Mechanical versus bioprosthetic valve replacement in middle-aged patients

Long-Term Risk of Hospitalization and Death in Patients With Mechanical Prosthetic Heart Valves

Mechanical prosthetic heart valves (MPHVs) are commonly used for valvular heart disease in patients with a long life expectancy. Few longitudinal data on the specific causes of hospitalization in patients with MPHV are available. We investigated the risk of all-cause hospitalization and mortality in patients with MPHV. We performed a prospective, observational, ongoing study including consecutive patients with MPHVs who were referred to the atherothrombosis outpatient clinic of the Policlinico Umberto I of Rome for the vitamin K antagonist management. Study end points were all-cause, cardiovascular hospitalization, and overall mortality. We included 305 patients with MPHV (38.4% women, median age 60.2 years). The site of MPHV was aortic in 53.5%, mitral in 29.5%, and mitroaortic in 17%. During a median follow-up of 57.3 months, 142 hospitalizations occurred (8.16 per 100 person-years). The most common causes of hospitalization were cardiovascular disease (3.62 per 100 person-years), infections, surgery, and bleeding. The predictors of cardiovascular hospitalization were atrial fibrillation (hazard ratio [HR] 1.75, 95% confidence interval [CI] 1.04 to 2.95, p = 0.035), previous stroke/transient ischemic attack (HR 2.96, 95% CI 1.59 to 5.48, p = 0.001), and peripheral artery disease (HR 2.42, 95% CI 1.09 to 5.36, p = 0.030). During a median follow-up of 97.2 months, 61 deaths occurred (2.43 per 100 person-years). Age was directly associated with the risk of death (HR 1.088, 95% CI 1.054 to 1.122, p <0.001), whereas the time in therapeutic range higher than the median was inversely associated (HR 0.436, 95% CI 0.242 to 0.786, p = 0.006). In conclusion, patients with MPHV had a high incidence of hospitalizations, especially cardiovascular-related. The incidence of death is high; however, it may be decreased by maintaining a good quality of anticoagulation.

Tissue versus mechanical mitral valve replacement in patients aged 50-70: a propensity-matched analysis

OBJECTIVES

There remains debate over the optimal mitral valve replacement (MVR) option for patients aged 50-70 years. The objective of this study was to retrospectively compare the long-term outcomes of mechanical and bioprosthetic MVR in this patient population.

METHODS

Data from patients undergoing MVR between 2004 and 2018 were retrospectively reviewed. The primary outcome was all-cause mortality. Secondary outcomes included perioperative and late morbidity.

RESULTS

Two hundred and eight-six propensity-matched patients (n = 143 mechanical; n = 143 bioprosthetic) aged 50-70 years were included in the final analysis. Maximum follow-up was 15.8 years. There was no significant difference in all-cause mortality between the groups at 30 days, 1 year, 5 years, 10 years, and at the longest follow-up. Patients who underwent mechanical MVR experienced significantly lower rates of postoperative atrial fibrillation (P = 0.001). There were no significant differences in rates of sepsis, acute kidney injury, superficial and deep sternal wound infection, mediastinal bleeding, and permanent pacemaker implantation. At the longest follow-up, there were no differences in myocardial infarction, stroke, heart failure or overall rehospitalization. At the same time point, there was an increased rate of MVR in patients receiving a bioprosthetic valve (P = 0.015).

CONCLUSIONS

Survival following mechanical and bioprosthetic MVR in patients 50-70 years of age is similar to up to 15 years of follow-up. Bioprosthetic MVR is associated with an increased risk of repeat MVR. Mechanical MVR is not associated with an increased risk of stroke. Valve selection in this patient population requires diligent consideration of structural valve deterioration and subsequent reoperation risk as well as bleeding and thromboembolic risk.

Mechanical versus Bioprosthetic Aortic Valve Replacement in Patients Aged 50 to 70 Years

Background

This study compared the outcomes of surgical aortic valve replacement (AVR) in patients aged 50 to 70 years based on the type of prosthetic valve used.

Methods

We compared patients who underwent mechanical AVR to those who underwent bioprosthetic AVR at our institution between January 2000 and March 2019. Competing risk analysis and the inverse probability of treatment weighting (IPTW) method based on propensity score were employed for comparisons.

Results

A total of 1,580 patients (984 patients with mechanical AVR; 596 patients with bioprosthetic AVR) were enrolled. There was no significant difference in early mortality between the mechanical AVR and bioprosthetic AVR groups (0.9% vs. 1.7%, p=0.177). After IPTW adjustment, the risk of all-cause mortality was significantly higher in the bioprosthetic AVR group than in the mechanical AVR group (hazard ratio [HR], 1.39; 95% confidence interval [CI], 1.07-1.80; p=0.014). Competing risk analysis revealed lower risks of stroke (sub-distributional hazard ratio [sHR], 0.44; 95% CI, 0.28-0.67; p<0.001) and anticoagulation- related bleeding (sHR, 0.35; 95% CI, 0.23-0.53; p<0.001) in the bioprosthetic AVR group. Conversely, the risk of aortic valve (AV) reintervention was higher in the bioprosthetic AVR group (sHR, 6.14; 95% CI, 3.17-11.93; p<0.001).

Conclusion

Among patients aged 50 to 70 years who underwent surgical AVR, those receiving mechanical valves showed better survival than those with bioprosthetic valves. The mechanical AVR group exhibited a higher risk of stroke and anticoagulation-related bleeding, while the bioprosthetic AVR group showed a higher risk of AV reintervention.

Early and long-term outcomes of mitral valve replacement with mechanical valve in rheumatic heart disease

Background

Rheumatic fever and rheumatic heart disease is endemic in India. Mitral valve replacement with mechanical valve is the commonest surgical procedure performed in rheumatic heart disease (RHD). However, there are no studies reporting the long-term outcomes of mechanical mitral valve replacement in rheumatic heart disease from India.

Objective

The primary objective of the study was to look at the long-term survival following mechanical mitral valve replacement in RHD. The secondary objectives included follow up complications and event-free survival.

Methods

For this study, 238 patients who underwent mitral valve replacement with TTK Chitra™ valve from 1st January 2006 to 31st December 2018 for RHD were included for analysis and reporting. The median follow-up period was 3371.50 days (9.3 years). Total follow-up was 2044 patient-years.

