Quantification Of Aortic Regurgitation Research Articles

Aortic Regurgitation: From Valvular to Myocardial Dysfunction.

Chronic aortic regurgitation (AR) leads to volume overload in the left ventricle (LV), which is well tolerated for years. In this condition, the LV usually dilates with minimal reduction in the ejection fraction (EF), even in the absence of symptoms. Echocardiography is the primary imaging test used to quantify AR. However, no single assessment of Doppler measures is accurate and precise in individual patients; therefore, the integration of multiple parameters is necessary. Recent guidelines recommend surgical treatment for severe AR in patients who are symptomatic or have an LVEF < 55% and an end-systolic diameter > 50 mm. Nevertheless, advances in imaging technology have improved the quantification of AR and the assessment of LV subclinical dysfunction. It is widely recognized that patients who undergo aortic valve replacement/repair (AVR) due to symptoms or a low LVEF experience worse outcomes than those undergoing AVR for non-Class I indications. In fact, subclinical irreversible myocardial damage may occur in clinically well-compensated and closely monitored patients while awaiting formal surgical indications. This condition could be prevented by the use of multimodal imaging parameters, in particular longitudinal LV strain and magnetic resonance imaging. In addition, better cut-off values for mortality predictors should be established. This review aims to identify simple models that integrate several echocardiographic and cardiac magnetic resonance-derived parameters to predict the optimal timing of surgical treatment in asymptomatic patients with chronic severe AR.

Quantifying aortic valve regurgitation in patients with congenital aortic valve disease by 2D and 4D flow magnetic resonance analysis

BackgroundIn congenital aortic valve disease, quantifying aortic regurgitation (AR) varies by the measurement site. Our study aimed to identify the optimal site for AR assessment using 2D and 4D MR flow measurements, with a focus on vortices. MethodsWe retrospectively analysed 31 patients with congenital aortic valve disease, performing 2D and 4D MR flow measurements at the aortic valve, sinotubular junction (STJ), ascending aorta (AAo), and using midpulmonary artery measurements as a reference.We assessed percentage AR and net forward volumes, calculated linear correlations, and plotted Bland-Altman plots. Net forward flow at all aortic sites were correlated with the main pulmonary artery. Differences in AR between 2D and 4D flows were linked to vortices detected by 4D streamlines. ResultsThe best agreement in % AR between 2D and 4D flows was at the aortic valve (mean difference 4D2D -2.9%, limits of agreement 8.7% to −14.3%; r2 = 0.7). Correlations weakened at STJ and AAo. Vortices in the ascending aorta led to AR overestimation in 2D measurements. Net forward flow at the aortic valve by 4D flow correlated closer with main pulmonary artery than did 2D flow. (Mean difference for 2D and 4D MR flow 7.5 ml and 4.2 ml, respectively). ConclusionsFor congenital aortic valve disease, the most accurate AR quantification occurs at the aortic valve using 2D and 4D MR flow. Notably, vortices in the ascending aorta can result in AR overestimation with 2D MR flow.

Rationale and design of the ELEANOR trial early aortic valve surgery versus watchful waiting strategy in severe asymptomatic aortic regurgitation, ACRONYM: ELEANOR

