Comparison of the aortic homograft and the pulmonary autograft for aortic valve or root replacement in children

To assess late results of aortic homograft and pulmonary autograft valves implanted into the left ventricular outflow tract of children, we reviewed the case histories of 146 patients 18 years of age or younger who underwent aortic valve or root replacement between November 1964 and April 1990. One hundred three patients (mean, 12 +/- 3.9 years) received an aortic homograft and 43 (mean, 14 +/- 4.1 years) had their own pulmonary valve transferred to the aortic position. There were 54 valve and 49 root replacements with homografts and 36 valve and seven root replacements with autografts. Hospital mortality rate was 15.5% (16 patients) in the homograft group and 11.6% (five patients) in the autograft group. Survivors were followed up for a total of 867 (homograft) and 297 (autograft) patient-years. The late mortality rate was 16.7% (1.9% per patient-year) for patients with homografts and 13.2% (4.4% per patient-year) for patients with autografts, whereas the incidence for reoperation per patient-year was 2.9% and 2.0%, respectively. At 15 years actuarial rates for homografts and autografts for freedom from reoperation were 54% +/- 8.1% and 68% +/- 11.1%; freedom from endocarditis, 97% +/- 2.4% and 75% +/- 10.2%; and freedom from any complication, 41% +/- 6.5% and 50% +/- 10.3%. Valve degeneration occurred in 19 homografts (2.2% per patient-year), whereas there was no definite instance of primary tissue failure among the pulmonary autografts. This experience would indicate that either the homograft or the autograft valve can be used with acceptable results in children. However, the pulmonary autograft gives better long-term performance and, if growth potential is realized, may be the ideal valve substitute in children.     

Geometric mismatch between homograft (allograft) and native aortic root: a 14-year clinical experience.

OBJECTIVES: We evaluated the effect of homograft/native aortic root geometric matching and mismatching on valve survival and myocardial remodeling. METHODS: Between January 1, 1987 and March 2000, a total of 292 patients, aged 1.5-78 years (mean, 46.2 years), underwent freehand subcoronary aortic valve (AVR; n=207) and root (ARR; n=85) replacement with matched and mismatched cryopreserved homografts. All patients had pre- and postoperative two-dimensional Doppler echocardiographic studies. Two-hundred and forty-three survivors, excluding children with complete data on sizing, were followed at a total follow-up time of 1269 patient-years. Seventy percent received matched and 30% received mismatched aortic homografts. The homograft valve sizes ranged from 19 to 28 mm. RESULTS: Hospital death for elective first operation was 2.3%, and late death after a mean follow-up of 52 months was 7.9%. The patient survival at 14 years was 92+/-2%. By linear regression analysis, matched homografts were equal to or 1-2 mm less than the native aortic annulus (r(2)=0.73). The valve survival in patients with AVR and ARR was 72+/-4 and 80+/-8% at 14 years, respectively. The freedom from reoperation was 92+/-5, 77+/-4 and 48+/-10% at 14 years for matched, oversized and undersized homografts, respectively (P=0.001). The postoperative cardiac index of patients with 22 and 24 mm homografts was 3.8-4.1 l/m(2), and there was a regression of the left ventricular mass and end-diastolic diameter (P=0.001). CONCLUSIONS: The aortic homograft offers an excellent long-term clinical result. A mismatched homograft is a risk factor for postoperative aortic incompetence, reinfection with pseudoaneurysmal formation and reoperation for the freehand subcoronary implantation technique during the first 7 years of the postoperative period. It is prudent therefore to avoid mismatched homografts and use rather a properly sized stentless xenograft if a root replacement is not indicated.     

Medium-term results of aortic valve replacement with cryopreserved homograft valves: importance of a domestic homograft valve bank

There are advantages to using aortic homografts as aortic valve replacements (AVR), particularly in patients with complex infective endocarditis. To determine the importance of a domestic homograft valve bank, our 23 surgical cases of homograft-AVR were reviewed. Since 2000, the Tissue Bank of the National Cardiovascular Center has supplied 23 aortic homograft valves for the treatment of complex aortic valve endocarditis. Fourteen of 23 patients had prosthetic valve endocarditis and 20 patients had an aortic annular abscess. The early mortality rate was 17% (4 patients), in all of whom prosthetic valve replacement had been performed previously. No recurrent endocarditis and no recurrent aortic regurgitation were noted at medium-term follow-up. An aortic homograft valve is the conduit of choice in cases of infective endocarditis and the importance of a domestic homograft valve bank should be recognized.     

