A prospective, randomized comparison of 3 contemporary bioprosthetic aortic valves: Should hemodynamic performance influence device selection?

Porcine bioprostheses for surgical aortic valve replacement: very long-term performance of a third-generation device

AIMS

We aimed at investigating the long-term durability of the Epic bioprosthesis for surgical aortic valve replacement (SAVR) in a single-centre series of 888 implantations (2001-2018), expanding previous evaluations with shorter follow-up.

METHODS

We retrieved prospectively collected in-hospital data and performed a systematic follow-up focusing on valve-related events (SVD, structural valve deterioration; PPM, patient-prosthesis mismatch; reoperation) (competing risks, CIF and Kaplan--Meier methods). We distinguished between SVD (permanent changes in valve function due to evolutive structural deterioration, ≥10 mmHg average gradient vs. reference echocardiography) and PPM.

RESULTS

Average age at SAVR was 75.4 ± 7 years; 855 (96.3%) bioprostheses entered the follow-up and 396 (46.4%) were alive at last assessment. Follow-up was 99.9% complete, median duration was 7.7 years (entire cohort) and 9.9 years (survivors). At 10 years, overall survival was 50% ± 1.9, freedom from SVD was 99.4% ± 0.3 (competing risks) (seven SVD events after 8.1 ± 4.3 years). Freedom from SVD at 15 years was 98.4% ± 0.8 (competing risks). Prevalence of severe PPM was higher in 19 mm (6.5%) and 21 mm (10.2%) size cohorts. PPM (severe or moderate/severe) had no significant impact on overall survival (log-rank P = 0.27 and P = 0.21, respectively). Freedom from any reintervention (reoperation or TAVI Valve-in-Valve) for SVD at 10 years was 99.4% ± 0.3 (competing risks); freedom from any valve-related reintervention was 97.4% ± 0.6 (competing risks).

CONCLUSION

The Epic bioprosthesis for SAVR is limited by nonnegligible rates of PPM, which have nonetheless no impact on late survival. This device shows excellent durability and low rates of adverse valve-related events.

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.

Structural valve deterioration of bioprosthesis in the aortic position: A single-center experience

BACKGROUND

Aortic valve replacement (AVR) is one of the most common open-heart surgical procedures. The durability of the tissue valve in the aortic position is crucial in AVR and transcatheter AVR. We reviewed structural valve deterioration using echocardiographic follow-up in three types of surgical aortic tissue valves.

METHODS

A retrospective analysis was conducted where hemodynamic deterioration was evaluated and compared using transthoracic echocardiography, including pressure gradients and effective orifice area. Kaplan-Meier analyses were used to summarize the time to failure.

RESULTS

The study included 133 Trifecta, 156 Epic, and 321 Magna Ease valves. Seventy-six percent (1941/2551) of patients had to be excluded due to insufficient echo data. Through univariate analysis, 34% (216/610) of valves met deterioration criteria after 24 months. Unadjusted survival curves showed a significant difference between valves (p ≤ .001), with a longer mean time to deterioration for the Magna Ease versus Trifecta and Epic of 68.9 versus 50.1 and 38.2 months, respectively. A Cox proportional hazard analysis found worse hazard ratios of 1.69 (p ≤ .04) and 2.4 (p ≤ .01) for Trifecta versus Magna and Epic versus Trifecta, respectively.

CONCLUSION

All three valve types demonstrated structural valve deterioration on echocardiographic follow-up with significant differences in rate. The Magna Ease appeared to have the highest durability, and the Epic the lowest. Further investigation is warranted to confirm the results in a larger multicenter study.