Results

The mean age of the study population was 39.72 ± 10.48 years (range: 18-68 years). Out of 238 patients operated, 155 patients (65.12%) were alive and 69 patients (28.99%) were dead, and 14 patients (5.88%) were lost to follow-up. The operative mortality was 6 (2.52%) and the follow-up mortality was 63 (26.47%). The reasons for follow-up mortality were cardiac complications in 22 (34.9%) patients, valve-related complications in 18 (28.5%) patients, sudden unexplained death in 13 (20.6%) patients, and non-valve/ non-cardiac death in 10patients (15.8%). The one-year survival was 94.0%, five-year survival was 83.6%, ten-year survival was 70.6% and 15-year survival was 62.9%. During follow-up, valve-related events occurred in 123(52%) patients. The 15-year event-free survival was 33.0%.

Conclusions

The long term outcome of mechanical valve replacement of the mitral valve in RHD patients was less than favorable. Both cardiac complications and mechanical valve related complications reduced their survival.

Revisiting aortic valve prosthesis choice in patients younger than 50 years: 10 years results of the AUTHEARTVISIT study

OBJECTIVES

This population-based cohort study investigated mid-term outcome after surgical aortic valve replacement with a bioprosthetic or mechanical valve prosthesis in patients aged <50 years in a European social welfare state.

METHODS

We analysed patient data from the main social insurance carriers in Austria (2010-2020). Subsequent patient-level record linkage with national health data provided patient characteristics and clinical outcome. Survival, reoperation, myocardial infarction, heart failure, embolic stroke or intracerebral haemorrhage, bleeding other than intracerebral haemorrhage and major adverse cardiac events were evaluated as outcomes.

RESULTS

A total of 991 patients were analysed. Regarding demographics, no major differences between groups were observed. Multivariable Cox regression revealed no significant difference in overall survival (P = 0.352) with a median follow-up time of 6.2 years. Reoperation-free survival was decreased (hazard ratio = 1.560 [95% CI: 1.076-2.262], P = 0.019) and the risk for reoperation was increased (hazard ratio = 2.770 [95% CI: 1.402-5.472], P = 0.003) in patients who received bioprostheses. Estimated probability of death after reoperation was 0.23 (CL: 0.08-0.35) after 2 years and 0.34 (CL: 0.06-0.53) after 10 years over both groups. Regarding further outcomes, no significant differences between the two groups were observed.

CONCLUSIONS

In patients below 50 years of age receiving aortic valve replacement, implantation of bioprostheses when compared to mechanical heart valve prostheses was associated with a significantly higher rate of reoperations and reduced reoperation-free survival. Nevertheless, we could not observe a difference in overall survival. However, long-term follow-up has to evaluate that a significantly lower rate of reoperations may translate in consistently improved long-term survival.

One-year clinical outcomes following Edwards INSPIRIS RESILIA aortic valve implantation in 487 young patients with severe aortic stenosis: a single-center experience

Introduction

The use of an aortic bioprosthesis is on the rise in younger patients with severe aortic stenosis despite the risk of accelerated structural valve degeneration (SVD). In the search for an optimal valve substitute that would not be prone to SVD, the INSPIRIS bioprosthesis represents a promising solution to lowering the risk of SVD. Here, we report the 1-year outcomes of the INSPIRIS RESILIA aortic bioprosthesis in a population of young patients who underwent aortic valve replacement.

Methods

In this prospective single-center study, we included all consecutive patients receiving INSPIRIS RESILIA bioprosthesis between June 2017 and July 2021. Patients with isolated severe aortic regurgitation were excluded. Clinical assessment and transthoracic echocardiography were performed preoperatively and at 1 year post-operatively. The primary outcome was overall mortality at one year.

Results

A total of 487 patients were included. The mean age was 58.2 ± 11.5 years, 75.2% were men. Most of the interventions were elective, with a mean EuroSCORE II of 4.8 ± 7.9. The valve annulus size in most cases was either 23 mm or 25 mm. Overall mortality at 1-year was 4.1%. At 1-year, 7 patients (1.4%) had a stroke, 4 patients (0.8%) had a myocardial infarction, and 20 patients (4.1%) were hospitalized for congestive heart failure. The Kaplan-Meier estimated survival rates and survival without major adverse cardiac events at 1-year were 96.4% and 96.7%, respectively. At 1-year follow-up, 10 patients (2.1%) had endocarditis and 1 patient (0.2%) had partial prosthetic thrombosis. Pacemaker implantation at 1-year post-operative was necessary in 27 patients (5.5%). Severe patient prosthesis mismatch and severe intra valvular regurgitation were 1.2% and 0.6%, respectively. The Kaplan-Meier estimated survival rates at 1-year of no infective endocarditis preoperative and infective endocarditis preoperative were 97.9 ± 0.7% and 89.5 ± 3.3%, respectively (P < 0.001). Excluding endocarditis-related complication, no structural valve deterioration and no valve failure requiring redo surgery were reported.

Conclusion

This is the largest single-center descriptive study of the 1-year outcomes after INSPIRIS RESILIA bioprosthesis implantation. The EDWARDS INSPIRIS RESILIA bioprosthesis provides encouraging clinical outcomes with an excellent 1- year survival rates and good hemodynamic performance. Long-term studies are mandatory to assess valve durability.

Comparison of Postdischarge Outcomes Between Valve-in-Valve Transcatheter Mitral Valve Replacement and Reoperative Surgical Mitral Valve Replacement

