Impact of Prosthesis-Patient Mismatch on Cardiac Events and Midterm Mortality After Aortic Valve Replacement in Patients With Pure Aortic Stenosis

Impact of Prosthesis-Patient Mismatch After Surgical Aortic Valve Replacement: Systematic Review and Meta-Analysis of Reconstructed Time-to-Event Data of 122 989 Patients With 592 952 Patient-Years

BACKGROUND

It remains controversial whether prosthesis-patient mismatch (PPM) impacts long-term outcomes after surgical aortic valve replacement. We aimed to evaluate the association of PPM with mortality, rehospitalizations, and aortic valve reinterventions.

METHODS AND RESULTS

We performed a systematic review with meta-analysis of reconstructed time-to-event data of studies published by March 2023 (according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses). Sixty-five studies met our eligibility criteria and included 122 989 patients (any PPM: 68 332 patients, 55.6%). At 25 years of follow-up, the survival rates were 11.8% and 20.6% in patients with and without any PPM, respectively (hazard ratio [HR], 1.16 [95% CI, 1.13-1.18], P<0.001). At 20 years of follow-up, the survival rates were 19.5%, 12.1%, and 8.8% in patients with no, moderate, and severe PPM, respectively (moderate versus no PPM: HR, 1.09 [95% CI, 1.06-1.11], P<0.001; severe versus no PPM: HR, 1.29 [95% CI, 1.24-1.35], P<0.001). PPM was associated with higher risk of cardiac death, heart failure-related hospitalizations, and aortic valve reinterventions over time (P<0.001). Statistically significant associations between PPM and worse survival were observed regardless of valve type (bioprosthetic versus mechanical valves), contemporary PPM definitions unadjusted and adjusted for body mass index, and PPM quantification method (in vitro, in vivo, Doppler echocardiography). Our meta-regression analysis revealed that populations with more women tend to have higher HRs for all-cause death associated with PPM.

CONCLUSIONS

The results of the present study suggest that any degree of PPM is associated with poorer long-term outcomes following surgical aortic valve replacement and provide support for implementation of preventive strategies to avoid PPM after surgical aortic valve replacement.

Figure of eight suture technique in aortic valve replacement decreases prosthesis-patient mismatch

BACKGROUND

While the pledget suture technique has been the standard for surgical aortic. valve replacement (AVR), discussion continues regarding the possibility of the nonpledget suture technique to produce superior structural and hemodynamic parameters. This study aims to assess the effectiveness of the figure-of-eight suture technique in AVR, as determined by the incidence of prosthesis-patient mismatch (PPM).

METHODS

We reviewed records of patients (N = 629) who underwent a surgical AVR procedure between January 2011 and July 2018 at a single institution. Indexed effective orifice area values and PPM incidence were calculated from implanted valve size and patient body surface area. Incidence of none, moderate, and severe PPM was compared across AVR suture techniques.

RESULTS

A total of 570 pledget and 59 figure-of-eight patients were compared for incidence of PPM. Patients who received AVR with the pledget suture technique had significantly lower echocardiographic measurements of baseline ejection fraction than patients who had received AVR with the figure-of-eight suture technique (p = 0.003). Patients who received the figure-of eight suture had a 14% decrease in moderate PPM compared to patients who received the pledget suture (p = 0.022). Patients who received the figure-of-eight suture also had a significantly higher rate of no PPM (p = 0.044).

CONCLUSIONS

The use of the figure-of-eight suture technique in AVR can reduce the incidence of moderate PPM. While the pledget suture is the standard technique in AVR, the figure-of-eight suture technique may offer better structural and hemodynamic outcomes, especially for patients with a smaller aortic annulus.

Biological Scaffolds for Congenital Heart Disease

Congenital heart disease (CHD) is the most predominant birth defect and can require several invasive surgeries throughout childhood. The absence of materials with growth and remodelling potential is a limitation of currently used prosthetics in cardiovascular surgery, as well as their susceptibility to calcification. The field of tissue engineering has emerged as a regenerative medicine approach aiming to develop durable scaffolds possessing the ability to grow and remodel upon implantation into the defective hearts of babies and children with CHD. Though tissue engineering has produced several synthetic scaffolds, most of them failed to be successfully translated in this life-endangering clinical scenario, and currently, biological scaffolds are the most extensively used. This review aims to thoroughly summarise the existing biological scaffolds for the treatment of paediatric CHD, categorised as homografts and xenografts, and present the preclinical and clinical studies. Fixation as well as techniques of decellularisation will be reported, highlighting the importance of these approaches for the successful implantation of biological scaffolds that avoid prosthetic rejection. Additionally, cardiac scaffolds for paediatric CHD can be implanted as acellular prostheses, or recellularised before implantation, and cellularisation techniques will be extensively discussed.

Extent of Left Ventricular Mass Regression and Impact of Global Left Ventricular Afterload on Cardiac Events and Mortality after Aortic Valve Replacement

