient recovered uneventfully. None of the 73 Group Ipatients surviving operation required reoperation forcompression of the graft resulting from hematomabetween the graft at the aortic wall.
Thirteen patients (16%) received inotropic supportfor more than six hours postoperatively. The per-centages were similar for the three types of myocardialprotection. Two of the 82 operative survivors receivedintra-aortic balloon pumping. Twenty-five patients(30%) required treatment of ventricular arrhythmiasin the postoperative period. Six of these patientsdeveloped ventricular tachycardia and one had ven-
tricular fibrillation. No patient developed permanentheart block, pulmonary insufficiency requiring pro-
longed endotracheal intubation or tracheostomy, or
renal insufficiency. Three patients had focal neuro-
logic deficits which resolved.Postoperative aortic root angiograms were per-
formed in 16 patients (15 Group I, 1 Group II). Pseudo-aneurysms were noted at one of the coronary ostia infour and at the distal anastomosis in one ofthe 15 GroupI patients. One pseudoaneurysm occurred among 6patients with anuloaortic ectasia and four among ninepatients with aortic dissection. Early reoperationwas not performed in any of these five patients. Oneunderwent late reoperation. All are alive and withoutsymptoms. The angiographic study of the single GroupII patient was unremarkable. Stenosis of the left maincoronary ostium was noted in one Group I patient. At
the initial operation, the coronary ostia were not dis-placed far cephalad and the sinuses of Valsalva proximalto a large aneurysm of the ascending aorta were onlyminimally enlarged. A saphenous vein graft was insertedinto the anterior descending coronary artery at a sub-sequent procedure.
Late Results
Mortality. There have been ten late deaths. Fivepatients died suddenly, presumably of arrhythmias.Four of these had been treated for ventricular ar-
rhythmias early postoperatively, and one requiredinsertion of a pacemaker for control of arrhythmiasfollowing a previous operation (aortic valve replace-ment). One died following cardioversion for atrialfibrillation. Autopsy of this patient showed an en-
larged heart with biventricular hypertrophy (650 g).The composite conduit was functioning properly andboth coronary ostia were widely patent. One of theremaining three patients dying suddenly had post-operative angiography demonstrating a normally func-tioning graft. One patient each died of prosthetic endo-carditis following reoperation, of congestive failure,of a cerebrovascular accident, of intracranial hemor-rhage and following blunt trauma.
Multivariate analysis of sudden death yielded onlyone significant variable (p < 0.2): treated ventriculararrhythmias early postoperatively (hazard coefficient2.2 + 1.12, p = 0.05; representing a 9.4 times increasedhazard over patients not experiencing such rhythmdisturbances).
408100
90
80
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2 60
450
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Ann. Surg. * September 1980
REPLACEMENT OF THE AORTIC ROOT
100
90
80
FIG. 3. Actuarial survivalof 44 patients with primaryoperations for anuloaorticectasia.
I-
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wa.
70
60
50
40
30
20
10
0
5) (2)
0 6 12 18 24 30 36 42 48
MONTHS AFTER OPERATION
Actuarial survival of the 86 patients is shown in Fig.2. The survival rate was 87% at two years and 81% atthree years. No deaths have occurred among the 11patients followed longer than 40 months. Survival ofthe 44 patients with primary operations for anulo-aortic ectasia is shown in Figure 3. Two and threeyear survival rates were 92 and 88% respectively.
Survival of the 31 patients with primary operationsfor acute or chronic dissection are shown in Figure 4.The two and three year survival rates were 83%.Reoperations. A total of five of the 82 hospital sur-
vivors (6%) underwent reoperations on the ascendingaorta for reasons other than postoperative hemor-rhage: two for prosthetic endocarditis, one and five
100
904
80
FIG. 4. Actuarial survivalof 31 patients with primaryoperations for acute orchronic dissection.
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5
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40
30
20
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MONTHS24
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OPERATION
36 42 48
Vol. 1929No. 3 409
:1
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KOUCHOUKOS AND OTHERS
(79) (66)I (20)- -
(8)
((20 (8)
* ALL REOPERATIONS
O EXCLUDING PATIENTSWITH PROSTHETICENDOCARDITIS
FIG. 5. Actuarial prob-ability of freedom from re-operation on the ascendingaorta or aortic valve follow-ing composite graft replace-ment.
