Aortic root disease after the Ross procedure

PURPOSE OF REVIEW

Autograft root pathology is the most common adverse event late after the Ross operation. Therefore, characterization of prevalence, risk factors and natural history of root disease, as well as identification of preventive and therapeutic strategies, is warranted.

RECENT FINDINGS

Autograft root pathology affects up to one third of long-term survivors of the Ross operation. Root replacement technique and preoperative aortic aneurysm are recurrent risk factors. Any age group, except for infants, may be affected. Dilatation is often progressive leading to valve regurgitation, true aneurysm, and, rarely, dissection. Primary prevention involves avoidance of root technique, graft repalcement of aneurysmal aorta, or modifications of the root technique. Use of beta-receptor antagonist or angiotensin converting enzyme-inhibitors for secondary prevention is still empirical. Indications to resection of root aneurysm are based on maximum root area indexed to body height. Reintervention prior to appearance of relevant valve insufficiency increases likelihood of pulmonary valve preservation. Definition of functional outcome after autograft valve-sparing procedures needs longer follow-up.

SUMMARY

Over a decade after worldwide embracement of the root replacement technique for the Ross procedure, autograft root pathology is emerging as a prevalent complication. Prophylactic and therapuetic strategies are proposed to mitigate the current and future impact of this phenomenon.

Valve-sparing aortic root replacement with repair of leaflet prolapse after Ross operation

The need for reoperation remains a principal limitation of the Ross procedure and most commonly includes replacement of the neo-aortic valve. Valve-preserving aortic root replacement has recently evolved into an increasingly accepted treatment modality for patients with neo-aortic valve regurgitation. Leaflet prolapse, however, may be present, making composite replacement the most frequent choice. Alternatively, valve preservation may be combined with correction of leaflet prolapse. We describe the use of a valve-sparing procedure with correction of leaflet prolapse in a patient with progressive dilatation of the pulmonary autograft and severe regurgitation of the neo-aortic valve.

[Congenital aortic valve stenosis. Current treatment]

OBJECTIVE

Congenital aortic valve stenosis is a common lesion, with an approximate incidence of 5 to 7% of all cardiac malformations and occupies the first place among left heart obstructions. In recent years, many modalities of treatment have been developed. Fetal interventions has evolved in one extreme of life, on the other hand, percutaneous aortic valve replacement is now available for aged adults. In children and adolescents, percutaneous aortic valve valvuloplasty is now more effective with new techniques. The Ross procedure is the first choice treatment in children and young adults with hipoplastic aortic annulus. Considerable medical information has evolved and expanded from these techniques. A review of the indications, optimal timing, and outcomes of these procedures is pertinent.

Is the Ross operation still an acceptable option in children and adolescents?

BACKGROUND

The Ross operation is increasingly accepted as an alternative to conventional valve prostheses for children, adolescents, and young adults. We review patients younger than 20 years of age.

METHODS

Of 404 Ross operations done before November 2004, 60 were young patients with a median age of 12 years (range, 1 to 20 years). The pulmonary autograft technique universally was as a free root. A cryopreserved pulmonary homograft reconstructed the right ventricular outflow tract.

RESULTS

Early postoperative complications were reentry for bleeding in 2 patients and one pacemaker insertion. No thromboembolic or hemorrhagic events occurred during the follow-up of 42 +/- 27 months. Two late deaths occurred, one from myocardial infarction after 3 months and another sudden death after 5 years, probably from critical pulmonary homograft stenosis. Echocardiographic follow-up revealed a median peak gradient of 6.3 +/- 3 mm Hg across the autograft. The median pulmonary homograft peak gradient of 19.1 +/- 13.7 mm Hg was increased to more than 30 mm Hg in 6 patients. Another 6 patients had moderate but clinically insignificant pulmonary homograft regurgitation. Altogether, 6 patients required reoperation for replacement of stenotic homografts. No autograft related reoperation occurred.

CONCLUSIONS

Young patients with the Ross operation had good mid-term autograft function and no perioperative mortality. Factors that justify the choice of the Ross operation for young patients are the normal physiologic hemodynamics and growth of the autograft as well as freedom from anticoagulation. A 10% reoperation rate, elevated pulmonary homograft gradients, and the surgical complexity remain limiting factors.

Total Autologous Ross Procedure in a Child With Aortic Root Abscess

BACKGROUND AND AIM OF THE STUDY

Endocarditis with aortic root abscess is one of the most complicated surgical problems.

METHODS

An 8-year-old girl presented with dyspnea, high fever, and fatigue. She had stenotic bicuspid aortic valve with endocarditis and aortic root abscess. Ross procedure was performed with fresh autologous pericardial tube and pericardial monocusp valve. Right internal mammary artery to right coronary artery bypass was also done due to destroyed right coronary artery ostium.

RESULTS

Four years after the operation she is in excellent clinical condition without medications. Echocardiography reveals mild autograft regurgitation and mildly stenotic right ventricular outflow tract.

CONCLUSIONS

If homografts are not available, total reconstruction of RVOT with autologous fresh pericardium may offer reasonable early and mid-term results especially when active endocarditis and aortic root abscess is involved.

Valved Bovine Jugular Vein Conduits for Right Ventricular Outflow Tract Reconstruction in Children: An Attractive Alternative to Pulmonary Homograft

BACKGROUND

Pulmonary homografts (PH) have been the preferred valved conduits for right ventricular outflow tract (RVOT) reconstruction in the US since the mid-1980s. Although PHs have worked well for Ross patients, many PH extracardiac conduits used for congenital heart surgery suffer from degeneration and develop regurgitation and obstruction within months after implantation and require replacement within 4 to 6 years. Recently a valve-containing bovine jugular vein (Contegra, Medtronic, Inc, Minneapolis, MN) was introduced for clinical trials for a variety of patients requiring RVOT reconstruction.

METHODS

The early results of RVOT reconstruction utilizing the Contegra conduit were retrospectively analyzed in 62 patients. This series consisted of 9 newborns with truncus arteriosus, 39 patients with failed PHs, 6 with pulmonary atresia and 2 with tetralogy of Fallot with absent pulmonary valve, 2 with transposition of great arteries with ventricular septal defect and pulmonary stenosis, and 4 undergoing a Ross procedure. The patients ages ranged from 2 weeks to 18 years (mean, 7.3 +/- 6.0 years) and weights were from 2 to 83 kg (mean, 28.1 +/- 22.3 kg). The Contegra conduit sizes varied in diameter between 12 and 22 mm (mean, 18.2 +/- 4.1 mm).

RESULTS

There were two early (3%) and four (7%) late deaths and none of them was conduit related. There has been one conduit explantation, and seven patients have required reinterventions to relieve stenosis at or beyond the distal anastomosis of the conduit to pulmonary artery bifurcation (8 of 60; 13%). Six of the 7 patients had balloon dilatation of the branch pulmonary arteries for preexisting stenosis. One patient developed distal anastomotic stenosis that did not yield to balloon angioplasty and she underwent surgical patch arterioplasty of the distal anastomosis. The interval from conduit implantation to reintervention ranged from 3 to 27 months (mean, 11.1 +/- 7.8 months). Of these, three patients required placement of a stent in the left (n = 1) or both branch pulmonary arteries (n = 2). During the short to intermediate follow-up in our series we have not observed, on echocardiography, shrinkage of the Contegra as we and others have reported with PHs.

