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Eur J Cardiothorac Surg 2008;34:42-47. doi:10.1016/j.ejcts.2008.04.005
Copyright © 2008, European Association for Cardio-thoracic Surgery. Published by Elsevier. All rights reserved.
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Intermediate-term results after the aortic valve replacement using bileaflet mechanical prosthetic valve in children

Munetaka Masudaa,*, Hideaki Kadob, Yusuke Andob, Akira Shioseb, Toshihide Nakanob, Kouji Fukaec, Yoshihisa Tanouec, Ryuji Tominagac

a Department of Surgery, Yokohama City University, Fukuura 3-9, Kanazawa-ku, Yokohama 236-0004, Japan
b Department of Cardiovascular Surgery, Fukuoka Children Hospital, Japan
c Department of Cardiovascular Surgery, Kyushu University, Japan

Received 26 August 2007; received in revised form 31 March 2008; accepted 9 April 2008.

* Corresponding author. Tel.: +81 45 787 2644; fax: +81 45 786 0226. (Email: mmasuda{at}yokohama-cu.ac.jp).


   Abstract
Top
 Abstract
1. Introduction
 2. Patients and methods
 3. Results
 4. Discussion
 Appendix A
 References
 
Objective: Intermediate/long-term results after aortic valve replacement using bileaflet mechanical valve in children should be clarified as a standard of treatment of aortic valve disease in children. Methods: Forty-five patients aged under 15 years underwent 46 aortic valve replacements using bileaflet mechanical prosthetic valve. Patients’ ages ranged from 1 to 15 years (9 years as a median value), and follow-up period was 9.2 years as a median value (maximum 19 years). Results: In situ valve replacement was performed in 21 procedures, while annular enlargement was required in 25 procedures (Nicks 10, Yamaguchi 3, Manouguian 2, Konno 10). All patients except two received prosthesis 19 mm or larger in size. There was one operative death and two late deaths. Two episodes of cerebral infarction, two valve thrombosis, two re-operations, one infective endocarditis, and one sudden death were recognized as valve-related complications in five patients. The reasons for re-operation were prosthesis-patient mismatch in one (Ross procedure) and valve thrombosis in one (re-replacement). At 15 years after the operation, re-replacement free rate, valve-related event free rate and actuarial survival rate were 94 ± 4%, 86 ± 6% and 92 ± 4%, respectively. The transprosthetic flow velocity estimated by Doppler echocardiography at the final follow-up was well correlated with manufactured valve area index (cm2/body surface area). Conclusions: Although aortic annular enlargement was required in more than half of the cases, intermediate-term results after aortic valve replacement using bileaflet mechanical prosthetic valve in children was satisfactory. Indications for alternative treatment such as Ross procedure might be considered in limited cases.

Key Words: Mechanical prosthetic valve • Children • Aortic valve replacement • Ross procedure • Bileaflet mechanical prosthetic valve • Aortic annular enlargement


   1. Introduction
Top
 Abstract
 1. Introduction
2. Patients and methods
 3. Results
 4. Discussion
 Appendix A
 References
 
Aortic valve procedure in children is sometimes necessary not only for congenital malformation of the aortic valve but also many kinds of cardiac malformations such as aortic valve deformation associated with ventricular septal defect, deterioration of the neo aortic valve after the arterial switch operation for the transposition of the great arteries, and so on. Although numerous efforts by cardiac surgeons have been made to repair the pathological regions of the aortic valve, reparative procedure of the aortic valve is not always feasible. The selection of the most appropriate substitute for the aortic position in children is still controversial.

There are four types of substitutes available for the aortic position at the moment. Porcine bioprosthesis and bovine pericardial bioprosthesis are considered to be good substitutes for elderly people because of their excellent anti-thrombogenesity, while they are considered unsuitable for children because of their poor durability in young patients [1–4]. Allograft has been implanted especially in small children because of its variety of size, excellent anti-thrombogenesity and good flexibility. However, allograft also has the disadvantage of limited durability due to early calcification in young recipients and limited availability in the market [3,5]. Mechanical valve requires lifelong cumbersome anticoagulation, while it shows an excellent long-term performance with relatively low incidence of complication in children [4,6,7].