0 6 12 18 24 30 36 42 48
MONTHS AFTER OPERATION
months postoperatively, one for acute compressionof the graft by the aorta (see above), one for bypassgrafting of a stenotic left main coronary artery threemonths postoperatively (see above), and one for repairof a pseudoaneurysm of a coronary ostial-graftanastomosis 36 months postoperatively. Of these fivepatients, all but one with endocarditis survived re-
operation. The percentage of surviving patients free ofreoperation and the percentage of patients free of re-
operation related specifically to the composite graft(two patients with prosthetic endocarditis excluded)are shown in Figure 5. At three years, 90% of thepatients were free ofany reoperation and 93% were freeof reoperation related to the composite graft. No re-
operations have been required among the last 51 pa-
tients. Four patients required operation for aneurysmsof the descending thoracic or abdominal aorta 10-49months postoperatively. All survived operation.Thromboembolism. All but the four patients re-
ceiving porcine heterografts received long-term antio-coagulation with warfarin. Seven of the 82 hospitalsurvivors sustained probable cerebral emboli. Five ofthese resulted in permanent neurologic deficits, andone was fatal. One patient had a cerebral hemorrhagebut is alive and free of neurologic deficit and remainson warfarin. The actuarial percentage of patients freeof thromboembolism was 90% at two years and 85%at three years.Symptomatic status of hospital survivors. At last
follow-up of the 82 hospital survivors, ten were dead,
39 (48%) were Class I, 22 survivors (27%) were ClassII, three (4%) were Class III, one survivor (1%) was
Class IV, and in seven survivors the status was
unknown.
DiscussionIn September 1974, we began an evaluation of the
composite graft technique for replacement of theascending aorta and aortic valve and reported our
experience with the first 25 patients in 1977.1 Since theinitial operation, the technique has been used in 86 of97 patients requiring operation on the ascending aortaand aortic valve. The composite technique offeredthe potential advantage of excluding all abnormalaorta from the aortic anulus to the innominate artery,thus eliminating subsequent aneurysm formation of thesinuses of Valsalva, a complication that has been ob-served with the conventional supracoronary techniquein patients with cystic medial degenerative changes ofthe aorta.14'15 Another potential advantage appeared tobe the elimination of bleeding through the graft andsuture lines when the aorta was wrapped around thegraft before discontinuation of cardiopulmonary by-pass. Paraprosthetic leakage, a complication of theconventional technique16'17 should also be eliminatedwith a composite graft.Our results indicate that composite grafting can be
performed with a hospital mortality rate similar tothat reported in recent years with the conventionaltechnique.'5'17-'9 Mortality in our series was related im-
I410
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Ann. Surg. * September 1980
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Vol. 192 * No. 3 REPLACEMENT OF T
portantly to preoperative functional class and to pro-
longed intraoperative myocardial ischemia, particularlywhen hypothermic ischemic arrest was employed. Nodeath from hemorrhage occurred in the Group I pa-
tients and one death in the Group II patients (overallincidence 1.2%). This incidence is comparable to thatfor the conventional technique which has ranged from 0to 3.3%.15,17-19
Reoperation for hemorrhage was required in 13%of our operative survivors. In only one of the 9 Group Ipatients was the bleeding related to one of the suturelines, whereas this was the source for bleeding in bothGroup II patients. Thus, although wrapping ofthe aortaaround the graft has resulted in a low incidence ofbleeding from suture lines, hemorrhage requiringreoperation has not been eliminated by this maneuver.
The overall incidence of reoperation for hemorrhagealso does not differ from that for the conventionaltechnique. 15,17-19
Reoperations for complications related to the com-
posite prosthesis were required in five patients (6%,70% confidence limits (CL) 3% to 10%). By actuarialanalysis, 93% of hospital survivors were free of re-
operations related specifically to the composite graftthree years postoperatively. Liddicoat et al.18 reportedreoperation on the aortic valve in one of 87 patients(1%, CL 0-4%) surviving operation for replacementof the ascending aorta with or without aortic valvereplacement. McCready and Pluth'5 reported reopera-
tions on the ascending aorta or aortic valve in 10 of 54patients (18.5%, CL 13-26%) with the conventionaltechnique who were followed a mean of 72 months.Recently, Miller et al.17 reported three late reopera-tions for problems related to the aortic prosthesisor aortic root in 78 hospital survivors (4%, CL 2-8%)using the conventional technique. Their actuarialanalysis of late reoperation included patients withoperations on the thoracic and abdominal aorta as welland comparison with our data is not possible.
Although pseudoaneurysms at the coronary ostia anddistal aortic suture line were observed in five of our
16 patients having postoperative angiography, we didnot perform routine reoperation to correct these ab-normalities. Only one patient required reoperation36 months postoperatively because of recent onset ofchest pain which was felt to be related to the pseudo-aneurysm. No evidence for enlargement of the aortaon the chest roentgenogram was present. The otherfour patients are free of symptoms. Four of the fivepseudoaneurysms occurred among patients with acuteor chronic dissection and three of these occurred atthe coronary ostia. With increasing experience, we
would now employ saphenous vein grafts if we were
uncertain about the integrity of the coronary ostial-graft anastomosis.
