High-gradient Aortic Stenosis Research Articles

Prevalence and Outcomes of Patients With Discordant High-Gradient Aortic Stenosis

BackgroundConflicting prognostic results have been reported in patients with discordant high-gradient aortic stenosis ([DHG-AS] the combination of a mean pressure gradient ≥40 mm Hg and an aortic valve area [AVA] >1 cm2). Moreover, existing studies only included selected patients without concomitant aortic regurgitation. ObjectivesThe authors assessed the prevalence and survival of patients presenting with DHG-AS in an unselected group of consecutive patients presenting to the echocardiography laboratory of a tertiary referral center. MethodsA total of 3,547 adult patients with AVA ≤1.5 cm2 and peak aortic jet velocity ≥2.5 m/s or mean gradient ≥25 mm Hg who presented between 2005 and 2015 were included. Baseline clinical and echocardiographic data, and, when available, aortic valve calcium (AVC) score were collected in an institutional database, with subsequent retrospective analysis. The primary endpoint was all-cause mortality during follow-up. ResultsDHG-AS was observed in 163 patients (11.6% of patients with a high gradient). After adjustment for potential confounders, overall mortality rate of patients with DHG-AS was similar to that of patients with concordant severe aortic stenosis (HR: 0.98 [95% CI: 0.66-1.44]; P = 0.91), and patients with discordant low-gradient aortic stenosis (HR: 0.85 [95% CI: 0.58-1.26]; P = 0.42), and higher than concordant moderate aortic stenosis (HR: 0.54 [95% CI: 0.36-0.81]; P = 0.003). After adjustment for aortic velocities, aortic regurgitation had no significant impact on survival. AVC was higher than in patients with concordant moderate aortic stenosis and discordant low-gradient aortic stenosis, and not significantly different from that of concordant severe aortic stenosis. ConclusionsDHG-AS is not uncommon. Whereas AVA >1.0 cm2 is often seen as moderate aortic stenosis, a high-pressure gradient conveys a poor prognosis, whatever the AVA and the severity of concomitant aortic regurgitation.

Myocardial sodium-glucose cotransporter 2 expression and cardiac remodelling in patients with severe aortic stenosis: The BIO-AS study.

Cardiac remodelling plays a major role in the prognosis of patients with aortic stenosis (AS) and could impact the benefits of aortic valve replacement. Our study aimed to evaluate the expression of sodium-glucose cotransporter 2 (SGLT2) gene and protein in patients with severe AS stratified in high gradient (HG) and low flow-low gradient (LF-LG) AS and its association with cardiac functional impairments. Gene expression and protein levels of main biomarkers of cardiac fibrosis (galectin-3, sST2, serpin-4, procollagen type I amino-terminal peptide, procollagen type I carboxy-terminal propeptide, collagen, transforming growth factor [TGF]-β), inflammation (growth differentiation factor-15, interleukin-6, nuclear factor-κB [NF-κB]), oxidative stress (superoxide dismutase 1 [SOD1] and 2 [SOD2]), and cardiac metabolism (sodium-hydrogen exchanger, peroxisome proliferator-activated receptor [PPAR]-α, PPAR-γ, glucose transporter 1 [GLUT1] and 4 [GLUT4]) were evaluated in blood samples and heart biopsies of 45 patients with AS. Our study showed SGLT2 gene and protein hyper-expression in patients with LF-LG AS, compared to controls and HG AS (p < 0.05). These differences remained significant even after adjusting for age, gender, body mass index, history of diabetes mellitus, arterial hypertension, and coronary artery disease. SGLT2 gene expression was positively correlated with: (i) TGF-β (r = 0.72, p < 0.001) and collagen (r = 0.73, p < 0.001) as markers of fibrosis; (ii) NF-κB (r = 0.36, p < 0.01) and myocardial interleukin-6 (r = 0.68, p < 0.001) as markers of inflammation: (iii) SOD2 (r = -0.38, p < 0.006) as a marker of oxidative stress; (iv) GLUT4 (r = 0.33, p < 0.02) and PPAR-α (r = 0.36, p < 0.01) as markers of cardiac metabolism. In patients with LF-LG AS, SGLT2 gene and protein were hyper-expressed in cardiomyocytes and associated with myocardial fibrosis, inflammation, and oxidative stress.

