Reference ranges of left ventricular structure and function assessed by contrast-enhanced cardiac MR and changes related to ageing and hypertension in a population-based study

Racial Differences in Age-Related Changes in Left Ventricular Structural and Functional Echocardiographic Measurements Among Healthy Japanese and American Participants - A Subanalysis of the World Alliance Society of Echocardiography Normal Values Study

BACKGROUND

Age-related changes in left ventricular (LV) structure and function lower the threshold for the onset of heart failure with preserved ejection fraction (HFpEF). LV parameters change also with race; however, the racial differences in age-related changes in LV parameters with and without adjustment for body mass index (BMI), heart rate (HR), and blood pressure (BP) remain unclear.

METHODS AND RESULTS

We performed a subanalysis of the World Alliance Society of Echocardiography Normal Values Study, an international cross-sectional study that examined normal echocardiographic values in 15 countries. The age-related changes in 2-dimensional echocardiographic derived parameters including LV size, systolic function, and mass, were compared between healthy Japanese (n=227) and healthy White (n=98) and Black (n=69) American participants. In men, age-related changes in all parameters did not differ significantly among races. However, compared with Japanese women, White American women had a smaller body surface area (BSA)-indexed LV volume, BSA-indexed LV internal dimension at end-systole, BSA-indexed LV stroke volume, and LV mass index to BSA, and a larger LV ejection fraction with age, even after adjusting for BMI, HR, and BP.

CONCLUSIONS

Age-related changes in LV structure and function, which are important for the pathophysiology of HFpEF, may differ by race. Therefore, future studies examining echocardiographic reference values for each age group in each race are needed.

Device-measured physical activity and cardiac structure by magnetic resonance

BACKGROUND AND AIMS

Although extreme cardiac adaptions mirroring phenotypes of cardiomyopathy have been observed in endurance athletes, adaptions to high levels of physical activity within the wider population are under-explored. Therefore, in this study, associations between device-measured physical activity and clinically relevant cardiac magnetic resonance volumetric indices were investigated.

METHODS

Individuals without known cardiovascular disease or hypertension were included from the UK Biobank. Cardiac magnetic resonance data were collected between 2015 and 2019, and measures of end-diastolic chamber volume, left ventricular (LV) wall thickness, and LV ejection fraction were extracted. Moderate-to-vigorous-intensity physical activity (MVPA), vigorous-intensity physical activity (VPA), and total physical activity were assessed via wrist-worn accelerometers.

RESULTS

A total of 5977 women (median age and MVPA: 62 years and 46.8 min/day, respectively) and 4134 men (64 years and 49.8 min/day, respectively) were included. Each additional 10 min/day of MVPA was associated with a 0.70 [95% confidence interval (CI): 0.62, 0.79] mL/m2 higher indexed LV end-diastolic volume (LVEDVi) in women and a 1.08 (95% CI: 0.95, 1.20) mL/m2 higher LVEDVi in men. However, even within the top decile of MVPA, LVEDVi values remained within the normal ranges [79.1 (95% CI: 78.3, 80.0) mL/m2 in women and 91.4 (95% CI: 90.1, 92.7) mL/m2 in men]. Associations with MVPA were also observed for the right ventricle and the left/right atria, with an inverse association observed for LV ejection fraction. Associations of MVPA with maximum or average LV wall thickness were not clinically meaningful. Results for total physical activity and VPA mirrored those for MVPA.

CONCLUSIONS

High levels of device-measured physical activity were associated with cardiac remodelling within normal ranges.

Estimate of the hydraulic force in the aging heart: a cardiovascular magnetic resonance imaging study

BACKGROUND

Coupling between left ventricle (LV) and left atrium (LA) plays a central role in the process of cardiac remodeling during aging and development of cardiac disease. The hydraulic force (HyF) is related to variation in size between LV and LA. The objectives of this study were to: (1) derive an estimate of left atrioventricular HyF using cine- Magnetic Resonance Imaging (MRI) in healthy subjects with a wide age range, and (2) study its relationship with age and conventional diastolic function parameters, as estimated by reference echocardiography.

