Mitral valve replacement in children under 3 years of age.

OBJECTIVE: This study was undertaken to review our experience of mitral valve replacement in children under 3 years of age. METHODS: Between January 1990 and May 2004, 18 patients under 3 years of age underwent a total of 20 mitral valve replacements using a bileaflet mechanical prosthetic valve. There were 9 males and 11 females. The age at surgery ranged from 3 months to 3 (mean=1.02 +/- 0.72) years and body weight varied between 3.4 and 13.2 (mean=7.08 +/- 2.74) kg. RESULTS: There were 4 early and 2 late deaths, and these occurred in severe cases aged less than 1 year of age. Re-replacement of mitral valve was required in 3 patients (valve thrombosis in 2 and pannus formation in 1). Orifice size of the implanted prosthesis (OS) as compared with the predicted normal size of the mitral valve (NS) was well correlated with maximum transprosthetic flow velocity estimated by Doppler echocardiography. In this study, the OS/NS>0.65 was maintained in all patients, and none required re-replacement because of prosthesis-patient mismatch. CONCLUSION: Patients less than 1 year of age had significant mortality and morbidity. The results were satisfactory in the remainder (1-3 years). During this follow-up period, none required re-replacement due to somatic growth, but it will be an unavoidable problem in the future. The OS/NS, which can be checked with a regular physical examination, may serve as a guide to determine the most appropriate timing for the second surgery.     

Mitral valve replacement in patients younger than 6 years of age

We present our experience in mitral valve replacement (including left-sided tricuspid valve in corrected transposition) in patients younger than 6 years of age. The long term results were examined with special focus on re-replacement of the valve. Between 1974 and 1995, we performed mitral valve replacement in 14 patients younger than 6 years of age, with no operative mortality. There were 3 late deaths, caused by endocarditis, valve thrombosis, and congestive heart failure, respectively. The five-year-survival rate after primary replacement was 85%, and the ten-year-survival rate was 75%, using Kaplan-Meier analysis. Ten patients (11 occasions) required repeated mitral valve replacements at 2 months to 17 years after the original replacement. The indication for the second or third mitral valve replacement was paravalvular leakage (2 patients), valve thrombosis (1 patient), degeneration in the porcine prosthesis (3 patients), and patient outgrowth of the original small prosthesis (5 patients). Again there was no operative mortality. One patient who suffered from multiple occasions of valve thrombosis died at two years after the second replacement. All patients who had outgrown the prosthetic valve received larger prosthesis at the second replacement than at the primary replacement. The actuarial percentage of freedom from valve-related events at 3 years, 5 years, and at 10 years, was 50%, 37%, and 8%, respectively. Conclusions: Mitral valve replacement in patients younger than 6 years of age can be performed relatively safely, but meticulous follow-up and appropriate decision making for re-replacement is mandatory for the long-term survival of these patients.     

Mitral valve replacement in children

Rheumatic fever leading to advanced valvular heart disease, in adults and children, is still frequently seen in developing countries. In the period 1981-87, 1137 patients underwent open heart surgery for either repair (489 patients), or replacement (639 patients) of defective cardiac valves. The experience with 75 children who underwent mitral valve replacement among this group is reviewed. The aetiology of mitral valve disease was rheumatic in 71, and infective endocarditis in four; 85% of the children were in NYHA functional class III, and 15% in class IV. Seven children had intra-operative findings of rheumatic activity. Pure mitral regurgitation was seen in 41, while mixed mitral valve disease was observed in 34 children. Twenty-seven children underwent mitral valve replacement with Ionescu-Shiley bovine pericardial valves, and 48 with mechanical Bi-leaflet valves. The operative mortality was 9.3%, and the actuarial survival rate, calculated by the Cutler and Ederers method, was 87% at 5 years.     

Mitral valve replacement in patients younger than 6 years of age.

