Pulmonary hypertension in remote and disadvantaged population: overcoming unique challenges for improved outcomes.

Pulmonary hypertension (PH) is a common and debilitating medical condition with high mortality. PH research has traditionally focused on pulmonary arterial hypertension and its management in expert PH centres. Other forms of PH such as PH associated with cardiac or respiratory disease are more common, less well-understood and associated with higher mortality. Epidemiology of PH in disadvantaged, remote and rural regions, remains largely undocumented. In this review, we discuss the unique challenges in identifying PH in rural and disadvantaged populations using the Top End region of the Northern Territory of Australia as an example. We propose a simple diagnostic approach, ideally suited to regions where resource allocation is scarce, using clinical skills, echocardiography, and an escalation algorithm. The brief history, epidemiology and current literature on PH are summarised to inform the busy clinicians. We highlight two case examples from the Top End to illustrate the challenges and potential solutions.

Impact of inter-vendor variability on evaluation of left ventricular mechanical dispersion.

PURPOSE: Left ventricular mechanical dispersion (LVMD) is a novel speckle tracking parameter for prognostic assessment of arrhythmic risk prediction. There is growing evidence to support its use in a variety of cardiomyopathic processes. There is paucity of data addressing any presence of inter-vendor discrepancies for LVMD. The aim of this study was to assess inter-vendor variability of LVMD in vendor specific software (VSS) and vendor independent software (VIS) in subjects with preserved and reduced left ventricular function. METHODS: Fifty-nine subjects (14 normal subjects and 45 subjects with cardiac disease) were recruited and 2D speckle tracking echocardiographic images were acquired on two different ultrasound machines (GE and Philips). LVMD was measured by two different VSS (EchoPac GE and QLAB Philips) and one VIS (TomTec Arena). RESULTS: There was significant bias and wide limits of agreement (LOA) in the overall cohort observed between two different VSS (17.6 ms; LOA: -29.6 to 64.8; r: .47). There was acceptable bias and narrower LOA with good agreement for LVMD between images obtained on different vendors when performed on VIS (-3.1 ms; LOA: -27.6 to 21.4; r: .75). QLAB LVMD was consistently higher than GE LVMD and TomTec LVMD in both preserved and reduced left ventricular function. LVMD measurements have high intra-vendor reproducibility with excellent inter and intra-observer agreement. CONCLUSIONS: There was acceptable bias and narrower LOA for LVMD assessment on a VIS. Inter-vendor variability exists for LVMD assessment between VSS. Serial measurements of LVMD should be performed using a single vendor for consistent and reliable results.

Left atrial reservoir strain provides incremental value to left atrial volume index for evaluation of left ventricular filling pressure.

BACKGROUND: Left atrial analysis is employed in diastolic assessment with left atrial volume index (LAVI) incorporated in the 2016 ASE/EACVI diastology guideline algorithm. LAVI has sub-optimal correlation with invasive left ventricular filling pressure (LVFP) and incorporation of left atrial reservoir strain (LASr) may improve diastolic assessment. METHODS: A cross-sectional prospective study of 139 patients was undertaken with all patients undergoing transthoracic echocardiography immediately prior to cardiac catheterization with invasive evaluation of LVFP. LASr by speckle tracking echocardiography and conventional echocardiographic parameters were assessed in relation to invasive LVFP. Modification of the 2016 guideline algorithm was performed with incorporation of LASr in place of LAVI (LASr ≤23% indicating elevated LVFP). Accuracy of the modified and conventional algorithm were assessed for predicting invasive LVFP. RESULTS: The mean age was 63±12 years with 27% female. LASr demonstrated superior correlation and receiver operator characteristic for predicting LVFP than LAVI (LASr: r -.46 (p < 0.01), AUC: .82 vs LAVI: r .19 (p 0.02), AUC: .66). LASr of ≤23% was the optimal cut-off for discriminating elevated LVFP (sensitivity 80%, specificity 77%). Modification of the 2016 algorithm with incorporation of LASr in place of LAVI reclassified 12% of the patient cohort and improved concordance of echocardiographic and invasive LVFP assessment (modified algorithm κ .47 vs 2016 algorithm κ: .33). No patients were incorrectly reclassified by modified algorithm assessment. CONCLUSIONS: LASr better predicts invasive LVFP than LAVI. Modification of the 2016 guideline algorithm with incorporation of LASr in place of LAVI improves accuracy of echocardiographic assessment of LVFP.