METHODS

We studied 119 healthy volunteers (mean age 44 ± 17 years, 58 women) who underwent Doppler echocardiography and MRI on the same day. Conventional transmitral flow early (E) and late (A) LV filling peak velocities as well as mitral annulus diastolic longitudinal peak velocity (E') were derived from echocardiography. MRI cine SSFP images in longitudinal two and four chamber views were acquired, and analyzed using feature tracking (FT) software. In addition to conventional LV and LA strain measurements, FT-derived LV and LA contours were further used to calculate chamber cross-sectional areas. HyF was approximated as the difference between the LV and LA maximal cross-sectional areas in the diastasis phase corresponding to the lowest LV-LA pressure gradient. Univariate and multivariate analyses while adjusting for appropriate variables were used to study the associations between HyF and age as well as diastolic function and strain indices.

RESULTS

HyF decreased significantly with age (R²=0.34, p < 0.0001). In addition, HyF was significantly associated with conventional indices of diastolic function and LA strain: E/A: R²=0.24, p < 0.0001; E': R²=0.24, p < 0.0001; E/E': R²=0.12, p = 0.0004; LA conduit longitudinal strain: R²=0.27, p < 0.0001. In multivariate analysis, associations with E/A (R2 = 0.39, p = 0.03) and LA conduit strain (R2 = 0.37, p = 0.02) remained significant after adjustment for age, sex, and body mass index.

CONCLUSIONS

HyF, estimated using FT contours, which are primarily used to quantify LV/LA strain on standard cardiac cine MRI, varied significantly with age in association with subclinical changes in ventricular filling. Its usefulness in cohorts of patients with left heart disease to detect LV-LA uncoupling remains to be evaluated.

Cardiovascular Magnetic Resonance Reference Ranges From the Healthy Hearts Consortium

BACKGROUND

The absence of population-stratified cardiovascular magnetic resonance (CMR) reference ranges from large cohorts is a major shortcoming for clinical care.

OBJECTIVES

This paper provides age-, sex-, and ethnicity-specific CMR reference ranges for atrial and ventricular metrics from the Healthy Hearts Consortium, an international collaborative comprising 9,088 CMR studies from verified healthy individuals, covering the complete adult age spectrum across both sexes, and with the highest ethnic diversity reported to date.

METHODS

CMR studies were analyzed using certified software with batch processing capability (cvi42, version 5.14 prototype, Circle Cardiovascular Imaging) by 2 expert readers. Three segmentation methods (smooth, papillary, anatomic) were used to contour the endocardial and epicardial borders of the ventricles and atria from long- and short-axis cine series. Clinically established ventricular and atrial metrics were extracted and stratified by age, sex, and ethnicity. Variations by segmentation method, scanner vendor, and magnet strength were examined. Reference ranges are reported as 95% prediction intervals.

RESULTS

The sample included 4,452 (49.0%) men and 4,636 (51.0%) women with average age of 61.1 ± 12.9 years (range: 18-83 years). Among these, 7,424 (81.7%) were from White, 510 (5.6%) South Asian, 478 (5.3%) mixed/other, 341 (3.7%) Black, and 335 (3.7%) Chinese ethnicities. Images were acquired using 1.5-T (n = 8,779; 96.6%) and 3.0-T (n = 309; 3.4%) scanners from Siemens (n = 8,299; 91.3%), Philips (n = 498; 5.5%), and GE (n = 291, 3.2%).

CONCLUSIONS

This work represents a resource with healthy CMR-derived volumetric reference ranges ready for clinical implementation.

Cardiac remodelling in non-alcoholic fatty liver disease in the general population

BACKGROUND AND AIMS

Non-alcoholic fatty liver disease (NAFLD) is associated with increased risk for cardiovascular disease. Our study investigates the contribution of NAFLD to changes in cardiac structure and function in a general population.

METHODS

One thousand ninety-six adults (49.3% female) from the Study of Health in Pomerania underwent magnetic resonance imaging including cardiac and liver imaging. The presence of NAFLD by proton density fat fraction was related to left cardiac structure and function. Results were adjusted for clinical confounders using multivariable linear regression model.

RESULTS

The prevalence for NAFLD was 35.9%. In adjusted multivariable linear regression models, NAFLD was positively associated with higher left ventricular mass index (β = 0.95; 95% confidence interval (CI): 0.45; 1.45), left ventricular concentricity (β = 0.043; 95% CI: 0.031; 0.056), left ventricular end-diastolic wall thickness (β = 0.29; 95% CI: 0.20; 0.38), left atrial end-diastolic volume index (β = 0.67; 95% CI: 0.01; 1.32) and inversely associated with left ventricular end-diastolic volume index (β = -0.78; 95% CI: -1.51; -0.05). When stratified by sex, we only found significant positive associations of NAFLD with left ventricular mass index, left atrial end-diastolic volume index, left ventricular cardiac output and an inverse association with global longitudinal strain in women. In contrast, men had an inverse association with left ventricular end-diastolic volume index and left ventricular stroke volume. Higher liver fat content was stronger associated with higher left ventricular mass index, left ventricular concentricity and left ventricular end-diastolic wall thickness.

