Mortensen, Nils Sofus Borg

BACKGROUND Patients with severe aortic stenosis (AS) exhibit heterogeneous flow-gradient hemodynamics and ventricular remodeling, which may influence symptomatic, functional, and structural responses to transcatheter aortic valve implantation (TAVI). Thus, we evaluated differences in functional recovery and reverse remodeling after transfemoral TAVI across flow-gradient phenotypes. METHODS In this sub-study of the COMPARE-TAVI 1 trial, 975 patients undergoing transfemoral TAVI were classified as classical low-flow low-gradient (cLFLG, 9.1%), paradoxical low-flow low-gradient (pLFLG, 7.7%), low-flow high-gradient (24.7%), normal-flow low-gradient (NFLG, 13.0%), and normal-flow high-gradient (45.4%). The primary functional outcome was longitudinal change in six-minute walk test distance (6MWTD) from baseline to 1 year follow-up. Secondary endpoints included changes in NYHA functional class and reverse remodeling from baseline to 1 year follow-up along with the incidence and risk of all-cause death and a composite MACE-endpoint. RESULTS Mean 6MWTD increased by 59±4 meters at 1-month (p=0.000) with no additional improvement at 1-year, but with heterogeneity between groups (p=0.000). Improvements among NFLG, cLFLG and low-flow high-gradient AS were comparable with normal-flow high-gradient AS, while pLFLG AS exhibited significantly increments at 1-year (−28±15 meters, p=0.007). Patients with NFLG, cLFLG and pLFLG were more symptomatic at baseline (NYHA ≥III: 40.5%, 57.3% and 50.6%, respectively, p=0.000). NYHA improved in all groups at 1-year follow-up (p=0.000), although persistent symptoms at 1-year were most frequent in pLFLG (NYHA ≥II; 38.7%, p=0.012). Reverse remodeling was also comparable between normal-flow high-gradient AS and NFLG, cLFLG, and low-flow high-gradient AS, respectively, but attenuated in pLFLG AS in both unadjusted and adjusted analyses. No differences were observed in the incidence and risk of all-cause death or the composite MACE-endpoint. CONCLUSION TAVI associates with functional recovery across all flow-gradient phenotypes, although with heterogeneous responses. Patients with NFLG showed comparable functional recovery and reverse remodeling at 1-year follow-up compared with normal-flow high-gradient AS, whereas pLFLG demonstrated attenuated benefits across all parameters.

BACKGROUND: Guidelines acknowledge that discordant low-gradient (LG) aortic stenosis (AS) may be severe, but verifying this can be challenging. Right heart catheterization during exercise is considered the gold standard for evaluating ventricular hemodynamics. No invasive studies have compared the hemodynamic response of discordant LG and severe AS during exercise. The aim of this observational study was to describe exercise hemodynamics in patients with asymptomatic discordant AS and left ventricular ejection fraction ≥50%. METHODS: Patients with aortic valve area ≤1.5 cm 2 underwent right heart catheterization at rest and during maximal exercise, measuring pulmonary capillary wedge pressure (PCWP), cardiac output (CO), and the PCWP/CO-slope. Patients were stratified into 3 groups: discordant LG AS (aortic valve area ≤1.0 cm 2 and mean gradient <40 mm Hg); moderate AS (aortic valve area >1.0 cm 2 ); and high-gradient (HG) severe AS (aortic valve area ≤1.0 cm 2 and mean gradient ≥40 mm Hg). RESULTS: Among 86 patients, 17 (20%) had discordant LG, 49 (57%) moderate, and 20 (23%) HG severe AS. The median PCWP/CO-slope was significantly steeper in discordant LG (3.3 [interquartile range, 2.1–4.3] mm Hg/L/min) and HG severe AS (2.7 [1.9–3.4] mm Hg/L per minute) compared with moderate AS (1.9 [0.7–2.8] mm Hg/L per minute), P =0.004. In a regression model adjusted for age, sex, and rest PCWP, systemic arterial compliance and AS severity were significantly associated with the PCWP/CO-slope. Furthermore, patients with discordant LG AS had a leftward-upward shift in the PCWP/CO-curve. CONCLUSIONS: Discordant LG and HG severe AS had similar hemodynamic responses to exercise with steeper PCWP/CO-slope than in moderate AS, suggesting that discordant LG AS is a severe form of AS. In addition, the left upwards shift in PCWP/CO-curve for discordant LG compared with HG severe AS indicates that this group also has heart failure with preserved ejection fraction physiology. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04913870 and NCT02395107.

