Bartonella henselae endocarditis of percutaneously implanted pulmonary valve: a case report

Percutaneous pulmonary valve implantation (PPVI) has revolutionized the management of right ventricular outflow tract dysfunction after repaired congenital heart disease. The technology is considered to be safe, with a relatively low complication rate. Infection is one of the described complications of PPVI, and to date five cases of culture-positive infective endocarditis of percutaneously implanted pulmonary valve have been reported worldwide. Herein is reported the first ever case of culture-negative endocarditis of a percutaneously implanted pulmonary valve, caused by Bartonella henselae, five years after implantation in a 15-year-old patient with a repaired truncus arteriosus.

Late aortic dilatation and regurgitation after Ross operation

The Ross operation, a procedure of replacement of the diseased aortic valve with an autologous pulmonary valve, has many advantages such as no need for anticoagulation therapy and similar valve function and growth potential as native valves. However secondary aortic disease has emerged as a significant complication and indication for reoperation. We report a 48-year-old woman who had Ross operation in 1997 for a damaged bicuspid aortic valve and severe aortic regurgitation due to subacute bacterial endocarditis complicated by aortic root abscess. In 2009, 12 years later, progressive severe aortic regurgitation with incomplete coaptation and mild dilatation of the aortic root was shown on echocardiography and contrasted CT, while the pulmonary homograft retained normal function. She subsequently underwent aortic valve replacement. Histopathological examination of the explanted neo-aortic valve and neo-arterial wall revealed pannus formation at the nodulus Arantii area of the three valve cusps, ventricularis, and arterialis. The amount of elastic fibres in the neo-aorta media was less than usual for an aorta of this patient's age but was similar to a pulmonary artery. The pathological findings were not different from other studies of specimens removed between 7 to 12 years after Ross operation. However, the pathophysiology and long-term implications of these findings remain debatable. Considering the anatomical and physiological changes induced by the procedure, separate mechanisms for aortic dilatation and regurgitation are worthy of consideration.

Long-term outcomes after autograft versus homograft aortic root replacement in adults with aortic valve disease: a randomised controlled trial

BACKGROUND

The ideal substitute for aortic valve replacement in patients with aortic valve disease is not known. Our hypothesis was that the regulatory and adaptive properties of a living valve substitute could improve the long-term outcomes in patients. We therefore compared these outcomes after autograft aortic root replacement (Ross procedure) versus homograft aortic root replacement in adults.

METHODS

Male and female patients (<69 years) requiring aortic valve surgery were randomly assigned in a one-to-one ratio to receive an autograft or a homograft aortic root replacement in one centre in the UK. The random allocation sequence was computer generated. Treatment was not masked. The primary endpoint was survival of patients at 10 years after surgery. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN03530985.

FINDINGS

228 patients were randomly assigned to receive an autograft or a homograft aortic root replacement. 12 patients were excluded because they were younger than 18 years; 108 in each group received the surgery they were assigned to and were analysed. There was one (<1%) perioperative death in the autograft group versus three (3%) in the homograft group (p=0.621). At 10 years, four patients died in the autograft group versus 15 in the homograft group. Actuarial survival at 10 years was 97% (SD 2) in the autograft group versus 83% (4) in the homograft group. Hazard ratio for death in the homograft group was 4.61 (95% CI 1.71-16.03; p=0.0060). Survival of patients in the autograft group was similar to that in an age-matched and sex-matched British population (96%).

INTERPRETATION

Our findings support the hypothesis that a living valve implanted in the aortic position can significantly improve the long-term outcomes in patients.

FUNDING

Funding Magdi Yacoub Institute.

Ross operation in a patient with juvenile rheumatoid arthritis

A 32-year-old woman with juvenile rheumatoid arthritis underwent a redo aortic valve replacement 7 years after a Ross procedure for severe aortic valve regurgitation. Interestingly, the cause of autograft failure was not related to the rheumatoid inflammation process.