复杂性感染性心内膜炎的外科治疗

目的评价瓣周脓肿、心肌脓肿以及瓣膜严重毁损等复杂性感染性心内膜炎手术治疗的近、远期疗效.方法回顾性分析1988年12月至2002年6月手术治疗的复杂性心内膜炎患者57例临床资料,均为原发性心内膜炎,其中感染侵犯主动脉瓣25例、二尖瓣16例、二尖瓣和主动脉瓣16例.术中发现瓣叶严重毁损32例、主动脉瓣周脓肿19例、主动脉根部环形脓肿导致左心室-主动脉连接破坏4例、二尖瓣后瓣环脓肿11例、心肌脓肿6例、瓣膜赘生物形成55例.脓肿清除后遗留残腔采用间断褥式缝合6例、自体心包片修补19例、牛心包片修补6例、聚四氟乙烯膨体补片修补4例;施行以带瓣管道作升主动脉根部替换和左、右冠状动脉移植术4例,主动脉瓣替换术21例,二尖瓣替换术16例,主动脉瓣及二尖瓣双瓣替换术16例.结果早期死亡6例(11%),死亡主要原因为低心输出量综合征、人造心脏瓣膜性心内膜炎和多脏器功能衰竭.随访4个月至14年,平均(5.93±0.20)年.晚期死亡5例,晚期主要并发症为人造瓣膜性心内膜炎.术后1年心功能恢复NYHA分组Ⅰ～Ⅱ级占96%(44/46);5年再手术免除率为(84±3)%,5年实际生存率为(61±9)%.结论复杂性心内膜炎局部组织破坏较多,应限期手术或急症手术,清创后残腔的处理是影响手术本身能否成功以及术后近、远期效果的关键.     

Reoperation after fresh homograft replacement: 23 years' experience with 655 patients.

OBJECTIVE: Through a retrospective study on the use of fresh homografts in 655 aortic valve replacement patients over a period of 23 years, we aimed to assess the reasons for eventual reoperation and causes of valve dysfunction. METHODS: Between January 1980 and December 2002, 655 patients received fresh homografts. All homografts were antibiotic sterilized and stored at 4 degrees C. During this time, 139 patients (116 male and 23 female) with a mean age of 46.7 years (range 18-72) required reoperation. RESULTS: The 30-day hospital overall mortality was 2.87%. The mean durability for all homografts was 12.4+/-4.54 years (1 month to 23 years). The cumulative rates for freedom from reoperation for any cause were 94.09+/-2% at 5 years and 87.9%+/-4% at 10 years, 76.6 at 15 years, 49.55 at 20 years. The major cause of valve dysfunction and indication for reoperation was degeneration in 111 patients (79.8%). Predominant aortic valve insufficiency in 87 patients (62.5%) and predominant stenosis in 24 patients (17.26%). Endocarditis occurred in 21 patients (15.1%). Early endocarditis was diagnosed in five patients (3.59%), late endocarditis in 16 patients (11.5%). Additional causes for reoperation included ascending aortic aneurysm, mitral valve insufficiency and congestive cardiomyopathy. Seventeen patients (12.2%) required concomitant procedures. Coronary artery bypass grafting was performed in six cases (4.3%), mitral valve replacement in five cases (3.59%), mitral valve annuloplasty in six (4.3%). The primary reoperative procedure was artificial/mechanical aortic valve implantation. In five cases, St. Jude Medical conduit grafts were implanted due to ascending aortic aneurysms. Homograft reimplantation was performed in four cases. One patient underwent mitral valve replacement and one patient received a heart transplant. CONCLUSION: The results of the study suggest that reoperation in patients with aortic homografts is a low-risk procedure as compared to alternative therapies. Primary allograft aortic valve replacement can give acceptable results for up to 23 years. The major cause of valve dysfunction and indication for reoperation was degeneration. Cumulative rates for freedom from reoperation for any cause in age groups suggest careful selection and indications in homograft implantation in the younger patients. Young age is a risk factor for an early homograft structural deterioration (degeneration).     

