Machine learning as a new frontier in mitral valve surgical strategy.

BACKGROUND: One of the surgical options available for ischemic mitral regurgitation (MR) is mitral valve repair but is limited by recurrent regurgitation as it is experienced by a significant percentage of patients and has a negative impact on patient outcomes. Efforts to model and identify predictors of recurrent MR rely on complicated echocardiographic and clinical measurements that are subjective and not routinely collected. AIMS: Kachroo et al. approached this problem in a unique way by using the STS database and machine learning (ML) to develop models that predict recurrent MR or death at 1 year. DISCUSSION: The STS database contains many routinely collected demographic and clinical parameters but requires a methodology, such as ML, that will accommodate collinearity and the unknown significance of many predictors. Kachroo et al. developed three good ML models with the area under curve 0.72-0.75. Data-driven selection of important predictors showed that three revascularization targets, peripheral vascular disease, and use of ß-blockers are most predictive of recurrent MR. CONCLUSION: We applaud the authors for pioneering a novel methodology and paving the way for a bright future in ML which includes integrating medical imaging, waveform, and genomic data to practice personalized medicine for our patients.

Randomized, Controlled Trial Comparing Mitral Valve Repair With Leaflet Resection Versus Leaflet Preservation on Functional Mitral Stenosis: The CAMRA CardioLink-2 Study.

BACKGROUND: Equipoise exists between the use of leaflet resection and preservation for surgical repair of mitral regurgitation caused by prolapse. We therefore performed a randomized, controlled trial comparing these 2 techniques, particularly in regard to functional mitral stenosis. METHODS: One hundred four patients with degenerative mitral regurgitation surgically amenable to either leaflet resection or preservation were randomized at 7 specialized cardiac surgical centers. Exclusion criteria included anterior leaflet or commissural prolapse, as well as a mixed cause for mitral valve disease. Using previous data, we determined that a sample size of 88 subjects would provide 90% power to detect a 5-mm Hg difference in mean mitral valve gradient at peak exercise, assuming an SD of 6.7 mm with a 2-sided test with α=5% and 10% patient attrition. The primary end point was the mean mitral gradient at peak exercise 12 months after repair. RESULTS: Patient age, proportion who were female, and Society of Thoracic Surgeons risk score were 63.9±10.4 years, 19%, and 1.4±2.8% for those who were assigned to leaflet resection (n=54), and 66.3±10.8 years, 16%, and 1.9±2.6% for those who underwent leaflet preservation (n=50). There were no perioperative deaths or conversions to replacement. At 12 months, moderate mitral regurgitation was observed in 3 subjects in the leaflet resection group and 2 in the leaflet preservation group. The mean transmitral gradient at 12 months during peak exercise was 9.1±5.2 mm Hg after leaflet resection and 8.3±3.3 mm Hg after leaflet preservation (P=0.43). The participants had similar resting peak (8.3±4.4 mm Hg versus 8.4±2.6 mm Hg; P=0.96) and mean resting (3.2±1.9 mm Hg versus 3.1±1.1 mm Hg; P=0.67) mitral gradients after leaflet resection and leaflet preservation, respectively. The 6-minute walking distance was 451±147 m for those in the leaflet resection versus 481±95 m for the leaflet preservation group (P=0.27). CONCLUSIONS: In this adequately powered randomized trial, repair of mitral prolapse with either leaflet resection or leaflet preservation was associated with similar transmitral gradients at peak exercise at 12 months postoperatively. These data do not support the hypothesis that a strategy of leaflet resection (versus preservation) is associated with a risk of functional mitral stenosis. Registration: URL: https://www.clinicaltrials.gov; Unique identifier NCT02552771.

Three-dimensional echocardiographic acquisition and validity of left ventricular volumes and ejection fraction.

Transthoracic (TTE) and transesophageal (TEE) three-dimensional echocardiography (3DE) is now used in daily clinical practice. Advancements in technology have improved image acquisition with higher frame rates and increased resolution. Different 3DE acquisition techniques can be used depending upon the structure of interest and if volumetric analysis is required. Measurements of left ventricular (LV) volumes are the most common use of 3DE clinically but are highly dependent upon image quality. Three-dimensional LV function analysis has been made easier with the development of automated software, which has been found to be highly reproducible. However, further research is needed to develop normal reference range values of LV function for both 3D TTE and TEE.

