Intermediate-term outcomes of aortic valve replacement with bioprosthetic or mechanical valves in patients on hemodialysis

Five-Year Transcatheter Aortic Valve Replacement Outcomes in Chronic Hemodialysis vs. Non-Hemodialysis Patients Using Balloon-Expandable Devices

BACKGROUND

Based on the results of a clinical trial in Japan, transcatheter aortic valve replacement (TAVR) for hemodialysis (HD) patients gained approval; however, mid-term TAVR outcomes and transcatheter aortic valve (TAV) durability in HD patients remain unexplored.Methods and Results: We analyzed background, procedural, in-hospital outcome, and follow-up data for 101 HD patients and 494 non-HD patients who underwent TAVR using balloon-expandable valves (SAPIEN XT or SAPIEN 3) retrieved from Osaka University Hospital TAVR database. Periprocedural mortality and TAVR-related complications were comparable between HD and non-HD patients. However, Kaplan-Meier analysis revealed that HD patients had significantly lower survival rates (log-rank test, P<0.001). In addition, HD patients had significantly higher rates of severe structural valve deterioration (SVD) than non-HD patients (Gray test, P=0.038).

CONCLUSIONS

TAVR in HD patients had comparable periprocedural mortality but inferior mid-term survival and TAV durability than in non-HD patients. Indications for TAVR in younger HD patients should be carefully determined, considering the possibility of a TAV-in-TAV procedure when early SVD occurs.

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.

Mid-term results of surgical aortic valve replacement with bioprostheses in hemodialysis patients

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HD patients underwent SAVR-BP for AS (hospital mortality, 8.8%; 5-year mortality, 42.1%).

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Preoperative risk factors for 5-year mortality: age, hyperlipidemia, LVDd, LVDs, and Japan SCORE.

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Postoperative risk factors for 5-year mortality: length of ICU stay, and albumin level at discharge.

Background

Limited studies have assessed the factors affecting prognosis in hemodialysis (HD) patients who undergo surgical aortic valve replacement with a bioprostheses (SAVR-BP). This study aimed to evaluate the outcomes of HD patients who had undergone SAVR-BP for aortic stenosis (AS) and identify the risk factors for mortality.

Methods

This retrospective study included 57 HD patients who had undergone SAVR-BP for AS between July 2009 and December 2020. Multivariate logistic regression was used to predict factors associated with mid-term outcomes and death or survival. Kaplan − Meier curves were also generated for mid-term survival.

Results

The in-hospital mortality rate was 8.8%, and the 5-year mortality rate was 42.1%. The independent predictors of 5-year mortality were preoperative age (hazard ratio [HR], 1.57; 95% confidence interval [CI], 1.175–2.083, p = 0.002), hyperlipidemia (HR, 0.02; 95% CI, 0.002–0.297, p = 0.004), left ventricular diastolic diameter (HR, 1.74; 95% CI, 1.142–2.649, p = 0.010), left ventricular systolic diameter (HR, 0.61; 95% CI, 0.392–0.939, p = 0.025), and Japan SCORE (HR, 1.28; 95% CI, 1.052–1.563, p = 0.014). The postoperative predictors included intensive care unit stay (HR, 1.11; 95% CI, 1.035–1.194, p = 0.004) and albumin level (HR, 0.38; 95% CI, 0.196–0.725, p = 0.003).

Conclusions

The 5-year prognosis of HD patients undergoing SAVR may be improved by early diagnosis (before the occurrence of LV hypertrophy/enlargement) and nutritional management with oral intake to alleviate postoperative hypoalbuminemia.

Registration number of clinical studies: UMIN000047410.

Strict control of phosphorus concentration of hemodialysis patients may decrease structural valve deterioration after aortic valve replacement

OBJECTIVES

The number of hemodialysis patients requiring aortic valve replacement (AVR) is increasing. Although bioprosthetic valves are increasingly popular, they are associated with a risk of structural valve deterioration (SVD). The aim of this study is to examine the outcomes of bioprosthetic valves in hemodialysis patients undergoing AVR and to identify treatment strategies that can decrease the risk of SVD.

