Valve Selection in End-Stage Renal Disease: Should It Always Be Biological?

Cardiac evaluation in patients awaiting kidney transplant-position statement of the Cardiological Society of India and Indian Society of Nephrology

Cardiovascular diseases are a major cause of death after kidney transplantation. This statement addresses preoperative cardiac decision-making and management with the aim of assessing and reducing the risk of the kidney transplant surgery. Important issues from a clinician's perspective include the basic cardiovascular workup of these patients, coronary evaluation and management of coronary artery disease, valvular heart disease and left ventricular systolic dysfunction. Recovery left ventricular function after kidney transplant is discussed. In addition, the use of cardiovascular drugs in patients with special emphasis on antiplatelets and anticoagulants in patients planned for kidney transplant is also discussed.

Mechanical versus bioprosthetic valve for aortic valve replacement in dialysis patients: Systematic review and individual patient data meta-analysis

OBJECTIVE

There is little evidence regarding the most beneficial choice between a mechanical and a bioprosthetic valve in the aortic position in dialysis patients. This meta-analysis compares the survival and freedom from reintervention rates between mechanical and bioprosthetic valves in patients on dialysis undergoing aortic valve replacement surgery.

METHODS

Two databases were searched, and the systematic review was performed in accordance with the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement. We conducted one-stage and two-stage meta-analysis with Kaplan-Meier-derived individual patient data and meta-analysis with random-effects model.

RESULTS

Eight studies were included, providing data about 1215 dialysis patients receiving mechanical valves and 1851 patients receiving bioprosthetic valves. During a mean follow-up of 43.1 months, overall survival rates were significantly improved in the mechanical valve group in comparison to the bioprosthetic one (hazard ratio [HR]: 0.76, 95% confidence interval [CI]: 0.69-0.84, p < 0.001). This was confirmed by the two-stage meta-analysis (HR: 0.72, 95% CI: 0.62-0.83, p = 0.00, I2 = 17.79%). Regarding freedom from reintervention, no arm offered a statistically significant advantage, according to the two-stage generated analysis (HR: 1.025, 95% CI: 0.65-1.61, p = 0.914). Similarly, there was no evident superiority of a valve type for perioperative outcomes.

CONCLUSIONS

Mechanical valves are likely to be associated with a better survival outcome compared to bioprosthetic valves for patients on dialysis undergoing aortic valve replacement. However, freedom from reoperation rates and perioperative outcomes were comparable between the two valve types, with no arm exhibiting a statistically significant advantage.

Long-term outcomes of mitral valve replacement in dialysis patients: evidence from a nationwide database

BACKGROUND

To compare the late outcomes between mechanical and bioprostheses after isolated mitral valve replacement (MVR) in dialysis-dependent patients.

METHODS

A nationwide propensity-matched retrospective cohort study was conducted involving dialysis patients who underwent primary mitral replacement between 2001 and 2018. Ten-year postoperative outcomes were compared between mitral bioprosthesis and mechanical prosthesis using the Cox proportional hazard model and restricted mean survival time (RMST).

RESULTS

The all-cause mortality was 20.8 and 13.0 events per 100 person-years, with a 10-year RMST of 7.40 and 7.31 years for bioprosthesis and mechanical prosthesis, respectively. Major bleeding was the most common adverse event for both bioprosthesis and mechanical prosthesis, with an incidence rate of 19.5 and 19.1 events per 100 person-years, respectively. The incidence of valve reoperation was higher among those who received bioprosthesis (0.55 events per 100 person-years). After 1:1 matching, the all-cause mortality was 15.45 and 14.54 events per 100 person-years for bioprosthesis and mechanical prosthesis, respectively. The RMST at 10 years was comparable between the two groups after matching (5.10 years for bioprosthesis vs. 4.59 years for mechanical prosthesis), with an RMST difference of -0.03. Further, no difference was observed in the incidence of major adverse valve-related events between bioprosthesis and mechanical valves. However, bioprosthesis was associated with a higher incidence of mitral valve reoperation among all major adverse events (RMST difference -0.24 years, 95% CI -0.48 to -0.01, P =0.047).