Vascular Complications and Procedures Following Transcatheter Aortic Valve Implantation.

OBJECTIVES: Vascular complications (VCs) remain a significant cause of morbidity in transcatheter aortic valve implantation (TAVI) patients and are associated with worse outcomes. This research analysed the incidence, impact, and predictors of VCs in transfemoral cases. METHODS: A retrospective chart review was performed of 388 consecutive TAVI patients between January 2007 and April 2015, which included 237 transfemoral cases. Major and minor VCs were characterised according to the Valve Academic Research Consortium (VARC) guidelines. Logistic regression was completed to identify predictors of VCs. RESULTS: While VCs occurred in 68 (28.7%) cases, only seven (3.38%) were classified as major complications. Twenty-six (10.9%) of these complications occurred intra-operatively, with four being major (1.6%) and 22 minor (9.3%). Post-operative VCs occurred in 42 cases (17.2%), with three (1.3%) being major. Procedures to correct VCs occurred in 10 (4.2%) cases, with the majority (90%) being surgical and the remainder being treated by endovascular techniques. Nine surgical procedures, predominantly embolectomy, were performed to correct post-operative complications. Female gender was a predictor of all major VCs (B = -2.1, p < .006). Further, a logistic regression analysis found that when the largest sheath was located on the left side, there were increased minor post-operative complications (B = -0.99, p = .007). Dissections and haematomas made up the majority of VCs. Thirty day mortality was six patients (n = 2.5%), and peri-operative VCs were significantly correlated with 30 day mortality (p = .001, R = 0.21). The 30 day readmission rate comprised nine patients (3.8%), with three (1.3%) due to VCs, including haematomas and groin infections. CONCLUSIONS: VCs contribute to operative morbidity in TAVI patients. This study demonstrated low major VC rates over an eight year period. Left sided location of largest sheath size and female gender were predictors of VC.

Aortic root changes before and after surgery for chronic aortic dilatation: A 3D echocardiographic study.

BACKGROUND: Quantitative 3D assessment of the aortic root may improve planning and success of aortic valve (AV)-sparing operations. AIMS: To use 3D transesophageal echocardiography (TEE) to assess the effect of chronic aortic dilatation on aortic root shape and aortic regurgitation (AR) severity and to examine the effects of AV-sparing operations. METHODS AND RESULTS: To determine the changes with chronic aortic dilatation, we studied 48 patients, 23 with aortic dilatation (Group 1 ≤ mild AR, n = 13; Group 2 ≥ moderate AR, n = 10) and 25 Controls. To determine the changes in AV-sparing operations, a subgroup of 15 patients were examined pre- and post surgery. 3D-TEE images were analyzed using multiplanar reconstruction (QLAB, Philips, Philips Medical Systems, Andover, MA, USA) to obtain aortic root areas, diameters, and lengths. We also calculated a novel parameter called total coaptation surface area (TCoapSA), which sums the contact surface area of all the AV cusps. Compared to Controls, Groups 1 and 2 had significantly larger aortic root areas, inter-commissural distances, and cusp heights. Compared to Group 1 and Controls, Group 2 had significantly smaller TCoapSA when adjusted for aortic annular area (P = 0.001) with shorter coaptation height (P < 0.001). In patients undergoing AV-sparing surgery, TCoapSA was significantly larger post surgery (P = 0.001) with greater coaptation height (P < 0.001) and smaller inter-commissural distances (P < 0.001). CONCLUSIONS: The aortic valve is a dynamic structure that remodels in response to aortic dilatation. Successful valve-sparing surgery corrects these changes. Quantitative modeling of the aortic valve and root could potentially improve the repair to the individual patients and modify outcomes.

Evaluation of the Clinical Utility of Transesophageal Echocardiography and Invasive Monitoring to Assess Right Ventricular Function During and After Pulmonary Endarterectomy.