Limited data are available comparing the postdischarge perioperative outcomes of isolated valve-in-valve transcatheter mitral valve replacement (VIV-TMVR) versus surgical reoperative mitral valve replacement (re-SMVR) on a nationwide scale. The objective of this study was to perform a robust head-to-head assessment of contemporary postdischarge outcomes between isolated VIV-TMVR and re-SMVR using a large national multicenter longitudinal database. Adult patients aged ≥18 years with failed/degenerated bioprosthetic mitral valves who underwent either isolated VIV-TMVR or re-SMVR were identified in the 2015 to 2019 Nationwide Readmissions Database. The risk-adjusted differences in 30-, 90-, and 180-day outcomes were compared using propensity score weighting with overlap weights to mimic the results of a randomized controlled trial. The differences between a transeptal and transapical VIV-TMVR approach were also compared. A total of 687 patients with VIV-TMVR and 2,047 patients with re-SMVR were included. After the overlap weighting to attain balance between treatment groups, VIV-TMVR was associated with significantly lower major morbidity within 30 (odds ratio [95% confidence interval (CI)] 0.0.31 [0.22 to 0.46]), 90 (0.34 [0.23 to 0.50]), and 180 (0.35 [0.24 to 0.51]) days. The differences in major morbidity were primarily driven by less major bleeding (0.20 [0.14 to 0.30]), new onset complete heart block (0.48 [0.28 to 0.84]) and need for permanent pacemaker placement (0.26 [0.12 to 0.55]). The differences in renal failure and stroke were not significant. VIV-TMVR was also associated with shorter index hospital stays (median difference [95% CI] -7.0 [4.9 to 9.1] days) and an increased ability for patients to be discharged home (odds ratio [95% CI] 3.35 [2.37 to 4.72]). There were no significant differences in total hospital costs; in-hospital or 30-, 90-, and 180-day mortality; or readmission. The findings remained similar when stratifying the VIV-TMVR access using a transeptal versus a transapical approach. The changes in outcomes over time suggest marked improvements for patients with VIV-TMVR relative to stagnant results for patients with re-SMVR from 2015 to 2019. In this large nationally representative cohort of patients with failed/degenerated bioprosthetic mitral valves, VIV-TMVR appears to confer a short-term advantage over re-SMVR in terms of morbidity, discharge home, and length of stay. It yielded equivalent outcomes for mortality and readmission. Longer-term studies are needed to assess further follow-up beyond 180 days.

Infective Endocarditis-Update for the Perioperative Clinician

Infective endocarditis is a common pathology routinely encountered by perioperative physicians. There has been a need for a comprehensive review of this important topic. In this expert review, the authors discuss in detail the incidence, etiology, definition, microbiology, and trends of infective endocarditis. The authors discuss the clinical and imaging criteria for diagnosing infective endocarditis and the perioperative considerations for the same. Other imaging modalities to evaluate infective endocarditis also are discussed. Furthermore, the authors describe in detail the clinical risk scores that are used for determining clinical prognostic criteria and how they are tied to the current societal guidelines. Knowledge about native and prosthetic valve endocarditis, with emphasis on the timing of surgical intervention-focused surgical approaches and analysis of current outcomes, are critical to managing such patients, especially high-risk patients like those with heart failure, patients with intravenous drug abuse, and with internal pacemakers and defibrillators in situ. And lastly, with the advancement of percutaneous transcatheter valves becoming a norm for the management of various valvular pathologies, the authors discuss an in-depth review of transcatheter valve endocarditis with a focus on its incidence, the timing of surgical interventions, outcome data, and management of high-risk patients.

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.

Aortic valve replacement in patients aged 50 to 69 years: Analysis using Korean National Big Data

BACKGROUND

The aim of this study was to compare the clinical outcomes and long-term survival in patients who underwent isolated aortic valve replacement (AVR) with mechanical versus bioprosthetic valves.

METHODS

Patients aged 50-69 years who had undergone AVR from 2002 to 2018 were identified and their characteristics were collected from Korean National Health Information Database formed by the National Health Insurance Service, Republic of Korea. Of the 5792 patients, 1060 patients were excluded due to missing values on characteristics. Of the 4732 study patients, 1945 patients (41.1%) had received bioprosthetic valves (Group B) and 2787 patients (58.9%) had received mechanical valves (Group M). A propensity score-matched analysis was performed to match 1429 patients in each group. Data on mortality, cardiac mortality, reoperations, cerebrovascular accidents, and bleeding complications were obtained.

RESULTS

The overall survival rates at 5 and 10 years postoperatively were 87.8% and 75.2% in the matched Group B and 91.2% and 76.7% in the matched Group M, respectively (p = .140). Freedom from cardiac death rates at postoperative 5 and 10 years were 95.6% and 92.4% in the matched Group B and 96.0% and 92.1% in the matched Group M, respectively (p = .540). The cumulative incidence of reoperation was higher in the matched Group B than in the matched Group M (p = .007), and the cumulative incidence of major bleeding was higher in the matched Group M than in the matched Group B (p = .039).

CONCLUSION

In patients aged 50-69 years who underwent isolated AVR, the patients who received bioprosthetic valves showed similar cardiac mortality-free survival and long-term survival rates to the patients who received mechanical valves.

Long-Term Outcomes Stratified by Age in Patients with a Mechanical versus Biological Mitral Valve Replacement

Objectives: Balancing anticoagulation and reoperation risks determines prostheses choice (mechanical/biological) for mitral valve replacement. We aimed to re-evaluate the outcomes after biological versus mechanical mitral valve replacement. Methods: We compared long-term benefits and risks of mechanical and biological prostheses in 2056 patients (52% men, 48% women; 65.4 ± 12.1 years) who underwent mitral valve replacements between 1993−2017, in a retrospective single-centre study. Data sources included prospective institutional database, social registry, general practitioner data and follow-up questionnaire. Patients were stratified by age: < = 39 y (n = 82), 40−49 y (n = 164), 50−59 y (n = 335), 60−69 y (n = 593), 70−79 y (n = 743) and > = 80 y (n = 139). Long-term outcomes (mortality, reoperations, bleeding) were analysed. Results: Altogether, 1308 mechanical (53% men, 47% women; 61.5 ± 11.7 years) and 748 biological (50% men, 50% women; 72.3 ± 9.6 years) valves were implanted. The reason for valve replacement was stenosis in 162, insufficiency in 823 and combined in 323 cases for mechanical, while it was 46, 567 and 135 for biological valves, respectively. Overall cumulative survival was higher with mechanical prosthesis (mean: 139 ± 4 vs. 102 ± 5 months, 10 y: 55% vs. 33%, p < 0.0001). Subgroup analysis revealed higher survival among patients receiving mechanical prosthesis up to 60 years (< = 39 y p = 0.047, 40−49 y p < 0.0001, 50−59 y p = 0.001). In patients 60−69 years, overall survival did not differ; however, in survivors beyond 8 years, mechanical prosthesis showed improved survival (p = 0.014). While between 70−79 years survival was nearly identical, for above 80 years, patients had a higher survival with biological prosthesis (p = 0.014). Conclusion: The present data demonstrated a higher survival of mechanical prosthesis in a wide range of patients after mitral valve replacement.