Myocardial work and left ventricular contractile reserve during stress echocardiography: An angiographic validation.

OBJECTIVE: This study sought to determine the contractile reserve (CR) response to exercise stress echocardiography (ESE) quantified by the novel parameter, non-invasive myocardial work (MW), in subjects with angiographically proven coronary artery disease (CAD). METHODS: CR was measured by the relative change in ejection fraction (EF), global longitudinal strain (GLS) and MW indices from rest to peak exercise in 304 patients referred for clinically indicated ESE. Positive ESE patients proceeded to coronary angiography and further risk stratified based on either percutaneous or surgical intervention. RESULTS: CRGLS and global work index (CRGWI ) significantly decreased with exercise induced ischemia and angiographically proven significant CAD (CRGLS -1.6±3.5%; CRGWI -8.6±511 mm Hg% decrement, p < 0.001) compared to non-ischemic patients (CRGLS 1.4±2.2%; CRGWI 398±404 mm Hg% improvement). Global constructive work (CRGCW ) was significantly higher (p < 0.0001) in non-ischemic (818±457 mm Hg%) and blunted in ischemic patients (208±550 mm Hg%). CRGCW (AUC .81; 95%CI:.75-.86) demonstrated the most association for inducible ischemia followed by CRGLS (AUC .75; 95%CI:.69-.80), CRGWI (AUC .73, 95%CI:.67-.79) and CREF (AUC .71; 95%CI:.65-.77, p < 0.001). Subgroup analysis showed patients requiring surgical revascularization demonstrated a significantly lower CRGWE (-11.5±7.6%, p < 0.05) as a result of reduced CRGCW (281±573 mm Hg%, p < 0.05) and increased global wasted work (CRGWW , 289±151 mm Hg%, p = 0.09). CONCLUSION: Multivessel disease requiring surgical revascularization have the greatest reduction in CR. MW may potentially improve detection of ischemia and further risk stratification during ESE to maximize the benefits of revascularization.

Uncovering the treatable burden of severe aortic stenosis in Australia: current and future projections within an ageing population.

BACKGROUND: We aimed to address the paucity of information describing the treatable burden of disease associated with severe aortic stenosis (AS) within Australia's ageing population. METHODS: A contemporary model of the population prevalence of symptomatic, severe AS and treatment pathways in Europe and North America was applied to the 2019 Australian population aged ≥ 55 years (7 million people) on an age-specific basis. Applying Australian-specific data, these estimates were used to further calculate the total number of associated deaths and incident cases of severe AS per annum. RESULTS: Based on an overall point prevalence of 1.48 % among those aged ≥ 55 years, we estimate that a minimum of 97,000 Australians are living with severe AS. With a 2-fold increased risk of mortality without undergoing aortic valve replacement (AVR), more than half of these individuals (∼56,000) will die within 5-years. From a clinical management perspective, among those with concurrent symptoms (68.3 %, 66,500 [95 % CI 59,000-74,000] cases) more than half (58.4 %, 38,800 [95 % CI 35,700 - 42,000] cases) would be potentially considered for surgical AVR (SAVR) - comprising 2,400, 5,400 and 31,000 cases assessed as high-, medium- or low peri-operative mortality risk, respectively. A further 17,000/27,700 (41.6 % [95 % CI 11,600 - 22,600]) of such individuals would be potentially considered to a transthoracic AVR (TAVR). During the subsequent 5-year period (2020-2024), each year, we estimate an additional 9,300 Australians aged ≥ 60 years will subsequently develop severe AS (6,300 of whom will experience concurrent symptoms). Of these symptomatic cases, an estimated 3,700 and 1,600 cases/annum, will be potentially suitable for SAVR and TAVR, respectively. CONCLUSIONS: These data suggest there is likely to be a substantive burden of individuals living with severe AS in Australia. Many of these cases may not have been diagnosed and/or received appropriate treatment (based on the evidence-based application of SAVR and TAVR) to reduce their high-risk of subsequent mortality.

Top End Pulmonary Hypertension Study: Understanding Epidemiology, Therapeutic Gaps and Prognosis in Remote Australian Setting.

