2014 AHA/ACC guideline for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines

Moderate aortic stenosis: Navigating the uncharted

Aortic stenosis (AS) stands as the most common valvular heart disease in developed countries and is characterized by progressive narrowing of the aortic valve orifice resulting in elevated transvalvular flow resistance, left ventricular hypertrophy, and progressive increased risk of heart failure and sudden death. This narrative review explores clinical challenges and evolving perspectives in moderate AS, where discrepancies between aortic valve area and pressure gradient measurements may pose diagnostic and therapeutic quandaries. Transthoracic echocardiography is the first-line imaging modality for AS evaluation, yet cases of discordance may require the application of ancillary noninvasive diagnostic modalities. This review underscores the importance of accurate grading of AS severity, especially in low-gradient phenotypes, emphasizing the need for vigilant follow-up. Current clinical guidelines primarily recommend aortic valve replacement for severe AS, potentially overlooking latent risks in moderate disease stages. The noninvasive multimodality imaging approach-including echocardiography, cardiac magnetic resonance, computed tomography, and nuclear techniques-provides unique insights into adaptive and maladaptive cardiac remodeling in AS and offers a promising avenue to deliver precise indications and exact timing for intervention in moderate AS phenotypes and asymptomatic patients, potentially improving long-term outcomes. Nevertheless, what we may have gleaned from a large amount of observational data is still insufficient to build a robust framework for clinical decision-making in moderate AS. Future research will prioritize randomized clinical trials designed to weigh the benefits and risks of preemptive aortic valve replacement in the management of moderate AS, as directed by specific imaging and nonimaging biomarkers.

Echocardiographic Evaluation of Aortic Stenosis: A Comprehensive Review

Echocardiography represents the most important diagnostic tool in the evaluation of aortic stenosis. The echocardiographic assessment of its severity should always be performed through a standardized and stepwise approach in order to achieve a comprehensive evaluation. The latest technical innovations in the field of echocardiography have improved diagnostic accuracy, guaranteeing a better and more detailed evaluation of aortic valve anatomy. An early diagnosis is of utmost importance since it shortens treatment delays and improves patient outcomes. Echocardiography plays a key role also in the evaluation of all the structural changes related to aortic stenosis. Detailed evaluation of subtle and subclinical changes in left ventricle function has a prognostic significance: scientific efforts have been addressed to identify the most accurate global longitudinal strain cut-off value able to predict adverse outcomes. Moreover, in recent years the role of artificial intelligence is increasingly emerging as a promising tool able to assist cardiologists in aortic stenosis screening and diagnosis, especially by reducing the rate of aortic stenosis misdiagnosis.

Cardiovascular positron emission tomography: established and emerging role in cardiovascular diseases

Cardiac positron emission tomography (PET) imaging has established themselves firmly as excellent and reliable functional imaging modalities in assessment of the spectrum of coronary artery disease. With the explosion of technology advances and the dream of flow quantification now a reality, the value of PET is now well realized. Cardiac PET has proved itself as precise imaging modality that provides functional imaging of the heart in addition to anatomical imaging. It has established itself as one of the best available techniques for evaluation of myocardial viability. Hybrid PET/computed tomography provides simultaneous integration of coronary anatomy and function with myocardial perfusion and metabolism, thereby improving characterization of the dysfunctional area and chronic coronary artery disease. The availability of quantitative myocardial blood flow evaluation with PET provides additional prognostic information and increases diagnostic accuracy in the management of patients with coronary artery disease. Hybrid imaging seems to hold immense potential in optimizing management of cardiovascular diseases and furthering clinical research.

Molecular Approaches and Echocardiographic Deformation Imaging in Detecting Myocardial Fibrosis

The pathological remodeling of myocardial tissue is the main cause of heart diseases. Several processes are involved in the onset of heart failure, and the comprehension of the mechanisms underlying the pathological phenotype deserves special attention to find novel procedures to identify the site of injury and develop novel strategies, as well as molecular druggable pathways, to counteract the high degree of morbidity associated with it. Myocardial fibrosis (MF) is recognized as a critical trigger for disruption of heart functionality due to the excessive accumulation of extracellular matrix proteins, in response to an injury. Its diagnosis remains focalized on invasive techniques, such as endomyocardial biopsy (EMB), or may be noninvasively detected by cardiac magnetic resonance imaging (CMRI). The detection of MF by non-canonical markers remains a challenge in clinical practice. During the last two decades, two-dimensional (2D) speckle tracking echocardiography (STE) has emerged as a new non-invasive imaging modality, able to detect myocardial tissue abnormalities without specifying the causes of the underlying histopathological changes. In this review, we highlighted the clinical utility of 2D-STE deformation imaging for tissue characterization, and its main technical limitations and criticisms. Moreover, we focalized on the importance of coupling 2D-STE examination with the molecular approaches in the clinical decision-making processes, in particular when the 2D-STE does not reflect myocardial dysfunction directly. We also attempted to examine the roles of epigenetic markers of MF and hypothesized microRNA-based mechanisms aiming to understand how they match with the clinical utility of echocardiographic deformation imaging for tissue characterization and MF assessment.