Patient-prosthesis mismatch (PPM) causes a high transvalvular pressure gradient and residual left ventricular (LV) hypertrophy, consequently influencing long-term results. This study aimed to find the relationships between hemodynamic parameters and LV mass regression and determine the risk predictors of major adverse cardiovascular and cerebral events (MACCE) after aortic valve replacement (AVR) for aortic stenosis. Methods and Results: Preoperative and postoperative Doppler echocardiography data were evaluated for 120 patients after AVR. The patients' mean age was 67.7 years; 55% of the patients were male. Forty-four (37%) patients suffered from MACCE during a mean follow-up period of 3.6 ± 2 years. The following hemodynamic parameters at follow-up were associated with lower relative indexed LV mass (LVMI) regression: lower postoperative indexed effective orifice area, greater mean transvalvular pressure gradient (MPG), greater stroke work loss (SWL), and concentric or eccentric LV remodeling mode. The following hemodynamic parameters at follow-up were associated with a higher risk of MACCE: higher valvuloarterial impedance (Z_VA), greater SWL, greater MPG, greater relative wall thickness, greater LVMI, and hypertrophic LV remodeling mode. Lower relative LVMI regression was associated with a higher risk of MACCE (hazard ratio, 1.01: 95% confidence interval, 1.003-1.03). The corresponding cutoff of relative LVMI regression was -14%. Conclusions: Changes in hemodynamic parameters were independently associated with relative LVMI regression. Impaired reverse remodeling and persistent residual LV hypertrophy were independent risk predictors of MACCE. An LVMI regression lower than 14% indicated higher MACCE. A postoperative Z_VA greater than 3.5 mmHg/mL/m² was an independent risk predictor of cardiac events and mortality after AVR. Preventive strategies should be used at the time of the operation to avoid PPM.

Prosthesis-Patient Mismatch in Small Aortic Annuli: Self-Expandable vs. Balloon-Expandable Transcatheter Aortic Valve Replacement

Prosthesis−patient mismatch (PPM) is associated with worse outcomes following surgical aortic valve replacement (SAVR). PPM has been identified in a significant proportion of TAVR, particularly in patients with small aortic annuli. Our objective was to evaluate the hemodynamic performances of balloon-expandable (BE) (Sapiens 3TM) versus two different self-expandable (SE) (Evolut ProTM, Accurate NeoTM) TAVR devices in patients with small aortic annulus defined by a computed tomography aortic annulus area (AAA) between 330 and 440 mm2. We enrolled 131 consecutive patients corresponding to 76 Sapiens 3 23 mm (58.0%), 26 Evolut Pro (19.9%) and 29 Accurate Neo (22.1%). Mean age was 82.5 ± 7.06 years, 22.9% of patients were male and mean Euroscore was 4.0%. Mean AAA was 374 ± 27 mm2 for Sapiens 3, 383 ± 29 mm2 for Corevalve Evolut Pro and 389 ± 25 mm2 for Accurate Neo. BE devices were associated with significantly higher rates of PPM (39.5%) as compared to SE devices (15.4% for Corevalve Evolut Pro and 6.9% for Accurate Neo) (p < 0.0001). Paravalvular leaks ≥ 2/4 were more often observed in SE devices (15.4% for Corevalve Evolut Pro and 17.2% for Accurate Neo) than in BE devices (2.6%) (p = 0.007). In conclusion, SE TAVR devices did achieve better hemodynamic results despite higher rates of paravalvular leaks. Therefore, SE TAVI devices could be considered as first choice in small aortic anatomy.

Patient-Prosthesis Mismatch in Contemporary Small-Size Mechanical Prostheses Does Not Impact Survival at 10 Years

BACKGROUND

The effect of PPM in mechanical prostheses on long-term survival is not well-established.

METHODS

Patients who received a 21 mm or smaller aortic valve between 2000 and 2011 were retrospectively analyzed (n = 416). Propensity matching was used in order to account for baseline differences in patient subgroups (PPM vs. no PPM; severe PPM vs. no severe PPM).

RESULTS

Five- and ten-year survival was 78 ± 3.52% and 64.51 ± 4.51% in patients with PPM, versus 83.3 ± 3.12% and 69.37 ± 4.36% in patients without (p = 0.28) when analyzed at 10.39 ± 5.25 years after the primary procedure. Independent risk factors for impaired survival, after matching, were age, serum creatinine, and severe pulmonary hypertension. Five- and ten-year survival in patients with severe PPM was 73.34 ± 6.01% and 61.76 ± 8.17%, respectively, versus 74.72 ± 5.68% and 67.50 ± 7.09% in those without (p = 0.49), at 8.82 ± 5.17 years after SAVR. Age was the only independent variable that influenced long-term survival when severe PPM was added to the model.

CONCLUSIONS

PPM or severe PPM does not impact long-term survival up to 10 years in mechanical valve recipients when matching for preoperative variables.

Racial Differences in the Incidence and Impact of Prosthesis-Patient Mismatch After Transcatheter Aortic Valve Replacement

OBJECTIVES

The aim of this study was to compare the incidence and prognostic significance of prosthesis-patient mismatch (PPM) after transcatheter aortic valve replacement (TAVR) according to racial groups.

BACKGROUND

PPM after TAVR may be of more concern in Asian populations considering their relatively small annular and valve sizes compared with Western populations.

METHODS

TP-TAVR (Transpacific TAVR Registry) was an international multicenter cohort study of patients with severe aortic stenosis who underwent TAVR in the United States and South Korea from January 2015 to November 2019. PPM was defined as moderate (0.65-0.85 cm²/m²) or severe (<0.65 cm²/m²) at the indexed effective orifice area. The primary outcome was a composite of death, stroke, or rehospitalization at 1 year.

RESULTS

Among 1,101 eligible patients (533 Asian and 569 non-Asian), the incidence of PPM was significantly lower in the Asian population (33.6%; moderate, 26.5%; severe, 7.1%) than in the non-Asian population (54.5%; moderate, 29.8%; severe, 24.7%). The 1-year rate of the primary outcome was similar between the PPM and non-PPM groups (27.5% vs 28.1%; P = 0.69); this pattern was consistent between Asian (25.4% vs 25.2%; P = 0.31) and non-Asian (28.7% vs 32.1%; P = 0.97) patients. After multivariable adjustment, the risk for the primary outcome did not significantly differ between the PPM and non-PPM groups in the overall population (HR: 0.95; 95% CI: 0.74-1.21), in Asian patients (HR: 1.07; 95% CI: 0.74-1.55), and in non-Asian patients (HR: 0.86; 95% CI: 0.63-1.19).