Surgical aortic valve replacement etiologies, hemodynamics, and outcomes in 1346 patients from the Malaysian heart centre

BackgroundThis study examined the characteristics and outcomes of surgical aortic valve replacement (SAVR) both isolated and in combination with other cardiac surgery in Malaysia from 2015 to 2021.MethodsThis was a retrospective study of 1346 patients analyzed on the basis of medical records, echocardiograms and surgical reports. The overall sample was both considered as a whole and divided into aortic stenosis (AS)/aortic regurgitation (AR)-predominant and similar-severity subgroups.ResultsThe most common diagnosis was severe AS (34.6%), with the 3 most common etiologies being bicuspid valve degeneration (45.3%), trileaflet valve degeneration (36.3%) and rheumatic valve disease (12.2%). The second most common diagnosis was severe AR (25.5%), with the most common etiologies being root dilatation (21.0%), infective endocarditis (IE) (16.6%) and fused prolapse (12.2%). Rheumatic valve disease was the most common mixed disease. A total of 54.5% had AS-predominant pathology (3 most common etiologies: bicuspid valve degeneration valve, degenerative trileaflet valve and rheumatic valve disease), 36.9% had AR-predominant pathology (top etiologies: root dilatation, rheumatic valve disease and IE), and 8.6% had similar severity of AS and AR. Overall, 62.9% of patients had trileaflet valve morphology, 33.3% bicuspid, 0.6% unicuspid and 0.3% quadricuspid. For AS, the majority were high-gradient severe AS (49.9%), followed by normal-flow low-gradient (LG) severe AS (10.0%), paradoxical low-flow (LF)-LG severe AS (6.4%) and classical LF-LG severe AS (6.1%). The overall in-hospital and total 1-year mortality rates were 6.4% and 14.8%, respectively. Pure severe AS had the highest mortality. For AS-predominant pathology, the etiology with the highest mortality was trileaflet valve degeneration; for AR-predominant pathology, it was dissection. The overall survival probability at 5 years was 79.5% in all patients, 75.7% in the AS-predominant subgroup, 83.3% in the AR-predominant subgroup, and 87.3% in the similar-severity subgroup.ConclusionsThe 3 most common causes of AS- predominant patients undergoing SAVR is bicuspid valve degeneration, degenerative trileaflet valve and rheumatic and for AR-predominant is root dilatation, rheumatic and IE. Rheumatic valve disease is an important etiology in our SAVR patients especially in mixed aortic valve disease.Study registration IJNREC/562/2022.

Prognostic impact of cardiac damage staging classification in each aortic stenosis subtype undergoing TAVI.

The prognostic value of cardiac damage staging classifications across the haemodynamic spectrum of severe aortic stenosis (AS) remains unknown. We aimed to investigate the prognostic impact of cardiac damage staging classifications in patients with high-gradient AS (HG-AS) and low-gradient AS (LG-AS) undergoing transcatheter aortic valve implantation (TAVI). In a prospective TAVI registry, five-year mortality was evaluated for early stages of cardiac damage (stage 0, 1, or 2) and advanced stages of cardiac damage (stage 3 or 4) in patients with HG-AS, classical low-flow (LF) LG-AS, LF LG-AS with preserved ejection fraction (pEF), and normal-flow (NF) LG-AS. Among 2,090 patients undergoing TAVI, 1,045 patients had HG-AS, 337 patients had classical LF LG-AS, 394 patients had LF LG-AS with pEF, and 314 patients had NF LG-AS. The majority of patients with classical LF LG-AS exhibited advanced cardiac damage (73.6%), followed by LF LG-AS with pEF (55.6%), NF LG-AS (51.6%), and HG-AS (50.6%). Patients with advanced stage cardiac damage had significantly higher mortality after TAVI than those with early stage cardiac damage in all subtypes of AS (adjusted hazard ratio [HRadjusted] 1.66, 95% confidence interval [CI]: 1.34-2.06 for HG-AS; HRadjusted 1.49, 95% CI: 1.02-2.16 for classical LF LG-AS; HRadjusted 1.69, 95% CI: 1.22-2.35 for LF LG-AS with pEF; and HRadjusted 1.52, 95% CI: 1.04-2.32 for NF LG-AS). Cardiac damage staging classifications stratified mortality after TAVI irrespective of AS subtype.

Aortic stenosis and right ventricular dysfunction

At the present time, right ventricular function in patients with aortic stenosis is insufficiently taken into account in the decision-making process of aortic valve replacement. The aim of our study was to evaluate significance of right ventricular dysfunction in patients with severe aortic stenosis by modern 3D echocardiographic methods. This is prospective analysis of 68 patients with severe high and low-gradient aortic stenosis. We evaluated function of left and right ventricle on the basis of 3D reconstruction. Enddiastolic, endsystolic volumes, ejection fraction and stroke volumes of both chambers were assessed. There were more patients with right ventricular dysfunction in low-gradient group (RVEF < 45%) than in the high-gradient group (63.6% vs 39%, p = 0.02). Low-gradient patients had worse right ventricular function than high-gradient patients (RVEF 36% vs 46%, p = 0.02). There wasn’t any significant correlation between the right ventricular dysfunction and pulmonary hypertension (r = − 0.25, p = 0.036). There was significant correlation between left and right ejection fraction (r = 0.78, p < 0.0001). Multiple regression analysis revealed that the only predictor of right ventricular function is the left ventricular function. According to our results we can state that right ventricular dysfunction is more common in patients with low-gradient than in high-gradient aortic stenosis and the only predictor of right ventricular dysfunction is left ventricular dysfunction, probably based on ventriculo-ventricular interaction. Pulmonary hypertension in patients with severe AS does not predict right ventricular dysfunction.

