Evaluation of TTK Chitra heart valve prosthesis in pediatric patients

This report highlights the outcome of valve replacement using TTK Chitra heart mechanical valve in a subgroup of pediatric patients This cohort of 27 pediatric patients with implantations during January 2006 to December 2018 was followed up prospectively. The cohort consisted of 12 aortic valve replacement (AVR), 14 mitral valve replacement (MVR), and 1 double valve replacement (DVR) patients. Total follow-up was 254 patient-years (AVR = 107, MVR = 136, DVR = 11) being 90% complete. The results show that the survival rates and event-free rates were satisfactory. Despite many reservations due to the high risk involved, the long-term benefits of having a durable valve replacement seem to outweigh the risks and offer acceptable long-term survival.     

An unusual cause of acute mitral regurgitation in TTK Chitra heart valve prosthesis

Structural failure of mechanical heart valve was a known feature when it was evolving in the 1960s and 1970s. With the advent of pyrolytic carbon and a better design, it is a rare entity with present valves. We report a case of disc fracture leading to acute mitral regurgitation in TTK Chitra heart valve prosthesis (CHVP) (TTK Healthcare Limited, India) heart valve, 6 years after its implantation in mitral position.     

Critical evaluation of clinical results with TTK-sree chitra valve

Background Rheumatic heart disease is the major indication for valve surgery in India. Majority of these patients belong to the low socio-economic groups, long term clinical results with TTK-Sree Chitra valve being presented herewith as an affordable option. Method Data was evaluated retrospectively to determine long term clinical outcome of 178 TTK-Sree Chitra valve implanted at out institution from January, 1993 through December, 2003. Mitral (n=78), Aortic (n=40) and Double valve replacement (n=30) were performed. Follow up was sought five times in this period. Total follow up was 448±2.8 patient years. Follow up was 94% complete. Results Early mortality was 2.02% (3 patients). Eight (5.4%) late deaths, of 13 total deaths, were due to valve related events (5.41%). Structural deterioration, non structural dysfunction, stuck valve and prosthetic valve endocarditis were not observed. Actuarial freedom from reoperation at 10 years was 100% for valves at both positions. Actuarial survival rate at 10 years was 89.87±7.2%. Conclusions Overall TTK-Sree Chitra valve is an excellent substitute, and cost effective.     

Long-term evaluation of TTK Chitra™ heart valve prosthesis — a retrospective-prospective cohort study

Purpose The TTK Chitra™ heart valve has more than 1,40,000 implantations so far, but no long-term data has been published. This study aims to provide long-term results of the valve.MethodologyA cohort of 476 patients with implantations from January 2006 to December 2018 were followed up prospectively consisting of 104 aortic valve replacement (AVR), 87 double valve replacement (DVR), and 285 mitral valve replacement (MVR) patients. Total follow-up was 4079 patient-years (py) (AVR = 983, MVR = 2392, DVR = 704), being 96% complete.ResultsThe results showed that actuarial survival at 15 years was 82.3% for AVR, 60.7% for MVR, and 52.2% for DVR. Freedom from all valve-related mortality and morbidity at 15 years was 73.8%, 64.8%, and 61.9% for AVR, MVR, and DVR, respectively. There was one instance of structural failure of valve disc leading to severe valvar regurgitation. Valve thrombosis incidence was 1 in AVR (0.1%/py), 6 in MVR (0.25%/py), and 1 in DVR (0.14%/py). Thrombo-embolic episodes occurred in 50 patients (AVR = 7 patients at 0.7%/py; MVR = 36 patients at 1.5%/py; DVR = 7 patients at 0.99%/py) and major hemorrhage (bleeding) in 24 patients (AVR = 0.61%/py; MVR = 0.5%/py; and DVR = 0.85%/py). The linearized rates of adverse events in this study were found to be lower than earlier published results.ConclusionThe results highlight the continued safety and performance of the TTK Chitra™ heart valve (TTKCHV) in the long term at 15 years.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12055-022-01437-9.     

