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J Thorac Cardiovasc Surg 2008;136:472-475
© 2008 The American Association for Thoracic Surgery
Surgery for Acquired Cardiovascular Disease |
a Clinic for Cardiovascular Surgery, University Hospital Berne, Berne, University Berne, Switzerland
b Department of Cardiology, University Hospital Berne, University Berne, Berne, Switzerland
Received for publication October 22, 2007; revisions received January 31, 2008; accepted for publication February 1, 2008. * Address for reprints: Thierry Carrel, MD, Clinic for Cardiovascular Surgery, University Hospital, Freiburgerstrasse, 3010 Bern, Switzerland. (Email: thierry.carrel{at}insel.ch).
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Abstract |
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 Top Abstract IntroductionPatients and MethodsDiscussionReferences |
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Patients and Methods: Between 2006 and 2007, 12 patients (mean age 16 ± 38 years; range 15–38 years) underwent a Ross procedure by this technique. Indications were aortic regurgitation (n = 2), aortic stenosis (n = 5), and combined aortic stenosis and insufficiency (n = 5). A bicuspid aortic valve was present in 9 patients. Balloon valvuloplasty had been performed in 7 patients. Follow-up was performed by clinical and echocardiographic examinations.
Results: No early or late deaths occurred in this small series, and freedom from reoperation is 100%. Echocardiographic follow-up confirmed absence of aortic insufficiency in 11 patients after a mean of 11 months (range 2–30 months). In 1 patient, a small asymmetric regurgitation jet was already observed at discharge echocardiography. As expected, no neoaortic root dilatation was observed during follow-up. All patients are in New York Heart Association class I.
Conclusions: The present technique is a simple and reproducible technical step that does not require significant additional time. Inclusion of the autograft within a root prosthesis may be especially indicated in situations known for late autograft dilatation, namely, bicuspid aortic valve, predominant aortic insufficiency, and ascending aortic enlargement.
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Introduction |
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TopAbstractIntroductionPatients and MethodsDiscussionReferences |
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However, some surgeons and cardiologists criticize the Ross procedure because it turns a single valve disease into a double-valve pathology.1,2
Besides the hypothetical necessity for repetitive interventions on the right ventricular outflow tract (RVOT), midterm to long-term dilatation of the pulmonary autograft in the aortic position is another concern because it may lead to progressive regurgitation of the neoaortic valve when the procedure is performed as a full root replacement.3-6 The Ross procedure may therefore be the source for additional reinterventions of increasing complexity. Hence, some conclude that the long-term performance of the Ross procedure, especially when performed as a full root implant, is the major drawback of this technique.1,7
This article describes our early experience with external reinforcement of the autograft, which is inserted into a prosthetic Dacron graft that exhibits an aortic root design. This technical detail should help to prevent neoaortic root dilatation and autograft regurgitation.
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Patients and Methods |
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TopAbstractIntroductionPatients and MethodsDiscussionReferences |
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The indication was pure aortic regurgitation in 2, aortic stenosis in 5, and combined aortic stenosis and insufficiency in 5 patients. A bicuspid aortic valve was present in 9 patients and balloon valvuloplasty had been performed in 7 patients. The cause of the valve disease was congenital aortic stenosis in all patients. Preoperatively, 8 patients were in New York Heart Association class II and 4 in class III. All patients were operated on electively.
All patients were prospectively followed up by clinical and echocardiographic examinations, which were obtained intraoperatively, before discharge, at 6 months and 1 year, and thereafter yearly. Autograft valve function, homograft or RVOT conduit valve function, and left ventricular function were assessed by M-mode, 2-dimensional echocardiography, and by color flow Doppler sonography.
Operative Technique
All patients were operated on with moderate hypothermic cardiopulmonary bypass and intermittent blood cardioplegia. The autograft root was harvested as described in the original technique with a short muscular rim of RVOT. The diameter of the autograft was determined by standard valve sizers and, subsequently, a 2- to 5-mm larger polyester Valsalva vascular prosthesis (Vascutek woven polyester graft Gelweave; Terumo Cardiovascular Systems Inc, Ann Arbor, Mich) was chosen.
