Hemodynamic characteristics and progression to heart failure in regurgitant lesions

The assessment of left ventricular diastolic function: guidance and recommendations from the British Society of Echocardiography

Impairment of left ventricular (LV) diastolic function is common amongst those with left heart disease and is associated with significant morbidity. Given that, in simple terms, the ventricle can only eject the volume with which it fills and that approximately one half of hospitalisations for heart failure (HF) are in those with normal/'preserved' left ventricular ejection fraction (HFpEF) (Bianco et al. in JACC Cardiovasc Imaging. 13:258-271, 2020. 10.1016/j.jcmg.2018.12.035), where abnormalities of ventricular filling are the cause of symptoms, it is clear that the assessment of left ventricular diastolic function (LVDF) is crucial for understanding global cardiac function and for identifying the wider effects of disease processes. Invasive methods of measuring LV relaxation and filling pressures are considered the gold-standard for investigating diastolic function. However, the high temporal resolution of trans-thoracic echocardiography (TTE) with widely validated and reproducible measures available at the patient's bedside and without the need for invasive procedures involving ionising radiation have established echocardiography as the primary imaging modality. The comprehensive assessment of LVDF is therefore a fundamental element of the standard TTE (Robinson et al. in Echo Res Pract7:G59-G93, 2020. 10.1530/ERP-20-0026). However, the echocardiographic assessment of diastolic function is complex. In the broadest and most basic terms, ventricular diastole comprises an early filling phase when blood is drawn, by suction, into the ventricle as it rapidly recoils and lengthens following the preceding systolic contraction and shortening. This is followed in late diastole by distension of the compliant LV when atrial contraction actively contributes to ventricular filling. When LVDF is normal, ventricular filling is achieved at low pressure both at rest and during exertion. However, this basic description merely summarises the complex physiology that enables the diastolic process and defines it according to the mechanical method by which the ventricles fill, overlooking the myocardial function, properties of chamber compliance and pressure differentials that determine the capacity for LV filling. Unlike ventricular systolic function where single parameters are utilised to define myocardial performance (LV ejection fraction (LVEF) and Global Longitudinal Strain (GLS)), the assessment of diastolic function relies on the interpretation of multiple myocardial and blood-flow velocity parameters, along with left atrial (LA) size and function, in order to diagnose the presence and degree of impairment. The echocardiographic assessment of diastolic function is therefore multifaceted and complex, requiring an algorithmic approach that incorporates parameters of myocardial relaxation/recoil, chamber compliance and function under variable loading conditions and the intra-cavity pressures under which these processes occur. This guideline outlines a structured approach to the assessment of diastolic function and includes recommendations for the assessment of LV relaxation and filling pressures. Non-routine echocardiographic measures are described alongside guidance for application in specific circumstances. Provocative methods for revealing increased filling pressure on exertion are described and novel and emerging modalities considered. For rapid access to the core recommendations of the diastolic guideline, a quick-reference guide (additional file 1) accompanies the main guideline document. This describes in very brief detail the diastolic investigation in each patient group and includes all algorithms and core reference tables.

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.

Aortic root diameter is associated with HLA-B27: identifying the patient with ankylosing spondylitis at risk for aortic valve regurgitation

To assess the association between the aortic root diameter in HLA-B27 positive (+) and HLA-B27 negative (−) ankylosing spondylitis (AS) patients from the CARDAS cohort. The CARDAS study is a cross-sectional study in AS patients between 50 and 75 years who were recruited from a large rheumatology outpatient clinic. Patients underwent cardiovascular screening including echocardiography, with 2D, spectral, and color flow Doppler measurements. The aortic root was measured at sinuses of Valsalva during diastole. The aortic root diameter was adjusted for body surface area (BSA) (aortic root index, cm/m²). 193 Consecutive AS patients were included of whom 158 (82%) were HLA-B27 positive. The aortic root index was significantly higher in HLA-B27 + patients compared to HLA-B27− patients, respectively, 1.76 cm ± 0.21 vs. 1.64 cm ± 0.14, p < 0.001. No difference was seen in the prevalence of aortic valve regurgitation (AVR), p = 0.8. Regression analysis showed a significant association between HLA-B27 and aortic root index corrected for age, sex and cardiovascular risk factors (β 0.091, 95% CI 0.015–0.168, p = 0.02). Especially, male HLA-B27 + patients had a significantly increased aortic root index compared to male HLA-B27− AS patients, respectively, 1.76 cm (1.63–1.88) and 1.59 cm (1.53–1.68), p < 0.001. We found an increased aortic root index in elderly HLA-B27 + AS patients compared to HLA-B27− AS patients, especially in male patients. No difference was seen in the prevalence of AVR. However, as AVR can be progressive, echocardiographic monitoring in elderly male HLA-B27 + AS might be considered.