Impact of cardiac staging classification in transcatheter aortic valve implantation for major subtypes of severe aortic stenosis

Abstract Background Staging classification to quantify the extent of extra-aortic valve cardiac damage is recognized as a useful prognostic tool in patients undergoing transcatheter aortic implantation (TAVI) for aortic stenosis (AS). However, this classification has not been validated in each AS subtype. Objectives The present study aimed to investigate the prognostic impact of staging classification in patients with four major AS subtypes. Methods In a prospective TAVI registry, patients were classified into high gradient AS (HG-AS), classical low flow low gradient AS (LFLG-AS), paradoxical LFLG-AS, and normal flow low gradient AS (NFLG-AS). Five-year mortality was compared between early stage (stage 0, 1, or 2) and advanced stage (stage 3 or 4). Results Among 1,507 patients undergoing TAVI, 812 patients had HG-AS, 186 patients had classical LFLG-AS, 277 patients had paradoxical LFLG-AS, and 232 patients had NFLG-AS. There were much difference in the distribution of cardiac stage among AS subtypes; advanced stage accounting for 54.3% in HG-AS, 58.6% in NFLG-AS, 62.5% in paradoxical LFLG-AS, and 80.6% in classical LFLG-AS. Patients with advanced stage had higher all-cause mortality compared with early stage in HG-AS and paradoxical LFLG-AS (HRadjusted 2.00; 95% CI 1.44-2.78 and HRadjusted 2.15; 95% CI 1.43-3.21), but not in classical LFLG-AS and NFLG-AS (HRadjusted 1.17; 95% CI 0.70-1.95 and HRadjusted 1.43; 95% CI 0.90-2.27). Conclusions Early stage was associated with a reduced risk for five-year mortality in patients with HG-AS and paradoxical LFLG-AS, while there was comparable mortality between early and advanced stages in patients with classical LFLG-AS and NFLG-AS.

Impact of route of access and stenosis subtype on outcome after transcatheter aortic valve replacement.

Previous analyses have reported the outcomes of transcatheter aortic valve replacement (TAVR) for patients with low-flow, low-gradient (LFLG) aortic stenosis (AS), without stratifying according to the route of access. Differences in mortality rates among access routes have been established for high-gradient (HG) patients and hypothesized to be even more pronounced in LFLG AS patients. This study aims to compare the outcomes of patients with LFLG or HG AS following transfemoral (TF) or transapical (TA) TAVR. A total of 910 patients, who underwent either TF or TA TAVR with a median follow-up of 2.22 (IQR: 1.22-4.03) years, were included in this multicenter cohort study. In total, 146 patients (16.04%) suffered from LFLG AS. The patients with HG and LFLG AS were stratified according to the route of access and compared statistically. The operative mortality rates of patients with HG and LFLG were found to be comparable following TF access. The operative mortality rate was significantly increased for patients who underwent TA access [odds ratio (OR): 2.91 (1.54-5.48), p = 0.001] and patients with LFLG AS [OR: 2.27 (1.13-4.56), p = 0.02], which could be corroborated in a propensity score-matched subanalysis. The observed increase in the risk of operative mortality demonstrated an additive effect [OR for TA LFLG: 5.45 (2.35-12.62), p < 0.001]. LFLG patients who underwent TA access had significantly higher operative mortality rates (17.78%) compared with TF LFLG (3.96%, p = 0.016) and TA HG patients (6.36%, p = 0.024). HG patients experienced a twofold increase in operative mortality rates following TA compared with TF access, while LFLG patients had a fivefold increase in operative mortality rates. TA TAVR appears suboptimal for patients with LFLG AS. Prospective studies should be conducted to evaluate alternative options in cases where TF is not possible.