INTRODUCTION: The Top End of Australia has a high proportion of Indigenous people with a high burden of chronic cardiac and pulmonary diseases likely to contribute to pulmonary hypertension (PH). The epidemiology of PH has not been previously studied in this region. METHODS: Patients with PH were identified from the Northern Territory echocardiography database from January 2010 to December 2015 and followed to the end of 2019 or death. Pulmonary hypertension was defined as a tricuspid regurgitation velocity ≥2.75 m/s measured by Doppler echocardiography. The aetiology of PH, as categorised by published guidelines, was determined by reviewing electronic health records. RESULTS: 1,764 patients were identified comprising 49% males and 45% Indigenous people. The prevalence of PH was 955 per 100,000 population (with corresponding prevalence of 1,587 for Indigenous people). Hypertension, atrial fibrillation, diabetes and respiratory disease were present in 85%, 45%, 41% and 39%, respectively. Left heart disease was the leading cause for PH (58%), the majority suffering from valvular disease (predominantly rheumatic). Pulmonary arterial hypertension (PAH), respiratory disease related PH, chronic thromboembolic PH (CTEPH) and unclear multifactorial PH represented 4%, 16%, 2% and 3%, respectively. Underlying causes were not identifiable in 17% of the patients. Only 31% of potentially eligible patients were on PAH-specific therapy. At census, there was 40% mortality, with major predictors being age, estimated pulmonary artery systolic pressure (ePASP) and Indigenous ethnicity. CONCLUSION: Pulmonary hypertension is prevalent in Northern Australia, with a high frequency of modifiable risk factors and other treatable conditions. Whether earlier diagnosis, interpretation and intervention improve outcomes merits further assessment.

Operator and Institutional Requirements for Transcatheter Mitral Valve Therapies in Australia: a CSANZ and ANZSCTS Position Statement.

This expert Position Statement is a description of the requirements for Accreditation for transcatheter mitral valve therapy (TMVT) in Australia. The requirements include the need for a multidisciplinary Heart Team review of individual cases, mandatory reporting of outcome data to a national TMVT Registry, and accreditation of individuals and institutions by the Conjoint Accreditation Committee, the assigned accreditation authority.

The prognostic value of estimating stroke volume before and after exercise during treadmill stress echocardiography.

BACKGROUND: Stress echocardiography (SE) is an established technique for assessment of coronary artery disease (CAD) which is difficult to perform and interpret. Left ventricular stroke volume (SV) is readily estimated with Doppler echocardiography. It can be affected by myocardial ischemia, with possible adjunctive value during SE. METHODS: Patients underwent Bruce protocol SE with SV estimated before and after maximal treadmill exertion post routine regional wall analysis. Incremental change in SV (ΔSV) with exercise was measured. RESULTS: A derivation cohort (n = 273) was established to test the hypothesis. An optimal cutoff for detection on inducible ischemia was ΔSV ≤ +10 mL. The validation cohort of consecutive patients (n = 1093, 376 [34%] female; age 59 ± 12 years) were followed clinically after SE for 20 460 patient-months. There were 1000 patients with nonischemic SE, and 93 patients with studies suggestive of myocardial ischemia. Secondary analysis yielded 831 patients with a normal exercise response (ΔSV > +10 mL) and 192 with an abnormal ΔSV ≤ +10 mL. Time to first combined adverse cardiac event (composite of angina, acute coronary syndrome, cardiac revascularization, worsening New York Heart Association (NYHA) class, a reduction in EF, and cardiovascular death) was analyzed and adjusted using Cox proportional hazards regression. The hazard ratio for an adverse event with an abnormal ΔSV response (≤10 mL) was 10.3 (95% confidence intervals 5.6-19.1, P < .0001). CONCLUSIONS: Stroke volume assessment during SE is feasible and readily performed. It is simple, practical, and has incremental diagnostic and prognostic value when added to exercise regional wall-motion analysis.

Female False Positive Exercise Stress ECG Testing - Fact Versus Fiction.

