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.     

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.     

Redo aortic root replacement: experience with 31 patients

BACKGROUND: Aortic root re-replacement is being performed with increased frequency. Limited information is available regarding the surgical approaches and clinical outcomes of this reoperation. METHODS: Between May 1980 and May 1999, 31 patients (mean age, 45 +/- 15 years) underwent redo composite replacement of the aortic valve and ascending aorta. Indications for reoperation were prosthetic valve endocarditis in 12 patients (39%), failed biological valve in 17 (55%), and false aneurysm in 2 (6%). At reoperation, mechanical valves were implanted in 24 patients and biologic valves in 7. All patients with endocarditis had annular abscess and required reconstruction of the left ventricular outflow tract before implantation of a new valved conduit. Mechanical valves were used in 24 patients, aortic homograft in 4, and bioprosthetic valves in 3. The coronary button technique was used to reimplant the coronary arteries whenever possible. Extension of one or both coronary arteries with a short segment of saphenous vein or a synthetic graft was used in 16 patients (52%). The aortic arch was replaced in 7 patients (23%). RESULTS: There was one operative death (3%) because of rupture of an abdominal aortic aneurysm. The mean follow-up was 47 +/- 46 months and was 100% complete. There were five late deaths (16%), three of which were cardiac related. The actuarial survival was 71% +/- 12% at 5 years. Three patients experienced recurrent prosthetic valve endocarditis 4 months to 8 years after operation. The 8-year freedom from endocarditis for patients operated on for endocarditis was 82% +/- 11% compared with 100% for those operated on for other reasons (p = 0.1). At the last follow-up, 21 of 25 survivors (84%) were in New York Heart Association functional classes I or II, and 4 were in class III. CONCLUSIONS: Redo aortic root replacement can be performed with good early and late results. Patients operated on for prosthetic root endocarditis may have an increased risk of recurrent late endocarditis.     

Reoperative cryopreserved root and ascending aorta replacement for acute aortic prosthetic valve endocarditis

BACKGROUND: Prosthetic aortic valve endocarditis (PVE) is an important complication of aortic valve replacement (AVR) and is a particularly difficult situation after an operation combining AVR with ascending aortic replacement. METHODS: From 1988 through 2000, 27 patients with aortic valve PVE after previous ascending aortic replacement (aortic root replacement in 13, aortic valve replacement with a supracoronary graft in 14) underwent reoperation for aortic root replacement with a cryopreserved aortic allograft and prolonged intravenous antibiotic therapy. All patients were considered to have active PVE (25 with positive cultures); root abscess formation was present in 89% and aortoventricular discontinuity in 41%. RESULTS: One patient (3.7%) died in-hospital, and permanent pacemakers were required in 10 patients (37%). Mean postoperative follow-up interval was 3.9 +/- 3.0 years, and survival at 1, 2, 5, and 7.5 years was 92%, 88%, 70%, and 56%, respectively. One patient underwent reoperation for recurrent PVE 8 months after operation. CONCLUSIONS: Radical debridement of infected prosthetic material and tissue, and allograft aortic root and ascending aorta replacement, combined with intravenous antibiotic therapy, appears to achieve a low hospital mortality and a high degree of freedom from recurrent infection for patients with PVE after AVR and ascending aortic replacement.     

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.     

Replacement of the aortic root for acute prosthetic valve endocarditis: prosthetic composite versus aortic allograft root replacement

OBJECTIVE: Aortic root replacement for prosthetic aortic valve endocarditis with accompanying destruction of the aortic root is a well-established surgical intervention. However, there is still no consensus whether prosthetic material or allogeneic material should be used. Here we report on our experience with prosthetic composite and aortic allograft root replacement in such patients during a 10-year interval. METHODS: From 1991 through 2001, 29 patients with prosthetic aortic valve endocarditis combined with aortic root destruction underwent reoperation at our institution. Sixteen patients received aortic root replacement with a cryopreserved aortic root allograft (group A) and 13 with a prosthetic composite graft (group B). The interval between the initial operation and reoperation was 29 months (range, 5-168 months) in group A and 55 months (range, 7-248 months) in group B. RESULTS: Hospital mortality was 18.5% (n = 5 patients, 3 in group A and 2 in group B). Median follow-up was 21 months (range, 1-48 months) for group A and 34 months (range, 1-152 months) for group B (P >.2). Survival at 1 and 5 years was 81% +/- 10% and 81% +/- 10% in group A and 85% +/- 10% and 85% +/- 10% in group B, respectively. No patient underwent reoperation for recurrent prosthetic aortic valve endocarditis. CONCLUSIONS: Our results indicate that excellent long-term results can be achieved regardless of the material used for aortic root replacement in patients with prosthetic aortic valve endocarditis.     