Reoperation after fresh homograft replacement: 23 years’ experience with 655 patients

Objective: Through a retrospective study on the use of fresh homografts in 655 aortic valve replacement patients over a period of 23 years, we aimed to assess the reasons for eventual reoperation and causes of valve dysfunction. Methods: Between January 1980 and December 2002, 655 patients received fresh homografts. All homografts were antibiotic sterilized and stored at 4 °C. During this time, 139 patients (116 male and 23 female) with a mean age of 46.7 years (range 18–72) required reoperation. Results: The 30-day hospital overall mortality was 2.87%. The mean durability for all homografts was 12.4±4.54 years (1 month to 23 years). The cumulative rates for freedom from reoperation for any cause were 94.09±2% at 5 years and 87.9%±4% at 10 years, 76.6 at 15 years, 49.55 at 20 years. The major cause of valve dysfunction and indication for reoperation was degeneration in 111 patients (79.8%). Predominant aortic valve insufficiency in 87 patients (62.5%) and predominant stenosis in 24 patients (17.26%). Endocarditis occurred in 21 patients (15.1%). Early endocarditis was diagnosed in five patients (3.59%), late endocarditis in 16 patients (11.5%). Additional causes for reoperation included ascending aortic aneurysm, mitral valve insufficiency and congestive cardiomyopathy. Seventeen patients (12.2%) required concomitant procedures. Coronary artery bypass grafting was performed in six cases (4.3%), mitral valve replacement in five cases (3.59%), mitral valve annuloplasty in six (4.3%). The primary reoperative procedure was artificial/mechanical aortic valve implantation. In five cases, St. Jude Medical conduit grafts were implanted due to ascending aortic aneurysms. Homograft reimplantation was performed in four cases. One patient underwent mitral valve replacement and one patient received a heart transplant. Conclusion: The results of the study suggest that reoperation in patients with aortic homografts is a low-risk procedure as compared to alternative therapies. Primary allograft aortic valve replacement can give acceptable results for up to 23 years. The major cause of valve dysfunction and indication for reoperation was degeneration. Cumulative rates for freedom from reoperation for any cause in age groups suggest careful selection and indications in homograft implantation in the younger patients. Young age is a risk factor for an early homograft structural deterioration (degeneration).     

Redo aortic root surgery for failure of an aortic homograft is a major technical challenge

OBJECTIVE: Aortic homografts offer many advantages over prosthetic valves. However, homograft dysfunction due to degeneration or infection may lead to reoperation. Aortic valve replacement in patients who have undergone previous aortic root replacement with an aortic homograft remains a technical challenge. To assess reoperation events a retrospective review was conducted. MATERIALS AND METHODS: From January 2000 to October 2006, 20 consecutive patients (38.8+/-14.9 years old) underwent repeat surgery for aortic homograft failure. RESULTS: Reoperation was performed 7.2+/-3.5 years after implantation of the aortic homograft as a root. Indication was homograft degeneration (n=18 [90%]) and endocarditis (n=2 [10%]). In patients with major homograft wall calcifications or endocarditis, nine aortic root reconstructions were performed (Bentall procedure n=7; homograft implantation n=2). Each homograft was dissected with electrical cauterization and removed 'en-bloc' sparing the coronary buttons. In case of flexible homograft wall, stented prostheses (mechanical n=10, bioprosthesis n=1) were implanted along the homograft annulus. Additional procedures consisted of mitral valve replacements (n=8), tricuspid repairs (n=4), Konno procedure (n=1) and coronary bypass (n=5). Perioperative complications occurred in seven (35%) patients: sternal re-entry accident (n=2); reoperations for mediastinitis (n=1) or bleeding (n=2); renal insufficiency (n=1); total heart block (n=1). No association was found between operative procedures and postoperative complications (Fisher's exact test). Two patients (10%) died from multiorgan failure in the early postoperative period. In total, 94.4% of the survivors remained free from reoperation at 74 months. CONCLUSION: Reoperation on patients with an aortic homograft as a root presents a relatively high perioperative morbidity. The surgical strategy depends on the degree of homograft wall calcification.     