BackgroundThe optimal treatment of patients with severe symptomatic aortic regurgitation (AR) is state-of-the-art surgery. Asymptomatic patients with advanced left ventricular (LV) dilatation and/or impaired ejection fraction should undergo surgical treatment, but there is no guidelines consensus on cut-off values for this recommendation. Multimodality imaging has brought new tools for the accurate selection of asymptomatic patients at risk of early clinical deterioration, however, prospective and randomized data are pending. Cardiac magnetic resonance (CMR)-derived AR quantification along with LV remodeling assessment appears to be the most accurate tool for a selection of such patients at risk. Trial designThe objective of our prospective and multicenter study is to determine whether patients at risk of early clinical deterioration as per CMR assessment will benefit from early surgical treatment. The study is designed as a superiority trial to demonstrate that early surgical treatment is safe and more effective than the standard treatment. A total of 217 asymptomatic patients with severe AR, but without current guidelines-based surgical indication, will be enrolled across all centers. We expect 24 % of patients identified as high clinical risk and therefore eligible for 1:1 randomization to early surgical treatment within 3 months or a watchful waiting strategy. Follow-up will be annual. We expect a complete restoration of LV size and function along with improved quality of life and physical performance in a short-term follow-up of 12 months. The primary endpoint will be a composite safety and efficacy with all criteria mandatory: 15 % or larger reduction of baseline CMR-derived LV end-diastolic volume index, LV ejection fraction >50 %, and no major adverse cardiovascular events. The annual follow-up will continue for a minimum of 4 years until the required number of endpoints is achieved to show a statistically significant difference in cardiovascular morbidity and mortality in early surgically treated patients. ConclusionThe ELEANOR trial is the first multicenter randomized controlled study to compare early surgical treatment with a watchful waiting strategy in asymptomatic patients with chronic severe AR at high risk of early clinical deterioration as per CMR assessment but without guidelines-based indications for surgical treatment.

Aortic regurgitation: multimodal assessment of quantification and impact.

The assessment of severity of aortic regurgitation (AR) by transthoracic echocardiography (TTE) remains challenging in routine practice. Contemporary guidelines recommend cardiovascular magnetic resonance imaging (CMR) in patients with significant disease and suboptimal TTE images. The objective of this study was to assess the role of CMR in the evaluation of severity of AR and to compare both modalities in the quantification of regurgitation and left ventricular volumes. Fifty consecutive patients who had isolated chronic AR and who underwent TTE and CMR within an interval of less than three months between May 2009 and June 2020 were included. The main indication for CMR was difficulties in quantifying AR, either because of lack of multiparametric analysis (only one method possible) or because of discrepancies in the different methods by TTE. In 25 patients, precise grading of AR was not possible by echocardiography. Among them, CMR finally detected seven patients with mild AR, 11 with moderate AR and seven with severe AR. For the 25 patients who had AR quantification by TTE, there was concordance between TTE and CMR in only seven patients (28%), and the AR was re-graded by CMR in 18 patients, including eight patients with severe AR by TTE and moderate AR by CMR. The concordance between TTE and CMR was weakly significant (intraclass correlation coefficient = 0.39, 95% confidence interval: 0.003-0.67, p = 0.02). There was a moderate correlation between left ventricular volumes measured by TTE and by CMR (left ventricular end-diastolic volume: r = 0.57; p = 0.01; left ventricular end-systolic volume: r = 0.47, p = 0.01) but regurgitant volumes were not correlated (r = 0.04; p = 0.8). No TTE parameter of quantification was correlated with regurgitant volume measured by CMR. The concordance of AR quantification by CMR and TTE was weak. CMR re-graded some patients with severe AR by TTE into moderate AR. This should motivate practitioners to systematically assess all significant AR by CMR in order to improve quantification and optimise clinical management.

Angiographic quantification of aortic regurgitation following myval octacor implantation; independent core lab adjudication

BackgroundThe balloon expandable Myval transcatheter heart valve (THV) showed encouraging results regarding residual aortic regurgitation (AR) from multiple observational studies. The newly designed Myval Octacor has been introduced recently, aiming for a reduction in AR and improved performance. ObjectivesThe focus of this study is to report the incidence of AR using the validated quantitative Videodensitometry angiography technology (qLVOT-AR%) in the first in human use of the Myval Octacor THV system. MethodologyWe report on the first in human use of the Myval Octacor THV system in 125 patients in 18 Indian centres. Independent retrospective analysis of the final aortograms following implantation of the Myval Octacor was performed using the CAAS-A-Valve software. AR is reported as a regurgitation fraction. The previously validated cutoff values have been used to identify ≥moderate AR (RF% >17%), mild (6% < RF% ≤17%), and none or trace AR (RF% ≤ 6%). ResultsFinal aortogram was analysable for 103 patients (84.4%) among the 122 available aortograms. 64 (62%) patients, had tricuspid aortic valve (TAV), 38 (37%) with bicuspid AV (BAV), and one with unicuspid AV. The median absolute RF% was 2% [1, 6], moderate or more AR incidence was 1.9%, mild AR in 20.4%, and none or trace AR in 77.7%. The two cases with RF% >17% were in the BAV group. ConclusionThe initial results of Myval Octacor using quantitative angiography-derived regurgitation fraction demonstrated a favourable outcome regarding residual AR, possibly due to improved device design. Results must be confirmed in a larger randomised study, including other imaging modalities.

