Ten-year results of aortic valve replacement with first-generation Mitroflow bioprosthesis: is early degeneration a structural or a technical issue?

Three-year outcomes of surgical valve replacement with Dafodil™ pericardial bioprosthesis: Dafodil™-1 trial

Background

The Dafodil™-1 trial was designed to evaluate the clinical safety and performance of Dafodil™ pericardial bioprosthesis for replacing diseased native or prosthetic aortic or mitral valves in patients with advanced valvular heart disease (VHD).

Methods

The Dafodil™-1 trial was a prospective, multicenter, first-in-human clinical trial. Patients were enrolled if they had advanced VHD requiring aortic valve replacement (AVR) or mitral valve replacement (MVR) with or without concomitant valve surgery and having surgical risk scores <4%. Major adverse cardiac events (MACE), including all-cause death, myocardial infarction (MI), and stroke; and hemodynamics were analyzed.

Results

A total of 136 patients (aortic: 67 and mitral: 69) were enrolled in the trial (with mean age-AVR group: 60.2 ± 8.3 years and MVR group: 49.7 ± 14.4 years). A total of 134 patients (aortic: 66 and mitral: 68) completed the 3-year follow-up (total 300 per 100 patient-years of follow-up). The AVR group demonstrated a significant reduction in the mean pressure gradients from 51.2 ± 24.1 mmHg at baseline to 11.1 ± 6.0 mmHg at the 3-year follow-up (p < 0.0001). The mean effective orifice area (EOA) improved from baseline (0.9 ± 0.6 cm2) to 3-year follow-up (1.8 ± 0.4 cm2) (p < 0.0001). In the MVR group, the mean indexed EOA (iEOA) increased significantly from baseline (0.7 ± 0.4 cm2/m2) to 3-year follow-up (1.1 ± 0.4 cm2/m2) (p < 0.001). There was significant improvement in New York Heart Association functional class and mean SF-12 scores in both groups. At 3-year follow-up, the MACE incidence was 2.3% per 100 patient-years (1.3% strokes per 100 patient-years and 1.3% deaths per 100 patient-years) for AVR group and 4.7% per 100 patient-years (0.6% strokes per 100 patient-years and 4.0% deaths per 100 patient-years) for MVR group. No cases of MI, structural valve deterioration and prosthetic valve endocarditis were reported. The AVR and MVR groups achieved 89.6% and 79.7% MACE-free survival, respectively at 3-year follow-up.

Conclusions

The Dafodil™-1 trial demonstrated satisfactory outcomes of clinical safety, hemodynamic performance, and quality-of-life metrics. Additionally, no incidence of structural valve deterioration and very low rates of valve thrombosis during the 3-year follow-up period of Dafodil™-1 first-in-human trial indicated acceptable valve durability up to three years and similar outcomes are warranted for longer follow-ups as a primary goal.

Clinical Trial Registration Number

https://www.ctri.nic.in/Clinicaltrials/showallp.php?mid1=18377&EncHid=&userName=CTRI/2017/07/009008, CTRI/2017/07/009008.

5-Year haemodynamic performance of three aortic bioprostheses. A randomized clinical trial

OBJECTIVES

The Carpentier Perimount (CP) Magna Ease, the Crown Phospholipid Reduction Treatment (PRT) and the Trifecta bovine pericardial valves have been widely used worldwide. The primary end point of this study was to compare the haemodynamic performance quantified by in vivo echocardiograms of these 3 aortic prostheses.

METHODS

The "BEST-VALVE" (comparison of 3 contemporary cardiac bioprostheses: mid-term valve haemodynamic performance) was a single-centre randomized clinical trial to compare the haemodynamic and clinical outcomes of the aforementioned bioprostheses. The 5-year results are assessed in this manuscript.

RESULTS

A total of 154 patients were included. The CP Magna Ease (n = 48, 31.2%), Crown PRT (n = 51, 32.1%) and Trifecta (n = 55, 35.7%) valves were compared. Significant differences were observed among the 3 bioprostheses 5 years after the procedure. The following haemodynamic differences were found between the CP Magna Ease and the Crown PRT bioprostheses [mean aortic gradient: 12.3 mmHg (interquartile range {IQR} 7.8-17.5) for the CP Magna Ease vs 15 mmHg (IQR 10.8-31.9) for the Crown PRT, P < 0.001] and between the CP Magna Ease and the Trifecta prostheses [mean aortic gradient: 12.3 mmHg (IQR 7.8-17.5) for the CP Magna Ease vs 14.7 mmHg (IQR 8.2-55) for the Trifecta, P < 0.001], with a better haemodynamic performance of the CP Magna Ease. The cumulative incidence of severe structural valve degeneration was 9.5% in the Trifecta group at 6 years of follow-up. The 1-, 3- and 5-year survival from all-cause mortality was 91.5%, 83.5% and 74.8%, respectively (log rank P = 0.440). Survival from the composite event at the 1-, 3- and 5-year follow-up was 92.8%, 74.6% and 59%, respectively (log rank P = 0.299).

