Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
6,862
result(s) for
"Left ventricular volume"
Sort by:
Left ventricular and left atrial volume ratio assessed by three‐dimensional echocardiography: Novel indices for evaluating age‐related change in left heart chamber size
by
Nabeshima, Yosuke
,
Otani, Kyoko
,
Kitano, Tetsuji
in
3D echocardiography
,
Ageing and Degeneration
,
Aging
2019
We hypothesized that left ventricular and left atrial volume ratio (LVLAVR) assessed by three‐dimensional echocardiography (3DE) reflects age‐ and gender‐related change in left chamber size. We aimed to (1) determine the reference values of LVLAVR, (2) investigate their age and gender dependency, and (3) clarify which anthropometric and echocardiography parameters are closely associated with these indices. Both left ventricular (LV) and left atrial (LA) volume curves were obtained using 3DE speckle tracking analytical software, and the LVLAVR curve throughout one cardiac cycle was created, from which LVLAVR at ventricular end‐diastole and at ventricular end‐systole were determined in 313 healthy subjects (age, 20–85 years; 51% men). The mean values of LVLAVR at ventricular end‐diastole and ventricular end‐systole in male subjects were 5.74 ± 1.54 and 1.37 ± 0.35, respectively. Corresponding values in female subjects were significantly lower (5.20 ± 1.47, p = .003 and 1.13 ± 0.29, p < .001) than the values in male subjects. LVLAVR at ventricular end‐diastole step wisely decreased to advanced aging, and had a highest F ratio compared with other left chamber volumetric parameters in both genders. LV mass and LA ejection fraction were significantly associated with LVLAVR at ventricular end‐diastole. In contrast, LV mass and LV ejection fraction were significantly coupled with LVLAVR at ventricular end‐systole. This study provides the reference values for LVLAVR from a relatively large number of healthy subjects. LVLAVR may be a sensitive parameter to reflect age‐ and gender‐related change in LV and LA volumes. Further studies should be required to determine its clinical usefulness over traditional echocardiography parameters in various cardiovascular diseases. To our best knowledge, this study is the first to investigate the left ventricular and left atrial volume ratio (LVLAVR) using three‐dimensional echocardiography. We determined age‐ and sex‐specific reference values of LVLAVR at end‐diastole and end‐systole from a relatively large number of healthy subjects. Detailed assessment of LVLAVR clarifies the temporal status of LV−LA coupling at different time points of the cardiac cycle, and thus, would provide further insights for LV−LA coupling.
Journal Article
Validating real-time three-dimensional echocardiography against cardiac magnetic resonance, for the determination of ventricular mass, volume and ejection fraction: a meta-analysis
by
Dissabandara, Thilini
,
Sun, Jing
,
wood, Mark
in
Cardiovascular diseases
,
Disease
,
Echocardiography
2024
IntroductionReal-time three-dimensional echocardiography (RT3DE) is currently being developed to overcome the challenges of two-dimensional echocardiography, as it is a much cheaper alternative to the gold standard imaging method, cardiac magnetic resonance (CMR). The aim of this meta-analysis is to validate RT3DE by comparing it to CMR, to ascertain whether it is a practical imaging method for routine clinical use.MethodsA systematic review and meta-analysis method was used to synthesise the evidence and studies published between 2000 and 2021 were searched using a PRISMA approach. Study outcomes included left ventricular end-systolic volume (LVESV), left ventricular end-diastolic volume (LVEDV), left ventricular ejection fraction (LVEF), left ventricular mass (LVM), right ventricular end-systolic volume (RVESV), right ventricular end-diastolic volume (RVEDV) and right ventricular ejection fraction (RVEF). Subgroup analysis included study quality (high, moderate), disease outcomes (disease, healthy and disease), age group (50 years old and under, over 50 years), imaging plane (biplane, multiplane) and publication year (2010 and earlier, after 2010) to determine whether they explained the heterogeneity and significant difference results generated on RT3DE compared to CMR.ResultsThe pooled mean differences for were − 5.064 (95% CI − 10.132, 0.004, p > 0.05), 4.654 (95% CI − 4.947, 14.255, p > 0.05), − 0.783 (95% CI − 5.630, 4.065, p > 0.05, − 0.200 (95% CI − 1.215, 0.815, p > 0.05) for LVEF, LVM, RVESV and RVEF, respectively. We found no significant difference between RT3DE and CMR for these variables. Although, there was a significant difference between RT3DE and CMR for LVESV, LVEDV and RVEDV where RT3DE reports a lower value. Subgroup analysis indicated a significant difference between RT3DE and CMR for studies with participants with an average age of over 50 years but no significant difference for those under 50. In addition, a significant difference between RT3DE and CMR was found in studies using only participants with cardiovascular diseases but not in those using a combination of diseased and healthy participants. Furthermore, for the variables LVESV and LVEDV, the multiplane method shows no significant difference between RT3DE and CMR, as opposed to the biplane showing a significant difference. This potentially indicates that increased age, the presence of cardiovascular disease and the biplane analysis method decrease its concordance with CMR.ConclusionThis meta-analysis indicates promising results for the use of RT3DE, with limited difference to CMR. Although in some cases, RT3DE appears to underestimate volume, ejection fraction and mass when compared to CMR. Further research is required in terms of imaging method and technology to validate RT3DE for routine clinical use.