Timing of Surgical Intervention for Aortic Regurgitation

OPINION STATEMENT

Aortic regurgitation is a frequently encountered condition, in which traditional measurements of severity have proven to be of limited value in identifying those who would be best served by aortic valve replacement. Novel methods of assessing severity are vital, particularly as an entirely new paradigm of aortic regurgitation has surfaced, with the advent of transcatheter aortic valve replacement (TAVR), and the adverse events that are being observed with varying degrees of aortic regurgitation. With that in mind, a comprehensive assessment of aortic regurgitation should now include indexed left ventricular systolic volumes and a comprehensive assessment of right ventricular function, in addition to the quantitative measures that are currently recommended. Cardiac MRI also provides valuable information and should be strongly considered, particularly in challenging cases. The incremental value of additional echocardiographic parameters such as strain imaging, speckle tracking imaging, and tissue Doppler imaging remains unclear, and evidence for their utility is not, as yet, compelling. However, the field of aortic regurgitation assessment has been reinvigorated by the prevalence of paravalvular regurgitation post-TAVR, and many of the abovementioned parameters may need to be re-visited so that we can more accurately determine prognosis and risk stratify patients in a more reliable and evidence-based manner.

Imaging Aortic Regurgitation: The Incremental Benefit of Speckle Tracking Echocardiography

Aortic regurgitation (AR) affects global left ventricular mechanics. However, limited literature is available on how it may affect regional longitudinal strain.

We present a case where severe AR jet is thrashing the anterior-septal wall and reducing its overall longitudinal performance most likely secondary to increased wall shear stress in diastole. This new insight into patho-physiological process using deformation study may have supplementary impact in decision making for surgical intervention. Transthoracic echocardiography is the primary imaging modality for the assessment of AR as it offers evaluation of severity of AR, aetiology of AR, left ventricular (LV) dilatation, LV systolic function, left ventricular mass, diastolic function and global strain. This case highlights the regional disturbances in longitudinal strain in eccentric AR.

Development of a consensus document to improve multireader concordance and accuracy of aortic regurgitation severity grading by echocardiography versus cardiac magnetic resonance imaging

Current guidelines recommend a multiparametric echocardiographic assessment of aortic regurgitation (AR). However, the absence of a hierarchical weighting of discordant parameters could cause interobserver variability. In the present study, we sought to define and improve the interobserver variability of AR assessment. Seventeen level 3 readers graded 20 randomly selected patients with AR. The readers also provided a usefulness score for each parameter, depending on its influence on their decision of the AR severity grade. A consensus strategy was subsequently formulated and validated against cardiac magnetic resonance imaging in a separate group of 80 patients. The readers were updated with the consensus document and recalibrated using the same cases. Agreement was statistically assessed using Randolph's free-marginal multirater kappa. At baseline, no uniform approach was used to combine the individual parameters, contributing to the interobserver variability (overall kappa 0.5). A consensus strategy to categorize AR severity was developed in which the left ventricular volume took precedence over the other parameters and was used to differentiate chronic severe AR from less severe categories. Recalibration of the readers using this consensus strategy improved concordance (kappa increased to 0.7). The new strategy also improved the accuracy relative to cardiac magnetic resonance imaging, as evidenced by full agreement on severe AR between the consensus document-based grading and AR severity defined by cardiac magnetic resonance imaging in the separate validation group of 80 patients. In conclusion, grading of chronic AR using a multiparametric approach has suboptimal consistency between readers and a left ventricular volume-based consensus document improved concordance and accuracy.

Valvular heart disease: diagnosis and management

Valvular heart disease (VHD) encompasses a number of common cardiovascular conditions that account for 10% to 20% of all cardiac surgical procedures in the United States. A better understanding of the natural history coupled with the major advances in diagnostic imaging, interventional cardiology, and surgical approaches have resulted in accurate diagnosis and appropriate selection of patients for therapeutic interventions. A thorough understanding of the various valvular disorders is important to aid in the management of patients with VHD. Appropriate work-up for patients with VHD includes a thorough history for evaluation of causes and symptoms, accurate assessment of the severity of the valvular abnormality by examination, appropriate diagnostic testing, and accurate quantification of the severity of valve dysfunction and therapeutic interventions, if necessary. It is also important to understand the role of the therapeutic interventions vs the natural history of the disease in the assessment of outcomes. Prophylaxis for infective endocarditis is no longer recommended unless the patient has a history of endocarditis or a prosthetic valve.