There has been increasing enthusiasm for pulmonary autograft (Ross procedure) for aortic valve replacement in children and adolescents. It shows good hemodynamic performance, freedom of anticoagulation and hemolysis, and is considered to have the ability to grow [3,4,8–11]. However, in addition to the complexity of the insertion technique and the creation of a new pathology in the normal right ventricular outflow tract, long-term performance of the pulmonary valve in the systemic circulation is still unknown.

In the process of the selection of a substitute for the aortic position in children, not only surgical outcomes but also long-term results should be considered carefully. In this study, we retrospectively analyzed our intermediate-term outcome of recent bileaflet mechanical prosthetic valve replacement at the aortic position in children.


   2. Patients and methods
Top
 Abstract
 1. Introduction
 2. Patients and methods
3. Results
 4. Discussion
 Appendix A
 References
 
Between 1988 and 2006, 45 children under age of 15 years underwent 46 aortic valve replacements using bileaflet mechanical prosthetic valves at the Fukuoka Children Hospital or at the Kyushu University Hospital. Age at the time of implantation of the prosthesis ranged from 1 year to 15 years (median, 9 years of age), and body weight ranged from 5.3 kg to 70 kg (median, 31.9 kg). There were 32 males and 13 females. Valve pathology was aortic regurgitation in 25 cases, aortic stenosis in 11 cases, and combination of aortic regurgitation and stenosis in 9 cases. Twenty patients underwent 31 previous cardiac procedures (Table 1 ). All prostheses were positioned in the sub-coronary position. Types of implanted prosthetic valve were St. Jude Medical Standard in 15, St. Jude Medical Hemodynamic Plus series in 24, St. Jude Medical Regent series in 1, CarboMedics Standard in 4, CarboMedics Reduced series in 1, and On-X valve in 1 (Table 2 ). The selection of prosthesis was dependent on the patient's aortic annular size and situation of the Japanese market and surgeon's preference. Thirty-two patients underwent 39 concomitant procedures including 25 aortic annular enlargements (Nicks procedure [12] in 10, Yamaguchi procedure [13] in 3, Manouguian procedure [14] in 2 and Konno procedure [15] in 10) (Table 3 ).


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  		Table 1 Previous cardiac procedures
 

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  		Table 2 Prosthetic valve types and size
 

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  		Table 3 Concomitant procedures
 
Postoperative anticoagulation was achieved by intra-venous administration of heparin sodium (400 U/kg per day), with subsequent oral intake of aspirin (5 mg/kg per day) until 1998, and oral intake of warfarin potassium in a dosage to maintain the value of Thrombotest within the range between 10% and 20% (a prothrombin time-international normalized ratio level between 2.5 and 1.8) since 1998.

Patients’ follow-up was done either by referencing patients’ hospital records or through direct telephone calls. Follow-up period ranged from 1 month to 19.1 years (median; 9.2 years) with complete follow-up rate of 95%. Thirty-seven Doppler echocardiography images including the value of transprosthetic flow velocity were obtained within a 1-year period before the final follow-up. The definition of the events during the follow-up was according to the guideline for reporting valve-related mortality and morbidity after cardiac valvular operations by Edmunds et al. [16].

All data in the text are expressed as the mean ± standard deviation. Time-related changes in survival, freedom from re-replacement of aortic valve and valve-related events were analyzed with the Kaplan–Meier method. Statistical analysis was made using StatView software (Abacus Concept, Inc, Berkeley, CA). A p-value equal or less than 0.05 was considered statistically significant.


   3. Results
Top
 Abstract
 1. Introduction
 2. Patients and methods
 3. Results
4. Discussion
 Appendix A
 References
 
Fig. 1 shows the size of the prosthesis and the types of annular enlargement plotted by body weight at the time of initial implantation of the bileaflet mechanical prosthetic valve. Application of various type of annular enlargement enabled the surgeons to implant a prosthesis 19 mm or larger in size except for two patients.