Immediate and long-term results of valve replacement for native and prosthetic valve endocarditis

BACKGROUND: The objective of the present study was to compare current results of prosthetic valve replacement following acute infective native valve endocarditis (NVE) with that of prosthetic valve endocarditis (PVE). Prosthetic valve replacement is often necessary for acute infective endocarditis. Although valve repair and homografts have been associated with excellent outcome, homograft availability and the importance of valvular destruction often dictate prosthetic valve replacement in patients with acute bacterial endocarditis. METHODS: A retrospective analysis of the experience with prosthetic valve replacement following acute NVE and PVE between 1988 and 1998 was performed at the Montreal Heart Institute. RESULTS: Seventy-seven patients (57 men and 20 women, mean age 48 +/- 16 years) with acute infective endocarditis underwent valve replacement. Fifty patients had NVE and 27 had PVE. Four patients (8%) with NVE died within 30 days of operation and there were no hospital deaths in patients with PVE. Survival at 1, 5, and 7 years averaged 80% +/- 6%, 76% +/- 6%, and 76% +/- 6% for NVE and 70% +/- 9%, 59% +/- 10%, and 55% +/- 10% for PVE, respectively (p = 0.15). Reoperation-free survival at 1, 5, and 7 years averaged 80% +/- 6%, 76% +/- 6%, and 76% +/- 6% for NVE and 45% +/- 10%, 40% +/- 10%, and 36% +/- 9% for PVE (p = 0.003). Five-year survival for NVE averaged 75% +/- 9% following aortic valve replacement and 79% +/- 9% following mitral valve replacement. Five-year survival for PVE averaged 66% +/- 12% following aortic valve replacement and 43% +/- 19% following mitral valve replacement (p = 0.75). Nine patients underwent reoperation during follow-up: indications were prosthesis infection in 4 patients (3 mitral, 1 aortic), dehiscence of mitral prosthesis in 3, and dehiscence of aortic prosthesis in 2. CONCLUSIONS: Prosthetic valve replacement for NVE resulted in good long-term patient survival with a minimal risk of reoperation compared with patients who underwent valve replacement for PVE. In patients with PVE, those who needed reoperation had recurrent endocarditis or noninfectious periprosthetic dehiscence.     

Surgical management for active infective endocarditis: A single hospital 10 years experience

Objective  Surgical treatment of active infective endocarditis (IE) requires not only homodynamic repair, but also, special emphasis on the eradiation of the infection to prevent recurrence. This study was undertaken to examine the outcome of surgery for active infective endocarditis. Methods  One hundred sixty-four consecutive patients (pts) underwent valve surgery for active IE in Madani Heart Centre (Tabriz, Iran) from 1996 to 2006. Patients presenting with IE diagnosis (according to Duke Criteriaset) were eligible for study. Results  The mean age of patients was 36.3±16 years overall: 34.6±17.5 years for native valve endocarditis and 38.6±15.2 years for prosthetic valve endocarditis (p=0.169). Ninety one (55.5%) of patients were men. The infected valve was native in 112 (68.3%) of patients and prosthetic in 52 (31.7%). In 61 (37%) patients, no predisposing heart disease was found. The aortic valve was infected in 78 (47.6%), the mitral valve in 69 (42.1%), and multiple valves in 17 (10.3%) of patients. Active culture-positive endocarditis was present in 81 (49.4%) whereas 83 (50.6%) patients had culture-negative endocarditis. Staphylococcus aureus was the most common isolated microorganism. Ninety patients (54.8%) were in NYHA classe III and IV. Mechanical valves were implanted in 69 patients (42.1%) and bioprostheses in 95 (57.9%), including homograft in 19 (11.5%). There were 16 (9%) operative deaths, but there was only 1 death in patients that underwent aortic homograft replacement. Reoperation was required in 18 (10.9%) of cases. On multivariate logistic regression analysis, Staphylococcus aureus infection (p=0.008), prosthetic valve endocarditis (p=0.01), paravalvular abscess (p=0.001) and left ventricular ejection fraction less than 40% (p=0.04) were independent predictors of inhospital mortality. Conclusions  Surgery for infective endocarditis continues to be challenging and associated with high operative mortality and morbidity. Prosthetic valve endocarditis, impaired ventricular function, paravalvular abscess and Staphylococcus aureus infection adversely affect in-hospital mortality. Also we found that aortic valve replacement with an aortic homograft can be performed with acceptable in hospital mortality and provides satisfactory results.     