METHODS

Between February 2010 and November 2019, 61 patients on hemodialysis underwent AVR using bioprosthetic valves at our hospital. Five patients died while still in the hospital. Kaplan-Meier estimates of overall survival and univariate Cox proportional hazards regression analyses were performed for the remaining 56 patients.

RESULTS

During follow-up, there were six SVD events (10.7%) related to the bioprosthetic valves. The survival rate was 67.9% at 3 years and 39.5% at 5 years. In all SVD cases, SVD was caused by aortic stenosis. The mean interval between AVR and the discovery of SVD was 41.5 months. The SVD-free rate was 88.6% at 3 years and 65.3% at 5 years. Preoperative phosphorus levels are associated with SVD risk. High preoperative phosphorus concentration is associated with elevated SVD risk.

CONCLUSIONS

In this study, we determined that the risk of SVD can be influenced by preoperative phosphorus level. Strict control of the phosphorus concentration of hemodialysis patients may decrease structural valve deterioration after aortic valve replacement.

Surgical outcomes of minimally invasive aortic valve replacement via right mini-thoracotomy for hemodialysis patients

OBJECTIVES

Minimally invasive valve surgery has become increasingly accepted as an alternative to conventional median sternotomy in low-risk patients. However, there have been no reports regarding the outcomes of this procedure on high-risk hemodialysis patients. The purpose of this investigation was to assess the surgical outcomes of minimally invasive aortic valve replacement (AVR) via right mini-thoracotomy (MIAVR) in hemodialysis patients compared with those of conventional AVR (CAVR) via full sternotomy.

METHODS

Two hundred and seventy-four patients underwent isolated AVR for severe AS, and 42 hemodialysis patients were included in this study. MIAVR was performed in 17 cases and CAVR in 25 cases. We compared the short-term surgical outcome among the two groups.

RESULTS

There was no difference in the aortic cross-clamp or cardiopulmonary bypass time. However, the procedure time was significantly shorter in the MIAVR group. Patients in the MIAVR group had less bleeding and a smaller amount of transfused red blood cells. There were four hospital deaths (18.2%) in the CAVR group. For postoperative complications, there were 2 (9.1%) cerebrovascular incidents, 2 (9.1%) cases of respiratory failure, 1 (4.5%) re-exploration for bleeding in CAVR group. The postoperative ventilation time was significantly shorter in the MIAVR group. There was no difference in the length of postoperative intensive care unit stay or of postoperative hospital stay.

CONCLUSION

The surgical outcomes of MIAVR in hemodialysis patients were acceptable, with a low incidence of morbidity, reasonable lengths of hospital stay, and no mortality among the patients studied.

Longitudinal Hemodynamics of Aortic Bioprosthetic Valve in Hemodialysis Patients

We examined the hemodynamic profile of bioprosthetic aortic valves in patients on hemodialysis (HD), longitudinally, and assess the incidence of adverse changes detected by echocardiography. Of 1,146 consecutive patients with severe aortic stenosis who underwent bioprosthetic aortic valve replacement (AVR), 148 patients had end-stage renal disease requiring HD. Each patient on HD was matched one-to-one with a non-HD patient on the basis of propensity scores. The mean follow-up period was 3.3 years for the HD group and 5.9 years for the non-HD group. Follow-up information was available for 95.2%. Postoperative trends of valve hemodynamics derived from linear mixed-effect models showed significant group vs time interactions between the two groups. Stable hemodynamics was consistently observed in the non-HD group, whereas the HD group showed a decrease of -0.06 cm²/y (95% confidence interval (CI), -0.10 to -0.02) in effective orifice area, an increase of 0.8 mm Hg/year (95% CI, 0.4-1.1) in mean pressure gradient, and an increase of 0.08 m/s/year (95%CI, 0.02-0.13) in peak velocity. Cumulative incidence function of SVD more than stage 2 was significantly higher in the HD group (13.1% vs 3.1% at 5 years, Gray test p = 0.01). In a multivariable Fine-Gray analysis, diabetes was independently associated with SVD more than stage 2 in the HD group (subhazard ratio, 1.91; 95% CI, 1.25-2.89; p = 0.02). Survival free-from stenotic-type SVD was significantly lower in HD patients undergoing bioprosthetic AVR. Diabetes was independently associated with postoperative stenotic-type SVD in HD patients.