Reimbursement Savings Associated With Tissue Versus Mechanical Surgical Aortic Valve Replacement in Thailand

OBJECTIVES

Surgical aortic valve replacement (SAVR) is an indicated treatment for severe aortic stenosis. Although mechanical valves are typically more durable, tissue SAVR valves do not require lifetime anticoagulation monitoring and may have lower rates of expensive sequelae. This economic evaluation estimates payer costs to the 3 largest Thai health insurance mechanisms for tissue versus mechanical SAVR.

METHODS

A deterministic and Monte Carlo simulation model based on literature and expert opinion estimated total payer costs for tissue and mechanical valves over a 25-year duration for 3 separate age cohorts (45, 55, and 65 years). Reimbursements levels for hospitalization services were from the Thai Diagnosis Related Groups. Separate models are generated for the 3 main Thai health insurance mechanisms.

RESULTS

The discounted expected 25-year reduction in payer savings associated with tissue SAVR are $2540, $2529, and $2311 per surgery for patients aged 45, 55, and 65 years, respectively, for the largest Thai insurer. Expected cost reductions associated with tissue SAVR are larger for each of the other schemes and generally decrease with patient age. Most savings accrue within 10 years of surgery. Reoperation costs are larger with tissue valves, but reductions in complications and anticoagulation monitoring more than offset these expenditures. Results are robust to multiple sensitivity and scenario analyses.

CONCLUSIONS

Coverage and reimbursement of tissue valves can financially benefit Thai insurers and reduce expenditures in the Thai health system compared with mechanical valves. As tissue valve technology evolves and reoperation rates decline, the financial benefit associated with tissue valves will increase.

Surgical Management of Complex Aortic Valve Disease in Young Adults: Repair, Replacement, and Future Alternatives

The ideal aortic valve substitute in young adults remains unknown. Prosthetic valves are associated with a suboptimal survival and carry a significant risk of valve-related complications in young patients, mainly reinterventions with tissue valves and, thromboembolic events and major bleeding with mechanical prostheses. The Ross procedure is the only substitute that restores a survival curve similar to that of a matched general population, and permits a normal life without functional limitations. Though the risk of reintervention is the Achilles' heel of this procedure, it is very low in patients with aortic stenosis and can be mitigated in patients with aortic regurgitation by tailored surgical techniques. Finally, the Ozaki procedure and the transcatheter aortic valve implantation are seen by many as future alternatives but lack evidence and long-term follow-up in this specific patient population.

Current surgical bioprostheses: Looking to the future

The utilization of bioprostheses for surgical heart valve replacement has been increasing across all age groups. For patients, the appeal of the bioprosthetic valve rests with the avoidance of anticoagulation, fewer thrombotic and hemorrhagic events, and the increasing availability of transcatheter valve-in-valve interventions -both in the aortic and mitral positions- allowing for lower morbidity reinterventions. While improvements in valve hemodynamics and long-term durability have made bioprostheses a reasonable choice for a growing number of patients, challenges do remain. With increasing usage of bioprostheses, especially in younger patients, there will be an increase in the projected number of failing bioprosthetic valves. This trend will bring even more emphasis to maximizing long-term durability, optimizing anticoagulation, and promoting patient-level decision making around prosthesis choice.

Mechanical or biologic prostheses for mitral valve replacement: A systematic review and meta-analysis

Either a mechanical or bioprosthetic valve is used in patients undergoing mitral valve replacement (MVR). However, the optimal mitral prosthesis remains controversial. The aim of this meta‐analysis was thus to compare outcomes between mechanical mitral valve replacement (MVRm) and bioprosthetic mitral valve replacement (MVRb) for MVR patients. We searched Embase, PubMed, Web of Science, and Cochrane Library databases from January 1, 2000 to October 31, 2021 for studies that directly compared surgical outcomes of MVRm and MVRb. A total of 22 studies with 35 903 patients were included in the meta‐analysis (n = 23 868 MVRm and n = 12 035 MVRb). The MVRm group displayed lower long‐term all causes mortality (HR, 0.84; 95% confidence interval [CI]: 0.77−0.91; p < .0001; I² = 51%), and fewer mitral reoperation (hazard ratio [HR]: 0.34; 95% CI: 0.23−0.50; p < .00001; I² = 74%) than MVRb group. However, the MVRm group was associated with a greater risk of major bleeding events (HR: 1.21; 95% CI: 1.14−1.29; p < .00001; I² = 0%), stroke and systemic embolism (HR: 1.20; 95% CI: 1.10−1.32; p < .0001; I² = 0%) in matched or adjusted data. No significant difference was observed between MVRm and MVRb on operative mortality in matched/adjusted group (risk ratios: 0.83; 95% CI: 0.66−1.05; p = .12; I² = 0%). The results were consistent with patients aged under 70 years old. Patients who received a MVRm is associated with 16% lower risk of long‐term mortality and 66% lower risk of mitral reoperation, but 20% greater risk of stroke or systemic embolism, 21% greater risk of major bleeding compared with MVRb in matched/adjusted studies group, which were consistent to patients younger than the age of 70 years who underwent MVR.

Bioprosthetic vs. Mechanical Mitral Valve Replacement for Rheumatic Heart Disease in Patients Aged 50–70 Years

Background

Rheumatic heart disease (RHD) is a critical problem in developing countries and is the cause of most of the cardiovascular adverse events in young people. In patients aged 50–70 years with RHD requiring mitral valve replacement (MVR), deciding between bioprosthetic and mechanical prosthetic valves remains controversial because few studies have defined the long-term outcomes.

Methods

1,691 Patients aged 50–70 years with RHD who received mechanical mitral valve replacement (MVRm) or bioprosthetic mitral valve replacement (MVRb) were retrospectively reviewed in Fuwai hospital from 2010 to 2014. Follow-up ended 31/12/2021; median duration was 8.0 years [interquartile range (IQR), 7.7–8.3 years]. Propensity score matching at a 1:1 ratio for 24 baseline features between MVRm and MVRb yielded 300 patient pairs. The primary late outcome was postoperative mid- to long-term all-cause mortality.