CONCLUSIONS

This study found no association between valve selection and long-term survival outcomes in dialysis patients after MVR. However, bioprosthetic valves may be associated with a slightly higher incidence of reoperation, while other valve-related adverse events, including major bleeding and stroke, were comparable between the two types of prostheses.

Mechanical vs Bioprosthetic Aortic Valve Replacement in Patients on Dialysis: Long-term Outcomes

BACKGROUND

Using the Japan National Clinical Database and additional data, this study is an analysis of long-term survival of dialysis-dependent patients who underwent aortic valve replacement (AVR).

METHODS

Dialysis-dependent patients who underwent de novo AVR between 2010 and 2012 and who were registered in the database were included. Concomitant aortic surgery and transcatheter aortic valve replacement were excluded. Additional data on the underlying kidney disease, the duration of dialysis, and clinical outcomes were registered between October 29, 2019, and August 30, 2020. The primary outcome was all-cause mortality. The secondary outcomes were cerebral infarction, cerebral bleeding, gastrointestinal bleeding, and prosthetic valve failure.

RESULTS

After propensity score matching, 1016 cases (508 each in the bioprosthetic and mechanical valve groups) were matched. The median follow-up period was 3.29 years (interquartile range [IQR], 0.59 years, 6.25 years). The median survival time was 5.38 years (IQR, 1.20 and 9.26 years) in the mechanical valve group and 4.98 years (IQR, 1.69 and 9.62 years) in the bioprosthetic valve group. The Cox regression model showed no significant difference in long-term survival between the groups (mechanical valve: hazard ratio [HR], 0.895; 95% CI, 0.719-1.113; P = .318). The incidences of cerebral infarction and prosthetic valve failure requiring admission were similar between the groups. Cerebral bleeding (HR, 2.143; 95% CI, 1.125-4.080; P = .002) and gastrointestinal bleeding (HR, 2.071; 95% CI, 1.243-3.451; P = .0005) were more frequent in the mechanical valve group.

CONCLUSIONS

Long-term survival of dialysis-dependent patients was similar regardless of whether mechanical valves or bioprosthetic valves were implanted. The incidences of cerebral and gastrointestinal bleeding were 2-fold higher in the mechanical valve group.

The influence of renal disease on outcomes and cardiac remodeling following surgical mitral valve replacement

OBJECTIVES

Chronic kidney disease (CKD) is increasingly prevalent in patients undergoing mitral valve replacement (MVR). While CKD is known to result in suboptimal outcomes for patients with mitral valve disease, there is limited literature evaluating the long-term outcomes and cardiac remodeling of patients with CKD undergoing MVR. We present the first analysis coupling long-term outcomes of combined morbidity, mortality, and cardiac remodeling post-MVR in patients with CKD.

METHODS

Patients with varying degrees of CKD undergoing MVR from 2004 to 2018 were compared. Patients were grouped by estimated glomerular filtration rate (eGFR) > 90 mL/min/1.73m² (n = 109), 60-89 mL/min/1.73m² (450), 30-59 mL/min/1.73m² (449), < 30 mL/min/1.73m² (60). The primary outcome was mortality. Secondary outcomes included measures of postoperative morbidity and cardiac remodeling.

RESULTS

One-year mortality was significantly increased in patients with eGFR < 30 (p = 0.023). Mortality at 7 years was significantly increased in patients with eGFR < 30 mL/min/1.73m² (p < 0.001). Multivariable regression analysis of 7-year all-cause mortality indicated an eGFR of 15 mL/min/1.73m² (HR 4.03, 95% CI 2.54-6.40) and 30 mL/min/1.73m² (HR 2.17 95% CI 1.55-3.05) were predictive of increased mortality. Reduced eGFR predicted the development of postoperative sepsis (p = 0.002), but not other morbidities. Positive cardiac remodeling of the left ventricle, left atrium, and valve gradients were identified postoperatively for patients with eGFR > 30 mL/min/1.73m² while patients with eGFR < 30 mL/min/1.73m² did not experience the same changes.

CONCLUSIONS

CKD is predictive of inferior clinical and echocardiographic outcomes in patients undergoing MVR and consequently requires careful preoperative consideration and planning. Further investigation into optimizing the postoperative outcomes of this patient population is necessary.