Comparison of Simultaneous Transthoracic Versus Transesophageal Echocardiography for Assessment of Aortic Stenosis

Transthoracic echocardiography (TTE) is the gold standard for aortic stenosis (AS) assessment. Transesophageal echocardiography (TEE) provides better resolution, but its effect on AS assessment is unclear. To answer this question, we studied 56 patients with ≥moderate AS. Initial TTE (TTE1) was followed by conscious sedation with simultaneous TEE and TTE2. Based on conservative versus actionable implication, AS types were dichotomized into group A, comprising moderate and normal-flow low-gradient, and group B, comprising high gradient, low ejection fraction low-flow low-gradient, and paradoxical low-flow low-gradient AS. Paired analysis of echocardiographic variables and AS types measured by TEE versus TTE2 and by TEE versus TTE1 was performed. TEE versus simultaneous TTE2 comparison demonstrated higher mean gradients (31.7 ± 10.5 vs 27.4 ± 10.5 mm Hg) and velocities (359 ± 60.6 vs 332 ± 63.1 cm/s) with TEE, but lower left ventricular outflow velocity-time-integral (VTI₁) (18.6 ± 5.1 vs 20.2 ± 6.1 cm), all p <0.001. This resulted in a lower aortic valve area (0.8 ± 0.21 vs 0.87 ± 0.28 cm²), p <0.001, and a net relative risk of 1.86 of group A to B upgrade. TEE versus (awake state) TTE1 comparison revealed a larger decrease in VTI₁ because of a higher initial awake state VTI₁ (22 ± 5.6 cm), resulting in similar Doppler-velocity-index and aortic valve area decrease with TEE, despite a slight increase in mean gradients of 0.8 mm Hg (confidence interval -1.44 to 3.04) and velocities of 10 cm/s (confidence interval -1.5 to 23.4). This translated into a net relative risk of 1.92 of group A to B upgrade versus TTE1. In conclusion, TEE under conscious sedation overestimates AS severity compared with both awake state TTE and simultaneous sedation state TTE, accounted for by different Doppler insonation angles obtained in transapical versus transgastric position.

Sex Differences in Factors Associated With Progression of Aortic Valve Calcification in the General Population

BACKGROUND

Guidelines recommend measurement of the aortic valve calcification (AVC) score to help differentiate between severe and nonsevere aortic stenosis, but a paucity exists in data about AVC in the general population. The aim of this study was to describe the natural history of AVC progression in the general population and to identify potential sex differences in factors associated with this progression rate.

METHODS

Noncontrast cardiac computed tomography was performed in 1298 randomly selected women and men aged 65 to 74 years who participated in the DANCAVAS trial (Danish Cardiovascular Screening). Participants were invited to attend a reexamination after 4 years. The AVC score was measured at the computed tomography, and AVC progression (ΔAVC) was defined as the difference between AVC scores at baseline and follow-up. Multivariable regression analyses were performed to identify factors associated with ΔAVC.

RESULTS

Among the 1298 invited citizens, 823 accepted to participate in the follow-up examination. The mean age at follow-up was 73 years. Men had significantly higher AVC scores at baseline (median AVC score 13 Agatston Units [AU; interquartile range, 0-94 AU] versus 1 AU [interquartile range, 0-22 AU], P<0.001) and a higher ΔAVC (median 26 AU [interquartile range, 0-101 AU] versus 4 AU [interquartile range, 0-37 AU], P<0.001) than women. In the fully adjusted model, the most important factor associated with ΔAVC was the baseline AVC score. However, hypertension was associated with ΔAVC in women (incidence rate ratios, 1.58 [95% CI, 1.06-2.34], P=0.024) but not in men, whereas dyslipidemia was associated with ΔAVC in men (incidence rate ratio: 1.66 [95% CI, 1.18-2.34], P=0.004) but not in women.

CONCLUSIONS

The magnitude of the AVC score was the most important marker of AVC progression. However, sex differences were significant; hence, dyslipidemia was associated with AVC progression only among men; hypertension with AVC progression only among women. Registration: URL: https://www.isrctn.com; Unique identifier: ISRCTN12157806.

Subclinical Ventricular Dysfunction in Long-Term Acromegaly Assessed by Speckle-Tracking Echocardiography

INTRODUCTION

Symptomatic heart disease may be present in patients with advanced-stage acromegaly. However, earlier assessment of subclinical ventricular systolic dysfunction can be accomplished through speckle-tracking echocardiography (STE) for the study of myocardial strain. The few such studies in this population to date have produced conflicting results. This study was performed to evaluate the parameters of ventricular strain in patients with acromegaly with no cardiac symptoms.

