Bioprosthetic valves — An initial experience

Aim. The aim of the study was to assess the functional status, performance and complications of bioprosthetic valves implanted in forty five consecutive patients at All India Institute of Medical Sciences, New Delhi between January 2000 and September 2001. Method. The preoperative, operative and postoperative data were collected from case records and at follow up. Results. Hospital Mortality was 6.6% (3 out of 45) and incidence of all complications was 4.9%. There was one valve related death (2.4%). There was no structural failure or anticoagulant related haemorrhage. The incidence of thromboembolism and infective endocarditis were 2.4%. Postoperative gradients were low. Conclusion. The early clinical performance and in vivo hemodynamics of Carpentier Edwards (Porcine) bioprosthesis in our experience is satisfactory.     

In-hospital outcomes of patients undergoing concomitant aortic and mitral valve replacement in Germany

 Open in a separate windowOBJECTIVESTo evaluate in-hospital outcomes of concomitant mitral valve replacement (MVR) in patients undergoing conventional aortic valve replacement due to aortic stenosis in a nationwide cohort.METHODSAdministrative data from all patients with aortic stenosis undergoing conventional aortic and concomitant MVR (reason for MVR not specified) between 2017 and 2018 in Germany were analysed.RESULTSA total of 2597 patients with a preoperative logistic EuroScore of 9.81 (standard deviation: 8.56) were identified. In-hospital mortality was 6.8%. An in-hospital stroke occurred in 3.4%, acute kidney injury in 16.3%, prolonged mechanical ventilation of more than 48 h in 16.3%, postoperative delirium in 15.8% and postoperative pacemaker implantation in 7.6% of the patients. Mean hospital stay was 16.5 (standard deviation: 12.1) days. Age [odds ratio (OR): 1.03; P = 0.019], New York Heart Association class III or IV (OR: 1.63; P = 0.012), previous cardiac surgery (OR: 2.85, P = 0.002), peripheral vascular disease (OR: 2.01, P = 0.031), pulmonary hypertension (OR: 1.63, P = 0.042) and impaired renal function (glomerular filtration rate <15, OR: 3.58, P = 0.001; glomerular filtration rate <30, OR: 2.51, P = 0.037) were identified as independent predictors for in-hospital mortality.CONCLUSIONSIn this nationwide analysis, concomitant aortic and MVR was associated with acceptable in-hospital mortality, morbidity and length of in-hospital stay. The regression analyses may help to identify high-risk patients and further optimize treatment strategies.     

Is this a bridge too far?

Maeda et al. present what may be the second reported case of transcatheter aortic valve replacement (TAVR) followed by staged open surgical aortic valve replacement (SAVR) in a high‐risk patient. The authors propose that TAVR may serve as a bridge procedure before SAVR for aortic stenosis in selected younger patients with high surgical risk. Further experience may clarify how long to wait after TAVR to perform SAVR. Timing will be a balance between improving surgical risk versus increasing difficulty removing the prosthesis. Knowledge of TAVR durability will ultimately be needed to decide between “destination” TAVR versus bridging to SAVR with a more durable device.     

Transcatheter aortic valve replacement as a bridge to surgical aortic valve replacement in a younger patient with extremely high surgical risk

A 50‐year‐old man with decompensated aortic stenosis displayed significantly reduced ejection fraction, an ascending aortic aneurysm (55 mm in diameter), and bilateral giant bullae, and was evaluated as having extremely high surgical risk. Therefore, as a bridge to definitive treatment, he simultaneously underwent transcatheter aortic valve replacement (TAVR) and upper left lung lobectomy. His heart function recovered 6 months later and he underwent surgical aortic valve replacement (SAVR) and graft replacement of the ascending aorta. TAVR may serve as a bridge procedure before SAVR for aortic stenosis in younger patients with high surgical risk.     

Selection of Prosthetic Valve and Evidence—Need for the Development of Japan’s Own Guidelines

Purpose: In 2014, the American Heart Association (AHA)/American College of Cardiology (ACC) guidelines were largely revised with regard to the selection of prosthetic valves. (1) A mechanical prosthesis is reasonable for aortic valve replacement (AVR) or mitral valve replacement (MVR) in patients less than 60 years of age, (2) A bioprosthesis is reasonable in patients more than 70 years of age, and (3) Either a bioprosthetic or mechanical valve is reasonable in patients between 60 and 70 years of age.Japan faces the unprecedented population aging, and moreover, the average life expectancy is longer among the Japanese than the Westerners. In Japan, whether this choice is appropriate seems questionable.Methods: This time, with the revision of the AHA/ACC guidelines, it might be necessary to take into consideration the average life expectancy of Japanese people and revise the Japanese guidelines accordingly.Results: We should consider whether 60–70 years should be set as a gray zone regarding the age criteria for choosing biological valves, or if the age should be set higher relative to that specified in the western guidelines, given the longer Japanese life expectancy.Conclusion: We believe that the development of unique, Japanese guidelines for the selection of prosthetic valves will allow us to provide appropriate selection and treatment for each patient.     