CONCLUSIONS

The Contegra conduit offers a promising alternative for RVOT reconstruction. Early hemodynamic performance compares favorably with PHs. Clinical advantages are greater availability in sizes from 12 to 22 mm and natural continuity between the valve and conduit that allows proximal infundibular shaping without additional materials. The price of the bovine jugular venous valve is approximately one-half that of many PHs in the US. Short-term freedom from dysfunction is at least as good as PHs. Long-term durability must be determined for this new conduit. The Contegra conduit is currently our conduit of choice for RVOT reconstruction in infants, children, and young adults.

Mitral valve replacement with Ross II technique: initial experience

BACKGROUND

Pulmonary autograft mitral valve replacement (PA-MVR) was introduced clinically by Ross in 1967, but has been rarely utilized in North America and Europe. The aim of this study is to review our early experience with PA-MVR.

METHODS

Since June 2002, 8 patients (7 female and 1 male) between 12 to 46 years of age with outgrown mechanical valves (n = 3) failed MV repair for rheumatic or congenital MV disease (n = 4) and irreparable bileaflet myxoid prolapse (n = 1), underwent PA-MVR. The pulmonary autograft was harvested and replaced using a pulmonary homograft. The autografts were mounted within a woven Dacron graft 6-8 mm greater in diameter than the autograft annulus diameter on a preoperative echocardiogram. The graft's external surface was covered with fresh autologous pericardium.

RESULTS

There were no deaths. Intraoperative echocardiography confirmed a mean MV gradient of 4 mm Hg with trivial (n = 7) or mild (n = 1) regurgitation. Follow-up (range, 13 to 36 months) echocardiography in 4 patients showed no increase in MV gradient or regurgitation. One patient with severe myxoid degeneration and one patient with rheumatic disease, both with systemic hypertension, developed progressive regurgitation due to stretching of a single autograft leaflet producing prolapse. One patient developed a moderate gradient due to retention of excessive native mitral leaflet and subannular chordal tissue. Three of 4 patients have required PA-MVR replacement with mechanical valves 6 to 14 months post-PA-MVR. One asymptomatic patient with mild to moderate mitral regurgitation is being followed after treatment of her systemic hypertension.

CONCLUSIONS

Pulmonary autograft mitral valve replacement offers selected patients a potentially lifelong autologous valve without the need for long-term anticoagulation. The PA-MVR technique deserves careful consideration in younger patients in sinus rhythm. Postoperative systemic hypertension should be treated aggressively to prevent excessive stress on the pulmonary autograft particularly in the early postoperative months.

Homograft valved right ventricle to pulmonary artery conduit as a modification of the Norwood procedure

BACKGROUND

The use of a right ventricle to pulmonary artery (RV-PA) conduit in the Norwood procedure has been proposed to increase postoperative hemodynamic stability. A valve within the conduit should further decrease RV volume load. We report our clinical experience with this modification.

METHODS AND RESULTS

From February 2002 through August 2005, we performed 88 consecutive Norwood procedures using RV-PA conduits. We used composite valved conduits made from cryopreserved homograft and polytetrafluoroethylene (PTFE) in 66 cases (54 pulmonary, 12 aortic homografts), other valved conduits in 14, and unvalved PTFE in 8 cases. Hospital survival was 88.6% overall and increased to 93.1% after the initial year. Early interventions were required in 18 patients (16 for cyanosis). Prestage II cardiac catheterization was performed at a mean age of 126 days. Mean Qp/Qs was 1, with mean aortic saturation 71%, mean O2 extraction 24%, and mean right ventricular end-diastolic pressure 9 mm Hg. Patient weight, use of an aortic homograft valve in the conduit, stage I palliation within the first year of our experience, and low O2 extraction and high transpulmonary gradient prestage II were risk factors for overall death. Early interventions were more frequent in aortic valve conduits compared with all other conduits.

CONCLUSIONS

The valved RV-PA conduit was associated with low early mortality after the Norwood procedure. The majority of these patients had normal cardiac output and well-maintained RV function. There may be a higher risk for early conduit interventions and death when aortic valve homografts are used in the RV-PA conduit.

A Critical Reappraisal of the Ross Operation

Background— The autograft procedure, an option in aortic valve replacement, has undergone technical evolution. A considerable debate about the most favorable surgical technique in the Ross operation is still ongoing. Originally described as a subcoronary implant, the full root replacement technique is now the most commonly used technique to perform the Ross principle.

Methods and Results— Between June of 1994 and June of 2005, the original subcoronary autograft technique was performed in 347 patients. Preoperative, perioperative, and follow-up data were collected and analyzed. Mean patient age at implantation was 44±13 years (range 14 to 71 years; 273 male, 74 female). Bicuspid valve morphology was present in 67%. The underlying valve disease was aortic regurgitation in 111 patients, stenosis in 46 patients, combined lesion in 188 patients, and active endocarditis in 22 patients (in 2 patients without stenosis or regurgitation). Concomitant procedures were performed in 130 patients. Clinical and echocardiographic follow-up visits were obtained annually (mean follow up 3.9±2.7 years, 1324 patient-years; completeness of follow-up 99.4%). The in-hospital mortality rate was 0.6% (n =2), and the late mortality was 1.7% (n=6), with 5 noncardiac deaths (4 cancer, 1 multiorgan failure after noncardiac surgery) and 1 cardiac death (sudden death). At last follow-up, 94% of the surviving patients were in New York Heart Association class I. Ross procedure–related valvular reoperations were necessary in 9 patients: Three received autograft explants, 5 received homograft explants, and 1 received a combined auto- and homograft explant. At last follow-up visit, autograft/homograft regurgitation grade II was present in 5/10 patients and grade III in 4/0. Maximum/mean pressure gradients were 7.4±6.2/3.7±2.1 mm Hg across the autograft and 15.3±9.4/7.6±5.0 mm Hg across the right ventricular outflow tract, respectively. Aortic root dilatation was not observed. Freedom from any valve-related intervention was 95% at 8 years (95% confidence interval 91% to 99%).

Conclusion— Midterm follow-up of autograft procedures according to the original Ross subcoronary approach proves excellent clinical and hemodynamic results, with no considerable reoperation rates. Revival of the original subcoronary Ross operation should be taken into account when considering the best way to install the Ross principle.

Early Graft Failure of Small-Sized Porcine-Valved Conduits in Reconstruction of the Right Ventricular Outflow Tract

BACKGROUND

The quest for an alternative to homografts for reconstruction of the right ventricular outflow tract is ongoing. The Shelhigh No-React (NR-4000PA series) treated porcine pulmonic valve conduit (SPVC) was developed as a potential alternative.

