Severe prosthesis-patient mismatch after aortic valve replacement for aortic stenosis: Analysis of risk factors for early and long-term mortality

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.

Aortic root enlargement in patients undergoing mitral and aortic replacement: early outcomes in a sub-Saharan population

Introduction

Aortic root enlargement (ARE) is often required to avoid patient-prosthesis mismatch (PPM) in young patients undergoing aortic surgery, including those undergoing combined mitral and aortic valve replacement (double valve replacement, DVR). Adding ARE to DVR may increase the operative risk by extending the surgical time. Herein, we review our experience with ARE in patients who underwent DVR.

Materials and methods

The medical records of 69 patients who underwent DVR at our institution between February 2008 and November 2021 were retrospectively reviewed. The patients were divided into two groups according to the ARE procedure (ARE-DVR: 25 patients; DVR: 44 patients). Descriptive and comparative analyses of demographic, clinical, and surgical data were performed.

Results

Among the 69 patients who underwent DVR, 35 were women (sex ratio, 0.97). The mean age at surgery was 26.7  ±  13.9 years (range: 7-62 years). Among the 47 patients aged ≤30 years, 40.4% (19/47) were aged between 10 and 20 years, and 6.3% (3/47) were aged <10 years. Patients in the ARE-DVR group were younger (23.3 ± 12.9 years vs. 28.5 ± 14.2 years, p < 0.05). The New York Heart Association Class ≥III dyspnea was the most common symptom (89.9%), with no differences between the two groups. Of all the patients, 84.1% had sinus rhythm. Rheumatic disease was the most common etiology in the entire cohort (91.3%). The mean aortic annulus diameter was 20.54 mm, with smaller sizes found in the ARE-DVR group (18.00 ± 1.47 mm vs. 22.50 ± 2.35 mm, p < 0.05). The aortic cross-clamping duration was greater in the ARE-DVR group (177.6 ± 37.9 min vs. 148.3 ± 66.3 min, p = 0.047). The operative mortality rate was 5.6% for the entire cohort (ARE-DVR: 8% vs. DVR: 4.5%, p = 0.46). Among the patients who underwent echocardiographic control at follow-up, the mean aortic gradient was 19.6 ± 7.2 mmHg (range: 6.14-33 mmHg), with no differences among the groups.

Conclusion

The association between ARE and DVR did not significantly affect operative mortality. ARE can be safely used whenever indications arise to reduce the occurrence of PPM, especially in young patients with growth potential.

Intermediate Follow-Up of Balloon-Expandable Versus Self-Expanding Transcatheter Aortic Valve Implantation in Patients With Small Aortic Annuli

The clinical impact of prosthesis-patient mismatch (PPM) in patients with small aortic annuli who underwent transcatheter aortic valve (AV) implantation with either balloon-expandable (BE) or self-expanding (SE) valves remains controversial. We assessed in-hospital and intermediate clinical outcomes in 573 patients with transfemoral transcatheter AV implantation with a small AV annulus, defined as an AV annulus area ≤430 mm². A total of 337 patients treated with a 23-mm BE valve (SAPIEN 3, Ultra) were compared with 236 patients treated with a 26-mm SE valve (Evolut series). Valve-in-valve cases were excluded, and late echo follow-up (mean 674 ± 438 days) was assessed in a subset of 292 patients (51.0%). Well-matched BE and SE cohorts did not differ with respect to major in-hospital outcomes, other than a borderline increase in vascular complications and composite bleeding in patients with SE. Patients with BE had a higher incidence of severe PPM on discharge echocardiography (16.9% vs 6.8%, p <0.002). The mean AV gradient at 30 days was higher for patients with BE (12.2 ± 4.2 vs 6.2 ± 7.9 mm Hg, p <0.001) and at late follow-up (14.0 ± 8.2 vs 7.2 ± 3.5 mm Hg, p <0.001). The follow-up left ventricular ejection fraction and incidence of >mild aortic insufficiency were similar. All-cause mortality for the 2 cohorts was similar, with an overall mean (95% confidence interval) survival time of 61.2 months (57.8 to 64.5; p = 0.98). There were no significant survival differences between combined patients with BE and SE with no, moderate, or severe PPM, with an overall mean (95% confidence interval) survival time of 32.5 (30.5 to 34.5) months combining valve types (p = 0.23). In conclusion, despite an increased incidence of PPM with higher mean AV gradients that persist on late echocardiography in the BE cohort, patients with BE and SE with small aortic annuli have similar clinical outcomes at intermediate follow-up. Moderate and severe PPM had no impact on survival at a mean follow-up of 32.5 months.

