Dataset Information

Rationale and design of SAVI-AoS: A physiologic study of patients with symptomatic moderate aortic valve stenosis and preserved left ventricular ejection fraction.

ABSTRACT:

Background

Moderate aortic valve stenosis occurs twice as often as severe aortic stenosis (AS) and carries a similarly poor prognosis. Current European and American guidelines offer limited insight into moderate AS (MAS) patients with unexplained symptoms. Measuring valve physiology at rest while most patients experience symptoms during exertion might represent a conceptual limitation in the current grading of AS severity. The stress aortic valve index (SAVI) may delineate hemodynamically significant AS among patients with MAS.

Objectives

To investigate the diagnostic value of SAVI in symptomatic MAS patients with normal left ventricular ejection fraction (LVEF ≥ 50%): aortic valve area (AVA) > 1 cm² plus either mean valve gradient (MG) 15-39 mmHg or maximal aortic valve velocity (AOV max) 2.5-3.9 m/s. Short-term objectives include associations with symptom burden, functional capacity, and cardiac biomarkers. Long-term objectives include clinical outcomes.

Methods and results

Multicenter, non-blinded, observational cohort. AS severity will be graded invasively (aortic valve pressure measurements with dobutamine stress testing for SAVI) and non-invasively (echocardiography during dobutamine and exercise stress). Computed tomography (CT) of the aortic valve will be scored for calcium, and hemodynamics simulated using computational fluid dynamics. Cardiac biomarkers and functional parameters will be serially monitored. The primary objective is to see how SAVI and conventional measures (MG, AVA and Vmax) correlate with clinical parameters (quality of life survey, 6-minute walk test [6MWT], and biomarkers).

Conclusions

The SAVI-AoS study will extensively evaluate patients with unexplained, symptomatic MAS to determine any added value of SAVI versus traditional, resting valve parameters.

SUBMITTER: Eerdekens R

PROVIDER: S-EPMC9157233 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Rationale and design of <b>SAVI-AoS:</b> A <b>physiologic</b> study of patients with symptomatic moderate aortic valve stenosis and preserved left ventricular ejection fraction.

Eerdekens Rob R Tonino Pim P Zelis Jo J Adrichem Rik R Ahn Jung-Min JM Demandt Jesse J Eftekhari Ashkan A El Farissi Mohamed M Freeman Phillip P Rahman Ihdayhid Abdul A Kakouros Nikolaos N Kim Dae-Hee DH Lee Seung-Ah SA Van Mieghem Nicolas M NM Qureshi Waqas W Johnson Nils P NP

International journal of cardiology. Heart & vasculature 20220527

<h4>Background</h4>Moderate aortic valve stenosis occurs twice as often as severe aortic stenosis (AS) and carries a similarly poor prognosis. Current European and American guidelines offer limited insight into moderate AS (MAS) patients with unexplained symptoms. Measuring valve physiology at rest while most patients experience symptoms during exertion might represent a conceptual limitation in the current grading of AS severity. The stress aortic valve index (SAVI) may delineate hemodynamicall ...[more]