Quantitative evaluation of aortic valve regurgitation in 4D flow cardiac magnetic resonance: at which level should we measure?

PurposeTo find the best level to measure aortic flow for quantification of aortic regurgitation (AR) in 4D flow CMR.MethodsIn 27 congenital heart disease patients with AR (67% male, 31 ± 16 years) two blinded observers measured antegrade, retrograde, net aortic flow volumes and regurgitant fractions at 6 levels in 4D flow: (1) below the aortic valve (AV), (2) at the AV, (3) at the aortic sinus, (4) at the sinotubular junction, (5) at the level of the pulmonary arteries (PA) and (6) below the brachiocephalic trunk. 2D phase contrast (2DPC) sequences were acquired at the level of PA. All patients received prior transthoracic echocardiography (TTE) with AR severity grading according to a recommended multiparametric approach.ResultsAfter assigning 2DPC measurements into AR grading, agreement between TTE AR grading and 2DPC was good (κ = 0.88). In 4D flow, antegrade flow was similar between the six levels (p = 0.87). Net flow was higher at level 1–2 than at levels 3–6 (p < 0.05). Retrograde flow and regurgitant fraction at level 1–2 were lower compared to levels 3–6 (p < 0.05). Reproducibility (inter-reader agreement: ICC 0.993, 95% CI 0.986–0.99; intra-reader agreement: ICC 0.982, 95%CI 0.943–0.994) as well as measurement agreement between 4D flow and 2DPC (ICC 0.994; 95%CI 0.989 – 0.998) was best at the level of PA.ConclusionFor estimating severity of AR in 4D flow, best reproducibility along with best agreement with 2DPC measurements can be expected at the level of PA. Measurements at AV or below AV might underestimate AR.

In vitro Assessment of Aortic Regurgitation Using Four-Dimensional Flow Magnetic Resonance Imaging.

Aortic regurgitation (AR) refers to backward blood flow from the aorta into the left ventricle (LV) during ventricular diastole. The regurgitant jet arising from the complex shape is characterized by the three-dimensional flow and high-velocity gradient, sometimes limiting an accurate measurement of the regurgitant volume using 2D echocardiography. Recently developed four-dimensional flow magnetic resonance imaging (4D flow MRI) enables three-dimensional volumetric flow measurements, which can be used to accurately quantify the amount of the regurgitation. This study focuses on (i) magnetic resonance compatible AR model fabrication (dilatation, perforation, and prolapse) and (ii) systematic analysis of the performance of 4D flow MRI in AR quantification. The results indicated that the formation of the forward and backward jets over time was highly dependent on the types of AR origin. The amount of regurgitation volume bias for the model types were -7.04%, -33.21%, 6.75%, and 37.04% compared to the ground truth (48 mL) volume measured from the pump stroke volume. The largest error of the regurgitation fraction was around 12%. These results indicate that careful selection of imaging parameters is required when absolute regurgitation volume is important. The suggested in vitro flow phantom can easily be modified to simulate other valvular diseases such as aortic stenosis or bicuspid aortic valve (BAV) and can be used as a standard platform to test different MRI sequences in the future.