METHODS

In this prospective observational study, STE was performed in patients with active acromegaly with no detectable heart disease and in a control group to assess ventricular dysfunction through global longitudinal strain (GLS), radial strain, circumferential strain, and twist. The left ventricular (LV) ejection fraction, LV mass index, and relative wall thickness were also compared between the groups.

RESULTS

Twenty-five patients with active acromegaly (median age, 49 years; median disease duration, 11 years) and 44 controls were included. LV hypertrophy was more prevalent in the acromegaly group (40% vs. 19%, p < 0.01). The LV ejection fraction was similar between the groups (65.2% ± 5.99% vs. 62.9% ± 7.41%). The mean GLS (-18.8 ± 2.49 vs. -19.7 ± 3.29, p = 0.24), circumferential strain (-16.7 ± 3.18 vs. -16.6 ± 3.42, p = 0.90), and twist (14.6 ± 5.02 vs. 15.1 ± 3.94, p = 0.60) were not significantly different between the groups.

CONCLUSION

Despite showing higher rates of LV hypertrophy, patients with long-term acromegaly had no impairment of ventricular contractility as assessed by strain echocardiography when compared with a control group.

Severe aortic stenosis echocardiographic thresholds revisited

BACKGROUND

In view of inconsistencies in threshold values of severe aortic stenosis (AS) hemodynamic indices, it is unclear what is the relative contribution of each variable in a binary classification of AS based on aortic valve replacement (AVR) indication. We aimed to assess relative discriminative value and optimal threshold of each constituent hemodynamic parameter for this classification and confirm additional prognostic value.

METHODS

Echocardiography studies of 168 patients with ≥ moderate AS were included. AS types were dichotomized into Group-A, comprising moderate and Normal-Flow Low-Gradient (NFLG), and Group-B, comprising High-Gradient(HG), Low Ejection Fraction Low-Flow Low-Gradient(Low EF-LFLG), and Paradoxical Low-Flow Low-Gradient(PLFLG) AS. Aortic valve area (AVA), Doppler velocity index (DVI), peak aortic velocity, mean gradient, stroke volume index and transaortic flow rate(TFR) were assessed for A/B Group discrimination value and optimal thresholds were determined. Dichotomized values were assessed for predictive value for AVR or death.

RESULTS

C-statistic values for binary AS classification was .74-.9 for the tested variables. AVA and DVI featured the highest score, and SVI the lowest one. AVA≤.81 cm² and DVI≤.249 had 87.6% and 86% respective sensitivity for Group B patients, and a similar specificity of 80.9%. During a mean follow-up of 9.1±10.1 months, each of the tested dichotomized variables except for SVI predicted AVR or death on multivariate analysis.

CONCLUSION

An AVA value ≤.81 cm² or a DVI ≤ .249 threshold carry the highest discriminative value for severe AS in patients with aortic stenosis, translating into an independent prognostic value, and can be helpful in making clinical decisions.

Sex differences in aortic valve calcification in severe aortic valve stenosis: association between computer tomography assessed calcification and valvular calcium concentrations

AIMS

The aims of this study were to investigate the correlation and sex differences between total valve calcium, valve calcium concentration, and aortic valve calcification (AVC) in explanted valves from patients with severe aortic valve stenosis undergoing aortic valve replacement (AVR).

METHODS AND RESULTS

Sixty-nine patients with severe aortic stenosis (AS) scheduled for elective AVR underwent echocardiography and cardiac computed tomography (CT) prior to surgery (AVCin vivo) and CT of the explanted aortic valve (AVCex vivo). Explanted valves were prepared in acid solution, sonicated, and analysed with Arsenazo III dye to estimate total valve calcium and valve calcium concentration. Median AVCex vivo was 2082 (1421-2973) AU; mean valve calcium concentration was 1.43 ± 0.42 µmol Ca2+/mg tissue; median total valve calcium 156 (111-255) mg Ca2+, and valve calcium density 52 (35-81) mg/cm2. AVC displayed a strong correlation with total valve calcium (R2 = 0.98, P < 0.001) and a moderate correlation with valve calcium concentration (R2 = 0.62, P < 0.001). Valvular calcium concentration was associated with sex, aortic valve area, and mean gradient. After adjusting for age and estimated glomerular filtration rate, sex and mean gradient remained associated with valve calcium concentrations.

CONCLUSION

AVC score provides a strong estimate for total valve calcium but to a lesser degree calcium concentration in the valve tissue of patients with severe AS. Females presented lower valvular calcium concentrations than males irrespective of AS severity, adding evidence and providing support to the important point that sex differences in valvular calcium concentration in AS does not reflect valvular size.