Rapid-Deployment Aortic Valve Replacement: Patient Selection and Special Considerations

Sutureless or rapid deployment valves in the setting of aortic valve replacement (AVR) is an emerging surgical technique using the transcatheter valve technology, which may lead to reduction in cross-clamp time and potentially better hemodynamics compared to a stented bioprosthetic valve. The absence of subannular pledgets results to excellent hemodynamic performance with reduced turbulent flow and larger effective orifice area. However, complications from both surgical and transcatheter AVR may still occur and impact survival. The incidence of paravalvular leakage and permanent pacemaker implantation are not low. Although technical modifications can improve these outcomes, there is a learning curve effect. Therefore, technical and anatomical considerations as well as better patient selection are paramount for better outcomes. In this review, we discuss the use of sutureless or rapid deployment valves in setting of (1) complex procedures, (2) minimally invasive AVR, and (3) small aortic annulus. The advantage of sutureless or rapid deployment valves in terms of mortality remains to be clarified; therefore, it is necessary to accumulate long-term outcomes in an appropriate patient cohort.

Patient Prosthesis Mismatch After SAVR and TAVR

Patient-prosthesis mismatch (PPM) remains one out of many factors to be considered during decision-making for the treatment of aortic valve pathologies. The idea of adequate sizing of a prosthetic heart valve was established by Rahimtoola already in 1978. In this article, the author described the phenomenon that the orifice area of a prosthetic heart valve may be too small for the individual patient. PPM is assessed by measurement or projection of the prosthetic effective orifice area indexed to body surface area (iEOA), while it is recommended to use different cut point values for non-obese and obese patients for the categorization of moderate and severe PPM. Several factors influence the accuracy of both the projected and the measured iEOA for PPM assessment, which leads to a certain number of false assignments to the PPM or no PPM group. Despite divergent findings on the impact of PPM on clinical outcomes, there is consensus that PPM should be avoided to prevent sequelae of increased prosthetic gradients after aortic valve replacement. To prevent PPM, it is required to anticipate the iEOA of the prosthesis prior to the procedure. The use of adequate reference tables, derived from echocardiographically measured mean effective orifice area (EOA) values from preferably large numbers of patients, is most appropriate to predict the iEOA. Such tables should be used also for transcatheter heart valves in the future. During the decision-making process, all available options should be taken into account for the individual patient. If the predicted size and type of a surgical prosthesis cannot be implanted, additional surgical procedures, such as annular enlargement with the Manougian technique, or alternative procedures, such as transcatheter aortic valve implantation (TAVI) can prevent PPM. PPM prevention for TAVI patients is a new field of interest and includes anticipation of the iEOA, prosthesis selection, and procedural strategies.

Hemodynamically significant prosthesis-patient mismatch can be predicted and is associated with early prosthetic valve dysfunction in aortic bioprosthesis

OBJECTIVES

To evaluate the accuracy of predicted prosthesis-patient mismatch (PPM) regarding actual PPM measured postoperatively. To assess the association between PPM and prosthetic valve dysfunction.

METHODS

Retrospective cohort study including adult patients after aortic valve replacement surgery with a biological prosthesis. Predicted PPM status was determined using mean reference effective orifice area indexed to total body surface (iEOA), without considering reference standard deviations. Postoperative PPM status was determined by measuring iEOA within the first 60 postoperative days. Prosthetic valve dysfunction was defined as thrombosis, pannus, valve degeneration, and/or disruption.