&lt;em&gt;In vitro&lt;/em&gt; Assessment of Aortic Regurgitation Using Four-Dimensional Flow Magnetic Resonance Imaging

Aortic regurgitation (AR) refers to backward blood flow from the aorta into the left ventricle (LV) during ventricular diastole. The regurgitant jet arising from the complex shape is characterized by the three-dimensional flow and high-velocity gradient, sometimes limiting an accurate measurement of the regurgitant volume using 2D echocardiography. Recently developed four-dimensional flow magnetic resonance imaging (4D flow MRI) enables three-dimensional volumetric flow measurements, which can be used to accurately quantify the amount of the regurgitation. This study focuses on (i) magnetic resonance compatible AR model fabrication (dilatation, perforation, and prolapse) and (ii) systematic analysis of the performance of 4D flow MRI in AR quantification. The results indicated that the formation of the forward and backward jets over time was highly dependent on the types of AR origin. The amount of regurgitation volume bias for the model types were -7.04%, -33.21%, 6.75%, and 37.04% compared to the ground truth (48 mL) volume measured from the pump stroke volume. The largest error of the regurgitation fraction was around 12%. These results indicate that careful selection of imaging parameters is required when absolute regurgitation volume is important. The suggested in vitro flow phantom can easily be modified to simulate other valvular diseases such as aortic stenosis or bicuspid aortic valve (BAV) and can be used as a standard platform to test different MRI sequences in the future.

Assessment of Asymptomatic Severe Aortic Regurgitation by Doppler-Derived Echo Indices: Comparison with Magnetic Resonance Quantification.

Reliable quantification of aortic regurgitation (AR) severity is essential for clinical management. We aimed to compare quantitative and indirect echo-Doppler indices to quantitative cardiac magnetic resonance (CMR) parameters in asymptomatic chronic severe AR. Methods and Results: We evaluated 104 consecutive patients using echocardiography and CMR. A comprehensive 2D, 3D, and Doppler echocardiography was performed. The CMR was used to quantify regurgitation fraction (RF) and volume (RV) using the phase-contrast velocity mapping technique. Concordant grading of AR severity with both techniques was observed in 77 (74%) patients. Correlation between RV and RF as assessed by echocardiography and CMR was relatively good (rs = 0.50 for RV, rs = 0.40 for RF, p < 0.0001). The best correlation between indirect echo-Doppler and CMR parameters was found for diastolic flow reversal (DFR) velocity in descending aorta (rs = 0.62 for RV, rs = 0.50 for RF, p < 0.0001) and 3D vena contracta area (VCA) (rs = 0.48 for RV, rs = 0.38 for RF, p < 0.0001). Using receiver operating characteristic analysis, the largest area under curve (AUC) to predict severe AR by CMR RV was observed for DFR velocity (AUC = 0.79). DFR velocity of 19.5 cm/s provided 78% sensitivity and 80% specificity. The AUC for 3D VCA to predict severe AR by CMR RV was 0.73, with optimal cut-off of 26 mm2 (sensitivity 80% and specificity 66%). Conclusions: Out of the indirect echo-Doppler indices of AR severity, DFR velocity in descending aorta and 3D vena contracta area showed the best correlation with CMR-derived RV and RF in patients with chronic severe AR.

Quantitative assessment of aortic regurgitation following transcatheter aortic valve replacement

ABSTRACT Introduction: Transcatheter aortic valve replacement (TAVR) is expanding to lower risk and younger patients with severe symptomatic aortic valve disease. Despite clinical and technological improvements, post-procedural aortic regurgitation (AR) remains a limitation of TAVR, particularly when compared to surgical aortic valve replacement. Although several methods for AR quantification after TAVR are currently available, its exact graduation in everyday clinical practice remains challenging. Areas covered: This review describes the currently available evaluation methods of AR after TAVR, with a special emphasis on the quantitative assessment using videodensitometric angiography, echocardiography and cardiac magnetic resonance imaging. Expert opinion: In the majority of clinical scenarios, satisfactory evaluation of post-TAVR AR can be achieved with a combination of post-procedural angiography, hemodynamic indices and transthoracic echocardiography. Nevertheless, some TAVR patients show ‘intermediate’ forms of post-procedural AR, in which quantitative evaluation is mandatory for prognostic purposes and further decision-making. Notably, interpretation of quantitative measures early post-TAVR is challenging because of the lack of left ventricular enlargement. Video-densitometric angiography is an emerging method that appears to be clinically attractive for immediate post-TAVR assessment, but requires further validation in everyday clinical practice.