Superior results following the Ross procedure in patients with congenital heart disease

BACKGROUND AND AIM OF THE STUDY

The Ross procedure is a versatile operation that can be applied for aortic valve replacement (AVR) in patients with congenital heart disease (CHD), including small infants and those with complex left ventricular outflow tract (LVOT) obstruction. Herein, the clinical outcome is reported following the Ross procedure in patients with CHD at the authors' institution.

METHODS

The medical records of patients who underwent the Ross procedure for CHD between 1991 and 2007 were reviewed. A competing-risks methodology was used to determine the time-related prevalence and associated factors for three mutually exclusive end states after the Ross procedure, namely death prior to subsequent cardiac reoperation, cardiac reoperation, and survival without subsequent reoperation.

RESULTS

A total of 151 patients (98 males, 53 females) was identified. The median age at the time of surgery was 8.6 years (range: 4 days to 33 years). Previously, 103 patients (68%) had undergone cardiac interventions, and 43 (28%) required LVOT enlargement (modified Ross-Konno procedure). A competing-risk analysis showed that, at 10 years after the Ross procedure, 8% of patients had died without subsequent reoperation, 26% underwent cardiac reoperation, and 66% remained alive without further reoperation. The 10-year freedom from autograft and homograft reoperation was 95% and 71%, respectively. Factors associated with early risk of mortality were age < 1 year and no prior surgical/percutaneous intervention at the time of the Ross procedure. Surgical factors associated with cardiac reoperation were concurrent cardiac surgery and the use of fresh homografts. There were no bleeding or thromboembolic complications, and the 15-year freedom from endocarditis was 95%. Ultimately, 99% of the survivors were in NYHA class I or II.

CONCLUSION

The Ross procedure remains the authors' procedure of choice for AVR in patients with CHD. Outcomes in infants aged < 1 year may improve with better patient selection and palliative surgical/percutaneous interventions prior to valve replacement. The late survival was excellent and valve-related complications were minimal. The high autograft longevity led to few patients requiring late reoperation for graft replacement.

Clinical experience with expanded use of the Ross procedure: a paradigm shift?

BACKGROUND AND AIM OF THE STUDY

The study aim was to evaluate the short-term survival and functional outcome after the Ross procedure, with expanded inclusion criteria.

METHODS

A total of 91 patients (21 females, 70 males; mean age 57.3 +/- 13.1 years; range: 0.1-74 years) underwent aortic valve replacement (AVR) with a Ross procedure at the authors' institution during the year 2007. The underlying valve diseases were stenosis in 60 patients, regurgitation in 17, and a mixed lesion in 14. Seven patients suffered from acute infective endocarditis, and in five patients the Ross operation was a reoperative procedure. Forty-four patients (48%) underwent surgery in association with concomitant procedures, which included predominantly coronary artery bypass surgery, mitral valve repair or replacement, or procedures of the ascending aorta.

RESULTS

The mean cardiopulmonary bypass and aortic cross-clamp times were 147 +/- 31 min (range: 87-246 min) and 124 +/- 26 min (range: 73-195 min), respectively. Hospital mortality was 2.2%. No patient died during the follow up period. The aortic gradient was decreased from 5.1 +/- 2 mmHg at discharge, to 3.2 +/- 1 mmHg during follow up (p < 0.05); at the same times, the mean gradient of the decellularized tissue-engineered pulmonary valve was 2.8 +/- 1 mmHg and 2.7 +/- 1 mmHg, respectively. An echocardiographic examination of neo-aortic valve competence at 12 months revealed no or trivial aortic valve regurgitation in 80 patients, and mild (grade 1+) regurgitation in nine patients. No patient required reoperation of the autograft during follow up. Two patients underwent reconstruction of the right ventricular outflow tract. At 12 months' follow up, all patients enjoyed normal social interactions, were in NYHA functional class I or II, and free from complications.

CONCLUSION

The Ross procedure can be offered as an alternative to standard prosthetic AVR with an excellent short-term outcome. The former inclusion/exclusion criteria for this procedure should be re-evaluated.