Figure 1
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  		Fig. 1. The size of prostheses and the type of insertion technique plotted by body weight of the patients at the time of initial implantation of the aortic prosthesis. (*): Converted to Ross–Konno procedure due to prosthesis-patient mismatch associated with pannus formation. (#): Re-replacement of prosthetic valve to a new mechanical prosthetic valve St. Jude Medical Regent series 19 mm due to valve thrombosis associated with pannus formation.

 
There was one operative death. This patient was diagnosed as truncus arteriosus with single coronary artery, and previously had undergone Rastelli type procedure with external conduit between the right ventricle to the pulmonary artery. She underwent aortic valve replacement using Nicks procedure for annular enlargement associated with conduit replacement at 7 years of age. We lost her in spite of the application of postoperative circulatory support for severe postoperative heart failure. There were two late deaths. The reason for late death was sudden death in one patient 6 years after the in situ aortic valve replacement using St. Jude Medical valve Hemodynamic Plus series 19 mm. Autopsy revealed neither apparent evidence of cerebral infarction nor intrinsic/extrinsic structural valve deterioration. The other patient died due to heart failure 5 months after the aortic valve replacement using St. Jude Medical valve Hemodynamic Plus series 21 mm with Nicks procedure.

As valve-related complications, two episodes of cerebral infarction, two valve thrombosis, two re-replacement of aortic valve, one infective endocarditis, and one sudden death were recognized in five patients. Cerebral infarction occurred in one patient at 1998 when our anticoagulation regimen was aspirin only. After changing our anticoagulation regimen to warfarin, one cerebral infarction was recognized due to withdrawal of warfarin by patient himself. Valve thrombosis occurred twice in the same patient with a therapeutic level of anticoagulation with warfarin. Thrombolysis was successful at the first time (4 years after the aortic valve replacement), while re-replacement of the aortic valve was required at the second time (4.8 years after the aortic valve replacement). Pannus formation under the prosthesis was also observed at the time of re-replacement. Another patient, who had St. Jude Medical valve Hemodynamic Plus series 17 mm with Yamaguchi procedure, required a Ross–Konno procedure 8 years after the initial aortic valve replacement due to prosthesis-patient mismatch associated with pannus formation.

Actuarial survival rate was 92 ± 4% at 15 years after the initial aortic valve replacement with bileaflet mechanical valve. Freedom from re-replacement of aortic valve and valve-related events was 94 ± 4% and 86 ± 6% at 15 years, respectively (Fig. 2 ).


Figure 2
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  		Fig. 2. Freedom from events. ({circ}): Actuarial survival, ({square}): freedom from re-replacement of aortic prosthetic valve, ({triangleup}): freedom from valve-related events.

 
Maximum transprosthetic flow velocity (V max) estimated by follow-up Doppler echocardiography was well correlated with prosthetic valve orifice area index (manufactured geometric prosthetic valve area divided by patient's body surface area) at the time of examination (V max = –67.9 x valve orifice area index + 338.5; r = 0.33; p = 0.043; Fig. 3 ). V max remained under 300 cm/s in all patients with manufactured valve area index over 1.0 cm2/m2 except for two who required re-replacement of aortic valve due to pannus formation associated with valve thrombosis or prosthesis-patient mismatch. Their V max exceeded 400 cm/s at the time of re-replacement.


Figure 3
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  		Fig. 3. Correlation between manufactured valve area index and V max. V max: maximum transprosthetic valve flow velocity. (*): Converted to Ross–Konno procedure due to prosthesis-patient mismatch associated with pannus formation. (#): Re-replacement of prosthetic valve to a new mechanical prosthetic valve St. Jude Medical Regent series 19 mm due to valve thrombosis associated with pannus formation.

 

   4. Discussion
Top
 Abstract
 1. Introduction
 2. Patients and methods
 3. Results
 4. Discussion
Appendix A
 References
 
Although there has been increasing interest in the pulmonary autograft implantation at the aortic position (Ross procedure) in children and adolescents, there are still controversies regarding the selection of substitutes at the aortic position in children.