CONCLUSIONS

In this study of patients with severe aortic stenosis who underwent TAVR, the incidence of PPM was significantly lower in Asian patients than in non-Asian patients. The 1-year risk for the primary composite outcome was similar between the PPM and non-PPM groups regardless of racial group. (Transpacific TAVR Registry [TP-TAVR]; NCT03826264).

Choosing Between Transcatheter Aortic Valve Replacement and Surgery in the Low-Risk Transcatheter Aortic Valve Replacement Era

The landmark results of the low surgical risk pivotal transcatheter aortic valve replacement (TAVR) trials fueled speculation that the role of surgical aortic valve replacement (SAVR) would be limited in the future. Instead, the field has pivoted away from reductive surgical risk stratification toward understanding the complex interplay of anatomy, timing, and surgical risk to optimize the lifetime management of aortic stenosis. In this review, we systematically explore the subtleties that influence the choice between TAVR and surgery in the low-risk TAVR era.

Aortic valve neocuspidization with autologous pericardium in adult patients: UK experience and meta-analytic comparison with other aortic valve substitutes

OBJECTIVES

We sought to provide further evidence on the safety and efficacy of aortic valve neocuspidization (AVNeo) using autologous pericardium in adult patients with aortic valve disease by reporting clinical and echocardiographic results from the first UK experience and performing a meta-analytic comparison with other biological valve substitutes.

METHODS

We reported clinical and echocardiographic outcomes of 55 patients (mean age 58 ± 15 years) undergoing AVNeo with autologous pericardium in 2 UK centres from 2018 to 2020. These results were included in a meta-analytic comparison between series on AVNeo (7 studies, 1205 patients, mean weighted follow-up 3.6 years) versus Trifecta (10 studies, 8705 patients, 3.8 years), Magna Ease (3 studies, 3137 patients, 4.1 years), Freedom Solo (4 studies, 1869 patients, 4.4 years), Freestyle (4 studies, 4307 patients, 7 years), Mitroflow (4 studies, 4760 patients, 4.1 years) and autograft aortic valve (7 papers, 3839 patients, 9.1 years).

RESULTS

In the present series no patients required intraoperative conversion. After mean follow-up of 12.5 ± 0.9 months, 3 patients presented with endocarditis and 1 required reintervention. The remaining patients had absent or mild aortic valve insufficiency with very low peak and mean transvalvular gradients (16 ± 3.7 and 9 ± 2.2 mmHg, respectively). Meta-analytic estimates showed non-significant difference between AVNeo and all but Magna Ease valves with regards to structural valve degeneration, reintervention and endocarditis. When compared Magna Ease valve, AVNeo and other valve substitutes showed an excess of valve-related events.

CONCLUSIONS

AVNeo is safe, associated with excellent haemodynamic profile. Its midterm risk of valve-related events is comparable to most biological valve substitutes. Magna Ease is potentially the best biological choice as far as risk of reintervention is concerned.

The relation of structural valve deterioration to adverse remodelling and outcome in patients with biological heart valve prostheses

AIMS

Native valve aortic stenosis is associated with adverse remodelling of the left ventricle and remodelling is stopped or even reversed with aortic valve replacement (AVR). However, the degeneration of bioprostheses and development of structural valve deterioration (SVD) may affect this.

METHODS AND RESULTS

To assess the association with SVD, remodelling and outcome 451 patients from a single surgical centre who had undergone AVR with a Mitroflow pericardial bioprosthesis were studied. All patients were assessed in 2014 and a subgroup of patients (N = 327) were re-exanimated again after at least 18 months [median time of 27 (interquartile range, IQR 26-33) months] including echocardiography, measurements of N-terminal pro-brain natriuretic peptide, and assessment of functional status. SVD was based on echocardiography. Moderate SVD was present in 63 patients (14%) and severe SVD in 19 (4%), in the subgroup with follow-up echocardiography 48 patients (15%) patients had moderate to severe SVD at first examination. Patients with SVD had significantly greater increase in left ventricular (LV) mass index [21.6 g/m2 (IQR 5.7-48.3 g/m2) vs. 9.1 g/m2 (-8.6 to 27.3 g/m2), P = 0.01]. Further, patients with SVD had lower LV ejection fraction [55% (IQR 51-62%) vs. 60% (IQR 54-63%), P = 0.01] at follow-up. During follow-up, 94 patients (21%) met the composite endpoint of death or reoperation due to SVD and 41 patient readmitted for heart failure. In multivariable Cox regression analysis, severe SVD [hazard ratio (HR) 2.64 (1.37-5.07), P = 0.004] was associated with composite endpoint, and readmission for heart failure [HR 3.82 (1.53-9.51), P = 0.004].

CONCLUSION

SVD in aortic bioprostheses is associated with adverse LV remodelling and adverse outcome.

Clinical and Technical Challenges of Prosthesis-Patient Mismatch After Transcatheter Aortic Valve Implantation

Prosthesis-patient mismatch (PPM) is present when the effective area of a prosthetic valve inserted into a patient is inferior to that of a normal human valve; the hemodynamic consequence of a valve too small compared with the size of the patient's body is the generation of higher than expected transprosthetic gradients. Despite evidence of increased risk of short- and long-term mortality and of structural valve degeneration in patients with PPM after surgical aortic valve replacement, its clinical impact in patients subject to transcatheter aortic valve implantation (TAVI) is yet unclear. We aim to review and update on the definition and incidence of PPM after TAVI, and its prognostic implications in the overall population and in higher-risk subgroups, such as small aortic annuli or valve-in-valve procedures. Last, we will focus on the armamentarium available in order to reduce risk of PPM when planning a TAVI procedure.