Results

Ten-year survival after MVR was 63.4% in the MVRm group and 63.7% in the MVRb group (HR, 0.91; 95% CI, 0.69–1.21; P = 0.528). The cumulative incidence of mitral valve reoperation was 0.0% in the MVRm group and 1.2% in the MVRb group (HR, 0.92; 95% CI, 0.69–1.21; P = 0.530). The cumulative incidence of stroke was 5.5% in the MVRm group and 6.1% in the MVRb group (HR, 0.89; 95% CI, 0.67–1.18; P = 0.430). The cumulative incidence of major bleeding events was 3.3% in the MVRm group and 3.4% in the MVRb group (HR, 0.92; 95% CI, 0.70–1.22; P = 0.560).

Conclusions

In patients aged 50–70 years with RHD who underwent mitral valve replacement, there was no significant difference on survival, stroke, mitral valve reoperation and major bleeding events at 10 years. These findings suggest mechanical mitral valve replacement may be a more reasonable alternative in patients aged 50–70 years with rheumatic heart disease.

Contemporary trends and in-hospital outcomes of mechanical and bioprosthetic surgical aortic valve replacement in the United States

INTRODUCTION

The choice between a mechanical versus a bioprosthetic valve in aortic valve replacement (AVR) is based on life expectancy, bleeding risk and comorbidities, since bioprosthetic AVR (bAVR) are associated with a more rapid structural deterioration compared to mechanical AVR (mAVR). The impact of widespread transcatheter valve replacements, on the decision to use bAVR versus mAVR, in the contemporary era and subsequent outcomes remain to be determined.

METHODS

The National Inpatient database (2009-2018) was used to study trends in admissions for bAVR and mAVR and in-hospital mortality and outcomes over time. Survey estimation commands were used to determine weighted national estimates.

RESULTS

There were 700,896 ± 18,285 inpatient visits for AVR with 70.1% (95% CI 69.2%-71.1%) and 29.9% (95% CI 28.9%-30.8%) visits for bAVR and mAVR, respectively. Those undergoing bAVR were significantly older (bAVR [69.8 years] vs. mAVR [62.7 years] p < .001]. The rates of mAVR decreased across all age groups during the study period (p_trend  < .001), including patients ≤50 years (p_trend  < .001). In-hospital mortality for mAVR recipients was higher, both after multivariable adjustment (OR 1.35 95% CI 1.26-1.45 p < .001) and propensity matching (mean difference 0.846% ± 0.19%).

CONCLUSION

In the contemporary era, the utilization of mAVR has decreased across all age groups, including those younger than 50 years old. Although mAVR recipients were healthier with less comorbidities, inpatient mortality was higher after mAVR compared to bAVR. In addition to understanding causes for higher in-hospital mortality after mAVR, future research should focus on developing transcatheter valve replacement friendly bAVR.

Effect of Aortic Valve Type on Patients Who Undergo Type A Aortic Dissection Repair

Aortic valve replacement (AVR) is common in the setting of type A aortic dissection (TAAD) repair. Here, we evaluated the association between prosthesis choice and patient outcomes in an international patient cohort. We reviewed data from the International Registry of Acute Aortic Dissection (IRAD) interventional cohort to examine the relationship between valve choice and short- and mid-term patient outcomes. Between January 1996 and March 2016, 1290 surgically treated patients with TAAD were entered into the IRAD interventional cohort. Of those, 364 patients undergoing TAAD repair underwent aortic valve replacement (AVR; mean age, 57 years). The mechanical valve cohort consisted of 189 patients, of which 151 (79.9%) had a root replacement. The nonmechanical valve cohort consisted of 5 patients who received homografts and 160 patients who received a biologic AVR, with a total of 118 (71.5%) patients who underwent root replacements. The mean follow-up time was 2.92 ± 1.75 years overall (2.46 ± 1.69 years for the mechanical valve cohort and 3.48 ± 1.8 years for the nonmechanical valve cohort). After propensity matching, Kaplan-Meier estimates of 4-year survival rates after surgery were 64.8% in the mechanical valve group compared with 74.7% in the nonmechanical valve group (p = 0.921). A stratified Cox model for 4-year mortality showed no difference in hazard between valve types after adjusting for the propensity score (p = 0.854). A biologic valve is a reasonable option in patients with TAAD who require AVR. Although this option avoids the potential risks of anticoagulation, long-term follow up is necessary to assess the effect of reoperations or transcatheter interventions for structural valve degeneration.

Long-term Clinical and Echocardiographic Outcomes in Young and Middle-aged Adults Undergoing the Ross Procedure

Importance

There is no ideal valve substitute for young adults requiring aortic valve replacement. Multicenter data supporting use of the Ross procedure with respect to long-term postoperative valve-related mortality and reintervention, as well as function of the autograft and pulmonary homograft, are needed.

Objective

To determine the long-term clinical and echocardiographic outcomes in young and middle-aged patients undergoing the Ross procedure.

Design, Setting, and Participants

A retrospective multicenter international cohort study with a median follow-up period of 9.2 years was conducted in 5 experienced centers regularly performing the Ross procedure. Consecutive patients aged 18 to 65 years were included by each center between 1991 and 2018.

Main Outcomes and Measures

Survival and autograft-related and homograft-related reintervention. Serial echocardiographic measurements of valve function were analyzed using mixed-effects modeling.

Results

During the study period, 1431 patients (74.3% men; n = 1063) were operated on at a median age of 48.5 years (mean [SD], 47.7 [9.5]; range, 18.1-65; interquartile range, 42.7-54.0). Implantation techniques were root inclusion in 355 (24.9%), root replacement in 485 (34.0%), and subcoronary implantation in 587 (41.1%). Right ventricular outflow tract reconstruction was performed with homografts in 98.6% (n = 1189) and bioprostheses in 1.4% (n = 17). Ten patients (0.7%) died before discharge. Median follow-up was 9.2 years (13 015 total patient-years). Survival after 10 and 15 years was 95.1% (95% CI, 93.8%-96.5%) and 88.5% (95% CI, 85.9%-91.1%), respectively. Freedom from autograft and homograft reintervention after 15 years was 92.0% and 97.2%, respectively. Late events were autograft endocarditis in 14 patients (0.11% per patient-year), homograft endocarditis in 11 patients (0.08% per patient-year), and stroke in 37 patients (0.3% per patient-year).

Conclusions and Relevance

Given its excellent short-term and long-term outcome in young and middle-aged adults in this study, the Ross procedure should be considered in young and middle-aged adults who require aortic valve replacement. Patients should be referred to an experienced center with a program dedicated to the Ross procedure.