Surgical treatment of paravalvular abscess: long-term results.

OBJECTIVE: To examine the outcomes of surgery for active infective endocarditis with paravalvular abscess. METHODS: Paravalvular abscess was defined as infective necrosis of the valve annulus that required patch reconstruction before implanting a new valve. Of 383 patients with active infective endocarditis who underwent surgical treatment, 135 (35%) had paravalvular abscess. Patients' mean age was 51+/-16 years and 68% were men. The infected valve was native in 69 patients and prosthetic in 66. The abscess involved the aortic annulus in 73 patients, the mitral annulus in 27, the aortic and mitral annuluses in 33, and the aortic and tricuspid and/or pulmonary annuluses in 2. Surgery consisted of radical resection of the abscess, reconstruction of the annulus with patches and valve replacement. Mean follow-up was 6.2+/-5.2 years and complete. RESULTS: There were 21 (15.5%) operative deaths. Preoperative shock and abscess in the aortic and mitral annuluses were independent predictors of operative death. There were 34 (25%) late deaths. Survival at 15 years was 43+/-6% for all patients, 50+/-8% for native valve endocarditis and 35+/-9% for prosthetic (p=0.41). Age by increments of 5 years and recurrent endocarditis were independent predictors of late death. There were 16 episodes of recurrent endocarditis in 15 patients, and the freedom from recurrent endocarditis was 82+/-4% at 15 years. Fifteen reoperations were performed in 14 patients. Freedom from reoperation was 72+/-9% at 15 years. CONCLUSIONS: Surgery for active endocarditis with paravalvular abscess was associated with high operative mortality, particularly in patients in shock and abscess of both mitral and aortic annuluses. Long-term survival was adversely affected by age and recurrent bouts of endocarditis.     

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).     

Aortic root replacement with cryopreserved allograft for prosthetic valve endocarditis

BACKGROUND Our strategy has been to treat aortic prosthetic valve endocarditis (PVE) with radical debridement of infected tissue and aortic root replacement with a cryopreserved aortic allograft. This study examines the effectiveness of this strategy on hospital mortality and morbidity, recurrent endocarditis, and survival. METHODS: From 1988 through 2000, 103 patients with aortic PVE underwent root replacement with a cryopreserved aortic allograft. Abscesses were present in 78%, and aortoventricular discontinuity was present in 40%. Thirty-two patients had at least one previous operation for endocarditis. In 23 patients with a history of native valve endocarditis, the allograft was implanted after one episode (17 patients), two episodes (5 patients), or three episodes of PVE (1 patient). In the 80 patients without a history of native valve endocarditis, the allograft was placed after one previous aortic valve replacement (57 patients), two (19), or three (4) previous aortic valve replacements. Among the 92 patients with positive cultures, 52 had staphylococcal organisms, 20 had streptococcal, 6 had fungal, 4 had gram-negative, and 6 had enterococcal organisms. Mean follow-up was 4.3 +/- 2.9 years. RESULTS: Hospital mortality was 3.9%. Permanent pacemakers were required in 31 patients. Survival at 1 year, 2 years, 5 years, and 10 years was 90%, 86%, 73%, and 56%, respectively, with a risk of 5.3% per year after 6 months. Four patients underwent reoperation for recurrent PVE of the allograft (95% freedom from recurrent PVE at > or = 2 years). Risk of recurrent PVE peaked at 9 months and then declined to a low level by 18 months. CONCLUSIONS: A strategy of radical debridement and aortic root replacement with a cryopreserved aortic allograft for aortic PVE is safe, effective, and recommended.     

