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Ann Thorac Surg 2004;78:767-772
© 2004 The Society of Thoracic Surgeons
a Division of Cardiac Surgery, Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, USA
b Howard Hughes Medical Institute, Chevy Chase,, USA
c Division of Pediatric Cardiology, Baltimore, MD, USA
d Division of Adult Cardiology, the Johns Hopkins Medical Institutions, Baltimore, Maryland, USA
Accepted for publication March 16, 2004.
* Address reprint requests to Dr Gott, 618 Blalock Building, The Johns Hopkins Hospital, 600 N Wolfe St, Baltimore, MD 21287, USA
vgott{at}csurg.jhmi.jhu.edu
Presented at the Fiftieth Annual Meeting of the Southern Thoracic Surgical Association, Bonita Springs, FL, Nov 13–15, 2003. *Recipient of the 2003 Hawley H. Seiler Resident Award.
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Abstract |
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METHODS: A retrospective clinical review was undertaken using hospital records, clinical and echocardiographic, computed tomography, magnetic resonance imaging data, and telephone interviews with patients and their physicians.
RESULTS: Between July 1994 and December 2002, 65 patients (46 adults and 19 children) underwent a valve-sparing operation for aortic root aneurysm. Forty-four of the patients had the Marfan syndrome; the remaining 21 had either a nonspecific connective tissue disorder (14 patients) or a miscellaneous disease process such as Ehlers-Danlos syndrome (7 patients). Fifty-eight (89%) had a David II (remodeling) procedure and 7 had a David I (reimplantation) procedure. The DePaulis "Valsalva graft" was used in six of the David I patients. There were no operative or hospital deaths; only one late death occurred in an adult due to salmonella meningitis. Overall, survival was 100% at one year and 98% at 3 and 5 years. Ten patients (7 adults and 3 children) developed significant late aortic insufficiency (AI). Nine of these patients had a David II procedure and in 8 of these cases, AI was secondary to significant late annular dilatation. One of the 10 patients developed late AI 8.2 years after a David I procedure; his AI was secondary to aortic leaflet extension and prolapse. Six of the 10 patients who developed significant late AI required aortic valve replacement (4 adults and 2 children). Freedom from late aortic valve replacement (AVR) in this series of 65 patients was 91% at 3 and 84% at 5 years. At the close of this study, 58 patients were New York Heart Association (NYHA) class I and 6 were NYHA class II; no patients were class III or IV. There were no episodes of endocarditis or clinically significant thromboembolism.
CONCLUSIONS: Valve-sparing operations provide satisfactory results for many patients with an aortic root aneurysm, but the David II remodeling procedure has a greater risk of late annular dilatation and AI. The David I reimplantation procedure utilizing the DePaulis Valsalva graft may obviate this problem.
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Introduction |
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TopAbstractIntroductionPatients and methodsResultsCommentDiscussionAcknowledgmentsReferences |
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| The Hawley H. Seiler Resident Award is presented annually to the resident with the oral presentation and manuscript deemed the best of those submitted for the competition. This Award was inaugurated in 1997 to honor Dr Seiler for his contributions and dedicated service to the Southern Thoracic Surgical Association.
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Aortic root replacement is often performed for aneurysms of the ascending aorta and aortic sinuses, as well as for dissection, endocarditis and a host of other diseases involving the base of the aorta. Traditionally, operations to replace the aortic root have included replacement of the aortic valve; these operations have been performed with low operative mortality and low late morbidity. However, concomitant valve replacement usually mandates chronic anticoagulation for mechanical prostheses or reoperation for degeneration of bio-prostheses, and therefore may not be acceptable to all patients. Operations that replace the aortic root yet preserve the valve have been developed by pioneers such as Magdi Yacoub [1] and Tirone David [2, 3] in an effort to improve quality of life for many patients. These operations are still in evolution and long-term results are not yet known.
In this article we review our total experience with valve-sparing (VS) root replacement in 46 adults and 19 children.
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Patients and methods |
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Approval for this clinical study was obtained from the Johns Hopkins Institutional Human Research Committee on April 24, 2002.
Postoperative management
Routine long-term management following the VS procedures included aspirin for anticoagulation and ß-blockers to minimize hemodynamic stress. Antibiotic prophylaxis for endocarditis was also recommended longterm.
Statistical methods
Actuarial survival analyses were calculated using the Kaplan-Meier method; in addition, freedom from 3 to 4+ aortic insufficiency (AI) and freedom from aortic valve replacement (AVR) were calculated. Due to the small number of patients early-on in the series, 5 years of actuarial follow-up are reported. Statistical computations were made using SPSS statistical software (Chicago, IL).