RESULTS

205 patients were enrolled between January 2003 and June 2017: predicted PPM was absent in 52 patients (25.4%), moderate in 137 patients (66.8%), and severe in 16 patients (7.8%). After surgery, the actual postoperative iEOA was measured: 53 (25.9%) did not have PPM, 73 had moderate PPM (35.6%), and 79 had severe PPM (38.5%). Predicted PPM identified the presence of hemodynamically significant actual postoperative PPM (OR = 2.56; 95%CI 1.30-5.05; P = .006), though not its degree of severity. Prosthetic valve dysfunction was more frequent among patients with hemodynamically significant PPM (53.9% vs. 11.3%; P < .001), compared to those without PPM. The association between PPM and prosthetic valve dysfunction was maintained after adjusting for gender, age, and ever-smoking (OR = 9.03; P < .001). The incidence of thrombosis or pannus was also nonsignificantly higher in patients with moderate or severe PPM.

CONCLUSIONS

Predicted PPM identifies the presence, possibly not the severity, of actual postoperative PPM. Moderate or severe PPM is associated with prosthetic valve dysfunction. Actual postoperative prosthesis-patient mismatch measured within 60 postoperative days showed a distinctive hemodynamic profile and presented a stronger association with prosthetic valve dysfunction than predicted prosthesis-patient mismatch. A. Echocardiographic follow-up in patients according to the actual postoperative PPM measured within 60 postoperative days. B. Prediction of prosthetic valve dysfunction based on preoperative predicted PPM or on actual postoperative PPM within 60 postoperative days. PPM: prosthesis-patient mismatch. OR: Odds ratio.

The impact of patient-prosthesis mismatch on early and long-term survival after aortic replacement with the Edwards Perimount valve: A propensity score-matched analysis

BACKGROUND

To investigate the impact of severe patient-prosthesis mismatch (PPM) related to the Edwards Lifesciences Perimount (EP) bioprosthesis in the aortic position on early in-hospital outcomes and long-term survival.

METHODS

A total of 5964 consecutive patients underwent aortic valve replacement at the Bristol Heart Institute between 1998 and 2014, 2667 representing the cohort of this study received EP. PPM was defined severe as EOAi < 0.65 cm² /m² . To minimize bias, propensity score matching was conducted and two groups A and B (without and with severe PPM) of 320 patients with similar preoperative characteristics were matched. We assessed early in-hospital outcomes including CVA, re-exploration for bleeding, low cardiac output, wound infection, acute renal injury, length of hospital stay, and long-term survival for both groups in unmatched and matched populations.

RESULTS

In the unmatched analysis, 18.3% of patients had severe PPM. Severe PPM was not associated with increased in-hospital mortality (4.5% vs. 2.9%, respectively, p = .09) or any other early adverse outcomes except increased length of hospital stay (10.57 ± 8.2 vs. 11.7 ± 9.4, respectively, p = .01). Long-term survival differed significantly between groups at 2 and 8 years (91.8% vs. 91.4% and 60.5% vs. 55.7%, respectively, p = .02). Matched analysis showed no differences between the groups in early health outcomes and overall survival at 2 and 8 years was also similar (89.7% vs. 91% and 57.3% vs. 58%, group A vs. B, respectively p = .9).

CONCLUSION

Presence of PPM does not seem to affect early in-hospital outcomes or late survival when using EP in patients undergoing aortic valve replacement.