HE AORTIC ROOT 411
In comparing the composite with the conventionaltechnique, a major issue is the incidence of aneurysmformation of the sinsuses of Valsalva severe enoughto produce complications and require surgical cor-rection, when they are not excised or excluded at theprimary operation. McCready and Pluth noted thedevelopment of aneurysms of the sinuses of Valsalvarequiring reoperation in five of31 patients who survivedaortic valve replacement and supracoronary grafting.Cystic medial degenerative changes in the aorta werepresent in all five patients. This was a late complication,with reoperation being performed from 74 to 108 monthspostoperatively. In our series, eight patients developedaneurysms of the sinuses of Valsalva following previousgraft replacement of the ascending aorta for aorticdissection or anuloaortic ectasia by the conventionaltechnique, and required reoperation 30-95 monthspostoperatively. Other groups have also reported thislate complication.14'18 Miller et al.17 using the con-ventional technique but with excision of all the ascend-ing aorta except for tongues of aortic wall surroundingthe coronary ostia as described by Wheat,'6 reportedno recurrent aneurysms of the aortic root. However,the number of patients undergoing postoperativeangiography was not stated. Three of their patientsrequired reimplantation or grafting of the right or leftcoronary artery because of anuloaortic ectasia. Webelieve that the development of aneurysms of thesinuses of Valsalva will occur in patients with cysticmedial degenerative changes if the sinuses are notexcluded or excised at the initial operation, and thatthe composite graft technique will eliminate the oc-currence of this complication.We conclude that composite graft replacement of the
ascending aorta and aortic valve is a satisfactoryalternative to supracoronary graft replacement andaortic valve replacement. Hospital and late mortalityrates are comparable to or lower than those reportedwith the conventional technique. The incidence ofmajor postoperative and late prosthetic-related com-plications is similar with the two techniques.We believe composite graft replacement is the
method of choice for patients with anuloaortic ectasiawhen there is cephalad displacement of the coronaryostia. It appears suitable for many patients with acuteor chronic dissections of the ascending aorta, par-ticularly when there is coexisting anuloaortic ectasia.When the dissection involves a coronary ostium, directanastomosis of the ostium to the graft or to a saphenousvein, or vein bypass grafting should reduce the incidenceof coronary ostial-graft pseudoaneurysms. The tech-nique has also been satisfactory for repair of sinusof Valsalva aneurysms associated with aortic valveincompetence following graft replacement of theascending aorta for acute or chronic dissection.
412 KOUCHOUKOS AND OTHERS Ann. Surg. * September 1980
AcknowledgmentsThe technical assistance of Phyllis Newsom, Rob Brown, Stan
Mitchell and Ann Couch is gratefully acknowledged.
References1. Kouchoukos NT, Karp RB, Lell WA. Replacement of the
ascending aorta and aortic valve with a composite graft:results in 25 patients. Ann Thorac Surg 1977; 24:140-48.
2. Ellis PR, Cooley DA, DeBakey ME. Clinical considerations andsurgical treatment of annulo-aortic ectasia. J Thorac Cardio-vasc Surg 1961; 42:363.
3. DeBakey ME, Cooley DA, Creech O, Jr. Surgical considerationsof dissecting aneurysm of the aorta. Ann Surg 1955; 142:586.
4. Bentall HH, DeBono A. A technique for complete replace-ment of the ascending aorta. Thorax 1968; 23:338.
5. Edwards WS, Kerr AR. A safer technique for replacement ofthe entire ascending aorta and aortic valve. J Thorac Cardio-vasc Surg 1970; 59:837.
6. Conti VR, Bertranou EG, Blackstone EH, et al. Cold cardioplegiaversus hypothermia for myocardial protection. J ThoracCardiovasc Surg 1978; 76:577-89.
7. Mayer JE, Jr, Lindsay WG, Wang Y, et al. Composite replace-ment of the aortic valve and ascending aorta. J ThoracCardiovasc Surg 1978: 76:816-23.
8. Blanco G, Adam A, Carlo V. A controlled approach to annulo-aortic ectasia. Ann Surg 1976; 183:174.
9. Zubiate P, Kay JH. Surgical treatment of aneurysm of theascending aorta with aortic insufficiency and marked dis-
placement of the coronary ostia. J Thorac Cardiovasc Surg1976; 71:415.
10. Walker SH, Duncan DB. Estimation of the probability of anevent as a function of several independent variables. Bio-metrika 1967; 54:167-79.