CONCLUSIONS

We detected significant differences between the 3 bioprostheses; the CP Magna Ease had the best haemodynamic performance at the 5-year follow-up.

Excess Reintervention With Mitroflow Prosthesis for Aortic Valve Replacement: Ten-Year Outcomes of a Randomized Trial

BACKGROUND

Current bioprostheses are considered to have improved durability and better hemodynamic performance compared with previous designs, but there are limited comparative data on late outcomes.

METHODS

From 2009 through 2011, 300 adults with severe aortic valve stenosis undergoing aortic valve replacement (AVR) were randomly assigned to receive Edwards Magna, St Jude Epic, or Sorin Mitroflow bioprostheses (n = 100, n = 101, n = 99, respectively). Overall survival was analyzed using Kaplan-Meier and Cox proportional hazards methods, whereas competing risk analysis was used for all time-to-event outcomes. Serial echocardiographic data were fitted with longitudinal models stratified by implant valve size.

RESULTS

During median follow-up of 9.8 years (interquartile range, 8.7-10.2), 10-year survival was 50% for the Magna group, 42% for the Epic group, and 41% for the Mitroflow group (P = .415). Cumulative risk of stroke was 9% at 10 years, and rates were comparable for the three groups. Indexed aortic valve area and mean gradients were similar among the three groups receiving 19 mm and 21 mm valves, but in larger (23 mm or more) prostheses, gradients were lower (P < .001) and indexed aortic valve areas were higher in the Magna group (P < .001). The 10-year risk of endocarditis differed by group (P = .033), with higher incidence in the Mitroflow vs the Magna group (7% vs 0%, P = .019). Late risk of reinterventions in the Mitroflow group was 22%, compared with 0% in the Magna group (P < .001) and 5% in the Epic group (P = .008).

CONCLUSIONS

The Magna valve had the lowest gradients and largest indexed aortic valve area with larger implant sizes. The Mitroflow bioprosthesis is associated with an increased rate of reintervention and possible increased risk of infection compared with Magna and Epic valves.

Hemodynamic and Mid-Term Outcomes for Transcatheter Aortic Valve Replacement in Degenerated Internally Stented Valves

BACKGROUND

Valve-in-valve (ViV) transcatheter aortic valve replacement is indicated in patients undergoing repeat intervention for degenerative aortic valve bioprostheses. Patients with internally stented valves (ie, Mitroflow and Trifecta) are at high risk for coronary artery obstruction during ViV procedures because of valve design, as the leaflets are mounted outside the valve stent.

OBJECTIVES

The aim of this study was to compare the hemodynamic and clinical outcomes of transcatheter aortic valve replacement within internally stented valves (ViV-IS) vs other surgical valves (ViV-OS).

METHODS

Baseline characteristics, hemodynamic parameters, and clinical outcomes of patients who underwent ViV-IS were retrospectively collected and compared with those of patients who underwent ViV-OS.

RESULTS

A total of 250 patients (65% men, median Society of Thoracic Surgeons score 4.4% [IQR: 2.2%-8.4%]) were included. Seventy-one patients (28%) underwent ViV-IS, and 179 (72%) patients underwent ViV-OS. Patients who underwent ViV-OS had better periprocedural hemodynamic status compared with those who underwent ViV-IS (median mean gradient 6 [IQR: 2-13] vs 12 [IQR: 6-16]; P < 0.001). This was not significantly different when both groups were matched on the basis of age, sex, and valve internal diameter size (median mean gradient: 18 [IQR: 13-25] for ViV-OS vs 18 [IQR: 11-24] for ViV-IS; P = 0.36). Coronary protection for potential occlusion was performed more in ViV-IS vs ViV-OS pr (79% vs 6%, respectively; P < 0.001). Patients who underwent ViV-IS had a higher risk for coronary occlusion, requiring stent deployment, compared with those who underwent ViV-OS (54% vs 3%, respectively; P < 0.001. There was no difference in mortality at 3 years between the 2 groups (P = 0.59).