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Results |
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TopAbstractIntroductionPatients and methodsResultsCommentDiscussionAcknowledgmentsReferences |
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The primary indication for aortic root surgery in both adults and children was aneurysmal dilatation of the ascending aorta. Two adults underwent urgent VS surgery for a chronic DeBakey I dissection arising in the root aneurysm.
Two adult patients had mitral valve repair 6 and 10 years before the VS procedure. One 8-year-old child came to VS surgery with significant mitral regurgitation and had concomitant mitral valve repair. Three adults required concomitant coronary artery bypass at the time of the VS procedure.
Operative results
There were no operative or hospital deaths (Table 1), and no significant perioperative morbidity. The one 8-year-old child who had concomitant mitral valve repair had an uneventful postoperative course, as did the two adults who had concomitant repair of their DeBakey I dissections.
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Fifty-five of 58 patients (94.8%) who did not require a late AVR had an echocardiogram, CT, or MRI within 12 months of study closure. Seven of 45 long-term adults developed late 3 to 4+ AI (Table 2). Four of these patients required late AVR, and 3 patients with 3+ AI at the close of this study are being followed closely with serial echocardiograms. Six of the 7 adults with late significant AI had a David II procedure and 1 had a standard David I operation. This latter patient had 2+ AI preoperatively and required an AVR 8.2 years after his David I repair. At the time of his AVR, there was no annular dilatation and the AI resulted from extension and prolapse of all 3 aortic leaflets. Two of 3 adults who required a late AVR following a David II operation, had significant annular dilatation secondary to splaying of the fabric "tongues" at the base of the Dacron graft; late AVR in the third adult was required for a combination of moderate aortic annular dilatation and aortic leaflet prolapse. The 3 adults in Table 2 with 3+ late AI (and no AVR) had significant annular expansion on their echocardiograms at the close of the study. Excluding the 7 adults in Table 2 with late 3 to 4+ AI, 30 had 0 to 1+ late AI, and 8 had late 2+ AI.
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The incidence of late 3+ and 4+ AI and late AVR in our 19 children undergoing VS procedure is depicted in Table 3. Sixteen of 19 children had a David II repair; 3 children with 1 to 2+ preoperative AI had a DePaulis Valsalva graft with a David I repair. As noted in this Table 3, 2 children required late AVR and a third child, who was 1.5 years old at the time of his David II procedure, currently has 3+ AI. This child had an aortic root diameter of 3.0 cm at the time of the David II procedure; he was NYHA class II at the close of study but may eventually require an AVR. The two children requiring late AVR had marked annular dilatation at the time of their second operative procedure; both of these children were NYHA class I at late follow-up. Overall, at the close of the study, 16 children were NYHA class I and 3 were NYHA class II. It is important to note that the 3 children with late significant AI had preoperative aortic roots that were 4.8, 4.7 and 3.0 cm in diameter and all 3 had a David II remodeling procedure. Freedom from significant AI (AI > 2+) in 19 children was 71% at 3 and 5 years; freedom from late AVR in this group was 83% at 3 and 5 years.
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Comment |
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TopAbstractIntroductionPatients and methodsResultsCommentDiscussionAcknowledgmentsReferences |
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Several years later, David introduced a modified remodeling procedure (David II) because of reports of aortic leaflet damage from impingement against the Dacron graft with the David I operation [3]. The David II procedure was then widely adopted in many cardiac surgical centers and was, in fact, the primary VS operation used at our hospital over the last 10 years.
We have been gratified that there has been no 30-day mortality in our patients undergoing a VS procedure. Late clinical results in this series similarly have been encouraging: 58 patients are NYHA class I at late follow-up, and the remaining 6 patients were NYHA class II. There was only one late death, an adult who died from salmonella meningitis 1.3 years after surgery.
However, the most troubling late complication has been valvar insufficiency. Seven of our adult patients developed late 3 to 4+ AI with 4 of these patients requiring an AVR. Six of 7 patients had the David II remodeling procedure as depicted in Table 2. In 5 of 6 patients, AI resulted from significant annular dilatation secondary to splaying of the 3 Dacron "tongues" at the base of the graft. The sixth David II patient developed late AI from a combination of moderate annular dilatation and aortic leaflet prolapse. The one patient in this overall series who had a standard David I reimplantation procedure was an adult who required an AVR after 8.2 years for aortic leaflet prolapse. Because of the reimplantation technique, this patient had no annular dilatation at the time of his AVR.