Sutureless valve and rapid deployment valves: a systematic review and meta-analysis of comparative studies

Background

The treatment of aortic valve disease is the most common valvular surgery in industrialized nations, with 3-9% of the population over the age of eighty having at least moderate aortic stenosis. As transcatheter aortic valve replacement (TAVR) has become more established, newer surgical prostheses have been developed with a variety of anchoring systems that do not rely solely on sutures to hold the valve in an appropriate position. The Edwards Intuity valve is a bovine pericardial prosthesis that is modelled on the widely implanted Perimount MagnaEase aortic prosthesis. The Perceval valve is a bovine pericardial valve attached to a self-expanding nitinol stent, which uses the radial force exerted on the patient's aortic annulus and aortic root by the stent portion to hold the valve in position. This meta-analysis compares the outcomes of comparative studies of these two valve systems.

Methods

This systematic review and meta-analysis compares the outcomes of rapid deployment valves (RDV) and sutureless valves (SURD) and was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations and guidance. The search strategy interrogated six electronic databases. Outcomes measured included all-cause mortality at latest follow up, stroke, cross-clamp and cardiopulmonary bypass (CPB) times, pacemaker implantation rates, paravalvular leak and post-operative transvalvular gradient.

Results

The search strategy identified 407 unique papers for initial assessment with seven studies qualifying for inclusion in the analysis. The outcomes of 4,076 patients (1,650 RDV, 2,426 SURD) were included. There was no difference in mortality, stroke or moderate or worse paravalvular regurgitation between the two groups. SURD had significantly shorter CPB time by 15.7 minutes [95% confidence interval (CI): 4.2-27.1; P=0.007] and a shorter cross-clamp time by 11.3 minutes (95% CI: 6.3-16.3; P<0.001) compared to RDV. RDV had a lower post-operative transvalvular gradient by 2.5 mmHg (95% CI: 1.2-3.8; P<0.001) and a lower rate of mild paravalvular regurgitation (OR 2.51; 95% CI: 1.435-4.768; P=0.004).

Conclusions

Both valve types have an adequate safety profile and are comparable to conventional sutured prostheses. There was a significant reduction in cross-clamp and CPB times associated with SURD. This may be of benefit for patients requiring multiple concomitant procedures and increases the utility of minimally invasive valve replacement. However, SURD was associated with higher post-operative transvalvular gradients and a higher incidence of paravalvular regurgitation.

Clinical outcomes and hemodynamic performance of Dafodil™ aortic and mitral pericardial bioprosthesis: 1-year results from Dafodil-1 first-in-human trial

BACKGROUND

Bioprosthesis has been increasingly implanted for the treatment of transvalvular disease across the world. A new Dafodil™ pericardial bioprosthesis (Meril Life Sciences Pvt. Ltd., India) recently approved by Conformité Européenne (CE) is a tri-leaflet, stented, bovine valve. The purpose of Dafodil-1 first-in-human trial was to evaluate clinical safety and performance (including hemodynamic parameters) of the Dafodil pericardial bioprosthesis in patients who underwent aortic or mitral valve replacement.

METHODS

This prospective, multicenter clinical trial enrolled 60 patients (Aortic: 30 patients; Mitral: 30 patients) from seven sites across India. Safety endpoints were early (≤30 days) and late (> 30 days) mortality and valve-related morbidity. The performance endpoints were hemodynamic performance, improvement in NYHA functional class, and change in the quality of life using SF-12v1 health survey.

RESULTS

From July 2017 to July 2018, 60 patients underwent implantation of the Dafodil pericardial bioprosthesis. Post-operatively, NYHA functional class significantly improved in all the patients (Aortic: 90% NYHA class-I and 10% NYHA class-II; Mitral: 96.55% NYHA class-I and 3.45% NYHA class-II; P < 0.001). There was no death in aortic valve replacement patients till 12-month. In mitral valve replacement patients, early mortalities occurred in three patients, and late mortality occurred in one patient; none of these were valve-related. Freedom from all-cause mortality reported was 93.33% at 12-month. Mean aortic pressure gradient decreased from 52.71 ± 24.47 mmHg [with 0.89 ± 0.70 cm² effective orifice area (EOA)] pre-operatively to 14.49 ± 6.58 mmHg (EOA: 1.85 ± 0.27 cm²) at 12-month. Overall, the mitral mean pressure gradient and EOA were 4.41 ± 1.69 mmHg and 2.67 ± 0.48 cm², respectively, at 12-month. Significant improvement (P < 0.05) in the patients' quality of life was reported at all follow-ups.