BACKGROUND: Exercise stress testing is a well validated cardiovascular investigation. Accuracy for treadmill stress electrocardiograph (ECG) testing has been documented at 60%. False positive stress ECGs (exercise ECG changes with non-obstructive disease on anatomical testing) are common, especially in women, limiting the effectiveness of the test. This study investigates the incidence and predictors of false positive stress ECG findings, referenced against stress echocardiography (SE) as a standard. METHODS: Stress echocardiography was performed using the Bruce treadmill protocol. False positive stress ECG tests were defined as greater than 1mm of ST depression on ECG during exertion, without pain, with a normal SE. Potential causes for false positive tests were recorded before the test. RESULTS: Three thousand (3,000) consecutive negative stress echocardiograms (1,036 females, 34.5%) were analysed (age 59+/-14 years. False positive (F+) stress ECGs were documented in 565/3,000 tests (18.8%). F+ stress ECGs were equally prevalent in females (194/1,036, 18.7%) and males (371/1,964, 18.9%, p=0.85 for the difference). Potential causes (hypertension, left ventricular hypertrophy, known coronary disease, arrhythmia, diabetes mellitus, valvular heart disease) were recorded in 36/194 (18.6%) of the female F+ ECG tests and 249/371 (68.2%) of the male F+ ECG tests (p<0.0001 for the difference). CONCLUSIONS: These data suggest that F+ stress ECG tests are frequent and equally common in women and men. However, most F+ stress ECGs in men can be predicted before the test, while most in women cannot. Being female may be a risk factor in itself. These data reinforce the value of stress imaging, particularly in women.

Estimation of the Blood Pressure Response With Exercise Stress Testing.

BACKGROUND: The blood pressure response to exercise has been described as a significant increase in systolic BP (sBP) with a smaller change in diastolic BP (dBP). This has been documented in small numbers, in healthy young men or in ethnic populations. This study examines these changes in low to intermediate risk of myocardial ischaemia in men and women over a wide age range. METHODS: Consecutive patients having stress echocardiography were analysed. Ischaemic tests were excluded. Manual BP was estimated before and during standard Bruce protocol treadmill testing. Patient age, sex, body mass index (BMI), and resting and peak exercise BP were recorded. RESULTS: 3,200 patients (mean age 58±12years) were included with 1,123 (35%) females, and 2,077 males, age range 18 to 93 years. Systolic BP increased from 125±17mmHg to 176±23mmHg. The change in sBP (ΔsBP) was 51mmHg (95% CI 51,52). The ΔdBP was 1mmHg (95% CI 1, 1), from 77 to 78mmHg, p<0.001). The upper limit of normal peak exercise sBP (determined by the 90th percentile) was 210mmHg in males and 200mmHg in females. The upper limit of normal ΔsBP was 80mmHg in males and 70mmHg in females. The lower limit of normal ΔsBP was 30mmHg in males and 20mmHg in females. CONCLUSIONS: In this large cohort, sBP increased significantly with exercise. Males had on average higher values than females. Similar changes were seen with the ΔsBP. The upper limit of normal for peak exercise sBP and ΔsBP are reported by age and gender.

The National Echocardiography Database Australia (NEDA): Rationale and methodology.

The National Echocardiography Database Australia (NEDA) is a new echocardiography database collecting digital measurements on both a retrospective and prospective basis. To date, echocardiographic data from 435,133 individuals (aged 61.6 ±â€¯17.9 years) with linkage to 59,725 all-cause deaths during a median of 40 months follow-up have been collected. These data will inform a number of initial analyses focusing on pulmonary hypertension, aortic stenosis and the role of artificial intelligence to facilitate accurate diagnoses of cardiac abnormalities.

Improving the echocardiographic assessment of pulmonary pressure using the tricuspid regurgitant signal-The "chin" vs the "beard".