Short-term result of aortic valve replacement with cryopreserved homograft valve in the University of Tokyo Tissue Bank

The short-term results after aortic root replacement with 11 cryopreserved aortic homografts was examined. Since 1998, the University of Tokyo Tissue Bank has supplied 11 aortic homograft valves. Nine of the recipients were male, and the average age was 51.2 years. Nine out of 11 patients had suffered from a serious condition of native or prosthetic valve infectious endocarditis. All of the patients underwent aortic root replacement, and the blood type between the patient and the homograft was matched in 8 of the patients. Only 1 patient died (9.1%) in the short-term due to sepsis. The preoperative degree of aortic valve regurgitation in all of the cases was third or fourth while the regurgitation disappeared after the operation in all of them. Thinking of the serious condition of our cases preoperatively, the 9.1% operative mortality was quite acceptable. Long-term follow-up is necessary to estimate the quality of the homografts.     

Reoperations in valvular heart disease

Background Reoperations for valvular heart disease are associated with a higher overall mortality than the primary operations. In this retrospective analysis, we present our experience of reoperative valvular heart surgery over a period of 25 years. Methods From January 1975 to July 2000, 13039 operations were performed for valvular heart disease. Of these 665 were reoperations. The mean age of the patients at the primary operation was 24.0±10.2 years (range: 8 to 65 years) and at re-operation was 35.6±11.6 years (range: 9 to 65 years) with an interval of 9.4±2.2 years (range: 0.2 to 25 years) between the 2 procedures. Four hundred and forty reoperations were performed following a previous closed mitral valvotomy and procedures included, redo closed mitral valvotomy (n=28), mitral valve replacement (n=30), open mitral commissurotomy (n=51), mitral valve repair (n=9), homograft mitral valve replacement (n=2), double valve replacement (n=47), aortic valve replacement (n=2) and homograft aortic valve replacement plus open mitral commissurotomy (n=l). Eighty six patients underwent reoperations following mitral valve replacement. Valve thrombosis (n=50) and endocarditis (n=10) were principle causes of reoperation. Forty three patients required reoperation following failed mitral valve repair, 19 following open mitral commissurotomy and 8 following homograft mitral valve replacement. Sixty five patients underwent reoperation following aortic valve operations: prosthetic aortic valve replacement in 43, homograft aortic valve replacement in 5, aortic valve repair in 10, and Ross procedure in 7. Results Majority of patients were operated through midsternotomy. Aortic cannulation was possible in all but 4 patients in whom femoral artery cannulation was required. Operative mortality following reoperations was 7.5% (n=50). Peri-operative bleeding, low cardiac output and infective endocarditis were major causes of operative deaths. Other post-operative complications included cerebrovascular accident (n=3), acute renal failure (n=10) and jaundice (n=25). Fifteen patients developed significant wound infection. Conclusions Patients undergoing operation for valvular heart disease frequently require reoperation. Reoperative valvular heart surgery is safe and can be undertaken with acceptable mortality and morbidity.     

Surgical aspect of active infective endocarditis

Twenty patients with active infective endocarditis, 11 with native valve endocarditis (NVE) and 9 with prosthetic valve endocarditis (PVE), were treated surgically from 1975 through April 1987 at Kyushu University Hospital. The operative indications were congestive heart failure mainly due to massive aortic regurgitation in 18, periannular abscess in 6, major embolism in 5 and severe hemolysis in 3 patients. In the group of NVE, single aortic valve replacement was performed in 4 patients and multiple valve replacement in the remainder. One patient died early postoperatively from LOS. Two patients with recurrent infective endocarditis, which occurred within 60 days after previous prosthetic valve replacement, were operated subsequently as early PVE. All other patients became NYHA class I postoperatively except for one patient who died from thrombosed valve. In the group PVE, re-AVR was done in 3, re-MVR in five, double valve replacement in two and re-fixation of the prosthesis to the aortic annulus in one patient. Two patients with early PVE died from recurrent endocarditis late postoperatively. One of 7 patients with late PVE, who had suffered from myocardial and cerebral infarction before reoperation, died from multiple organ failure. There were 3 patients with perivalvular leakage due to late active PVE, whose preoperative signs of inflammation were negative or minimum. As recurrent perivalvular leakage due to persistent infective endocarditis might frequently occur in such cases, complete resection and debridement of infected foci should be emphasized.     

