Aortic and mitral bioprosthetic valve dysfunction: surgical or percutaneous solutions?

In the last years, there has been a trend to prefer biological prostheses, especially among young patients, with the aim to avoid anticoagulant treatment. Surgical tissue valves have so far demonstrated their solid long-term durability. However, younger age has been identified as one of the main risk factors for developing structural valve deterioration (SVD). As a consequence, the proportion of subjects at risk for valve dysfunction will constantly rise in the near future. However, while surgical reintervention has always been considered the gold standard for treatment of prosthesis deterioration, the introduction of transcatheter heart valves could offer new therapeutical options, particularly among high-risk patients, aiming a second less invasive chance. The recent standardization of valve durability definitions will soon allow a more comprehensive understanding of the mechanism underlying SVD and guide the choice of prosthesis for patients needing valve replacement.

Tricuspid Valve Replacement: Mechanical or Biological Prostheses? A Systematic Review and Meta-Analysis

Background: Tricuspid valve replacement (TVR) is seldom performed in cardiac valve surgery, and there currently are no clinical guidelines as to which type of prostheses is better in tricuspid valve position. This meta-analysis was performed to compare the results of mechanical and biological prostheses for TVR. Methods: We searched the Pubmed, Cochrane, and Embase clinical trial databases to collect all related studies published from January 1, 2000 to July 31, 2020. A random-effects model was used to evaluate the odds ratios (OR) and its 95% confidence intervals (CI) of time-to-event related effects of the surgical procedures; every study’s quality was evaluated by the Newcastle-Ottawa Scale (NOS). Results: A total of 13 retrospective studies, including 1453 patients were analyzed. There were no statistically differences between mechanical and biological prostheses with respect to prosthetic valve failure [OR = 0.84, 95% CI(0.54, 1.28), P = .41], bleeding [OR = 0.84, 95% CI(0.54,1.28), P = .41], reoperation [OR = 1.02, 95% CI(0.58,1.78), P = .95], early mortality [OR = 1.35, 95% CI(0.82,2.25), P = .24] and long-time survival [OR = 1.09, 95% CI(0.70, 1.69), P = .70], but a significant difference can be seen in mechanical prostheses with a higher risk of thrombosis [OR = 0.17, 95% CI(0.05, 0.60), P = .006, I2 = 0%]. Conclusions: In tricuspid valve position, mechanical valve prostheses have a higher risk of thrombosis than biological prostheses, but no statistical differences between mechanical and biological prostheses with respect to prosthetic valve failure, bleeding, reoperation, early mortality, and long-term survival. The valve disease and patient’s age and risk factors are the most important considerations in the decision-making process. The more specific conclusion needs to be further proved by large-sample, multi-center, randomized, double-blind and control trials.

Aortic valve leaflet replacement using autopericardium as an alternative approach of aortic valve stenosis treatment: literature review

Regarding degenerative defects of the aortic valve, the main method of treatment is dissection of malformed leaflets and placement of prosthetic valve. In most cases, mechanical and biological prostheses are used. Each type of prosthesis has shortcomings related to both the implantation technique and essential medication support to keep it functioning. Patients with implanted mechanical prosthesis need lifelong anticoagulation therapy and constant monitoring of blood coagulation rates, where on the one hand there is a risk of occurring thromboembolic complications, and on the other hand haemorrhagic complications. The peculiarity of biological prostheses is a high probability of degeneration and the need for re-operation, especially in young patients, therefore the implantation of such prostheses is mainly carried out in elderly patients. Despite continuous change and modification of artificial valves, the ideal aortic valve prosthesis does not exist today. Various attempts to replace aortic valve leaflets with artificial and biological materials have not succeeded or gained great recognition. In 2007, Shigeyuki Ozaki introduced a technique to replace the aortic valve leaflets with an autopericardium treated with 0.6 % glutar aldehyde solution. Inspite of the encouraging mid-term results, this surgery has not yet become widespread among cardiac surgeons due to the complicated operating technique and lack of long-term results. Considering the research of literature, experience of different cardiosurgical centers in this field as well as our own experience, there is a need to systematize the results of Ozaki procedure, among patients with aortic valve pathology, presented in the recent publications.

