Current definitions of hemodynamic structural valve deterioration after bioprosthetic aortic valve replacement lack consistency.

Objective: New echocardiographic definitions have been proposed for hemodynamic structural valve deterioration. We aimed to study their consistency in classifying structural valve deterioration after surgical aortic valve replacement. Methods: Data were used of patients undergoing surgical aortic valve replacement in a multicenter, prospective cohort study with a 5-year follow-up. All patients received the same stented bioprosthesis. Echocardiographic parameters were assessed by an independent core laboratory. Moderate or greater stenotic hemodynamic structural valve deterioration was defined according to Capodanno and colleagues, Dvir and colleagues, and the Valve Academic Research Consortium 3; regurgitation data were not considered in this analysis. Consistency was quantified on the basis of structural valve deterioration classification at subsequent time points. Results: A total of 1118 patients received implants. Patients' mean age was 70 years, and 75% were male. Hemodynamic structural valve deterioration at any visit was present in 51 patients (4.6%), 32 patients (2.9%), and 34 patients (3.0%) according to Capodanno, Dvir, and Valve Academic Research Consortium 3. A total of 1064 patients (95%) were never labeled with structural valve deterioration by any definition. After the first classification with structural valve deterioration, 59%, 59%, and 65% had no subsequent structural valve deterioration classification according to Capodanno, Dvir, and Valve Academic Research Consortium 3, respectively. Conclusions: The current definitions of hemodynamic structural valve deterioration are strong negative predictors but inconsistent positive discriminators for the detection of stenotic hemodynamic structural valve deterioration. Although the diagnosis of structural valve deterioration may be categorical, echocardiographic indices lack this degree of precision in the first 5 years after surgical aortic valve replacement. The inconsistency of current structural valve deterioration definitions impedes the detection of true valve degeneration, which challenges the clinical usefulness of these definitions.

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.

Safety, effectiveness and haemodynamic performance of a new stented aortic valve bioprosthesis.

OBJECTIVES: We assessed the safety, effectiveness and haemodynamic performance of a new bovine stented aortic valve bioprosthesis (Avalus™). METHODS: The PERIGON Pivotal Trial is a prospective, non-randomized, multicentre study. Subjects had symptomatic moderate or severe aortic stenosis or chronic, severe aortic regurgitation. Death, valve-related adverse events (AEs), functional recovery and haemodynamic performance were assessed at discharge, 3-6 months and 1 year. The primary analysis compared 'late' (>30 days post-implant) linearized rates of valve-related thromboembolism, thrombosis, all and major haemorrhage, all and major paravalvular leak (PVL) and endocarditis after implantation with objective performance criteria (OPC) for AEs, in accordance with EN ISO 5840:2009. We hypothesized that the upper 95% confidence bounds of the true linearized AE rates would be ≥ 2 × OPC; rejection of the null hypothesis would demonstrate that these rates were below acceptable rates. The analysis was required to include at least 150 patients followed to 1 year and 400 valve-years. Kaplan-Meier survival analysis was also performed. RESULTS: Total number of valve-years was 459.5 (n = 686). Linearized rates were <2 × OPC for death and valve-related thromboembolism, valve thrombosis, all and major PVL, and endocarditis, but ≥2 × OPC for all and major haemorrhage. Survival at 1 year (n = 270) was 96.4%. Patients showed good functional recovery, and haemodynamic performance was within expected range. CONCLUSIONS: This analysis demonstrated a good safety profile and clinical effectiveness of the Avalus valve except for bleeding rates. The linearized rates of all and major haemorrhage may be related to long-term anticoagulation for non-valvular indications and the length of follow-up of this cohort. TRIAL REGISTRATION: NCT02088554 (www.clinicaltrials.gov).