Left Ventricular Stroke Volume Research Articles

Oscillations of Hemodynamic Parameters Induced by Negative Pressure Breathing in Healthy Humans.

INTRODUCTION: Negative pressure breathing is breathing with decreased pressure in the respiratory tract without lowering pressure acting on the torso. We lowered air pressure only during inspiration (NPBin). NPBin, used to increase venous return to the heart, is considered a countermeasure against redistribution of body fluids toward the head during spaceflight. We studied NPBin effects on circulation in healthy humans with an emphasis on NPBin-induced oscillations of hemodynamic parameters synchronous with breathing. We propose an approach to analyze the oscillations based on coherent averaging.METHODS: Eight men ages 24-42 yr participated in the NPBin and control series. During the series, to reproduce fluids shift observed under microgravity, subjects were supine and head down (-8°). Duration of NPBin was 20 min, rarefaction -20 cm H₂O. Hemodynamic parameters were measured by Finometer. Electrical impedance measurements were used to estimate changes in blood filling of cerebral vessels.RESULTS: Mean values of hemodynamic parameters virtually did not change under NPBin, but NPBin induced oscillations of the parameters synchronous with respiration. Peak-to-peak amplitude under NPBin were: mean arterial pressure, 4 ± 1 (mmHg); stroke volume, 7 ± 3 (mL); and heart rate, 4 ± 1 (bpm). Electrical impedance of the head increased during inspiration. The increase under NPBin was three times greater than under normal breathing.DISCUSSION: Analysis of oscillations gives more information than analysis of mean values. NPBin induces short-term decrease in left ventricle stroke volume and arterial blood pressure during each inspiration; the decrease is compensated by increase after inspiration. NPBin facilitates redistribution of body fluids away from the head.Semenov YS, Melnikov IS, Luzhnov PV, Dyachenko AI. Oscillations of hemodynamic parameters induced by negative pressure breathing in healthy humans. Aerosp Med Hum Perform. 2024; 95(6):297-304.

Sex Differences in Aging-related Myocardial Stiffening Quantitatively Measured with MR Elastography.

Purpose To investigate the feasibility of using quantitative MR elastography (MRE) to characterize the influence of aging and sex on left ventricular (LV) shear stiffness. Materials and Methods In this prospective study, LV myocardial shear stiffness was measured in 109 healthy volunteers (age range: 18-84 years; mean age, 40 years ± 18 [SD]; 57 women, 52 men) enrolled between November 2018 and September 2019, using a 5-minute MRE acquisition added to a clinical MRI protocol. Linear regression models were used to estimate the association of cardiac MRI and MRE characteristics with age and sex; models were also fit to assess potential age-sex interaction. Results Myocardial shear stiffness significantly increased with age in female (age slope = 0.03 kPa/year ± 0.01, P = .009) but not male (age slope = 0.008 kPa/year ± 0.009, P = .38) volunteers. LV ejection fraction (LVEF) increased significantly with age in female volunteers (0.23% ± 0.08 per year, P = .005). LV end-systolic volume (LVESV) decreased with age in female volunteers (-0.20 mL/m2 ± 0.07, P = .003). MRI parameters, including T1, strain, and LV mass, did not demonstrate this interaction (P > .05). Myocardial shear stiffness was not significantly correlated with LVEF, LV stroke volume, body mass index, or any MRI strain metrics (P > .05) but showed significant correlations with LV end-diastolic volume/body surface area (BSA) (slope = -3 kPa/mL/m2 ± 1, P = .004, r2 = 0.08) and LVESV/BSA (-1.6 kPa/mL/m2 ± 0.5, P = .003, r2 = 0.08). Conclusion This study demonstrates that female, but not male, individuals experience disproportionate LV stiffening with natural aging, and these changes can be noninvasively measured with MRE. Keywords: Cardiac, Elastography, Biological Effects, Experimental Investigations, Sexual Dimorphisms, MR Elastography, Myocardial Shear Stiffness, Quantitative Stiffness Imaging, Aging Heart, Myocardial Biomechanics, Cardiac MRE Supplemental material is available for this article. Published under a CC BY 4.0 license.