Predictors and Clinical Impact of Prosthesis-Patient Mismatch After Self-Expandable TAVR in Small Annuli

OBJECTIVES

The aim of this study was to define predictors of prosthesis-patient mismatch (PPM) and its impact on mortality after transcatheter aortic valve replacement (TAVR) with self-expandable valves (SEVs) in patients with small annuli.

BACKGROUND

TAVR seems to reduce the risk for PPM compared with surgical aortic valve replacement, especially in patients with small aortic annuli. Nevertheless, predictors and impact of PPM in this population have not been clarified yet.

METHODS

Predictors of PPM and all-cause mortality were investigated using multivariable logistic regression analysis from the cohort of the TAVI-SMALL (International Multicenter Registry to Evaluate the Performance of Self-Expandable Valves in Small Aortic Annuli) registry, which included patients with severe aortic stenosis and small annuli (annular perimeter <72 mm or area <400 mm² on computed tomography) treated with transcatheter SEVs: 445 patients with (n = 129) and without (n = 316) PPM were enrolled.

RESULTS

Intra-annular valves conferred increased risk for PPM (odds ratio [OR]: 2.36; 95% confidence interval [CI]: 1.16 to 4.81), while post-dilation (OR: 0.46; 95% CI: 0.25-0.84) and valve oversizing (OR: 0.53; 95% CI: 0.28-1.00) seemed to protect against PPM occurrence. At a median follow-up of 354 days, patients with severe PPM, but not those with moderate PPM, had a higher all-cause mortality rate compared with those without PPM (log-rank p = 0.008). Multivariable Cox regression confirmed severe PPM as an independent predictor of all-cause mortality (hazard ratio: 4.27; 95% CI: 1.34 to 13.6).

CONCLUSIONS

Among patients with aortic stenosis and small aortic annuli undergoing transcatheter SEV implantation, use of intra-annular valves yielded higher risk for PPM; conversely, post-dilation and valve oversizing protected against PPM occurrence. Severe PPM was independently associated with all-cause mortality.

Transcatheter Aortic Valve Implantation for Failed Surgical Aortic Bioprostheses Using a Self-Expanding Device (from the Prospective VIVA Post Market Study)

Patients with symptomatic aortic stenosis are often treated with a surgical valve replacement. Surgical bioprosthetic valves degenerate over time and therefore may necessitate a redo surgery. This analysis reports the 2-year clinical outcomes of the Valve-in-Valve study, which evaluated transcatheter aortic valve implantation using the CoreValve and Evolut R devices in patients with degenerated surgical aortic bioprostheses at high risk for surgery. The prospective Valve-in-Valve study enrolled 202 eligible patients with failing surgical aortic bioprostheses due to stenosis, regurgitation, or a combination of both. The Evolut R bioprosthesis was used in 90.5% of valve-in-valve transcatheter aortic valve implantation cases. Two-year all-cause and cardiovascular mortality rates were 16.5% and 11.1%, respectively. Other clinical events included stroke (7.9%), disabling stroke (1.7%), and new pacemaker implantation (10.1%). The 2-year all-cause mortality rate was significantly higher in patients with discharge mean gradients ≥20 mmHg vs. those with lower mean gradients (21.0% vs 7.6%, p = 0.025). Discharge mean gradients ≥20 mm Hg were associated with smaller surgical bioprostheses (OR, 7.2 [95% CI 2.3 to 22.1]. In patients with failing surgical aortic bioprostheses, valve-in-valve treatment using a supra-annular self-expanding bioprosthesis provides significant functional improvements with acceptable rates of complications, especially if a postprocedural mean gradient of <20 mmHg can be achieved.

Prosthesis-patient mismatch after surgical aortic valve replacement in patients with aortic stenosis

OBJECTIVES

The issue of prosthesis-patient mismatch (PPM) after surgical aortic valve replacement (SAVR) has been a controversial topic. We sought to evaluate the long-term clinical impacts of PPM in patients undergoing SAVR in an updated, homogeneous cohort.

METHODS

Using the prospective institutional database, we identified 895 adult patients (median age 66, interquartile range 58-72; 45.6% women) who underwent isolated SAVR from January 2000 to March 2016. Those with pure aortic insufficiency and concomitant other cardiac operations were excluded from this study cohort. The presence of a significant PPM was defined as an indexed effective orifice area 0.85 cm2/m2 or less. The outcome of interest was all-cause deaths. Propensity score matching was performed for adjusting bias.

RESULTS

Significant PPM was present in 247 patients (27.6%). During the follow-up period (mean 71.2 ± 51.04 months), 134 patients (15%) died. Survival rates at 10 and 15 years were 78.3% vs 83.8% and 71.3% vs 57.6% in the PPM and non-PPM groups (P = 0.972). Risk factor analysis indicated that developing PPM was not associated with a risk of death. After propensity score matching (1:1), developing PPM was not a risk factor for long-term death as well (P = 0.584).

CONCLUSIONS

Significant PPM was common after SAVR in patients with aortic stenosis. However, there was no significant difference in survival rate between those with and without PPM.