Serial global and longitudinal RV functional assessment in symptomatic, severe aortic stenosis undergoing AVR

Abstract Background Right ventricular (RV) dysfunction is currently regarded as an end-stage marker of of cardiac damage in patients with severe aortic stenosis (AS). However, global RV assessment prior to and after aortic valve replacement (AVR) has largely been neglected and little is known about RV response after AVR. Aims to describe the prevalence of RV dysfunction in a group of patients with severe AS referred to surgical AVR, and to evaluate post-operative evolution, as assessed by both CMR and echocardiography. Methodology Single-center prospective cohort study of patients with isolated severe symptomatic high-gradient AS submitted to surgical AVR. Those with previous known cardiomyopathy were excluded. All patients performed same day transthoracic echocardiogram (TTE) and CMR both before surgery and at the 3rd to 6th post-operative month. Global RV dysfunction was defined by an RVEF &amp;lt;45% at CMR. Echocardiographic evidence of RV dysfunction was defined by: tricuspid annular plane excursion (TAPSE) &amp;lt;17mm, free wall longitudinal strain (FWLS) &amp;gt;- 21% or RV S’ wave by tissue Doppler imaging &amp;lt;12 cm/s. Results A total of 112 patients were included (mean age 71 ± 8 years; mean valvular transaortic gradient 61 ± 18 mmHg; mean indexed aortic valve area 0.4 ± 0.1 cm2/m2; mean indexed systolic volume 48 ± 11mL/m2,mean LV ejection fraction by CMR pre and post-AVR: 60 ± 10% and 59 ± 8%; mean pulmonary artery systolic pressure pre-AVR: 35 ± 10mmHg). Only four of the patients (3.4%) had pre-operative stage 4 cardiac damage (RV dysfunction) as assessed by CMR. Moreover, only FWLS at TTE was significantly related to CMR RVEF at both pre-operative (Spearmen R= -0.337, p&amp;lt;0.001) and post-operative evaluation (Spearmen R = -0.217, p=0.026). Contrary to CMR RVEF (58 ± 15% vs. 57 ± 8%, p=0.461), there was a significant worsening of all TTE parameters at post-operative evaluation – overall, 32%, 20% and 25% of patients met one, two or three echocardiographic parameters of RV dysfunction - Figure 1. Conclusion RV dysfunction is common after AVR is patients with severe AS as assessed by common TTE parameters, but this is not accompanied by significant impairment of RVEF. Overall, only FWLS showed a consistent, albeit only moderate, correlation with RVEF at pre and post-AVR. These results highlight the limitations of longitudinal function indexes in evaluating post-surgical global RV function.

Prognostic impact of atrial fibrillation in patients with paradoxical low-flow low-gradient aortic stenosis undergoing TAVI

Abstract Background Atrial fibrillation (AF) has been associated with adverse clinical outcomes after transcatheter aortic valve implantation (TAVI). However, the impact of AF on post-TAVI flow status and clinical outcomes in patients with paradoxical low-flow low-gradient aortic stenosis (PLFLG-AS) is still unclear. Objectives The present study aimed to investigate the effect of AF on post-TAVI flow status and clinical outcomes in patients with PLFLG-AS undergoing TAVI. Methods In a prospective TAVI registry, patients with preserved left ventricular ejection fraction (LVEF ≥50%) were stratified according to the flow-gradient status and presence of AF. Results Among 2,259 TAVI patients with preserved LVEF between August 2007 and June 2021, 765 had high-gradient AS (HG-AS) (mean gradient ≥40 mmHg) and 444 had PLFLG-AS (mean gradient &amp;lt;40 mmHg and stroke volume index [SVi] &amp;lt;35 ml/m2). AF was observed in 199 patients with HG-AS (26.0%) and 190 patients with PLFLG-AS (42.8%). At 1 year after TAVI, SVi was significantly improved in PLFLG-AS patients with no AF, whereas those with AF remained low-flow status (from 25.9 ± 8.5 mL/m2 to 37.2 ± 9.9 mL/m2 and from 26.8 ± 5.1 mL/m2 to 26.1 ± 9.1 mL/m2, respectively). PLFLG-AS patients had an increased risk of all-cause mortality at 1 year after TAVI compared with those without AF (HRadjust 2.79; 95% CI 1.58-4.93). Whereas PLFLG-AS patients with no AF had a similar mortality compared with HG-AS patients with no AF (HRadjust 0.84; 95% CI 0.49-1.44). Conclusions AF was associated with worse flow status and impaired prognosis after TAVI in patients with PLFLG-AS.