11. Kaplan EL, Meier P. Nonparametric estimation from incom-plete observations. Am Stat Assoc J 1958; 53:457-81.
12. Cox DR. Regression models and life-tables. J R Stat Soc Britain1972: 34:187-20.
13. Breslow N. Covariance analysis of censored survival data. Bio-metrics 1974; 30:89-99.
14. Symbas PN, Raizner AE, Tyras DH, et al. Aneurysms of allsinuses of Valsalva in patients with Marfan's syndrome: anunusual late complication following replacement of aorticvalve and ascending aorta for aortic regurgitation and fusiformaneurysms of ascending aorta. Ann Surg 1971; 174:902.
15. McCready RA, Pluth JR. Surgical treatment of ascendingaortic aneurysms associated with aortic valve insufficiency.Ann Thorac Surg 1979; 28:207- 16.
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17. Miller DC, Stinson EB, Oyer PE, et al. Concomitant resectionof ascending aortic aneurysm and replacement of the aorticvalve. J Thorac Cardiovasc Surg 1980; 79:388-401.
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DISCUSSION
DR. JOHN A. WALDHAUSEN (Hershey, Pennsylvania): My col-leagues and I also have used this technique successfully. However,I would like to report about one patient in whom we inserted a com-posite graft. It was a young man with Marfan's disease. Dr. GrantParr, my associate, used a Shiley-supplied composite graft.The patient did well for about one year, when he suddenly had a
massive stroke and died. At autopsy, the entire pseudointima of thegraft had loosened. We believe this is a serious problem. It is relatedto the fact that the graft was low-porosity. We believe this is worse inthis situation, because this low-porosity graft is being wrapped withthe aorta, making it more difficult for ingrowth into the graft.Has Dr. Kouchoukos had any problems with this graft. Indeed,
what graft does he use? Is it low porosity or standard porosity?
DR. HASSAN NAJAFI (Chicago, Illinois); One aspect of the authors'presentation is somewhat in contrast with my experience at Pres-byterian-St. Luke's Hospital in Chicago, and I wish to bring that toyour attention.
I just answered an invitation to submit a manuscript on this sub-ject for publication. The availability of the data and the point ofdeparture in the abstract stimulated me to prepare two slides topresent to you this morning.
(slide) We have operated on 74 patients with aneurysm or dis-section or both of the ascending aorta, associated with, or commonlycausing, aortic regurgitation in the past ten years. Most of thesepatients had an aneurysm. Although a variety of operative procedureshave been employed for correction of these lesions, compositegrafting, as beautifully demonstrated by Dr. Kouchoukos, has beenthe most popular operation in recent years. I was equally gratifiedto note that among 19 patients in whom this technique was usedthere was no hospital mortality. I believe that the new method ofmyocardial preservation, particularly with the use of a potassiumcardioplegic solution, has improved our operative results in thisparticular area.
The difference in our experience relates to the second group ofpatients with aortic dissection, and particularly those with acutedissection. (slide) As you note, of 19 patients with acute dissectionof the aorta, in only two was the aortic valve replaced. In theremaining 17 patients valve competence was restored, either byresection and replacement of a segment of the ascending aorta or, ineight patients, by primary repair without prosthetic materials.Only one patient returned with a recurrent aneurysm and regurgi-
tation some eight years after the first operation and had a successfulsecond procedure.There have been three late deaths in this group, none related
to the operative technique chosen. I do not believe we have usedcomposite grafting in acute dissection, and I feel strongly that itshould only be used under exceptional circumstances.
DR. HENRY T. BAHNSON (Pittsburgh, Pennsylvania): The specialproblems associated with aneurysm of the ascending aorta have to dowith myocaridal protection that is necessary during the necessarilylong period when the heart must be deprived of its normal bloodsupply, with bleeding from the multiple and, later, largely in-accessible lines of suture to abnormal tissue.
Cold cardioplegia seems to be the answer to myocardial pro-tection, and Dr. Kouchoukos' group has shown that sewingtogether the trimmed aneurysm back over the prosthesis is onegood answer to the hemorrhage.
Probably even more meticulous anastomoses are still required withthis technique, because there have been a number of reported in-stances in which hematoma formed underneath the reconstructedwall, leading to further trouble. Probably the sewing of the coronaryarteries to the prosthesis without separating them as a movabletransplanted button has something to do with the lack of obstructionto the coronary arteries, the anastomoses, I think, are a littleharder to do under these circumstances.
At the beginning of this study in 1974, the Birmingham groupset out to evaluate this technique of composite replacement of theaortic valve and ascending aorta, and their report now is in con-