Porcine bioprosthesis and bovine pericardial bioprosthesis do not require permanent anticoagulation, however, they have been almost abandoned for clinical use in small children because of their very early degeneration, calcification and structural failure in young recipients [1–4]. Allograft allows implantation of small size substitutes for neonates and infants, in addition there is the unnecessity of anticoagulation and excellent freedom from anticoagulation-related complications. However, allograft shares the same disadvantage of limited durability as xenograft has [3,5].

Pulmonary autograft (Ross procedure) has become the first choice of aortic valve replacement in children and adolescents in some institutes [3,4,8–11]. Pulmonary autograft shows excellent hemodynamic performance, freedom of anticoagulation and hemolysis, and decreased susceptibility to endocarditis. Pulmonary autograft is also known to have the potential for growth. However, the Ross procedure is a technically demanding procedure, and reoperation for bleeding and postoperative conduction abnormality is not as rare as early complications [11]. Freedom from autograft dysfunction including autograft insufficiency 3+ or more ranges from 75% to 100% depending upon the duration of follow-up [11]. Elkins et al. [17] reported freedom from autograft replacement of 93% and freedom from severe autograft insufficiency or valve-related death of 90% at their 12-year follow-up. The autograft insufficiency is one of the leading cause of reoperation in Ross procedure, and several factors are implicated as risk factors such as preoperative diagnosis of aortic insufficiency, presence of dilated aortic annulus, bicuspid aortic valve, rheumatic heart disease, technical imprecision, the type of insertion, inherent disease of the pulmonary valve, and so on [11].

Elkins et al. [17] reported a freedom from right ventricular outflow tract homograft replacement of 90% at 12 years for children. Rates of freedom from right ventricular outflow tract obstruction were also similar for several authors [18–21]. Because of the diminishing availability of homograft, several conduits are used to reconstruct the right ventricular outflow tract, however, their durability seems to be worse than homograft [11]. Finally, Elkins et al. [17] reported freedom from all valve-related morbidity at 79% at 11 years.

Aortic valve replacement using mechanical prosthetic valves in children often require annular enlargement to insert commercially available prosthesis [6,7]. Nicks procedure [12] enables insertion of prosthesis one size bigger than that of in situ insertion, while Konno procedure [15], Manouguian procedure [14] and Yamaguchi procedure [13] enable insertion of prosthesis two sizes bigger than that of in situ insertion. Konno procedure requires incision of the ventricular septum that might cause ventricular dysfunction or conduction abnormality. In Manouguian procedure, the incision is extended to the anterior mitral leaflet that might cause the mitral insufficiency. Yamaguchi procedure is now our choice of procedure because it does not damage either ventricular septum or mitral leaflet.

Our institutional anticoagulation strategy changed from aspirin to warfarin since 1998 when we had cerebral infarction in one patient. Since we started the new anticoagulation strategy with warfarin, we have not seen any thrombo-embolic events except for two cases, one valve thrombosis associated with pannus formation and the other with cerebral infarction due to warfarin withdrawal by the patient himself. There was no major anticoagulation related hemorrhage. Our freedom from anticoagulation-related events (thrombo-embolism and hemorrhage) at 15 years was 92 ± 4%.