OBJECTIVE: Patients undergoing pulmonary endarterectomy (PEA) have impaired right ventricular function. The authors sought to assess the clinical utility of commonly used perioperative echocardiographic and right heart catheter measurements in patients undergoing PEA. DESIGN: A single-center prospective observational study. SETTING: The study was conducted in a quaternary care cardiac surgical center in the United Kingdom. PARTICIPANTS: Patients undergoing PEA between April 2015 and January 2016. INTERVENTIONS: Thermodilution cardiac index and echocardiography variables were measured at 3 time points: before sternotomy (T1), after pericardial incision (T2), and after sternal closure (T3). Six-month follow-up echocardiography and 6-minute walk (6-MWT) test were performed. MEASUREMENTS AND MAIN RESULTS: Fifty patients were recruited and complete data sets were available for 41 patients. Tricuspid annular plane systolic excursion declined after pericardial incision and cardiopulmonary bypass (T1: 15 ± 4 mm, T2: 13 ± 4 mm, T3: 7 ± 2 mm; p < 0.0001), returning to baseline 6 months postoperatively. Cardiac index (T1: 2.5 ± 0.7 L/min/m2, T2: 2.6 ± 0.6 L/min/m2, T3: 2.3 ± 0.5 L/min/m2; p = 0.07) and right ventricular fractional area change (T1: 36 ± 11%, T2: 40 ± 12%, T3: 40 ± 9%; p = 0.12) were preserved perioperatively. 6-MWT improved from baseline (294 ± 111 m) to follow-up (357 ± 107 m) (p < 0.001). Pulmonary vascular resistance at T3 correlated moderately with follow-up 6-MWT (R = -0.60). CONCLUSIONS: In patients undergoing PEA, invasive measurements and echocardiography assessment of right ventricular function are not interchangeable. Tricuspid annular plane systolic excursion is not a reliable measure of right ventricular function perioperatively. Pulmonary vascular resistance shows moderate correlation with postoperative functional capacity.

Double trouble: A case of periprocedural detection of intracardiac thrombus and aortic root dissection during emergent transfemoral TAVR.

We report a case of emergency transcatheter aortic valve replacement (TAVR) in a 65-year-old patient presenting with decompensated severe aortic stenosis. Transesophageal echocardiography (TEE) was used effectively to obtain measurements of the aortic annulus and for intra-procedural guidance. At baseline, we detected a left atrial appendage thrombus and a localized aortic root dissection after balloon valvuloplasty. The case highlights the important role that TEE may play during TAVR procedures.

Right ventricular strain in pulmonary arterial hypertension: a 2D echocardiography and cardiac magnetic resonance study.

BACKGROUND: Right ventricular (RV) strain is a potentially useful prognostic marker in patients with pulmonary arterial hypertension (PAH). However, published reports regarding the accuracy of two-dimensional echocardiography (2DE)-derived RV strain against an independent reference in this patient population are limited. The aims of this study were: (1) to study the relationship between 2DE RV longitudinal strain and cardiovascular magnetic resonance (CMR)-derived RV ejection fraction (RVEF) in patients with PAH; (2) to compare 2DE-derived and CMR-derived RV longitudinal strain in these patients; and (3) to determine the reproducibility of these measurements. METHODS: Thirty patients with PAH underwent 2DE and CMR imaging within a 2-hour time period. 2DE RV longitudinal strain was measured from a focused RV apical four-chamber view using speckle tracking software. CMR RV longitudinal strain was measured from short-axis slices acquired using fast-strain-encoded sequence. Global peak systolic RV longitudinal strain was calculated for both 2DE and CMR. RESULTS: RV longitudinal strain using 2DE software correlated well with CMR-derived RVEF (R = 0.69, P = 0.0006). There was moderate agreement when comparing 2DE to CMR RV longitudinal strain (R = 0.74, P = 0.0002; bias -1%, limits of agreement -9 to 7%). Inter-observer variability and intra-observer variability for RV longitudinal strain were lower for 2DE than CMR. CONCLUSIONS: RV longitudinal strain by 2DE provides a good alternative for CMR-derived RVEF in patients with PAH. The moderate agreement in strain measurements between 2DE and CMR suggests that further software improvements are needed before these measurements can be used interchangeably in clinical practice.

Approach to Imaging of Patients Presenting With Acute Coronary Syndrome With No Culprit Lesion Identified at Angiography.

