Examining the typical hemodynamic performance of nearly 3000 modern surgical aortic bioprostheses.

OBJECTIVES: The objective of this analysis was to assess the normal haemodynamic performance of contemporary surgical aortic valves at 1 year postimplant in patients undergoing surgical aortic valve replacement for significant valvular dysfunction. By pooling data from 4 multicentre studies, this study will contribute to a better understanding of the effectiveness of surgical aortic valve replacement procedures, aiding clinicians and researchers in making informed decisions regarding valve selection and patient management. METHODS: Echocardiograms were assessed by a single core laboratory. Effective orifice area, dimensionless velocity index, mean aortic gradient, peak aortic velocity and stroke volume were evaluated. RESULTS: The cohort included 2958 patients. Baseline age in the studies ranged from 70.1 ± 9.0 to 83.3 ± 6.4 years, and Society of Thoracic Surgeons risk of mortality was 1.9 ± 0.7 to 7.5 ± 3.4%. Twenty patients who had received a valve model implanted in fewer than 10 cases were excluded. Ten valve models (all tissue valves; n = 2938 patients) were analysed. At 1 year, population mean effective orifice area ranged from 1.46 ± 0.34 to 2.12 ± 0.59 cm2, and dimensionless velocity index, from 0.39 ± 0.07 to 0.56 ± 0.15. The mean gradient ranged from 8.6 ± 3.4 to 16.1 ± 6.2 mmHg with peak aortic velocity of 1.96 ± 0.39 to 2.65 ± 0.47 m/s. Stroke volume was 75.3 ± 19.6 to 89.8 ± 24.3 ml. CONCLUSIONS: This pooled cohort is the largest to date of contemporary surgical aortic valves with echocardiograms analysed by a single core lab. Overall haemodynamic performance at 1 year ranged from good to excellent. These data can serve as a benchmark for other studies and may be useful to evaluate the performance of bioprosthetic surgical valves over time. CLINICAL TRIAL REGISTRATION NUMBER: NCT02088554, NCT02701283, NCT01586910 and NCT01531374.

Outcomes of Surgical Bioprosthetic Aortic Valve Replacement in Patients Aged ≤65 and >65 Years.

BACKGROUND: Implantation of a bioprosthetic valve is a reasonable choice for patients aged > 65 years. For middle-aged patients there is less certainty about whether a mechanical or bioprosthetic valve is best. METHODS: The Pericardial Surgical Aortic Valve Replacement (PERIGON) Pivotal Trial is evaluating the safety and efficacy of the Avalus bioprosthesis (Medtronic). We evaluated clinical and echocardiographic outcomes through 5 years of follow-up, stratified by age ≤ 65 and >65 years. RESULTS: Two hundred seventy-one patients (24.2%) were ≤65 years old and 847 (75.8%) >65 years old. Most patients in both groups were men (217 [80.1%] vs 623 [73.6%], respectively; P = .031). Younger patients had a lower Society of Thoracic Surgeons risk of mortality (1.1% ± 0.9% vs 2.2% ± 1.4%, P < .001), better baseline New York Heart Association class (P = .004), and fewer comorbidities than older patients. At 5 years mortality was lower among younger than older patients (5.3% vs 14.0%, P < .001) and no cases of structural valve deterioration occurred in either group. Effective orifice area was similar between age groups (P = .11), and mean gradient was 13.9 ± 5.4 vs 12.0 ± 4.1 mm Hg (P < .001). Multivariable linear regression identified several parameters associated with mean aortic gradient at 5 years, including baseline age and mean aortic gradient, discharge stroke volume index and EOA, and implanted valve size. Ninety-five percent of patients were in New York Heart Association class I/II through 5 years in both age groups (P = .85). CONCLUSIONS: Findings from this analysis demonstrate satisfactory safety, hemodynamic performance, and durability of the Avalus bioprosthesis through a 5-year follow-up in patients aged ≤ 65 and >65 years.

The robustness of the flow-gradient classification of severe aortic stenosis.

