scholarly journals Low-Flow Low-Gradient and Low-Ejection Fraction Aortic Stenosis and Projected Aortic Valve Area Calculation: So Important but so Complicated. Let us Just Keep it Simple!

Author(s):  
Wilson Mathias Junior

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
E Buffle ◽  
A Papadis ◽  
C Seiler ◽  
S F De Marchi

Abstract Background Dobutamine has been proposed for the assessment of low-flow, low-gradient aortic stenosis (LFLGAS). However, in 1/3 of patients, no increase in stroke volume index can be achieved by Dobutamine, thus hampering its diagnostic value. This study evaluated the manoeuvre of cardiac preload augmentation by passive leg rise (PLR) alone or on top of Dobutamine to increase stroke volume index (SVI) in patients with LFLGAS, particularly in paradoxical LFLGAS. Methods We examined 50 patients with LFLGAS. Patients were assigned to the paradoxical LFLGAS (Paradox) group if left ventricular ejection fraction (LVEF) was ≥50% (n=29) and to the LFLGAS with low ejection fraction (LEF) group if LVEF was <50% (n=21). A modified Dobutamine stress echocardiography was performed in all patients with the following 4 steps: Rest, PLR alone, maximal Dobutamine infusion rate alone (Dmax) and Dobutamine plus PLR (Dmax + PLR). Three SVI measurement methods were used: first the left ventricular outflow tract velocity time integral (LVOT VTI) method, second the 2D Simpson's method, and third the 3D method. The corresponding aortic valve area (AVA) was obtained by the continuity equation. The increase of those values compared to measurements at rest was calculated and compared between the 3 stress steps. Results In the paradoxical LFLGAS group, delta SVI with Dmax assessed by both Simpson's (depicted in the figures) and 3D method was lowest compared to PLR and Dmax + PLR. PLR alone yielded an equally high delta SVI as Dmax + PLR in Simpson's and 3D, and was at least as high as Dmax across all methods. Dobutamine alone yielded the lowest delta transaortic aortic valve VTI. The highest delta aortic valve area resulted for Dmax + PLR. In the LEF group, the three stress steps yielded an equally high delta SVI with Simpson's method. Dmax never yielded a higher delta SVI than PLR alone. The yielded delta SVI was the highest for Dmax + PLR for both LVOT VTI and 3d method, although the difference was overall not as strong as in the Paradox group. Conclusions In patients with paradoxical LFLGAS, Dobutamine alone is inadequate for testing the potential of aortic valve opening augmentation. Instead, PLR alone or the addition of PLR plus Dobutamine should be used for that purpose. In low LVEF, adding PLR to Dobutamine also seems useful although its diagnostic added value is less evident than in the Paradox group. FUNDunding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Gottfried und Julia Bangerter-Rhyner-Foundation Paradox group Low ejection fraction group





Author(s):  
Anastasia Vamvakidou ◽  
Mohamed-Salah Annabi ◽  
Phillipe Pibarot ◽  
Edyta Plonska-Gosciniak ◽  
Ana G. Almeida ◽  
...  

