Tricuspid valve replacement after cardiac transplantation.

Tricuspid regurgitation, a fairly common finding after cardiac transplantation, is generally mild or moderate, and is not clinically significant. The etiology of tricuspid regurgitation is not entirely understood, and experience with valve replacement after cardiac transplantation is limited. We describe a case of progressively severe tricuspid regurgitation ultimately requiring tricuspid valve replacement. At operation, the ruptured chordae of the posterior part of anterior and septal leaflet with resulting partially flail leaflets were found. Examination of the papillary muscle showed origins of several of the ruptured chordae. Damage to the tricuspid subvalvular apparatus at endomyocardial biopsy appeared to be a possible cause. A 31-mm Carpentier-Edwards porcine valve was implanted. This was because replacement with a mechanical prosthesis would prevent future right-side heart catheterization and endomyocardial biopsy and in valve repair, the patient remains exposed to the risk of the recurrence of chordal rupture. We discuss proposed causes and choices in surgical technique.     

Tricuspid valve replacement after cardiac transplantation

BACKGROUND: Tricuspid regurgitation (TR) occurs commonly in transplanted hearts. Although theoretically attractive, tricuspid valve replacement (TVR) has not been widely investigated as a possible therapy in post-transplant patients. The purpose of this study was to determine the safety of TVR in heart transplant patients and its effects on measurable clinical endpoints. METHODS: We acquired data by both retrospective chart review and prospective data collection in all patients who underwent TVR after cardiac transplantation. RESULTS: Nine patients were identified and followed for a period of six months. The age of patients at time of TVR was 62 +/- 6.1 yr and their average time since transplantation was 12 +/- 3.2 yr. Most patients demonstrated a reduction in their furosemide dose (105 +/- 63 mg/d pre-TVR vs. 67.5 +/- 65 mg/d post-TVR, p = 0.001) with a reduction in serum creatinine levels (188 +/- 72 micromol/L pre-TVR vs. 143 +/- 42 micromol/L post-TVR, p = 0.06). Additionally, we found a significant improvement in albumin values (32 +/- 5 g/L pre-TVR vs. 42 +/- 3 g/L post-TVR, p = 0.002) as well as an improvement in total bilirubin (35 +/- 18 micromol/L pre-TVR vs. 18 +/- 5 micromol/L post-TVR, p = 0.05). There was only one death in our series, in the only patient with known severe graft atherosclerosis. CONCLUSIONS: TVR appears to be a safe procedure in patients without severe graft atherosclerosis with improvements in serum creatinine, albumin and total bilirubin values, in addition to a reduction in furosemide dose. This may reflect improved forward flow, improved symptomatology from TR as well as possible beneficial effects on nutritional status.     

Midterm results after aortic valve replacement with the autologous tissue cardiac valve.

OBJECTIVE: To assess midterm results after aortic valve replacement (AVR) with an autologous tissue cardiac valve (ATCV). This new technique was developed to construct a tissue prosthesis for AVR using the patients pericardium, harvested at the time of operation with negligible effect on operating time. METHODS: Briefly, glutaraldehyde tanned pericardium is mounted on a stent requiring no suturing. Between March 1994 and December 1996, 87 patients, 44/43 M/F and aged 70 +/- 6 years had AVR for aortic stenosis (80%), aortic insufficiency (6%) and combined lesions (14%), one patient suffered from endocarditis. Additional coronary artery bypass was done in 25%, aortic root enlargement in 7%. Aortic cross clamp and cardiopulmonary bypass times were 69 +/- 21 and 93 +/- 29 min. All patients were followed by clinical examination and color flow Doppler echocardiography in 3-12 months interval. Follow up was 99% complete. RESULTS: There were five perioperative deaths (6%), none of them valve related. Eighty-one patients were followed up to a period of 52 months (mean interval 37.5 +/- 1.3 months), one patient was lost for follow up. Overall survival was 86, 81, 79 and 71% at 12, 24, 36 and 48 months, respectively. There were 14 late deaths with eight (10%) valve related (four cerebral deaths, four sudden deaths). Sixteen patients (20%) had to be re-operated due to severe valve incompetence. Freedom from reoperation was 98, 97, 90 and 63% at 12, 24, 36, and 48 months, respectively. Valve incompetence occurred suddenly, without previous signs in the follow-up examinations. Selection and preparation of the pericardium, the way of fixation of the tissue--brief immersion in glutaraldehyde--and engineering problems might be responsible for this disastrous outcome. CONCLUSION: Due to these results we must state, that the ATCV did not fulfill our expectations and presently we can not recommend it as an aortic valve substitute.     