Sirolimus experience in heart transplantation

INTRODUCTION: Sirolimus is a potent, nonnephrotoxic immunosuppressant with antiproliferative activity in nonimmune cells. Recent data support the conversion in late renal failure secondary to calcineurin inhibitors (CNIs), with limited experience in de novo regimens in patients with predictive factors of postoperative renal impairment. OBJECTIVE: We evaluated our experience of sirolimus-based immunosuppression administered to 25 heart transplant recipients. METHODS: A retrospective analysis of 25 heart transplant recipients who received sirolimus included 17 conversions due to late CNI-related chronic renal dysfunction, six patients with a de novo regimen, and two patients who developed posttransplant pulmonary neoplasms. The conversion from CNI to sirolimus was started with 2 mg, with an average time after transplantation of 78 +/- 43 months and a mean baseline serum creatinine level of 2.1 +/- 0.45 mg/dL. The mean clinical follow-up was 17 +/- 9 months postconversion, and included echocardiography and laboratory studies. In the de novo group successive endomyocardial biopsies were performed during the first semester. RESULTS: Serum creatinine fell from 2.1 +/- 0.45 mg/dL to 1.8 +/- 0.51 mg/dL (P = .012). Mean sirolimus levels were 15 +/- 9 ng/mL (doses 2.2 +/- 0.4 mg). This improvement continued until 3 months (creatinine 1.5 +/- 0.35 P < .01)/sirolimus levels 11.7 +/- 5 ng/mL [1.9 +/- 0.7 mg]), with maintenance at 6 months (1.58 +/- 0.3 mg/dL/14 +/- 4 ng/mL [1.85 +/- 0.7 mg]) and 1-year postconversion (1.53 +/- 0.39 mg/dL; P = .019/10.7 +/- 2.5 ng/mL [1.5 +/- 0.7 mg]). De novo, after a mean follow-up of 13 months (range 3 to 35), sirolimus appeared to increase the incidence of a moderate histological grade of rejection without hemodynamic compromise. Side effects were common (63%), including peripheral edema, skin eruptions, and pericardial effusion. Only one patient discontinued treatment, due to intestinal intolerance. Four patients died during follow-up: two because of lung neoplasms and two because of progressive graft vessel disease. CONCLUSION: Sirolimus improved late CNI-related chronic renal dysfunction. Kidney function was preserved using a de novo CNI-free immunosuppressive regimen for recent cardiac transplant recipients.     

TTK Chitra tilting disc valve: Hemodynamic evaluation

Background and aim of study The TTK Chitra mechanical heart valve is being widely used in India. We present a hemodynamic study of this valve implanted in the mitral and aortic positions. Methods 547 patients had 654 valves implanted in the aortic and/or mitral positions. 230 patients underwent an echocardiography examination with Doppler evaluation, for estimating the effective orifice area and transvalvular gradients. Results In the mitral position, for valve sizes 25, 27 and 29 mm, the mean gradients (in mm Hg) are 5±3, 4±2 and 4±2, and the Effective orifice areas (in cm²) are 2.8±0.8, 3.1±0.7 and 2.9±0.7 respectively. In the aortic position, for valve sizes 21 and 23 mm, the gradients (in mm Hg) are 10±5 and 9±4, and the Effective orifice areas (in cm²) are 1.5±0.5 and 1.8±0.3 respectively. Conclusions The TTK Chitra valve is hemodynamically comparable to other mechanical valves.     

Donor heart selection: Wythenshawe experience

BACKGROUND: The decline in the number of suitable donor hearts has led to an increasing interest in the use of previously unacceptable donors. This study aimed to evaluate the outcome of recipients of donor hearts considered medically unsuitable for transplantation at this center that were used in other centers in the United Kingdom. METHODS: Forty donor hearts (group 1) were declined by Wythenshawe Hospital and used in other units in the United Kingdom in the period extending from April 1998 to March 2003. One hundred four hearts (group 2) were transplanted at Wythenshawe Hospital during the same period. Donors and recipient data were obtained from the United Kingdom Cardiothoracic Transplant Audit database. Mortality in both groups was analyzed using SPSS software. RESULTS: Mortality in patients receiving grafts from group 1 donors was significantly higher than in group 2 (P < .0009). Of the early deaths in this group 50% (6 of 12) were the result of graft failure. These donors were receiving high doses of inotropes, had ischemic time exceeding 3.5 hours, and the grafts were transplanted into high-risk patients. CONCLUSION: Hearts declined on medical grounds by one center should be evaluated with caution before being considered suitable for transplantation, especially when more than one adverse factor is present.     