We present our experience in mitral valve replacement (including left-sided tricuspid valve in corrected transposition) in patients younger than 6 years of age. The long term results were examined with special focus on re-replacement of the valve. Between 1974 and 1995, we performed mitral valve replacement in 14 patients younger than 6 years of age, with no operative mortality. There were 3 late deaths, caused by endocarditis, valve thrombosis, and congestive heart failure, respectively. The five-year-survival rate after primary replacement was 85%, and the ten-year-survival rate was 75%, using Kaplan-Meier analysis. Ten patients (11 occasions) required repeated mitral valve replacements at 2 months to 17 years after the original replacement. The indication for the second or third mitral valve replacement was paravalvular leakage (2 patients), valve thrombosis (1 patient), degeneration in the porcine prosthesis (3 patients), and patient outgrowth of the original small prosthesis (5 patients). Again there was no operative mortality. One patient who suffered from multiple occasions of valve thrombosis died at two years after the second replacement. All patients who had outgrown the prosthetic valve received larger prosthesis at the second replacement than at the primary replacement. The actuarial percentage of freedom from valve-related events at 3 years, 5 years, and at 10 years, was 50%, 37%, and 8%, respectively. CONCLUSIONS: Mitral valve replacement in patients younger than 6 years of age can be performed relatively safely, but meticulous follow-up and appropriate decision making for re-replacement is mandatory for the long-term survival of these patients.     

小年龄患儿的二尖瓣置换手术

目的 总结5岁以下二尖瓣病变患儿行二尖瓣置换手术的治疗经验.方法 2008年1月至2011年12月,共12例5岁以下的二尖瓣病变患儿进行二尖瓣置换手术.其中男9例,女3例;年龄4～58个月,平均(26.2±18.1)个月;体质量5.6 ～13.0 kg,平均(9.6±3.8) kg.患儿有中度以上二尖瓣反流或(和)明显的二尖瓣狭窄,均伴有明显的心功能衰竭.3例为二尖瓣成形术后再行二尖瓣置换术.均置入机械瓣膜,9例采用17 ～ 23号主动脉瓣反向置入,3例采用25～27号二尖瓣正向置入.结果 手术死亡1例(8.3％).术后心律失常2例,轻度溶血2例,经治疗均恢复正常.11例生存患儿心功能改善明显,未出现出血和血栓形成等异常情况.结论 严重二尖瓣病变对小年龄儿童的心功能影响极大,尽早手术干预是惟一的选择,二尖瓣置换术是二尖瓣成形手术效果不佳患儿的最后选择.采用型号相对较小的主动脉瓣倒置置入二尖瓣环内,基本解决了机械瓣瓣膜-患者不匹配的问题,但置入小型号机械瓣的患儿再次行二尖瓣置换术的可能较大;小年龄儿童有良好的抗凝依从性,但需加强监测抗凝指标,以防发生出血和栓塞.     

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.     

Mitral-valve replacement in children under 6 years of age.