METHODS

During a 12-month period from May 2004 to May 2005, the SPVC was implanted in 34 patients, of whom 62% were younger than 1 year. Median age at operation was 7 months (range, 5 days to 12 years). Thirteen SPCV conduits size 10, 11 size 12, 8 size 14, and 2 size 16 were initially implanted. Since May 2005, however, we have temporarily abandoned its implantation as we were concerned about a number of early failures.

RESULTS

Until November 2005, 1 early and 1 late death have occurred. Both were not conduit related. Fifteen conduits were replaced in 13 patients. Of these, 10 were size 10, 3 size 12, 2 size 14, and none size 16. Mean time to replacement of the SPVC was 313 +/- 116 days. A pseudointimal peel formation and chronic inflammation with foreign-body reaction was found in all explanted conduits at all levels. The maximum of the inflammatory reaction occurred at the valvular level around the porcine tissues, with shrinkage of the valve and hemodynamic compromise. At valvular level, small punctuate calcifications were observed in 2 cases. In 6 patients an acute inflammatory component was observed. At late follow-up (mean follow-up 366 +/- 102 days, 34 patient-years), echocardiography showed a mean graft gradient of 39.8 +/- 29.7 mm Hg, with mild to moderate insufficiency in 4 patients.

CONCLUSIONS

Although the No-React treated valve largely resists calcification, pseudointimal peel formation was found in all explanted conduits and led to multilevel conduit stenoses. The small-sized SPVC can not be regarded as an ideal conduit for right ventricular outflow tract reconstruction.

Ross procedure: medium-term results

INTRODUCTION

The Ross procedure is a safe alternative option for aortic valve replacement in selected patients. Here we present the medium-term results of our experience with this procedure.

METHODS

Between December 1998 and January 2004, 21 patients (16 male, 5 female, mean age 42 years) underwent aortic valve replacement using the Ross operation. Indications for operation were aortic stenosis in 5 patients, aortic regurgitation in 5 patients, aortic stenosis and regurgitation in 9 patients, acute septic endocarditis of a native aortic valve in 1 patient and of a mechanical aortic valve in 1 patient. The root replacement technique was used in 17 patients (81%) and the subcoronary insertion technique in 4 patients (19%).

RESULTS

Hospital mortality was 4.7% (1 patient) and late mortality is zero. Mean follow up duration was 4 years (range 1-6 years). On follow up all of the patients were in New York Heart Association class I. One patient developed neo-aortic root dilatation (5.1 cm) with mild neo-aortic valve regurgitation and underwent a modified David I procedure using a Valsalva graft. None of the patients had a gradient of more than 10 mmHg through the pulmonary autograft. Sixteen patients had no aortic insufficiency, while mild aortic regurgitation developed in three patients. Pulmonary valve regurgitation developed in 11 patients (range 8-75 mmHg) but only one patient (75 mmHg) developed significant asymptomatic stenosis.

CONCLUSIONS

Our experience with the Ross procedure suggests that aortic root replacement with a pulmonary autograft can be performed safely in adult patients. Pulmonary homograft degeneration requiring reintervention might be a rare complication.

Congenital mitral valve surgery: techniques and results

PURPOSE OF REVIEW

Congenital lesions of the mitral valve are rare. Conservative surgery is recognized as the best option. In complex anatomy, however, replacement is the only solution to achieve an acceptable result. This review aims to study the long-term follow-up of classical treatments, conservative or replacement, and to examine new technical advances.

RECENT FINDINGS

The long-term results of conservative surgery are confirmed with a low incidence of reoperation except in mitral valve stenosis. The Ross II operation using a pulmonary autograft is a difficult technique that may be useful in the youngest patient group when prosthetic devices cannot be used.

SUMMARY

In the last few years, surgery of congenital mitral valve lesions has gained from echocardiography, which shows the exact function and anatomy of the mitral valve. The tendency is to avoid multistage operations. Valve replacement by biologic material (Ross II) is still under clinical evaluation.

Ross procedure in infants and toddlers followed into childhood

BACKGROUND

The Ross procedure is commonly used to treat aortic valve disease in pediatric and adult patients. For infants, data are limited regarding survival, reintervention, autograft growth, and function.

METHODS AND RESULTS

The Ross procedure was performed in 27 infants <18 months of age (median age 5.7 months). All patients had congenital aortic stenosis (AS); associated lesions included subAS (n=9), supravalvular AS (n=2), coarctation (n=5), and interrupted aortic arch (n=2). Median follow-up was 6.1 years (range 0.2 to 12.9). There were 3 early deaths and no late deaths. Freedom from reintervention for homograft dysfunction was 87% at 8 years; freedom from autograft reintervention was 100%. Follow-up echocardiograms were available in 17 patients. Estimated peak autograft gradient was 55 mm Hg in one patient and <10 mm Hg in 16. Mild autograft insufficiency was seen in 4 patients; 13 had none. Autograft diameter was measured early postoperatively and at latest follow-up. The mean z score increased from 0.63 to 3.2 (P<0.01) at the annulus and from 0.26 to 2.2 (P<0.01) at the sinus. In a subgroup, the mean autograft z score increased significantly from the postoperative period to 1 year for both the annulus (0.72 to 3.2, P<0.01) and the sinus (0.26 to 2.2, P<0.01), but remained unchanged thereafter.

CONCLUSIONS

The Ross procedure effectively relieves AS in infants. Homograft reintervention occurred in 13% within 8 years. No patient developed significant autograft insufficiency or required autograft reintervention during the follow-up period. Dilatation of the autograft occurred during the first year after surgery and stabilized thereafter.

Is there a possibility for a glutaraldehyde-free porcine heart valve to grow?

OBJECTIVE

A challenging issue is to create a heart valve with growth and remodeling potential, which would be of great interest for congenital heart valve surgery. This study was performed to evaluate the growth and remodeling potentials of a decellularized heart valve.

METHODS

In 4 juvenile sheep (age 12 +/- 1 weeks) with a weight of 24.3 +/- 4.4 kg, a 17-mm diameter decellularized porcine valve was implanted as pulmonary valve replacement. Valve growth was evaluated by transthoracic echocardiography. At explantation, valves were evaluated by gross examination, light microscopy (hematoxylin and eosin, von Kossa, Sirius red, Weigert and Gomori staining), electron microscopy and immunohistochemistry. Atomic absorption spectrometry was performed to evaluate calcium content.

RESULTS

All animals showed fast recovery. The mean follow-up was 9.0 +/- 1.8 months. All sheep at least doubled their weight (54.3 +/- 9.2 kg). Echocardiography showed no regurgitation and a flow velocity of 0.7 +/- 0.1 m/s at the latest follow-up. The valve diameter increased from 17.6 +/- 0.5 to 27.5 +/- 2.1 mm (p < 0.018). Gross examination showed a similar wall thickness of the implanted valve and native pulmonary wall, with smooth and pliable leaflets. Histology showed a monolayer of endothelial cells, fibroblast ingrowth and production of new collagen. No calcification was seen at von Kossa staining, confirmed by low calcium content levels of the valve wall and leaflets at atomic absorption spectrometry.