CONCLUSIONS

Patients who underwent ViV-IS had a very high incidence of coronary compromise that can be safely and effectively treated. In the setting of a systematic coronary protection strategy, ViV-OS and ViV-IS provide similar mid-term outcome, and periprocedural hemodynamic status (following adjustment for age, sex, and true internal diameter).

The pathology of early failure in Mitroflow pericardial valve bioprosthesis (12A/LX)

BACKGROUND

Limited mid-term durability of 12A/LX Mitroflow bioprosthesis has been reported. Aim of the study was to ascertain the pathologic substrates and possible mechanisms of structural valve deterioration in explants from animals and humans.

METHODS

Nine aortic 12A/LX Mitroflow bioprostheses preserved in hypotonic solution and three aortic 12A/LX bioprostheses, preserved in isotonic solution, were explanted from juvenile sheep, mean time from implant 95.66 ± 36.04 days and 132.33 ± 28.88 days from implant respectively. One stented unimplanted 12A/LX Mitroflow preserved in isotonic colution before glutaraldeyde fixation served as control. Ten aortic 12A/LX Mitroflow bioprostheses were explanted from humans because of severe dysfunction: five children, (3 females and 2 males, mean age 14.19 ± 4.77 years, range 11-21), 26 ± 8.24 months from implant and 5 adults (4 females and 1 male, mean age 57.4 ± 19.85 years, range 31-72), 64.4 ± 26.94 months from implant. X-ray, histology, and transmission electron microscopy were carried out as well as spectroscopy for calcium (Ca++) and phosphorus (P) content in human explants.

RESULTS

Explants, from both animals and humans, showed cusp folding and stiffness, with coarse calcific deposits at gross examination and X-ray. Severe collagen denaturation, plasma insudation and massive calcification, involving both collagen and cell debris, were observed microscopically. Mean Ca++ content of 183.27 ± 62.48 and P content of 94.35 ±33.76 mg/g dry weight was found in children and Ca++ content of 205.49 ± 2.23 and P content of 99.75 ± 0.11 mg/g dry weight in adults. Obstructive fibrous tissue overgrowth was detected in 6 human cases.

CONCLUSIONS

Collagen denaturation was observed in pericardial Mitroflow 12A/LX bioprosthesis with premature structural valve deterioration. Optimal collagen fixation and preservation as well as phospholipids reduction by removing cell debris, as employed in the novel CROWN PRT Mitroflow bioprosthesis, are expected to solve the flaw and achieve long-term durability.

Redo aortic valve intervention after transcatheter aortic valve replacement: Analysis of the nationwide readmission database

BACKGROUND

Outcomes of redo aortic valve intervention (AVI) following transcatheter aortic valve replacement (TAVR) have not been well described. We thought to investigate the incidence, predictors, and outcomes of redo AVI after TAVR.

METHODS

The Nationwide Readmission Database (from 2012 to 2017) was queried to identify admissions for TAVR. Redo AVI was defined as readmissions that required either TAVR or balloon aortic valvuloplasty (BAV) or surgical aortic valve replacement (SAVR). A multivariable regression model was used to identify independent predictors of redo AVI. In-hospital outcomes of redo TAVR or BAV and redo SAVR were compared in the unadjusted model.

RESULTS

A total of weighted 148,200 (unweighted redo AVI 297, no redo AVI 73,804) index TAVRs were identified. A weighted 593 (435 TAVR or BAV and 158 SAVR) redo AVI was included with an incidence of 1.0 per 100 person-year during a median of 105 (interquartile range 41-195) days follow-up. Predictors of redo AVI were female, heart failure, obesity, atrial fibrillation, transapical approach, oral anticoagulant use, and acute kidney injury. In-hospital mortality of redo AVI was 7.6% (5.3% for redo TAVR or BAV vs. 13.8% for redo SAVR, unadjusted p = 0.10). Stroke, myocardial infarction, bleeding requiring transfusion, new pacemaker, and acute kidney injury rates were 4.7%, 2.6%, 9.3%, 10.0%, and 31.2%, respectively in redo AVI. Length of stay and hospital cost was 4.8 days and 55,826 U.S. dollars, respectively.

CONCLUSIONS

The incidence of redo AVI was low following TAVR but was associated with high mortality and morbidities.

[Safety of biological valves for aortic valve replacement: A systematic review and meta-analysis]

OBJECTIVE

To provide a comprehensive and contemporary overview of the long-term safety outcomes after aortic valve replacements (AVR) with conventional biological heart valve (stented or stentless).