OBJECTIVE: In patients with congenital mitral-valve disease, reconstructive surgery is the primary goal. However, in cases with severely dysplastic valves or failed repair, mitral-valve replacement (MVR) is the only option. We analyzed, retrospectively, data of 35 patients younger than 6 years of age, who underwent MVR at our institution. METHODS: Between 1974 and 1997, 35 children underwent MVR. The ages ranged from 2.7 months to 5.5 years (mean=1. 9+/-1.7 years) and body weight varied between 3.2 and 16.7 kg (mean=8.2+/-4 kg). The main indication (57%) for valve replacement was severe mitral-valve insufficiency. Eighteen patients (51%) had undergone at least one previous reconstructive operation (mean=1. 46+/-1.86 years) before the MVR. In 29 cases (83%), mechanical prostheses were implanted. Six patients received a bioprosthesis. The size of the prostheses ranged between 14 and 27 mm. RESULTS: The overall hospital mortality was 17.1% (6/35), and decreased from 33 (1974-1985) to 11.5% (1986-1997). Seven children died late. The actuarial survival after 20 years was 51.2+/-13.3%. Eight patients (23%) required 10 reoperations (8.2%/100 patient-years). Freedom from reoperation at 10 years was 50+/-22%. Valve-related complications were thrombo-embolism (n=2; 1.6%/100 patient-years), hemorrhage (n=1; 0.8%/100 patient-years), structural deterioration (n=3; 2.5%/100 patient-years) and non-structural dysfunction (n=3; 2. 5%/100 patient-years). Follow-up is 96% complete, with a total of 122 patient-years (mean=4.2+/-4.7 years). Eighty six percent of the patients are in New York Heart Association (NYHA) class I, 95% have sinus rhythm and 59% do not need medication. All survivors, except for those who received a bioprosthesis, were placed on a regimen of Phenprocoumon (Marcumar((R))), aiming to maintain the International Normalized Ratio (INR) between 2.5 and 3.5. In one third of these children, self-management of oral anticoagulation was performed either by the patients or their parents. CONCLUSIONS: MVR in small children still carries a high risk. In our experience, the long-term results are satisfying. After failed reconstructive surgery, or as a primary procedure, we prefer mechanical prostheses. They are well tolerated and the incidence of anticoagulation-related complications is low.     

Mitral valve replacement in the first 5 years of life

Between 1976 and 1986, 19 children aged 1 month to 5 years underwent replacement of the mitral (systemic atrioventricular) valve. Indications for valve replacement included isolated congenital mitral stenosis (n = 2), valve dysfunction associated with a more complex procedure (n = 15), and failed valvuloplasty (n = 2). Seven different valve types were used; nine were mechanical valves and ten were bioprosthetic valves. There were 6 hospital deaths (32%; 70% confidence limits, 20% to 47%). Among the 13 survivors there were 3 late deaths at a mean of 14 months after operation. The late deaths were unrelated to valve malfunction. Thromboembolic events occurred in 2 patients, both with mechanical valves. One minor bleeding complication occurred among 10 patients on a regimen of Coumadin (crystalline warfarin sodium). Five patients, all with bioprostheses, required a second valve replacement. Indications for reoperation included prosthetic valve regurgitation (n = 1) and calcific stenosis (n = 4). No early or late deaths occurred after second valve replacement. Survival was 51% +/- 12% (standard error) at 112 months after valve replacement. Analysis failed to identify age, weight, sex, previous operation, underlying cardiac lesion, or prosthesis size and type as significant risk factors for mortality. Mechanical valves had a lower reoperation rate compared with bioprostheses. These data suggest that although mitral valve replacement within the first 5 years of life is associated with a high operative and late mortality, satisfactory long-term palliation for many patients can be achieved. Mechanical valves are superior to bioprosthetic valves, and offer the best long-term results.     

Mitral valve replacement 41 years after right pneumonectomy]

Mitral valve replacement was performed successfully on a 68-year-old patient who had undergone right pneumonectomy and thoracoplasty 41 years earlier. Preoperative pulmonary function tests revealed poor results; the forced vital capacity was 950 ml (28.0% of the predicted value) and the forced expiratory volume in 1 second was 750 ml (28.9% of the predicted value). Despite such poor pulmonary function, the patient tolerated the operation well and led uneventful course. Careful perioperative management to prevent pulmonary edema and aggressive postoperative pulmonary toilet to facilitate recovery of the pulmonary function seem important.     

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.     