CONCLUSION

NAFLD is associated with cardiac remodelling in the general population showing sex specific patterns in cardiac structure and function.

Reference Ranges of Ventricular Morphology and Function in Healthy Chinese Adults: A Multicenter 3 T MRI Study

BACKGROUND

Magnetic resonance imaging (MRI) reference ranges for ventricular morphology and function in the Chinese population are lacking.

PURPOSE

To establish the MRI reference ranges of left and right ventricular (LV and RV) morphology and function based on a large multicenter cohort.

STUDY TYPE

Prospective.

POPULATION

One thousand and twelve healthy Chinese Han adults.

FIELD STRENGTH/SEQUENCE

Balanced steady-state free procession cine sequence at 3.0 T.

ASSESSMENT

Biventricular end-diastolic, end-systolic, stroke volume, and ejection fraction (EDV, ESV, SV, and EF), LV mass (LVM), end-diastolic and end-systolic dimension (LVEDD and LVESD), anteroseptal wall thickness (AS), and posterolateral wall thickness (PL) were measured. Body surface area (BSA) and height were used to index biventricular parameters. Parameters were compared between age groups and sex.

STATISTICAL TESTS

Independent-samples t-tests or Mann-Whitney U test to compare mean values between sexes; ANOVA or Kruskal-Wallis test to compare mean values among age groups; linear regression to assess the relationships between cardiac parameters and age (correlation coefficient, r). A P value <0.05 was considered statistically significant.

RESULTS

The biventricular volumes, LVM, LVEDD, RVEDV/LVEDV ratio, LVESD, AS, and PL were significantly greater in males than in females, even after indexing to BSA or height, while LVEF and RVEF were significantly lower in males than in females. For both sexes, age was significantly negatively correlated with biventricular volumes (male and female: LVEDV [r = -0.491; r = -0.373], LVESV [r = -0.194; r = -0.184], RVEDV [r = -0.639; r = -0.506], RVESV [r = -0.270; r = -0.223]), with similar correlations after BSA normalization. LVEF (r = 0.043) and RVEF (r = 0.033) showed a significant correlation with age in females, but not in males (P = 0.889; P = 0.282).

DATA CONCLUSION

MRI reference ranges for biventricular morphology and function in Chinese adults are presented and show significant associations with age and sex.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 2.

Left ventricular hypertrophy as a risk factor for accelerated brain aging: Results from the Study of Health in Pomerania

Previous studies provided evidence for the importance of cardiac structure abnormalities, in particular greater left ventricular (LV) mass, for brain aging, but longitudinal studies are lacking to date. We included 926 individuals (median age 48 years; 53% women) from the TREND cohort of the Study of Health in Pomerania (SHIP) without reduced ejection fraction or a history of myocardial infarction. LV mass index (LVMI) was determined by echocardiography at baseline. Brain morphometric measurements were derived from magnetic resonance images at baseline and 7-year follow-up. Direct effects of baseline LVMI on brain morphometry at follow-up were estimated using linear regression models with adjustment for baseline brain morphometry. At baseline, median LVMI was 40 g/m2.7 and 241 individuals (26%) met the criterion of LV hypertrophy. After correction for multiple testing, baseline LVMI was directly associated with reduced global cortical thickness and increased cortical brain age at follow-up independent from hypertension and blood pressure. Exposure-outcome relations were nonlinear and significantly stronger in the upper half of the exposure distribution. Specifically, an increase in baseline LVMI from the 50% quantile to the 95% quantile was associated additional 2.7 years (95% confidence interval = [1.5 years, 3.8 years]) of cortical brain age at follow-up. Additional regional analyses yielded bilateral effects on multiple frontal cortical regions. Our findings highlight the role of cardiac structure in brain aging. LVMI constitutes an easily measurable marker that might help to identify persons at risk for cognitive impairment and dementia.