CONCLUSIONS

The clinical safety and performance of the Dafodil pericardial bioprosthesis were favourable at 12-month. Moreover, a study with a larger patient population and longer follow-up is warranted to further assess the device.

TRIAL REGISTRATION

Dafodil-1 trial has been prospectively registered on 10/07/2017 under Clinical Trial Registry-India (http://www.ctri.nic.in). (Registration number: CTRI/2017/07/009008).

The effect of patient-prosthesis mismatch on survival after aortic and mitral valve replacement: a 10 year, single institution experience

Background

The evidence on the impact of patient-prosthesis Mismatch (PPM) on survival thus far has been conflicting. The aim of this study was to 1) study the effect of PPM on survival after isolated aortic and mitral valve replacement and 2) Assess the interaction between left ventricular function and PPM on survival.

Methods

The study cohort was patients who underwent isolated Aortic valve replacement (AVR) and Mitral valve replacement (MVR) over a 10-year period from 2008 to 2018. PPM was defined using the projected indexed effective orifice area (EOAi). The cohort was divided into different groups based on the degree of PPM. The severity of PPM was classified using threshold values of EOAi used in the literature. The Kaplan- Meier method was used to compare survival by degree of PPM. Multivariate Cox proportional hazards models were used to generate adjusted hazard ratios (HR) with 95% confidence intervals. An interactive term for ejection fraction (EF) was added to test whether EF modifies the effect of the PPM grade on survival. In addition, sub-group analysis based on left ventricular function was performed.

Results

In the AVR cohort, there were a total of 1953 patients. The distribution of patients in the different PPM categories was as follows: no PPM 59.7%; moderate PPM 36.8%; severe PPM 3.5%. There was no significant difference in survival between the different groups. At 10 years, the adjusted HR between patients with severe PPM versus no PPM was 1.1(CI 0.5–2.4, p >  0.05) and the HR between those with moderate PPM versus no PPM was 0.97 (CI 0.74–1.23, p >  0.05). In the MVR cohort, there were a total of 298 patients. The distribution of PPM is as follows: no PPM 59.4%; and with PPM 40.6%. Again, there was no significant difference in survival between the groups. At 5 years, the adjusted HR between patients with PPM versus no PPM was 1.45 (CI 0.67–3.14, p >  0.05). In both groups, there was no significant interaction between left ventricular function (LVF) and degree of PPM on survival.

Conclusions

In our study cohort, the degree of PPM was not an independent predictor of survival after AVR or MVR. There was also no significant interaction between LV function and degree of PPM on survival.

Determinants of Aortic Prosthesis Mismatch in a Brazilian Public Health System Hospital: Big Patients or Small Prosthesis?

Background

Prosthesis-patient mismatch (PPM) is associated with worse outcomes.

Objective

Determine the frequency and evaluate preoperatory variables independently associated with severe PPM in a tertiary hospital focused on Public Health Care.

Methods

A total of 316 patients submitted to aortic valve replacement, who had echocardiography performed within the first 30 days after surgery, were retrospectively analyzed. The indexed effective orifice area (iEOA) of the prosthesis was used to classify the patients into three groups, according to PPM, considering body mass index (BMI): severe PPM (iEOA) < 0.65 cm²/m²), mild to moderate PPM (iEOA, 0.65 cm²/m² - 0.85 cm²/m²) and without PPM (iEOA > 0.85 cm²/m²) for a BMI < 30 kg/m² and severe PPM (iEOA) < 0.55 cm²/m²), mild to moderate (iEOA, 0.55 cm²/m²- 0.70 cm²/m²) and without PPM (iEOA > 0.7 cm²/m²) for a BMI > 30 kg/m². Statistical significance was considered when p < 0.05.