Less invasive aortic valve replacement using the trifecta bioprosthesis

Objectives. The safety and effectiveness of the Trifecta GT bioprosthesis (introduced in 2016) in less invasive aortic valve replacement are scarcely investigated. Our aim was to evaluate the immediate and initial follow-up results of this device in the context of less invasive surgery. We discuss patient-specific strategies for the selection of the surgical approach. Methods. A retrospective review of 133 patients undergoing AVR with the Trifecta GT through three less invasive accesses (UMS, Upper ministernotomy; RMS, Reversed ministernotomy; RAMT, Right anterior minithoracotomy) was performed. In-hospital, follow-up and hemodynamic performance (PPM, Patient-prosthesis mismatch) data were collected. Results. Among patients, 79% received UMS, 11% RMS and 10% RAMT. Selection of approach was based on preoperative anatomical analysis (CT-scan) and planned concomitant procedures. There was no operative mortality, no valve-related adverse events. There were 36 concomitant procedures. No significant intergroup differences occurred in cardiopulmonary bypass, aortic clamp, mechanical ventilation time, ICU stay and average bleeding. There were two cases of moderate PPM (1.5%) and no instances of severe PPM; there were no significant (≥2/4) perivalvular leaks. Average mean gradient at discharge was 8 ± 3 mmHg. At follow-up (average: 2.5 ± 0.9 years, 100% complete, 315 patient years) there was no mortality and no valve-related adverse event. Hemodynamic performance was maintained at follow-up. Conclusions. The optimal device for less invasive AVR needs to be individualized, as well as the selection of the surgical approach. The use of the Trifecta GT bioprosthesis appears to be reproductible whatever less invasive approach is employed, with confirmed excellent hemodynamic performance.

One-Year Hemodynamic Performance of Three Cardiac Aortic Bioprostheses: A Randomized Comparative Clinical Trial

Background: We aimed to compare 1 year the hemodynamic in-vivo performance of three biological aortic prostheses (Carpentier Perimount Magna Ease^TM, Crown PRT^TM, and Trifecta^TM). Methods: The sample used in this study comes from the “BEST-VALVE” clinical trial, which is a phase IV single-blinded randomized clinical trial with the three above-mentioned prostheses. Results: 154 patients were included. Carpentier Perimount Magna Ease^TM (n = 48, 31.2%), Crown PRT^TM (n = 51, 32.1%) and Trifecta^TM (n = 55, 35.7%). One year after the surgery, the mean aortic gradient and the peak aortic velocity was 17.5 (IQR 11.3–26) and 227.1 (IQR 202.0–268.8) for Carpentier Perimount Magna Ease^TM, 21.4 (IQR 14.5–26.7) and 237.8 (IQR 195.9–261.9) for Crown PRT^TM, and 13 (IQR 9.6–17.8) and 209.7 (IQR 176.5–241.4) for Trifecta^TM, respectively. Pairwise comparisons demonstrated improved mean gradients and maximum velocity of Trifecta^TM as compared to Crown PRT^TM. Among patients with nominal prosthesis sizes ≤ 21, the mean and peak aortic gradient was higher for Crown PRT^TM compared with Trifecta^TM, and in patients with an aortic annulus measured with metric Hegar dilators less than or equal to 22 mm. Conclusions: One year after surgery, the three prostheses presented a different hemodynamic performance, being Trifecta^TM superior to Crown PRT^TM.

Computed Tomography Annular Dimensions: A Novel Method to Compare Prosthetic Valve Hemodynamics

BACKGROUND

The Cardiac Surgical Societies Valve Labeling Task Force consensus document acknowledged inconsistent sizing and labeling of prosthetic heart valves. This study compared the labeled size, internal diameter, and hemodynamics of different surgical and transcatheter valve types implanted into the same size annulus, measured by preprocedural computed tomography (CT).

METHODS

Patients were retrospectively sorted into 3 CT annular diameter size groups: small (less than 23 mm), medium (23 to less than 26 mm), and large (26 mm or greater). Surgical valves were sorted into 4 categories based on tissue and design: (stentless porcine, standard stented bovine, wraparound stented bovine, and stented porcine). Comparisons were made within the surgical types and with a transcatheter valve. Echocardiograms were independently assessed and CTs were centrally measured.