Aortic valve replacement with biological prosthesis in patients aged 50–69 years

OBJECTIVES There is no consensus regarding the use of biological or mechanical prostheses in patients 50–69 years of age. Previous studies have reported a survival advantage with mechanical valves. Our goal was to compare the long-term survival of patients in the intermediate age groups of 50–59 and 60–69 years receiving mechanical or biological aortic valve prostheses. METHODS We conducted a retrospective analysis of patients in the age groups 50–59 years (n = 329) and 60–69 years (n = 648) who had a first-time isolated aortic valve replacement between 2000 and 2019. Kaplan–Meier and competing risk analyses were performed to compare survival, incidence of aortic valve reoperation, haemorrhagic complications and thromboembolic events for mechanical versus biological prostheses. RESULTS Patients aged 50–59 years with a biological prosthesis had a higher probability of aortic valve reintervention (26.3%, biological vs 2.6% mechanical; P < 0.001 at 15 years). The incidence of haemorrhagic complications or thromboembolic events was similar in the 2 groups. Patients aged 60–69 years with a mechanical prosthesis had a higher risk of haemorrhagic complications (6.9%, biological vs 16.2%, mechanical; P = 0.001 at 15 years). Biological prostheses had a higher overall probability of reintervention for valve dysfunction (20.9%, biological vs 4.8%, mechanical; P = 0.024). In both age groups, there was no difference in long-term survival between patients receiving a biological or a mechanical prosthesis. CONCLUSIONS There was no difference in long-term survival between mechanical and biological prostheses for both age groups. Mechanical prostheses had a higher risk of bleeding in the 60–69-year group whereas biological valves had higher overall reintervention probability without an impact on long-term survival. It may be safe to use biological valves based on lifestyle choices for patients in the 50–69-year age group.

Which is the best prosthesis in an isolated or combined tricuspid valve replacement?

OBJECTIVES The debate concerning the optimal choice of tricuspid position continues. We compared the long-term results of mechanical and biological prostheses in patients who underwent isolated or combined tricuspid valve replacement, at 2 major cardiac surgical centres in central China. METHODS From January 1999 to December 2018, 338 patients underwent tricuspid valve replacement. Patients were divided into an isolated group or a combined group according to whether their surgery was combined with a left heart valve surgery. Mechanical tricuspid valve replacement was performed in 142 patients (isolated group: 41 vs combined group: 101), and 196 patients underwent bioprosthetic tricuspid valve replacement (isolated group: 145 vs combined group: 51). Operative results, long-term survival and tricuspid valve-related events were compared. RESULTS Early mortality in the combined group was higher (n = 6, 4%) than that in the isolated group (n = 3, 2%), but no significant difference was observed between the mechanical and biological subgroups. In the isolated group, there was a higher event-free rate in the biological subgroup than in the mechanical subgroup (P = 0.042) and a similar result was also observed for patients without Ebstein’s anomaly (P = 0.039). In the combined group, no significant difference was observed (P = 0.98). Survival rates were similar between the mechanical and biological subgroups in both the isolated (P = 0.54) and combined (P = 0.81) groups. Mechanical valves in isolated tricuspid valve replacement were more prone to valve thrombosis and bleeding. CONCLUSIONS Every decision regarding tricuspid valve prostheses should be individualized, but biological prostheses may be an optimal choice for patients, especially for patients without Ebstein’s anomaly, in isolated tricuspid valve replacement.

“Valve-On-Valve” — an alternative method of surgical treatment of tissue valve dysfunctions

Every year, the frequency of use of biological prostheses for treatment of valvular heart disease increases.The implantation of a biological prosthesis allows avoiding lifelong anticoagulant therapy, but at the same time it may require further replacement due to the dysfunction development.Traditional reoperation is associated with a certain risk of trauma to various structures and cardiac chambers during explantation of non-functioning valve.Transcatheter replacement of the prosthesis (“valve-in-valve”) is not always realizable due to lack of routes for the delivery system and small diameter of the initial valve.“Valve-in-valve” is not always demanded because it does not provide an option to choose mechanical or biological prosthesis.Valve-on-valve implantation technique implies that the new prosthesis is implanted in the carcass of the previous valve. It allows avoiding severe intraoperative complications, reducing the duration of the main stage of the surgery and adverse events in the early postoperative period, and provide an option to choose implantable device.In this review, the authors attempted to comprehensively evaluate the world experience in applying the “valve-on-valve” technique.