2020 ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

This executive summary of the valvular heart disease guideline provides recommendations for clinicians to diagnose and manage valvular heart disease as well as supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from January 1, 2010, to March 1, 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, Cochrane, Agency for Healthcare Research and Quality Reports, and other selected database relevant to this guideline. Structure: Many recommendations from the earlier valvular heart disease guidelines have been updated with new evidence and provides newer options for diagnosis and treatment of valvular heart disease. This summary includes only the recommendations from the full guideline which focus on diagnostic work-up, the timing and choice of surgical and catheter interventions, and recommendations for medical therapy. The reader is referred to the full guideline for graphical flow charts, text, and tables with additional details about the rationale for and implementation of each recommendation, and the evidence tables detailing the data considered in developing these guidelines.

Atrial functional versus ventricular functional mitral regurgitation: Prognostic implications

BACKGROUND

Atrial functional mitral regurgitation (FMR) occurs because of left atrial dilatation or atrial fibrillation in heart failure with preserved left ventricular (LV) function, contrary to ventricular FMR, which occurs because of LV dysfunction. Despite pathophysiological differences, current guidelines do not discriminate between these 2 entities.

METHODS

From January 2002 to March 2019, all adult patients with ≥3+ mitral regurgitation who underwent mitral valve repair or replacement were identified. Postoperative outcomes and midterm time-to-event rates (survival and reoperation) were compared.

RESULTS

Overall, 94 atrial FMR (mean age, 67.6 years) and 84 ventricular FMR (mean age, 64 years) patients met inclusion criteria. Differences in baseline cardiac morphology and function of the atrial FMR and ventricular FMR patients were as follows: concomitant atrial fibrillation (37.2% vs 14.3%), heart failure (42.6% vs 63.1%), LV ejection fraction (60% vs 37%), at least moderate LV dilation (4.8% vs 40.6%), and moderate/severe right heart dysfunction (15.2% vs 5.1%), respectively. Operative mortality was 0% in the atrial FMR versus 1.2% in the ventricular FMR cohort. Actuarial estimates of survival and freedom from reoperation at 5 and 10 years was significantly higher in the atrial FMR cohort versus the ventricular FMR cohort. Ventricular FMR also remained a significant predictor of midterm mortality in our risk-adjusted analysis (adjusted hazard ratio for ventricular FMR, 1.8; 95% confidence interval, 1.001-3.26).

CONCLUSIONS

There are important differences in baseline characteristics in terms of cardiac morphology and function among atrial FMR and ventricular FMR patients, which appear to affect in-hospital and midterm outcomes. Because of these discrepancies, early discrimination between these 2 etiologies of FMR might facilitate more tailored approaches to management.

Bioprosthetic vs mechanical mitral valve replacement for infective endocarditis in patients aged 50 to 69 years

Background

The optimal choice of the valve prosthesis in mitral valve replacement (MVR) for infective endocarditis (IE) is controversial and challenging, particularly for younger patients.

Hypothesis

The postoperative outcomes of mechanical and biological MVR in IE patients aged 50 to 69 years are different.

Methods

All IE patients aged 50 to 69 years with primary MVR in Hubei province hospitals from 2002 to 2018 were retrospectively reviewed. The median duration of follow‐up was 8.7 years (IQR, 6.8‐10.9 years). Propensity score matching (1:3 ratio) was used to yield 492 patients with comparable baseline features between bioprostheses and mechanical prosthetic valve groups. Outcomes were postoperative mid‐ to long‐ term survival, mitral valve reoperation, prosthetic valve endocarditis (PVE), stroke, and major bleeding events.

Results

Fifteen‐year survival after MVR was 80.6% in the mechanical valve group and 69.3% in the bioprostheses group (HR 0.545, P = .040). The cumulative incidence of mitral valve reoperation was 8.8% with mechanical valves and 21.4% with bioprostheses (HR 0.260, P = .002). The cumulative incidence of PVE was 5.6% with mechanical valves and 7.2% with bioprostheses (HR 0.629, P = .435). The cumulative incidence of stroke was 12.9% with mechanical valves and 10.5% with bioprostheses (HR 1.217, P = .647). The cumulative incidence of major bleeding was 12.0% with mechanical valves and 6.75% with bioprostheses (HR 1.579, P = .268).

Conclusions

Mechanical valve prostheses were associated with better survival, lower rates of reoperation compared with bioprostheses within 15 years after MVR in IE patients aged 50 to 69. These findings suggest mechanical valve prostheses may be a more reasonable alternative to bioprostheses in this patient group.

Durability of bioprosthetic aortic valves in patients under the age of 60 years - rationale and design of the international INDURE registry

BACKGROUND

There is an ever-growing number of patients requiring aortic valve replacement (AVR). Limited data is available on the long-term outcomes and structural integrity of bioprosthetic valves in younger patients undergoing surgical AVR.

METHODS

The INSPIRIS RESILIA Durability Registry (INDURE) is a prospective, open-label, multicentre, international registry with a follow-up of 5 years to assess clinical outcomes of patients younger than 60 years who undergo surgical AVR using the INSPIRIS RESILIA aortic valve. INDURE will be conducted across 20-22 sites in Europe and Canada and intends to enrol minimum of 400 patients. Patients will be included if they are scheduled to undergo AVR with or without concomitant root replacement and/or coronary bypass surgery. The primary objectives are to 1) determine VARC-2 defined time-related valve safety at one-year (depicted as freedom from events) and 2) determine freedom from stage 3 structural valve degeneration (SVD) presenting as morphological abnormalities and severe haemodynamic valve degeneration at 5 years. Secondary objectives include the assessment of the haemodynamic performance of the valve, all stages of SVD, potential valve-in-valve procedures, clinical outcomes (in terms of New York Heart Association [NYHA] function class and freedom from valve-related rehospitalisation) and change in patient quality-of-life.

DISCUSSION

INDURE is a prospective, multicentre registry in Europe and Canada, which will provide much needed data on the long-term performance of bioprosthetic valves in general and the INSPIRIS RESILIA valve in particular. The data may help to gather a deeper understanding of the longevity of bioprosthetic valves and may expand the use of bioprosthetic valves in patients under the age of 60 years.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03666741 (registration received September, 12th, 2018).