After the prosthesis has been tailored to an appropriate length by leaving only a small rim of about 2 to 3 mm of the proximal skirt (proximal to the artificial root), the autograft is inserted into the vascular prosthesis and fixed with a running suture of 4–0 Prolene polypropylene (Ethicon, Inc, Somerville, NJ) at the distal and proximal ends (
Figure 1). If the height of the autograft is smaller than the Valsalva part of the prosthesis, the proximal skirt can be completely removed to preserve an "artificial" sinotubular junction at the level of the commissures of the autograft. Afterward, a standard technique of complete root replacement is used. The reinforced autograft is sutured at the annular level of the excised aortic valve with continuous running polypropylene. After careful determination of the optimal site for coronary ostial reimplantation, small windows are made into the graft and corresponding buttonholes into the wall of the pulmonary artery (neoaortic root) with an aortic punch. The coronary arteries are reimplanted with a 6–0 running suture between the coronaries and the autograft only; the graft is not included in this suture to avoid blood accumulation between the autograft and the vascular graft in case oozing should occur early postoperatively (
Figure 2). The RVOT is reconstructed with a pulmonary homograft in a conventional fashion, usually during reperfusion.
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Table 1).
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There were no other complications. During early follow-up (up to 30 months so far) no patient required reoperation. Echocardiographic follow-up confirmed absence of aortic insufficiency in 11 patients after a mean of 12 months (range 2–30 months). In 1 patient, an asymmetric regurgitation jet was already observed at discharge echocardiography but had not increased at 1-year follow-up. As expected, no neoaortic root dilatation was observed during follow-up. All patients are in New York Heart Association class I.
Magnetic resonance imaging was performed in 8 of 12 patients and shows physiologic flow dynamics across the pulmonary autograft, very similar to those found in a normal aortic root of healthy control subjects.8
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Discussion |
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TopAbstractIntroductionPatients and MethodsDiscussionReferences |
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Recently, Klieverik and associates7 revealed a worrisome 69% ± 7% rate of freedom from autograft reintervention at 13 years' follow-up. Autograft replacement owing to neoaortic root dilatation was necessary in 22 of 146 patients during a mean follow-up of 8.7 years. Similar rates were observed by Kouchoukos,9 Pasquali,6 and their associates, whereas other studies reported lower rates of reinterventions for autograft dilatation.10,11 Yacoub and colleagues,10 for instance, reported a freedom from autograft reoperation of 92.9% at 10 years with a mean follow-up of 6.2 years. In the most recent published series, Pasquali and coworkers6 showed that a disproportionate enlargement of the neoaortic root was found in younger patients; at 6 years, freedom from neoaortic reintervention was 88% whereas prior ventricular septal defect closure and aortic valve replacement were associated with an increased rate of reintervention.
The reason for these differences is not clear. Histologic studies from dilated autografts showed the following severe structural changes: interruption of the media and a loss of elastin and smooth muscle cells in the vessel wall of the pulmonary autografts.9,12,13 However, it is unclear whether these changes would be commonly observed in all autografts subjected to systemic pressure or whether some of them may have a pre-existing abnormality.14 Concerning the mechanism of autograft degeneration, Yacoub and colleagues10 proposed that the different type of attachment of the pulmonary valve leaflets, which are fixed to the muscular tissue of the RVOT, may contribute significantly to autograft dilatation. In contrast to the aortic valve, where the leaflets are attached to a well-defined crown-like fibrous annulus, muscular tissue of the RVOT extends along the proximal part of each cusp of the pulmonary valve. Inasmuch as the infundibular muscle attached to the autograft may become ischemic after procurement, its support to the region of pulmonary sinuses may be lost. Scalloping of the lower end of the autograft, leaving minimal amount of muscular tissue, and inserting this region inside the aortic annulus may help to minimize the risk of late dilatation.