CONCLUSIONS

This glutaraldehyde-free heart valve showed not only the absence of calcification, but also remodeling and growth potential.

Ross procedure in rheumatic aortic valve disease☆

OBJECTIVE

To assess the results of aortic valve replacement with the pulmonary autograft in patients with rheumatic heart disease.

METHODS

From October 1993 through September 2003, 81 rheumatic patients with aortic valve disease, mean age 29.5+/-11.9 years (11-56 years) underwent, the Ross procedure with root replacement technique. Forty patients were 30 years of age or below (young rheumatics). Associated procedures included mitral valve repair (n=19), open mitral commissurotomy (n=15), tricuspid valve repair (n=2), and homograft mitral valve replacement (n=2).

RESULTS

Early mortality was 7.4% (six patients). Mean follow-up was 92.3+/-40.9 months (7-132 months, median 109 months). Sixty of the 73 patients whose follow-up was available (82%) had no significant aortic regurgitation. Re-operation was required in seven (8.4%) patients for autograft dysfunction with failed mitral valve repair (n=3), autograft dysfunction alone (n=2) and failed mitral valve repair alone (n=2). No re-operations were required for the pulmonary homograft. There were six (7.5%) late deaths. Actuarial survival and re-operation-free survival at 109 months were 84.5+/-4.1% and 90.5+/-3.7%, respectively. Freedom from significant aortic stenosis or regurgitation was 78.4+/-5.2% and event-free survival was 64.6+/-5.8%. When compared to rheumatics above 30 years of age, the relative risk of autograft dysfunction was high in the young rheumatics.

CONCLUSION

The Ross procedure is not suitable for young patients with rheumatic heart disease. However, it provides acceptable mid-term results in carefully selected older (>30 years) patients with isolated rheumatic aortic valve disease.

The Ross Procedure: New Insights Into the Surgical Anatomy

BACKGROUND

The precise knowledge of regional anatomical details is of utmost importance specially in complex procedures such as the Ross operation. This anatomical study offers a critical approach regarding the advantages, limits, and precautions for this procedure.

METHODS

Using dissection techniques, magnifications up to x6 and nontraditional approaches, 68 fixed normal heart specimens were studied over a 2-year period. The details of surgical relevance such as the boundaries and relations of the pulmonary and aortic roots, their vascularization, and the number and distribution of the septal arteries are described.

RESULTS

The aortic and pulmonary roots include interdependent elements functioning in a coordinated manner and establishing important relations with adjacent structures. Both coronary arteries vascularize the arterial roots. The infundibular branches from the right coronary artery are larger and more constant. The septal arteries establish important relations with the pulmonary infundibulum but their contribution to its vascularization is negligible. In this series, the main septal artery was the second, showing the longest retroinfundibular course. However, no constant relation was found between this vessel and the intraventricular landmarks.

CONCLUSIONS

A novel approach was used by performing nontraditional dissections of the arterial roots and by studying their vascularization The depicted details are useful to the surgeon specializing in the Ross procedure and represent the basis for further research.

The occurrence of postoperative pulmonary homograft stenosis in adult patients undergoing the Ross procedure

BACKGROUND AND AIM OF THE STUDY

The Ross procedure employs an autologous pulmonary valve to replace the aortic valve, but requires pulmonary homograft replacement. Concerns regarding long-term homograft function may limit the adoption of this technique. Herein, the incidence of, and factors leading to, stenosis of the homograft were examined.

METHODS

Data were collected from 131 patients (32 females, 99 males) who underwent a Ross procedure between July 1994 and December 2003. Complete follow up data were collected from 113 of 125 (90.4%) living patients. Donor valve information, including storage time, was supplied by the graft manufacturers. Data were analyzed using chi-square tests, t-test and logistic regression.

RESULTS

The mean patient follow up was 703 +/- 574 days (median 599 days; range: 2 to 2,408 days). Echocardiographic stenosis had occurred in 14 patients (12.4%). Four patients (3.2%) required homograft replacement, and two required balloon valvuloplasty. There was no significant difference in graft vendor, recipient, donor age or blood type match between stenotic and non-stenotic recipients. Donor valve size was appropriate for the recipients, and greater than predicted by recipient body surface area (BSA). Donor valves that developed stenosis had a shorter storage time after processing (160 +/- 100 versus 249 +/- 223 days; p = 0.03). Male donor valves became stenotic in 9.9% (7/71) of male recipients, but in none of 20 females. Female donor valves became stenotic in 27.3% (3/11) of male recipients, and in 28.6% (2/7) females. Logistic regression showed donor gender to be a significant predictor for stenosis (p = 0.007; odds ratio 14.1 for female/male donors; 95% CI 2.1-96.4).

CONCLUSION

Donor valves which developed stenosis had a shorter mean cryopreservation time than those that did not develop stenosis. In addition, female donor homografts appeared to develop stenosis at a greater rate, independent of patient age, graft size to BSA match, and blood type.

Do pulmonary autografts provide better outcomes than mechanical valves? A prospective randomized trial

BACKGROUND

The objective of this study was to compare the performance of pulmonary autografts with mechanical aortic valves, in the treatment of aortic valve stenosis.

METHODS

Forty patients with aortic valve stenoses, and below the age of 55 years, were randomly assigned to receive either pulmonary autografts (n = 20) or mechanical valve (Edwards MIRA; Edwards Lifesciences, Irvine, CA) prostheses (n = 20). Clinical outcomes, left ventricular mass regression, effective orifice area, ejection fraction, and mean gradients were evaluated at discharge, 6 months, and one year after surgery. Follow-up was complete for all patients.

RESULTS

Hemodynamic performance was significantly better in the Ross group (mean gradient 2.6 mm Hg vs 10.9 mm Hg, p = 0.0005). Overall, a significant decrease in left ventricular mass was found one year postoperatively. However, there was no significant difference in the rate and extent of regression between the groups. There was one stroke in the Ross group and one major bleeding complication in the mechanical valve group. Both patients recovered fully.

CONCLUSIONS

In our randomized cohort of young patients with aortic valve stenoses, the Ross procedure was superior to the mechanical prostheses with regard to hemodynamic performance. However, this did not result in an accelerated left ventricular mass regression. Clinical advantages like reduced valve-related complications and lesser myocardial strain will have to be proven in the long term.

Ross-Konno procedure and ostial plasty in a child with homozygous hypercholesterolemia: case report

Although the Ross procedure is preferred for aortic valve replacement in young and female patients, there are no reported cases of hypercholesterolemic aortic pathology due to homozygous familial hypercholesterolemia. Long-term durability of the pulmonary autograft in patients with postoperative high blood cholesterol levels is of interest. A 14-year-old girl with homozygous familial hypercholesterolemia who underwent the Ross-Konno procedure and left coronary artery ostial plasty was followed for 57 months, with pulmonary autograft function, coronary arteries and lipid profile being monitored. There were no signs of narrowing, insufficiency or calcification of the pulmonary autograft; neither was there any narrowing in the left main coronary ostium. The patient's total cholesterol level was reduced from 897 to 262 mg/dl by use of anti-lipidemic medication and weekly lipid apheresis. Follow up data suggest that a pulmonary autograft may be preferable in children with hypercholesterolemic aortic valvular pathology, as well as in children with aortic valvular diseases of other etiologies.