Advantage of autograft and homograft valve replacement for complex aortic valve endocarditis

Background. There are advantages to using homografts and autografts as aortic valve replacements, particularly in patients with infective endocarditis. To better define these advantages, we reviewed our 13-year experience with the surgical management of infective endocarditis involving the aortic valve and root.

Methods. From 1986 through 1998, 81 adults with aortic valve endocarditis underwent valve replacement (AVR). The mean age of the 65 men and 16 women was 44 ± 14 years. Sixty-three (78%) patients had active endocarditis at the time of operation. Non-native valve endocarditis was present in 29 (36%) patients, in 9 of whom the infection was a recurrence. Aortic valve replacements were performed with 46 homografts (homo-AVR), 25 autografts (Ross-AVR), and 10 prosthetic valves (prosth-AVR). Among Ross-AVR and homo-AVR patients, 11 required mitral valve replacement or repair (homo-Ross DVR). Follow-up was 90% complete within 2 years of the end of the study with a mean of 3.7 ± 3.4 years.

Results. Early mortality was 16% (13 of 81 patients). This was 12% (3 of 25 patients) for Ross-AVR, 17% (8 of 46 patients) for homo-AVR, and 20% (2 of 10 patients) for prosth-AVR. Overall late mortality was 10% (7 of 68 patients) with a valve-related late mortality of 7% (5 of 68 patients). Actuarial survival at 5 years was 88% ± 9% in Ross-AVR, 69% ± 11% in homo-AVR, and 29% ± 22% in prosth-AVR (p = 0.03). Endocarditis recurred in 12.5% (1 of 8 patients) with prosth-AVR and 3% (2 of 60 patients) in homo-Ross AVR.

Conclusions. Valve replacement in the presence of native and prosthetic endocarditis remains a formidable challenge. Autografts and homografts are the preferred replacement aortic valves for these patients even if concomitant mitral valve replacement is required, and risk of valve-related death or recurrent endocarditis is low at medium-term follow-up.     

A case report of translocation method for active infective aortic valve endocarditis with aortic root abscesses]

We experienced a case of 51-year-old woman who underwent emergency aortic valve replacement by translocation method for active infective aortic valve endocarditis with aortic root abscesses. Postoperative course was complicated as the following. Three days later, the perforation of noncoronary sinus of Valsalva into the right atrium was noted and she developed progressive heart failure due to the massive left-to-right shunt. The second operation was performed immediately for the patch closure of the perforation through the right atriotomy. Two months later, unstable angina appeared because of the stenosis of the vein graft to the left coronary artery, leading to the emergency third operation in which LITA was placed to the left anterior descending artery. In spite of these complications she recovered gradually and she was discharged 6 months after the first operation. She is now doing well in NYHA class 2. Translocation method is quite useful for such a case of the aortic valve endocarditis with periannular abscesses in whom conventional valve replacement is supposed to be impossible, but the long durability of this type of the repair is unknown. Careful follow-up of the patient is mandatory.     

Infective endocarditis associated with a scorpion sting

We report the successful surgical intervention in two cases of aortic valve bacterial endocarditis after scorpion stings. Infective endocarditis developed in both patients several weeks after they suffered repeated scorpion stings. Both patients had similar, but uncommon features: (1) the isolated organisms were unusual causes of infective endocarditis (streptococcus group G and Streptococcus milleri), (2) annular abscesses developed that required either aortic root replacement with a homograft or annular patch repair with pericardium, and (3) complete heart block developed postoperatively, requiring permanent pacemaker implantation. Both patients completed a 6-week postoperative course of antibiotic therapy and are without recurrent infection.     

Early and late results of aortic root replacement with antibiotic-sterilized aortic homograft

Between November 1972 and November 1986, 108 patients aged 5 to 73 years had complete replacement of the aortic root with an aortic homograft into which the coronary arteries were implanted. The main indications were (1) a tunnel type of aortic obstruction involving a hypoplastic ring, (2) a para-aortic annular abscess, (3) prosthetic valve dysfunction, mainly a previous aortic homograft, and (4) aortic stenosis with a small aortic anulus. Eighty-four patients (78%) had previous aortic valve operations. Concomitant cardiac procedures were done in 34 patients (32%). The 30-day mortality rate was 14% (15 patients). The cumulative follow-up period was 180.3 patient-years. The late mortality rate was 6.1% per patient-year (11 patients). The patients were not given anticoagulants postoperatively, but the entire group has been completely free from thromboembolism. The actuarial 5-year survival rate including operative deaths was 72%. The freedom from valve-related death at 5 years after operation is 86% and freedom from reoperation at 5 years is 96%. The use of homografts for replacement of the aortic valve and root in patients with complex lesions affecting these structures has shown encouraging early and late results, with regard to both survival and valve performance.     