Early mechanical failures of the Hancock pericardial xenograft

From August 1981 to July 1984, a total of 97 Hancock pericardial xenografts were implanted in 84 patients, whose ages ranged from 13 to 75 years (mean 55.7 +/- 13). Mitral value replacement was performed in 17, aortic valve replacement in 54, and mitral-aortic valve replacement in 13. Operative survivors were reevaluated from July to September 1985. Cumulative duration of follow-up is 167 patient-years (range 0.5 to 4.1 years), and follow-up is 99% complete. The overall late mortality (at 4 years) is 3.6% +/- 1.4% per patient year, and the actuarial survival rate is 95.4% +/- 3% for aortic valve replacement, 74.7% +/- 16.5% for mitral valve replacement, and 67.1% +/- 20.7% for mitral-aortic valve replacement. One patient sustained a thromboembolic event after mitral valve replacement, but no such complications occurred after aortic or mitral-aortic valve replacement. Actuarial freedom from embolism at 4 years is 100% for aortic and mitral-aortic valve replacement and 93.3% +/- 6.4% for mitral valve replacement. Reoperation for Hancock pericardial xenograft dysfunction was performed in seven patients (five aortic and two mitral-aortic). In the aortic valve replacement group the causes were endocarditis in one, paravalvular leak in one, and primary tissue failure in three; all survived reoperation. The two patients with mitral-aortic valve replacement required reoperation because of primary tissue failure of both Hancock pericardial xenografts, and one died. All values explanted because of primary tissue failure showed commissural tears causing severe prosthetic regurgitation. Calcium deposits were severe in one and mild but unrelated to the cusp rupture in another. Collagen disarray was seen only at the site of the tears, whereas the collagen structure was well preserved in the intact parts of the cusps. Four patients with aortic valve replacement and one with mitral valve replacement show evidence of Hancock pericardial xenograft failure and are awaiting reoperation. The actuarial freedom from primary tissue failure at 4 years is 74.3% +/- 9.8% for aortic and 78.9% +/- 13.2% for mitral Hancock pericardial xenografts. At medium-term follow-up, the Hancock pericardial xenograft has shown poor durability and an extremely high rate of early mechanical failure, especially in the aortic position. These observations suggest the need for a close follow-up of Hancock pericardial xenograft recipients and possibly elective reoperation in asymptomatic patients with clinical evidence of prosthetic failure. These results have led us to discontinue the clinical use of this pericardial xenograft.     

Stentless full root bioprosthesis in surgery for complex aortic valve-ascending aortic disease: a single center experience of over 300 patients.

OBJECTIVE: The technically demanding full root aortic valve replacement necessitating coronary ostia reimplantation apparently leads to hesitation by some surgeons despite the superior hemodynamics and excellent long-term clinical performances of the stentless xenografts. Clinical data of stentless full root replacements was retrospectively analyzed in this perspective for validation. METHODS: From November 1999 to March 2007, 317 adult patients (male: 196, female, 121) underwent modified Bio-Bentall procedure using the Medtronic Freestyle xenograft as a full root replacement. Two hundred and three patients received an isolated root replacement or a root and ascending aortic replacement (ARR). In 114 patients a variety of concomitant procedures including coronary artery bypass grafting (n=32), mitral valve repair (n=11) and aortic arch replacement (n=36) were performed. (ARR+). RESULTS: Mean patient age was 70.3+/-10.2 years (range 17-94 years), 97 patients were 75 and older at time of procedure. Mean operative time for the ARR was 190+/-57 min with a clamp time of 88+/-27 min. Mean operative time for ARR+ group was 282+/-93 min with an average clamp time of 110+/-32 min. Overall operative mortality was 7.9% (25/317), for ARR it was 5.4% (11/203). Mean ICU stay was 4.9+/-8.1 days, mean hospital stay being 9.8+/-8.1 days. Necessity for bailout bypass surgery among patients with ARR was low at 1.5% (3/203) comparable to stented xenograft implantations. Echocardiography demonstrated excellent clinical results with low transvalvular gradients especially when a single suture inflow anastomosis technique was used. CONCLUSIONS: Full root stentless valve implantation preserving porcine root integrity is a valuable option in aortic valve/ascending aorta surgery. Though technically a more challenging operation, it does not lead to increased perioperative morbidity and mortality and can be beneficial mainly for elderly patients with small aortic roots with or without aortic root pathology.     