AIM: Transthoracic echocardiography (TTE) is a fundamental investigation for the noninvasive assessment of pulmonary hemodynamics and right heart function. The aim of this study was to assess the correlation and agreement of Doppler calculation of right ventricular systolic pressure (RVSP) and pulmonary vascular resistance (PVR) using "chin" and "beard" measurements of tricuspid regurgitant velocity (TRVmax ), with invasive pulmonary artery systolic pressure (PASP) and PVR. METHODS: One hundred patients undergoing right heart catheterisation (RHC) and near simultaneous transthoracic echocardiography were studied. TRVmax was recorded for "chin" measurement (distinct peak TRVmax signal) and where available (63 patients), "beard" measurement (higher indistinct peak TRVmax signal). RESULTS: Measurable TRV signal was obtained in 96 patients. Mean RVSPchin 54.7 ± 22.7 mm Hg and RVSPbeard 68.6 = 23 ± 26.3 mm Hg (P < .001). There was strong correlation between both RVSPchin and RVSPbeard with invasive PASP (Pearson's r = .9, R2  = 0.82, P < .001 - r = .88, R = .78, P < .001, respectively.). Bland-Altman analysis for RVSPchin and RVSPbeard showed a mean bias of -0.5 mm Hg (95% limits of agreement -21.4 to 20.5 mm Hg) and -10.7 (95% LOA -35.5 to 14.2 mm Hg), respectively. Receiver operator characteristics of TRVmax "chin" and "beard" for diagnosis of pulmonary hypertension was assessed with optimal cut-offs being 2.8 m/s (sensitivity 93%, specificity 87%) and 3.2 m/s (sensitivity 91%, specificity 82%), respectively. There was similar correlation between PVRchin and PVRbeard (r = .87, R2  = 0.75, P < .001 and r = .86, R2  = 0.74, P < .001, respectively). At higher PVR, there was overestimation of calculated PVR using PVRbeard . CONCLUSION: The accuracy of noninvasive measurement of right heart pressures is increased using the "chin" in estimation of both RVSP and PVR.

Left Heart Disease and Pulmonary Hypertension: Are We Seeing the Full Picture?

Pulmonary hypertension (PH) is common, under diagnosed and associated with a high mortality. There are significant delays in the diagnosis of pulmonary hypertension leading to increased morbidity and delays in the initiation of treatment. Once PH is diagnosed, establishing the degree of pulmonary vascular resistance (PVR) enables clinicians to broadly divide the underlying pathology into pre-capillary or post-capillary causes, a crucial step in tailoring management. Pulmonary hypertension is most commonly due to left heart disease (PH-LHD) and echocardiography (echo) is the most widely accessible investigation in its diagnosis. Regardless of the underlying pathophysiology of LHD, the sequelae lead to pressure overload on the left heart and a reactive increase in pulmonary pressures. In this review article, we will discuss the prevalence of PH, examine the pathophysiology of PH-LHD, establish how echo can be used to identify patients with PH-LHD and discuss surrogate echo markers of PVR.

The New Dimension in Aortic Measurements - Use of the Inner Edge Measurement for the Thoracic Aorta in Australian Patients.

BACKGROUND: Historically, aortic measurements were established using M-mode echocardiography, measuring from the leading edge to leading edge. Improvements in echocardiographic imaging now permit accurate assessment using the blood-tissue interface. Normal values have not been established using this technique. METHODS: A prospective analysis of consecutive patients without pathology was conducted. Measurements of aortic dimensions were made using the blood-tissue interface and the leading edge methods at end-diastole, and at end-systole using the blood-tissue interface. Data collected included BSA, and aortic measurements (LVOT, root, ST junction, mid ascending aorta, aortic arch). RESULTS: The echocardiograms of 512 patients were evaluated. The mean age was 56 years, with 304 males (59%) and 208 females (41%). The average measurements (blood tissue interface) were: aortic root 31.2mm, sinotubular junction 25.9mm, mid ascending aorta 30.6 and aortic arch 23.4. On average, the leading edge method measurements were 1.5mm larger (p<0.0001), consistent with the added thickness of the anterior aortic wall. Ratios to BSA were also estimated. Tables have been created suggesting normal and abnormal values. CONCLUSIONS: Improvements in echocardiographic imaging permit the blood-tissue interface to be readily visualised. Reference ranges for the estimation of aortic sizes using this method are provided. More accurate and anatomical estimation of the aortic dimensions can now be achieved.

Pericardiocentesis ­ How to do it.

Pericardiocentesis is an important diagnostic and therapeutic technique, with the potential for significant morbidity and mortality if performed incorrectly. This article attempts to cover the anatomy, preparation, and techniques necessary to successfully perform pericardiocentesis.

The return of the normal heart: resolution of cardiac amyloidosis after chemotherapy and bone marrow transplantation.