Correlation between non-invasive myocardial work indices and main parameters of systolic and diastolic function: results from the EACVI NORRE study

AIMS

The present study sought to evaluate the correlation between indices of non-invasive myocardial work (MW) and left ventricle (LV) size, traditional and advanced parameters of LV systolic and diastolic function by 2D echocardiography (2DE).

METHODS AND RESULTS

A total of 226 (85 men, mean age: 45 ± 13 years) healthy subjects were enrolled at 22 collaborating institutions of the Normal Reference Ranges for Echocardiography (NORRE) study. Global work index (GWI), global constructive work (GCW), global work waste (GWW), and global work efficiency (GWE) were estimated from LV pressure-strain loops using custom software. Peak LV pressure was estimated non-invasively from brachial artery cuff pressure. LV size, parameters of systolic and diastolic function and ventricular-arterial coupling were measured by echocardiography. As advanced indices of myocardial performance, global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) were obtained. On multivariable analysis, GWI was significantly correlated with GLS (standardized beta-coefficient = -0.23, P < 0.001), ejection fraction (EF) (standardized beta-coefficient = 0.15, P = 0.02), systolic blood pressure (SBP) (standardized beta-coefficient = 0.56, P < 0.001) and GRS (standardized beta-coefficient = 0.19, P = 0.004), while GCW was correlated with GLS (standardized beta-coefficient = -0.55, P < 0.001), SBP (standardized beta-coefficient = 0.71, P < 0.001), GRS (standardized beta-coefficient = 0.11, P = 0.02), and GCS (standardized beta-coefficient = -0.10, P = 0.01). GWE was directly correlated with EF and inversely correlated with Tei index (standardized beta-coefficient = 0.18, P = 0.009 and standardized beta-coefficient = -0.20, P = 0.004, respectively), the opposite occurred for GWW (standardized beta-coefficient =--0.14, P = 0.03 and standardized beta-coefficient = 0.17, P = 0.01, respectively).

CONCLUSION

The non-invasive MW indices show a good correlation with traditional 2DE parameters of myocardial systolic function and myocardial strain.

Discordant Echocardiographic Grading in Low Gradient Aortic Stenosis (DEGAS Study) From the Italian Society of Echocardiography and Cardiovascular Imaging Research Network: Rationale and Study Design

Background

Low-gradient aortic stenosis (LG-AS) is characterized by the combination of an aortic valve area compatible with severe stenosis and a low transvalvular mean gradient with low-flow state (i.e., indexed stroke volume <35 mL/m²) in the presence of reduced (classical low-flow AS) or preserved (paradoxical low-flow AS) ejection fraction. Furthermore, the occurrence of a normal-flow LG-AS is still advocated by many authors. Within this diagnostic complexity, the diagnosis of severe AS remains challenging.

Objective

The general objective of the Discordant Echocardiographic Grading in Low-gradient AS (DEGAS Study) study will be to assess the prevalence of true severe AS in this population and validate new parameters to improve the assessment and the clinical decision-making in patients with LG-AS.

Methods and Analyses

The DEGAS Study of the Italian Society of Echocardiography and Cardiovascular Imaging is a prospective, multicenter, observational diagnostic study that will enroll consecutively adult patients with LG-AS over 2 years. AS severity will be ideally confirmed by a multimodality approach, but only the quantification of calcium score by multidetector computed tomography will be mandatory. The primary clinical outcome variable will be 12-month all-cause mortality. The secondary outcome variables will be (i) 30-day mortality (for patients treated by Surgical aortic valve replacement or TAVR); (ii) 12-month cardiovascular mortality; (iii) 12-month new major cardiovascular events such as myocardial infarction, stroke, vascular complications, and rehospitalization for heart failure; and (iv) composite endpoint of cardiovascular mortality and hospitalization for heart failure. Data collection will take place through a web platform (REDCap), absolutely secure based on current standards concerning the ethical requirements and data integrity.

Application of strain echocardiography in valvular heart diseases

Echocardiographic strain imaging allows new insight into a complex cardiac mechanics and enables more precise evaluation of cardiac function. Hence, it has been shown to have clinical utility in a variety of valvular heart diseases. In particular, global longitudinal strain has been shown to be more sensitive to detect systolic dysfunction than left ventricular ejection fraction. In patients with valvular heart diseases, it provides both diagnostic and prognostic information in addition to standard echocardiographic and clinical parameters. In this review, we summarize current clinical application of strain echocardiography in patients with valvular heart diseases and discuss pathophysiological mechanisms that lead to respective findings in specific diseases.