Mitral valve replacement six years after cardiac transplantation

A 33-year-old man found to have increasing mitral regurgitation and decreasing exercise tolerance 6 years after cardiac transplantation received a mitral bioprosthesis. For 8 months he has been without complications from the valve replacement and is clinically and hemodynamically considerably improved.     

Aortic valve replacement in cardiac ochronosis.

Two patients with generalized ochronosis developed cardiovascular symptoms related to cardiac ochronosis with aortic valvular stenosis. One patient with a transvalvular pressure gradient of 150 mm Hg underwent emergency aortic valve replacement. The other patient with a transvalvular pressure gradient of 96 mm Hg underwent successful elective aortic valve replacement. Cardiac ochronosis is a rare disease that might be encountered, with the typical signs, during an elective, planned cardiac operation. The most frequent presenting feature of this disease seems to be aortic valvular stenosis.     

517例瓣膜置换术后发生肺不张的危险因素分析

目的分析瓣膜置换术后肺不张的危险因素,为临床选择治疗方法和评估预后提供依据。方法将我院1998年1月至2005年10月完成的517例瓣膜置换术患者按有无肺不张分成两组,进行单因素分析和多因素Logistic回归分析。结果全组有肺不张31例,单因素显著性分析发现年龄、吸烟史、左心房直径、术前肺动脉高压、体外循环时间、主动脉阻断时间、胸膜完整、使用膜肺以及应用药物和长期应用呼吸机有相关性;多因素Logistic回归分析结果显示高龄、体外循环时间、联合瓣膜病等是独立的相关危险因素。结论瓣摸置换术后肺不张与多种因素有关,临床应引起高度重视。     

Transcatheter aortic valve replacement 24 years after cardiac transplantation

As patient survival after cardiac transplantation has improved over the course of the last several decades, clinicians are now faced with late complications. This includes aortic stenosis which, traditionally, has been treated with reoperative sternotomy and aortic valve replacement. Transcather aortic valve replacement (TAVR) offers a minimally invasive alternative in this high-risk population. A small but growing number of cases of TAVR after heart transplantation in high-risk patients have been reported in the last 10 years; we now present a case of aortic valve replacement via a transcatheter approach 24 years after cardiac transplantation.     

Late results after left-sided cardiac valve replacement in children

Selection of types of cardiac valve substitutes for children remains controversial. Between 1976 and 1984, 166 children, 15 years of age or younger, underwent aortic (N = 53) or mitral valve replacement (N = 90) or both (N = 23). Biological prostheses were used in 84 patients and mechanical prostheses in 71; both a mitral bioprosthesis and an aortic mechanical valve were used in 11 patients. The overall early mortality was 9%. Mean follow-up intervals were 4.1 years for the bioprosthesis group, 3.3 years for the mechanical valve group, and 3.5 years for the group receiving both. The 7 year survival rates (+/- standard error) were 63% +/- 6% in the bioprosthesis group and 70% +/- 7% in the mechanical valve group (p = NS). After aortic valve replacement the 7 year survival rates were 66% +/- 14% (bioprosthesis group) and 77% +/- 9% (mechanical valve group) (p = NS); after mitral valve replacement the rates were 65% +/- 7% (bioprosthesis group) and 54% +/- 17% (mechanical valve group) (p = NS). The incidence of thromboembolic events was 0.6% +/- 0.4% per patient-year in the bioprosthesis group (none after aortic valve replacement, 0.8% +/- 0.6% per patient-year after mitral valve replacement) and 1.4% +/- 0.8% per patient-year in the mechanical valve group (0.7% +/- 0.7% per patient-year after aortic valve replacement, 4.0% +/- 2.8% per patient-year after mitral valve replacement) (p = NS). The linearized rates of reoperation were 10.4% +/- 1.8% per patient-year (bioprosthesis group) and 2.3% +/- 1.0% per patient-year (mechanical valve group) (p less than 0.001). The 7 year probability rates of freedom from all valve-related complications were 43% +/- 6% in the bioprosthesis group and 86% +/- 4% in the mechanical valve group (p less than 0.001). In the aortic position, a mechanical adult-sized prosthesis can always be implanted, and satisfactory long-term results can be anticipated. In the systemic atrioventricular position, the results are less than satisfactory with either type of prosthesis; every effort should be made to preserve the natural valve of the child.     