Abstract Aims In aortic stenosis (AS), estimation of left ventricular (LV) contractility is difficult as most markers of systolic LV function are load-dependent. The ratio of LV ejection fraction (LVEF) to end-systolic wall stress (ESWS), has been widely accepted as a marker of contractility. However, no studies have evaluated if this ratio is affected by loading conditions. The study describes changes in ESWS and ESWS corrected LVEF after transcatheter aortic valve replacement (TAVR). Methods and results In this prospective study, 41 patients with severe AS underwent echocardiography, LV catheterisation, and computed tomography (CT) before and immediately after TAVR. ESWS was estimated from echocardiography alone (ESWSEcho), combining CT LV dimensions and echocardiographic gradients (ESWSCT + echo) and combining CT LV dimensions and invasively measured LV end-systolic pressure (ESWSCT + Invasive). ESWSecho, ESWSCT + echo and ESWSCT + Invasive all decreased significantly after TAVR (89 ± 48 vs. 57 ± 37 Kdynes/cm2, P &lt; 0.01; 69 ± 8 vs. 51 ± 8 Kdynes/cm2, P &lt; 0.01, and 197 ± 69 vs. 137 ± 48 Kpa/cm2, P &lt; 0.01, respectively). We observed weak to moderate associations between the methods. After TAVR, LVEF corrected to ESWSecho, ESWSCT + echo and ESWSCT + Invasive increased (0.93 ± 0.07 vs. 1.91 ± 2.1, P = 0.013; 0.36 ± 0.19 vs. 0.58 ± 0.33, P &lt; 0.01, and 0.3 ± 0.02 vs. 2.5 ± 1.5, P &lt; 0.01, respectively). Conclusion ESWSecho, ESWSCT + echo and ESWSCT + Invasive decreased significantly after TAVR suggesting they reflect afterload, but independent of method, ESWS corrected LVEF increased slightly post-TAVR, indicating load dependency.

Abstract Aims This study aims to describe the prevalence of discordant mild/moderate aortic stenosis (AS) in a population-based study and to identify the mechanisms that lead to reduced stroke volume (SV) and discordant moderate AS. Methods and results Discordant high-gradient (HG)-mild AS, defined as AVA &gt; 1.5 cm2 and mean pressure gradient (MG) of 20–40 mmHg, and discordant low-gradient (LG) moderate AS, defined as AVA 1.0–1.5 cm2 and MG &lt; 20 mmHg, were assessed in 883 individuals from the DANCAVAS screening study with aortic valve calcification and 257 individuals form the PROGRESSA study excluding those with left ventricular (LV) ejection fraction &lt; 50%. In the DANCAVAS cohort, 150 men had mild/moderate AS of which 34% had discordance between MG and AVA, representing 66% with moderate AS. Among 262 patients in the combined cohort, 39% had discordant LG-moderate AS and 6% discordant HG-mild AS. Compared with concordant mild and moderate AS, individuals with discordant LG-moderate AS were more likely to present with LV concentric remodelling geometry (26 vs. 33 vs. 45%, P &lt; 0.001), increased valvulo-arterial impedance (3.3 ± 0.7 vs. 3.6 ± 0.5 vs. 4.1 ± 0.7 mmHg/mL/m2, P &lt; 0.001), and reduced systemic arterial compliance (SAC) (0.74 ± 0.22 vs. 0.81 ± 0.22 vs. 0.64 ± 0.18 mL/m2/mmHg, P &lt; 0.001). Factors associated with SV index were relative wall thickness, LV end-diastolic diameter index, SAC, and LV remodelling pattern. Conclusion Discordant moderate AS is common, accounting for two-thirds of patients with moderate AS in the general male population. Patients with discordant LG-moderate AS have predominantly a concentric remodelling pattern with reduced SV. Reduced SV index was associated with signs of reduced vascular compliance, suggesting that altered vascular properties drive differences in remodelling patterns and discordant moderate AS.