PMID: 35663622

Similar Datasets

Project description:Background Moderate aortic stenosis ( MAS ) has not been extensively studied and characterized, as no published study has been specifically devoted to this condition. Methods and Results We aimed to describe the characteristics of patients with MAS and to evaluate their long-term survival compared with that of the general population. This study included 508 patients (mean±SD age, 75±11 years) with MAS (aortic valve area between 1 and 1.5 cm2; mean±SD aortic valve area, 1.2±0.15 cm2) and preserved left ventricular ejection fraction. Patients were mostly (86.4%) asymptomatic or minimally symptomatic, 78.3% had hypertension, 36.2% were diabetics, and 48.3% had dyslipidemia. Each patient with MAS was matched for the average survival (per year) of all patients of the same age and same sex from our region (Somme department, north of France). During follow-up (median 47 months), 113 patients (22.2%) underwent aortic valve replacement for severe AS. The mean±SD time between inclusion and surgery was 37±22 months. During follow-up, 255 patients (50.2%) died. The 6-year survival of patients with MAS was lower than the expected survival (53±2% versus 65%). In multivariate analysis, age (hazard ratio, 1.04 [95% CI, 1.02-1.05]; P<0.001), prior atrial fibrillation (hazard ratio, 1.35 [95% CI, 1.05-1.73]; P=0.019), and Charlson comorbidity index (hazard ratio, 1.11 [95% CI, 1.05-1.18]; P=0.002) were associated with increased mortality. Aortic valve replacement was associated with better survival (hazard ratio, 0.38 [95% CI, 0.27-0.54]; P<0.001). Conclusions The results of this study show that patients with MAS present many cardiovascular risk factors, a high rate of surgery during follow-up, and increased mortality compared with the general population mainly related to associated comorbidities. Patients with MAS should, therefore, be managed for their cardiovascular risk factors and comorbidities. They require close follow-up, especially when the aortic valve area is close to 1 cm2, as aortic valve replacement performed when patients transition to severe AS and develop indications for surgery during follow-up is associated with better survival.

Project description:BackgroundWhy some but not all patients with severe aortic stenosis (SevAS) develop otherwise unexplained reduced systolic function is unclear. We investigate the hypothesis that reduced creatine kinase (CK) capacity and flux is associated with this transition.MethodsWe recruited 102 participants to 5 groups: moderate aortic stenosis (ModAS) (n=13), SevAS, left ventricular (LV) ejection fraction ≥55% (SevAS-preserved ejection fraction, n=37), SevAS, LV ejection fraction <55% (SevAS-reduced ejection fraction, n=15), healthy volunteers with nonhypertrophied hearts with normal systolic function (normal healthy volunteer, n=30), and patients with nonhypertrophied, non-pressure-loaded hearts with normal systolic function undergoing cardiac surgery and donating LV biopsy (non-pressure-loaded heart biopsy, n=7). All underwent cardiac magnetic resonance imaging and 31P magnetic resonance spectroscopy for myocardial energetics. LV biopsies (AS and non-pressure-loaded heart biopsy) were analyzed for CK total activity, CK isoforms, citrate synthase activity, and total creatine. Mitochondria-sarcomere diffusion distances were calculated by using serial block-face scanning electron microscopy.ResultsIn the absence of failure, CK flux was lower in the presence of AS (by 32%, P=0.04), driven primarily by reduction in phosphocreatine/ATP (by 17%, P<0.001), with CK kf unchanged (P=0.46). Although lowest in the SevAS-reduced ejection fraction group, CK flux was not different from the SevAS-preserved ejection fraction group (P>0.99). Accompanying the fall in CK flux, total CK and citrate synthase activities and the absolute activities of mitochondrial-type CK and CK-MM isoforms were also lower (P<0.02, all analyses). Median mitochondria-sarcomere diffusion distances correlated well with CK total activity (r=0.86, P=0.003).ConclusionsTotal CK capacity is reduced in SevAS, with median values lowest in those with systolic failure, consistent with reduced energy supply reserve. Despite this, in vivo magnetic resonance spectroscopy measures of resting CK flux suggest that ATP delivery is reduced earlier, at the moderate AS stage, where LV function remains preserved. These findings show that significant energetic impairment is already established in moderate AS and suggest that a fall in CK flux is not by itself a necessary cause of transition to systolic failure. However, because ATP demands increase with AS severity, this could increase susceptibility to systolic failure. As such, targeting CK capacity and flux may be a therapeutic strategy to prevent and treat systolic failure in AS.