Sphingosine-1-phosphate levels are inversely associated with left ventricular and atrial chamber volume and cardiac mass in men : The Study of Health in Pomerania (SHIP)

AIMS

Sphingosine-1-phosphate (S1P) is a signaling lipid, which is involved in several cellular processes including cell growth, proliferation, migration and apoptosis. The associations of serum S1P levels with cardiac geometry and function are still not clear. We investigated the associations of S1P with cardiac structure and systolic function in a population-based sample.

METHODS AND RESULTS

We performed cross-sectional analyses of 858 subjects (467 men; 54.4%), aged 22 to 81 years, from a sub-sample of the population-based Study of Health in Pomerania (SHIP-TREND-0). We analyzed the associations of serum S1P with structural and systolic function left ventricular (LV) and left atrial (LA) parameters as determined by magnetic resonance imaging (MRI) using sex-stratified multivariable-adjusted linear regression models. In men, MRI data showed that a 1 µmol/L lower S1P concentration was associated with an 18.1 mL (95% confidence interval [CI] 3.66-32.6; p = 0.014) larger LV end-diastolic volume (LVEDV), a 0.46 mm (95% CI 0.04-0.89; p = 0.034) greater LV wall thickness (LVWT) and a 16.3 g (95% CI 6.55-26.1; p = 0.001) higher LV mass (LVM). S1P was also associated with a 13.3 mL/beat (95% CI 4.49-22.1; p = 0.003) greater LV stroke volume (LVSV), an 18.7 cJ (95% CI 6.43-30.9; p = 0.003) greater LV stroke work (LVSW) and a 12.6 mL (95% CI 1.03-24.3; p = 0.033) larger LA end-diastolic volume (LAEDV). We did not find any significant associations in women.

CONCLUSIONS

In this population-based sample, lower levels of S1P were associated with higher LV wall thickness and mass, larger LV and LA chamber sizes and greater stroke volume and work of the LV in men, but not in women. Our results indicate that lower levels of S1P were associated with parameters related with cardiac geometry and systolic function in men, but not in women.

J wave syndromes in patients with spinal and bulbar muscular atrophy

BACKGROUND

Males with X-linked recessive spinobulbar muscular atrophy (SBMA) are reported to die suddenly and a Brugada electrocardiography (ECG) pattern may be present. A hallmark of this pattern is the presence of ST segment elevations in right precordial leads associated with an increased risk of sudden cardiac death.

OBJECTIVE

We aimed to detect subtle myocardial abnormalities using ECG and cardiovascular magnetic resonance imaging (CMR) in patients with SBMA.

METHODS

30 SBMA patients (55.7 ± 11.9 years) and 11 healthy male controls underwent 12-lead ECGs were recorded using conventional and modified chest leads. CMR included feature-tracking strain analysis, late gadolinium enhancement and native T1 and T2 mapping.

RESULTS

Testosterone levels were increased in 6/29 patients. Abnormal ECGs were recorded in 70%, consisting of a Brugada ECG pattern, early repolarization or fragmented QRS. Despite normal left ventricular ejection fraction (66 ± 5%), SBMA patients exhibited more often left ventricular hypertrophy as compared to controls (34.5% vs 20%). End-diastolic volumes were smaller in SBMA patients (left ventricular volume index 61.7 ± 14.7 ml/m² vs. 79.1 ± 15.5 ml/m²; right ventricular volume index 64.4 ± 16.4 ml/m² vs. 75.3 ± 17.5 ml/m²). Tissue characterization with T1-mapping revealed diffuse myocardial fibrosis in SBMA patients (73.9% vs. 9.1%, device-specific threshold for T1: 1030 ms).

CONCLUSION

SBMA patients show abnormal ECGs and structural abnormalities, which may explain an increased risk of sudden death. These findings underline the importance of ECG screening, measurement of testosterone levels and potentially CMR imaging to assess cardiac risk factors.

SHIP-MR and Radiology: 12 Years of Whole-Body Magnetic Resonance Imaging in a Single Center

The Study of Health in Pomerania (SHIP), a population-based study from a rural state in northeastern Germany with a relatively poor life expectancy, supplemented its comprehensive examination program in 2008 with whole-body MR imaging at 1.5 T (SHIP-MR). We reviewed more than 100 publications that used the SHIP-MR data and analyzed which sequences already produced fruitful scientific outputs and which manuscripts have been referenced frequently. Upon reviewing the publications about imaging sequences, those that used T1-weighted structured imaging of the brain and a gradient-echo sequence for R2* mapping obtained the highest scientific output; regarding specific body parts examined, most scientific publications focused on MR sequences involving the brain and the (upper) abdomen. We conclude that population-based MR imaging in cohort studies should define more precise goals when allocating imaging time. In addition, quality control measures might include recording the number and impact of published work, preferably on a bi-annual basis and starting 2 years after initiation of the study. Structured teaching courses may enhance the desired output in areas that appear underrepresented.