Chest pain is a common chief complaint among patients presenting to the emergency department. However, in the scenario where the clinical presentation is consistent with acute coronary syndrome and no culprit lesions are identified on angiography, clinicians and cardiac imagers should be informed of the differential diagnosis and appropriate imaging modalities used to investigate the potential causes. This review describes an imaging-based algorithm that highlights the diagnostic possibilities, their differentiating imaging features, and the important role of cardiovascular magnetic resonance imaging for narrowing the differential diagnosis.

Guidelines for the Evaluation of Prosthetic Valve Function With Cardiovascular Imaging: A Report From the American Society of Echocardiography Developed in Collaboration With the Society for Cardiovascular Magnetic Resonance and the Society of Cardiovascular Computed Tomography.

In patients with significant cardiac valvular disease, intervention with either valve repair or valve replacement may be inevitable. Although valve repair is frequently performed, especially for mitral and tricuspid regurgitation, valve replacement remains common, particularly in adults. Diagnostic methods are often needed to assess the function of the prosthesis. Echocardiography is the first-line method for noninvasive evaluation of prosthetic valve function. The transthoracic approach is complemented with two-dimensional and three-dimensional transesophageal echocardiography for further refinement of valve morphology and function when needed. More recently, advances in computed tomography and cardiac magnetic resonance have enhanced their roles in evaluating valvular heart disease. This document offers a review of the echocardiographic techniques used and provides recommendations and general guidelines for evaluation of prosthetic valve function on the basis of the scientific literature and consensus of a panel of experts. This guideline discusses the role of advanced imaging with transesophageal echocardiography, cardiac computed tomography, and cardiac magnetic resonance in evaluating prosthetic valve structure, function, and regurgitation. It replaces the 2009 American Society of Echocardiography guideline on prosthetic valves and complements the 2019 guideline on the evaluation of valvular regurgitation after percutaneous valve repair or replacement.

Reporting and representation of ethnic minorities in cardiovascular trials: a systematic review.

BACKGROUND: Ethnic minority groups in the United States are at increased risk of developing cardiovascular diseases, experiencing adverse outcomes, and receiving suboptimal treatment. Such discrepancies may be related to a difference in race-specific outcomes in the management of cardiovascular diseases. However, little is known about the reporting and representation of ethnic minorities in major cardiovascular trials. METHODS: A systematic review of major cardiovascular randomized controlled trials published in The Journal of the American Medical Association, The Lancet, and The New England Journal of Medicine between 1997 and 2010 was performed. We determined the reporting rate of the following ethnic minority groups in studies that enrolled American patients: whites, African Americans, Asians, and Hispanics. RESULTS: A total of 250 randomized controlled trials that enrolled 1,103,694 patients were included in the systematic review. Among them, 56% (n = 140) of the trials reported information on race. No significant temporal changes in racial reporting were observed during the study period (P = .21). The median enrollment rate in trials for whites, African Americans, Hispanics, and Asians was 86%, 7%, 6%, and 4%, respectively. When compared with the population prevalence of disease burden, we found that whites were overrepresented (88% vs 78%, P < .001), whereas African Americans were underrepresented (3% vs 11%, P < .001), in trials of coronary artery disease. CONCLUSIONS: Despite significant changes in the ethnic composition of the United States, we found that only about half of all major cardiovascular trials reported any racial information. Underrepresentation of ethnic minority groups in cardiovascular trials was observed.

Mixed aortic stenosis and regurgitation: a clinical conundrum.

Mixed aortic stenosis (AS) and aortic regurgitation (AR) is the most frequent concomitant valve disease worldwide and represents a heterogeneous population ranging from mild AS with severe AR to mild AR with severe AS. About 6.8% of patients with at least moderate AS will also have moderate or greater AR, and 17.9% of patients with at least moderate AR will suffer from moderate or greater AS. Interest in mixed AS/AR has increased, with studies demonstrating that patients with moderate mixed AS/AR have similar outcomes to those with isolated severe AS. The diagnosis and quantification of mixed AS/AR severity are predominantly echocardiography-based, but the combined lesions lead to significant limitations in the assessment. Aortic valve peak velocity is the best parameter to evaluate the combined haemodynamic impact of both lesions, with a peak velocity greater than 4.0 m/s suggesting severe mixed AS/AR. Moreover, symptoms, increased left ventricular wall thickness and filling pressures, and abnormal left ventricular global longitudinal strain likely identify high-risk patients who may benefit from closer follow-up. Although guidelines recommend interventions based on the predominant lesion, some patients could potentially benefit from earlier intervention. Once a patient is deemed to require intervention, for patients receiving transcatheter valves, the presence of mixed AS/AR could confer benefit to those at high risk of paravalvular leak. Overall, the current approach of managing patients based on the dominant lesion might be too reductionist and a more holistic approach including biomarkers and multimodality imaging cardiac remodelling and inflammation data might be more appropriate.