Recurrent ST-elevation myocardial infarction: a case report of a rare complication of caseous mitral annular calcification

Background

Caseous mitral annular calcification (MAC) is an under-diagnosed division of calcific mitral valve disease that has recently been reported to have increased propensity for embolic disease. Early recognition of this entity as a cause of embolic disease can lead to prevention of occlusive vascular disease and long-standing complications.

Case summary

We present the case of a patient with end-stage renal disease who presented for evaluation of chest pain and was found to have ST-segment myocardial infarction. Despite thrombectomy and stenting, he had multiple recurrent events, and imaging evaluation demonstrated caseous MAC with mobile components. He was taken for surgical replacement of the mitral valve, with pathology confirming diagnosis.

Discussion

Caseous MAC may represent an increased risk of embolic disease. Better understanding of this pathology and it’s propensity for embolic disease will be important to best determine treatment plans and timing of operative intervention.

Long-Term Outcomes of Bioprosthetic or Mechanical Valve Replacement in End-Stage Renal Disease: A Nationwide Population-Based Retrospective Study

Background: Valve replacement is associated with worse outcomes in individuals who have end-stage renal disease (ESRD) and require a long-term renal replacement therapy. Prosthetic valve selection in patients with ESRD has remained controversial.

Objective: We aimed to investigate long-term outcomes of mechanical and bioprosthetic valve replacement in individuals with ESRD.

Methods: We conducted a population-based retrospective cohort study using data obtained from the Taiwan National Health Insurance Research Database. In total, 10,202 patients, including 912 ESRD and 9,290 non-ESRD patients, were selected after a 1:1 propensity-score matching based on the type of prosthetic valve used. The long-term mortality outcomes were then analyzed.

Results: During a median follow-up period of 59.6 months, the Kaplan–Meier survival analysis revealed that ESRD patients who underwent mechanical valve replacement had higher rates of all-cause mortality and CV deaths than those who underwent bioprosthetic valve replacement (Log-rank test, p = 0.03 and 0.02, respectively). Multivariable regression analyses demonstrated that ESRD patients who underwent bioprosthetic valve replacement had lower rates of all-cause mortality (p &lt; 0.001, hazard ratio: 0.88, 95% confidence interval: 0.82–0.93) and cardiovascular (CV) death (p &lt; 0.001, hazard ratio: 0.83, 95% confidence interval: 0.76–0.90) than those who had mechanical valve replacement.

Conclusion: Bioprosthetic valve replacement is significantly associated with lower rates of all-cause mortality and CV death in the ESRD population.

Hemodialysis vascular access affects heart function and outcomes: Tips for choosing the right access for the individual patient

Chronic kidney disease is associated with increased cardiovascular morbidity and mortality. A well-functioning vascular access is associated with improved survival and among the available types of vascular access the arterio-venous (AV) fistula is the one associated with the best outcomes. However, AV access may affect heart function and, in some patients, could worsen the clinical status. This review article focuses on the specific cardiovascular hemodynamics of dialysis patients and how it is affected by the AV access; the effects of an excessive increase in AV access flow, leading to high-output heart failure; congestive heart failure in CKD patients and the contraindications to AV access; pulmonary hypertension. In severe heart failure, peritoneal dialysis (PD) might be the better choice for cardiac health, but if contraindicated suggestions for vascular access selection are provided based on the individual clinical presentation. Management of the AV access after kidney transplantation is also addressed, considering the cardiovascular benefit of AV access ligation compared to the advantage of having a functioning AVF as backup in case of allograft failure. In PD patients, who need to switch to hemodialysis, vascular access should be created timely. The influence of AV access in patients undergoing cardiac surgery for valvular or ischemic heart disease is also addressed. Cardiovascular implantable electronic devices are increasingly implanted in dialysis patients, but when doing so, the type and location of vascular access should be considered.

5-Year Outcomes Comparing Surgical Versus Transcatheter Aortic Valve Replacement in Patients With Chronic Kidney Disease

OBJECTIVES

The aim of this study was to compare 5-year cardiovascular, renal, and bioprosthetic valve durability outcomes in patients with severe aortic stenosis (AS) and chronic kidney disease (CKD) undergoing transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR).

BACKGROUND

Patients with severe AS and CKD undergoing TAVR or SAVR are a challenging, understudied clinical subset.