In vivo monitoring of function of autologous engineered pulmonary valve

OBJECTIVES

Clinical translation of tissue-engineered heart valves requires valve competency and lack of stenosis in the short and long term. Early studies of engineered valves showed promise, although lacked complete definition of valve function. Building on prior experiments, we sought to define the in vivo changes in structure and function of autologous engineered pulmonary valved conduits.

METHODS

Mesenchymal stem cells were isolated from neonatal sheep bone marrow and seeded onto a bioresorbable scaffold. After 4 weeks of culture, valved conduits were implanted. Valve function, cusp, and conduit dimensions were evaluated at implantation (echocardiography), at the experimental midpoint (magnetic resonance imaging), and at explant, at 1 day, and 1, 6, 12, or 20 weeks postoperatively (direct measurement, echocardiography). Histologic evaluation was performed.

RESULTS

Nineteen animals underwent autologous tissue-engineered valved conduit replacement. At implantation, valved conduit function was excellent; maximum transvalvular pressure gradient by Doppler echocardiography was 17 mm Hg; most valved conduits showed trivial pulmonary regurgitation. At 6 postoperative weeks, valve cusps appeared less mobile; pulmonary regurgitation was mild to moderate. At 12 weeks or more, valved conduit cusps were increasingly attenuated and regurgitant. Valved conduit diameter remained unchanged over 20 weeks. Dimensional measurements by magnetic resonance imaging correlated with direct measurement at explant.

CONCLUSIONS

We demonstrate autologous engineered tissue valved conduits that function well at implantation, with subsequent monitoring of dimensions and function in real time by magnetic resonance imaging. In vivo valves undergo structural and functional remodeling without stenosis, but with worsening pulmonary regurgitation after 6 weeks. Insights into mechanisms of in vivo remodeling are valuable for future iterations of engineered heart valves.

[Ross operation in Chile]

BACKGROUND

Donald Ross introduced the pulmonary autograft for aortic valve replacement with reconstruction of the right ventricular outflow tract with a homograft. Despite its advantages over conventional valve prostheses, the Ross Operation is performed in a minority of patients who need an aortic valve replacement throughout the world.

AIM

To report the operative and long term results of a series of patients subjected to Ross operation in Chile.

PATIENTS AND METHODS

Between 1996 and 2006, 131 patients aged 35+/-11 years (62% males) were subjected to an aortic root replacement with a pulmonary autograft and reconstruction of the right ventricular outflow tract with a pulmonary homograft. Seventy percent had congenital valve disease. Associated procedures were done in 39%. Patients were followed for a mean of 56+/-30 months.

RESULTS

Operative mortality was 2.3%. Two patients had the autografts replaced intraoperatively because of tears in the proximal suture line and one within a month of the operation after suffering autograft endocarditis. At last follow up all patients are in functional class 1 or 2. Autograft reoperations were done in two patients who developed dilation with valve regurgitation (both had aortic regurgitation as primary indication for aortic valve replacement). Three patients required reoperation for pulmonary homograft dysfunction. Another three patients had uneventful pregnancies with normal newborns. Actuarial freedom from any reoperation at 10 years is 93%.

CONCLUSIONS

The Ross Operation has low operative morbidity and mortality with excellent long term results. Reoperations have been rare within 10 years of follow up both for the autograft or the homograft.

Preservation of the pulmonary autograft after failure of the Ross procedure

OBJECTIVE

Failure of the pulmonary autograft following the Ross Procedure is mainly due to dilatation and/or cusp prolapse causing insufficiency. We analysed the result of pulmonary autograft valve sparing and repair, using techniques developed for native aortic root and valve.

METHODS

Of a total of 275 patients who underwent Ross operation between 1991 and 2009, 31 needed autograft re-operation. Of the 28 patients re-operated in our centre, 26 (93%) had autograft valve preservation and they represent the study cohort. At the initial Ross procedure, root remplacement technique was performed in 20 patients and autograft inclusion technique was performed in 6. Mean redo interval was 9.3 + or - 3.5 years and mean age at redo was 44 + or - 13 years. Indications for re-operations were neo-aorta dilatation (n=12; 46%), autograft insufficiency (n=4; 15%) and dilatation with autograft insufficiency (n=10; 40%). Neo-aorta dilatation was repaired using valve-sparing root replacement (n=12, 46%) or ascending aorta replacement (n=10; 40%). Cusp prolapse was repaired by commissural re-suspension (n=1), free margin plication (n=10) or re-suspension with polytetrafluoroethylene (PTFE; n=6). Cusp repair was performed in isolation (n=4) or in association with sparing (n=5) or ascending aorta replacement (n=4).