Journal Article
Effects of carvedilol on left ventricular remodelling in chronic stable heart failure: a cardiovascular magnetic resonance study
by
Coats, A J S
,
Rahman, S L
,
Cleland, J G F
in
Adrenergic beta-Antagonists - therapeutic use
,
Aged
,
Beta blockers
2004
Background: The ability of β blockers to improve left ventricular function has been demonstrated, but data on the effects on cardiac remodelling are limited. Objective: To investigate, using cardiovascular magnetic resonance (CMR), the effects of carvedilol on left ventricular remodelling in patients with chronic stable heart failure and left ventricular systolic dysfunction caused by coronary artery disease. Design: Randomised, double blind, placebo controlled study. Setting: Chronic stable heart failure. Patients and intervention: 34 patients with chronic stable heart failure and left ventricular systolic function taking part in the CHRISTMAS trial (double blind carvedilol v placebo) underwent CMR before randomisation and after six months of treatment. Main outcome measure: Left ventricular remodelling at six months. Results: The carvedilol and placebo groups were well balanced at baseline, with no significant intergroup differences. Over the study period, there was a significant reduction in end systolic volume index (ESVI) and end diastolic volume index (EDVI) between the carvedilol and the placebo group (carvedilol −9 v placebo +3 ml/m2, p = 0.0004; carvedilol −8 v placebo 0 ml/m2, p = 0.05). The ejection fraction increased significantly between the groups (carvedilol +3% v placebo −2%, p = 0.003). Conclusions: Treatment of chronic stable heart failure with carvedilol results in significant improvement in left ventricular volumes and function. These effects might contribute to the benefits of carvedilol on mortality and morbidity in patients with chronic heart failure.
Journal Article
Impact of mesenchymal stem cell therapy on cardiac function and outcomes in acute myocardial infarction: A meta-analysis of clinical studies
by
Tian, Qingqing
,
Deng, Yan
,
Zhao, Mei
in
Cardiovascular disease
,
Cell therapy
,
Clinical outcomes
2025
This meta-analysis evaluated the efficacy of mesenchymal stem cell (MSC) treatment on cardiovascular function and major adverse cardiac events (MACE) in patients with acute myocardial infarction (AMI) at various follow-up intervals. Clinical studies comparing MSC therapy with control treatments for AMI were identified from databases including Cochrane, Web of Science, PubMed, Embase, CNKI, and Wanfang, covering publications up to August 2024. Data analysis was conducted using Review Manager 5.4 software. MSC treatment significantly improved left ventricular ejection fraction (LVEF) compared to controls at follow-up intervals <6 months (MD = 3.42; P < 0.0001), 6 months (MD = 4.15; P = 0.006), and 12 months (MD = 2.77; P = 0.006). However, no significant effect on LVEF was observed after 12 months (MD = 3.50; P = 0.17). MSC therapy did not significantly affect left ventricular end-diastolic volume (LVEDV) at any interval. Left ventricular end-systolic volume (LVESV) significantly decreased only within the first 6 months (MD = −11.35; P = 0.11) but not at subsequent follow-ups. Wall motion score index (WMSI) significantly improved at <6 months (MD = −0.06; P < 0.0001), 6 months (MD = −0.04; P = 0.006), and >12 months (MD = −0.03; P = 0.02). However, the improvement at 12 months was borderline significant (MD = −0.06; P = 0.06). MSC therapy showed no significant reduction in MACE (odds ratio [OR] = 1.61; P = 0.10). Subgroup analyses indicated intracoronary MSC administration notably improved LVEF (MD = 4.27; P < 0.0001), while intravenous MSC administration showed no significant effect. Neither administration route significantly affected MACE outcomes. No publication bias was detected. In conclusion, MSC therapy significantly enhances LVEF and WMSI within the first 12 months post-AMI, with intracoronary administration showing greater efficacy than intravenous delivery. However, MSC treatment did not significantly reduce MACE incidence. Further rigorous clinical trials are needed to confirm these findings.