Pediatric Autograft Aortic Root Replacement: A Prospective Follow-Up Study

BACKGROUND

The autograft procedure offers children who require aortic valve replacement the advantage of an autologous valve that has growth potential and does not require anticoagulation. However, the autograft procedure is a double valve operation and its durability depends on the lifetime of both the autograft and the pulmonary valve substitute. We present our clinical experience with pediatric autograft aortic root replacement.

METHODS

Between September 1988 and September 2003, 47 children (mean age, 8 years; standard deviation, 5 years; range, 3 months to 15 years) underwent autograft aortic root replacement. Perioperative characteristics and annual follow-up information were collected prospectively.

RESULTS

The male to female ratio was 32 to 15. Eighty-nine percent of patients had congenital aortic valve disease, 47% of patients previously underwent cardiac surgery, and 43% had an aortic valve balloon dilatation. Concomitant left ventricular outflow tract enlargement was performed in 19 patients. In all cases the pulmonary valve was replaced using an allograft. There were no hospital deaths. Mean follow-up was 6.1 years (median 5.4; range, 1 month to 15 years; total of 284 patient years). During follow-up 3 patients died. Cumulative survival was 95% at 1 year and 93% at 12 years. One patient had endocarditis of the pulmonary allograft develop. Three patients required reoperation; two patients for allograft degeneration at 9.4 and 12.8 years, and 1 for combined autograft dilatation and allograft degeneration at 7.7 years postoperatively. Freedom from valve-related reoperation was 86% at 12 years.

CONCLUSIONS

Pediatric autograft aortic root replacement is associated with acceptable mortality and reoperation rates in the first decade postoperatively. It allows most children to grow into adulthood without the need for anticoagulation and additional valve replacements.

An inverted left atrial appendage mimicking an intraatrial thrombus after a ross operation

Inverted left atrial appendage (ILAA) is a rare manifestation. The case is reported of a patient with a history of factor V Leiden who underwent a Ross operation. An intra-atrial mass was discovered one month postoperatively and suspected to be a thrombus. Despite six months' anticoagulant treatment, the intra-atrial mass persisted. Ultimately, the patient was reoperated on due to hemostatic risks factors, and an ILAA was found. The diagnosis of ILAA remains a major challenge. Despite widespread use of postoperative echocardiography, the few reported cases confirm ILAA to be a rare phenomenon. The finding at post-cardiotomy echocardiography of a left atrial mass associated with an absence of the left appendage is highly suggestive of a diagnosis of ILAA. As the incidence of complications remains to be defined, treatment remains controversial, but embolic risk factors such as hemostatic disease or atrial fibrillation invariably lead to surgery. In an asymptomatic patient without thromboembolic risks factors, a conservative approach should be considered, because of the risk of reoperation.

Reoperations for aortic aneurysm after the Ross procedure

BACKGROUND AND AIM OF THE STUDY

Among late complications after the Ross operation, autograft dilatation is likely the most common. In order to define prevalence, consequences and management of autograft dilatation, a 10-year clinical experience was reviewed.

METHODS

A total of 112 patients (mean age 29 +/- 10 years) underwent cross-sectional echocardiographic follow up. End-points of the study were freedom from autograft dilatation (diameter >4 cm, indexed as 0.21 cm/m2) and from reoperation for dilatation. Risk factors for autograft dilatation were also identified.

RESULTS

There were 110 late survivors; average follow up was 5.1 +/- 1.9 years (range: 0.3 to 10.6 years). At 10 years, autograft dilatation was identified in 32 patients (29%), compatible with aortic aneurysm (>5.0 cm) in seven patients (6%). Seven of 32 patients (22%) presented moderate or greater autograft insufficiency. Ten-year freedom from dilatation was 43 +/- 8%, and from regurgitation was 75 +/- 8%. At multivariate analysis, preoperative aneurysm (p = 0.02), root replacement technique (p = 0.03) and absence of root buttressing (p = 0.04) were predictive of dilatation. Reoperation for autograft aneurysm was performed in five patients at a mean of 7.3 +/- 0.8 years after the Ross procedure, while two patients await reintervention. Two patients had root replacement and three remodeling with valve preservation (two root replacements, one sinotubular junction replacement): all survived reoperation. Ten-year freedom from root reoperation was 81 +/- 6%, and from full root replacement was 94 +/- 2%.

CONCLUSION

With increasing follow up after the Ross operation, the incidences of root dilatation and reoperation are likely to rise. Graft replacement of coexisting aneurysm, avoidance of root replacement technique and the use of root-stabilization measures may reduce the prevalence of late root pathology. Early replacement of dilated autograft roots may allow preservation of the autologous pulmonary valve.

Modification to the Ross procedure to prevent autograft dilatation

Dilatation of the pulmonary autograft is a problem described following Ross procedure for aortic valve replacement. Patients at risk seem to be those with aortic insufficiency, bicuspid aortic valves, and those with aneurismal ascending aortas. We describe a technique for encasing the pulmonary autograft in a Dacron tube to prevent dilatation in these patients. This technique is reproducible and includes sewing the coronary arteries to all layers of the autograft and Dacron construct. Short-term follow-up shows excellent outcomes with respect to autograft valve function and lack of annular or sinotubular dilatation. This procedure may be useful for extending the Ross procedure to young adults, where autograft growth is no longer needed, to provide a non-dilatable neoaortic root.

Ross procedure for aortic insufficiency due to doubly committed subarterial ventricular septal defect in adults

A 52-year-old female, with aortic insufficiency due to doubly committed subarterial ventricular septal defect (VSD) underwent a successful surgical repair by the Ross procedure. Preoperatively, she developed congestive heart failure because of less compliance to oral medication, raising concerns regarding life-threatening thromboembolism if she undergoes mechanical valve replacement. Despite the pulmonary autograft being defective, there were no difficulties in completing the surgery. The defect of pulmonary autograft and the VSD was closed by an expanded polytetrafluoroethylene patch. She tolerated the procedure well and now enjoys improved quality of life. We present a discussion of the indication of Ross procedure in the rare presentation of congenital heart disease, as well as several issues raised in this case.

Ross Procedure and Left Ventricular Mass Regression

Background— Return of left ventricular mass to normal is considered to be a favorable result of aortic valve replacement. The Ross procedure provides near normal hemodynamics and thus allows studies of left ventricular (LV) reverse remodeling. LV mass regression may be influenced by surgical technique (subcoronary [SC] versus root replacement [RR]).