RESULTS

We analyzed 726 surgical and 923 transcatheter valve paired data sets. Among the various valve types implanted into the same size CT annulus, there were significant differences regarding size, internal diameter, and hemodynamics within all 3 size groups. Root enlargement procedures occurred in 1.2% with no differences across valve types or size groups. Transcatheter valve hemodynamics were similar to stentless valves and were significantly better than all stented valves. There was no difference in hemodynamics between the 2 bovine stented valve types, and stented porcine valves were inferior to all valve types.

CONCLUSIONS

This study documents that prosthetic heart valve sizing and labeling inconsistencies exist. Use of preoperative CT annular dimensions is the most accurate method to compare size, internal diameter, and hemodynamics of bioprosthetic aortic valves because it compares values among various valve types implanted into the same size annulus.

4D Flow MRI hemodynamic benchmarking of surgical bioprosthetic valves

PURPOSE

We exploited 4-dimensional flow magnetic resonance imaging (4D Flow), combined with a standardized in vitro setting, to establish a comprehensive benchmark for the systematic hemodynamic comparison of surgical aortic bioprosthetic valves (BPVs).

MATERIALS AND METHODS

4D Flow analysis was performed on two small sizes of three commercialized pericardial BPVs (Trifecta™ GT, Carpentier-Edwards PERIMOUNT Magna and Crown PRT®). Each BPV was tested over a clinically pertinent range of continuous flow rates within an in vitro MRI-compatible system, equipped with pressure transducers. In-house 4D Flow post-processing of the post-valvular velocity field included the quantification of BPV effective orifice area (EOA), transvalvular pressure gradients (TPG), kinetic energy and viscous energy dissipation.

RESULTS

The 4D Flow technique effectively captured the 3-dimensional flow pattern of each device. Trifecta exhibited the lowest range of velocity and kinetic energy, maximized EOA (p < 0.0001) and minimized TPGs (p ≤ 0.015) if compared with Magna and Crown, these reporting minor EOA difference s (p ≥ 0.042) and similar TPGs (p ≥ 0.25). 4D Flow TPGs estimations strongly correlated against ground-truth data from pressure transducers; viscous energy dissipation proved to be inversely proportional to the fluid jet penetration.

CONCLUSION

The proposed 4D Flow analysis pinpointed consistent hemodynamic differences among BPVs, highlighting the not negligible effect of device size on the fluidynamic outcomes. The efficacy of non-invasive 4D Flow MRI protocol could shed light on how standardize the comparison among devices in relation to their actual hemodynamic performances and improve current criteria for their selection.

Multimodality Imaging of Complications of Cardiac Valve Surgeries

Replacement with a prosthetic heart valve (PHV) remains the definitive surgical procedure for management of severe cardiac valve disease. PHV dysfunction is uncommon but can be a life-threatening condition. The broad hemodynamic and pathophysiologic manifestations of PHV dysfunction are stenosis, regurgitation, and a stuck leaflet. Specific structural abnormalities that cause PHV dysfunction include prosthetic valve-patient mismatch, structural failure, valve calcification, dehiscence, paravalvular leak, infective endocarditis, abscess, pseudoaneurysm, abnormal connections, thrombus, hypoattenuating leaflet thickening, and pannus. Multiple imaging modalities are available for evaluating a PHV and its dysfunction. Transthoracic echocardiography is often the first-line imaging modality, with additional modalities such as transesophageal echocardiography, CT, MRI, cine fluoroscopy, and nuclear medicine used for further characterization and establishing a specific cause. The authors review PHVs and the role of imaging modalities in evaluation of PHV dysfunction and illustrate the imaging appearances of different complications. Online supplemental material is available for this article. ^©RSNA, 2019.