Background: Low rest transaortic flow rate (FR) has been shown previously to predict mortality in low-gradient aortic stenosis. However limited prognostic data exists on stress FR during low-dose dobutamine stress echocardiography. We aimed to assess the value of stress FR for the detection of aortic valve stenosis (AS) severity and the prediction of mortality. Methods: This is a multicenter cohort study of patients with reduced left ventricular ejection fraction and low-gradient aortic stenosis (aortic valve area <1 cm 2 and mean gradient <40 mm Hg) who underwent low-dose dobutamine stress echocardiography to identify the AS severity and presence of flow reserve. The outcome assessed was all-cause mortality. Results: Of the 287 patients (mean age, 75±10 years; males, 71%; left ventricular ejection fraction, 31±10%) over a mean follow-up of 24±30 months there were 127 (44.3%) deaths and 147 (51.2%) patients underwent aortic valve intervention. Higher stress FR was independently associated with reduced risk of mortality (hazard ratio, 0.97 [95% CI, 0.94–0.99]; P =0.01) after adjusting for age, chronic kidney disease, heart failure symptoms, aortic valve intervention, and rest left ventricular ejection fraction. The minimum cutoff for prediction of mortality was stress FR 210 mL/s. Following adjustment to the same important clinical and echocardiographic parameters, among the three criteria of AS severity during stress, ie, the guideline definition of aortic valve area <1cm 2 and aortic valve mean gradient ≥40 mm Hg, or aortic valve mean gradient ≥40 mm Hg, or the novel definition of aortic valve area <1 cm 2 at stress FR ≥210 mL/s, only the latter was independently associated with mortality (hazard ratio, 1.72 [95% CI, 1.05–2.82]; P =0.03). Furthermore aortic valve area <1cm 2 at stress FR ≥210 mL/s was the only severe aortic stenosis criterion that was associated with improved outcome following aortic valve intervention ( P <0.001). Guideline-defined stroke volume flow reserve did not predict mortality. Conclusions: Stress FR during low-dose dobutamine stress echocardiography was useful for the detection of both AS severity and flow reserve and was associated with improved prediction of outcome following aortic valve intervention.



Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Li Ching Lee ◽  
Sher Lynn Lim ◽  
Huay Cheem Tan ◽  
Boon Lock Chia ◽  
Kian Keong Poh

Background and Aim : Low-flow, low-gradient (LFLG) severe aortic stenosis (AS) despite preserved left ventricular (LV) ejection fraction (EF) has been associated with more advanced stage of the disease, lower cardiac output (CO) and higher systemic afterload. We aim to characterize the LV performance determinants, including its vortex formation (VF) ability. Methods : Echocardiography was performed in 61 consecutive patients with severe AS (aortic valve area index (AVAI) ≤ 0.6 cm 2 /m 2 ) and preserved LVEF (≥ 50%). In addition to biplane LV measurements, AS severity indices and Tei index were measured. Hemodynamic indices (including systemic vascular resistance (SVR) and valvulo-arterial impedance (VAI)) were calculated. VF index (VFI) was obtained from 4 X (1-β)/πX α 3 X LVEF where β is the fraction of total transmitral diastolic stroke volume (SVol) contributed by atrial contraction (assessed by time velocity integral of the mitral E and A waves) and α is the end diastolic volume (EDV) 1/3 divided by mitral annular diameter during early diastole. Patients were categorized by their LV SVol index (SVI). LFLG group consisted of SVI < 45ml/m 2 . Results : Mean VFI was 2.67±1.1; AVAI, 0.50±0.09 cm 2 /m 2 . Though AVAI was slightly lower in LFLG, dimensionless index and aortic valve resistance were similar and associated with no difference in LV mass and volume between the 2 groups. VFI was significantly reduced in the LFLG, 2.37±0.9 vs 3.12±1.3 ( P =0.01), However other LV functional parameters including Tei index and LVEF were similar (Table ). LFLG was associated with higher SVR and VAI (Table ). In LFLG, the only significant correlates of VFI were SVR (r=0.38), VAI (0.37) and stroke work index (0.36); all P s<0.05. VFI did not correlate to these parameters in the non-LFLG group. Conclusion : In LFLG severe AS, increased afterload and suboptimal LV vortex formation ability contribute to lower CO/SV. VFI provides useful insights in understanding this relatively new entity. Comparison of echocardiographic and haemodynamic data in LFLG and non-LFLG groups



Heart ◽  
2017 ◽  
Vol 104 (3) ◽  
pp. 222-229 ◽  
Author(s):  
Praveen Mehrotra ◽  
Katrijn Jansen ◽  
Timothy C Tan ◽  
Aidan Flynn ◽  
Judy W Hung