Abstract Background Guidelines acknowledge that discordant low-gradient (LG) aortic stenosis (AS) may be severe, but verifying this can be challenging. Right heart catheterization during exercise is considered the gold standard evaluating ventricular hemodynamics. No invasive studies have compared the hemodynamic response of discordant LG and severe AS during exercise. Purpose To describe exercise hemodynamics in patients with asymptomatic discordant AS and left ventricular ejection fraction ≥50%, and to identify the variables associated with the steepness of the pulmonary capillary wedge pressure (PCWP)/cardiac output (CO) slope defined as (peak exercise PCWP-rest PCWP)/(peak exercise CO-rest CO). Methods Patients with aortic valve area (AVA) ≤1.5 cm² underwent right heart catheterization at rest and during maximal exercise measuring pulmonary artery pressures, PCWP, CO and PCWP/CO slope. Patients were stratified in three groups: 1) discordant LG AS (AVA ≤1.0 cm² and mean gradient &lt;40 mmHg); 2) moderate AS (AVA &gt;1.0 cm²) and 3) high-gradient severe AS (AVA ≤1.0 cm² and mean gradient ≥40 mmHg). Results Among 86 patients, 17 (20%) had discordant LG, 49 (57%) moderate, and 20 (23%) high-gradient severe AS. The PCWP/CO slope was significantly steeper in discordant LG: median 3.3 mmHg/L/min (interquartile range: 2.2 mmHg/L/min) and high-gradient severe AS: 2.7 mmHg/L/min (1.5 mmHg/L/min) compared to moderate AS: 1.9 mmHg/L/min (2.0 mmHg/L/min), p=0.004. In a linear regression model adjusted for age, sex and rest PCWP, systemic arterial compliance and AS severity were significantly associated with the PCWP/CO slope. Furthermore, patients with discordant LG AS had a leftward and upward shift in the PCWP/CO slope. Conclusions Discordant LG and high-gradient severe AS had similar hemodynamic response to exercise with steeper PCWP/CO slope than in moderate AS, suggesting that discordant LG AS is a severe form of AS. In addition, the left-upward shift in PCWP/CO slope for discordant LG compared to high-gradient severe AS indicates that, this group also has latent heart failure with preserved ejection fraction physiology.

AbstractAimsNew diastolic dysfunction (DD) guidelines were introduced in 2016 to replace the 2009 guidelines, but have not yet been evaluated in aortic stenosis (AS). We aimed to compare the 2009 and 2016 DD guidelines in severe AS patients in terms of association with left ventricular (LV) and left atrial (LA) remodeling, with pulmonary capillary wedge pressure (PCWP) at rest and exercise, and with prognosis.Methods and resultsWe included 212 patients with severe AS (112 undergoing AVR, 100 asymptomatic). Echocardiography, magnetic resonance imaging, and brain natriuretic peptides (BNP) were performed/measured. Thirty‐nine asymptomatic patients had PCWP measured during rest and maximal exertion. Asymptomatic patients were followed for 3.1 years for the combined endpoint of death, AVR or admission with heart failure. The 2009 and 2016 DD guidelines agreed poorly with each other (Cohens’ κ = .15). 2009 guidelines showed many ambiguous DD findings. With the 2016 guidelines, 20% of patients had indeterminate DD. DD grade 2 according to 2016 guidelines showed stronger association with symptom status, BNP, global longitudinal strain (GLS) and peak exercise PCWP than 2009 guidelines. For indeterminate DD patients according to 2009 guidelines, GLS above the median was associated with event‐free survival (HR .11 (95% CI .02–.53)). For neither guideline was DD associated with the combined endpoint in asymptomatic patients.ConclusionThe 2016 guidelines show a stronger association with BNP, GLS, and exercise PCWP than the 2009 guidelines. The 2016 guidelines result in 20% of patients with indeterminate DD; however, these patients may possibly be stratified according to GLS.