METHODS

Intermediate-risk patients with moderate to severe CKD (estimated glomerular filtration rate <60 mL/min/m²) from the PARTNER (Placement of Aortic Transcatheter Valve) 2A trial (patients randomly assigned to SAPIEN XT TAVR or SAVR) and SAPIEN 3 Intermediate Risk Registry were pooled. The composite primary outcome of death, stroke, rehospitalization, and new hemodialysis was evaluated using Cox regression analysis. Patients with and without perioperative acute kidney injury (AKI) were followed through 5 years. A core laboratory-adjudicated analysis of structural valve deterioration and bioprosthetic valve failure was also performed.

RESULTS

The study population included 1,045 TAVR patients (512 SAPIEN XT, 533 SAPIEN 3) and 479 SAVR patients. At 5 years, SAVR was better than SAPIEN XT TAVR (52.8% vs 68.0%; P = 0.04) but similar to SAPIEN 3 TAVR (52.8% vs 58.7%; P = 0.89). Perioperative AKI was more common after SAVR than TAVR (26.3% vs 10.3%; P < 0.001) and was independently associated with long-term outcomes. Compared with SAVR, bioprosthetic valve failure and stage 2 or 3 structural valve deterioration were significantly greater for SAPIEN XT TAVR (P < 0.05) but not for SAPIEN 3 TAVR.

CONCLUSIONS

In intermediate-risk patients with AS and CKD, SAPIEN 3 TAVR and SAVR were associated with a similar risk for the primary endpoint at 5 years. AKI was more common after SAVR than TAVR, and SAPIEN 3 valve durability was comparable with that of surgical bioprostheses.

Cohort study: "Outcomes of kidney transplantation in patients with prosthetic heart valves"

The number of kidney transplant candidates with prosthetic heart valves (PHVs) is increasing. Yet, outcomes of kidney transplantation in these patients are still unclear. This is the first report of post-transplant outcomes in patients with PHVs at time of kidney transplantation. We conducted a matched cohort study among recipients from the multicentric and prospective DIVAT cohort to compare the outcomes in patients with left-sided PHVs at time of transplantation and a group of recipients without PHV matched according to age, dialysis time, initial disease, pretransplant DSA, diabetes, and cardiovascular events. Of 23 018 patients, 92 patients with PHVs were included and compared to 276 patients without PHV. Delayed graft function and postoperative bleeding occurred more frequently in patients with PHVs. Kidney graft survival was similar between groups. 5-year overall survival was 68.5% in patients with PHV vs. 87.9% in patients without PHV [HR, 2.72 (1.57-4.70), P = 0.0004]. Deaths from infection, endocarditis, and bleeding were more frequent in patients with PHV. Mechanical valves, but not bioprosthetic valves, were independent risk factors for mortality [HR, 2.89 (1.68-4.97), P = 0.0001]. Patients with PHV have high mortality rates after kidney transplantation. These data suggest that mechanical valves, but not biological valves, increase risks of post-transplant mortality.

Impact of dialysis in patients undergoing bioprosthetic aortic valve replacement

OBJECTIVES

To determine the incidence of bioprosthetic structural valve deterioration in dialysis patients undergoing aortic valve replacement compared to that in patients without dialysis.

METHODS

This single-centre retrospective observational study included 1159 patients who underwent aortic valve replacement using bioprosthetic valves for aortic stenosis and/or regurgitation at our institution between 2007 and 2017 [patients with dialysis (group D, n = 134, 12%) or without dialysis (group N, n = 1025, 88%)]. To adjust for potential differences between groups in terms of initial preoperative characteristics or selection bias, a propensity score analysis was conducted. The final sample that was used in the comparison included 258 patients, as follows: 129 patients with dialysis (group D) and 129 patients without dialysis (group N). The cumulative incidences of all-cause death, cardiac death and moderate or severe structural valve deterioration were estimated using the Kaplan-Meier method.

RESULTS

Operative mortality was significantly higher in group D than group N (9% vs 0%, P = 0.001). Kaplan-Meier analysis revealed that in group D, the incidence was significantly higher for all-cause death (P < 0.001, 50% vs 18% at 5 years), cardiac death (P = 0.001, 18% vs 5% at 5 years) and moderate or severe structural valve deterioration (P < 0.001, 29% vs 5% at 5 years) compared with group N.