Objectives: A flow-gradient classification is used to determine the indication for intervention for patients with severe aortic stenosis (AS) with discordant echocardiographic parameters. We investigated the agreement in flow-gradient classification by stroke volume (SV) measurement at the left ventricular outflow tract (LVOT) and at the left ventricle. Methods: Data were used from a prospective cohort study and patients with severe AS (aortic valve area index ≤0.6 cm2/m2) with preserved ejection fraction (>50%) were selected. SV was determined by an echocardiographic core laboratory at the LVOT and by subtracting the 2-dimensional left ventricle end-systolic from the end-diastolic volume (volumetric). Patients were stratified into 4 groups based on SV index (35 mL/m2) and mean gradient (40 mm Hg). The group composition was compared and the agreement between the SV measurements was investigated using regression, correlation, and limits of agreement. In addition, a systematic LVOT diameter overestimation of 1 mm was simulated to study flow-gradient reclassification. Results: Of 1118 patients, 699 were eligible. The group composition changed considerably as agreement on flow state occurred in only 50% of the measurements. LVOT SV was on average 15.1 mL (95% limits of agreement -24.9:55.1 mL) greater than volumetric SV. When a systematic 1-mm LVOT diameter overestimation was introduced, the low-flow groups halved. Conclusions: There was poor agreement in the flow-gradient classification of severe AS as a result of large differences between LVOT and volumetric SV. Furthermore, this classification was sensitive to small measurement errors. These results stress that parameters beyond the flow-gradient classification should be considered to ensure accurate recommendations for intervention.

Surgical aortic valve replacement with a stented pericardial bioprosthesis: 5-year outcomes.

OBJECTIVES: This analysis evaluated the safety, durability and haemodynamic performance of a stented bovine pericardial valve through 5 years of follow-up in patients with an indication for surgical aortic valve replacement. METHODS: Kaplan-Meier analysis was used to estimate the incidence of survival and valve-related thromboembolism, major paravalvular leak, endocarditis, structural valve deterioration (SVD) and reintervention. The mean aortic gradient and New York Heart Association (NYHA) functional class were also evaluated. RESULTS: A total of 1118 patients have received the Avalus valve; 564 have completed the 5-year follow-up. The median follow-up was 4.85 years (4810 patient-years total follow-up). At baseline, the mean age was 70.2 ± 9.0 years; 75.1% of patients were male. The Society of Thoracic Surgeons predicted risk of mortality was 2.0 ± 1.4%. Most patients were in NYHA functional class II (46.8%) or III (40.3%). At the 5-year follow-up, the overall Kaplan-Meier survival rate was 88.1% (85.9-90.0%). The Kaplan-Meier event rates were 5.6% (4.3-7.2%) for thromboembolism, 4.4% (3.2-6.0%) for endocarditis, 0.2% (0.0-0.7%) for a major paravalvular leak and 3.2% (2.3-4.6%) for reintervention. There were no cases of SVD. The mean gradient decreased from 42.1 ± 17.1 mmHg at baseline, to 13.1 ± 4.7 mmHg at discharge and remained stable at 12.5 ± 4.6 mmHg at 5 years. More than 95% of patients were in NYHA functional class I/II 5 years after surgery. CONCLUSIONS: The findings of a high survival rate, excellent safety, no SVD and stable haemodynamic performance and functional status through 5 years of follow-up are encouraging. Additional follow-up is needed to assess the long-term durability of this contemporary surgical bioprosthesis.

Antithrombotic therapy and bleeding events after aortic valve replacement with a novel bioprosthesis.

OBJECTIVE: Several recent-generation surgical tissue valves have been found to have bleeding rates exceeding rates recommended by regulatory bodies. We explored bleeding events using data from the Pericardial Surgical Aortic Valve Replacement (PERIGON) Pivotal Trial for the Avalus valve (Medtronic, Minneapolis, Minn) to examine whether this end point remains relevant for the evaluation of bioprostheses. METHODS: Patients (n = 1115) underwent aortic valve replacement. Bleeding and thromboembolic event episodes in patients within 3 years postimplant were analyzed for frequency, timing, and severity, focusing on patients taking antiplatelet/anticoagulant medications at the time of the event. Clinical and hemodynamic outcomes are also reported. RESULTS: At 3 years, the Kaplan-Meier cumulative probability estimate of all-cause death was 7.2% (cardiac, 3.6%; valve-related, 1.1%). The Kaplan-Meier cumulative probability estimates of all and major hemorrhage were 8.7% and 5.2%, respectively. Ninety-nine bleeding events occurred in 86 patients: most occurred >30 days postsurgery. Among the 51 late major bleeds, in 5 cases the patients were taking anticoagulant/antiplatelet medication for prophylaxis after surgical aortic valve replacement at the time of the event, whereas the remaining patients were taking medications for other reasons. Age (hazard ratio, 1.035; 95% confidence interval, 1.004-1.068), peripheral vascular disease (hazard ratio, 2.135; 95% confidence interval, 1.106-4.122), renal dysfunction (hazard ratio, 1.920; 95% confidence interval, 1.055-3.494), and antithrombotic medication use at the time of the event (hazard ratio, 1.417; 95% confidence interval, 1.048-1.915) were associated with late bleeds (major and minor). CONCLUSIONS: Overall clinical outcomes demonstrated low mortality and few complications except for major bleeding. Most bleeding events occurred >30 days after surgery and in patients taking antiplatelet and/or anticoagulation for indications other than postimplant prophylaxis.