BACKGROUND: AL amyloidosis and multiple myeloma result in extracellular deposition of insoluble fibrillar protein in tissues and organs. Untreated median survival has been documented at 12 months. Cardiac infiltration decreases survival to five months. Chemotherapy and bone marrow transplantation (BMT) have been shown to improve survival when haematological remission is documented. This study aimed to assess if remission could result in cardiac structural improvement. METHODS: 269 patients were treated with BMT for amyloidosis from 1997 to 2010. Cardiac amyloidosis was identified in 30 patients by echocardiographic criteria. Echocardiography was performed before and after BMT. RESULTS: Thirteen of 30 patients with cardiac amyloidosis died during follow-up. No change in cardiac structure was seen in 11 patients. Average survival was 49 months from BMT for non-responders. Fifteen patients had cardiac normalisation (responders). The average time to normalisation was 25 months. Only two responders died. Average survival for responders was 71 months (p < 0.0001 compared with non-responders). Normalisation of cardiac structure was highly predictive of survival (Fisher's exact test p = 0.0025, relative risk 0.18). CONCLUSIONS: Cardiac amyloidosis patients with haematological remission after chemotherapy and BMT may subsequently normalise cardiac structure and function. Normalisation is highly predictive of survival.

Perforated mitral valve annular phlegmon with ventriculo-atrial fistula.

Herein we describe a case of perforated mitral valve annular abscess/phlegmon that presented as a new pan-systolic murmur in the setting of hallux osteomyelitis requiring amputation. We discuss the investigations, imaging and complex management challenges arising from this rare condition and the importance of considering a diagnosis of infective endocarditis in patients with a new cardiac murmur.

Atrial functional mitral regurgitation: prevalence, characteristics and outcomes from the National Echo Database of Australia.

AIMS: Atrial functional mitral regurgitation (AFMR) is characterised by left atrial and consequent mitral annular dilatation causing mitral regurgitation. AFMR is likely to become more common with population ageing, alongside increases in atrial fibrillation and heart failure with preserved ejection fraction; conditions causing atrial dilatation. Here, we aim to define the prevalence and characterise the patient and survival characteristics of AFMR in the National Echocardiographic Database of Australia (NEDA). METHODS AND RESULTS: 14 004 adults with moderate or severe FMR were identified from NEDA. AFMR or ventricular FMR (VFMR) was classified by LA size, LV size and LVEF. AFMR was found in 40% (n=5562) and VFMR in 60% (n=8442). Compared with VFMR, the AFMR subgroup were significantly older (mean age 78±11 years), with a higher proportion of females and of AF. Participants were followed up for a median of 65 months (IQR 36-116 months). After adjustment for age, sex, AF, and pulmonary hypertension, the prognosis for VFMR was significantly worse than for AFMR (HR 1.57, 95% CI 1.47 to 1.68 for all-cause and 1.73, 95% CI 1.60 to 1.88, p<0.001 for both). After further adjustment for LVEF, mortality rates were similar in VFMR and AFMR patients (HR 0.93, p=NS), though advancing age and pulmonary hypertension remained independently associated with prognosis. CONCLUSIONS: AFMR is a common cause of significant functional MR that predominantly affects elderly female patients with AF. Advancing age and pulmonary hypertension independently associated with survival in FMR. Prognosis was better in AFMR compared with VFMR; however, this difference was accounted for by LV systolic impairment and not by MR severity.

Echocardiographic Imaging in Transcatheter Structural Intervention: An AAE Review Paper.

Transcatheter structural heart intervention (TSHI) has gained popularity over the past decade as a means of cardiac intervention in patients with prohibitive surgical risks. Following the exponential rise in cases and devices developed over the period, there has been increased focus on developing the role of "structural imagers" amongst cardiologists. This review, as part of a growing initiative to develop the field of interventional echocardiography, aims to highlight the role of echocardiography in myriad TSHIs available within Asia. We first discuss the various echocardiography-based imaging modalities, including 3-dimensional echocardiography, fusion imaging, and intracardiac echocardiography. We then highlight a selected list of structural interventions available in the region-a combination of established interventions alongside novel approaches-describing key anatomic and pathologic characteristics related to the relevant structural heart diseases, before delving into various aspects of echocardiography imaging for each TSHI.

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.