Limitations in the Assessment of Prosthesis-Patient Mismatch

Background Prosthesis-patient mismatch (PPM) after aortic valve replacement (AVR) may affect survival but data are conflicting. It is assessed by relating effective orifice area (EOA) to body surface area (EOAi). EOA is patient-specific as the result of flow-velocity times area at the individual patient's outflow tract levels (LVOTA) divided by trans-prosthetic flow velocity. However, some studies use projected EOAs (i.e., valve size associated EOAs from other patient populations) to assess how PPM affects outcome.

Methods We analyzed 76 studies addressing hemodynamic outcome and/or mortality after bioprosthetic AVR.

Results In 48 studies, projected or measured EOA for calculation of EOAi and PPM assessment was used (of which 25 demonstrated an effect on survival). We identified 28 additional studies providing measured EOA values and the corresponding Bernoulli's pressure gradients after AVR. Despite EOA being a patient-specific parameter, 77% of studies assessing a PPM impact on survival used projected EOAs. The 28 studies are providing measured EOA values and the corresponding Bernoulli's pressure gradients in patients after AVR showed a highly significant, linear relationship between EOA and Bernoulli's gradient. Considering this relationship, it is surprising that relating EOA to body surface area (BSA) (EOAi) is standard but relating pressure gradients to BSA is not.

Conclusion We conclude that the majority of studies assessing PPM have used false assumptions because EOA is a patient-specific parameter and cannot be transferred to other patients. In addition, the use of EOAi to assess PPM may not be appropriate and could explain the inconsistent relation between PPM and survival in previous studies.

Hydrodynamic and Geometric Behavior of Two Pericardial Prostheses Implanted in Small Aortic Roots

Hydrodynamic performance of stented bioprostheses is far below that of the native valve. One of the reasons is that the internal diameter of the prosthesis is usually smaller than that of the native valve. However, other valve characteristics are also important in generating the pressure drop. We aimed to assess, in an ex vivo pulsatile mock loop, the hydrodynamic behavior of two bioprostheses, Trifecta and Mitroflow, to ascertain which geometric terms are limiting factors in hydrodynamic performance. At stroke volumes between 30 and 60 ml, Trifecta showed lower pressure drop, energy dissipation and valve resistance, and greater effective orifice area. This trend was overturned at higher stroke volumes, with Mitroflow slightly outperforming Trifecta. The geometric determinants were consistent with these results. Trifecta achieved its maximum opening area already at the lowest stroke volumes, featuring a divergent shape at the systolic peak. Mitroflow showed a complex opening pattern, featuring a convergent shape at the systolic peak for lower stroke volumes, while reaching its maximum opening area at higher stroke volumes, with a divergent shape. The two bioprostheses, although similar in design, displayed different biomechanical behaviors. The internal diameter of each bioprosthesis did not show to be strictly correlated with its hydrodynamic characteristics.

Effect of bioprostheses anti-calcification treatment: comparative follow-up between Mitroflow LX and Magna pericardial xenografts using a propensity score-weighted analysis

Objectives

The efficacy of anti-calcification treatment of bioprosthetic heart valves remains unclear. The aim of this study was to compare the clinical outcomes between Mitroflow LX valve, without anti-calcification treatment, and the Carpentier-Edwards Perimount Magna (P-Magna), with anti-calcification treatment.

Methods

Between 2005 and 2012, 625 consecutive patients underwent aortic valve replacement either with a Mitroflow LX ( n  = 329) or a P-Magna ( n  = 296). Variables regarding patient-related risk factors and operative data were accounted for an inverse probability of treatment weighting analysis. Then, adjusted survival outcomes and the rate of structural valve disease (SVD) were assessed for each group.

Results

Mean follow-up times were 4.1 ± 2.29 years and 3.9 ± 2.63 years, respectively ( P  = 0.34). Adjusted overall survival rate was higher in the P-Magna group than in the Mitroflow LX group at 8 years (69.1% vs 51.9%, respectively) [HR = 1.44, 95% CI: 1.01 to 2.06; P  = 0.0467]. Similarly, the 8-year cardiac-related survival rate was also higher in the P-Magna group [HR = 1.99, 95% CI: 1.19 to 3.32; P  = 0.0083]. One patient (0.8%) with P-Magna and 23 patients (18.5%) with Mitroflow LX group developed SVD (0.24% per patient-year vs 4.5% per patient-year, respectively; P  < 0.001). At 5 and 8 years, valve-related survival rates did not differ significantly between both groups [HR = 1.67, 95% CI: 0.95 to 2.95; P  = 0.075].