Aortic root widening: “pro et contra”

In patients with a small aortic annulus, the clinical benefits of aortic valve replacement depend on avoidance of patient-prosthesis mismatch as it is associated with reduced overall survival. Aortic root widening or enlargement is a useful technique to implant larger valve prosthesis to prevent patient-prosthesis mismatch. Posterior annular enlargement is the commonest technique used for aortic root enlargement. Consistent enlargement of the aortic root requires more extensive procedures like Manouguian or Konno-Rastan techniques. The patients commonly selected are younger patients with good life expectancy. However, caution is advised in applying this procedure in elderly patients, patients with heavily calcified annulus and when performing concomitant procedures. There is no definitive conclusion on the best material to use for the reconstruction of aortic annulus and aorta in aortic root enlargement procedures.

Aortic Annular Enlargement in the Elderly: Short and Long-Term Outcomes in the United States

BACKGROUND

Patient prosthesis mismatch is associated with significant long-term morbidity and mortality after aortic valve replacement, but the role and outcomes of annular enlargement (AE) remain poorly defined. We hypothesized that increasing rates of AE may lead to improved outcomes for patients at risk for severe patient prosthesis mismatch.

METHODS

Patients over age 65 years undergoing surgical aortic valve replacement with or without coronary artery bypass grafting from 2008-2016 in The Society of Thoracic Surgeons Adult Cardiac Surgery Database with matching Centers for Medicare & Medicaid Services data were included (n=189,268). Univariate, multivariate, and time-to-event analysis was used to evaluate the association between AE and early and late outcomes. Patients were stratified by projected degree of patient prosthesis mismatch based on calculated effective orifice area index.

RESULTS

A total of 5412 (2.9%) patients underwent AE. The Society of Thoracic Surgeons Adult Cardiac Surgery Database-predicted mortality was similar between AE and non-AE groups (2.97% vs 2.99%, P = .052). Patients undergoing AE had higher risk-adjusted rates of 30-day complications and death (5.4% vs 3.4%, P < .0001), but no differences in long-term rates of stroke, heart failure re-hospitalization,s or aortic valve reoperation. Survival analysis demonstrated a higher risk of mortality with AE during the first 3 years, after which the survival curves cross, favoring AE.

CONCLUSIONS

These data suggest that annular enlargement during surgical aortic valve replacement is associated with increased short-term risk in a Medicare population. Survival curves crossed after 3 years, which may portend a benefit in select patients. However, annular enlargement is still only performed in the minority of patients who are at risk for patient prosthesis mismatch.

Hemodynamic Performance of Pericardial Bioprostheses in the Aortic Position

Background

This study was conducted to evaluate the hemodynamic performance and the incidence of prosthesis-patient mismatch (PPM) after aortic valve replacement (AVR) using bovine pericardial valves (Carpentier-Edwards Perimount Magana and Magna Ease).

Methods

In total, 216 patients (mean age, 70.0±10.5 years) who underwent AVR using stented bovine pericardial valves and had follow-up echocardiography between 3 months and 2 years (mean, 12.0±6.6 months) after surgery were enrolled. The implanted valve sizes were 19, 21, 23, and 25 mm in 32, 56, 99, and 29 patients, respectively.

Results

On follow-up echocardiography, the mean transvalvular pressure gradients for the 19-mm, 21-mm, 23-mm, and 25-mm valves were 13.3±4.4, 12.6±4.2, 10.5±3.9, and 10.2± 3.7 mm Hg, respectively. The effective orifice area (EOA) was 1.25±0.26, 1.54±0.31, 1.81±0.41, and 1.87±0.33 cm², respectively. These values were smaller than those suggested by the manufacturer for the corresponding sizes. No patients had PPM, when based on the reference EOA. However, moderate (EOA index ≤0.85 cm²/m²) and severe (EOA index ≤0.65 cm²/m²) PPM was present in 56 patients (11.8%) and 9 patients (1.9%), respectively, when using the measured values.

Conclusion

Carpentier-Edwards Perimount Magna and Magna Ease bovine pericardial valves showed satisfactory hemodynamic performance with low rates of PPM, although the reference EOA could overestimate the true EOA for individual patients.

Prosthesis-Patient Mismatch Increases Early and Late Mortality in Low Risk Aortic Valve Replacement

The concept of prosthesis-patient mismatch (PPM) has gained much attention since first described 40 years ago. Previous studies have shown conflicting evidence regarding increased early and late morbidity and mortality with PPM after aortic valve replacement (AVR). The aim of this study was to evaluate the effects of PPM on short- and long-term mortality in low-risk patients after isolated AVR. A retrospective, single-center study involving 1707 consecutive patients ≤80 years of age with preserved left ventricular systolic function who underwent elective, primary isolated AVR operations from 2008 to 2018. Patients were stratified into 2 groups according to the presence of PPM (n = 96), defined as effective orifice area index <0.85 cm²/m² body surface area, and no-PPM (n = 1611). The effect of PPM on mortality was evaluated with univariate and multivariate analyses. 30-day mortality was 0.8% (4.2% in PPM group vs 0.6 in no-PPM group; P = 0.005). PPM occurred more in female gender, obese and older patients. PPM was highly associated with long-term all-cause mortality (median 4 years [Q1-Q3 2-7]; HR: 1.79, 95% CI: 1.27-2.55, P = 0.002), and remained strongly and independently associated after adjustment for other risk factors (HR: 1.60, 95% CI: 1.10-2.34, P = 0.014). In propensity score-matched analysis, the adjusted mortality risk was higher in PPM group (HR: 2.03, 95% CI: 1.22-3.39, P = 0.006) compared to no-PPM group. In a single-centre observational study, PPM increased early mortality and was independently associated with long-term all-cause mortality after low-risk, primary isolated AVR operations. Strategies to avoid PPM should be explored and implemented.

