Using tissue mitral valves in younger patients: A word of caution.

BACKGROUND: The debate about the optimal mitral valve prosthesis continues. We aimed to compare the early and late outcomes, including stroke, bleeding, survival, and reoperation after isolated mitral valve replacement (MVR) using tissue versus mechanical valves. METHODS: This retrospective cohort study included 291 patients who had isolated MVR from 2005 to 2015. Patients were grouped into the tissue valve group (n = 140) and the mechanical valve group (n = 151). RESULTS: There were no differences in duration of mechanical ventilation, hospital stay, and hospital mortality between groups. Fifteen patients required cardiac rehospitalization, nine in the tissue valve group, and six in the mechanical valve group (p = .44). Stroke occurred in nine patients, five with tissue valves, and four with mechanical valves (p = .66). Bleeding occurred in 22 patients, seven patients with tissue valves, and 15 patients with mechanical valves (p = .09). Freedom from reoperation was 95%, 93%, 84%, 67% at 3, 5, 7, and 10 years for tissue valve and 97%, 96%, 96%, and 93% for mechanical valves, respectively (p˂ .001). The median follow-up was 84 months (Q1: Q3: 38-139). Survival at 3, 5, 7, and 10 years was 94%, 91%, 89%, 86% in tissue valves and 96%, 93%, 91%, 91% in mechanical valves, respectively (p = .49). CONCLUSIONS: Tissue valve degeneration is still an issue even in the new generations of mitral tissue valves. The significant risk of reoperation in patients with mitral tissue valves should be considered when using those valves in younger patients. Mechanical valves remain a valid option for all age groups.

Choice of valve substitutes.

Infective endocarditis often necessitates surgical intervention, and the choice of valve substitute remains a topic of controversy and highly debatable due to the wide range of available options and recent technical advancements. This manuscript reviews the different valve substitutes in the context of infective endocarditis, including mechanical and bioprosthetic valves, homografts, xenografts, and tissue-engineered valves. The patient's age, sex, demographic location, intellectual quotient, comorbidities, available options, and the experience of the surgeon should all be taken into consideration while choosing the best valve substitute for that individual. While valve repair and reconstruction are preferred whenever feasible, valve replacement may be the only option in certain cases. The choice between mechanical and bioprosthetic valves should be guided by standard criteria such as age, sex, expected lifespan, associated comorbidities, and anticipated adherence to anticoagulation therapy and accessibility of medical facilities for follow-up. For patients with severe chronic illness or a history of intracranial bleeding or associated hematological disorders, the use of mechanical prostheses may be avoided. Homografts and bioprosthetic valves provide an alternative to mechanical valves, thereby decreasing the necessity for lifelong anticoagulation after surgery and diminishing the likelihood of bleeding complications. The manuscript also discusses specific valve substitutes for different heart valves (aortic, mitral, pulmonary, tricuspid positions) and highlights emerging techniques such as the aortic valve neocuspidization (Ozaki procedure) and tissue-engineered valves. Ultimately, the ideal valve substitute in IE should be evidence based on a comprehensive elucidation of clinical condition of the patient and available options.

Rapid deployment valves versus conventional tissue valves for aortic valve replacement.

OBJECTIVES: Rapid deployment valves have been developed as a means to adjust for limitations in transcatheter aortic valve replacement and surgical aortic valve replacement for the management of aortic valve disease. To date, many studies have shown that although rapid deployment valves facilitate a shorter surgical aortic valve replacement, they offer no clinical benefit. The purpose of this study was to compare the outcomes of rapid deployment valves with conventional surgical aortic valve replacement. METHODS: This study was a retrospective review of all patients undergoing tissue aortic valve replacement at a single center. The majority of patients were men and aged more than 60 years. Patients were categorized into 2 groups: (1) rapid deployment valves and (2) conventional sutured valve. Inverse probability treatment weighting method was used to create a cohort of patients with similar baseline characteristics. Kaplan-Meier curves and log-rank tests were used to determine if there were statistically significant differences in outcomes. Primary outcome was all-cause mortality at 30 days, 1 year, and 5 years. RESULTS: A total of 2237 patients made up the study population from 2013 to 2019. After inverse probability treatment weighting, there were 295 patients in each group. Shorter cardiopulmonary bypass and crossclamp times were found with the rapid deployment valves. No statistically significant difference was found in the primary and secondary outcomes. There was a significant difference in the rate of permanent pacemaker insertion with a 7% pacemaker rate in the rapid deployment valve group (P < .009). CONCLUSIONS: The data suggest that rapid deployment valves offer no benefit in straightforward aortic valve replacement, and further study will help identify which patient population the valve is suited for.

Antithrombotic therapy and bleeding events after aortic valve replacement with a novel bioprosthesis.