Mitral valve prosthesis choice in patients <70 years: A systematic review and meta-analysis of 20 219 patients

BACKGROUND

The optimal mitral prosthesis in young patients is unclear. This systematic review and meta-analysis were performed to compare outcomes between bileaflet mechanical mitral valve replacement (mMVR) and bioprosthesis mitral valve replacement (bioMVR) for MVR patients aged less than 70 years.

METHODS

We searched MEDLINE and EMBASE databases from inception to July 2018 for studies comparing surgical outcomes of mMVR vs bioMVR.

RESULTS

There were 14 observational studies with 20 219 patients (n = 14 658 mMVR and n = 5561 bioMVR). Patients receiving an mMVR were younger with fewer comorbidities including renal failure, dialysis, and less-infective endocarditis (P < .001). The estimated 10-year mortality ranged from 19% to 49% for mMVR and 22% to 58% for bioMVR among studies. Comparing matched or adjusted data, mMVR was associated with lower operative (risk ratio [RR]: 0.61; 95% confidence interval [CI]: 0.39, 0.94; P = .03) and long-term (HR: 0.81; 95% CI: 0.71, 0.92; P = .002) mortality at a median follow-up of 8 years (IQR: 6-10 years). Estimated 10-year risk for mitral valve reoperation ranged from 0% to 8% for mMVR and 8% to 22% for bioMVR among matched/adjusted studies. mMVR was associated with lower matched/adjusted risk of reoperation (HR: 0.35; 95% CI: 0.19, 0.65; P = .001) but with greater risk of bleeding (HR: 1.59; 95% CI: 1.19, 2.13; P = .002) and a trend to greater risk of stroke and embolism (HR: 1.70; 95% CI: 0.92, 3.15; P = .09).

CONCLUSION

Mechanical MVR in patients aged less than 70 years is associated with a lower risk of operative mortality as well as a 20% lower risk of long-term death and 65% lower risk of mitral valve reoperation but 60% greater risk of bleeding compared with bioMVR in matched or adjusted data.

Determinants of low-quality warfarin anticoagulation in patients with mechanical prosthetic heart valves. The nationwide PLECTRUM study

Quality of warfarin therapy in patients with a mechanical prosthetic heart valve (MPHV) has been barely investigated. We analysed determinants of low time in the therapeutic range (TiTR <60%) in 2111 patients with MPHVs from the nationwide PLECTRUM study by the Italian Federation of Anticoagulation Clinics. Overall, 48·5% of patients had a TiTR of < 60%. At logistic regression analysis, arterial hypertension (odds ratio [OR] 1·502, P < 0·001), diabetes (OR 1·732, P < 0·001), heart failure (OR 1·484, P = 0·004), mitral site (vs. aortic) (OR 1·399, P = 0·006), international normalised ratio (INR) ranges of 2·5-3·5 (OR 2·575, P < 0·001) and 3·0-4·0 (OR 8·215, P < 0·001) associated with TiTR < 60%. TiTR is substantially suboptimal in MPHV patients, particularly in higher INR ranges.

Mechanical Versus Biologic Prostheses for Surgical Aortic Valve Replacement in Patients Aged 50 to 70

BACKGROUND

The use of biologic prosthesis is increasing in surgical aortic valve replacement (SAVR). Recent US guidelines recommend either biologic or mechanical prosthesis for SAVR in patients aged 50 to 70 years. We set out to study long-term outcomes of mechanical versus biologic prosthetic valves in this patient group.

METHODS

All patients (excluding infective endocarditis and concomitant surgery other than coronary artery bypass grafting) aged 50 to 70 with first-time SAVR in Finland between 2004 and 2014 were retrospectively studied (N = 2928). Propensity score matching (1:1) was used to identify patients with comparable baseline features (n = 1152). Outcomes were 10-year all-cause mortality, aortic valve reoperation, major bleeding, ischemic stroke, and infective endocarditis. Mean follow-up was 6.7 years.

RESULTS

Ten-year all-cause mortality was 18.6% with mechanical valves and 27.6% with biologic valves (hazard ratio [HR], 0.72; 95% confidence interval [CI], 0.54-0.97; P = .028). Prosthetic valve reoperation was performed in 1.4% with mechanical valves and in 8.5% with bioprosthetic valves (HR, 0.30; 95% CI, 0.12-0.74; P = .009). Major bleeding occurred in 21.5% with mechanical valves and in 16.9% with biologic prostheses (HR, 1.19; P = .402). Rates of intracranial bleeding were also comparable. Ischemic stroke rates within 10 years were 12.7% with mechanical valves and 9.3% with biologic valves (HR, 1.29; P = .316). Infective endocarditis occurred in 3.7% of mechanical valves and in 7.3% of biologic valves (HR, 0.46; 95% CI, 0.24-0.88; P = .018).

CONCLUSIONS

Mechanical valve prostheses were associated with lower mortality, lower rates of reoperation, and lower occurrence of infective endocarditis compared with bioprostheses within 10 years after SAVR in matched patients aged 50 to 70 years. Our results do not support the routine use of biologic valve prostheses in this patient group.

Systematic review and meta-analysis of surgical outcomes comparing mechanical valve replacement and bioprosthetic valve replacement in infective endocarditis

Background

Infective endocarditis (IE) is an infection involving either native or prosthetic heart valves, the endocardial surface of the heart or any implanted intracardiac devices. IE is a rare condition affecting 3-15 patients per 100,000 population. In-hospital mortality rates in patients with IE remain high at around 20% despite treatment advances. There is no consensus recommendation favoring either bioprosthetic valve or mechanical valve implantation in the setting of IE; patient age, co-morbidities and preferences should be considered selecting the replacement prosthesis.

Methods

A systematic review and meta-analysis of studies reporting the outcomes of patients undergoing bioprosthetic or mechanical valve replacement for infective endocarditis with data extracted for overall survival, valve reinfection rates and valve reoperation.

Results

Eleven relevant studies were identified, with 2,336 patients receiving a mechanical valve replacement and 2,057 patients receiving a bioprosthetic valve replacement. There was no significant difference for overall survival between patients treated with mechanical valves and those treated with bioprosthetic valves [hazard ratio (HR) 0.94, 95% confidence interval (CI): 0.73-1.21, P=0.62]. There was no significant difference in reoperation rates between patients treated with a bioprosthetic valve and those treated with a mechanical valve (HR 0.82, 95% CI: 0.34-1.98, P=0.66) and there was no significant difference in the rate of valve reinfection rates (HR 0.95, 95% CI: 0.48-1.89, P=0.89).