Abstract 12696: Association Between Aortic Valve Calcification and Aortic Valve Size in Patients With Severe High Gradient Aortic Stenosis

Introduction: It is known that women require less aortic valve calcification (AVC) to develop severe aortic stenosis (AS) than men. Thus, gender specific AVC thresholds for the diagnosis of severe AS are recommended by the ACC/AHA guidelines. However, it is also known that women have smaller hearts and aortic valves (AV) than men. Hypothesis: We hypothesize that AVC is associated with AV size independently from sex. Methods: Consecutive patients with severe high gradient AS who underwent cardiac computed tomography (CT) were included in our study. AV annulus area and AVC assessed with the Agatston score were measured in CT. Linear regression model adjusted for age and sex as well as spearman correlation analysis were performed. Results: 437 patients with severe high gradient AS (mean age 80±6 years, 47% female) were included. Significant differences in AVC (3363 [2582-4398] AU vs. 1984 [1354-2856] AU, p&lt;0.001) and AV annulus area (509 ± 75 mm 2 vs. 408 ± 67 mm 2 , p&lt;0.001) between men and women were found. We observed a significant correlation of AV annulus area with AVC (r=0.6, p&lt;0.001). On multivariate regression AV annulus area was significantly associated with the Agatston score (β=7.5, p&lt;0.001). Furthermore, separate regression analyses for men and women confirmed the significant association of AV annulus area with AVC independent from sex (β (men) =7.0, p&lt;0.001; β (women) =8.2, p&lt;0.001). Conclusions: In patients with severe high gradient AS AV annulus area is associated with AVC independent from sex. Thus, an indexation of AVC thresholds to AV size should be applied rather than using fixed sex-dependent AVC cut-offs for the definition of severe AS.

Quality of Life After Transcatheter Aortic Valve Replacement in Normal-Flow, Low-Gradient Aortic Stenosis

BackgroundPrior studies of aortic valve replacement (AVR) in patients with normal-flow, low-gradient aortic stenosis (NF-LG AS) have demonstrated conflicting results regarding the survival benefit of AVR. Changes in quality of life (QoL) after transcatheter AVR (TAVR) have not been reported in this population. ObjectivesThe purpose of this study was to compare changes in QoL after TAVR for patients with NF-LG AS to patients with high-gradient aortic stenosis (HG-AS). MethodsPatients who underwent TAVR for severe aortic stenosis (AS) were divided into 4 hemodynamic profiles of AS, including NF-LG AS. Changes in Kansas City Cardiomyopathy Questionnaire-12 score from baseline to 1 year were compared between AS groups. The primary composite outcome indicating clinical improvement consisted of survival to 1 year and improved Kansas City Cardiomyopathy Questionnaire overall summary score of ≥5 points while adjusting for relevant baseline factors. ResultsOut of 860 patients who underwent TAVR, high gradient AS was present in 368 (42.8%) patients and NF-LG AS in 245 (28.5%). HG-AS and NF-LG AS groups had a similar proportion of patients who met the primary unadjusted outcome of clinical improvement (70.4% vs 63.9%, respectively; P = 0.189). One-year Kaplan-Meier mortality estimates were higher for NF-LG AS patients than HG-AS patients (12.9% vs 5.8%, P < 0.001). In the primary adjusted analysis, there was no significant difference in the composite outcome between HG and NF-LG AS groups (adjusted OR: 0.72, 95% CI: 0.47-1.11). ConclusionsSelected patients with NF-LG AS experienced similar improvement in QoL after TAVR compared with HG-AS. Further investigation of patients with NF-LG AS will help to inform optimal selection for treatment with TAVR.

Haemodynamic and metabolic phenotyping of patients with aortic stenosis and preserved ejection fraction: A specific phenotype of heart failure with preserved ejection fraction?

Degenerative aortic valve stenosis with preserved ejection fraction (ASpEF) and heart failure with preserved ejection fraction (HFpEF) display intriguing similarities. This study aimed to provide a non-invasive, comparative analysis of ASpEF versus HFpEF at rest and during exercise. We prospectively enrolled 148 patients with HFpEF and 150 patients with degenerative moderate-to-severe ASpEF, together with 66 age- and sex-matched healthy controls. All subjects received a comprehensive evaluation at rest and 351/364 (96%) performed a combined cardiopulmonary exercise stress echocardiography test. Patients with ASpEF eligible for transcatheter aortic valve replacement (n = 125) also performed cardiac computed tomography (CT). HFpEF and ASpEF patients showed similar demographic distribution and biohumoral profiles. Most patients with ASpEF (134/150, 89%) had severe high-gradient aortic stenosis; 6/150 (4%) had normal-flow, low-gradient ASpEF, while 10/150 (7%) had low-flow, low-gradient ASpEF. Both patient groups displayed significantly lower peak oxygen consumption (VO2 ), peak cardiac output, and peak arteriovenous oxygen difference compared to controls (all p < 0.01). ASpEF patients showed several extravalvular abnormalities at rest and during exercise, similar to HFpEF (all p < 0.01 vs. controls). Epicardial adipose tissue (EAT) thickness was significantly greater in ASpEF than HFpEF and was inversely correlated with peak VO2 in all groups. In ASpEF, EAT was directly related to echocardiography-derived disease severity and CT-derived aortic valve calcium burden. Functional capacity is similarly impaired in ASpEF and HFpEF due to both peripheral and central components. Further investigation is warranted to determine whether extravalvular alterations may affect disease progression and prognosis in ASpEF even after valve intervention, which could support the concept of ASpEF as a specific sub-phenotype of HFpEF.