Multimodality Quantitative Assessment of Aortic Regurgitation: A Systematic Review.

We performed a systematic review on the agreement and reproducibility of 3 advanced imaging methods, 3-dimensional echocardiography (3DE), cardiac computed tomography (CCT), and cardiac magnetic resonance (CMR), for quantifying aortic regurgitation (AR) severity. Medline, Embase, and Cochrane databases were systematically searched using the PICO model from inception to February 4, 2022, for publications that quantified AR severity with 3DE, CCT, or CMR. Measurement agreement and intraobserver and interobserver reproducibility results were extracted from each study. Study quality was assessed using the QUADAS-2 tool. Forty-two publications with 2176 patients with AR were identified. For 3DE, vena contracta (VC) width, VC area, and effective regurgitant orifice area had higher correlations with AR volume than the 2-dimensional echocardiography (2DE)-derived VC width. CCT-derived regurgitant volume had moderate-to-good correlations with 2DE. CMR regurgitant volume measurements had lower intraobserver and interobserver variabilities because of improved endocardial definition, fewer geometric assumptions, and less angle dependence for flow measurements when compared with 2DE. 3DE color flow convergence methods used to quantify AR severity were superior to 2DE methods and could be used in patients with adequate echocardiographic windows. CCT methods also demonstrated improvements over 2DE methods. Although this method is limited due to the radiation exposure, it could play a role in patients with poor echocardiographic windows unable to tolerate CMR. CMR demonstrated the smallest intraobserver and interobserver variability in evaluating AR severity and is a reasonable option for those where the echocardiographic results are mixed and for clinical trials.

The "Lightbulb" Sign: A Novel Echocardiographic Finding Using Ultrasound Enhancing Agent in Fulminant COVID-19-Related Myocarditis.

We report a case of fulminant COVID-19-related myocarditis requiring venoarterial extracorporeal membrane oxygenation where the use of an ultrasound-enhancing agent demonstrated a previously undescribed echocardiographic finding, the "lightbulb" sign. This sign potentially represents a new area for the use of an ultrasound enhancing agent in the echocardiographic diagnosis of myocarditis.

Mitral repair with leaflet preservation versus leaflet resection and ventricular reverse remodeling from a randomized trial.

OBJECTIVES: In the Canadian Mitral Research Alliance (CAMRA) Trial CardioLink-2 leaflet resection versus preservation techniques for posterior leaflet prolapse was investigated and no difference was shown in their effect on mean mitral gradient at peak exercise at 12 months postoperatively. The purpose of this subanalysis was to evaluate the effect of the 2 strategies on left ventricular (LV) reverse remodeling after repair. METHODS: A total of 104 patients were randomized to either a leaflet resection or leaflet preservation strategy. Echocardiograms, performed at baseline (preoperative), predischarge, and 12 months postoperatively, were analyzed in a blinded fashion at a core laboratory. RESULTS: All patients underwent successful mitral repair. At discharge, 3 patients showed moderate mitral regurgitation, whereas the remainder showed mild or less regurgitation. Compared with the baseline echocardiogram, the indexed end diastolic volume was reduced at the discharge echocardiogram (P < .0001) and was further reduced at the 12-month echocardiogram (P = .01). In contrast, the indexed end systolic volume did not significantly change from baseline assessed at the predischarge echocardiogram (P = .32) but improved at 12 months postoperatively (P < .0001), resulting in a corresponding improvement in ejection fraction at 12 months (P < .0001). The type of mitral repair strategy had no significant effect on LV reverse remodeling trends. CONCLUSIONS: The mitral repair strategies used did not influence postoperative LV reverse remodeling, which occurred in stages. Although LV end diastolic dimensions recovered before discharge, improvements in LV end systolic dimension were evident 12 months after repair.