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.     

The St. Jude "Silzone" valve: midterm results in treatment of active endocarditis

BACKGROUND: The Silzone-coated St. Jude Medical valve (SJM "Silzone" valve), developed to reduce prosthetic valve endocarditis (PVE), was recalled by SJM due to a higher rate of paravalvular leaks. The aim of this study was to determine the efficacy of the SJM "Silzone" valve in avoiding PVE and to evaluate the frequency of paravalvular leaks, when the valve was used exclusively for active bacterial endocarditis. METHODS: From January 1998 to December 1999, the SJM "Silzone" valve was implanted in 40 consecutive patients with active endocarditis (20 aortic, 14 mitral, and 6 both valves). Late transesophageal echocardiography was performed in 87% of survivors, and transthoracic echocardiography in the remaining 13%. Follow-up was 100%. RESULTS: Hospital mortality was 17.5%. Early PVE occurred in 2 of 40 patients (5%). There were two late deaths without signs of recurrent PVE. A hemodynamic relevant paravalvular leak necessitating reoperation was seen in 2 patients within 6 months after operation. The rate of a minor paravalvular leak was 13% (4 of 31 patients). CONCLUSIONS: The SJM "Silzone" valve when implanted for active bacterial endocarditis does not give better results than other mechanical prostheses with regard to early recurrence of endocarditis. The rate of a hemodynamic relevant paravalvular leak requiring reoperation seems rather high during the early postoperative period, whereas the occurrence of minor paravalvular leaks is comparable with that of other mechanical prostheses. Routine observation, recommended for all patients with mechanical heart valves, is also sufficient for patients with the SJM "Silzone" valve.     

Evolution of allograft aortic valve replacement over 13 years: results of 275 procedures.

OBJECTIVE: We describe our center's experience with the use of allografts for aortic valve or root replacement, illustrating the impact on outcome of the changes made in surgical and preservation techniques. METHODS: Between 4/1987 and 1/2001 275 allografts were used in 267 consecutive patients to replace the aortic valve or root. All patients were prospectively followed over time. Mean patient age was 46 years (SD 16; range 0.06-83), male/female ratio was 201/74. Prior cardiac operations took place in 73 patients; 49 patients presented with active endocarditis. Pre-operative NYHA-class was III in 51%. Initially, the subcoronary technique was used (SC; N=95) while in recent years root replacement (ARR; N=180) became the technique of choice. Seven fresh (two pulmonary and five aortic) and 268 cryopreserved (four pulmonary and 264 aortic; 35 glycerol and 233 DMSO) allografts were implanted. Concomitant procedures took place in 133 (48%). RESULTS: Operative mortality was 5.5% (N=15) and during follow-up (99% complete) 29 more patients died. Overall cumulative survival was 73% (95% CI 65-81%) at 9 years postoperative and significantly better for SC compared to ARR patients (P=0.005). Freedom from allograft-related reoperation (N=34) was 77% (95% CI 69-85) at 9 years, and worse in the SC compared to ARR group due to increased early technical failure (P=0.03). Freedom from reoperation for structural valve deterioration (SVD; N=22) was 81% (95% CI 73-89) at 9 years and did not differ between SC and ARR (P=0.51). Independent predictors of degenerative SVD were younger patient age (HR 0.93 with age as continuous variable; 95% CI 0.90-0.97), older donor age (HR 1.06 with age as a continuous variable; 95% CI 1.00-1.11), larger allograft diameter (HR 1.38; 95% CI 1.11-1.71) and the use of pulmonary allografts (HR 10.72; 95% CI 3.88-29.63). Calculated median time to reoperation for structural valve deterioration ranged from 23 years in a 65-year-old patient to 12 years in a 25-year-old. CONCLUSIONS: Aortic valve replacement with allografts yields adequate midterm results. Although important changes have been made over the years to improve durability, allografts still have a limited life span especially in young patients.     

Pulmonary homograft: should it be used in the aortic position?