Association of atrial fibrillation with survival in patients with low-flow low-gradient aortic stenosis with preserved ejection fraction undergoing TAVI.

There is limited evidence on the prognostic significance of atrial fibrillation (AF) in patients with low flow, low gradient aortic stenosis with preserved ejection fraction (LFLG-pEF AS). We aimed to evaluate the recovery of stroke volume after transcatheter aortic valve implantation (TAVI) and clinical outcomes in patients with LFLG-pEF AS stratified by presence or absence of AF. In a prospective TAVI registry, patients with preserved left ventricular ejection fraction (LVEF≥50%) were stratified according to flow-gradient status and presence of AF. Among 2259 TAVI patients with preserved LVEF between August 2007 and June 2021, 765 had high-gradient AS (HG AS) and 444 had LFLG-pEF AS. AF was observed in 199 patients with HG AS (26.0%) and 190 patients with LFLG-pEF AS (42.8%). At 1 year, SVi was significantly improved in LFLG-pEF AS patients without AF, while SVi remained low in patients with AF (from 25.9±8.5mL/m2 to 37.2±9.9mL/m2 and from 26.8±5.1mL/m2 to 26.1±9.1mL/m2, respectively). LFLG-pEF AS patients with AF had an increased risk of 1-year all-cause mortality compared with those without AF (HRadjusted 2.57; 95% CI 1.44-4.59). LFLG-pEF AS patients without AF had similar mortality compared with HG AS patients without AF (HRadjusted 0.85; 95% CI 0.49-1.46). Patients with LFLG-pEF AS and AF experienced no relevant recovery of stroke volume after TAVI, but a more than two-fold increased risk of death compared to patients with HG AS or LFLG-pEF AS without AF. Clinical Trial Registration: https://www.clinicaltrials.gov. NCT01368250.

Exploring the mechanisms responsible for reduced systolic function in high-gradient aortic stenosis

ObjectiveTo characterise the mechanics responsible for the reduced ejection fraction (rEF) in high-gradient severe aortic stenosis (AS).Methods21 patients with high-gradient severe AS (aortic valve area (AVA) <1.0 cm2 and mean...

Changes in echocardiographic parameters over time in paradoxical low-flow low-gradient aortic stenosis

Abstract Funding Acknowledgements Type of funding sources: None. Background Although paradoxical low-flow low-gradient (LFLG) aortic stenosis (AS) has been considered a more severe form of AS with a worse prognosis than high-gradient (HG) AS, data on the natural history of this entity are scant. Objectives To assess the progression of the disease and evolution of the main echocardiographic variables for quantifying AS in patients with severe LFLG AS compared to HG and normal-flow low-gradient (NFLG) AS. Methods A longitudinal, observational, multicenter study including consecutive asymptomatic patients with severe AS (AVA&amp;lt;1.0cm²) and normal LVEF (≥50%) was conducted. Patients were classified according to baseline echocardiography into one of three groups: HG (mean gradient≥40 mmHg), NFLG (mean gradient&amp;lt;40 mmHg, indexed systolic volume (SVi)&amp;gt;35ml/m²), or LFLG (mean gradient&amp;lt;40mmHg, SVi≤35ml/m²). AS progression was analyzed by comparing patients’ baseline measurements and their last follow-up measurements or those taken prior to aortic valve replacement (AVR). Results Of the 903 included patients, 401 (44.4%) were HG, 405 (44.9%) NFLG, and 97 (10.7%) LFLG. The median total follow-up time was 60.2 months (IQR 44.7–83.4). Progression of the mean gradient in a linear mixed regression model was greater in low-gradient groups: LFLG vs. HG (regression coefficient 0.124, p = 0.005) and NFLG vs. HG (regression coefficient 0.068, p = 0.018). No differences were observed between the LFLG and NFLG groups (regression coefficient 0.056, p = 0.195). However, aortic valve area (AVA) reduction was slower in the LFLG group compared to the NFLG (p&amp;lt;0.001). During follow-up, 19.1% (n=9) of LFLG patients evolved to having NFLG AS and 44.7% (n=21) to having HG AS. 58.0% of patients underwent AVR with HG AS (n=29). Conclusions LFLG AS shows an intermediate AVA and gradient progression compared to NFLG and HG AS. The majority of patients initially classified as having LFLG AS changed over time to having other severe forms of AS, and most of them received AVR with HG AS.