Results

iEOA was obtained in 176 patients. The frequency of severe and moderate PPM was 33.4% and 36.2%, respectively. Severe PPM patients were younger and had larger BMI, but smaller left ventricular outflow tract diameter (LVOTD). The independent variables used to predict severe PPM were male gender, BMI > 25 kg/m², age < 60 years, LVOTD < 21 mm, and rheumatic etiology with an area under the ROC curve of 0.82.

Conclusion

The frequency of severe PPM is high in a Brazilian population representative of the Public Health System, and it is possible to predict PPM from preoperative variables such as rheumatic valvular disease, gender, BMI, age and LVOTD.

Safety, efficacy, and hemodynamic performance of a stented bovine pericardial aortic valve bioprosthesis: Two-year analysis

OBJECTIVES

The study objectives were to evaluate the safety, efficacy, and hemodynamic performance of a novel stented bovine pericardial aortic valve bioprosthesis 2 years after implantation.

METHODS

The PERIcardial SurGical AOrtic Valve ReplacemeNT Pivotal Trial enrolled patients with symptomatic moderate/severe aortic stenosis or regurgitation at centers in Canada, Europe, and the United States. We report the outcomes and hemodynamic performance in patients with up to 2 years of follow-up.

RESULTS

A total of 1273 patients were enrolled, and 1110 underwent implantation. Among patients undergoing implantation, the mean age was 70.2 ± 8.9 years; 833 (75.0%) were male. Risk of mortality (Society of Thoracic Surgeons) was 2.0% ± 1.4%. At the time of analysis, 604 patients had completed the 2-year follow-up visit. Linearized late event rates were as follows: all death, 2.68%; valve-related death, 0.42%; valve thrombosis, 0.05%; endocarditis, 0.94%; thromboembolism, 1.68%; all hemorrhage, 2.94%; major hemorrhage, 1.99%; all paravalvular leak, 0.26%; and major paravalvular leak, 0.05% per patient-year. Mean 2-year aortic gradient and effective orifice area were 13.4 ± 5.0 mm Hg and 1.5 ± 0.37 cm², respectively. Moderate and severe prosthesis-patient mismatch were observed in 43.5% and 34.8% of patients at 2 years, respectively. Improvement in New York Heart Association class compared with baseline was observed in 73.0% with moderate mismatch and 74.1% with severe mismatch.

CONCLUSIONS

The Avalus (Medtronic, Minneapolis, Minn) bovine pericardial valve demonstrates good clinical and safety outcomes at 2 years. Hemodynamic performance shows mean gradients comparable to currently available bovine pericardial aortic valves. There was no clinical impact of moderate to severe mismatch at 2 years. Further follow-up is required to evaluate midterm to long-term clinical outcome.

A mechanistic investigation of the EDWARDS INTUITY Elite valve's hemodynamic performance

OBJECTIVE

Rapid deployment surgical aortic valve replacement has emerged as an alternative to the contemporary sutured valve technique. A difference in transvalvular pressure has been observed clinically between RD-SAVR and contemporary SAVR. A mechanistic inquiry into the impact of the rapid deployment valve inflow frame design on the left ventricular outflow tract and valve hemodynamics is needed.

METHODS

A 23 mm EDWARDS INTUITY Elite rapid deployment valve and a control contemporary, sutured valve, a 23 mm Magna Ease valve, were implanted in an explanted human heart by an experienced cardiac surgeon. Per convention, the rapid deployment valve was implanted with three non-pledgeted, simple guiding sutures, while fifteen pledgeted, mattress sutures were used to implant the contemporary surgical valve. In vitro flow models were created from micro-computed tomography scans of the implanted valves and surrounding cardiac anatomy. Particle image velocimetry and hydrodynamic characterization experiments were conducted in the vicinity of the valves in a validated pulsatile flow loop system.