Conclusions

The presence of infective endocarditis alone should not influence the decision of which type of valve prosthesis that should be implanted. This decision should be based on patient age, co-morbidities and preferences.

Improved Survival After the Ross Procedure Compared With Mechanical Aortic Valve Replacement

BACKGROUND

It is unclear whether the Ross procedure offers superior survival compared with mechanical aortic valve replacement (AVR).

OBJECTIVES

This study evaluated experience and compared long-term survival between the Ross procedure and mechanical AVR.

METHODS

Between 1992 and 2016, a total of 392 Ross procedures were performed. These were compared with 1,928 isolated mechanical AVRs performed during the same time period as identified using the University of Melbourne and Australia and New Zealand Society of Cardiac and Thoracic Surgeons' Cardiac Surgery Databases. Only patients between 18 and 65 years of age were included. Propensity-score matching was performed for risk adjustment.

RESULTS

Ross procedure patients were younger, and had fewer cardiovascular risk factors. The Ross procedure was associated with longer cardiopulmonary bypass and aortic cross-clamp times. Thirty-day mortality was similar (Ross, 0.3%; mechanical, 0.8%; p = 0.5). Ross procedure patients experienced superior unadjusted long-term survival at 20 years (Ross, 95%; mechanical, 68%; p < 0.001). Multivariable analysis showed the Ross procedure to be associated with a reduced risk of late mortality (hazard ratio: 0.34; 95% confidence internal: 0.17 to 0.67; p < 0.001). Among 275 propensity-score matched pairs, Ross procedure patients had superior survival at 20 years (Ross, 94%; mechanical, 84%; p = 0.018).

CONCLUSIONS

In this Australian, propensity-score matched study, the Ross procedure was associated with better long-term survival compared with mechanical AVR. In younger patients, with a long life expectancy, the Ross procedure should be considered in centers with sufficient expertise.

[Treatment of infectious endocarditis]

Antibiotic treatment of infective endocarditis is part of a multidisciplinary patient management that should be conducted within an "Endocarditis team". Initial antibiotic treatment of infective endocarditis should be parenteral and comply with current international guidelines. A switch to an oral antibiotic regimen may be considered after 2weeks of successful parenteral antibiotic treatment. Aminoglycosides should no longer be used for the initial treatment of native valve Staphylococcus aureus endocarditis. Valve surgery is required in almost half of the patients.

Impact of valve type on outcomes after redo mitral valve replacement in patients aged 50 to 69 years

OBJECTIVES

Little data are available with regard to valve selections in redo valvular surgery. We investigated the impact of valve types on late outcomes after redo mitral valve replacement (MVR).

METHODS

We retrospectively reviewed 66 patients aged 50-69 (mean age 62.2 ± 5.1)  years who underwent redo MVR over the past 25 years. In redo MVR, 46 (69.7%) redo procedures were the 1st redo valvular surgeries, 16 (24.2%) were 2nd redos, 3 (4.5%) were 3rd redos and 1 was a 4th (1.5%) redo. We classified 66 patients into 2 groups: mechanical MVR group (M-MVR, n = 44) and biological MVR group (B-MVR, n = 22). The mean follow-up period was 8.2 ± 6.3 years.

RESULTS

Hospital mortality rates were 3.3% in M-MVR and 9.7% in B-MVR (P = 0.3328). Survival rates in M-MVR and B-MVR at 5 and 10 years were 93.0 ± 4.8% vs 76.0 ± 10.5% and 77.6 ± 9.1% vs 51.3 ± 13.7%, respectively (log-rank test, P = 0.0072). Late death occurred in 7 patients in M-MVR and 9 in B-MVR. Freedom rates from valve-related events in M-MVR and B-MVR at 5 and 10 years were 100.0 ± 0.0% vs 76.5 ± 10.3% and 93.3 ± 6.4% vs 52.4 ± 13.6%, respectively (log-rank test, P < 0.0001). No bleeding and thromboembolic events were observed in M-MVR, whereas gastrointestinal bleeding (n = 1), subarachnoid haemorrhage (n = 1) and cerebral infarction (n = 2) were observed in B-MVR. A predictor of late death was a biological valve in redo MVR (P = 0.0206, hazard ratio = 3.402, 95% confidence interval 1.207-9.591).

CONCLUSIONS

It would seem that redo MVR using a mechanical valve was associated with better early and late outcomes in this age group.

Exercise Hemodynamic and Functional Capacity After Mitral Valve Replacement in Patients With Ischemic Mitral Regurgitation

Background

In patients with ischemic mitral regurgitation requiring mitral valve replacement (MVR), the choice of the prosthesis type is crucial. The exercise hemodynamic and functional capacity performance in patients with contemporary prostheses have never been investigated. To compare exercise hemodynamic and functional capacity between biological (MVRb) and mechanical (MVRm) prostheses.

Methods and Results

We analyzed 86 consecutive patients with ischemic mitral regurgitation who underwent MVRb (n=41) or MVRm (n=45) and coronary artery bypass grafting. All patients underwent preoperative resting echocardiography and 6-minute walking test. At follow-up, exercise stress echocardiography was performed, and the 6-minute walking test was repeated. Resting and exercise indexed effective orifice areas of MVRm were larger when compared with MVRb (resting: 1.30±0.2 versus 1.19±0.3 cm 2 /m 2 ; P =0.03; exercise: 1.57±0.2 versus 1.18±0.3 cm 2 /m 2 ; P =0.0001). The MVRm had lower exercise systolic pulmonary arterial pressure at follow-up compared with MVRb (41±5 versus 59±7 mm Hg; P =0.0001). Six-minute walking test distance was improved in the MVRm (pre-operative: 242±43, post-operative: 290±50 m; P =0.001), whereas it remained similar in the MVRb (pre-operative: 250±40, post-operative: 220±44 m; P =0.13). In multivariable analysis, type of prosthesis, exercise indexed effective orifice area, and systolic pulmonary arterial pressure were joint predictors of change in 6-minute walking test (ie, difference between baseline and follow-up).

Conclusions

In patients with ischemic mitral regurgitation, bioprostheses are associated with worse hemodynamic performance and reduced functional capacity, when compared with MVRm. Randomized studies with longer follow-up including quality of life and survival data are required to confirm these results.