RESULTS

There was no in-hospital mortality. Two patients having undergone isolated cusp repair needed valve replacement for recurrent insufficiency after 5 days and 8 years postoperatively. At follow-up (100% complete, median: 27 months) all patients were alive, in New York Heart Association (NYHA) class I (n=22; 84%) or II (n=4; 16%). No autograft regurgitation was present in nine patients (five sparing and four ascending aorta replacement); grade I insufficiency was present in 11 (six sparing and five ascending aorta replacement), grade 2 in two (one sparing and one isolated cusp repair) and grade 3 in two (one ascending aorta replacement and one isolated cusp repair). At 3 years, overall freedom from autograft insufficiency > or = grade 3 was 80%.

CONCLUSION

Preservation of the pulmonary autograft valve can be safely performed in selected patients. At midterm, repair of neo-aorta dilatation using valve-sparing root replacement or ascending aorta replacement showed acceptable results. In contrast, results of cusp repair for isolated autograft insufficiency were unsatisfactory.

Anti-HLA antibodies and pulmonary valve allograft function after the Ross procedure

BACKGROUND AND AIM OF THE STUDY

Rejection is a plausible cause of failure of allograft valves, but has not been demonstrated unequivocally in humans. A cross-sectional study has been conducted on the frequency of anti-human leukocyte antigen (HLA) antibodies in order to identify any correlation with allograft function in adult patients, following the Ross procedure.

METHODS

Anti-HLA antibodies were determined during regular follow up (median 1.1 years postoperatively) in a random sample of 197 patients (151 males, 46 females; mean age 46 +/- 13 years). Panel-reactive antibodies (PRA) were determined by cytotoxicity testing; anti-HLA class 2 antibodies (HLA2AB) were determined by ELISA in a subgroup of 94 patients. Echocardiographic examinations were performed during the first visit and at a median of 6.8 years postoperatively.

RESULTS

The prevalence of positive antibody tests was 47% for PRA and 52% for HLA2AB. A slight deterioration of allograft valve function occurred between the two examinations (median maximal pressure gradient increased from 9 mmHg to 13 mmHg, p < 0.001; median degree of regurgitation increased from zero to trivial, p = 0.020). The degree of regurgitation was slightly, but significantly, higher in PRA-positive patients at both examinations (p = 0.008 and p = 0.038). No relationship was observed between PRA status and pressure gradients, nor between HLA2AB status and allograft valve function. Neither were any other risk factors for allograft valve deterioration identified.

CONCLUSION

Subtle, clinically irrelevant and temporally stable differences with regard to regurgitation across the allograft were observed between PRA-positive and -negative patients. These findings neither proved nor disproved rejection, but rather suggested that a slow deterioration of allograft valve function was complex, and most likely multifactorial.

Ross and Ross-Konno procedures in infants, children and adolescents: a 13-year experience

BACKGROUND AND AIM OF THE STUDY

Due to hemodynamic performance and potential for growth of the pulmonary autograft, the Ross operation is considered to be the surgery of choice for irreparable aortic valve disease in pediatric patients. The study aim was to analyze the long-term clinical and echocardiographic results of the Ross operation.

METHODS

Between February 1993 and July 2006, 55 consecutive patients (mean age 10.0 +/- 6.2 years; range: 3 months to 18 years) underwent eithera Ross operation (n=46) or a Ross-Konno procedure (n=9). The underlying left ventricular outflow tract pathology was mainly congenital (n=47). Among patients, 23 (42%) had undergone a previous aortic valve procedure. Concomitant procedures were performed in 16 patients (29%). The Ross operation was performed as a root replacement in all cases; the mean cross-clamp time was 132 min (range: 100-188 min). The autograft diameter was indexed to the body surface area and compared to normal values. The mean follow up was 5.5 +/- 3.8 years, and was 100% complete.