RESULTS

The rapid deployment and control valves were found to have mean transvalvular pressure gradients of 7.92 ± 0.37 and 10.13 ± 0.48 mmHg, respectively. The inflow frame of the rapid deployment valve formed a larger, more circular, left ventricular outflow tract compared to the control valve. Furthermore, it was found that the presence of the control valve's sub-annular pledgets compromised its velocity distribution and consequently its pressure gradient.

CONCLUSIONS

The rapid deployment valve's intra-annular inflow frame provides for a larger, left ventricular outflow tract, thus reducing the transvalvular pressure gradient and improving overall hemodynamic performance.

Patient-prosthesis mismatch following aortic valve replacement

Patient-prosthesis mismatch (PPM) occurs when an implanted prosthetic valve is too small for the patient; severe PPM is defined as an indexed effective orifice area (iEOA) <0.65 cm2/m2 following aortic valve replacement (AVR). This review examines articles from the past 10 years addressing the prevalence, outcomes and options for prevention and treatment of PPM after AVR. Prevalence of PPM ranges from 8% to almost 80% in individual studies. PPM is thought to have an impact on mortality, mainly in patients with severe PPM, although severe PPM accounts for only 10–15% of cases. Outcomes of patients with moderate PPM are not significantly different to those without PPM. PPM is associated with higher rates of perioperative stroke and renal failure and lack of left ventricular mass regression. Predictors include female sex, older age, hypertension, diabetes, renal failure and higher surgical risk score. PPM may be a marker of comorbidity rather than a risk factor for adverse outcomes. PPM should be suspected in patients with persistent cardiac symptoms after AVR when there is high prosthetic valve velocity or gradient and a small calculated effective orifice area. After exclusion of other causes of increased transvalvular gradient, re-intervention may be considered if symptoms persist and are unresponsive to medical therapy. However, this decision needs to consider the available options to relieve PPM and whether expected benefits justify the risk of intervention. The only effective intervention is redo surgery with implantation of a larger valve and/or annular enlargement. Therefore, focus needs to be on prevention.

Aortic root enlargement to mitigate patient-prosthesis mismatch: do early adverse events justify reluctance?†

OBJECTIVES:

Concomitant aortic root enlargement (ARE) at the time of surgical aortic valve replacement can be performed to avoid patient-prosthesis mismatch, an important predictor of adverse long-term outcome.

METHODS:

We performed a single-centre, retrospective analysis of 4120 patients receiving isolated aortic valve replacement, of whom 171 (4%) had concomitant ARE between January 2005 and December 2015. The analysis of postoperative outcome and early mortality was performed. Owing to inequality of the groups, patients were matched 1:1.

RESULTS:

The mean age of all 4120 patients was 68.8 ± 10.5 years, and comorbidities were equally balanced after matching. The mean aortic cross-clamp time, cardiopulmonary bypass time and total operative time were prolonged by 19, 20 and 27 min in the ARE group, respectively. Early mortality was not statistically significantly different with 1.4% in the surgical aortic valve replacement and 1.8% in the ARE group. Postoperative complications were <5% in all matched 338 patients: bleeding (3% vs 3%), pericardial effusion (3.0% vs 4.2%), sternal instability (1.8% vs 0%) and sternal wound infection (3.0% vs 1.2%). A significant higher number of patients had respiratory failure after ARE (unmatched: 17.1% vs 9.9%, P < 0.001; matched: 18.3% vs 9.5%, P = 0.028). Factors independently associated with overall mortality were age [hazard ratio (HR) 1.71], chronic obstructive pulmonary disease (HR 1.47), diabetes (HR 1.82), atrial fibrillation (HR 2.14) and postoperative respiratory failure (HR 2.84).

CONCLUSIONS:

ARE can be performed safely in experienced centres with no significant increase in the risk of early postoperative surgical complications and early mortality. However, the surgeon and the intensive care unit team should be aware of an increased risk for postoperative respiratory failure in ARE patients.