CONCLUSIONS

The incidence of structural valve deterioration in dialysis patients undergoing aortic valve replacement was higher than that in patients without dialysis. Bioprosthetic valves should be carefully selected in dialysis patients undergoing aortic valve replacement.

Evaluation and Management of Aortic Stenosis in Chronic Kidney Disease: A Scientific Statement From the American Heart Association

Aortic stenosis with concomitant chronic kidney disease (CKD) represents a clinical challenge. Aortic stenosis is more prevalent and progresses more rapidly and unpredictably in CKD, and the presence of CKD is associated with worse short-term and long-term outcomes after aortic valve replacement. Because patients with advanced CKD and end-stage kidney disease have been excluded from randomized trials, clinicians need to make complex management decisions in this population that are based on retrospective and observational evidence. This statement summarizes the epidemiological and pathophysiological characteristics of aortic stenosis in the context of CKD, evaluates the nuances and prognostic information provided by noninvasive cardiovascular imaging with echocardiography and advanced imaging techniques, and outlines the special risks in this population. Furthermore, this statement provides a critical review of the existing literature pertaining to clinical outcomes of surgical versus transcatheter aortic valve replacement in this high-risk population to help guide clinical decision making in the choice of aortic valve replacement and specific prosthesis. Finally, this statement provides an approach to the perioperative management of these patients, with special attention to a multidisciplinary heart-kidney collaborative team-based approach.

In patients undergoing dialysis who require a valve replacement is a bioprosthetic valve superior to a mechanical prosthesis in terms of long-term survival and morbidity?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'In [dialysis patients undergoing a valve replacement] is [a bioprosthetic valve superior to a mechanical prosthesis] for [long-term survival and morbidity]'. Altogether more than 501 papers were found using the reported search, of which five represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. There was limited high-quality evidence with all studies being retrospective. One meta-analysis and four cohort studies provided the evidence that there was no significant difference in long-term survival based on prosthesis type. However, the majority of studies demonstrated a significantly higher rate of valve-related complications including bleeding and thromboembolism, and readmission to hospital in the mechanical valve prosthesis group, likely related to the requirement for long-term anticoagulation. We conclude that overall long-term survival in dialysis-dependent patients is poor. While prosthesis type does not play a significant contributing role to long-term survival, bioprosthetic valves were associated with significantly fewer valve-related complications. Based on the available evidence, a bioprosthetic valve may be more suitable in this high-risk group of patients as it may avoid the complications associated with long-term anticoagulation without any reduction in long-term survival.

Mechanical or biological heart valve for dialysis-dependent patients? A meta-analysis

OBJECTIVE

The optimal selection of prosthetic heart valve for dialysis-dependent patients remains controversial. We investigated the comparative effectiveness and safety of mechanical prosthesis (MP) and bioprosthesis (BP) for these patients.

METHODS

After the systematic review, we included studies that involved patients on dialysis undergoing aortic valve replacement or mitral valve replacement (MVR) and reported comparative outcomes of MP and BP. Meta-analysis was performed using random-effects model. We conducted a subgroup analysis based on the valve position and postoperative international normalized ratio (INR), which was extracted from either tables or methods of each study. A meta-regression was used to examine the effects of study-level covariates.

RESULTS

We included 24 retrospective studies without randomized-controlled trials, involving 10,164 participants (MP = 6934, BP = 3230). Patients undergoing aortic valve replacement with MP exhibited a better long-term survival effectiveness (hazard ratio, 0.64; 95% confidence interval [CI], 0.47-0.86). Conversely, studies including MVR demonstrated little difference in survival (hazard ratio, 0.90; 95% CI, 0.73-1.12). A meta-regression revealed that age had little effect on long-term survival difference between MP and BP (β = -0.0135, P = .433). MP had a significantly greater bleeding risk than did BP when INR was above 2.5 (incidence rate ratio, 10.58; 95% CI, 2.02-55.41). However, when INR was below 2.5, bleeding events were comparable (incidence rate ratio, 1.73; 95% CI, 0.78-3.82). The structural valve deterioration rate was significantly lower in MP (risk ratio, 0.24; 95% CI, 0.14-0.44).