Interpretable machine learning for automated left ventricular scar quantification in hypertrophic cardiomyopathy patients.

Scar quantification on cardiovascular magnetic resonance (CMR) late gadolinium enhancement (LGE) images is important in risk stratifying patients with hypertrophic cardiomyopathy (HCM) due to the importance of scar burden in predicting clinical outcomes. We aimed to develop a machine learning (ML) model that contours left ventricular (LV) endo- and epicardial borders and quantifies CMR LGE images from HCM patients.We retrospectively studied 2557 unprocessed images from 307 HCM patients followed at the University Health Network (Canada) and Tufts Medical Center (USA). LGE images were manually segmented by two experts using two different software packages. Using 6SD LGE intensity cutoff as the gold standard, a 2-dimensional convolutional neural network (CNN) was trained on 80% and tested on the remaining 20% of the data. Model performance was evaluated using the Dice Similarity Coefficient (DSC), Bland-Altman, and Pearson's correlation. The 6SD model DSC scores were good to excellent at 0.91 ± 0.04, 0.83 ± 0.03, and 0.64 ± 0.09 for the LV endocardium, epicardium, and scar segmentation, respectively. The bias and limits of agreement for the percentage of LGE to LV mass were low (-0.53 ± 2.71%), and correlation high (r = 0.92). This fully automated interpretable ML algorithm allows rapid and accurate scar quantification from CMR LGE images. This program does not require manual image pre-processing, and was trained with multiple experts and software, increasing its generalizability.

Deep learning assisted measurement of echocardiographic left heart parameters: improvement in interobserver variability and workflow efficiency.

Machine learning techniques designed to recognize views and perform measurements are increasingly used to address the need for automation of the interpretation of echocardiographic images. The current study was designed to determine whether a recently developed and validated deep learning (DL) algorithm for automated measurements of echocardiographic parameters of left heart chamber size and function can improve the reproducibility and shorten the analysis time, compared to the conventional methodology. The DL algorithm trained to identify standard views and provide automated measurements of 20 standard parameters, was applied to images obtained in 12 randomly selected echocardiographic studies. The resultant measurements were reviewed and revised as necessary by 10 independent expert readers. The same readers also performed conventional manual measurements, which were averaged and used as the reference standard for the DL-assisted approach with and without the manual revisions. Inter-reader variability was quantified using coefficients of variation, which together with analysis times, were compared between the conventional reads and the DL-assisted approach. The fully automated DL measurements showed good agreement with the reference technique: Bland-Altman biases 0-14% of the measured values. Manual revisions resulted in only minor improvement in accuracy: biases 0-11%. This DL-assisted approach resulted in a 43% decrease in analysis time and less inter-reader variability than the conventional methodology: 2-3 times smaller coefficients of variation. In conclusion, DL-assisted approach to analysis of echocardiographic images can provide accurate left heart measurements with the added benefits of improved reproducibility and time savings, compared to conventional methodology.

Age-, Sex-, and Race-Based Normal Values for Left Ventricular Circumferential Strain from the World Alliance Societies of Echocardiography Study.

BACKGROUND: Left ventricular (LV) circumferential strain has received less attention than longitudinal deformation, which has recently become part of routine clinical practice. Among other reasons, this is because of the lack of established normal values. Accordingly, the aim of this study was to establish normative values for LV circumferential strain and determine sex-, age-, and race-related differences in a large cohort of healthy adults. METHODS: Complete two-dimensional transthoracic echocardiograms were obtained in 1,572 healthy subjects (51% men), enrolled in the World Alliance Societies of Echocardiography Normal Values Study. Subjects were divided into three age groups (<35, 35-55, and >55 years) and stratified by sex and by race. Vendor-independent semiautomated speckle-tracking software was used to determine LV regional circumferential strain and global circumferential strain (GCS) values. Limits of normal for each measurement were defined as 95% of the corresponding sex and age group falling between the 2.5th and 97.5th percentiles. Intergroup differences were analyzed using unpaired t tests. RESULTS: Circumferential strain showed a gradient, with lower magnitude at the mitral valve level, increasing progressively toward the apex. Compared with men, women had statistically higher magnitudes of regional and global strain. Older age was associated with a stepwise increase in GCS despite an unaffected ejection fraction, a decrease in LV volume, and relatively stable global longitudinal strain in men, with a small gradual decrease in women. Asian subjects demonstrated significantly higher GCS magnitudes than whites of both sexes and blacks among women only. In contrast, no significant differences in GCS were found between white and black subjects of either sex. Importantly, despite statistical significance of these differences across sex, age, and race, circumferential strain values were similar in all groups, with variations of the order of magnitude of 1% to 2%. Notably, no differences in GCS were found among brands of imaging equipment. CONCLUSION: This study established normal values of LV regional circumferential strain and GCS and identified sex-, age-, and race-related differences when present.