OBJECTIVE: Several recent-generation surgical tissue valves have been found to have bleeding rates exceeding rates recommended by regulatory bodies. We explored bleeding events using data from the Pericardial Surgical Aortic Valve Replacement (PERIGON) Pivotal Trial for the Avalus valve (Medtronic, Minneapolis, Minn) to examine whether this end point remains relevant for the evaluation of bioprostheses. METHODS: Patients (n = 1115) underwent aortic valve replacement. Bleeding and thromboembolic event episodes in patients within 3 years postimplant were analyzed for frequency, timing, and severity, focusing on patients taking antiplatelet/anticoagulant medications at the time of the event. Clinical and hemodynamic outcomes are also reported. RESULTS: At 3 years, the Kaplan-Meier cumulative probability estimate of all-cause death was 7.2% (cardiac, 3.6%; valve-related, 1.1%). The Kaplan-Meier cumulative probability estimates of all and major hemorrhage were 8.7% and 5.2%, respectively. Ninety-nine bleeding events occurred in 86 patients: most occurred >30 days postsurgery. Among the 51 late major bleeds, in 5 cases the patients were taking anticoagulant/antiplatelet medication for prophylaxis after surgical aortic valve replacement at the time of the event, whereas the remaining patients were taking medications for other reasons. Age (hazard ratio, 1.035; 95% confidence interval, 1.004-1.068), peripheral vascular disease (hazard ratio, 2.135; 95% confidence interval, 1.106-4.122), renal dysfunction (hazard ratio, 1.920; 95% confidence interval, 1.055-3.494), and antithrombotic medication use at the time of the event (hazard ratio, 1.417; 95% confidence interval, 1.048-1.915) were associated with late bleeds (major and minor). CONCLUSIONS: Overall clinical outcomes demonstrated low mortality and few complications except for major bleeding. Most bleeding events occurred >30 days after surgery and in patients taking antiplatelet and/or anticoagulation for indications other than postimplant prophylaxis.

The current diagnosis and treatment of patients with aortic valve stenosis.

Aortic valve stenosis (AS) is the third most frequent cardiovascular abnormality after coronary artery disease and hypertension. A bicuspid aortic valve is the most common cause for AS until seventh decade and calcific valve degeneration is responsible thereafter. In symptomatic patients, The risk of death increases from ≤1%/year to 2%/month. An echo valve area ≤1 cm2, peak transaortic velocity ≥4 m/s, mean valve gradient ≥40 mmHg and/or computerized tomography valve calcium score >2000 Agatston units (AU) for males or more than 1200 AU for females indicate severe AS. AS stages and management are discussed. Valve replacement is based on surgical risk, valve durability/hemodynamics, need for anticoagulation and patient preferences. EuroSCORE ≥20%, Society of Thoracic Surgeons Predicted Risk of Mortality ≥8% and co-morbidities indicate high surgical risk. Surgery is recommended for low-intermediate risk patients. Transcatheter aortic valve implantation is an alternative in older patients at low, intermediate, high or prohibitive risk. Transaortic valve implantation/replacement trials are summarized.

Aggressive tissue aortic valve replacement in younger patients and the risk of re-replacement: Implications from microsimulation analysis.

OBJECTIVE: Advances in transcatheter aortic valve replacement have led to the consideration of tissue aortic valve replacement in younger patients. Part of this enthusiasm is the presumption that younger patients would have more flexibility in future treatment options, such as a primary surgical aortic valve replacement followed later by transcatheter aortic valve replacement(s) (valve-in-valve), vice versa, or other permutations. We created a microsimulation model using published longevity of tissue valves to predict the outcomes of patients after primary tissue surgical aortic valve replacement. METHODS: The model calculated survival by incorporating annual mortality (Social Security Administration) and mortality from re-replacements (Society of Thoracic Surgeons) in patients with surgical aortic valve replacement. Freedom from reoperation for structural valve degeneration incorporated best published data to determine the annual risk of re-replacement for structural valve degeneration based on implant duration and stratified by patient age. A constant rate of re-replacement for nonstructural valve degeneration indications was also incorporated. Each simulation was performed for 50,000 individuals. Kaplan-Meier curves were generated to represent survival. All simulations were run within the MATLAB environment (The MathWorks, Inc, Natick, Mass). RESULTS: Earlier decades of life at primary surgical aortic valve replacement were associated with higher incidences of re-replacements and especially multiple re-replacements. For those patients receiving a primary tissue surgical aortic valve replacement at age 50 years, 57.2% will require a second valve, 18.0% will require a third valve, and 1.6% will require a fourth valve with average operative mortalities of 2.9%, 4.8%, and 7.3%, respectively. A 50-year-old patient at primary surgical aortic valve replacement has a 13.1% chance of re-replacement before turning 60 years of age. CONCLUSIONS: Microsimulation incorporates changing hazards to estimate the risk of aortic valve re-replacement in patients undergoing tissue surgical aortic valve replacement and may be a starting point for patient education and health care economic planning.