RESULTS

There was one early death (2%) and two late deaths (4%). The actuarial patient survival was 93% at 10 years. None of the patients developed moderate or severe autograft regurgitation. All measured maximal root diameters were above the 90th percentile of normal aortic diameter, without correlation to autograft regurgitation. Five patients (9%) had a mean homograft gradient > or = 40 mmHg, and two (4%) were reoperated on. The freedom from reoperation for homograft degeneration was 91% at 10 years.

CONCLUSION

Autograft regurgitation after the Ross and Ross-Konno procedures is uncommon, and the risk of homograft degeneration appears low. Autograft dilatation is common but does not correlate with autograft regurgitation. When considering long-term freedom from autograft and homograft degeneration, the results of the present study confirm the Ross operation as the surgery of choice for irreparable aortic valve disease in infants, children and young adults.

Thirteen years' experience with the Ross Operation

BACKGROUND AND AIM OF THE STUDY

The study aim was to evaluate 13 years' results of the Ross operation, with special attention paid to the late function of the pulmonary autograft (PA) and the right ventricular outflow tract (RVOT) allograft, in an attempt to identify risk factors that might significantly influence their late performance.

METHODS

Between May 1995 and March 2006, a total of 272 patients (mean age 30 +/- 11 years) was submitted to a Ross operation at the authors' institution. The most prevalent etiology was rheumatic disease (47%). The PA was implanted as a root replacement in 236 cases, and as an intraluminal cylinder in 36. The RVOT was reconstructed with a cryopreserved allograft in conventional fashion (n=142), with a proximal extension of the allograft with pericardium (n=46), with an allograft decellularized with deoxycholic acid (n=39), or an allograft decellularized with sodium dodecylsulfate (SDS) (n=44). The mean follow up was 67 months (range: 1-153 months: the total follow up was 1,525 patient-years.

RESULTS

Hospital mortality was 2.9% and late survival 93% at 12 years. There were two episodes of cerebral thromboembolism, and six patients developed bacterial endocarditis. Sixteen patients required reoperation for problems involving the PA and/or the RVOT allograft, progression of rheumatic mitral valve disease and iatrogenic coronary insufficiency. After 12 years, 97% and 95% of patients were free from reoperation with the PA and allograft, respectively. Over time, the PA showed increasing dimensions, and 10 patients had a diameter >45 mm. Univariate analysis revealed degenerative disease and aortic annulus >25 mm as significant risk factors for late PA dilatation. Female gender and bicuspid aortic valve were borderline factors for this type of complication. Another 14 patients had late moderate PA insufficiency, and this was correlated with a preoperative diagnosis of aortic insufficiency. Reconstruction of the RVOT with allografts decellularized with SDS were associated with lower gradients at late follow up.

CONCLUSION

Late results with the Ross operation were associated with excellent long-term survival and a low incidence of reoperations up to 13 years. Due to late PA dilatation and/or progressive valvar insufficiency, some reoperations may be expected with a longer follow up. For the RVOT reconstruction, the use of decellularized allografts with SDS may prove to be a good alternative to RVOT reconstruction.

Effect of pulmonary autograft transplantation in the surgical treatment of aortic valve disease

BACKGROUND

Aortic root replacement with pulmonary autograft (Ross procedure) has the advantages of good haemodynamics and growth potential without the need for anticoagulation. In this study, we reviewed our experience of the Ross procedure for patients with aortic valve disease.