Methods and Results— Data from the German Ross Registry were analyzed. A total of 646 patients (mean age: 43.6±12.7 years, range: 16 to 71 years; SC technique n=295, RR technique n=351) underwent a Ross procedure in 7 participating centers from 1990 to 2004. The patients underwent preoperative and postoperative echocardiographic evaluations. Mean follow-up time was 3.5±2.5 years (range 0.12 to 13.7 years). Follow-up completeness was 97%. The LV mass index (LVMI) decreased significantly during follow-up in both groups (SC: 209±53 preoperatively to 154±48 at 1-year follow-up, [ P <0.01 versus preoperative values] to 149±51g/m 2 at 2-year follow-up, [ P =NS 1-year versus 2-year follow-up] versus RR: from 195±56 preoperatively to 144±51 at 1-year follow-up [ P <0.01 versus preoperative values] to 140±49g/m 2 [ P =NS 1-year versus 2-year follow-up]). LVMI regression remained stagnant 1 year after the Ross procedure in most patients in both groups. On the basis of multivariate analysis, predictors for incomplete LVMI regression after the autograft procedure were high preoperative LVMI, smoking, and uncontrolled diastolic hypertension.

Conclusions— At mid-term echocardiographic follow-up, patients of both groups had favorable autograft hemodynamics. Risk factors for incomplete postoperative LVMI regression in our study were smoking and persistent diastolic hypertension. This emphasizes the importance of cessation of smoking and treatment of arterial hypertension, even in younger patients, after corrected aortic valve disease.

Aortic Valve Replacement With the Pulmonary Autograft: Mid-Term Results

BACKGROUND

The purpose of this study is to assess the mid-term results of aortic valve replacement with the pulmonary autograft.

METHODS

From October 1993 through September 2003, 153 patients with aortic valve disease (81 rheumatic and 72 non-rheumatic), with a mean age of 28 +/- 14.2 years underwent the Ross procedure with root replacement technique and right ventricular outflow tract reconstruction using a homograft. Associated procedures included mitral valve repair (n = 19), open mitral commissurotomy (n = 15), tricuspid valve repair (n = 2), homograft mitral valve replacement (n = 2), and subaortic membrane resection (n = 1).

RESULTS

Early mortality was 6.5% (10 patients). Mean follow-up was 77 +/- 42 months (range, 7 to 132 months; median, 90 months). One hundred, twenty-one survivors (84.6%) had no significant aortic regurgitation. Reoperation was required in 10 patients for autograft dysfunction alone (n = 3), infective endocarditis (n = 2), autograft dysfunction with failed mitral valve repair (n = 3), and failed mitral valve repair alone (n = 2). No reoperations were required for the pulmonary homograft. There were 8 late deaths. Actuarial and reoperation-free survival at 90 months were 91.% +/- 3.5%, 95.3% +/- 2.7%, in non-rheumatics and 86.1 +/- 3.9%, 90.5 +/- 3.7% in rheumatics, respectively. Freedom from significant aortic stenosis or regurgitation was 91.5 +/- 2.8% in non-rheumatics and 80.6 +/- 4.8% in rheumatics. Event-free survival was 86.2 +/- 4.9% in non-rheumatics and only 68.9 +/- 5.3% in rheumatics.

CONCLUSIONS

The Ross procedure is not recommended for young patients (< 30 years) with rheumatic heart disease. It provides satisfactory hemodynamic and clinical results in properly selected patients. Important autograft dilatation was not observed in our patients.

[The determination of trace amounts of protein in solutions containing surface-active substances]

A rapid and sensitive method for protein determination (0.5-16 micrograms) in samples of any volume containing various surfactants in concentration up to 1% is suggested. The method includes the protein acid denaturation, the solution of acid insoluble precipitate of detergent in ethanol (25-30%), the protein determination on nitrocellulose filter, dyeing by aminoblack 10 B, elution of dyed complex and colorimetric determination at 630 nm.

Immunological and echocardiographic evaluation of decellularized versus cryopreserved allografts during the Ross operation

OBJECTIVE

Compare the immunological and echocardiographic data of decellularized versus cryopreserved allografts used for RVOT reconstruction during Ross operation.

METHODS

From 16/01/03 thru 07/10/03, 20 Ross operations were performed using decellularized (n=11) or cryopreserved (n=9) allografts. Echocardiography was done at discharge, 1, 3, 6 and 12 months and annually thereafter. Samples for determination of antibodies against HLA class I and II were obtained preoperatively and at days 5, 10, 30, 90 and 180 postoperatively. These samples were tested by the ELISA method in LAT-M dishes (unspecific) for identification of circulating antibodies and the results expressed as mean sample values (Is=DO/cutoff). If positive, LAT-E (specific) was performed and PRA levels determined.

RESULTS

There was no mortality. Cryopreserved allografts showed marked Is values elevations for class I and II antibodies which started at the first month and remained elevated up to 6 months. In contrast, of the patients receiving decellularized allografts, seven remained negative, two patients had only marginal elevation of class I antibodies and two patients showed abnormal elevations of PRA levels. This response happened earlier than in the cryopreserved group, starting on the 5th postoperative day and has returned to baseline levels in one case. Echocardiography showed mild, but significant, elevation of gradients in cryopreserved valves but none in the decellularized.

CONCLUSIONS

Decellularized allografts had normal function up to 18 months and showed important reduction of the immunogenic response when compared to cryopreserved valves.

Factors influencing late allograft valve failure

Allograft valves are a valuable valve replacement substitute in the surgical management of heart valve disease. It remains the valve substitute of choice in the reconstruction of the right ventricular outflow tract in children with congenital heart disease and in the Ross procedure. However, its durability remains suboptimal, particularly in children. This article reviews the mechanisms and factors implicated in late allograft dysfunction, with a focus on the evidence for an immunological cause for allograft valve failure. Unravelling the mechanisms of allograft valve failure may allow modification of the allograft to improve its long-term durability.

Optimal Size of a Monocusp Patch for Reconstruction of a Hypoplastic Pulmonary Root: An Experimental Study in Pigs

BACKGROUND

Transannular patching is often performed to relieve congenital pulmonary stenosis, especially in tetralogy of Fallot. Theoretically, a monocusp patch can reduce patch-related pulmonary regurgitation, but the optimal size relation between the implant and the native hypoplastic pulmonary root is not well defined.

METHODS

In 11 pigs, peak pressure gradient and regurgitation fraction across the pulmonary root were measured. During cardiopulmonary bypass, two cusps including the pulmonary artery wall were resected and the midpoint of the free margin of the remaining cusp was sutured to the sinus wall to imitate a hypoplastic pulmonary root. Transannular patching was performed using a noncoronary segment of a porcine aortic root. After discontinuation of cardiopulmonary bypass, all measurements were repeated. Thereafter, the cusp of the patch was resected, and all measurements again repeated. Anatomic dimensions were determined after the pigs had been sacrificed.

RESULTS

Regurgitation fraction increased from 0.2% +/- 3.4% at baseline to 15.5% +/- 6.2% after reconstruction with a monocusp patch and to 60.0 +/- 18.6% after the cusp of the monocusp patch had been resected (p < 0.001). The median peak pressure gradient increased from 0 to 1 to 6 mm Hg (p = 0.013), respectively. The regurgitation fraction negatively correlated with the ratio of the length of the monocusp patch to that of the hypoplastic pulmonary root (r = -0.63, p = 0.037).