Based on the data presented in Table 2, 6.9% of 29 patients who had 0 to 1+ AI before their VS procedure developed late 3 to 4+ AI, whereas 31.3% of the patients with 2+, 3+ and 4+ AI before their VS procedure developed late significant AI (4.5 times greater incidence in this group than in patients with 0 to 1+ preoperative AI).
Three of 16 children with the David II procedure developed significant late aortic insufficiency; two required AVR 1.8 and 2.6 years postoperatively. The latter patient also required concomitant mitral valve replacement. A third child who underwent a valve-sparing procedure at age 1.5 years is currently 3.8 years postoperative and has 3+ aortic insufficiency. Just as in the majority of our adult patients, late significant AI developed in these children secondary to annular dilatation (Table 3).
Similar to our experience, David noted a moderate incidence of late AI among David II patients and subsequently returned to his reimplantation technique. In order to avoid the potential problem of leaflet damage with the reimplantation procedure, he created aortic sinuses in the graft by plicating it at the levels of the aortic annulus and the sinotubular junction [10]. In a more recent paper [11], David reported 8-year freedom from moderate/severe AI of 55% ± 6% with the remodeling technique and 90% ± 6% with the reimplantation technique. He also reported exclusive use of the reimplantation technique with neo-aortic sinuses in the sleeve graft over the last 2 years.
The concept of a tubular ascending aorta graft with prefashioned neo-sinuses has been further developed by DePaulis, who designed a commercially available graft with this configuration [4]. Because of our concern over late AI in our patients after the David II remodeling procedure, the senior author (DEC) has used the new DePaulis graft exclusively since August 2002 (the last 5 months of this study) with excellent results. In fact, all 6 patients (3 adults and 3 children) who had the David I reimplantation procedure using the DePaulis Valsalva graft have either no or only mild late aortic insufficiency. Since closure of this study, an additional 19 patients at our institution have had the David I reimplantation technique using this graft. Late clinical followup has been short for our 25 patients with the DePaulis graft, but there has been no significant AI in any of these patients.
Optimal timing for elective prophylactic aortic root replacement, and more specifically, use of the VS procedure for patients with aortic root aneurysms, remains controversial. In adults with aortic root aneurysm, it has been our policy to recommend operative intervention when the aneurysm reaches a diameter of 5.5 cm, but if there is a family history of aortic dissection, we recommend surgery at 5.0 cm. These guidelines have also been used for patients undergoing the Bentall composite graft procedure. If a VS procedure is planned, we believe it is important to intervene before development of significant aortic insufficiency; it may be appropriate to recommend operative intervention for aneurysms less than 5.0 cm when signs of progressive aortic insufficiency appear.
Our recommendation for operative intervention in children with aortic root aneurysm has been discussed in a recent report [12]. In adolescents, we use the same guidelines as for adults. For children 12 years or younger, surgical intervention is recommended if (1) there is an increase in aortic root diameter 1 cm or more over 12 months, or (2) if the root is larger than 5 cm, or (3) if there is progressive aortic insufficiency. The presence of significant mitral insufficiency in children may also be a major determinant operative intervention, and lead to an earlier procedure on the aortic root. Outgrowth of the Dacron graft used in our 19 children has not been a problem. Graft diameters for 4 of our pediatric patients 12 years and younger were 28 mm, 24 mm, 24 mm, and 18 mm in a child 1.5 years of age; we have had no evidence of late morbidity related to patient-prosthesis mismatch.
The VS operation is currently our procedure of choice for both children and adults undergoing operative intervention for aortic root aneurysms. Absence of early mortality and the low incidence of late morbidity among the 64 long-term survivors have been gratifying. Certainly, if long-term results with the VS procedure prove comparable to those with the Bentall composite graft, we feel there is a clear advantage in this procedure that eliminates life-long anticoagulation. However, a concerning late incidence of valvular incompetence makes caution appropriate, and the time-tested Bentall procedure has not been abandoned. It is hoped that recent technical modifications in the VS procedure will address these concerns and yield a procedure with comparable durability to the Bentall.
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Discussion |
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TopAbstractIntroductionPatients and methodsResultsCommentDiscussionAcknowledgmentsReferences |
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How important are the sinuses? We work to create them, but we are not sure of their value. Could you elucidate? What is the mechanism of aortic insufficiency? Specifically, can you predict it preoperatively? And finally, when you resort to the Bentall procedure as the primary operation, does severe pre-op aortic insufficiency influence your choice of operation? I appreciate this excellent report.