Graphical Abstract
Journal Article
Diastolic dysfunction is associated with poor survival in patients with cirrhosis with transjugular intrahepatic portosystemic shunt
by
Meregaglia, Daniele
,
Visentin, Stefania
,
Nicolini, Antonio
in
Adult
,
Aged
,
atrial maximal filling velocity
2007
Background: Transjugular intrahepatic portosystemic shunt (TIPS) is a treatment for portal hypertension-related complications. Accurate prediction of the outcome of patients treated with TIPS is important, because some patients have very short survival. Diastolic dysfunction is frequently observed in patients with cirrhosis. Aim: To investigate whether or not diastolic dysfunction can predict the outcome after TIPS. Methods: Echocardiography with Doppler exploration was performed before and 28 days after TIPS insertion in 32 patients with cirrhosis. Several echocardiographic measures, including the early maximal ventricular filling velocity/late filling velocity (E/A) ratio as indicative of diastolic function, as well as laboratory, clinical and demographic variables were evaluated as predictors of survival. Results: Univariate analysis revealed that the presence of diastolic dysfunction observed 28 days after TIPS (E/A ratio ⩽1) and baseline model of end-stage liver disease score were related to survival. Multivariate analysis identified diastolic dysfunction as an independent predictor of death (RR 8.9, 95% CI 1.9 to 41.5, p = 0.005). During the first year of follow–up, six out of 10 patients with an E/A ratio ⩽1 died, whereas all 22 patients with E/A ratio >1 survived. Conclusions: Diastolic dysfunction estimated using E/A ratio is a promising predictor of death in patients with cirrhosis who are treated with TIPS.
Journal Article
Finite state machine implementation for left ventricle modeling and control
by
Bergeron, Clint A.
,
Taylor, Charles E.
,
King, Jacob M.
in
Architectural engineering
,
Architecture
,
Biomaterials
2019
Background
Simulation of a left ventricle has become a critical facet of evaluating therapies and operations that interact with cardiac performance. The ability to simulate a wide range of possible conditions, changes in cardiac performance, and production of nuisances at transition points enables evaluation of precision medicine concepts that are designed to function through this spectrum. Ventricle models have historically been based on biomechanical analysis, with model architectures constituted of continuous states and not conducive to deterministic processing. Producing a finite-state machine governance of a left ventricle model would enable a broad range of applications: physiological controller development, experimental left ventricle control, and high throughput simulations of left ventricle function.
Methods
A method for simulating left ventricular pressure-volume control utilizing a preload, afterload, and contractility sensitive computational model is shown. This approach uses a logic-based conditional finite state machine based on the four pressure-volume phases that describe left ventricular function. This was executed with a physical system hydraulic model using MathWorks’ Simulink
®
and Stateflow tools.
Results
The approach developed is capable of simulating changes in preload, afterload, and contractility in time based on a patient’s preload analysis. Six pressure–volume loop simulations are presented to include a base-line, preload change only, afterload change only, contractility change only, a clinical control, and heart failure with normal ejection fraction. All simulations produced an error of less than 1 mmHg and 1 mL of the absolute difference between the desired and simulated pressure and volume set points. The acceptable performance of the fixed-timestep architecture in the finite state machine allows for deployment to deterministic systems, such as experimental systems for validation.