Trifecta has lower gradient and less prosthesis-patient mismatch than Mosaic Ultra in the aortic position: A prospective randomized study

OBJECTIVE

When aortic valve replacement is needed, a biological valve is usually implanted in patients older than age 60 to 65 years. A large valvular opening area is important to avoid prosthesis-patient mismatch and facilitate reverse left ventricular remodeling. The Trifecta biological valve (St Jude Medical, St Paul, Minn) is, because of its design, believed to reduce transvalvular gradient compared with other biological valves, especially in smaller annuli. Several retrospective studies have compared transvalvular gradients of implanted valves prostheses using the respective manufacturers given size and not the actual annulus size measured by a metric sizer. This makes comparison of the hemodynamic properties of different valve brands and sizes difficult. We therefore performed a prospective randomized study, using the same metric sizer to measure annulus size, and compared hemodynamic profiles of the Trifecta to our standard Mosaic Ultra biological valve (Medtronic, Minneapolis, Minn).

METHODS

Ninety elective patients with small to medium annulus diameter undergoing aortic valve replacement were randomized to either Trifecta or Mosaic Ultra. After native valve removal and decalcification, a Hegar-sizer was used to measure true annulus size. Then the largest possible valve of either brand was implanted according to the randomization protocol. Echocardiography was performed 6 months postoperatively.

RESULTS

Baseline parameters of the 2 cohorts were comparable. There were lower transvalvular gradients in the Trifecta compared with the Mosaic Ultra group for the given annulus sizes. Severe prosthesis-patient mismatch was present in 28% of patients in the Mosaic group and 3% of patients in the Trifecta group.

CONCLUSIONS

Trifecta showed lower transvalvular gradients and less severe prosthesis-patient mismatch compared with Mosaic Ultra for the given annulus sizes. ClinicalTrials.gov Protocol ID: 2011/2596/REK.

Outcomes of a Rapid Deployment Aortic Valve versus its Conventional Counterpart

Objective

The aim of this study was to compare outcomes after rapid-deployment aortic valve replacement (RDAVR) and conventional aortic valve replacement (AVR) from two studies.

Methods

Patients who underwent RDAVR (INTUITY valve) in the prospective, 5-year, single-arm multicenter TRITON study, or conventional AVR (Perimount Magna Ease valve) in the prospective Perimount Magna Ease postmarket study, were propensity score matched and compared for procedural, hemodynamic, safety, and clinical outcomes.

Results

Matched RDAVR (n = 106) and conventional AVR (n = 106) patients had similar baseline characteristics (mean ± SD age, 72.8 ± 7.6 vs 72.5 ± 7.4 years; male 59.4% vs 61.3%) and procedures (concomitant procedures: 41.5% vs 50.9%). Mean ± SD aortic cross-clamp time was significantly shorter in RDAVR than AVR patients (51.8 ± 20.9 vs 73.9 ± 33.2 minutes; P < 0.001), as was mean cardiopulmonary bypass time (82.8 ± 34.2 vs 102.4 ± 41.7 minutes; P < 0.001). At 1 year, RDAVR patients showed significantly lower mean ± SD and peak aortic valve gradients (9.0 ± 3.4 and 17.0 ± 6.2 mm Hg, respectively) than conventional AVR patients (13.4 ± 5.5 and 24.2 ± 10.8 mm Hg, respectively; all P < 0.001). Patient-prosthesis mismatch was significantly less common with RDAVR than with AVR [overall: 16/66 (24.2%) vs 46/76 (60.5%); P = 0.007; severe: 2/66 (3.0%) vs 13/76 (17.1%)]. There were no significant differences between the RDAVR and AVR groups regarding 30-day safety endpoints. Survival rates in the RDAVR and conventional AVR groups were, respectively, 99.1% and 100.0% at 30 days, 97.1% and 95.1% at 1 year, and 93.3% and 94.1% at 3 years ( P = nonsignificant).

Conclusions

In this retrospective study with matched populations, the RDAVR with the INTUITY valve system provided superior procedural and hemodynamic outcomes than a standard bioprosthesis without compromising safety.