DR BETHEA: Thank you, Dr Kron, and thank you for those excellent questions. In terms of the first question, how important are the sinuses, we feel that the sinuses are very important. In 2000, Cochran and his group presented a paper in which they studied aortic valves in a cylindrical structure similar to what you would find with the David I reimplantation procedure and showed that on very finite analysis of the valves, they actually had suffered some damage and this, they hypothesized, could lead to valvular incompetence. Also if you look at nature, the circulatory system, whether valves are in the arterial system or the venous system, every valve is accompanied by a sinus.
So with those things in mind, we agree with David, who originally went away from his David I reimplantation procedure to his remodeling procedure. He has since gone back to reimplantation because of aortic insufficiency with his remodeling procedure and has only used reimplantation procedures in the last several years. Likewise at our institution, our procedure of choice is now the David I reimplantation procedure with the Valsalva graft. We have done 25 patients now, and although we have only been doing them since May of 2002, there has not been any sign of aortic insufficiency on postoperative echoes.
In terms of the second question that you asked; what is the mechanism of late aortic insufficiency, that really depends on the operative procedure that you are talking about. In the David I operation, it really goes back to what we have already discussed, and that is the possible valvular damage that takes place, and, as I mentioned earlier, we feel that David's early formula for estimating appropriate graft diameter was based on normal aortas, and clearly this patient population doesn't have normal aortas; we feel that it probably resulted in an undersized graft with poor coaptation of the aortic valves. This occurred in our patient approximately 8.3 years after his initial operation, and that is the only one of our David I's that has had valvular incompetence.
In terms of the David II's, it appears that most of our children with significant AI have had problems about 2 years after their operation; it appears to be a stretching and continued dilation of the subannular triangles, which then leads to continued annular dilation with splaying of the Dacron graft and eventual valve leaflet stretching and incompetence. We have echo data which actually shows this, and although about 12 of the children have 0 to 1+ aortic insufficiency, their aortic annulus measures greater than 99 percentile for their body surface area.
And then finally the last question is when do we resort to a Bentall. We actually still feel that the Bentall is an excellent operation with low morbidity and mortality, and it has obviously set the bar very high for any future aortic procedures. There are certain instances at our institution when we do use the Bentall exclusively. One of those is when the patient has significant mitral valve insufficiency where the valve is so incompetent it can't be repaired and we use a mitral valve prosthesis.
Another situation is in acute aortic dissection. In that situation, we feel clinically it is just too risky a clinical scenario not to place a Bentall graft. Another clinical situation would be in the massively dilated aortic annulus when the annulus is so dilated that it doesn't appear that the valve will last for a long duration. Dr Cameron, I believe uses a criteria of about 
32 mm. And then finally, the first step in the operation is transection of the aorta and he then puts stay sutures in the commissures, and then looks at the valve before he decides on which procedure to use. If the valve appears to be competent, he proceeds with a valve sparing, and then lastly, in the operating room, after he has repaired, he tests the valve again, and if he was unhappy with it, he will replace it. I am only aware of one patient in whom that has occurred.
DR LARS G. SVENSSON (Cleveland, OH): A couple of questions. What are you doing as far as sizing now that you are using the Vascutek graft? Do you use a formula and do you think that it is still applicable? We have gone away from trying to calculate the size and instead we use a 28 or a 38 graft, but we tie it around a Hegar's dilator that is appropriate for the patient's body surface area. We published a how-to-do-it paper in The Annals about this method that has worked very well for us (November 2003).
A comment about remodelings. When we do remodelings, which I prefer to use for bicuspid valves, we put a Hegar in the left ventricular outflow tract and tie the sutures down around the Hegar. We hope that this might prevent some of the problems that occur late with the remodelings and the splaying of the graft.
The other question I have is how many of these valves did you actually repair the valve before you actually remodeled or reimplanted them. We often repair perforations or put in Cabrol sutures and obviously for bicuspid valves we plicate one of the leaflets? Perhaps you could comment on that aspect, too. Thank you.
DR BETHEA: Thank you for those excellent questions. In terms of sizing the graft, we don't use a formula. We actually try to basically evaluate it at the sinotubular junction. And then in terms of how many of the valves do we actually remodel in any way, I don't have that data. I would have to look that up.
DR W. STEVES RING (Dallas, TX): Could you comment on the David II procedures that did develop aortic insufficiency? Do you have any experience with the annular reinforcement at the level of the base of the sinuses and did you see aortic insufficiency in that population?
DR BETHEA:When we initially started doing the David II we didn't reinforce, but then we quickly went to reinforcing, and we still saw splaying of the annulus, even with reinforcement.
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Acknowledgments |
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TopAbstractIntroductionPatients and methodsResultsCommentDiscussionAcknowledgmentsReferences |
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