Background First-phase ejection fraction (EF1), the left ventricular (LV) ejection fraction (EF) until the time of peak transaortic velocity, is a novel marker of subclinical LV dysfunction able to predict adverse events in aortic stenosis (AS). This study investigated the association between end-systolic wall stress (ESWS) and EF1 in severe AS, as well as the prognostic value of EF1 in severe asymptomatic AS. Methods Two prospectively gathered cohorts of 94 asymptomatic patients and 108 symptomatic patients scheduled for aortic valve replacement (AVR), all with severe AS (aortic valve area <1 cm2) were stratified according to the median value of EF1 (33%). EF1 was defined as the EF at peak transaortic velocity. Asymptomatic patients were followed up for 3 years for the combined end-point of death, AVR or admission with heart failure. Results EF1 correlated with EF and was inversely associated with ESWS. In multivariate regression analysis, ESWS (p<0.001) and replacement fibrosis measured by MRI (p=0.02) were associated with EF1. Among asymptomatic patients, EF1 above the median was associated with the combined primary endpoint (HR=0.53 (95% CI 0.33 to 0.87)), while global longitudinal strain and EF were not. Among 42 patients with discordant AS (mean gradient <40 mm Hg), EF1 above median was associated with the primary endpoint (HR 0.28 (95% CI 0.12 to 0.61)). Conclusion EF1 is an afterload-dependent measure that is associated with events in patients with asymptomatic severe AS. The afterload dependency of EF1 may be useful in timing of risk stratification in patients with discordant AS. Trial registration numbers NCT02395107 and NCT02316587.

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Danish Heart Association. Background First-phase ejection fraction (EF1), the ejection fraction (EF) until the time of peak systolic flow may be a sensitive marker of subclinical left ventricular (LV) dysfunction. This study investigated the prognostic value of EF1 in asymptomatic and symptomatic severe aortic stenosis (AS). Methods This study included 94 asymptomatic and 108 symptomatic patients with severe AS. The prognostic value of EF1 was compared with other echocardiographic markers and magnetic resonance imaging (MRI) measured end-systolic wall stress and late gadolinium enhancement fibrosis (LGE). Asymptomatic patients were followed up for 3.0 years (primary outcome death or aortic valve replacement). Symptomatic patients were followed up for 4.3 years (primary outcome death). Results In multivariate regression analysis wall stress (p &lt; 0.001) and LGE (p = 0.03) were associated with EF1. In the asymptomatic cohort EF1 was significantly associated with the end-point, especially among the subgroup of patients with a mean gradient &lt; 40 mmHg (HR 0.91, p = 0.005), while global longitudinal strain was not. In the surgical cohort, EF1 was borderline associated with death (p = 0.08) which was significant after correction for LGE (HR 0.90, p = 0.02). Conclusion EF1 is a predictor of death or AVR in asymptomatic AS, especially among discordantly graded patients with low area and low gradient. Univariate β (95% CI) p-value Multivariate β (95% CI) p-value Age (years) .03 (-.09 to .16) 0.58 .03 (-.12 to .18) 0.69 Sex (male) -.12 (-2.26 to 2.03) 0.91 .24 (-2.31 to 2.80) 0.85 Hypertension -.08 (-2.22 to 2.07) 0.95 Aortic valve area (0.01 cm2) .09 (.04 to .14) 0.001 Aortic mean gradient (mmHg) -.02 (-.08 to .04) 0.56 LV end-diastolic volume (ml) -.07 (-.11 to -.03) &lt;0.001 LV end-systolic volume (ml) -.17 (-.22 to -.12) &lt;0.001 -.07 (-.15 to .02) 0.11 LV ejection fraction (%) .28 (.19 to .38) &lt;0.001 LV peak ejection time (ms) -.07 (-.16 to .02) 0.13 LGE fibrosis -3.04 (-5.67 to -.42) 0.02 -2.64 (-4.99 to -.30) 0.03 Wall stress (kdynes/m3) -.10 (-.13 to -.08) &lt;0.001 -.08 (-.12 to -.04) &lt;0.001 Multivariate linear regression analysis for associations with first phase ejection fraction. LV is left ventricular, LGE late gadolinium enhancement Abstract Figure. AVR-free survival according to EF1