Lower Cardiorespiratory Fitness Is Associated With Right Ventricular Geometry and Function - The Sedentary's Heart: SHIP

Background

Lower cardiorespiratory fitness (CRF) is associated with an increased risk for cardiovascular disease. However, very little information is available about the association between lower CRF and right ventricular (RV) remodeling. We investigated the relationship between CRF and RV structure and function in a large, aging, and largely sedentary adult population–based cohort.

Methods and Results

We used cross‐sectional data of 2844 subjects (1486 women; median age, 51 years; interquartile range, 40–62 years) from the population‐based cohort SHIP (Study of Health in Pomerania) with echocardiography, of which 941 also had cardiac magnetic resonance imaging. We analyzed the associations of peak oxygen uptake with RV parameters determined by both imaging techniques using multivariable‐adjusted linear regression models. In echocardiography, a 1 L/min lower peak oxygen uptake was associated with a 1.18 mm (95% CI, 0.66–1.71; P<0.001) smaller RV end‐diastolic diameter and a 1.41 mm (95% CI, 0.90–1.92; P<0.001) narrower RV end‐diastolic outflow tract diameter. Similarly, using cardiac magnetic resonance imaging measurements, a 1 L/min lower peak oxygen uptake was associated with a 23.5 mL (95% CI, 18.7–28.4; P<0.001) smaller RV end‐diastolic volume, a 13.0 mL (95% CI, 9.81–16.2; P<0.001) lower RV end‐systolic volume, and a 10.7 mL/beat (95% CI, 8.10–13.3; P<0.001) lower RV stroke volume.

Conclusions

Our results indicate a significant association between CRF and RV remodeling. Lower CRF was associated with smaller RV chamber and lower RV systolic function, stroke volume, and cardiac output.

Lower muscular strength is associated with smaller left and right chambers and lower cardiac mass in the general population - The Sedentary's Heart

BACKGROUND

The cardiac muscle has the ability to adapt to different loading conditions. We analyzed the associations of the age-related decreasing handgrip strength (HGS), a marker of muscular fitness, on cardiac structure and function in a community-based sample.

METHODS

We performed cross-sectional analyses of 4646 subjects (2554 women; 55.0%) aged 20 to 93 years from two independent cohorts of the Study of Health in Pomerania (SHIP-2 and SHIP-TREND-0). We analyzed the associations of HGS with structural and functional left and right ventricular (LV and RV) and left atrial (LA) parameters as determined by echocardiography and magnetic resonance imaging (MRI) as well with log-transformed NT-proBNP values using multivariable-adjusted linear regression models.

RESULTS

MRI data showed that a 1 kg lower HGS was associated with a 0.40 mL (95% confidence interval: 0.26 to 0.54; p < 0.001) lower LV end-diastolic volume, a 0.011 mm (0.005 to 0.018; p = 0.001) lower LV wall-thickness, a 0.59 g (0.43 to 0.75; p < 0.001) lower LV mass, a 0.58 mL/beat (0.43 to 0.74; p < 0.001) lower LV stroke volume, a 0.03 L/min (0.02 to 0.04; p < 0.001) lower LV cardiac output, a 0.48 mL (0.27 to 0.68; p < 0.001) lower LA end-diastolic volume, and a 1.02 mL (0.71 to 1.32) lower RV end-diastolic volume. Similar findings were observed for echocardiographic parameters. Moreover, lower HGS was associated with higher echocardiographic LV diastolic stiffness and NT-proBNP levels.

CONCLUSIONS

In this large population-based sample, lower muscular fitness as assessed by HGS was associated with lower LV wall thickness and mass as well as with smaller chamber size, stroke volume and cardiac output of the LV, LA and RV. Moreover, HGS was inversely related to LV diastolic stiffness and NT-proBNP values. These outcomes might demonstrate the effects of an aging-related decrease in physical activity and lower muscular fitness on the heart - "the sedentary's heart".