Myocardial perfusion improvement and mechanism after percutaneous intramyocardial septal radiofrequency ablation in obstructive hypertrophic cardiomyopathy: a study of myocardial contrast echocardiography.

The data on myocardial perfusion of the percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) for obstructive hypertrophic cardiomyopathy (HOCM) are still lacking, although PIMSRA have been proved to be of great safety and efficacy. The aim of this study was to quantitatively analyze the changes in myocardial perfusion after PIMSRA using myocardial contrast echocardiography (MCE). 27 HOCM patients treated with PIMSRA were retrospectively analyzed, and their echocardiographic parameters and perfusion parameters of MCE were collected before and 12 months after PIMSRA. A reperfusion curve was used to quantify microvascular blood volume (A), microvascular flux rate (β), and microvascular blood flow (MBF) of each segment. Then the value difference (Δ) of parameters between post- and pre-operation were calculated. Finally, the correlation between the changes in MBF and in each echocardiographic parameter was analyzed. (1) Compared with baseline, the global A, β and MBF were significantly increased in HOCM patients after PIMSRA (all P < 0.001). The β, MBF were increased in the interventricular septum (P < 0.001, respectively), and the A, β, MBF were increased in the left ventricular wall (all P < 0.001). (2) Correlation analysis showed that the ΔMBF of interventricular septum was mainly negatively correlated with the maximum interventricular septum thickness (ΔIVSTmax, r=-0.670, P < 0.001), mean interventricular septum thickness (ΔIVSTmean, r=-0.690, P < 0.001), and left ventricular mass index (ΔLVMI, r=-0.774, P < 0.001), while the ΔMBF of left ventricular wall was positively correlated with left ventricular end-diastolic volume index (ΔLVEDVI, r = 0.621, P = 0.001) and stroke volume index (ΔSVI, r = 0.810, P < 0.001). Myocardial perfusion was improved at both interventricular septum and ventricular wall in HOCM patients after PIMSRA. MCE can provide a new dimension for the efficacy evaluation to PIMSRA procedure.

Acute effect of ultramarathon on systolic and diastolic cardiac function: Systematic review and meta-analysis

BackgroundUltramarathon running poses physiological challenges, impacting cardiac function. This systematic review and meta-analysis explore the acute effects of single-stage ultramarathon running on cardiac function. MethodsPreferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations were followed. Searches covered Medline, Embase, CINAHL, SPORTDiscus, Web of Science, Central Cochrane, and Scopus. Random effects meta-analyses assessed left ventricular (LV) and right ventricular (RV) variables, expressed as mean differences (MD) with 95% confidence intervals (CI). ResultsAmong 6972 studies, 17 were included. Post-ultramarathon reductions were found in LV end-diastolic diameter (LVEDD) (−1.24; 95% CI = −1.77, −0.71 mm), LV end-diastolic volume (LVEDV) (−9.92; 95% CI = −15.25, −4.60 ml), LV stroke volume (LVSV) (−8.96 ml, 95% CI -13.20, −4.72 ml), LV ejection fraction (LVEF) (−3.71; 95% CI = −5.21, −2.22%), LV global longitudinal strain (LVGLS) (−1.48; 95% CI = −2.21, −0.76%), E/A (−0.30; 95% CI = −0.38, −0.22 cm/s), .E' (−1.35 cm/s, 95% CI -1.91, −0.79 cm/s), RV fractional area change (RVFAC) (−3.34, 95% CI = −5.84, −0.84%), tricuspid annular plane systolic excursion (TAPSE) (−0.12, 95% CI = −0.22, −0.02 cm), RV global longitudinal strain (RVGLS) (−1.73, 95% CI = −2.87, −0.59%), with increases in RV end-diastolic area (RVEDA) (1.89, 95% CI = 0.63, 3.14 cm2), RV Peak A' (1.32 cm/s, 95% CI 0.20, 2.44), and heart rate (18.24, 95% CI = 15.16, 21.32). No significant differences were observed in LV end-systolic diameter (LVESD), LV end-systolic volume (LVESV), RV end-diastolic diameter (RVEDD), RV Peak E', and RV Peak S′. ConclusionsEvidence suggests immediate impairment of systolic and diastolic cardiac function post-ultramarathon running.