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.     

主动脉瓣置换术前合并中度功能性二尖瓣关闭不全治疗策略的回顾性队列研究

目的分析主动脉瓣置换术(aortic valve replacement,AVR)同期不同方式处理中度功能性二尖瓣关闭不全(functional mitral regurgitation,FMR)对患者预后的影响。方法回顾性纳入2014～2018年在本中心接受AVR且合并中度FMR的118例患者,其中男84例、女34例,年龄(58.1±12.4)岁。根据不同二尖瓣处理方式将患者分为三组:A组(未处理,11例)、B组(二尖瓣修复,51例)及C组(二尖瓣置换,56例)。研究主要终点为患者近中期生存情况,次要终点为FMR改善情况。结果中位随访时间为29.5个月。围术期死亡5例,均为C组患者;术后早期A、B两组FMR改善率分别为90.9%、94.1%(P=0.694)。A、B、C三组中期死亡率分别为0.0%、5.9%、3.9%(P=0.264),而主要心脑血管病事件发生率分别为0.0%、9.8%、17.7%(P=0.230)。A、B两组中期FMR改善率分别为100.0%、94.3%(P>0.05)。结论对于接受AVR合并中度FMR的患者,不处理或同期修复二尖瓣更为合理,而二尖瓣置换可能会...     

Rapid-deployment aortic valve replacement after aortic root replacement: A safe alternative to redo root replacement

Reoperative aortic root replacement, following prior biologic or mechanical valved conduit aortic root prosthesis, presents a technical challenge. The rapid-deployment aortic valve prosthesis is an approved alternative to traditional bioprosthetic aortic valve replacement. We present three clinical cases in which rapid-deployment aortic valve prostheses were utilized in lieu of reoperative full aortic root replacement. All three patients recovered uneventfully. The rapid-deployment valve insertion in a prior surgical aortic root prosthesis is a safe option to avoid reoperative full aortic root replacement.     

Comparison of Two Automatic Staplers for Closing the Bronchial Stump after Pulmonary Resection

The incidence of complications following pulmonary resection using an automatic stapler was studied in 348 consecutive patients. A parallel-jaw stapler with two staple lines was used in group A (133 males, 101 females, mean age 66 years) between 1990 and 1995, and a hinged-jaw stapler with three staple lines in group B (70 males, 44 females, mean age 67 years) in 1995-1997. The incidence of bronchopleural fistula was 0.4% (1 patient) in group A and nil in group B. The incidence of intraoperative air leak requiring interrupted suture closure was 4.7% (11 patients) in group A and nil in group B (p &lt; 0.05). Postoperative bronchopleural fistula did not develop in any of the cases, and there was no mortality. For management of the bronchial stump after pulmonary resection, the newer device firing three rows of staples is superior to the two-row device.     

Liver Regeneration in Rats Treated with the Antiandrogen Flutamide

Previous studies have shown that male rat liver undergoes demasculinization during hepatic regeneration after partial hepatectomy. In the present study the effect of the antiandrogen flutamide on liver regeneration was assessed. Adult male Wistar rats were treated with flutamide (2 mglratl day or 5 mglratlday subcutaneously) or vehicle for 3 days prior to and daily after partial hepatectomy. Rates of DNA and poly amine synthesis were assessed by measuring thymidine kinase and ornithine decarboxylase activities, respectively. The rate of liver growth after partial hepatectomy in the three groups was similar at all time points examined. The increases in thymidine kinase activity and ornithine decarboxylase activity after partial hepatectomy were comparable throughout the study. Thus, administration of flutamide did not influence the regenerative response after partial hepatectomy     