Mitral valve replacement in children: predictors of long-term outcome

BACKGROUND: Mitral valve replacement (MVR) in children has been associated with a high complication rate. We sought to assess predictors of outcomes in children undergoing MVR. METHODS: A retrospective review of clinical, surgical, and echocardiographic records of patients undergoing MVR was performed. Between 1982 and 2000, 53 children underwent 76 MVR procedures at a median age of 5 years (range, 1 day to 18 years) and weight of 17 kg (range, 3 to 121 kg). Eighteen patients (34%) had more than one MVR. Previous cardiac surgery had been performed in 39 (74%), with 27 (51%) undergoing previous mitral repair. Patients were followed for 9.2 +/- 4.8 (range, 2 to 20) years. RESULTS: There were 14 patient deaths, with 6 patients dying within 30 days, and five transplants (36%). Ten-year freedom from reoperation was 66%. Long-term survivors were older at initial repair (7.0 vs 2.5 years, p = 0.02), with a lower incidence of residual cardiac lesions (3% vs 37%, p < 0.001) and a lower incidence of surgical procedures at the time of MVR (31% vs 63%, p = 0.04). Survivors had better left ventricular function preoperatively (ejection fraction, 68% vs 54%; p = 0.001) and placement of a prosthetic valve within 1 z-score of the echocardiographically measured mitral valve annulus (p = 0.02). CONCLUSIONS: Adverse outcome after MVR is common, particularly in the young child undergoing palliative surgery or requiring additional surgical procedures. Preoperative assessment of mitral valve size and ventricular function is essential for risk stratification of these patients.     

Late results of mitral valve replacement with the Bj?rk-Shiley prosthesis in children under 16 years of age

The late results of isolated mitral valve replacement were evaluated in 37 children under 16 years of age receiving a Bj?rk-Shiley prosthesis for the treatment of rheumatic mitral lesions. Three patients died, one during the operation and the others 2 months postoperatively. Of the latter two, one had a cerebral hemorrhage and the second had septicemia. The survivors were followed up for a mean of 4.7 years (range 2.8 to 8.9 years). After the operation, all patients were placed on a strict anticoagulant regimen with acenocoumarol. The actuarial survival rate was 92% at the end of the follow-up period. Before valve replacement two patients were in New York Heart Association Class I, 15 in Class II, 18 in Class III, and two in Class IV. After treatment 33 were in Class I and one in Class II. No instances of thromboembolism or infective endocarditis were observed in the survivors. Twenty-one patients underwent cardiac catheterization 2 to 7 years after the operation for evaluation of surgical results. The mean pulmonary artery systolic pressure decreased significantly after operation (p = 0.001), and the mean pulmonary artery wedge pressure decreased to normal values (p = 0.001). A mild mean diastolic gradient across the mitral valve at rest was found after the operation (4.9 +/- 2.4 mm Hg). During isometric exercise this gradient increased to 6.5 +/- 4.6 mm Hg. In two patients a discrete paravalvular leak was demonstrated by cineangiography, but the pulmonary wedge pressure was normal in both. The overall results with the Bj?rk-Shiley prosthesis are encouraging in patients in whom reconstructive operations cannot be performed.     

Mitral valve replacement in the pediatric age group- a single institution experience

Background  Mitral valve replacement in pediatric patient is a difficult surgical task, with many intraoperative and post-operative considerations. We conducted this study to evaluate the indications and early results of mitral valve replacement in children. Methods  From January 2003 to July 2008, fifty-four children under the age of fifteen years underwent mitral valve replacement at our institution. All children received a mechanical bi-leaflet or tilting disc prosthetic valve. All of them underwent valve replacement on the basis of preoperative echocardiography and intraoperative assessment of valve pathology. Results  Preoperatively 65% of the children were in New York Heart Association (NYHA) class III and 35% of them were in NYHA class IV. The cause of mitral valve disease was chronic rheumatic valve disease in 97% of cases and congenital in 3% of the cases. In the rheumatic group 66% of them had severe mitral regurgitation as predominant lesion. The mean diameter of the implanted valve was 27.17mm. There was no hospital or 30 day mortality. The mean follow-up period was 3.6 years. One patient died after 2 years from a stuck valve. Two other patients required thrombolysis for stuck valves. 53 patients are doing well at last follow up. Conclusions  Mitral valve replacement in children is a safe alternative to valve repair when the morphology is not suitable for repair, with acceptable immediate and early outcomes.