Normal Values of Left Ventricular Mass by Two-Dimensional and Three-Dimensional Echocardiography: Results from the World Alliance Societies of Echocardiography Normal Values Study.

BACKGROUND: Although increased left ventricular (LV) mass is associated with adverse outcomes, measured values vary widely depending on the specific technique used. Moreover, the impact of sex, age, and race on LV mass remains controversial, further limiting the clinical use of this parameter. Accordingly, the authors studied LV mass using a variety of two-dimensional and three-dimensional echocardiographic techniques in a large population of normal subjects encompassing a wide range of ages. METHODS: Transthoracic echocardiograms obtained from 1,854 healthy adult subjects (52% men) enrolled in the World Alliance Societies of Echocardiography (WASE) Normal Values Study, were divided into three age groups (young, 18-35 years; middle aged, 36-55 years; and old, >55 years). LV mass was obtained using five conventional techniques, including linear and two-dimensional methods, as well as direct three-dimensional measurement. All LV mass values were indexed to body surface area, and differences according to sex, age, and race were analyzed for each technique. RESULTS: LV mass values differed significantly among the five techniques. Three-dimensional measurements were considerably smaller than those obtained using the other techniques and were closer to magnetic resonance imaging normal values reported in the literature. For all techniques, LV mass in men was significantly larger than in women, with and without body surface area indexing. These technique- and sex-related differences were larger than measurement variability. In women, age differences in LV mass were more pronounced and depicted significantly larger values in older age groups for all techniques, except three-dimensional echocardiography, which showed essentially no differences. LV mass was overall larger in black subjects than in white or Asian subjects. CONCLUSIONS: Significant differences in LV mass values exist across echocardiographic techniques, which are therefore not interchangeable. Sex-, race-, and age-related differences underscore the need for separate population specific normal values.

Normative values of the aortic valve area and Doppler measurements using two-dimensional transthoracic echocardiography: results from the Multicentre World Alliance of Societies of Echocardiography Study.

AIMS: Aortic valve area (AVA) used for echocardiographic assessment of aortic stenosis (AS) has been traditionally interpreted independently of sex, age and race. As differences in normal values might impact clinical decision-making, we aimed to establish sex-, age- and race-specific normative values for AVA and Doppler parameters using data from the World Alliance Societies of Echocardiography (WASE) Study. METHODS AND RESULTS: Two-dimensional transthoracic echocardiographic studies were obtained from 1903 healthy adult subjects (48% women). Measurements of the left ventricular outflow tract (LVOT) diameter and Doppler parameters, including AV and LVOT velocity time integrals (VTIs), AV mean pressure gradient, peak velocity, were obtained according to ASE/EACVI guidelines. AVA was calculated using the continuity equation. Compared with men, women had smaller LVOT diameters and AVA values, and higher AV peak velocities and mean gradients (all P < 0.05). LVOT and AV VTI were significantly higher in women (P < 0.05), and both parameters increased with age in both sexes. AVA differences persisted after indexing to body surface area. According to the current diagnostic criteria, 13.5% of women would have been considered to have mild AS and 1.4% moderate AS. LVOT diameter and AVA were lower in older subjects, both men and women, and were lower in Asians, compared with whites and blacks. CONCLUSION: WASE data provide clinically relevant information about significant differences in normal AVA and Doppler parameters according to sex, age, and race. The implementation of this information into clinical practice should involve development of specific normative values for each ethnic group using standardized methodology.