Minimally invasive triple valve surgery: A single center experience.

OBJECTIVE: Minimally invasive surgery is a widely accepted surgical treatment for valve disease, however triple valve surgery (TVS) is a complex and challenging procedure. The objective of this study was to describe the morbidity and mortality related to minimally invasive TVS at our institution. METHODS: This was a retrospective review of all minimally invasive TVS performed between 2012 and 2019. Baseline and perioperative characteristics were reviewed, as were postoperative outcomes. RESULTS: Eighteen patients underwent TVS; 12 patients underwent additional procedures at the time of TVS. Median time to initial extubation was 11.5 hours (interquartile range [IQR] 9.8-13.3). Intensive care unit and total length of stay were 1.22 (IQR, 1.16-1.31) and 9 (IQR, 6-17) days, respectively. No hospital deaths occurred; 30-, 90-, and 365-day mortality were 0%. Two postoperative neurologic complications occurred, two patients had acute kidney injuries. The most common complication was rhythm disturbance with five patients requiring permanent pacemaker implantation. Mean follow-up was 39.9 months (252-2642 days). CONCLUSIONS: Our findings demonstrate that minimally invasive TVS utilizing femoral cannulation results in an acceptable risk of complication. Short and intermediate term survival were excellent.

Retrospective Analysis of Thromboelastography-Directed Transfusion in Isolated CABG: Impact on Blood Product Use, Cost, and Outcomes.

Cardiac surgeries account for approximately 20% of blood use in the United States. Allogeneic transfusion has been associated with increased risk of morbidity and mortality, further justifying the need to reduce blood use. This study aimed at determining whether a point-of-care coagulation test, thromboelastography (TEG), impacted blood product administration and outcomes. Patients undergoing isolated coronary artery bypass grafting (CABG) were retrospectively reviewed before the use of TEG (2008-2009) (n = 640) and after implementation (2011-2012) (n = 458). Blood product use was compared between time frames. Logistic regression and generalized linear models were created to estimate the impact on outcomes including the reoperation rate, mortality, and cost. The mean use of each blood product was significantly reduced in the perioperative period. Overall blood product use was decreased by over 40%. Mediastinal re-exploration of bleeding was significantly reduced with TEG (4.8 vs. 1.5%). Six-month mortality was not impacted in this cohort nor was the readmission rate or hospital length of stay. However, blood cost and patient charges were significantly lower after TEG was introduced. The use of TEG to guide the administration of blood products during isolated CABG significantly affected the amounts and types of products given intra- and perioperatively. This resulted in less chest tube drainage, fewer returns to the operating room, and more accurate diagnosis of coagulopathic status. Cost savings to the patient and institution were appreciated as a consequence of these improved clinical outcomes.

Sizing Strategy and Implant Considerations for the Avalus Valve.

Hemodynamic performance of the Avalus valve through 3 years after implant is comparable to that of contemporary surgical bioprostheses. Many variables affect hemodynamic outcomes, including surgical technique. This article describes our experience with the Avalus bioprosthesis and strategies to achieve optimal hemodynamic performance.

The fallacy of indexed effective orifice area charts to predict prosthesis-patient mismatch after prosthesis implantation.

AIMS: Indexed effective orifice area (EOAi) charts are used to determine the likelihood of prosthesis-patient mismatch (PPM) after aortic valve replacement (AVR). The aim of this study is to validate whether these EOAi charts, based on echocardiographic normal reference values, can accurately predict PPM. METHODS AND RESULTS: In the PERIcardial SurGical AOrtic Valve ReplacemeNt (PERIGON) Pivotal Trial, 986 patients with aortic valve stenosis/regurgitation underwent AVR with an Avalus valve. Patients were randomly split (50:50) into training and test sets. The mean measured EOAs for each valve size from the training set were used to create an Avalus EOAi chart. This chart was subsequently used to predict PPM in the test set and measures of diagnostic accuracy (sensitivity, specificity, and negative and positive predictive value) were assessed. PPM was defined by an EOAi ≤0.85 cm2/m2, and severe PPM was defined as EOAi ≤0.65 cm2/m2. The reference values obtained from the training set ranged from 1.27 cm2 for size 19 mm up to 1.81 cm2 for size 27 mm. The test set had an incidence of 66% of PPM and 24% of severe PPM. The EOAi chart inaccurately predicted PPM in 30% of patients and severe PPM in 22% of patients. For the prediction of PPM, the sensitivity was 87% and the specificity 37%. For the prediction of severe PPM, the sensitivity was 13% and the specificity 98%. CONCLUSION: The use of echocardiographic normal reference values for EOAi charts to predict PPM is unreliable due to the large proportion of misclassifications.