Conclusions
The proposed approach allows for personalized data, revealed through an individualized clinical pressure–volume analysis, to be simulated in silico. The computational model architecture enables this control structure to be executed on deterministic systems that govern experimental left ventricles. This provides a mock circulatory system with the ability to investigate the pathophysiology for a specific individual by replicating the exact pressure–volume relationship defined by their left ventricular functionality; as well as perform predictive analysis regarding changes in preload, afterload, and contractility in time.
Journal Article
The effect of empagliflozin on cardiac function and structure in patients with heart failure with reduced ejection fraction: a systematic review and meta-analysis
by
Yang, Cui Bing
,
Nan, Geli
,
Jia, Zhi Kun
in
cardiac function
,
cardiac structure
,
Ejection fraction
2025
Empagliflozin was shown to improve the clinical outcomes of cardiovascular diseases; however, its effects on cardiac structure and cardiac remodeling in patients with heart failure remain controversial to some extent.
We conducted this meta-analysis to compare the effect of empagliflozin with placebo on cardiac structure and function among patients with heart failure.
PubMed, Scopus, Web of Science, and the Cochrane Library were systematically searched from inception to December 20, 2024, to identify randomized controlled trials comparing the effects of empagliflozin with placebo on cardiac structure and function in patients with heart failure. A random-effects model (DerSimonian-Laird) was employed to pool data.
Four studies with 234 individuals in the empagliflozin group and 231 individuals in the placebo group were included. Compared to placebo, empagliflozin 10 (mg/day) significantly increased left ventricular ejection fraction (LVEF) (WMD 2.96%, 95% CI (0.84, 5.09),
= 85.28%), decreased left ventricular (LV) end-diastolic volume (WMD -17.05 ml, 95% CI (-23.68, -10.42),
= 13.88%), LV end-diastolic volume index (WMD -7.59 ml/m
, 95% CI (-10.08, -5.10),
= 0.00%), LV end-systolic volume (WMD -15.59 ml, 95% CI (-25.89, -5.28),
= 74.69%), LV end-systolic volume index (WMD -6.68 ml/m
, 95% CI (-7.95, -5.41),
= 0.00%), and left atrial volume index (WMD -2.16 ml/m
, 95% CI (-4.21, -0.10),
= 0.00%), but did not significantly change LV mass (WMD -11.66 g, 95% CI (-30.54, 7.22),
= 90.02%) and LV mass index (WMD -4.01 g/m
, 95% CI (-10.94, 2.92),
= 64.29%).
Empagliflozin can significantly improve myocardial function and prevent myocardial remodeling in patients with heart failure.
Journal Article
Normative ranges of biventricular volumes and function in healthy term newborns
2023
BackgroundCardiovascular magnetic resonance (CMR) is increasingly used in newborns with congenital heart disease. However, reporting on ventricular volumes and mass is hindered by an absence of normative data in this population.Design/methodsHealthy term (37–41 weeks gestation) newborns underwent non-sedated, free-breathing CMR within the first week of life using the ‘feed and wrap’ technique. End-diastolic volume (EDV), end-systolic volume (ESV) stroke volume (SV) and ejection fraction (EF) were calculated for both left ventricle (LV) and right ventricle (RV). Papillary muscles were separately contoured and included in the myocardial volume. Myocardial mass was calculated by multiplying myocardial volume by 1.05 g/ml. All data were indexed to weight and body surface area (BSA). Inter-observer variability (IOV) was performed on data from 10 randomly chosen infants.ResultsTwenty healthy newborns (65% male) with a mean (SD) birth weight of 3.54 (0.46) kg and BSA of 0.23 (0.02) m2 were included. Normative LV parameters were indexed EDV 39.0 (4.1) ml/m2, ESV 14.5 (2.5) ml/m2 and ejection fraction (EF) 63.2 (3.4)%. Normative RV indexed EDV, ESV and EF were 47.4 (4.5) ml/m2, 22.6 (2.9) ml/m2 and 52.5 (3.3)% respectively. Mean LV and RV indexed mass were 26.4 (2.8) g/m2 and 12.5 (2.0) g/m2, respectively. There was no difference in ventricular volumes by gender. IOV was excellent with an intra-class coefficient > 0.95 except for RV mass (0.94).ConclusionThis study provides normative data on LV and RV parameters in healthy newborns, providing a novel resource for comparison with newborns with structural and functional heart disease.