Project description:Heart failure with preserved ejection fraction (HFpEF) is characterized by complex pathophysiology including an impaired diastolic reserve. We recently showed that milrinone favourably modifies filling pressures at rest and during exertion in HFpEF patients; however, the responsible mechanism is uncertain. The objective of this study was to develop a clearer understanding of the acutely modifiable physiologic parameters that may be targeted in HFpEF. We conducted computer modelling simulations based on invasive haemodynamic assessments, by right heart catheterization, in HFpEF patients at baseline and in response to milrinone. Our aim was to develop a detailed understanding of the physiologic mechanisms, which accounted for the observed actions. The resultant circulatory model of HFpEF encompassed the left ventricular (LV) end-systolic and end-diastolic pressure-volume relations, together with stressed blood volume, heart rate, and arterial mechanics. To support the modelled action of milrinone, we conducted complementary LV conductance catheter and echocardiography studies in sheep to evaluate LV end-systolic and end-diastolic pressure-volume relations. In HFpEF patients, the acute haemodynamic effects of intravenous milrinone (n = 10) administration compared with placebo (n = 10) included significant reductions in right atrial pressure (7 ± 1 to 3 ± 1 mmHg, P < 0.001) and pulmonary capillary wedge pressure (13 ± 1 to 8 ± 1 mmHg, P < 0.001), while cardiac index increased (2.77 ± 0.19 to 3.15 ± 0.14 L/min/m2 , P < 0.05), and mean arterial pressure remained unchanged (95 ± 2 to 93 ± 3 mmHg, P = not significant). Computer simulations showed that these haemodynamic effects were explained by a concomitant 31% reduction in stressed blood volume together with 44% increase in LV end-systolic elastance (LV Ees ). Individually, changes in these parameters were not sufficient to explain the haemodynamic effects of milrinone. In vivo studies conducted in sheep (n = 5) showed that milrinone reduced LV filling pressure (8.0 ± 0.8 to 2.7 ± 0.6 mmHg, P < 0.01) and increased LV Ees (0.96 ± 0.07 to 2.07 ± 0.49, P < 0.05), while no significant effect on LV stiffness was observed (0.038 ± 0.003 to 0.034 ± 0.008, P = not significant). These data demonstrate that stressed blood volume in HFpEF represents a relevant physiologic target in HFpEF; however, concomitant modulation of other cardiovascular parameters including LV contractility may be required to achieve desirable haemodynamic effects.

Project description:AimsTranscatheter aortic valve implantation (TAVI) has emerged as the treatment of choice for many patients with severe symptomatic aortic stenosis. We sought to identify the echocardiographic predictors of 30-day and 1-year outcomes after TAVI in patients with preserved or reduced left ventricular ejection fraction (LVEF).MethodsThis single-centre study included 618 aortic stenosis patients (mean age 82 ± 6 years, 47.1% male; 74.8% LVEF > 50%) who underwent balloon-expandable TAVI between July 2009 and October 2018 in our hospital. All patients completed at least 6 months of follow-up by medical history review or telephone interview (median 24, quartiles 12-42 months). The primary endpoint was all-cause death.ResultsAll-cause mortality rate was 5.2% (LVEF > 50%: 4.3% vs. LVEF ≤ 50%: 7.7%, p = 0.141) at 30 days and 15.4% (LVEF > 50%: 14.7% vs. LVEF ≤ 50%: 17.3%, p = 0.443) at 12 months post TAVI. Overall all-cause mortality rate was 45.1% (LVEF > 50%: 44.6% vs. LVEF ≤ 50%: 46.8%, p = 0.643). Mean survival time post TAVI was 51 months [95% CI (48; 55)]. In TAVI patients with LVEF > 50%, multivariate Cox regression analysis revealed several independent predictors for increased risk of death after adjusting for echocardiographic and clinical covariates: TAPSE (≤ 17 vs. > 17 mm, HR 1.528, p = 0.016) and sPAP (> 30 vs. ≤ 30 mmHg, HR 1.900, p = 0.002) for overall mortality, E/E' septal for 30-day mortality (> 21 vs. ≤ 21, HR 14.462, p = 0.010) and 12-month mortality (> 21 vs. ≤ 21, HR 1.881, p = 0.026). In TAVI patients with LVEF ≤ 50%, no independent echocardiographic predictors for outcome could be identified.ConclusionsLVEF is not a predictor of short- and long-term mortality after TAVI. In patients with preserved LVEF, left ventricular filling pressure (E/E´), systolic pulmonary artery pressure (sPAP), and TAPSE are echocardiographic risk factors for increased mortality post TAVI.