Outcomes in Patients With Chronic Renal Failure on Hemodialysis After Aortic Valve or Root Replacement

The long-term survival and reoperation rate in chronic renal failure (CRF) on hemodialysis (HD) patients after aortic valve/root replacement (AVR/ARR) with a stentless bioprosthesis is unknown. From 1992-2015, 1941 patients underwent AVR/ARR with stentless valve for primary indications of aortic stenosis/insufficiency, root aneurysm, and acute type A aortic dissection, including 93 CRF-HD (64 new-onset postoperative HD, and 29 preoperative HD) and 1848 non-CRF-HD. Data was obtained from the STS database, retrospective chart review, administered surveys and national death index data. Compared to the non-CRF-HD group, the CRF-HD group had significantly higher incidence of diabetes mellitus (28 vs 18%), CAD (49 vs 38%), COPD (31 vs 16%), NYHA class IV (12 vs 4%), atrial fibrillation (24 vs 12%), and previous cardiac surgery (27 vs 16%). Postoperatively, CRF-HD group had a higher reoperation for bleeding (10 vs 4%), length of hospital stays (20 vs 7 days), and operative mortality (23 vs 2.3%), all p < 0.01. The odds ratio of CRF-HD for operative mortality was 8.97. The long-term survival was worse in CRF-HD group than that in non-CRF-HD group [8-year survival: 31% vs 70%, p < 0.0001]. The hazard ratio of CRF-HD for long-term mortality was 2.4. The 10-year cumulative reoperation rate for structural valve deterioration in the CRF-HD group was 6.0% vs 5.0% in the non-CRF-HD group, p = 0.74. Surgeons should consider poor short- and long-term outcomes of patients with high risk of being on dialysis when offering aortic valve/root replacement. Bioprosthesis could be a good option in this patient population.

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.

Management of Aortic Stenosis in Patients With End-Stage Renal Disease on Hemodialysis

BACKGROUND

Patients with end-stage renal disease on hemodialysis (ESRD-HD) and aortic stenosis have poor prognosis. The role of transcatheter aortic valve replacement (TAVR) in this high-risk population is debated.

METHODS

We compared the outcomes among ESRD-HD Medicare beneficiaries who were managed with TAVR, surgical AVR (SAVR), or conservative management for aortic stenosis between 2015 and 2017, using overlap propensity score weighting analysis to control for differences in treatment assignment. The primary outcome was all-cause mortality and was compared between treatment groups as well as to age-sex matched mortality for ESRD-HD in the US population. Secondary outcomes included trend of heart failure hospitalizations.

RESULTS

A total of 8107 ESRD-HD patients with aortic stenosis were included, 4130 (50%) underwent TAVR, 2565 (31.6%) underwent SAVR, and 1412 (17.4%) were managed conservatively. TAVR patients had more comorbidities and higher frailty compared with the other 2 groups. Thirty-day mortality was lower with TAVR compared with SAVR (4.6% versus 12.8%, P<0.01). After a median follow-up of 465 days (interquartile range, 261-759), on overlap propensity score weighting analysis, there was no difference in mortality between TAVR and SAVR (adjusted hazard ratio, 1.02 [95% CI, 0.91-1.15], P=0.7), and mortality was lower with TAVR compared with conservative management (adjusted hazard ratio, 0.53 [95% CI, 0.47-0.60], P<0.001). Standardized mortality ratios with TAVR, SAVR, and conservative management compared with age-sex matched ESRD-HD US population were 1.24, 1.27, and 1.83, respectively. The rate of heart failure admissions declined after TAVR (incidence rate ratio, 0.55 [95% CI, 0.48-0.62], P<0.001) and SAVR (incidence rate ratio, 0.76 [95% CI, 0.65-0.88], P<0.001).

CONCLUSIONS

In ESRD-HD patients with aortic stenosis, mortality was lower in the short-term with TAVR compared with SAVR but comparable in the mid-term. AVR is associated with an improvement in survival and reduction in heart failure hospitalizations compared with conservative management.

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.