Bioprostheses for cardiac valve replacement

Biologic tissue has been used successfully for cardiac valve substitutes since the introduction of glutaraldehyde preservation in 1969. Assessment of the clinical performance of prosthetic valves requires consideration of thromboembolism, anticoagulant-related hemorrhage, prosthetic valve endocarditis, periprosthetic leak and prosthesis failure. Two methods of assessment of valve performance, linearized occurrence rates and multiple decrement analysis of valve-related complications, are illustrated in evaluation of previous and new-generation Carpentier-Edwards porcine bioprostheses. The standard valve has a valve-related complication rate of 2.9% per patient-year over 5 years, while the rate for the new-generation supra-annular prosthesis is 4.3% per patient-year in the 2-year interval. Thromboembolism has been 1.6% and 1.7% per patient-year, respectively, for the previous and new-generation prostheses. Primary tissue failure has occurred only in the standard prosthesis, 0.6% per patient-year. The freedom from all valve-related complications is 93.1% at 2 years and 87.5% at 6 years with the standard valve and 95.1% at 2 years with the new-generation prosthesis. Standardized assessment of prosthetic performance should provide physicians and surgeons with the knowledge to optimize patient management. The new-generation biologic prostheses with improved preservation should reduce calcification and fatigue lesions. Tissue valves have afforded patients an excellent quality of life with a low incidence of valve-related complications.     

Survival and valve failure after aortic valve replacement.

A prospective evaluation of 412 consecutive patients undergoing isolated aortic valve replacement between January 1982 and December 1985 was performed in an attempt to identify the determinants of survival and valve failure. A variety of valves were inserted to permit a prospective evaluation of alternative valves including: Bj?rk-Shiley mechanical (n = 37), Ionescu-Shiley pericardial (n = 261), Hancock pericardial (n = 78), and Carpentier-Edwards porcine (n = 36). Thirteen patients died in the hospital (3.2%) and 47 patients died in the follow-up period producing an actuarial survival of 81% +/- 3% at 48 months. Survival was independently predicted by advancing age, preoperative New York Heart Association functional class, and the presence of endocarditis (p less than 0.05 by Cox regression analysis). The majority of patients were symptomatically improved (New York Heart Association class I or II: 21% preoperative, 88% postoperative). Freedom from structural valve dysfunction, prosthetic valve endocarditis, and reoperation for valve-related complications were 95% +/- 2%, 95% +/- 2%, and 92% +/- 2% at 48 months, respectively. These valve-related complications occurred more frequently in younger patients and in those with a Hancock pericardial valve (freedom from structural valve dysfunction, 89% +/- 5%; prosthetic valve endocarditis, 84% +/- 9%; reoperation, 78% +/- 10%; p less than 0.05 by Cox regression). Freedom from thromboembolism was 88% +/- 2% at 48 months; it was significantly lower in patients with a preoperative thromboembolic event and was not influenced by the type of prosthesis inserted. Freedom from anticoagulant-related hemorrhage was 85% +/- 8% at 48 months and was not influenced by any preoperative factors.(ABSTRACT TRUNCATED AT 250 WORDS)     