METHODS

From October 1994 to January 2005, 42 Ross procedures were performed in our centre. There were 30 males and 12 females. The mean age was 28 +/- 15 years (range, 5-56 years). Congenital heart disease (CHD) with aortic valve stenosis (AS) and/or aortic valve insufficiency (AI) in 40 cases including one associated with ventricular septal defect (VSD), degenerated aortic valve disease with AS in 1 and subacutive bacterial endocarditis (SBE) with AI in 1 were studied. The diagnosis was made by ultracardiography (UCG) in all patients. The mean aortic valve annulus diameter (AVD) was (2.45 +/- 0.31) cm and pulmonary valve annulus diameter (MPVD) was (2.34 +/- 0.21) cm. All patients had normal pulmonary valves. The New York Heart Association (NYHA) function class was II in 36 cases and III in 6 cases. The operation was performed under moderate hypothermic cardiopulmonary bypass (CPB) with aortic root replacement using pulmonary autograft and pulmonary valve replacement with a homograft.

RESULTS

There was no early hospital mortality. Postoperative UCG showed normal aortic valve function in all our patients. The mean gradient across the aortic valve was (6.11 +/- 0.12) mmHg. The left ventricular diastole diameter (LVDD) decreased significantly from (62 +/- 5) mm to (56 +/- 3) mm (P < 0.001). The mean postoperative left ventricular ejective fraction (LVEF) was 0.49 +/- 0.23. All patients were in NYHA class I-II. Follow-up was completed in 38 cases for a mean period of 3.2 years (range 1-10 years). All survivors were in NYHA class I with normal neo-aortic and pulmonary valve function. One patient died after secondary operation due to homograft fungal endocarditis 1 year after the Ross procedure. The cause of death was uncontrolled bleeding. Another patient suffered from cardiogenic shock and was on extracorporeal membrane oxygenation (ECMO) for 10 days postoperatively. This patient was subsequently self-discharged from hospital due to financial issues and he was excluded from follow-up.

CONCLUSION

The Ross procedure is an excellent technique to treat aortic valve disease. Our data show that it can be performed safely with good early and mid-term clinical outcomes.

Early outcome after surgery for active native and prosthetic aortic valve endocarditis

BACKGROUND AND AIM OF THE STUDY

Today, the in-hospital mortality of patients treated surgically for active aortic native and prosthetic valve endocarditis remains high. The study aim was to identify the preoperative and intraoperative predictors of early outcome.

METHODS

Between January 2004 and December 2006, 75 patients (57 males, 18 females; mean age 61.6 +/- 14.1 years) underwent surgery for active native valve (NVE) or prosthetic aortic valve endocarditis (PVE).

RESULTS

Active aortic NVE was present in 49 patients (65.3%), and PVE in 26 (34.7%). Staphylococcus species were the most common infecting microorganisms in both groups, while 20 cases (26.7%) were culture-negative. Except for significantly higher preoperative renal failure (RF) in patients with PVE (p = 0.01), the clinical characteristics were equally distributed. Four patient subsets were identified based on the extent of the infectious process: (i) locally controlled NVE (38.7%); (ii) locally uncontrolled NVE (26.7%); (iii) locally controlled PVE (14.6%); and (iv) locally uncontrolled PVE (20%). Aortic valve replacement (AVR) was performed with a stentless bioprosthesis in 53 cases (70.7%), a mechanical prosthesis in eight (10.6%), and a Ross procedure in 14 (18.7%). Concomitant active mitral valve endocarditis was treated in 17 patients (22.7%). Associated procedures were performed in 14 cases (18.7%). The in-hospital mortality was 24% (n = 18). Female gender (p = 0.0147), preoperative septic or cardiogenic shock (p = 0.0275) and previous embolic events (p = 0.0129) were identified as independent predictors for in-hospital mortality. Eight late deaths occurred; the estimated overall actuarial survival was 66.6 +/- 5.6% at 12 months and 60.7 +/- 6.5% at 24 months. On Cox multiple regression, age > 70 years (p = 0.0113), preoperative RF (p = 0.0015) and mitral valve surgery due to concomitant infective endocarditis (p = 0.0363) were significant adverse predictors of late death.