Atrial and ventricular flows across a transcatheter mitral valve

 Open in a separate windowOBJECTIVESThe objective of this study was to evaluate the haemodynamic performance of transcatheter mitral valve replacement (TMVR) Implant with a focus on turbulence and washout adjacent to the ventricular surface of the leaflets. TMVR holds the promise of treating a large spectrum of mitral valve diseases. However, the haemodynamic performance and flow dynamics of such replacements are not fully understood. METHODSA tri-leaflet biopsrosthetic TMVR represented by Caisson implant of size 36A was implanted in the mitral position of a left heart simulator pulse duplicating system under physiological conditions. The 36A implant covers an anterior–posterior range of 26–32 mm and a commissure-to-commissure range of 30–36 mm. Transmitral pressure gradient, effective orifice area and regurgitant fraction were calculated. Particle image velocimetry was performed to evaluate turbulence in 2 perpendicular planes (Reynolds and viscous shear stresses, respectively). Additionally, dye experiments were performed to visualize washout.RESULTSTransmitral pressure gradient was 1.29 ± 0.27 mmHg and effective orifice area was 2.96 ± 0.28 cm². Regurgitant fraction was 14.13 ± 0.08%. Total washout was 4.27 cardiac cycles. Largest viscous shear stress reaches 3.7 Pa and 2.4 Pa in ventricle and atrium, respectively. Reynolds shear stress in the atrial side was <10 Pa. In the ventricular side, the largest Reynolds shear stress reached ∼35 Pa.CONCLUSIONSTMVR leads to favourable haemodynamics with low degree of turbulence combined with fast washout around the leaflets indicating promising potential for freedom from blood damage potential and thrombosis corroborated by initial clinical studies as part of the valves’s Early Feasibility Study.     

Experimental evaluation and early clinical results of a new low-profile bileaflet aortic valve

We performed an experimental and clinical evaluation of a new low-profile bileaflet aortic valve (Regent, St. Jude Medical Inc., St. Paul, MN, U.S.A.). Common valve sizes were experimentally tested for leakage volume, pressure drop, and transvalvular hemodynamics using a pulse duplicator. Thirty patients (mean age 60 +/- 7 years, predominant valve stenosis n = 25) received the Regent prosthesis for initial clinical evaluation. In vitro evaluation revealed equivalent leakage volumes, larger performance indices (0.552 versus 0.513), and lower pressure drops in comparison to SJM hemodynamic plus valve controls. Clinically, 21 mm (n = 9), 23 mm (n = 12), and 25 mm (n = 9) valves were implanted with no significant perioperative complications. Echocardiography revealed low transvalvular flow velocities (2.2 +/- 0.4 m/s) and low pressure gradients (20 +/- 6 mm Hg) postoperatively and at 6 months follow-up. In vitro testing and early clinical results are promising; however, long-term performance has to be proven.     

New approach for replacement of degenerated mitral bioprostheses

OBJECTIVE: The most common indication for reoperation in patients with a mitral bioprosthetic valve is primary tissue failure. Explanation of the bioprosthesis is time-consuming and may be complicated by cardiac rupture at the atrioventricular junction or the posterior left ventricular wall where a strut is imbedded, injury to the circumflex artery and late perivalvular leak. A new approach to avoid these complications by excising only the bioprosthetic tissue and attaching a reversed aortic St. Jude valve to the intact stent has been developed and evaluated. METHODS: We have replaced degenerated mitral bioprostheses with a St. Jude valve in 73 patients during the last 12 years. In 57, including all who had their operation before 1991, explantation was used. The stent was preserved in 16 patients; in the first four we implanted a mitral St. Jude valve (SJM) within the stent, but this only allows a SJM 6-8 mm smaller than the bioprosthesis. We evolved our approach in the last 12 patients to suture a reversed aortic St. Jude valve with extended cuff to the atrial side of the bioprosthetic cuff; this allows the use of a St. Jude valve 2 mm smaller than the bioprosthesis with exact matching of the orifice sizes. The demographic and clinical profiles of the two groups were similar. RESULTS: Operative mortality was 8/57 (14%) in the explantation group and none in the stent-preservation group. Three late perivalvular leaks occurred in the explanation group, and none in the stent-preservation group. Thirteen late deaths occurred in the explanation group, with a 5-year survival rate of 68%, and one late death (cancer) in the stent-preservation group, but the follow-up is significantly shorter. CONCLUSIONS: Leaving the mitral bioprosthetic stent and cuff intact eliminates the need for extensive dissection, thus shortening and simplifying the procedure and diminishing its attendant mortality and morbidity. It offers a safe and logical approach to replacement of a degenerated mitral bioprosthesis with a St. Jude valve of comparable size which projects into the left atrium, rather than a smaller one jammed into the orifice of the bioprosthetic stent.     

Robotic mitral valve repair in a type B hemophiliac

Hemophilia B is a rare X-linked recessive disorder that places surgical patients at an increased risk of bleeding. Patients with hemophilia are now achieving near-normal life expectancies and therefore the number of these patients requiring cardiac surgery due to the development of age-related cardiovascular disease may increase. We present the case of a young male with hemophilia B who was diagnosed with severe symptomatic mitral regurgitation and underwent successful robotic mitral valve repair. To our knowledge, this is the first report of a patient with hemophilia B who underwent robotic mitral valve repair.