In our study, all patients except for two received bileaflet mechanical prosthetic valve 19 mm or larger in size along with our vigorous application of annular enlargement at the time of initial implantation. Effective valve orifice area index less than 0.85 cm2/m2 is now considered as a criterion of prosthesis-patient mismatch in adults [22], while effective valve orifice area of the prosthesis is different by researchers. In this study, we measured transprosthetic flow velocity by Doppler echocardiography, and plotted these data according to the manufactured valve area index. This revealed that transprosthetic flow velocity does not exceed 300 cm/s in cases with manufactured valve area index more than 1.0 cm2/m2 except for cases associated with pannus formation. It means that, at least in most of our Japanese patients with small body size even in adults, implantation of St. Jude Medical Regent series 19 mm whose manufactured valve area is 2.39 cm2 may not require further re-replacement of the aortic valve unless massive pannus formation develops. Our speculation was compatible with the result of Shanmugan et al. [7] who reported no re-replacement of prosthesis required when the patient received a prosthesis 21 mm or larger in size. The impact of residual pressure gradient across the prostheses on long-term performance of the myocardium is still controversial. Freedom from re-replacement of aortic valve in our series was 94 ± 4% at 15 years, and was at least compatible with the results of other series with mechanical prosthesis by Shanmugan et al. [7] (92% at 20 years), Alexiou et al. [6] (86.4% at 20 years) and Ruzmetov et al. [4] (84% at 19 years), and was not inferior to the results of pulmonary autograft reported by Elkins et al. [17] (93% at 12 years), Turrentine et al. [2] (88% at 7 years), Laudito et al. [23] (83% at 6.6 years) and Pasquali et al. [21] (81% at 8 years). Actuarial survival rate of 92 ± 4% and freedom from valve related complications of 86 ± 6% at 15 years in our series seems quite acceptable, and these results were compatible with recent results after the Ross procedure [2,4,8,19,20,23]. Long-term survival after the aortic valve replacement using bileaflet mechanical prosthetic valve was satisfactory, and an incident rate of late events was low.

This study is retrospective, and the number of patients is relatively small and the follow-up period is not sufficiently long to be conclusive. Our indication for re-replacement of aortic prosthetic valve has not been well established, although left ventricular outflow tract gradient by Doppler echocardiography greater than 40 mmHg [24] is our indication of re-replacement at this moment. Regardless of these limitations, we believe that our study gives useful information to the surgeons to decide their strategy for aortic valve replacement in children.

In conclusion, intermediate-term clinical results of aortic valve replacement in children using bileaflet mechanical prosthetic valve with aortic annular enlargement if necessary was satisfactory. Good hemodynamic performance of recent commercially available bileaflet mechanical prosthetic valve might avoid further re-replacement of the aortic prosthetic valve. Indication of pulmonary autograft insertion at the aortic position, Ross procedure, might be considered carefully in limited cases such as neonate and infants.


   Appendix A
Top
 Abstract
 1. Introduction
 2. Patients and methods
 3. Results
 4. Discussion
 Appendix A
References
 
Conference discussion

Dr W. Daenen (Linden, Belgium): You remarked that seven patients underwent a valve replacement after an arterial switch. What was the interval between the arterial switch and the valve replacement?

Dr Masuda: I’m sorry, I don’t remember the precise year, but I think these patients received the aortic valve replacement more than 10 years after the arterial switch operation.

Dr C. Sebening (Heidelberg, Germany): I would like to come back a little bit on the point that you just made, Dr Daenen. What is your impression from the cohort of patients after the arterial switch operation as to the mechanism of aortic insufficiency? Many things have been said about it. Was it button-implantation-related or aortic-root-reconstruction-technique-related? What is the impression that you have as to the mechanism of aortic insufficiency in these patients?

Dr Masuda: We assumed that the use of the button technique might be the cause of the aortic regurgitation after the arterial switch operation. We aren’t sure that this is the precise mechanism, but all of our patients who received the aortic valve replacement had the button technique, so we have started to use the trap-door technique in these days.

Dr Daenen: I was very surprised to see that in two patients, full anticoagulation was either not started or stopped. What was the reason for that?

Dr Masuda: Because one patient received aspirin only and the other patient withdrew warfarin by himself.

Dr Daenen: By himself?

Dr Masuda: Yes.

Dr Daenen: And what was the indication to put him on aspirin only?

Dr Masuda: In the initial era we believed that the bileaflet valve does not need warfarin, and after we had the case of cerebral infarction, we changed our strategy to using warfarin.

Dr Daenen: That was a long time ago.

Dr Masuda: Yes.

Dr S. Mohammadi (Montreal, Quebec, Canada): As you mentioned very well, patient-prosthetic mismatch is a very important issue. This is in growing kids. I have a question for you. Do you have any information about the clinical functional class of these patients, because sometimes we just have clinical mismatch in these patients and you don’t need to change it.