The original description of the Ross procedure recommended suturing the autograft in a subcoronary position, which did not allow long-term dilatation. Sievers and coworkers15 reported the results with this technique in 347 patients. In 4 patients the autograft had to be replaced, whereas autograft insufficiency of grade III was present in only 4 other patients at the last follow-up. No dilatation of the aortic root was observed at all. The authors concluded that the subcoronary implantation should be the first choice when a Ross procedure is performed. However, a majority of surgeons argue that the subcoronary implantation is technically more demanding, especially in the presence of aortic root calcification and in patients with true bicuspid aortic valve, in whom the ideal geometric positioning of the autograft may be more difficult to define.
A technique similar to the one described in this article has already been described briefly in a review, but the autograft was encased in a straight Dacron prosthetic graft, which however does not allow any pulsatility of the autograft.16 Our modification uses a prosthetic graft with an artificial Valsalva configuration to allow the most physiologic pressure and flow patterns within the autograft with a complete reinforcement of the pulmonary autograft. Wrapping of the pulmonary autograft is not a completely new concept; we17 already described the wrapping technique more than 15 years ago as an adequate technique for older patients with a moderate dilatation of the ascending aorta. Midterm results were very satisfactory and no necrosis of the underlying ascending aortic tissue was found in these patients when redo surgery was necessary because of the migration of the reinforcement graft.
Magnetic resonance flow and pressure studies showed that the pulsatility of the autograft is preserved within each cardiac cycle. The artificial root region of the vascular graft allows some pressure-related pulsatility of the autograft during the cardiac cycle, while preventing dilatation of the autograft when exposed to a systemic pressure in the long term.
In conclusion, the present technique is a simple and reproducible additional step, which does not require significant additional time. Inclusion of the autograft within an aortic root–designed prosthetic graft may help to prevent neoaortic root dilatation and autograft regurgitation and is especially indicated in situations known for late autograft dilatation, namely, bicuspid aortic valve, predominant aortic insufficiency, and ascending aortic enlargement.
Only a close follow-up will definitely be able to demonstrate whether midterm to long-term dilatation of the pulmonary autograft can be avoided through this technique.
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References |
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TopAbstractIntroductionPatients and MethodsDiscussionReferences |
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This article has been cited by other articles:
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  F. Juthier, A. Vincentelli, C. Pincon, C. Banfi, P. V. Ennezat, S. Marechaux, and A. Prat Reoperation After the Ross Procedure: Incidence, Management, and Survival Ann. Thorac. Surg., February 1, 2012; 93(2): 598 - 605. [Abstract] [Full Text] [PDF]
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J. W. Brown, J. W. Fehrenbacher, M. Ruzmetov, A. Shahriari, J. Miller, and M. W. Turrentine Ross Root Dilation in Adult Patients: Is Preoperative Aortic Insufficiency Associated With Increased Late Autograft Reoperation? Ann. Thorac. Surg., July 1, 2011; 92(1): 74 - 81. [Abstract] [Full Text] [PDF]
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 J. A. Bekkers, L. M. A. Klieverik, G. B. Raap, J. J. M. Takkenberg, and A. J. J. C. Bogers Aortic root reoperations after pulmonary autograft implantation J. Thorac. Cardiovasc. Surg., December 1, 2010; 140(6_suppl): S58 - S63. [Abstract] [Full Text] [PDF]
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R. M. Ungerleider, Y. Ootaki, I. Shen, and K. F. Welke Modified Ross Procedure to Prevent Autograft Dilatation Ann. Thorac. Surg., September 1, 2010; 90(3): 1035 - 1037. [Abstract] [Full Text] [PDF]
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F. Juthier, C. Banfi, A. Vincentelli, P. V. Ennezat, T. Le Tourneau, C. Pincon, and A. Prat Modified Ross operation with reinforcement of the pulmonary autograft: Six-year results J. Thorac. Cardiovasc. Surg., June 1, 2010; 139(6): 1420 - 1423. [Abstract] [Full Text] [PDF]
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 F. Al Rashidi, M. Bhat, P. Hoglund, C. Meurling, A. Roijer, and B. Koul The modified Ross operation using a Dacron prosthetic vascular jacket does prevent pulmonary autograft dilatation at 4.5-year follow-up Eur J Cardiothorac Surg, April 1, 2010; 37(4): 928 - 933. [Abstract] [Full Text] [PDF]
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