METHODS

English databases (Medline, Embase, Web of Science, CENTRAL, and ClinicalTrial.gov) and Chinese databases (CNKI, VIP, WanFang, and SinoMed) were searched systemically from January 1, 2000 to January 26, 2019. Eligible randomized controlled trials, non-randomized clinical trials, cohort studies (retrospective or prospective), and unselected case series were included. Strict screening of the obtained literature was conducted to extract relevant data by two reviewers. Other inclusion criteria were studied reporting on outcomes of AVR with biological valves (stented or stentless), with or without coronary artery bypass grafting (CABG) or valve repair procedure, with mean follow-up length equal to or longer than 5 years. We excluded studies that reported only a specific patient group (e.g., patients with renal failure, or pregnancy), without the report of biological valve type, or with study population size less than 100. The meta-analysis was performed using Stata 14.0 software.

RESULTS

In this study, 53 papers (in total 57 study groups) involving 47 803 patients were included. (1) The all-cause mortality was 6.33/100 patient-years (95%CI: 5.85-6.84). Subgroup analysis showed that the mortality rates of porcine and bovine valve prostheses were 5.69/100 patient-years (95%CI: 5.05-6.41) and 7.29/100 patient-years (95%CI: 6.53-8.13), respectively. The all-cause mortality rates for stented and stentless valve were 6.69/100 patient-years (95%CI: 6.12-7.30) and 5.21/100 patient-years (95%CI: 4.43-6.14), respectively. (2) The incidence rate of thromboembolism was 1.16/100 patient-years (95%CI: 0.96-1.40), the incidence rate of permanent pacemaker (PPM) implantation was 1.08/100 patient-years (95%CI: 0.75-1.54), the incidence rate of stroke was 0.74/100 patient-years (95%CI: 0.51-1.06), the incidence rate of structural valve dysfunction (SVD) was 0.73/100 patient-years (95%CI: 0.59-0.91), the incidence rate of major bleeding was 0.52/100 patient-years (95%CI: 0.41-0.65), the incidence rate of endocarditis was 0.38/100 patient-years (95%CI: 0.33-0.44), and the incidence rate of non-structural valve dysfunction (NSVD) was 0.20/100 patient-years (95%CI: 0.13-0.31). The total reoperation rate for biological aortic valve was 0.77/100 patient-years (95%CI: 0.65-0.91), and the SVD related reoperation rate was 0.46/100 patient-years (95%CI: 0.36-0.58).

CONCLUSION

The all-cause mortality for conventional biological AVR was 6.33/100 patient-years. Thromboembolism, PPM implantation, reoperation, stroke, and SVD were major long term complications.

Age-Related 2-Year Mortality After Transcatheter Aortic Valve Replacement: the YOUNG TAVR Registry

OBJECTIVE

To comparatively assess the natural history of patients of different ages undergoing transcatheter aortic valve replacement (TAVR).

PATIENTS AND METHODS

For this study, we used the YOUNG TAVR, an international, multicenter registry investigating mortality trends up to 2 years in patients with aortic valve stenosis treated by TAVR, classified according to 3 prespecified age groups: 75 years or younger (n=179), 76 to 86 years (n=602), and older than 86 years (n=221). A total of 1002 patients undergoing TAVR were included. Demographic, clinical, and outcome data in the youngest group were compared with those of patients 76 to 86 years and older than 86 years. Patients were followed up for up to 2 years.

RESULTS

Compared with patients 75 years or younger (reference group), patients aged 76 to 86 years and older than 86 years had nonsignificantly different 30-day mortality (odds ratio, 0.76; 95% CI, 0.41-1.38; P=.37 and odds ratio, 1.27; 95% CI, 0.62-2.60; P=.51, respectively) and 1-year mortality (hazard ratio (HR), 0.72; 95% CI, 0.48-1.09; P=.12 and HR, 1.11; 95% CI, 0.88-1.40; P=.34, respectively). Mortality at 2 years was significantly lower among patients aged 76 to 86 years (HR, 0.62; 95% CI, 0.42-0.90; P=.01) but not among the older group (HR, 1.06; 95% CI, 0.68-1.67; P=.79). The Society of Thoracic Surgeons 30-day mortality score was lower in younger patients who, however, had a significantly higher prevalence of chronic obstructive pulmonary disease (P=.005 vs the intermediate group and P=.02 vs the older group) and bicuspid aortic valves (P=.02 vs both older groups), larger left ventricles, and lower ejection fractions.

CONCLUSION

In the present registry, mortality at 2 years after TAVR among patients 75 years or younger was higher compared with that of patients aged 75 to 86 years and was not markedly different from that of patients older than 86 years. The findings are attributable at least in part to a greater burden of comorbidities in the younger age group that are not entirely captured by current risk assessment tools.