Dr Masuda: Almost all patients remained in New York Heart Association functional class I and class II, except for one patient who had a big pressure gradient. We have carefully followed up this patient, but unfortunately this patient moved to another center. I am worried about this patient because we think that this patient should have a redo in the near future.

Dr J. Moll (Lodz, Poland): How large was the group of patients with the arterial switch operation? You had seven patients who needed aortic valve replacement. How large was this group of patients with transposition?

Dr Masuda: In this study group we had only 45 ...

Dr Moll: No, no, this transposition group.

Dr Masuda: For transposition?

Dr Moll: Yes.

Dr Masuda: At this moment I think we have a little bit more than 300 cases for the arterial switch operation.

Dr Moll: Don’t you think that it's a large group of patients who required valve replacement?

Dr Masuda: Yes.

Dr Moll: I’m surprised you said the results were similar. I have done nearly 500 and only one patient needed to have the valve replaced.

Dr Masuda: That might be caused by the technique of the arterial switch operation which I had mentioned before, the button technique.

Dr Moll: You said about 10 years after the operation?

Dr Masuda: Yes.

Dr G. Sarris (Athens, Greece): Before we move on, just a last comment and a brief question. This is an important paper showing very good results of mechanical valve replacement in children. This is a very important contribution, especially given the increasing awareness of long-term problems with root dilatation after the Ross operation. Given these results from your unit, what is your policy now with performing the Ross operation in children? Is there a place for the Ross operation in your practice?

Dr Masuda: It's different for each surgeon, but I myself, I think very small patients, like neonates and infants, might be the candidates for the Ross operation.


   Footnotes
 
{star} Presented at the 21st Annual Meeting of the European Association for Cardio-thoracic Surgery, Geneva, Switzerland, September 16–19, 2007.


   References
Top
 Abstract
 1. Introduction
 2. Patients and methods
 3. Results
 4. Discussion
 Appendix A
 References
 