Heart Valve Clinics, Centers, and Networks

There is consensus on important aspects of managing heart valve disease. Despite this, many patients are managed by general physicians or cardiologists without specialist competencies in valve disease, which leads to suboptimal outcomes. Multidisciplinary heart valve clinics bring together cardiologists, surgeons, nurses, and in some countries scientists to deliver expert guidelines and experience-driven optimal care. Patients are referred at the optimal time for interventions at heart valve centers, defined by strict standards of facilities and processes. Valve networks link valve clinic, heart valve center, and the community to improve the passage of patients at every level of care.

Outcomes of Patients With Asymptomatic Aortic Stenosis Followed Up in Heart Valve Clinics

Importance

The natural history and the management of patients with asymptomatic aortic stenosis (AS) have not been fully examined in the current era.

Objective

To determine the clinical outcomes of patients with asymptomatic AS using data from the Heart Valve Clinic International Database.

Design, Setting, and Participants

This registry was assembled by merging data from prospectively gathered institutional databases from 10 heart valve clinics in Europe, Canada, and the United States. Asymptomatic patients with an aortic valve area of 1.5 cm2 or less and preserved left ventricular ejection fraction (LVEF) greater than 50% at entry were considered for the present analysis. Data were collected from January 2001 to December 2014, and data were analyzed from January 2017 to July 2018.

Main Outcomes and Measures

Natural history, need for aortic valve replacement (AVR), and survival of asymptomatic patients with moderate or severe AS at entry followed up in a heart valve clinic. Indications for AVR were based on current guideline recommendations.

Results

Of the 1375 patients included in this analysis, 834 (60.7%) were male, and the mean (SD) age was 71 (13) years. A total of 861 patients (62.6%) had severe AS (aortic valve area less than 1.0 cm2). The mean (SD) overall survival during medical management (mean [SD] follow up, 27 [24] months) was 93% (1%), 86% (2%), and 75% (4%) at 2, 4, and 8 years, respectively. A total of 104 patients (7.6%) died under observation, including 57 patients (54.8%) from cardiovascular causes. The crude rate of sudden death was 0.65% over the duration of the study. A total of 542 patients (39.4%) underwent AVR, including 388 patients (71.6%) with severe AS at study entry and 154 (28.4%) with moderate AS at entry who progressed to severe AS. Those with severe AS at entry who underwent AVR did so at a mean (SD) of 14.4 (16.6) months and a median of 8.7 months. The mean (SD) 2-year and 4-year AVR-free survival rates for asymptomatic patients with severe AS at baseline were 54% (2%) and 32% (3%), respectively. In those undergoing AVR, the 30-day postprocedural mortality was 0.9%. In patients with severe AS at entry, peak aortic jet velocity (greater than 5 m/s) and LVEF (less than 60%) were associated with all-cause and cardiovascular mortality without AVR; these factors were also associated with postprocedural mortality in those patients with severe AS at baseline who underwent AVR (surgical AVR in 310 patients; transcatheter AVR in 78 patients).

Conclusions and Relevance

In patients with asymptomatic AS followed up in heart valve centers, the risk of sudden death is low, and rates of overall survival are similar to those reported from previous series. Patients with severe AS at baseline and peak aortic jet velocity of 5.0 m/s or greater or LVEF less than 60% have increased risks of all-cause and cardiovascular mortality even after AVR. The potential benefit of early intervention should be considered in these high-risk patients.

Multimodality Imaging for the Assessment of Severe Aortic Stenosis

Aortic stenosis is the most common type of valvular heart disease. Aortic stenosis is characterized both by progressive valve narrowing and the left ventricular remodeling response that ensues. In aortic stenosis, therapeutic decision essentially depends on symptomatic status, stenosis severity, and status of left ventricular systolic function. Imaging is fundamental for the initial diagnostic work-up, follow-up, and selection of the optimal timing and type of intervention. Noninvasive imaging has played a pivotal role in enhancing our understanding of the complex pathophysiology underlying aortic stenosis, as well as disease progression in both the valve and myocardium. The present review provides the application of multimodality imaging in aortic stenosis.

Impact of aortic stenosis on layer-specific longitudinal strain: relationship with symptoms and outcome

Aims

The present study sought to assess the impact of aortic stenosis (AS) on myocardial function as assessed by layer-specific longitudinal strain (LS) and its relationship with symptoms and outcome.