OBJECTIVE: Retrospective analysis was performed to determine the suitability of pulmonary homograft as an aortic valve substitute. METHODS: From January 1994 through June 1999, 147 patients (mean age, 32.2 +/- 17.3 years) underwent aortic valve replacement with either an aortic homograft (group 1: n = 103, 25 fresh antibiotic preserved and 78 cryopreserved) or a pulmonary homograft (group 2: n = 44, 11 antibiotic preserved and 33 cryopreserved). In group 1 a scalloped subcoronary technique was used in 64 patients, and a root replacement technique was used in 39 patients. In group 2 the scalloped subcoronary technique was used in 34 patients, and the root replacement technique was used in 10 patients. RESULTS: There were 131 operative survivors (group 1 = 91; group 2 = 40). Follow-up ranged from 2 to 62 months. In group 1 none of the patients had significant aortic regurgitation during the hospital stay. Three patients (all having undergone the scalloped subcoronary technique) had moderate aortic regurgitation after 6 to 32 months. In group 2, 10 patients (9 having undergone the scalloped subcoronary technique and 1 having undergone the root replacement technique) developed significant regurgitation: 2 intraoperatively, 5 in the early postoperative period before discharge from the hospital, and 3 during late follow-up 6 to 12 months postoperatively. Among the various risk factors analyzed for overall homograft failure, use of a pulmonary homograft was the single independent predictor of valve failure (odds ratio, 8.6; 95% confidence interval, 1.9-39; P =.006). CONCLUSION: Pulmonary homograft, when inserted by means of a scalloped subcoronary technique, is not a suitable aortic valve substitute.     

Homograft replacement of the mitral valve in young recipients: mid-term results.

OBJECTIVE: Mitral homograft (MH) can represent an interesting alternative for valve replacement in the young. However, concerns have been expressed about the durability of valve allografts in children. We report our experience with MH replacement in young patients. METHODS: From 1993 to 1997, 13 young patients aged 3-25 years (mean 15+/-6 years) underwent total mitral valve (MV) replacement with a cryopreserved homograft (CH). All but one had previously undergone one or more cardiac operations. The indications were rheumatic disease (6), acute and subacute endocarditis (2), congenital heart disease (4), and systemic lupus endocarditis (1). RESULTS: No in hospital deaths are reported. Discharge echocardiogram showed a well-functioning MH in all but one patient. One patient was lost to follow-up. Follow-up ranged from 0.7 to 6.6 years (4.1+/-2.2). On follow-up two patients were doing well. Two patients died without reoperation and both had MV stenosis. Seven patients (54%) required reoperation: mean delay 4.17 years (0.7-7). In all cases, thickening, shrinking and calcification of the allograft were present. None of these seven had contributive histopathologic changes. One patient presenting recurrent MV insufficiency will require a reoperation. CONCLUSION: MV homograft is a safe and reproducible technique, but does not provide durable results and should not be used in young patients.     

Replacing the ascending aorta and aortic valve for acute prosthetic valve endocarditis: is using prosthetic material contraindicated?

BACKGROUND: The use of prosthetic material (rather than a homograft) for ascending aorta/aortic valve replacement (Bentall procedure) in cases of acute prosthetic valve endocarditis is controversial. We report favorable results using this technique almost exclusively (a homograft was used in only 3 patients with hematological problems) during a 12-year interval. METHODS: Twenty-eight patients (55 +/- 14 years; 22 male) underwent a Bentall procedure for acute prosthetic valve endocarditis between 1988 and 2000. Twenty-five patients had undergone previous aortic valve replacement (1 with concomitant mitral valve replacement, 4 with coronary artery bypass grafting), and 3 had had a previous Bentall operation. The median interval between initial surgery and reoperation was 13 months (range, 1 to 106). Sixty-eight percent of operations were urgent or emergencies. Ninety-three percent of patients had significant aortic regurgitation; complete annuloaortic dehiscence occurred in 71%, and in 57%, an abscess was found. Causative organisms were identified in 25 of 28 patients: Staphylococcus epidermidis (9), Staphylococcus aureus (7), Streptococcus viridans (6), Pseudomonas (2), and Legionella (1). RESULTS: Twenty-three patients had mechanical and 5 had biological valves implanted during the Bentall procedure. Hypothermic circulatory arrest was used in 64%. Hospital mortality was 11%: there was one intraoperative death, and two before discharge (one cardiac, one sepsis). Eighty-nine percent survived without stroke. During follow-up (median, 44.5 months; complete in 92%), 1 patient died of recurrent endocarditis at 4 months. CONCLUSIONS: These results indicate that prosthetic root replacement may be superior to use of a homograft for acute aortic prosthetic valve endocarditis, with only a 4% incidence of recurrent endocarditis and reoperation.     