CONCLUSIONS

MP is a reasonable choice for dialysis-dependent patients without additional thromboembolic risk requiring aortic valve replacement, for its better long-term survival, durability, and noninferior bleeding risk compared with BP. Conversely, BP might be an appropriate selection for patients with MVR, given its similar survival rate and lower bleeding risk. Although our meta-regression demonstrates little influence of age on long-term survival difference between MP and BP, further studies stratifying patients based on age cut-off are mandatory.

Surgical Therapy for Patients with Severe Aortic Stenosis in the Era of Transcatheter Aortic Valve Replacement

Aortic stenosis (AS) is the most common valvular heart disease and is most frequently recognized among elderly people. Surgical aortic valve replacement (SAVR) is the most effective therapy, but its indication is sometimes difficult, and is impossible for high operative risk patients. Transcatheter aortic valve replacement (TAVR) was recently approved in Japan for high risk and inoperable patients with severe AS. TAVR is a less invasive method because it does not require a cardiopulmonary bypass and is associated with excellent surgical outcomes. In Western countries, the indication of TAVR has already been extended to moderate operative risk patients with severe AS, and is going to be further extended to low risk patients. The number of patients undergoing TAVR is increasing progressively, and there are effective alternative therapies for patients with severe AS. Selection of these surgical methods will be important in the near future. In regard to low operative risk patients especially, not only operative mortality, but also long-tern mortality and morbidity and quality of life should be taken into consideration. It is considered that some comorbidities in AS patients will be revealed to have an impact on surgical outcomes at the time when these surgical methods are selected. In this review, we examine end-stage renal disease on hemodialysis, functional tricuspid regurgitation, and sigmoid septum, and give an outline of what influence SAVR and TAVR have on the surgical outcomes of severe AS patients.

Solo Smart stentless bioprosthesis for redo aortic valve replacement

BACKGROUND

In the redo aortic valve replacement (AVR), removal of the previously implanted damaged prosthesis may result in a native aortic annulus defect, making it difficult to reimplant a stented prosthesis. The Solo Smart valve, a relatively new stentless bioprosthesis, is designed for the supra-annular implantation into the wall of the sinus of Valsalva and may be a useful alternative to redo-AVR.

CASE REPORT

We report a successful case of redo-AVR using the Solo Smart valve.

CONCLUSION

The unique feature of the Solo Smart valve is the supra-annular implantation procedure in the sinus of Valsalva without annular stitches. This bioprosthesis can be a useful alternative for redo-AVR in patients with a defect of the native aortic annulus.

Mechanical versus bioprosthetic valves in patients on dialysis

Background

The aim of this study is to evaluate the outcomes of bioprosthetic versus mechanical valves in patients on dialysis.

Methods

All patients who underwent aortic (AVR) or mitral valve replacement (MVR) at a single institution from 2011-2017 were reviewed. Primary stratification was bioprosthetic versus mechanical valves. The primary outcome was all-cause mortality. Secondary outcomes included hospital readmission, valve reoperation rates and bleeding events. Kaplan-Meier curves were generated and Cox proportional hazards regression models were used for risk-adjustment.

Results

During the study period, 3,969 patients underwent AVR or MVR, of which 97 (2.4%) were on dialysis. In dialysis patients, unadjusted 30-day mortality was comparable between bioprosthetic (12.7%) versus mechanical (5.9%) valves (P=0.31). However, the bioprosthetic group had higher rates of 1-year (40.3% versus 15.2%; P=0.03) and 5-year mortality (67.9% versus 60.7%; P=0.02). Most patients were readmitted within 5 years with no differences between the groups (bioprosthetic 80.3% versus mechanical 100%; P=0.57). There were no valve reoperations in either group at 5 years. The 5-year readmission rate was higher in the mechanical cohort (10.5% versus 53.8%; P=0.05). Risk-adjusted analysis confirmed these findings, where mechanical valves were independently associated with reduced mortality at 1-year and 5-years.

Conclusions

Despite the limited life expectancy of patients on dialysis, mechanical valves have an intermediate term mortality benefit compared to bioprosthetic valves. This comes at the expense of a higher rate of readmission for bleeding. Although valve choice should consider multiple factors, these data suggest that mechanical valve usage in dialysis patients is reasonable.