Methods and results

We compared 211 patients (56% males, mean age 73 ± 12 years) with severe AS and left ventricular ejection fraction (LVEF) ≥50% (114 symptomatic, 97 asymptomatic) with 50 controls matched for age and sex. LS was assessed from endocardium, mid-myocardium, and epicardium by 2D speckle-tracking echocardiography. Despite similar LVEF, multilayer strain values were significantly lower in symptomatic patients, compared to asymptomatic and controls [global LS: 17.9 ± 3.4 vs. 19.1 ± 3.1 vs. 20.7 ± 2.1%; endocardial LS: 20.1 ± 4.9 vs. 21.7 ± 4.2 vs. 23.4 ± 2.5%; epicardial LS: 15.8 ± 3.1 vs. 16.8 ± 2.8 vs. 18.3 ± 1.8%; P < 0.001 for all]. On multivariable logistic regression analysis, endocardial LS was independently associated to symptoms (P = 0.012), together with indexed left atrial volume (P = 0.006) and LV concentric remodelling (P = 0.044). During a mean follow-up of 22 months, 33 patients died of a cardiovascular event. On multivariable Cox-regression analysis, age (P = 0.029), brain natriuretic peptide values (P = 0.003), LV mass index (P = 0.0065), LV end-systolic volume (P = 0.012), and endocardial LS (P = 0.0057) emerged as independently associated with cardiovascular death. The best endocardial LS values associated with outcome was 20.6% (sensitivity 70%, specificity 52%, area under the curve = 0.626, P = 0.022). Endocardial LS (19.1 ± 3.3 vs. 20.7 ± 3.3, P = 0.02) but not epicardial LS (15.2 ± 2.8 vs. 15.9 ± 2.5, P = 0.104) also predicted the outcome in patients who were initially asymptomatic.

Conclusion

In patients with severe AS, LS impairment involves all myocardial layers and is more prominent in the advanced phases of the disease, when the symptoms occur. In this setting, the endocardial LS is independently associated with symptoms and patient outcome.

Aortic roots assessment by an automated three-dimensional transesophageal echocardiography: an intra-individual comparison

To evaluate the accuracy, reproducibility, and transcatheter heart valve (THV) sizing efficiency of an automated 3-dimensional transesophageal echocardiographic (3D-TEE) post-processing software in the assessments of aortic roots, intra-individually compared with multidetector computed tomography (MDCT). We prospectively studied 67 patients with normal aortic roots. We measured diameters of aortic annulus (AA), sinus of Valsalva (SOV), and sino-tubular junction (STJ) by full-automated and semi-automated methods using 3D-TEE datasets, then compared them to corresponding transthoracic echocardiography and MDCT values. THV sizes were chosen based on echocardiography and MDCT measurements according to recommended criterion. Taking MDCT planimetered diameters as reference, the full-automated (r: 0.4745-0.8792) and semi-automated (r: 0.6647-0.8805) 3D-TEE measurements were linearly correlated (p < 0.0001). The average differences between semi-automated or full-automated measurements and reference were 0.3 mm or 1.3 mm for AA, - 1.9 mm or - 0.5 mm for SOV, and - 0.1 mm or 1.9 mm for STJ, respectively. The intra-class correlation coefficients of semi-automated method were 0.79-0.96 (intra-observer) and 0.75-0.92 (inter-observer). THV sizing by semi-automated measurements using echocardiographic criteria was larger than that by MDCT measurements using MDCT criteria (p < 0.0001) but equivalent (p > 0.05) if both using MDCT standards. The new automated 3D-TEE software allows modeling and quantifying aortic roots with high reproducibility. Measurements by the semi-automated method closely approximate and well correlate with the corresponding MDCT, thus THV sizing by this modeled 3D-TEE measurements should adopt recommended MDCT criteria but not echocardiographic criteria. The full-automated 3D-TEE segmentations are yet immature. (Semi-automated assessMent of Aortic Roots by Three-dimensional transEsophageal echocaRdiography [SMARTER], NCT02724709).

Echocardiographic Assessment of Aortic Stenosis under Sedation Underestimates Stenosis Severity

BACKGROUND

Sedation can impact aortic stenosis (AS) classification, which depends on left ventricular ejection fraction (<≥ [less than or greater than and/or equal to] 50%), aortic valve area (AVA<≥ 1 cm²), mean pressure gradient (<≥ 40 mm Hg), peak velocity <≥ 400 cm/sec, and stroke volume index (SVI <≥35 mL/m²). We compared AS classification by transthoracic echo (TTE) during wakefulness versus sedation.

METHODS

Immediately following a baseline TTE performed during wakefulness, another TTE was done during sedation delivered for a concomitant transesophageal study in 69 consecutive patients with AS (mean age 78 ± 7 years, 32 males). AVA was calculated through the continuity equation using the relevant hemodynamic parameters measured by each TTE study and same left ventricular outflow tract. AS class was defined as moderate, severe high gradient (HG), low ejection fraction low flow low gradient (LF-LG), paradoxical LF-LG (PLFLG), and normal flow low gradient (NF-LG). Based on conservative versus invasive treatment implication, AS classes were aggregated into group A (moderate AS and NFLG) and group B (HG, low-EF LF-LG, and PLFLG).