Surgical management of acute aortic root endocarditis with viable homograft: 13-year experience.

OBJECTIVE: Cryopreserved homograft valves have been used for acute infective aortic root endocarditis with great success but it is compounded by its availability in all sizes. The long-term clinical results of geometric mismatched homografts are not well defined and addressed. METHODS: Over a 15-year period (April 1986-June 2001), 816 patients presented with active infective endocarditis. One hundred and eighty-two of the patients aged between 9 and 78 years (mean: 51.0 +/- 1.13 years) consisting of 142 males and 40 females received homograft aortic valves. One hundred and ten patients were in NYHA functional class III and 72 in class IV and in cardiogenic shock. Of the patients, 2.7% suffered from septic embolism. One hundred and twenty-four (68.1%) patients presented with periannular abscesses and 58 (31.9%) with no abscess while 107 native valve (NVE) and 75 prosthetic valve (PVE) endocarditis were diagnosed preoperatively by transesophageal echocardiography (TEE) and confirmed intraoperatively. Freehand subcoronary implantation (FSCI) was used in 106 patients and root replacement in 76 patients. RESULTS: The operative death was 8.5% and for patients in NYHA functional class IV and in cardiogenic shock was 14.5%. Late mortality rate was 7.9%. Patient survival after discharge from hospital at 1 year was 97% and at 10 years was 91%, respectively. Thirty-one (22.1%) patients underwent reoperation after 1.7 years (mean) with two deaths (6.4%). Early (< or = 60 days) and late reinfection rate was 2.7 and 3.6%, respectively. Freedom from reoperation for matched and undersized homografts at 10-13 years was 85 and 55%, respectively. The univariate model identified undersized homograft (P=0.002), FSCI (P=0.09) and reinfection (P=0.0001) as independent risk factors for developing early and late valve dysfunction resulting in reoperation and homograft explant. CONCLUSION: Early aggressive valve replacement with homograft for active infective aortic root endocarditis with periannular abscesses is more successful than delayed last resort surgery. Homografts exhibit excellent clinical performance and durability with a low rate of reinfection, if properly inserted. Undersized homograft is an incremental risk factor for early and late reoperation.     

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.     

Repair of the truncal valve and associated interrupted arch in neonates with truncus arteriosus

OBJECTIVE: Truncal valve regurgitation and interrupted aortic arch have frequently been identified as risk factors in the repair of truncus arteriosus. We wished to examine these factors in the current era including the impact of truncal valve repair. METHODS: Between January 1992 and August 1998, 50 patients underwent surgical repair of truncus arteriosus. Their ages ranged from 2 days to 6 months (median, 2 weeks). Nine patients had associated interrupted aortic arch. Of the 14 patients (28%) in whom truncal valve regurgitation was diagnosed preoperatively, 5 had mild regurgitation, 5 had moderate regurgitation, and 4 had severe regurgitation. Five underwent truncal valve repair and 1 underwent homograft replacement of the truncal valve with coronary reimplantation. RESULTS: The actuarial survival was 96% at 30 days, 1 year, and 3 years. There were no deaths in patients with associated interrupted aortic arch. The 2 deaths in the series occurred in patients with truncal valve regurgitation, neither of whom underwent repair. Postoperative transthoracic echocardiography in patients who underwent valve repair showed minimal residual valvular regurgitation. None of the patients has required reoperation because of truncal valve problems or aortic arch stenosis at a median follow-up of 23 months (range, 1-60 months). Conduit replacement has been done in 17 patients (34%) after a mean duration of 2 years. The freedom from reoperation for those who had an aortic homograft was 4 years and for those who had a pulmonary homograft was 3 years. CONCLUSION: Despite the magnitude of the operation, excellent results can be achieved in complex forms of truncus arteriosus. In the current era interrupted aortic arch is no longer a risk factor for repair of truncus. Aggressive application of truncal valvuloplasty methods should neutralize the traditional risk factor of truncal valve regurgitation.