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.

Men are from mars, women are from venus: Factors responsible for gender differences in outcomes after surgical and trans-catheter aortic valve replacement

Females suffer higher operative (30-day) mortality than males after surgical aortic valve replacement (SAVR). In contrast, outcomes after trans-catheter aortic valve replacement (TAVR) seem to favor females, both in terms of procedural mortality, and more prominently, medium to long-term survival. With an ever-greater number of TAVR procedures being performed, an understanding of factors responsible for gender differences in outcomes after the two AVR modalities is critical for better patient selection. Current evidence suggests that this gender difference in outcomes after SAVR and TAVR stems from differences in baseline risk profiles, as well as inherent anatomic/physiological differences between genders. This review attempts to examine these clinical and physiological factors, with a goal of guiding better patient selection for each AVR modality, and to highlight areas that beg further investigation.

Bioprosthetic Valve Fracture for Valve-in-Valve Transcatheter Aortic Valve Replacement: Rationale, Patient Selection, Technique, and Outcomes

Patient-prosthesis mismatch (PPM) is common after surgical valve aortic replacement. A significant percentage of patients with a small annulus have moderate to severe PPM. The outcomes for patients with larger effective orifice areas and lower gradients are better than for patients with PPM. With the advent of valve-in-valve TAVR, a degenerated surgical bioprosthesis can be treated with a percutaneous approach. However, the issue of PPM cannot be overcome by simply implanting a new valve. The technique of bioprosthetic valve fracture was therefore developed. This allows for implantation of a fully expanded transcatheter valve and results in a large effective orifice.

Clinical outcome and hemodynamic performance of St. Jude Trifecta aortic prosthesis: short-term follow-up and risk factors analysis

BACKGROUND

We retrospectively analysed the short-term outcome of the third-generation St. Jude Trifecta aortic prosthesis.

METHODS

Between December 2014 and December 2017, 177 patients (mean age 75.1±6.8 years, 95 males, 82 females) underwent aortic valve replacement with a St. Jude Trifecta aortic prosthesis and were followed up to 27±9 months. Preoperatively 92 patients (52.0%) were in NYHA class III-IV, EuroSCORE II was 3.2%±2.1%.

RESULTS

Trifecta sizes implanted were 19 mm (n=46) (26%), 21 mm (n=69) (39%), 23 mm (n=46) (26%), 25 mm (n=16) (9%). Concomitant coronary artery bypass grafting was performed in 60 patients (34.0%). Operative mortality was 3.4% (1.7% for isolated aortic valve replacement versus 6.7% for combined aortic valve replacement and coronary artery bypass grafting) (P=0.084). The only independent predictor of mortality was the need for the mechanical ventilation greater than 24 hours (P=0.037); recently occurring myocardial infarction was risk factor for mortality at the univariate analysis only (P=0.013). Three-year survival was 84%±6%, freedom from cardiac death 98%±1%, freedom from prosthetic endocarditis 97%±1%. No thromboembolisms or structural valve degeneration were observed. Patient-prosthesis mismatch (PPM) was absent in 126 patients (71.2%), mild-to-moderate in 32 (18.1%), moderate in 19 (10.7%), severe in no any patient. Follow-up echocardiography showed an average mean and peak trans-aortic valve gradients reduction more than 70% in comparison with preoperative value (P<0.0001), and a significant regression of left ventricular hypertrophy (P<0.0001). Moderate PPM did not negatively affect survival. Concomitant severe coronary artery disease was found as an independent predictor of reduced survival (72%±12% versus 86%±6%) (P=0.015).

CONCLUSIONS

Trifecta aortic prosthesis seems to provide very favourable clinical outcome and hemodynamic performance. At three years, survival was negatively affected by severe coronary artery disease detected at the time of operation. During short-term follow-up, no early structural valve degeneration was been observed. Due to low incidence of PPM and low peak and mean trans-prosthetic aortic valve gradients, third generation Trifecta aortic prosthesis should be considered as one of the best options in the setting of the aortic valve replacement surgery. However, a long-term follow-up is mandatory to confirm the early promising data.

Structural valve deterioration in the Mitroflow biological heart valve prosthesis

OBJECTIVES

Concern has been raised regarding the long-term durability of the Mitroflow biological heart valve prosthesis. Our aim was to assess the incidence of structural valve degeneration (SVD) for the Mitroflow bioprosthesis in a nationwide study in Denmark including all patients alive in Denmark who had received a Mitroflow aortic bioprosthesis since 2000.

METHODS

Patients alive in Denmark with a Mitroflow bioprosthesis implanted since January 2000 were invited to participate in a nationwide cross-sectional study with a predefined definition of SVD. Of 1552 patients, 861 patients had died and 47 patients had been reoperated with 40 reoperations due to SVD. The remaining 644 patients were invited for evaluation; 574 patients accepted and were evaluated for SVD. The incidence of SVD was calculated using competing risk regression analysis with death as the competing event.

RESULTS

A total of 173 patients were diagnosed with SVD by echocardiography. Of these, 64 (11%) patients had severe SVD and 109 (19%) patients moderate SVD. Severe SVD was associated with the age of the prosthesis and small prosthesis size [Size 21: hazard ratio (95% confidence interval, CI) 2.72 (0.97-8.56), P = 0.06; Size 19: 6.26 (1.63-24.06), P = 0.008]. The cumulative incidences of reoperation or severe SVD at Year 9 were 12.5% for Size 19, 7.6% for Size 21 and 3.1 (1.2-6.4)% for Size 23. Median survival in patients with prosthesis Sizes 23-29 was 6.4 (95% CI 5.7-7.0) years, with Size 21 it was 6.5 (95% CI 5.9-7.1) years and with Size 19 it was 6.9 (95% CI 5.7-8.2) years (P = 0.78).