Conclusions

The P-Magna prosthesis showed significantly better overall and cardiac-related survival than the Mitroflow LX. The higher early SVD and reoperation rates seen with the Mitroflow LX prosthesis did not impact negatively on valve-related survival.

The TRIBECA study: (TRI)fecta (B)ioprosthesis (E)valuation versus (C)arpentier Magna-Ease in (A)ortic position

OBJECTIVE

To determine whether the Trifecta bioprosthetic aortic valve produces postoperative haemodynamic results comparable with or better than those of the Magna Ease aortic valve bioprosthesis.

METHODS

We retrospectively reviewed the medical records of patients who had undergone aortic valve replacement with Trifecta or Magna Ease prostheses at eight European institutions between January 2011 and May 2013, and analysed early postoperative haemodynamic performance by means of echocardiography.

RESULTS

A total of 791 patients underwent aortic valve replacement (469 Magna Ease, 322 Trifecta). Haemodynamic variables were evaluated on discharge and during the follow-up (minimum 6 months, maximum 12 months). The mean gradient and the indexed effective orifice area (IEOA) were as follows: 10 mmHg [interquartile range (IQR): 8-13] and 1.10 cm(2)/m(2) (IQR: 0.95-1.27) for Trifecta; 16 mmHg (IQR: 11-22) and 0.96 cm(2)/m(2) (IQR: 0.77-1.13) for Magna Ease (P < 0.001). These significant differences were maintained across all valve sizes. Similar statistically significant differences were found when patients were matched and/or stratified for preoperative characteristics: body-surface area, ejection fraction, mean gradients and valve size. Severe prosthesis-patient mismatch (IEOA: <0.65 cm(2)/m(2)) was detected in 2 patients (0.6%) with Trifecta and 40 patients (8.5%) with Magna Ease (P < 0.001).

CONCLUSIONS

The haemodynamic performance of the Trifecta bioprosthesis was superior to that of the Magna Ease valve across all conventional prosthesis sizes, with almost no incidence of severe patient-prosthesis mismatch. The long-term follow-up is needed to determine whether these significant haemodynamic differences will persist, and influence clinical outcomes.

Comparison of the early haemodynamics of stented pericardial and porcine aortic valves

Data comparing the haemodynamic performance of stented pericardial and porcine aortic valves are conflicting. Hence, we performed a systematic review and meta-analysis comparing the early haemodynamic parameters of stented pericardial and porcine valves in patients undergoing isolated aortic valve replacement. Medline, EMBASE and Web of Science were queried for English language original publications from 2000 to 2013. Studies comparing porcine (PoV) and pericardial (PeV) with regard to their haemodynamic parameters were included in this review. Continuous data were pooled using the mean difference (MD) or the standardized mean difference (SMD). A random-effect inverse weighted analysis was conducted; a P-value<0.05 is considered statistically significant. Results are presented with 95% confidence intervals. Thirteen studies (1265 PeV patients and 871 PoV patients) were included in this analysis. The pooled transvalvular mean gradient was lower for PeV [MD -4.6 (-6.45 to -2.77) mmHg; P<0.01]. Limiting this analysis to small valves (19 and 21 mm; eight studies; 714 patients) revealed that the PeV gradients were significantly lower [MD -4.5 (-5.7 to -3.2); P=0.001]. The corresponding effective orifice area of PeV was significantly larger than PoV [SMD 0.42 (0.15-0.69); P<0.01]. A sensitivity analysis comprising only randomized controlled trials did not significantly alter results. When compared with porcine valves, stented pericardial aortic valves have lower mean transvalvular gradients early after implant. Even pericardial valves in smaller sizes (19 and 21 mm) have a better haemodynamic profile when compared with their counterparts.