Biventricular Morphology and Function Reference Values Derived From a Large Sample of Healthy Chinese Adults by Magnetic Resonance Imaging

Background: Quantification of cardiac structure and function is essential for diagnostic interpretation and clinical decision making. We sought to establish cardiovascular magnetic resonance (CMR) reference values of left and right ventricular (LV and RV) morphology and function based on a large sample of healthy Chinese adults. Methods: Five hundred fifty validated healthy Chinese adults (aged 21-70 years; 323 men) free of hypertension, diabetes, and obesity were included in this study. All the subjects were stratified by gender (men and women) and age decades. On cine CMR, measurements of biventricular end-diastolic, end-systolic, and stroke volumes (EDV, ESV, and SV), ejection fraction (EF), and end-diastolic LV wall thickness (LVWT) and mass (LVM) were obtained. Results: Men had greater LVEDV (111.6 ± 19.8 vs. 94.6 ± 15.6 ml), LVESV (36.5 ± 9.8 vs. 28.2 ± 7.9 ml), LVM (121.1 ± 19.9 vs. 86.1 ± 14.5 g), global end-diastolic LVWT (8.1 ± 1.1 vs. 6.7 ± 1.0 mm), RVEDV (128.0 ± 23.6 vs. 101.7 ± 17.0 ml), and RVESV (53.5 ± 13.7 vs. 36.8 ± 8.9 ml), while women had greater LVEF (67.5 ± 5.4 vs. 70.4 ± 5.7%) and RVEF (58.5 ± 5.2 vs. 64.0 ± 5.3%) (all p < 0.001). For both men and women, age was negatively correlated with LVEDV (r = -0.31 and r = -0.32), LVESV (r = -0.37 and r = -0.47), RVEDV (r = -0.31 and r = -0.29), and RVESV (r = -0.33 and r = -0.44), while it was positively correlated with LVEF (r = 0.28 and r = 0.43) and RVEF (r = 0.28 and r = 0.41) (all p < 0.001). Aging was associated with increasing global end-diastolic LVWT and LVM/LVEDV in both sexes (all p < 0.001). Older age was associated with increasing LVM only in women (r = 0.36, p < 0.001), not in men (r = 0.05, p = 0.359). Conclusions: We systematically provide age-, sex-, and body size-specific CMR reference values for biventricular morphology and function based on a large sample of healthy Chinese adults. Biventricular structure and function are significantly associated with age and sex.

Variation in left ventricular cardiac magnetic resonance normal reference ranges: systematic review and meta-analysis

AIMS

To determine population-related and technical sources of variation in cardiac magnetic resonance (CMR) reference ranges for left ventricular (LV) quantification through a formal systematic review and meta-analysis.

METHODS AND RESULTS

This study is registered with the International Prospective Register of Systematic Reviews (CRD42019147161). Relevant studies were identified through electronic searches and assessed by two independent reviewers based on predefined criteria. Fifteen studies comprising 2132 women and 1890 men aged 20-91 years are included in the analysis. Pooled LV reference ranges calculated using random effects meta-analysis with inverse variance weighting revealed significant differences by age, sex, and ethnicity. Men had larger LV volumes and higher LV mass than women [LV end-diastolic volume (mean difference = 6.1 mL/m2, P-value = 0.014), LV end-systolic volume (MD = 4 mL/m2, P-value = 0.033), LV mass (mean difference = 12 g/m2, P-value = 7.8 × 10-9)]. Younger individuals had larger LV end-diastolic volumes than older ages (20-40 years vs. ≥65 years: women MD = 14.0 mL/m2, men MD = 14.7 mL/m2). East Asians (Chinese, Korean, Singaporean-Chinese, n = 514) had lower LV mass than Caucasians (women: MD = 6.4 g/m2, P-value = 0.016; men: MD = 9.8 g/m2, P-value = 6.7 × 10-5). Between-study heterogeneity was high for all LV parameters despite stratification by population-related factors. Sensitivity analyses identified differences in contouring methodology, magnet strength, and post-processing software as potential sources of heterogeneity.

CONCLUSION

There is significant variation between CMR normal reference ranges due to multiple population-related and technical factors. Whilst there is need for population-stratified reference ranges, limited sample sizes and technical heterogeneity precludes derivation of meaningful unified ranges from existing reports. Wider representation of different populations and standardization of image analysis is urgently needed to establish such reference distributions.