CONCLUSIONS

The incidence of undetected severe SVD was as high as the incidence of operated SVD. The overall risk for SVD is high for the Mitroflow bioprosthesis, especially if the prosthesis is small and older than 5 years.

The Prognostic Significance of Patient-Prosthesis Mismatch after Aortic Valve Replacement

Patient-prosthesis mismatch (PPM) is a controversial issue in current clinical practice. PPM has been reported to have a negative impact on patients’ prognosis after aortic valve replacement in several studies, showing increased all-cause and cardiac mortality. Moreover, a close relationship has recently been described between PPM and structural valve deterioration in biological prostheses. In patients at risk for PPM, several issues should be considered, and in the current era of cardiac surgery, preoperative planning should consider the different types of valves available and the various surgical techniques that can be used to prevent PPM. The present paper analyses the state of the art of the PPM issue.

Can Perceval sutureless valve reduce the rate of patient-prosthesis mismatch?†

OBJECTIVES

The aim of this study is to compare the theoretical incidence of patient-prosthesis mismatch (PPM) in patients undergoing a sutureless or a sutured aortic valve replacement using an exact statistical matching.

METHODS

Between May 2012 and March 2016, 65 patients with severe symptomatic aortic stenosis underwent a sutureless aortic valve replacement with the Perceval bioprosthesis in 2 centres. Moreover, 177 aortic valve replacements with conventional sutured bioprosthesis were performed between August 2003 and September 2015. Perceval and sutured patients were 1:1 exactly matched for sex and body surface area (BSA), resulting in 62 couples (sutureless: BSA 1.77 ± 0.16 m 2 , female 62.9% vs sutured: BSA 1.77 ± 0.15 m 2 , female 62.9%).

RESULTS

After matching, the indexed effective orifice area was 1.50 ± 0.18 cm 2 /m 2 and 0.81 ± 0.19 cm 2 /m 2 in the sutureless and the sutured group, respectively ( P  < 0.001). No PPM occurred in patients who received a Perceval bioprosthesis ( n  = 62). In the sutured group ( n  = 62), 38 patients (61.3%) developed a PPM, which was moderate in 41.9% ( n  = 26) and severe in 19.4% ( n  = 12) ( P  < 0.001).

CONCLUSIONS

The indexed effective orifice area of the sutureless group was significantly larger than in the sutured one. The incidence of PPM with the conventional sutured biprosthesis was 61.3%, while it decreases to 0% in the sutureless group. No PPM was reported in the sutureless valve group. Therefore, the Perceval sutureless valve provides larger effective orifice areas compared to the sutured conventional bioprosthesis and could be considered as a good option to reduce the risk of a PPM.

Aortic valve anatomy and outcomes after transcatheter aortic valve implantation in bicuspid aortic valves

This original clinical research study id focused on description of baseline anatomy and outcomes after transcatheter aortic valve implantation (TAVI) in patients presenting with severe aortic stenosis (AS) and bicuspid aortic valve (BAV). We compared this BAV population with a population of patients with AS and tricuspid aortic valves after a propensity score matching developed by a multivariate logistic regression according to a non-parsimonious approach. Baseline anatomical characteristics were obtained by transthoracic echocardiography (TTE) and multi-sliced computed tomography (MSCT) and compared by chi-square and t-student tests. Outcomes were evaluated by correct fisher test at in hospital and 30 days follow-up. We found that BAV patients presents more complicated baseline anatomy as compared to patients with tricuspid valves. These anatomical features lead to higher procedural complications as the need for a second device implantation. However this does not translate into increase in mortality rate at 30 days follow-up but rather correlate to a lower device success rate.

The role and clinical implications of diastolic dysfunction in aortic stenosis

Diastolic dysfunction in aortic stenosis results primarily from left ventricular hypertrophy and myocardial fibrosis due to chronically elevated left ventricular systolic pressure. Currently, diastolic dysfunction does not have an explicit clinical role in management of patients with aortic stenosis. Studies have shown that improvement in diastolic dysfunction follows left ventricular remodelling after aortic valve replacement and that it occurs gradually or incompletely. Retrospective studies suggest that advanced grades of diastolic dysfunction at baseline are associated with increased mortality and adverse events even after aortic valve replacement. Recent studies have also associated myocardial fibrosis, a hallmark of diastolic dysfunction, with worse outcomes. In addition, these results were independent of the degree of aortic stenosis or valve replacement. Indirect evidence of the role of diastolic dysfunction in aortic stenosis also comes from paradoxical low-flow, low-gradient aortic stenosis, where disproportionate left ventricular hypertrophy leads to underfilling of the left ventricle, low-flow state and is associated with worse prognosis. Lastly, a limited number of studies suggest that worse diastolic dysfunction at baseline is detrimental in patients who develop aortic regurgitation after transcatheteraortic valve replacement, due to superimposition of volume overload on a stiff left ventricle. Current major limitations in our understanding of the prognostic role of diastolic dysfunction are the lack of universally accepted classification schemes, its dependence on dynamic loading conditions and the lack of larger prospective 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.