CONCLUSIONS

A monocusp patch for reconstruction of a hypoplastic pulmonary root results in significantly less regurgitation than a nonvalved patch of the same size, while the peak pressure gradient remains normal. The lowest regurgitation fraction was observed with a monocusp patch two-times the length of the circumference of the hypoplastic pulmonary root.

Pulmonary Autograft for Mitral Valve Replacement in Infants: The Ross-Kabbani Operation

We describe the cases of 2 infants aged 6 and 2 1/2 months, respectively, affected by mitral valve dysplasia that caused severe valvular insufficiency and heart failure in which a surgical correction was indicated because of critical general conditions. In both patients the anatomic characteristics of the valves were not suitable for repair, and an implant of a mechanical prosthesis was excluded because of the very young age of the infants and the impossibility of maintaining an adequate anticoagulant therapy. Therefore a Ross-Kabbani intervention was performed with an implant of a pulmonary autograft (in the mitral position) and an insertion of a pulmonary homograft. The postoperative course was free of major complications and good function of the autograft was present at short-term follow-up in both cases.

Mid-term findings on echocardiography and computed tomography after RVOT-reconstruction: comparison of decellularized (SynerGraft) and conventional allografts

OBJECTIVE

The immune response against human-leucocyte-antigens on donor-cells may be an important factor contributing to the degeneration of allograft-valves. We have previously reported that the use of the decellularized allograft SynerGraft (CryoLife) reduces the immunologic response of the allograft-recipient. In this study we compare the echocardiographic and computed tomography angiographic (CTA) findings of SynerGrafts with conventional cryopreserved allografts.

METHODS

22 patients who received a pulmonary SynerGraft (SG-group) (21 during a Ross-procedure) underwent CTA and resting echocardiography (median: 10 months postoperatively). 47 randomly chosen patients who underwent a Ross-procedure served as controls (C-group) (median: 32 months postoperatively).

RESULTS

Neither the pressure gradients (mean: SG=9+/-4 vs C=10+/-4mmHg; P=0.64) across the allograft, nor the effective orifice area (EOAI) (SG=0.93+/-0.80 vs C=0.93+/-0.42cm(2)/m(2); P=0.96) differed between the groups. The EOAI showed a significant correlation with the smallest allograft-conduit-area measured on CTA (r=0.81; P<0.001) which was most frequently (n=34) found in the proximal postvalvular tubular part of the conduit. Calcifications (n=11) or a fibroproliferative reaction (n=15) were rarely observed. Overall, there were no radiologic differences between the groups. On CTA, the smallest diameter of the allograft-conduits was significantly smaller than the diameter given on the cryopreservation protocol (SG=16+/-3 and C=17+/-3mm vs 25mm in both groups; P<0.001 each) whereas the diameter of the distal part of the allograft was not (SG=24+/-2, P=0.066, and C=25+/-3mm, P=0.82).

CONCLUSIONS

Despite a significant shorter follow-up in the SynerGraft-group, no functional or radiologic differences were observed as compared to control-patients. The smallest diameter is located almost exclusively at the proximal level of allograft-conduits.

Oversizing pulmonary homograft conduits does not significantly decrease allograft failure in children

OBJECTIVE

Placement of oversized pulmonary ventricle-pulmonary artery conduits is routinely performed to decrease conduit failure in children. However, this practice has recently been challenged as somatic outgrowth may not be the main determinant of allograft failure in children. Our objective was to determine whether placement of oversized homografts for extracardiac pulmonary ventricle (PV) outflow tract reconstruction improves longevity in young children.

METHODS

We reviewed 102 consecutive PV-PA conduits inserted in 70 patients less than 18 years between 1984 and 2003. Conduits placed in an anatomic position (n=23) as part of a Ross operation, were excluded. Conduits were initially stratified into two age groups: Group 1, those placed in patients <or=10 years, and Group 2, those placed in patients >10 years. Normalization of conduit size to patient's body surface area at the time of insertion (z-value) was then performed to divide the conduits into oversized (O/S) and non-oversized (NO/S) groups. Determinants of conduit failure and allograft longevity were then compared between groups.

RESULTS

Seventy-nine extracardiac conduits were placed, and 57 of these were in patients under 10 years of age. The majority had a diagnosis of tetralogy of Fallot (n=38), truncus arteriosus (n=19), pulmonary atresia with ventricular septal defect (n=12), or D-TGA with pulmonary stenosis and ventricular septal defect (n=7). Thirty-seven conduits were oversized (O/S) based on z-value, and 42 were non-oversized (NO/S), and the mean age at initial homograft placement was 7.0+/-7.5 years. Overall, oversizing conferred no significant advantage with respect to actuarial freedom from homograft replacement at 1, 5, or 10 years (96, 79, and 21%, O/S vs 93, 60, and 24%, NO/S), P=0.44. Oversizing was more frequent in Group 1 than Group 2 (53 vs 32%), and conduit failure was also more frequent with 49% requiring reoperation during the study period vs 38% in Group 2. In the subset of patients <or=10 years, both homograft explantation rate (50% O/S vs 48% NO/S) and median interval to conduit failure were similar between the O/S and NO/S patients (7.1 vs 4.8 years), P=0.340. Risk factors for conduit failure identified in multivariable regression analysis included the presence of pulmonary artery branch stenosis, lack of previous definitive repair, a diagnosis of pulmonary atresia, the need for percutaneous intervention.

CONCLUSIONS

There is no significant benefit to placement of an oversized PV-PA homograft in this series of patients from a single institution. Even in young patients with rapid somatic growth, normalizing extracardiac allografts to BSA provides excellent conduit longevity and outcomes.

[Aortic valve operation in young adults]

Young adults who have to undergo aortic valve surgery will frequently have (relative) contraindications to oral anticoagulation therapy because either pregnancy is planned or their life-style is very active. This review focuses on the surgical options available and assesses the literature focusing on the experience with each option obtained in young adults. There are no randomized studies in this age group which compare mechanical aortic valve replacement with any alternative option with regard to survival, need for reoperation, or quality of life. Among the alternative techniques, the Ross-procedure (pulmonary autograft) and aortic valve repair are of special interest. With the Ross-procedure, there is a rather large experience in young adults, and the results up to 10 years postoperatively are excellent. Unfortunately, there is only limited experience with this technique beyond that time.

Pericardial sewing-cuff: an alternative surgical technique for full-root implantation of aortic allograft and pulmonary autograft

The following is a description of a modified technique for the reinforcement of proximal anastomosis regarding the process of aortic allograft or pulmonary autograft full root implantation. A double width pericardial strip is used to create a pericardial sewing-cuff to be used as a neo-ring. This technique is said to be best suited for decreasing the operative bleeding, reducing anastomotic pitfalls and concomitant repair of the aortic annulus.

Neoaortic Aneurysm After Stage I Norwood Reconstruction

Treatment of hypoplastic left heart syndrome through staged repairs has resulted in patients surviving into adulthood. Use of either aortic or pulmonary homografts in performing the neoaortic reconstruction has become the standard of practice with relatively few problems. We report the case of an asymptomatic adolescent boy who had an enlarging neoaortic aneurysm and mild neoaortic regurgitation develop after undergoing a stage I Norwood procedure using a pulmonary homograft. Given the risk for rupture and a concern for further functional deterioration of the neoaortic valve, the patient underwent repair. Histologic examination showed a striking accumulation of myxoid material as well as abnormal vasculature in both the native and engrafted portions of the neoaorta.