The diagnostic accuracy of aortic valve calcium score in patients with low gradient and high gradient aortic stenosis

Abstract Funding Acknowledgements Type of funding sources: None. Introduction The gold standard imaging modality for diagnosing aortic stenosis (AS) is echocardiography (echo); the definition of severe AS is based on the transvalvular mean gradient (AMG) (&amp;gt;40 mmHg) and aortic valve area (AVA) (&amp;lt;1 cm2). However, in around one quarter of the cases echo provides discordant findings (AVA&amp;lt;1 cm2, despite of an AMG &amp;lt;40 mmHg), complicating clinical decision making. Computed tomography aortic valve calcium scoring (CT-AVC) offers an alternative diagnostic method. In cases with discordant echo measurements current guidelines recommend CT-AVC to decide on severity. Purpose Our aim was to validate the sensitivity of the recommended calcium score (CAS) thresholds within our patient population, as well as to identify any factors associated with below cut-off CAS values despite confirmed severe AS (CAS false negativity). Methods Our retrospective study included 332 consecutive patients with severe AS (AVA ≤1 cm2), who underwent CT angiography (CTA) for transcatheter aortic valve implantation (TAVI) planning. Based on the AMG the patients were classified into high gradient (HG: AMG ≥ 40 mmHg) and low gradient (LG: AMG &amp;lt;40 mmHg) groups. In the LG group AS severity was assessed by a multiparametric algorithm. To specify the predictors of CAS false negativity among patients with HG-AS, logistic regression analysis was used. The patients were followed for 50 months. Cox proportional hazard model was used to assess the risk of death from any cause. Results The HG-AS group consisted of 244 and the LG-AS cohort of 88 patients. In the HG-AS population the sensitivity of CAS to diagnose severe AS was 89%. Within the HG severe AS group, logistic regression analysis revealed an association between CAS false negativity and the AMG (OR 0.89, CI 0.83 – 0.95, p &amp;lt;0,001), whereas none of the other tested factors (age, sex, hypertension, diabetes, left ventricle function, renal function) showed a predictive value. In the LG-AS group, contrary to the HG-AS patients, the sensitivity of CAS to define severe LG AS was limited (53% in males and 67% in females). Over a median follow-up of 50 months, the prognosis of HG AS patients with low CAS (false negative group) was more favourable than that of the high CAS patient population (HR 0.41; CI 017 – 097; p = 0.04). Conclusions Our results confirmed that among patients with HG AS, the recommended CAS thresholds provide a good diagnostic sensitivity for severe AS. Nonetheless, the number of severe AS patients with low CAS is not negligible, especially within the LG-AS population, where the diagnosis is the most challenging. Our findings underline that in patients with discordant echocardiographic findings, a personalized, multiparametric diagnostic approach is needed, instead basing the final diagnosis exclusively on CAS.

Clinical Outcomes in High-Gradient, Classical Low-Flow, Low-Gradient, and Paradoxical Low-Flow, Low-Gradient Aortic Stenosis After Transcatheter Aortic Valve Implantation: A Report From the SwissTAVI Registry.

Background In view of the rising global burden of severe symptomatic aortic stenosis, its early recognition and treatment is key. Although patients with classical low-flow, low-gradient (C-LFLG) aortic stenosis have higher rates of death after transcatheter aortic valve implantation (TAVI) when compared with patients with high-gradient (HG) aortic stenosis, there is conflicting evidence on the death rate in patients with severe paradoxical low-flow, low-gradient (P-LFLG) aortic stenosis. Therefore, we aimed to compare outcomes in real-world patients with severe HG, C-LFLG, and P-LFLG aortic stenosis undergoing TAVI. Methods and Results Clinical outcomes up to 5 years were addressed in the 3 groups of patients enrolled in the prospective, national, multicenter SwissTAVI registry. A total of 8914 patients undergoing TAVI at 15 heart valve centers in Switzerland were analyzed for the purpose of this study. We observed a significant difference in time to death at 1 year after TAVI, with the lowest observed in HG (8.8%) aortic stenosis, followed by P-LFLG (11.5%; hazard ratio [HR], 1.35 [95% CI, 1.16-1.56]; P<0.001) and C-LFLG (19.8%; HR, 1.93 [95% CI, 1.64-2.26]; P<0.001) aortic stenosis. Cardiovascular death showed similar differences between the groups. At 5 years, the all-cause death rate was 44.4% in HG, 52.1% in P-LFLG (HR, 1.35 [95% CI, 1.23-1.48]; P<0.001), and 62.8% in C-LFLG aortic stenosis (HR, 1.7 [95% CI, 1.54-1.88]; P<0.001). Conclusions Up to 5 years after TAVI, patients with P-LFLG have higher death rates than patients with HG aortic stenosis but lower death rates than patients with C-LFLG aortic stenosis.