CONCLUSION

Surgery for active aortic valve infective endocarditis is associated with high operative mortality and morbidity. Failure of antibiotic therapy causing septic or cardiogenic shock and delayed referral to surgery may have a detrimental effect on early outcome. Surgical eradication of cardiac infections should always be associated with the treatment of extracardiac septic foci, which could maintain a septic state and adversely influence early outcome. Adhesion to surgical guidelines, together with a multidisciplinary approach, may have a major impact on the early prognosis of these high-risk patients.

Aortic valve replacement: ten-year follow up of the Ross procedure

BACKGROUND AND AIM OF THE STUDY

The study aim was to assess the long-term results of the Ross procedure in the treatment of aortic valve disease.

METHODS

Between July 1995 and May 2006, a total of 165 patients (131 males, 34 females; mean age 39 +/- 13 years) underwent the Ross procedure using the freestanding root technique. Both, clinical and echocardiographic follow ups were conducted, with valve-associated events (death, endocarditis, thromboembolism, reoperation, valvular dysfunction) being analyzed using Kaplan-Meier curves. Log-rank tests, chi-square tests and the Cox model were used for variable analysis.

RESULTS

The mean preoperative left ventricular ejection fraction was 55 +/- 12%. Surgery was indicated for aortic stenosis (54%) or aortic insufficiency (46%). The aortic valve was bicuspid in 125 patients, while in four patients surgery was indicated in the setting of active infective endocarditis, and in six for prosthetic dysfunction. The in-hospital mortality was 2.5% (n = 4). Survival at one and 10 years was 97% (95% CI, 93-99) and 94.8% (95% CI, 89-98), respectively. Freedom from endocarditis at 10 years was 95% (95% CI, 84-98), and from valve-related events was 95% (95% CI, 90-98) and 88% (95% CI, 75-94) at one and 10 years, respectively. Four patients required reoperation (one case of recurrent mitral regurgitation after previous mitral valve repair; three cases of autograft dysfunction and disease of other valves). Based on this experience, and during the follow up period, the presence of aortic regurgitation as a baseline aortic lesion was not associated with any need for reoperation.

CONCLUSION

As a surgical technique, the Ross procedure has a low event rate at 10 years after surgery, and may be considered a valid alternative for the treatment of aortic valve disease.

[Freestyle valve for right ventricular reconstruction in Ross operation; report of a case]

A 28-year-old man with active aortic valve endocarditis underwent emergency surgery. Because he had progressive congestive heart failure and uncontrolled infection. Aortic root replacement for Ross procedure was required because of complete debridment of infective tissue. His operation were performed under extracorporeal circulation and moderate hypothermia, the operation procedure was following, (1) taking off auto-pulmonary artery valve, (2) removing dysfunctional aortic valve and auto-transplantation of pulmonary valve on aortic root, (3) putting a pulmonary Freestyle Aortic Valve to rebuild right ventricular outflow tract. Follow-up showed heart function was in class I (New York Heart Association) , aortic and pulmonary valve function was very well. Streptococcus milleri group was isolated from his blood and infectious aortic valve postoperatively. We believed that a Ross operation with Freestyle Aortic Valve is more resistant to infection, therefore, it might be an option for infective endocarditis with aortic valve endocarditis.

Fifty-two months' mean follow up of decellularized SynerGraft-treated pulmonary valve allografts

BACKGROUND AND AIM OF THE STUDY

It has been reported previously that the use of a decellularized pulmonary allograft (SynerGraft; CryoLife Inc.) for right ventricular outflow tract reconstruction in adults is associated with reduced immunization. The implantation appeared to be safe, but was not associated with any detectable clinical or echocardiographic advantage. The study aim was to follow further the outcome of SynerGraft patients.

METHODS

Twenty-three adult patients (19 males, four females) each received a SynerGraft-allograft during a Ross procedure. A further 49 patients (37 males, 12 females) who underwent a Ross procedure using a conventional pulmonary allograft during the same period served as controls. Follow up examinations using transthoracic echocardiography in standard views was performed on a regular basis. The latest follow up was performed after a mean of 52 months.