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.

An in vitro comparison of internally versus externally mounted leaflets in surgical aortic bioprostheses.

OBJECTIVES: To improve haemodynamic performance, design modifications of prosthetic valves have been proposed with each new generation of valves. These different designs also impact the amount of mechanical wear, because mechanical stresses are distributed differently. Because long-term evidence for new prosthetic valves is lacking, this in vitro study compared hydrodynamic performance and durability among 3 currently available bioprosthetic valves with internally (IMLV) or externally mounted leaflets (EMLV). METHODS: Prostheses of the internally mounted Medtronic Avalus and Carpentier-Edwards Perimount Magna Ease valves were compared to prostheses of the externally mounted Abbott Trifecta valve. For each labelled size (e.g. 19, 21 and 23) of the 3 types, 3 valves underwent accelerated wear testing for up to 600 million cycles, corresponding to ∼15 years of simulated wear. The valves underwent hydrodynamic testing and visual inspection. RESULTS: EMLV had the largest effective orifice area and lowest pressure gradient for each labelled size at baseline and 600 million cycles; the effective orifice area and the pressure gradient were equivalent for the 2 types of IMLV. Five of 9 EMLVs had at least 1 hole or tear in the leaflet tissue around the stent posts, which resulted in severe regurgitation at 500 million cycles in 2 cases. All IMLVs were intact at 600 million cycles with minimal tissue wear. CONCLUSIONS: EMLV showed superior hydrodynamic performance but inferior mechanical durability compared to IMLV after 600 million cycles of testing. The primary failures were because of significant mechanical abrasion in the commissural region, which may warrant close monitoring of EMLV during long-term follow-up.

Prospective US investigational device exemption trial of a sutureless aortic bioprosthesis: One-year outcomes.

OBJECTIVES: We performed a prospective, single-arm clinical trial approved under a Food and Drug Administration Investigational Device Exemption to assess safety and efficacy of Perceval, a sutureless bovine pericardial aortic valve representing the initial US experience. METHODS: From June 2013 to January 2015, 300 patients (mean age 76.7 ± 7.7 years, 54.3% men, 37.3% ≥80 years, median Society of Thoracic Surgeons Predicted Risk of Mortality 2.8%), underwent Perceval valve implantation at 18 centers across the United States. Twenty patients (6.7%) had a bicuspid aortic valve and 5 (1.7%) patients had previous aortic valve replacement. A minimally invasive approach was used in 80 (26.7%) and concomitant procedures were performed in 113 (37.8%) patients. RESULTS: Two hundred eighty-nine patients (96.3%) were successfully implanted. Operative mortality (≤30 days) was 1.3% (n = 4) (observed to expected ratio of 0.40). One-year results included all-cause mortality in 5.2% (n = 15), stroke in 1% (n = 3), and endocarditis in 1.7% (n = 5). New permanent periprocedural pacemaker rate was 10.7% (n = 30/281); 2.5% (n = 7/281) resulted from third-degree atrioventricular block. One-year valve-related reoperation was 2.1% (n = 6). At 1-year follow-up, 98% of patients were in New York Heart Association class I/II, left ventricular mass index decreased from 103.5 ± 30.1 g/m2 at discharge to 95.8 ± 27.1 g/m2 (P = .001), and 3 (1.3%) moderate paravalvular leaks were identified. Health-related quality of life score increased from 62.7 ± 21.8 before surgery to 85.5 ± 17.8 at 1 year (P < .001). CONCLUSIONS: These results confirm the safety and effectiveness of the Perceval sutureless aortic valve replacement in study patients with lower mortality than expected from a risk prediction model. Persistent hemodynamic benefit and improvement in quality of life at 1 year support the importance of this device in the management of aortic valve disease.

Minimally Invasive Mitral Valve Surgery II: Surgical Technique and Postoperative Management.

Techniques for minimally invasive mitral valve repair and replacement continue to evolve. This expert opinion, the second of a 3-part series, outlines current best practices for nonrobotic, minimally invasive mitral valve procedures, and for postoperative care after minimally invasive mitral valve surgery.

Minimally Invasive Valve Surgery

Atividade de educação médica continuada onde Joseph Lamelas (moderador) e Michael G. Moront (palestrante) discorrem sobre cirurgia minimamente invasiva das válvulas cardíacas. Há a possibilidade de assistir ao vídeo, ler a transcrição das falas com slides e fazer o download do material em formato ppt. Também traz a possibilidade de realizar o teste de educação médica continuada da atividade e informação de como obter créditos pela mesma. Necessário estar cadastrado no site www.theheart.org para acesso ao material.