  1. Mazzitelli D, Guenther T, Schreiber C, Wottke M, Michel J, Meisner H. Aortic valve replacement in children. Are we on the right track?. Eur J Cardiothorac Surg 1998;13:565-571.[CrossRef][Medline]
  2. Turrentine MW, Ruzmetov M, Vijay P, Bills RG, Brown JW. Biological versus mechanical aortic valve replacement in children. Ann Thorac Surg 2001;71:S356-S360.[CrossRef][Medline]
  3. Karamlou T, Jang K, Williams WG, Caldarone CA, van Arsdell G, Coles JG, McCrindle BW. Outcomes and associated risk factors for aortic valve replacement in 160 children. A competing-risks analysis. Circulation 2005;112:3462-3469.[Abstract/Free Full Text]
  4. Ruzmetov M, Vijay P, Rodefeld, MD, Turrentine MW, Brown JW. Evolution of aortic valve replacement in children. A single center experience. Int J Cardiol 2006;113:196-200.
  5. Takkenberg JJM, Klieverik LMA, Bekkers JA, Kappetein AP, Ross JW, Eijkemans MJC, Bogers AJJC. Allografts for aortic valve or root replacement: insights from an 18-year single-center prospective follow-up study. Eur J Cardiothorac Surg 2007;31:851-859.[Abstract/Free Full Text]
  6. Alexiou C, McDonald A, Langley SM, Dalrymple-Hay MJR, Haw MP, Monro JL. Aortic valve replacement in children. Are mechanical prostheses a good option?. Eur J Cardiothorac Surg 2000;17:125-133.[Abstract/Free Full Text]
  7. Shanmugan G, MacArthur K, Pollock J. Mechanical aortic valve replacement. Long-term outcomes in children. J Heart Valve Dis 2005;14:166-171.[Medline]
  8. Lupinetti FM, Duncan BW, Scifres AM, Fearneyhough CT, Kilian K, Rosenthal GL, Cecchin F, Jones TK, Herndon SP. Intermediate-term results in pediatric aortic valve replacement. Ann Thorac Surg 1999;68:521-525.[Abstract/Free Full Text]
  9. Samir K, Riberi A, Kreitmann B, Metras D. The Ross operation as an ideal choice for aortic valve replacement in patients with congenital disease. J Thorac Cardiovasc Surg 2003;125:738-739.[Free Full Text]
  10. Chiappini B, Absil B, Rubay J, Noirhomme P, Funken JC, Verhelst R, Poncelet A, Khoury GE. The Ross procedure: clinical and echocardiographic follow-up in 219 consecutive patients. Ann Thorac Surg 2007;83:1285-1289.[Abstract/Free Full Text]
  11. Raja SG, Pollock J. Current outcomes of Ross operation for pediatric and adolescent patients. J Heart Valve Dis 2007;16:27-36.[Medline]
  12. Nicks R, Cartmill T, Bernstein L. Hypoplasia of the aortic root. The problem of aortic valve replacement. Thorax 1970;25:339-346.[Abstract/Free Full Text]
  13. Yamaguchi M, Ohashi H, Imai M, Oshima Y, Hosokawa Y. Bilateral enlargement of the aortic valve ring for valve replacement in children. New operative technique. J Thorac Cardiovasc Surg 1991;102:202-206.[Abstract]
  14. Manouguian S, Seybold-Epting W. Patch enlargement of the aortic valve ring by extending the aortic incision into the anterior mitral leaflet. J Thorac Cardiovasc Surg 1979;78:402-412.[Abstract]
  15. Konno S, Imai Y, Iida Y, Nakajima M, Tatsuno K. A new method for prosthetic valve replacement in congenital aortic stenosis associated with hypoplasia of the aortic valve ring. J Thorac Cardiovasc Surg 1975;70:909-917.[Abstract]
  16. Edmunds Jr. LH, Clark RE, Chon LH, Grunkemeier GL, Miller DC, Weisel RD. Guideline for reporting morbidity and mortality after cardiac valvular operations. Ann Thorac Surg 1996;62:932-935.[Abstract/Free Full Text]
  17. Elkins RC, Lane MM, McCue C. Ross operation in children. Late results. J Heart Valve Dis 2001;10:736-741.[Medline]
  18. Kouchoukos NT, Masetti P, Nickerson NJ, Castner CF, Shannon WD, Davila-Roman VG. The Ross procedure. Long-term clinical and echocardiographic follow-up. Ann Thorac Surg 2004;78:773-781.[Abstract/Free Full Text]
  19. Hraska V, Krajci M, Haun C, Ntalakoura K, Razek V, Lacour-Gayet F, Weil J, Reichenspurner H. Ross and Ross–Konno procedure in children and adolescent. Mid-term results. Eur J Cardiothorac Surg 2004;25:742-747.[Abstract/Free Full Text]
  20. Al-Halees Z, Pieters F, Qadoura F, Shahid M, Al-Amri M, Al-Fadley F. The Ross procedure is the procedure of choice for congenital aortic valve disease. J Thorac Cardiovasc Surg 2002;123:437-441.[Abstract/Free Full Text]
  21. Pasquali SK, Shera D, Wernovsky G, Cohen MS, Tabbutt S, Nicolson S, Spray TL, Marino BS. Midterm outcomes and predictors of reintervention after the Ross procedure in infants, children, and young adults. J Thorac Cardiovasc Surg 2007;133:893-899.[Abstract/Free Full Text]
  22. Ruel M, Al-Faleh H, Kulik A, Chan KL, Mesana TG, Burwash IG. Prosthesis-patient mismatch after aortic valve replacement predominantly affects patients with pre-existing left ventricular dysfunction. Effect on survival, freedom from heart failure, and left ventricular mass regression. J Thorac Cardiovasc Surg 2006;131:1036-1044.[Abstract/Free Full Text]
  23. Laudito A, Brook MM, Suleman S, Bleiweis MS, Thompson LD, Hanley FL, Reddy VM. The Ross procedure in children and young adults. A word of caution. J Thorac Cardiovasc Surg 2001;122:147-153.[Abstract/Free Full Text]
  24. Kanter KR, Kirshbom PM, Kogon BE. Redo aortic valve replacement in children. Ann Thorac Surg 2006;82:1594-1597.[Abstract/Free Full Text]




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