Comparison of the Performance of a Sutureless Bioprosthesis With Two Pericardial Stented Valves on Small Annuli: An In Vitro Study

BACKGROUND

Aortic valve replacement has evolved recently with the development of the sutureless bioprosthesis. One such valve is the Perceval bioprosthesis, which is built by mounting leaflets of bovine pericardium to a thin stent; this approach has the potential to provide an excellent fluid dynamic performance. We undertook an in vitro study to compare the hydrodynamic performance of the sutureless bioprosthesis with two standard pericardial stented bioprostheses (Crown and Magna).

METHODS

Tests were conducted using a mock loop, testing on two sizes of the three prostheses. The prosthesis sizes were chosen to house the valves in porcine aortic roots with a native annulus diameter of 19 mm (n = 6) or 21 mm (n = 6). The stroke volume ranged from 25 mL to 105 mL at a simulated heart rate of 70 beats per minute.

RESULTS

Mean pressure drop and energy loss rose with increasing stroke volume in all of the valves tested (p < 0.001), with the sutureless valve showing the lowest values for both variables (p < 0.001). Effective orifice area values were stable across the stroke volume intervals and were larger in the sutureless valves (p < 0.001).

CONCLUSIONS

All of the valves tested provided good fluid dynamic performances. The sutureless bioprosthesis provided the best performance with the least hindrance to flow behavior. From the hydrodynamic perspective, the sutureless prosthesis may present an advance in the evolution of bioprostheses, ensuring low gradients and potential for low incidence of patient-prosthesis mismatch even in small annuli.

Aortic valve prosthesis-patient mismatch and exercise capacity in adult patients with congenital heart disease

OBJECTIVES

To report the prevalence of aortic valve prosthesis-patient mismatch (PPM) in an adult population with congenital heart disease (CHD) and its impact on exercise capacity. Adults with congenital heart disease (ACHD) with a history of aortic valve replacement may outgrow their prosthesis later in life. However, the prevalence and clinical consequences of aortic PPM in ACHD are presently unknown.

METHODS

From the national Dutch Congenital Corvitia (CONCOR) registry, we identified 207 ACHD with an aortic valve prosthesis for this cross-sectional cohort study. Severe PPM was defined as an indexed effective orifice area ≤0.65 cm2/m2 and moderate PPM as an indexed orifice area ≤0.85 cm2/m2 measured using echocardiography. Exercise capacity was reported as percentage of predicted exercise capacity (PPEC).

RESULTS

Of the 207 patients, 68% was male, 71% had a mechanical prosthesis and mean age at inclusion was 43.9 years ±11.4. The prevalence of PPM was 42%, comprising 23% severe PPM and 19% moderate PPM. Prevalence of PPM was higher in patients with mechanical prostheses (p<0.001). PPM was associated with poorer exercise capacity (mean PPEC 84% vs. 92%; p=0.048, mean difference =-8.3%, p=0.047). Mean follow-up was 2.6±1.1 years during which New York Heart Association (NYHA) class remained stable in most patients. PPM showed no significant effect on death or hospitalisation during follow-up (p=0.218).

CONCLUSIONS

In this study we report a high prevalence (42%) of PPM in ACHD with an aortic valve prosthesis and an independent association of PPM with diminished exercise capacity.

Incidence and Impact of Patient-Prosthesis Mismatch in Isolated Aortic Valve Surgery

AIM:

The mains topics of this work are the incidence of patient-prosthesis mismatch and the influence in the early results of isolated aortic valve surgery.

METHODS:

In 193 patients isolated aortic valve surgery was performed. The study population was divided in three subgroups: 20 patients with severe, 131 patients with moderate and 42 patients without patient-prosthesis mismatch. The indexed effective orifice area was used to define the subgroups. Operative mortality and perioperative complications were considered the indicators of the early results of aortic valve surgery.

RESULTS:

The incidence of severe and moderate patient-prosthesis mismatch was respectively 10.3% and 67.8%. Hospital mortality and perioperative complications were: mortality 5% vs. 3.1% vs. 2.4% (p = 0.855), low cardiac output 5% vs. 6.9% vs. 4.8% (p = 0.861); pulmonary complications 5% vs. 3.1 vs. 0.0% (p = 0.430); exploration for bleeding 5% vs. 0.8% vs. 2.4% (p = 0.319); atrial fibrillation 30% vs. 19.8% vs. 11.9% (p = 0.225); wound infection 5% vs. 0.8% vs. 0.00% (p = 0.165), respectively for the group with severe, moderate and without patient-prosthesis mismatch.

CONCLUSIONS:

Patient-prosthesis mismatch is a common occurrence in aortic valve surgery. This phenomenon does not affect the early results of aortic valve surgery.

Prosthesis-patient mismatch causes a significantly increased risk of operative mortality in aortic valve replacement

BACKGROUND

Small aortic prosthesis can lead to prosthesis-patient mismatch (PPM). Implanting such small prosthesis remains a controversial issue. This study was done to investigate whether or not PPM causes an increased operative mortality in aortic valve replacement (AVR).

METHODS

Two-hundred-two consecutive patients undergoing primary AVR in a tertiary hospital were included. The sample was grouped according to the aortic valve prosthesis size: ≤21 mm (small) and >21 mm (standard). The effect of variables on outcomes was determined by univariate and multivariable regression analyses.

RESULTS

PPM was found significantly more among patients with AVR ≤ 21 mm (P < 0.0001). Moreover, the likelihood of mortality also was significantly higher in these patients (P < 0.0001). Univariate analysis demonstrated small prosthesis size, urgent operation, PPM, female gender, and NYHA Class IV as significant predictors of mortality. Multivariate regression identified female gender, PPM, and urgent operation as the key independent predictors of mortality.

CONCLUSION

PPM and female gender are significant predictors of mortality. Care should be taken to prevent PPM by implanting larger prosthesis especially in females.