ObjectiveCurrent guidelines define severe aortic stenosis (AS) as an aortic valve area (AVA)≤1.0 cm2, but some authors have suggested that the AVA cut-off be decreased to 0.8 cm2. The aim of this study was, therefore, to better describe the clinical features and prognosis of patients with an AVA of 0.8–0.99 cm2.MethodsPatients with isolated, severe AS and ejection fraction ≥55% with an AVA of 0.8–0.99 cm2 (n=105) were compared with those with an AVA<0.8 cm2 (n=155) and 1.0–1.3 cm2 (n=81). The endpoint of this study was a combination of death from any cause or aortic valve replacement at or before 3 years.ResultsPatients with an AVA of 0.8–0.99 cm2 group comprised predominantly normal-flow, low-gradient (NFLG) AS, while high gradients and low flow were more often observed with an AVA<0.8 cm2. The frequency of symptoms was not significantly different between an AVA of 0.8–0.99 cm2 and 1.0–1.3 cm2. The combined endpoint was achieved in 71%, 52% and 21% of patients with an AVA of 0.8 cm2, 0.8–0.99 cm2and 1.0–1.3 cm2, respectively (p<0.001). Among patients with an AVA of 0.8–0.99 cm2, NFLG AS was associated with a lower hazard (HR=0.40, 95% CI 0.23 to 0.68, p=0.001) of achieving the combined endpoint with outcomes similar to moderate AS in the first 1.5 years of follow-up. Patients with high-gradient or low-flow AS with an AVA of 0.8–0.99 cm2 had outcomes similar to those with an AVA<0.8 cm2. The sensitivity for the combined endpoint was 61% for an AVA cut-off of 0.8 cm2 and 91% for a cut-off of 1.0 cm2.ConclusionsThe outcomes of patients with AS with an AVA of 0.8–0.99 cm2 are variable and are more precisely defined by flow-gradient status. Our findings support the current AVA cut-off of 1.0 cm2.



2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
J Ferreira ◽  
M Beringuilho ◽  
D Faria ◽  
D Roque ◽  
H Ferreira ◽  
...  

Abstract Introduction According to current guidelines, given a patient with low-gradient (aortic valve maximum velocity &lt; 4m/s and/or aortic valve mean gradient &lt;40mmHg), aortic valve area (AVA) &lt; 1cm2 and low-flow (stroke volume (SV) &lt; 35mL/min/m2), with preserved left ventricle function (ejection fraction (EF) ≥50%), an integrated approach for assessment of aortic stenosis severity is proposed. We aimed to investigate whether mitral regurgitation can play a role in those cases, possibly being responsible for low antegrade systolic flow. Methods We retrospectively analysed 121 consecutive transthoracic echocardiograms (TTEs) of patients with severe aortic stenosis, with AVA &lt; 1.0cm2 as assessed by continuity equation. Patients with low ejection fraction (&lt; 50%) were excluded. We therefore included 84 patients (females 53,6%, mean age 79,1+-10 years). Stroke volume was assessed by Doppler at the left ventricle outflow tract (LVOT). We then compared the prevalence of more than mild mitral regurgitation among patients with low-gradient and low-flow and the other patients. Results 15 patients had both low-gradient, low-flow and preserved ejection fraction. There was a significant association regarding the presence of more than mild mitral regurgitation among these patients (p = 0.028, OR = 4.7, CI 95% 1.1-20.1). In these patients, it was also observed a higher prevalence of atrial fibrillation (p = 0.03, OR = 6.9, CI 95% 1.74-27.1), lower longitudinal systolic function of right ventricle as measured by TAPSE (16.6 vs 21.5mm, p = 0.028), and a tendency towards higher left atrial volume (113 vs 87mL, p = 0.06). Conclusions Given the findings that the prevalence of more than mild mitral regurgitation is higher in patients with severe aortic stenosis as assessed by AVA with both low-gradient, low-flow and preserved ejection fraction, we suggest that the presence of more than mild mitral regurgitation should be considered on the approach of aortic stenosis classification of these patients.



Author(s):  
Norio Kanamori ◽  
Tomohiko Taniguchi ◽  
Takeshi Morimoto ◽  
Hirotoshi Watanabe ◽  
Hiroki Shiomi ◽  
...  

See Editorial by Tribouilloy et al



2019 ◽  
Vol 35 (10) ◽  
pp. S24
Author(s):  
J. Grenier-Delaney ◽  
M. Annabi ◽  
I. Burwash ◽  
J. Bergler-Klein ◽  
J. Mascherbauer ◽  
...  


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