RESULTS

During sedation, systolic and diastolic blood pressure decreased by 14.3 ± 29 and 8 ± 22 mm Hg, respectively, mean pressure gradient from 30.4 ± 10.9 to 27.2 ± 10.8 mm Hg, peak velocity from 345.3 ± 57.7 to 329.3 ± 64.8 cm/m², and SVI from 41.5 ± 11.3 to 38.3 ± 11.8 mL/m² (all P < .05). Calculated AVA was similar (delta = -0.009 ± 0.15 cm²). Individual discrepancies in hemodynamic parameters between the paired TTE studies resulted in an overall 17.4% rate of AS intergroup misclassification with sedation, with a relative risk of 1.09 of downgrade misclassification from group B to A versus upgrade misclassification (P < .001).

CONCLUSIONS

Sedation TTE assessment downgrades AS severity in a significant proportion of patients, with a conversely smaller proportion of patients being upgraded, and therefore cannot be a substitute for wakefulness assessment.

Imaging of Myocardial Fibrosis and Its Functional Correlates in Aortic Stenosis: A Review and Clinical Potential

Patients with severe aortic stenosis (AS) show progressive fibrotic changes in the myocardium, which may impair cardiac function and patient outcomes even after successful aortic valve replacement. Detection of patients who need an early operation remains a diagnostic challenge as myocardial functional changes may be subtle. In recent years, speckle tracking echocardiography (STE) and cardiac magnetic resonance mapping have been shown to provide complementary information for the assessment of left ventricular mechanics and identification of subtle damage by focal or diffuse myocardial fibrosis, respectively. Little is known, however, about how focal and diffuse myocardial fibrosis occurring in severe AS are related to measurable functional changes by echocardiography and to which extent both parameters have prognostic and diagnostic value. The aims of this review are to discuss the occurrence of focal and diffuse myocardial fibrosis in patients with severe AS and to explore their relation with myocardial function, determined by STE, as well as the prognostic and diagnostic potential of both parameters.

Ten Years of 2D Longitudinal Strain for Early Myocardial Dysfunction Detection: A Clinical Overview

In recent years, the role of left ventricular ejection fraction (EF) as the gold standard parameter for the evaluation of systolic function has been questioned, and many efforts have been concentrated in the clinical validation of new noninvasive tools for the study of myocardial contractility. Improvement in the accuracy of speckle-tracking echocardiography has resulted in a large amount of research showing the ability of two-dimensional strain to overcome EF limitations in the majority of primary and secondary heart diseases. Currently, global longitudinal strain (GLS) is considered the most accurate and sensitive parameter for the assessment of early left ventricular dysfunction. This review summarizes the advantages that this measurement can provide in several clinical settings. Moreover, the important cautions that should be considered in making the choice to use GLS also are addressed. Finally, a special focus on bull's-eye polar maps for the assessment of regional changes of longitudinal function and the usefulness of these maps in the differential diagnosis of several diseases is provided.

Predicting Disease Progression and Mortality in Aortic Stenosis: A Systematic Review of Imaging Biomarkers and Meta-Analysis

Background: Detecting among patients with aortic stenosis (AS) those who are likely to rapidly progress, yet potentially benefiting from prophylactic aortic valve replacement, is needed for improved patient care. The objective of this study was to evaluate the role of imaging biomarkers in predicting the progression to clinical symptoms and death in patients with AS. Methods: We searched the Pubmed and the International Clinical Trials Registry Platform databases for studies including patients with AS, and investigating imaging techniques, published in any language until Jan 1, 2018. Eligible sets of data include effect of imaging biomarkers relative to: (1) Overall mortality, (2) Cardiac mortality, and (3) Overall events (Symptom onset and Major Adverse Cardiovascular Events). Meta-analysis was used to examine associations between the imaging biomarkers and outcomes of AS using Random Effect models. Results: Eight studies and 1,639 patients were included after systematic review. Four studies investigated aortic valve calcification (AVC) whereas the remaining investigated biomarkers provided by cardiac magnetic resonance (CMR). Four articles investigated the presence of midwall fibrosis on late-gadolinium enhancement imaging, three reported its extent (LGE%) and two, the myocardial extracellular volume (ECV). By decreasing strength of association, there were significant associations between cardiac mortality and LGE% [Relative Risk (RR) = 1.05, 95% Confidence Interval (CI) 1.01-1.10]; overall mortality and AVC (RR = 1.19, 95%CI: 1.05-1.36); overall events and ECV (RR = 1.68, 95%CI: 1.17-2.41); cardiac mortality and midwall fibrosis (RR = 2.88, 95%CI: 1.12-7.39). Conclusion: AVC and myocardial fibrosis imaging biomarkers predict the outcomes in AS, and help understanding AS pathophysiology and setting therapeutic targets.