Predicting the need of aortic valve surgery in patients with chronic aortic regurgitation: a comparison between cardiovascular magnetic resonance imaging and transthoracic echocardiography

To compare the ability of cardiac magnetic resonance tomography (CMR) and transthoracic echocardiography (TTE) to predict the need for valve surgery in patients with chronic aortic regurgitation on a mid-term basis. 66 individuals underwent assessment of aortic regurgitation (AR) both in CMR and TTE between August 2012 and April 2017. The follow-up rate was 76% with a median of 5.1 years. Cox proportional hazards method was used to assess the association of the time-to-aortic-valve-surgery, including valve replacement and reconstruction, and imaging parameters. A direct comparison of most predictive CMR and echocardiographic parameters was performed by using nested-factor-models. Sixteen patients (32%) were treated with aortic valve surgery during follow-up. Aortic valve insufficiency parameters, both of echocardiography and CMR, showed good discriminative and predictive power regarding the need of valve surgery. Within all examined parameters AR gradation derived by CMR correlated best with outcome [χ2 = 27.1; HR 12.2 (95% CI: 4.56, 36.8); (p < 0.0001)]. In direct comparison of both modalities, CMR assessment provided additive prognostic power beyond echocardiographic assessment of AR but not vice versa (improvement of χ2 from 21.4 to 28.4; p = 0.008). Nested model analysis demonstrated an overall better correlation with outcome by using both modalities compared with using echo alone with the best improvement in the moderate to severe AR range with an echo grade II out of III and a regurgitation fraction of 32% in CMR. This study corroborates the capability of CMR in direct quantification of AR and its role for guiding further treatment decisions particularly in patients with moderate AR in echocardiography.

Accuracy of stroke volume measurement with phase-contrast cardiovascular magnetic resonance in patients with aortic stenosis

BackgroundPhase contrast (PC) cardiovascular magnetic resonance (CMR) in the ascending aorta (AAo) is widely used to calculate left ventricular (LV) stroke volume (SV). The accuracy of PC CMR may be altered by turbulent flow. Measurement of SV at another site is suggested in the presence of aortic stenosis, but very few data validates the accuracy or inaccuracy of PC in that setting. Our objective is to compare flow measurements obtained in the AAo and LV outflow tract (LVOT) in patients with aortic stenosis.MethodsRetrospective analysis of patients with aortic stenosis who had CMR and echocardiography. Patients with mitral regurgitation were excluded. PC in the AAo and LVOT were acquired to derive SV. LV SV from end-systolic and end-diastolic tracings was used as the reference measure. A difference ≥ 10% between the volumetric method and PC derived SVs was considered discordant. Metrics of turbulence and jet eccentricity were assessed to explore the predictors of discordant measurements.ResultsWe included 88 patients, 41% with bicuspid aortic valve. LVOT SV was concordant with the volumetric method in 79 (90%) patients vs 52 (59%) patients for AAo SV (p = 0.015). In multivariate analysis, aortic stenosis flow jet angle was a strong predictor of discordant measurement in the AAo (p = 0.003). Mathematical correction for the jet angle improved the concordance from 59 to 91%. Concordance was comparable in patients with bicuspid and trileaflet valves (57% and 62% concordance respectively; p = 0.11). Accuracy of SV measured in the LVOT was not influenced by jet eccentricity. For aortic regurgitation quantification, PC in the AAo had better correlation to volumetric assessments than LVOT PC.ConclusionLVOT PC SV in patients with aortic stenosis and eccentric jet might be more accurate compared to the AAo SV. Mathematical correction for the jet angle in the AAo might be another alternative to improve accuracy.