Mitral valve replacement in patients after aortic valve replacement

BACKGROUND: Mitral valve replacement in patients who previously had undergone aortic valve replacement is a technical challenge. The rigid aortic prosthesis limits visualization of the anterior mitral annulus and placement of sutures. METHODS: Reoperative mitral valve replacement was performed in five patients after aortic valve replacement. Two patients underwent resternotomy to allow verification of normal aortic prosthetic valve function. Anterolateral right thoracotomy was used for reentry in the remaining three patients. Exposure of the anterior mitral annulus was accomplished by initial traction on the intact anterior leaflet, with resection of this leaflet only after placement of sutures. RESULTS: All patients survived the surgical procedure and are well 2 to 30 months after operation. In one patient it was impossible to open one cusp of the mitral prosthesis, nor was it possible to rotate the valve. The valve was reimplanted, but sutures were tied only after testing for full free cusp motion. CONCLUSIONS: When appropriate, right thoracotomy incision offers excellent exposure of the mitral valve with minimal dissection. Placement of sutures along the anterior portion of the annulus is facilitated by traction downwards on the anterior leaflet. Full range of motion of the prosthetic cusps should be verified before tying the sutures.     

Partial upper re-sternotomy for aortic valve replacement or re-replacement after previous cardiac surgery.

OBJECTIVE: We developed techniques for 'inverted T' partial upper re-sternotomy for aortic valve replacement (AVR) or re-replacement (AVreR) after previous cardiac surgery. We previously reported on decreased blood loss, transfusion requirements and total operative duration when compared to conventional full re-sternotomy. This report updates our series, one of the few to document a substantial benefit from a 'minimally-invasive' approach, refines a number of technical aspects of this new approach and reports follow-up. METHODS: Between November 1996 and December 1999, we performed 34 AVRs or AVreRs after previous cardiac surgery by use of an 'inverted T' partial upper re-sternotomy. There were 25 (74%) men. Median ejection fraction was 54%, range 15-80%. Median age was 72, range 38-93. All were New York Heart Association functional class (NYHA) functional class II or III. Twenty-one (62%) had previous coronary artery bypass grafts (CABG) while 14 (41%) had previous valve surgery. Follow-up was 100% complete for a total of 593 patient months (median 19 months). RESULTS: Twenty-three (66%) underwent AVR of the native aortic valve while 11 (33%) underwent AVreR of a prosthetic aortic valve. There were no intraoperative or valve-related complications, and no conversion to full re-sternotomy was necessary. There were two (5.9%) operative deaths from an arrhythmia on postoperative day 4 and a large stroke during surgery, respectively. Twenty-four (75%) patients were free of major complications. There was no need for reoperation for bleeding and patients required a median of two units of packed red blood cells. Complications included new atrial fibrillation (n=3, 9%), pacemaker implantation (n=3, 9%) and deep sternal wound infection (n=2, 6%). Median lengths of stay in the intensive care unit (ICU) and in the hospital were 1 and 7 days, respectively. There was one (3%) late deep sternal wound infection and 2/32 (6%) late deaths due to congestive heart failure at 22 months and myocardial infarction at 23 months, respectively. CONCLUSIONS: Partial upper re-sternotomy presents a safe and effective alternative approach to AVR and AVreR after previous cardiac surgery, and is associated with low morbidity and mortality.     

左心瓣膜置换术后远期三尖瓣关闭不全的外科治疗

目的探讨左心瓣膜置换术后远期三尖瓣关闭不全(tricuspid incompetence, TI)发生的可能机制、外科治疗方法的选择和结果. 方法 12例风湿性心瓣膜病患者,第1次手术时行二尖瓣和主动脉瓣双瓣膜置换术(DVR)8例,二尖瓣置换术(MVR)4例,同时行DeVega三尖瓣成形术(TVP)3例,因三尖瓣无明显异常未作处理9例.距第1次手术后5～17年,平均10.2年,所有患者发生重度TI,其中8例行三尖瓣置换术(TVR),4例行TVP. 结果早期死亡2例,病死率16.7%.随访10例,随访时间4～36个月,平均18.2±7.8个月.6例行TVR患者术后心功能恢复良好,4例TVP患者出现轻度TI,6个月后,其中2例TI有逐渐加重的趋势. 结论左心瓣膜置换术后远期TI可能与持续肺动脉高压、右心室不可逆损害以及左心功能的恢复情况有关.重度TI行TVR的疗效可靠,而一些TVP患者TI有逐渐加重的趋势.