Rigorous patient-prosthesis matching of Perimount Magna aortic bioprosthesis

Background

Severe patient-prosthesis mismatch, defined as effective orifice area index ≤0.65 cm2 m−2, has demonstrated poor long-term survival after aortic valve replacement. Reported rates of severe mismatch involving the Perimount Magna aortic bioprosthesis range from 4% to 20% in patients with a small annulus.

Methods

Between June 2008 and August 2011, 251 patients (mean age 70.5 ± 10.2 years; mean body surface area 1.55 ± 0.19 m2) underwent aortic valve replacement with a Perimount Magna bioprosthesis, with or without concomitant procedures. We performed our procedure with rigorous patient-prosthesis matching to implant a valve appropriately sized to each patient, and carried out annular enlargement when a 19-mm valve did not fit. The bioprosthetic performance was evaluated by transthoracic echocardiography predischarge and at 1 and 2 years after surgery.

Results

Overall hospital mortality was 1.6%. Only 5 (2.0%) patients required annular enlargement. The mean follow-up period was 19.1 ± 10.7 months with a 98.4% completion rate. Predischarge data showed a mean effective orifice area index of 1.21 ± 0.20 cm2 m−2. Moderate mismatch, defined as effective orifice area index ≤0.85 cm2 m−2, developed in 4 (1.6%) patients. None developed severe mismatch. Data at 1 and 2 years showed only two cases of moderate mismatch; neither was severe.

Conclusions

Rigorous patient-prosthesis matching maximized the performance of the Perimount Magna, and no severe mismatch resulted in this Japanese population of aortic valve replacement patients.

Tissue engineering of autologous heart valves: a focused update

The prevalence of valvular heart disease is expected to increase in the coming decades, with an associated rise in valve-related surgeries. Current options for valve prostheses remain limited, essentially confined to mechanical or biological valves. Neither selection provides an optimal balance between structural integrity and associated morbidity. Mechanical valves offer exceptional durability coupled with a considerable risk of thrombogenesis. Conversely, a biological prosthesis affords freedom from anticoagulation, but with a truncated valve lifespan. Tissue-engineered heart valves have been touted as a solution to this dilemma, by offering an immunopriviledged prosthesis combined with resistance from degeneration and the potential to grow. Although the reality of commercially available tissue-engineered heart valves remains distant, this article will highlight the cellular and clinical advancements in recent years.

Comparison between three types of stented pericardial aortic valves (Trivalve trial): study protocol for a randomized controlled trial

Background

Aortic valve stenosis is one of the most common heart diseases in older patients. Nowadays, surgical aortic valve replacement is the ‘gold standard’ treatment for this pathology and the most implanted prostheses are biological ones. The three most implanted bovine bioprostheses are the Trifecta valve (St. Jude Medical, Minneapolis, MN, USA), the Mitroflow valve (Sorin Group, Saluggia, Italy), and the Carpentier-Edwards Magna Ease valve (Edwards Lifesciences, Irvine, CA, USA). We propose a randomized trial to objectively assess the hemodynamic performances of these bioprostheses.

Methods and design

First, we will measure the aortic annulus diameter using CT-scan, echocardiography and by direct sizing in the operating room after native aortic valve resection. The accuracy of information, in terms of size and spatial dimensions of each bioprosthesis provided by manufacturers, will be checked. Their hemodynamic performances will be assessed postoperatively at the seventh day and the sixth month after surgery.

Discussion

This prospective controlled randomized trial aims to verify and compare the hemodynamic performances and the sizing of these three bioprostheses. The data obtained may help surgeons to choose the best suitable bioprosthesis according to each patient’s morphological characteristics.

Trial registration

ClinicalTrials.gov Identifier: NCT01522352