Prospective evaluation of aortic valve replacement in young adults and middle-aged patients: mechanical prosthesis versus pulmonary autograft

BACKGROUND AND AIM OF THE STUDY

The best option for aortic valve replacement (AVR) in young adults and middle-aged patients remains controversial. A longitudinal comparison between the Ross procedure (RP) and mechanical prosthesis (MP) was conducted in this group of patients.

METHODS

Between January 1997 and January 2003, 125 consecutive patients (age range: 20-50 years) were submitted for AVR; 62 patients (mean age 37.73+/-7.28 years) were included in the MP group, and 63 (mean age 35.33+/-7.63 years) in the RP group. Gender, etiology, NYHA functional class and other preoperative data were comparable between the two groups.

RESULTS

The operative mortality was four (6.5%) in the MP group, and one (1.6%) in the RP group (p = NS). The postoperative complication rate was similar in both groups. Two RO patients required early autograft replacement due to severe regurgitation. There were no late deaths during the follow up period. In the MP group, three patients (4.8%) suffered major bleeding, three (4.8%) were diagnosed with prosthetic endocarditis (one required reoperation), and three (4.8%) suffered valve- or coumarin-related thromboembolic complications. All RP patients were free from bleeding, thromboembolic, or infectious complications, but three suffered severe pulmonary homograft stenosis (one re-replacement, one Palmaz stent, and one under clinical surveillance). The combined freedom from death or major complications was 64.72+/-4.3% in the MP group, and 87.92+/-9.65% in the RP group (p = 0.068).

CONCLUSION

Intraoperative and early postoperative morbidity and mortality rates were similar among RP and MP patients, despite a steep learning curve during the early RP cases. Although the follow up was limited, and homograft-related morbidity was seen in the RP group, the overall five-year major complication rate supported use of the pulmonary autograft for AVR in patients aged between 20 and 50 years.

The Ross Operation: An Evaluation of a Single Institution's Experience

BACKGROUND

Pulmonary autograft aortic root replacement was used in adults. Risk factors for aortic valve incompetence (AI) and pulmonary homograft valve stenosis are identified.

METHODS

From February 1991 through May 2003, 103 patients, with a mean age of 35.2 +/- 9.5 years, underwent aortic root replacement with the pulmonary autograft. Annulus reinforcement (reduction annuloplasty or use of root ring) was carried out in 45 patients. In all but 1 patient, the right ventricular outflow tract was reconstructed with a cryopreserved pulmonary homograft. Mean follow-up duration was 6.0 +/- 2.8 years (range 0.3 to 11 years).

RESULTS

There were no hospital deaths. Overall patient survival was 98.9 +/- 1.0% at 1 year and 97.3 +/- 1.9% at 10 years. Autograft function follow-up resulted in 5 patients requiring reoperation for aortic incompetence. The univariate risk factors for aortic incompetence at discharge and during follow-up were respectively annulus reinforcement (p = 0.05) and bicuspic aortic valve (p = 0.05). Reoperation for homograft failure occurred in 1 patient. During follow-up, 24 patients (25.5%) developed homograft stenosis (gradient > 20 mm Hg). Univariate analysis indicated the diameter of the homograft (p = 0.001) as factor associated with stenosis during follow-up. Cox regression identified smaller diameter of the homograft (p = 0.001) and older age of donor (p = 0.002) as independent risk factor for the development of homograft stenosis.

CONCLUSIONS

The Ross operation can be performed with few complications. Although both the aortic autograft and the pulmonary homograft have limited durability, this has not yet resulted in considerable reoperation rates and associated morbidity and mortality.

[Replacement of the aortic valve with pulmonary autograft (the Ross procedure)]

The search for the ideal substitute for the aortic valve led Donald Ross to develop the pulmonary autograft concept in 1967. A historical, technical, an scientific review of this surgical option is presented together with our clinical experience.

MATERIALS AND METHODS

The literature is reviewed to identify the advantages and pitfalls of the Ross procedure over the last decades. We also present our clinical experience with 100 patients operated between 1997 and December 2003.

RESULTS

Of the total, 70% (n = 70) were males, mean age was 29.32 +/- 11.9 years, with 20 patients under 16 and 6 patients under 10 years. Twenty-five patients (25%) had 31 previous interventions. There were 41 associated procedures in 34 patients. Perioperative mortality was 2% (two patients). Eight patients required reexploration for bleeding, one required an aortocoronary bypass, an one a permanent pacemaker. Follow-up was 97% with 2.71 patients/year (average 32.55 +/- 19.01 months). Two patients required Autograft replacement, one suffered a 44-mm dilatation of the Autograft, and one 13-year-old girl developed Autograft endocarditis. Six patients suffered severe Homograft stenosis (> 50 mm/Hg), two were treated percutaneously, and one required replacement. Combined freedom from reintervention is 93.56 +/- 2.81% at 5 years.

CONCLUSIONS

The Ross procedure is a mature concept with thousands of patients operated worldwide and a cumulative experience of over 30 years. Although we believe that it is the procedure of choice in the pediatric population, women in child-bearing age, and substantial subgroups of adult patients, efforts must continue to minimize the incidence of auto- and Homograft failure in the long-term.

The Ross procedure is not the procedure of choice for the teenager requiring aortic valve replacement

The Ross procedure was a remarkable technical achievement when it was introduced in 1967. Although the long-term results for the procedure when performed in adults using the technique of intra-aortic subcoronary freehand implantation have been satisfactory, the results for children using the technique of complete aortic root replacement have been less satisfactory. Not only have early outgrowth, calcification, and shrinkage of the pulmonary homograft used to reconstruct the right ventricular outflow tract been a problem but in addition some children have experienced excessive dilation of the neoaortic root as well as neoaortic valve regurgitation. In contrast to the Ross procedure, aortic valve repair and other forms of aortic valve replacement do not exclude the possibility of reoperation in the future using more advanced options such as tissue engineered leaflets or valves. Until more information is available regarding long-term performance of the pulmonary root when implanted as a neoaortic root, as well as improved results for reconstruction of the right ventricular outflow tract, the Ross procedure should be used rarely.

The Ross procedure is an ideal aortic valve replacement operation for the teen patient

The Ross procedure is an ideal aortic valve replacement for the teenage patient because the pulmonary autograft is durable, is nonthrombogenic, has excellent hemodynamics, and grows. Since 1992, our center has performed 194 Ross procedures, and 53 of these were in teenagers (10 to 21 years of age). In this group, there have been no perioperative deaths, hospital length of stay was 4 days, and re-operation for autograft failure was only 2% at mean follow-up of 69 months. All patients are in NYHA heart failure class I. Because of its proven efficacy, the Ross operation is our preferred aortic valve replacement for the teenage patient.