An experience with the Ross operation utilizing cryopreserved pulmonary homografts procured by and stored in our homograft valve bank

Eight patients, 4 males and 4 females ranging in age from 10 to 54 years (mean 27 +/- 13 years) underwent the Ross operation using a cryopreserved pulmonary homograft harvested by and cryopreserved in our institutional "Tissue Bank". Seven patients had a congenital bicuspid aortic valve and 3 patients had had healed infective endocarditis of the aortic valve. Four young female patients wanted to have a baby after operation. The Ross procedure was carried out utilizing aortic root replacement techniques in all patients. All patients survived and are currently in NYHA class 1, but 2 cardiac events occurred in 2 patients during the mean follow-up term of 29 +/- 19 months. The one was the anastomic stenosis between the homograft and distal pulmonary artery treated by balloon dilatation and the other was ventricular tachycardia eventually managed by the insertion of an ICD. Pulmonary autograft valve regurgitation is present in 3 patients, but it is not progressive up to the present time. Pulmonary homograft valves function well in all patients. The Ross operation for adolescents and young adults should become more popular along with more easy availability of homograft valves based upon the establishment of the "Homograft Valve Bank" system in Japan.     

Homograft aortic root replacement to correct infective endocarditis requiring seven open cardiac procedures

Infective endocarditis, presumably from a septic dental focus, affecting the aortic valve was seen as acute aortic regurgitation in a 20-year-old woman. Seven open cardiac procedures for replacement of the aortic valve and left ventricular outflow tract were performed over the subsequent 6 years. Aortic root replacement using a fresh antibiotic-sterilized homograft was performed as the last definitive operative procedure. This article is presented to highlight (1) the use of homograft aortic root replacement for extensive involvement of aortic valve and left ventricular outflow tract in cases of infective endocarditis and (2) the feasibility of multiple sternal reentries when indicated.     

Long-term performance of 555 aortic homografts in the aortic position

Long-term results with 555 aortic homografts used for isolated aortic valve replacement (AVR) between 1964 and 1986 were analyzed to assess valve performance and the time-related onset of valve-related events. The total follow-up was 2,931 patient-years. Twenty years after operation, overall survival was 51.6 +/- 8.1%, freedom from valve-related death was 67.1 +/- 8.9%, freedom from primary tissue failure was 12.4 +/- 4.8%, freedom from infective endocarditis was 82.7 +/- 4.3%, freedom from surgical technical failure was 88.1 +/- 2.3%, and freedom from all complications including valve-related death was 9.0 +/- 3.5%. The incidence of thromboembolism was 0.034% per patient-year (one potential event). Long-term results after homograft insertion for aortic stenosis were significantly better than those after insertion for aortic incompetence. It is concluded that the good quality of life and the median life expectancy, which extends more than 20 years after operation, make the homograft an excellent choice for AVR.     

Viable and nonviable aortic homografts in the subcoronary position: a comparative study

One hundred fifty-five freeze-dried, 63 frozen, and 337 Hanks'-antibiotic solution preserved or nutrient-antibiotic solution preserved homografts used for isolated aortic valve replacement have been followed for 1 to 20 years (mean, 5.3 years), a total of 2,931 patient-years of follow-up information. Overall survival, valve-related death, primary tissue failure, failure due to surgical technical error, infective endocarditis, and overall event-free survival have been assessed and compared. Overall survival 20 years after operation was 51.6% +/- 8.1% with a low incidence of sudden death. The method and length of preservation did not have any effect on the long-term performance or the mode of failure of the homografts. The rate of primary tissue failure was apparently higher with valves preserved in a solution containing calf serum, but the difference was not significant. It is concluded that long-term patient survival and quality of life after aortic valve replacement with a homograft are excellent. The current study, however, could not verify the existence of a significant difference between the three assessed methods of homograft preservation. Furthermore, it could not prove the importance of cellular viability or the existence of clinically significant immunological factors other than the calf serum content of the nutrient medium.