The role of descending aorta diastolic reverse flow in the quantification of aortic regurgitation by CMR

Abstract Background EACVI recommends the use of an “integrative approach”, using several parameters, in aortic regurgitation (AR) quantification. This approach is easily achieved by echocardiography although cardiovascular magnetic resonance (CMR) remains the gold standard for the quantification of regurgitant fraction (RF). Purpose The aim of the study was to analyze the accuracy of descending aorta (DA) diastolic reverse flow in the assessment of chronic AR severity by CMR to identify an additional parameter. Methods 188 patients (34% female, 54.6±15.6 years) with different severity grades of chronic AR were enrolled. All patients underwent a CMR study. Aortic regurgitation was considered as absent (≤1%), mild (≤15%), moderate (≤15%) or severe (≥30%) depending on RF value at valve level. Furthermore, cine-sequences were used to estimate aortic diameters and distensibilities using Art Fun software. Velocity-time integral (VTI) of reverse flow in DA was calculated from maximum velocity curves by an in-house MatLab code. Results AR was absent in 21 (12%) patients, mild in 114 (62.9%), moderate in 23 (12.7%) and severe in 21 (11.6%).DA VTI reverse flow was significantly higher as was the RF at valve level (r=0.805, p&amp;lt;0.001) (IMG, Table). It also positively correlated withaortic root diameter (r=0.347, p&amp;lt;0.001) and DA distensibility (r=0.279, p&amp;lt;0.001). It did not correlate with age (r=−0.91, p=0.22). In a statistically significant multiple regression model (p&amp;lt;0.001, R2 = 0.697), although VTI reverse flow in DA correlated strongly with RF at valve level (p&amp;lt;0.001; beta = 0.733), it was also influenced by DA distensibility (p&amp;lt;0.001; beta = 0.197) and aortic root diameter (p&amp;lt;0.001; beta= 0.140). Conclusions VTI reverse flow in DA correlates strongly with the degree of AR and may be useful in the assessment of its severity. Neverthless, owing to the influence of other factors (aortic distensibility and aortic root diameter), it cannot be used as a single parameter in the quantification of AR severity by CMR. Scatter Plot graphs Funding Acknowledgement Type of funding source: Other. Main funding source(s): research grant provided by the Cardiopath PhD program

Velocity-Time Integral of Aortic Regurgitation: A Novel Echocardiographic Marker in the Evaluation of Aortic Regurgitation Severity.

ResumoFundamento A ecocardiografia é essencial para o diagnóstico e a quantificação da insuficiência aórtica (IA). A integral velocidade-tempo (IVT) do fluxo da IA pode estar relacionada à gravidade da IA.Objetivo Este estudo tem por objetivo avaliar se a IVT é um marcador ecocardiográfico de gravidade da IA.Métodos Foram incluídos todos os pacientes com IA nativa moderada ou grave e ritmo sinusal que visitaram o nosso laboratório de imagem entre janeiro e outubro de 2016. Todos os indivíduos foram submetidos a um ecocardiograma completo com medição da IVT da IA. A associação entre a IVT e a gravidade da IA foi analisada por regressão logística e modelos de regressão multivariada. Valores p<0,05 foram considerados estatisticamente significativos.Resultados Entre os 62 pacientes incluídos (68,5±14,9 anos; 64,5%: IA moderada; 35,5%: IA grave), a IVT foi maior em indivíduos com IA moderada em comparação àqueles com IA grave (2,2±0,5 m versus 1,9±0,5 m, p=0,01). Pacientes com IA grave apresentaram valores maiores de diâmetro diastólico final do ventrículo esquerdo (DDFVE) (56,1±7,1 mm versus 47,3±9,6 mm, p=0,001), volume diastólico final do ventrículo esquerdo (VDFVE) (171±36,5 mL versus 106±46,6 mL, p<0,001), orifício regurgitante efetivo (0,44±0,1 cm2 versus 0,18±0,1 cm2, p=0,002) e volume regurgitante (71,3±25,7 mL versus 42,5±10,9 mL, p=0,05), assim como menor fração de ejeção do ventrículo esquerdo (FEVE) (54,1±11,2% versus 63,2±13,3%, p=0,012). A IVT mostrou ser um marcador de gravidade da IA, independentemente do DDFVE, VDFVE e FEVE ( odds ratio 0,160, p=0,032) e da frequência cardíaca e pressão arterial diastólica (PAD) ( odds ratio 0,232, p=0,044).Conclusões A IVT do fluxo da IA apresentou associação inversa com a gravidade da IA, independentemente do diâmetro e volume do ventrículo esquerdo, frequência cardíaca, PAD e FEVE. A IVT pode ser um marcador de gravidade da IA em pacientes com IA nativa e ritmo sinusal. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0)