Target Aortic Stenosis: A National Initiative to Improve Quality of Care and Outcomes for Patients With Aortic Stenosis.

Target Aortic Stenosis: A National Initiative to Improve Quality of Care and Outcomes for Patients With Aortic Stenosis.

P298 TRANS–AXILLARY ACCESS AS AN ALTERNATIVE ROUTE IN TRANSCATHETER AORTIC VALVE IMPLANTATION

Abstract Background Transcatheter aortic valve replacement (TAVR) is the main procedure for treating severe aortic stenosis in patients considered at high surgical risk. Generally, this procedure is performed through percutaneous femoral arterial access. The presence of anatomical variants or peripheral atherosclerotic pathology sometimes necessitates the use of alternative vascular accesses, including access through the axillary artery. Data from a meta–analysis involving 1793 patients who underwent TAVR through trans axillary or transapical access showed a statistically significant reduction in 30–day mortality in the former group. We wait for future randomized trials to confirm the consistency of these data. Clinical case 71–year–old man, smoker, hypertensive and dyslipidaemic. In 2018, he underwent bilateral aorta–iliac–femoral bypass surgery for severe lower limb arteriopathy. Due to the onset of angina and dyspnea at rest, he went to the ER where a diagnosis of NSTEMI was made. On echocardiogram, there was evidence of severe high–gradient aortic stenosis while coronary angiography showed 80% RCA stenosis in the middle tract. Because of the high surgical risk (EUROSCORE II: 12%) and the evidence of bilateral femoral artery occlusion on CT–angiography, the Heart Team concluded to perform TAVR through percutaneous left trans–axillary access with concomitant percutaneous coronary revascularization. Obtained the backup access on the left radial artery, PTCA+DES was performed on RCA through the right radial access with subsequent placement of a pigtail catheter in the non–coronary sinus of Valsalva. Once the temporary pacemaker had been placed through the right femoral vein, an angio–guided puncture of the left axillary artery was performed with placement of the 14 Fr introducer for implantation of the Medtronic Evolut R 26 mm aortic biological prosthesis. Post–procedure ultrasound examination showed a residual mean aortic valve gradient of 17 mmHg with evidence of a small periprosthetic leak. Seven days after the procedure, the patient was discharged, asymptomatic and in good hemodynamic compensation without vascular complications. Conclusions Trans–axillary arterial access should be considered a viable alternative to transfemoral access for the performance of TAVR.

Changes in echocardiographic parameters over time in paradoxical low-flow low-gradient aortic stenosis.

To assess the progression of the disease and evolution of the main echocardiographic variables for quantifying AS in patients with severe low-flow low-gradient (LFLG) AS compared to other severe AS subtypes. Longitudinal, observational, multicenter study including consecutive asymptomatic patients with severe AS (aortic valve area, AVA < 1.0 cm²) and normal left ventricle ejection fraction (LVEF ≥ 50%). Patients were classified according to baseline echocardiography into: HG (high gradient; mean gradient ≥ 40 mmHg), NFLG (normal-flow low-gradient; mean gradient < 40 mmHg, indexed systolic volume (SVi) > 35mL/m2), or LFLG (mean gradient < 40 mmHg, SVi ≤ 35 mL/m²). AS progression was analyzed by comparing patients' baseline measurements and their last follow-up measurements or those taken prior to aortic valve replacement (AVR). Of the 903 included patients, 401 (44.4%) were HG, 405 (44.9%) NFLG, and 97 (10.7%) LFLG. Progression of the mean gradient in a linear mixed regression model was greater in low-gradient groups: LFLG vs. HG (regression coefficient 0.124, P = 0.005) and NFLG vs. HG (regression coefficient 0.068, P = 0.018). No differences were observed between the LFLG and NFLG groups (regression coefficient 0.056, P = 0.195). However, AVA reduction was slower in the LFLG group compared to the NFLG (P < 0.001). During follow-up, in conservatively-managed patients, 19.1% (n = 9) of LFLG patients evolved to having NFLG AS and 44.7% (n = 21) to having HG AS. In patients undergoing AVR, 58.0% (n = 29) of LFLG baseline patients received AVR with a HG AS. LFLG AS shows an intermediate AVA and gradient progression compared to NFLG and HG AS. The majority of patients initially classified as having LFLG AS changed over time to having other severe forms of AS, and most of them received AVR with a HG AS.