Sex-Specific Considerations in Women with Aortic Stenosis and Outcomes After Transcatheter Aortic Valve Replacement

Aortic stenosis (AS) is the most common valvular disease in the elderly and is associated with poor outcomes. Transcatheter aortic valve replacement (TAVR) is an alternative to surgical aortic valve replacement (SAVR) in high-risk patients. Herein, we describe the gender-related differences in baseline characteristics and pathophysiologic response to severe AS, imaging considerations unique to females, and short- and long-term outcomes after TAVR. Women undergoing TAVR are older and frailer, have less cardiovascular comorbidities, smaller femoral artery size, better left ventricular systolic function, hypertrophied and small left ventricles leading to a higher incidence of paradoxical low-flow low-gradient AS, and a greater prevalence of porcelain aorta, smaller aortic annulus size, and lower coronary ostia heights. Imaging and histopathological data also suggests a sex-related myocardial response to pressure overload from AS. Women experience more vascular complications and blood transfusion requirements, serious procedural complications, and a greater incidence of stroke, but have better long-term outcomes than men. Patient-prosthesis mismatch, which is a concern in patients with a small aortic annulus size undergoing SAVR, has not been problematic with TAVR. The aforementioned findings suggest that TAVR may be preferable for women with severe AS. Further studies are warranted to directly compare TAVR with SAVR in women.

Valve Calcification in Aortic Stenosis: Etiology and Diagnostic Imaging Techniques

Aortic stenosis is the most common valvulopathy in the Western world. Its prevalence has increased significantly in recent years due to population aging; hence, up to 8% of westerners above the age of 84 now have severe aortic stenosis (Lindroos et al., 1993). This causes increased morbidity and mortality and therein lies the importance of adequate diagnosis and stratification of the degree of severity which allows planning the best therapeutic option in each case. Long understood as a passive age-related degenerative process, it is now considered a rather more complex entity involving mechanisms and factors similar to those of atherosclerosis (Stewart et al., 1997). In this review, we summarize the pathophysiological mechanisms underlying the onset and progression of the disease and analyze the current role of cardiac imaging techniques for diagnosis.

Multimodality Imaging for Planning and Follow-up of Transcatheter Aortic Valve Replacement

The complementary modalities of Doppler echocardiography and multidetector computed tomography are most frequently used for the planning and follow-up of transcatheter aortic valve replacement (TAVR). TAVR is now a well-established modality in the treatment of high-risk and inoperable patients with symptomatic severe aortic stenosis. Furthermore, recent studies have shown that TAVR is equivalent or superior to surgical aortic valve replacement in patients at intermediate surgical risk. We review the most commonly used imaging modalities and discuss their respective strengths and contributions to optimal patient selection, procedure planning, implementation, and follow-up in TAVR.

Patient selection for transcatheter aortic valve replacement: A combined clinical and multimodality imaging approach

Transcatheter aortic valve replacement (TAVR) has been validated as a new therapy for patients affected by severe symptomatic aortic stenosis who are not eligible for surgical intervention because of major contraindication or high operative risk. Patient selection for TAVR should be based not only on accurate assessment of aortic stenosis morphology, but also on several clinical and functional data. Multi-Imaging modalities should be preferred for assessing the anatomy and the dimensions of the aortic valve and annulus before TAVR. Ultrasounds represent the first line tool in evaluation of this patients giving detailed anatomic description of aortic valve complex and allowing estimating with enough reliability the hemodynamic entity of valvular stenosis. Angiography should be used to assess coronary involvement and plan a revascularization strategy before the implant. Multislice computed tomography play a central role as it can give anatomical details in order to choice the best fitting prosthesis, evaluate the morphology of the access path and detect other relevant comorbidities. Cardiovascular magnetic resonance and positron emission tomography are emergent modality helpful in aortic stenosis evaluation. The aim of this review is to give an overview on TAVR clinical and technical aspects essential for adequate selection.

Pulmonary Hypertension in Aortic Stenosis and Mitral Regurgitation: Rest and Exercise Echocardiography Significance

Valvular heart disease is a common cause of increased mean pulmonary artery pressure (PAP). Aortic stenosis and mitral regurgitation are frequently accompanied by pulmonary hypertension (PH), especially when they are severe and symptomatic. In asymptomatic patients, PH is rare, though the exact prevalence is unknown and mainly stems from the severity of the valvular heart disease and the presence of diastolic dysfunction. Exercise echocardiography has recently gained interest in depicting PH. In these asymptomatic patients, exercise PH is observed in about >40%. Either PH at rest (systolic PAP >50 mmHg) or during exercise (systolic PAP >60 mmHg) is a powerful determinant of outcome and is independently associated with reduced survival, regardless of the severity of the underlying valvular pathology.