Age- and gender-related reference values of cardiac morphology and function in cardiovascular magnetic resonance

Cardiovascular magnetic resonance (CMR) is the reference standard for the quantitative assessment of cardiac morphology and function. The aim of the study was to determine age- and gender-related reference values for cardiac morphology and function according to current recommendations. 454 healthy volunteers (235 men, median age 52.0 (44.0-59.0) years) underwent a standard CMR scan and were divided into six groups of nearly equal size with regard to sex (male, female) and age (21-47 years, 48-57 years, 58-84 years). Left ventricular end-diastolic (LV-EDV) and end-systolic (LV-ESV) volumes and LV mass (LV-M) were measured at end-diastole and end-systole in steady-state free precession series with including papillary muscles and trabecular tissue in the LV-M. Absolute and indexed volumetric parameters were significantly different between gender groups with higher values in men compared to women (all p < 0.001). Furthermore, a significant age-dependent decline could be observed for left ventricular and right ventricular volumes (all p < 0.001), while LV-M did not show differences between the different age-groups. Parameters of longitudinal function for the left and right ventricle were higher in female compared to male subjects with a significant age-dependent decline. We provided normal values for cardiac volumes, function, and mass derived in accordance with current guidelines from a large population of healthy subjects, which can be implemented in clinical routine as a standard of reference.

Reference ranges ("normal values") for cardiovascular magnetic resonance (CMR) in adults and children: 2020 update

Cardiovascular magnetic resonance (CMR) enables assessment and quantification of morphological and functional parameters of the heart, including chamber size and function, diameters of the aorta and pulmonary arteries, flow and myocardial relaxation times. Knowledge of reference ranges ("normal values") for quantitative CMR is crucial to interpretation of results and to distinguish normal from disease. Compared to the previous version of this review published in 2015, we present updated and expanded reference values for morphological and functional CMR parameters of the cardiovascular system based on the peer-reviewed literature and current CMR techniques. Further, databases and references for deep learning methods are included.

Artificial Intelligence and Big Data

Medical images play an important role in ophthalmology and radiology. Medical image analysis has greatly benefited from the application of "deep learning" techniques in clinical and experimental radiology. Clinical applications and their relevance for radiological imaging in ophthalmology are presented.

Glucose and insulin levels are associated with arterial stiffness and concentric remodeling of the heart

BACKGROUND

Mortality attributable to heart failure remains high. The prevalence of heart failure in patients with diabetes mellitus ranges from 19 to 26%. It is estimated that up to 21.1 million adults in the United States have diagnosed diabetes mellitus and around 80.8 million have impaired fasting glucose. We investigated the associations of fasting glucose (FG) and fasting insulin (FI), the homeostasis model assessment-insulin resistance index (HOMA-IR) and 2-h postload glucose (2HG) and insulin (2HI) with parameters of left ventricular geometry and function and arterial stiffness determined by magnetic resonance imaging in individuals without diagnosed type 2 diabetes.

METHODS

Cross-sectional analyses of 1001 individuals (453 women, 45.3%), aged 21 to 80 years, from two independent population-based studies, the Study of Health in Pomerania (SHIP-TREND-0) and KORA FF4 Study. FG, FI, HOMA-IR, 2HG and 2HI, as well as glucose tolerance categories, were analyzed for associations with heart and arterial parameters using multivariable-adjusted linear regression models.

RESULTS

In total, 390 individuals (39%) had prediabetes (isolated impaired fasting glucose, isolated glucose tolerance or both), and 49 (4.9%) were found to have unknown type 2 diabetes. In the multivariable-adjusted analysis, positive linear associations of FG, FI, HOMA-IR, 2HG and 2HI with arterial stiffness index and left ventricular wall-thickness and concentricity and inverse linear associations with left ventricular end-diastolic volume were observed. A 1 mmol/l higher FG was associated with a 1.18 ml/m^2.7 (1.80 to 0.57; p < 0.001) lower left ventricular end-diastolic volume index, a 0.042 mm/m^2.7 (0.014 to 0.070) higher left ventricular wall-thickness index, a 0.12 mmHg m^2.7/ml (0.06 to 0.17; p < 0.001) greater arterial stiffness index and a 0.037 g/ml (0.018 to 0.056; p < 0.001) higher left ventricular concentricity.

CONCLUSIONS

Our findings suggest that higher glucose levels in the prediabetic range and insulin resistance might lead to higher arterial stiffness and concentric remodeling of the heart.