Journal Article
Changes in left ventricular size, geometry, pump function and left heart pressures during healthy aging
2021
There are cross-sectional and longitudinal imaging studies using echocardiography and cardiac magnetic resonance in healthy adult subjects which have demonstrated associations of left ventricular (LV) structure and pump function with age. There are also cross-sectional data regarding the relationships of age with invasively measured left heart chamber pressures. Increasing age is associated with decreases in LV end-diastolic volume (LVEDV), end-systolic volume (LVESV), end-diastolic length (LVEDL), stroke volume (SV) and cardiac output (CO), and increases in relative wall thickness (RWT), LV mass/LVEDV ratio (LVMVR) and ejection fraction (LVEF). Older age is not accompanied by a change in mean left atrial (LA) pressure, but there is both direct and indirect evidence which suggests that LV end-diastolic pressure (LVEDP) increases with age. LVEDV remains lower in older than younger subjects during fluid infusion and the resulting increases in LA pressure. The combination of an increase in LVEF with reductions of both SV and CO demonstrates an age-related increase in divergence between LVEF and LV pump function. A lower LVEDV in older compared to younger subjects can be characterized as an aging-related decrease in LV capacity, with the higher LVEDP in older subjects also indicating a reduction of preload reserve.
Journal Article
Inter-study reproducibility of cardiovascular magnetic resonance myocardial feature tracking
2012
Cardiovascular magnetic resonance myocardial feature tracking (CMR-FT) is a recently described method of post processing routine cine acquisitions which aims to provide quantitative measurements of circumferentially and radially directed ventricular wall strain. Inter-study reproducibility is important for serial assessments however has not been defined for CMR-FT.
16 healthy volunteers were imaged 3 times within a single day. The first examination was performed at 0900 after fasting and was immediately followed by the second. The third, non-fasting scan, was performed at 1400.
CMR-FT measures of segmental and global strain parameters were calculated. Left ventricular (LV) circumferential and radial strain were determined in the short axis orientation (EccSAX and ErrSAX respectively). LV and right ventricular longitudinal strain and LV radial strain were determined from the 4-chamber orientation (EllLV, EllRV, and ErrLAX respectively). LV volumes and function were also analysed.
Inter-study reproducibility and study sample sizes required to demonstrate 5% changes in absolute strain were determined by comparison of the first and second exams. The third exam was used to determine whether diurnal variation affected reproducibility.
CMR-FT strain analysis inter-study reproducibility was variable. Global strain assessment was more reproducible than segmental analysis. Overall EccSAX was the most reproducible measure of strain: coefficient of variation (CV) 38% and 20.3% and intraclass correlation coefficient (ICC) 0.68 (0.55-0.78) and 0.7 (0.32-0.89) for segmental and global analysis respectively. The least reproducible segmental measure was EllRV: CV 60% and ICC 0.56 (0.41-0.69) whilst the least reproducible global measure was ErrLAX: CV 33.3% and ICC 0.44 (0–0.77). Variable reproducibility was also reflected in the calculated sample sizes, which ranged from 11 (global EccSAX) to 156 subjects (segmental EllRV). The reproducibility of LV volumes and function was excellent. There was no diurnal variation in global strain or LV volumetric measurements.
Inter-study reproducibility of CMR-FT varied between different parameters, as summarized above and was better for global rather than segmental analysis. It was not measurably affected by diurnal variation. CMR-FT may have potential for quantitative wall motion analysis with applications in patient management and clinical trials. However, inter-study reproducibility was relatively poor for segmental and long axis analyses of strain, which have yet to be validated, and may benefit from further development.
Journal Article