Proof of Concept: Echo Compatible Mock-Circulatory Flow Loop to Accurately Quantify Aortic Regurgitation in Patients with Left Ventricular Assist Devices

Aortic regurgitation (AR) in patients with Left ventricular assist devices (LVAD) is associated with poor outcome and decreased device durability. Accurate quantification of aortic regurgitation in patients with LVAD by echocardiography has been a challenge, particularly since there is no gold standard for accurate regurgitant volume estimation. Therefore, the aim of our study was to develop a mock-circulatory flow loop using patient specific 3D model that allows accurate assessment of AR by flow meters. Using a cardiac CT from a patient with LVAD and aortic regurgitation, a 3D model was printed. A pulsatile flow loop system and HeartMate II LVAD was connected to 3D model and we were able to accurately simulate LV and Aortic pressure (figure 1). Aortic regurgitant volume (RV) was quantified at various LVAD speeds. The AR volume was quantified at increments of 200 RPM. At baseline speed of 8000 RPM, the regurgitant volume was 34 cc and with each increment in speed the RV increased proportionally. This system is echo compatible and the in vitro echocardiographic evaluation of AR severity is being developed CONCLUSION: We have created patient specific model of AR in a flow system with LVAD support. Thus far we have demonstrated that RV varies directly with level of LVAD support.

Clinical use of 4D flow MRI for quantification of aortic regurgitation

ObjectiveThe main objective of the present study was to compare the use of four-dimensional (4D) flow MRI with the habitual sequence (two-dimensional phase-contrast (2DPC) MRI) for the assessment of aortic...

1051 Assessment of asymptomatic severe aortic regurgitation by doppler-derived echo indices: comparison with magnetic resonance quantification