原位心脏移植的手术体会

目的 探讨原位心脏移植的手术方法及围术期处理要点。方法 2000年5月至2001年10月连续为15例病人施行了原位心脏移植术，其中扩张型心肌病14例，复杂性先天性心脏病1例，采用标准原位心脏移植手术10例，双腔静脉吻合法5例。5例术前存在中度肺动脉高压，予NO吸入等措施降肺动脉压力，抗排异治疗采用环孢素A（或FK506） 皮质激素（Pred) 骁悉（MMF）三联方案。结果 15例病人全部生存，围术期无感染，严重排异反应或右心衰等并发症发生，术后心功能恢复至Ⅰ-Ⅱ级（NYHA）。随访期间发生巨细胞病毒感染和轻度排斥反应各1例。结论 心脏移植的成功是多环节的手术操作是影响成功的重要因素。无论采用标准法或双腔静脉法，只要设计合理，均能取得良好效果。     

Severe right heart failure after heart transplantation. A single-center experience

We reviewed our heart transplantation recipient population, using hard criteria defining severe right heart failure (RHF), and analyzed possible risk factors for outcome after RHF. Between 1983 and 1998 621 cardiac transplantations were performed at our institution. RHF was defined by the necessity to implant an assist device or echocardiographically confirmed right ventricular ballooning with concomitant end organ failure. RHF patients were compared with a matched control group. Thirty-five patients (5.9%) with severe RHF after transplantation fulfilled inclusion criteria. Of these, 32 patients died, while none of the control patients died (P < 0.001). Increased preoperative pulmonary capillary wedge (P = 0.005) and mean pulmonary artery pressure (P = 0.006) were identified as significant risk factors for severe RHF. Severe RHF as defined in our study is irreversible in almost every case without differences among therapeutical concepts. Hence, improvement of postoperative outcome necessitates avoidance or aggressive therapy of possible risk factors.     

儿童心脏移植单中心临床分析

目的总结单中心儿童心脏移植关键技术和方法,为中国儿童心脏移植发展提供参考。 方法回顾性分析华中科技大学同济医学院附属协和医院心脏大血管外科2008年9月1日至2018年12月31日完成的47例儿童心脏移植临床资料,观察受者临床特征、手术相关指标、术后并发症和生存率。正态分布计量资料以均数±标准差( ±s)表示,非正态分布计量资料以中位数表示,计数资料以百分比表示。以全因死亡或再次移植为主要终点事件,运用Kaplan-Meier法计算生存率。 结果47例患儿心脏移植时年龄为(10.3±4.8)岁,男性24例,女性23例,体质量(32±15)kg,术前肺动脉压(33±12)mmHg。原发病包括：心肌病36例、复杂先天性心脏病9例和心脏肉瘤2例,4例患儿既往有心脏手术史。受者群体反应性抗体均<10%,供受者ABO血型相同39例,相容8例,供受者体质量比1.6±0.6。供心冷缺血时间为(330±115)min,其中24例冷缺血时间>6 h。采用双腔静脉法37例,双房法10例。术中体外循环时间(119±53)min,体外循环并行辅助时间(80±48) min。术后机械通气时间中位数32 h(13～1 250 h),ICU停留时间中位数7 d(5～11 d)。术后20例受者发生一种或以上并发症,包括心功能不全7例、心律失常5例、肾功能不全7例、排斥反应3例和血液系统并发症1例。受者术后3周时左心室射血分数为(67±5)%(57%～79%),46例受者顺利康复出院,1例术后59 d死于肺炎。截至2019年6月30日,46例受者平均随访时间(42±31)个月(6～129个月),术后1、3和5年生存率分别为95.74%、93.01%和93.01%。 结论心脏移植是治疗儿童终末期心脏病的有效方法。本中心儿童心脏移植术后近、中期生存率良好,建立了较为完整的儿童心脏移植技术流程,行之有效,值得借鉴。     