RESULTS

Directly after implantation, there were no echocardiographic differences between the two groups, but with time the pressure gradients increased significantly (p <0.001) in both groups. At the latest follow up, pressure gradients were slightly higher across the SynerGraft-allograft valves than across conventional allografts (Pmax 18.2 +/- 9.0 versus 14.0 +/- 6.9 mmHg, respectively; p = 0.049). On regression analysis (considering pre- and intraoperative variables), 'SynerGraft-allograft' was the only variable predicting the increase in pressure gradient from its postoperative value to that at follow up. However, no clinical differences were observed between the groups.

CONCLUSION

The present results relate to the longest follow up on decellularized pulmonary SynerGraft-allografts conducted to date. No reoperations were required after a mean follow up of 52 months, and the echocardiographic results were stable after the first postoperative year. Based on these data, the use of pulmonary SynerGraft-allograft valves in adults appears not to provide any advantage over conventional allografts, although further follow up is warranted before any final judgment is made regarding this new technology.

Prosthetic heart valves: Types and echocardiographic evaluation

In the last five decades multiple different models of prosthetic valves have been developed. The purpose of this article is to provide a comprehensive source of information for the types and the echocardiographic evaluation of the prosthetic heart valves.

Analysis of 92 mitral pulmonary autograft replacement (Ross II) operations

OBJECTIVE

The study objective was to find a mitral valve substitute that does not require lifelong anticoagulation and is not affected by tissue degeneration in the long term.

METHODS

Between July 14, 1997, and August 8, 2004, a total of 92 patients with irreparable mitral valve disease underwent mitral valve replacement with the pulmonary autograft encased within a Dacron tubing for support. In 4 patients, the autograft had to be sacrificed at the initial operation. Of the remaining 88 patients, 62 were female, and the age ranged from 4 to 64 years (mean 39 years). Eighty-six patients had rheumatic mitral disease, and 2 patients had congenital mitral disease.

RESULTS

Operative transesophageal echocardiography initially showed adequate valve characteristics (mean valve area 2.8 cm2, mean gradient 3.9 mm Hg, no significant regurgitation) in all 88 patients. Operative mortality was 4.6%, and late mortality definitely related to the operation was 7.9%. Four patients were lost to follow-up; the mean follow-up was 60 months. Progressive regurgitation and stenosis developed in 9 patients over 2 to 5 years, 4 of whom had their grafts explanted. The autograft was explanted in 1 patient because of endocarditis. Mild pulmonic stenosis developed in 3 patients, and critical pulmonic stenosis developed in 1 patient. At 5 years follow-up, freedom from degeneration was 93.4%, freedom from reoperation was 94.2%, and freedom from all death was 86.0%.

CONCLUSION

Although the Ross II operation is difficult and harbors significant risk, it remains an option for patients with irreparable mitral disease who have a long life expectancy and who cannot be placed on lifelong anticoagulation.

Are heart valves from donors over 65 years of age morphologically suitable for transplantation?

Since there is no upper age limit for general organ donation, unlike heart valve donation, and since a quarter of all organ donors are 65 years and older, we examined whether the heart valves from these donors are suitable as allografts. In the period 1999-2004 the aortic valve and pulmonary valve of 100 organ donors above 65 years of age were examined to establish whether they would have been suitable as valve grafts. To compare the valve grafts above and below the age limit of 65 years, we used data on the aortic and pulmonary valves of 380 organ donors below the age limit in the same time period. Examination of the 200 heart valves showed that - just like valves from donors below the age limit - 100 of them would have met the medical quality standards for transplantation, which discriminate among optimal, suitable and unsuitable tissue morphology. The morphological suitability of the aortic valves decreases rapidly during the 4th decade of life and near to the age limit only 6% of them are accepted as grafts. The rate of potentially acceptable aortic valve grafts from organ donors aged over 65 years of 15% is also small. By contrast, the pulmonary valves are not affected by age-related tissue changes that might reduce their transplantability. The predominant majority (85%) of potential pulmonary valve grafts from organ donors over 65 years of age fulfilled the acceptance criteria, half of them (48%) even showing good tissue quality. In light of these results the age limit was raised to 70 years in 2005.