Abstract Funding Acknowledgements This study was supported by Ministry of Health of the Czech Republic 17-28265A Introduction Management of asymptomatic patients with chronic severe aortic regurgitation (AR) is challenging. Reliable quantification of the AR severity is essential. Transthoracic echocardiography (TTE) is a primary imaging modality. Grading of AR severity is achieved by an integrative approach. Cardiovascular magnetic resonance (CMR) can directly quantify AR severity by measuring regurgitation volume (RV) and regurgitation fraction (RF). Purpose There are few data on direct comparison between TTE and CMR for quantification of AR. Our study aimed to compare quantitative and indirect echo-Doppler indices to quantitative MRI derived parameters in asymptomatic patients with severe chronic AR. Methods In a prospective three-centre study, we evaluated patients with moderate to severe (3+) and severe (4+) chronic AR using TTE and CMR. All patients were asymptomatic, without indication for surgical treatment. The severity of AR was graded using TTE multiparametric approach. A 2-D and 3-D TTE were performed with an assessment of left ventricle size and function, valve morphology, Doppler parameters of AR including vena contracta width, diastolic flow reversal velocity in descending aorta, RV, RF using volumetric method, 3D-vena contracta area (3D-VCA). The CMR quantified left ventricle volumes and function, RF and RV using the phase-contrast velocity mapping. All imaging studies were analysed in CoreLab. Results A total of 104 patients were enrolled during 2015-2018. Mean patient age was 44 ± 13 years, 89 patients (86%) were males and 83 patients (81%) had a bicuspid or unicuspid aortic valve. Using the TTE severe (4+) AR was present in 48 (46%) and moderate to severe (3+) AR in 56 (54%) individuals. Concordant grading of AR severity with both techniques was observed in 77 (74%) patients. An integrative TTE approach showed a trend to underestimate AR severity. The best correlation between echo-Doppler indices and CMR measured RV and RF was found in two parameters: diastolic flow reversal velocity in descending aorta ( Rs = 0,62, p &amp;lt; 0,0001 for RV, Rs = 0,50, p &amp;lt; 0,0001 for RF) and 3D-VCA (Rs = 0,48 for RV, p &amp;lt; 0,0001 , Rs = 0,38 for RF, p &amp;lt; 0,0001). On the contrary vena contracta width showed poor correlation with CMR (Rs = 0,18, p = 0,07 for RV and Rs = 0,11, p = 0,29 for RF). Correlation between quantitative parameters of AR assessed by TTE volumetric method and CMR technique was modest (Rs = 0,40 for RF and Rs = 0,50 for RV, p &amp;lt; 0,0001), 95% confidence intervals were wide. Good correlation between TTE and CMR were found for LV dimensions, volumes and ejection fraction. Conclusion Out of indirect Doppler-echo indices of AR severity, diastolic flow reversal velocity in descending aorta and 3D-vena contracta area showed the best correlation with MRI derived RF and RV in patients with chronic severe AR. Quantitative parameters of AR (RF and RV) assessed by echo volumetric method had an only modest correlation to RF and RV measured using CMR.

Echocardiographic Quantification of Aortic Regurgitation in Transcatheter Valves: A Need for Refinement

Echocardiographic Quantification of Aortic Regurgitation in Transcatheter Valves: A Need for Refinement

Chronic Severe Aortic Regurgitation: Should We Lower Operating Thresholds?

Chronic Severe Aortic Regurgitation: Should We Lower Operating Thresholds?

Meta-Analysis of Transthoracic Echocardiography Versus Cardiac Magnetic Resonance for the Assessment of Aortic Regurgitation After Transcatheter Aortic Valve Implantation

Residual aortic regurgitation (AR) is a major complication after transcatheter aortic valve implantation (TAVI). Although the echocardiographic assessment of post-TAVI AR remains challenging, cardiac magnetic resonance (CMR) allows direct quantification of AR. The aim of this study was to review the level of agreement between 2-dimensional transthoracic echocardiography (2D TTE) and CMR on grading the severity of AR after TAVI, and determine the accuracy of TTE in detecting moderate or severe AR. Electronic databases were searched in order to identify studies comparing 2D TTE to CMR for post-TAVI AR assessment. Kappa coefficient was used to determine the level of agreement between the 2 imaging modalities. CMR was used as the reference standard in order to assess the diagnostic accuracy of 2D TTE. Seven studies were included in this systematic review. Six studies reported a low correlation between 2D TTE and CMR (kappa coefficient ranging from -0.02 to 0.41), whereas one study showed good agreement with a kappa coefficient of 0.72. Given the heterogeneity in the included studies the diagnostic accuracy of TTE was evaluated by estimating the hierarchical summary receiver operator characteristic curve. The area under the curve for detection of moderate or severe AR with TTE was 0.83 (95% confidence interval 0.79 to 0.86). In conclusion, despite the reported significant disconcordance between TTE and CMR grading of AR, TTE has sufficient ability to discriminate moderate or severe AR from mild or none AR after TAVI in the clinical setting. CMR should be considered when TTE results are equivocal.