Ezetimibe in heart transplantation: initial experience

Dyslipidemia is a common problem among heart transplant (HT) recipients; it is a frequent risk factor in these patients that is exacerbated by immunosuppressive drugs. Statins are effective drugs to treat dyslipidemia in HT recipients, but control is suboptimal in some patients. Ezetimibe acts through inhibition of the enterohepatic recirculation, a mechanism different from but complementary to statins. Our objective was to assess the effect of the addition of ezetimibe to statin therapy among a population of HT patients. PATIENTS AND METHODS: We included 19 stable patients on statin therapy with suboptimal control of cholesterol. Determinations were performed at baseline on statins and at 6 months (statins + ezetimibe). The analyzed variables were total cholesterol and fractions, triglycerides, cyclosporine levels, CPK, SGOT/SGPT, and bilirubin. The statistics were Student's t test for paired samples. RESULTS: The overall mean age was 59 +/- 9 years with 95% males and mean BMI 27.5 +/- 3.5. The time since HT was 7 +/- 3 years. The reason for HT included ischemic heart disease in 68%. Pre-HT risk factors included in arterial hypertension in 32% and insulin-dependent diabetes mellitus in 10%, Dyslipidemia occurred in 68%; hypertriglyceridemia in 16% and hyperuricemia in 21%. Immunosuppression was cyclosporine in 100% and steroids in 94%. Type of lipid-lowering agent was simvastatin in 5%; pravastatin, 32%; atorvastatin, 58%; fibrates, 10%. The ezetimibe dose was 10 mg/day in 95% of cases. When ezetimibe was added we observed differences in total cholesterol values (total cholesterol at baseline: 279 +/- 74, total cholesterol with ezetimibe: 198 +/- 47 mg/dL; P = .0001) and LDL-cholesterol values (LDL-cholesterol at baseline: 171 +/- 69, LDL-cholesterol with ezetimibe: 109 +/- 41 mg/dL; P = .001). The remaining variables did not show significant differences. CONCLUSION: The addition of ezetimibe to statin therapy among heart transplant patients was effective to control dyslipidemia and showed an excellent safety profile.     

The first clinical experience with heart transplantation

The article analyses the first clinical experience in orthotopic allotransplantation of the heart at the Scientific Research Institute of Transplantology and Artificial Organs, USSR Ministry of Health, in the period from October, 1986 to July, 1989 (26 transplantations of the heart and one two-stage transplantation of the heart with the use of "Poisk-10M" artificial heart for 3.5 days in the first stage). Eleven patients are alive. Follow-up periods: maximum over 2.5 years, minimum 3 months. Sixteen patients died in different periods (up to 12 months). Three-component therapy (cyclosporine A, methylprednisolone, azathioprine) was applied for immunosuppression. The authors analyse the problems of the selection of potential recipients (indications and contraindications) and donor, the optimum surgical techniques, complications of immunosuppressive therapy, and infectious complications. The first clinical experience in two-stage transplantation of the heart is analysed. The first experience in transplantation of the heart in patients allows the conclusion that the use of this method for the management of the terminal stage of congestive cardiac insufficiency is a reality.     

Heterotopic heart transplantation: a single-centre experience

INTRODUCTION: Orthotopic heart transplantation (OHTx) represents the therapy of choice for end-stage heart disease not treatable with medical or conservative surgical approach. Heterotopic heart transplantation (HHTx) is a surgical procedure in which the graft is connected to the native heart in a parallel fashion and it was especially employed in precyclosporine era. The aim of this paper is to present our experience with HHTx. METHODS: From November 1985 till May 2003, 713 heart transplanted patients included 12 (1.7%) received HHTx. Eleven were male, mean age was 50.7 +/- 5.8 years. Five patients suffered from dilated cardiomyopathy and seven from ischemic cardiomyopathy. Indication for HHTx was: a body size mismatch in 11 cases and availability of a marginal organ in one case. RESULTS: Mean ischemic time was 149 +/- 48 minutes and mean cross-clamp time was 82.3 +/- 19.1 minutes. In four cases left ventricle aneurysm resection was associated with HHTx. Hospital mortality was 8.3% (one patient due to multiorgan failure). The actuarial survival rates were 92% and 64% at 1 and 5 years, respectively. The causes of death were: liver cancer, liver cirrosis, aortic dissection, cerebrovascular accident, and chronic rejection. CONCLUSIONS: In our experience, HHTx survival rate is comparable to OHTx. Because of the scarcity of donors, use of an undersized or marginal graft is a valid option to increase the number of transplanted patients. The major disadvantages of HHTx are the need for anticoagulant therapy, the more difficult hemodynamic and immunologic follow-up, and the presence of the diseased native heart.