Accuracy of Shunt Volume Measured by Three-Dimensional Echocardiography and Cardiac Magnetic Resonance in Patients with an Atrial Septal Defect and a Dilated Right Ventricle

BackgroundThe accuracy of right ventricular (RV) quantification by three-dimensional echocardiography (3DE) has been reported mainly in patients with a normal RV. However, there are no data regarding the accuracy of 3DE in patients with a dilated RV, as in shunt diseases. In this study, we evaluated the accuracy of 3DE and that of volumetric cardiac magnetic resonance (CMR) for assessment of RV and left ventricular (LV) stroke volume (SV) and the pulmonary (Qp)/systemic (Qs) blood flow ratio in patients with an atrial septal defect (ASD) using the two-dimensional phase contrast (2DPC) method as the gold standard. MethodsWe retrospectively investigated 83 patients with ASD who underwent transcatheter closure and clinically indicated CMR and 3DE examinations. Qp/Qs was calculated using RV and LV SV measured by full-volume volumetric 3DE (Vol-3DE) and CMR (Vol-CMR) and by two-dimensional pulse Doppler quantification (2D-Dop); the parameters were compared using 2DPC-CMR as the gold standard. ResultsThere was no significant difference in the Qp/Qs value between 2DPC-CMR and Vol-3DE (2.29 ± 0.70 vs. 2.21 ± 0.63, P=0.79) and 2D-Dop (vs. 2.21 ± 0.65, P=1.00); however, a significant difference was found between 2DPC-CMR and Vol-CMR (P<0.001). The Qp/Qs value obtained using Vol-3DE showed the best correlation with 2DPC-CMR (r=0.93, P<0.001). The RV and LV SV values obtained by Vol-3DE showed the best correlation with 2DPC-CMR (RV SV, r=0.82, P<0.001; LV SV, r=0.73, P<0.001), although the absolute values were underestimated. ConclusionQp/Qs was more accurately evaluated by Vol-3DE than by Vol-CMR or 2D-Dop. 3DE assessment was feasible and reproducible even in a dilated RV.

Sex Differences in Left Ventricular Stroke Volume During Muscle Metaboreflex Activation

Introduction: Muscle metaboreflex activation (MMA) increases blood pressure, possibly by disproportionate increases in left ventricular (LV) stroke volume (SV) in males compared to females due to greater grip strength and metabolite production. The purpose of this study was to determine the effect of sex on SV during isolated MMA using cardiac MRI in young healthy adults. We hypothesized that SV would increase during MMA to a greater degree in males compared to females, and that this effect would be negated by accounting for grip strength. Methods: Ten males [23(2) yrs] and 10 females [26(5) yrs] underwent cardiac MRI during rest, 30% maximal voluntary contraction (MVC) isometric handgrip exercise (6 min), and isolation of MMA with brachial cuff circulatory occlusion (6 min). SV, end-systolic (ESV) and end-diastolic volumes (EDV) were measured by 2- and 4-chamber cine images and indexed (i) to body surface area to account for body size. Heart rate (HR, ECG) and mean arterial pressure (MAP, brachial cuff) were recorded. Cardiac output index (COi) and total peripheral resistance (TPR) were calculated. Analyses included ANOVA (sex × condition), ANCOVA [100% MVC (M=49(13) kg, F=26(7) kg) covariate], and linear regression. Results: SVi decreased from rest to MMA in males [67(8) to 61(5) mL/m2, p=0.0001] but not females [59(9) to 59(7) mL/m2, p=0.998; interaction p=0.002]. Notably, the reduction in SVi during MMA in males ( p=0.002) but not females ( p=0.957) remained with ANCOVA using MVC as the covariate (interaction p=0.021). ESVi increased during MMA in males [39(5) to 48(10) mL/m2, p&lt;0.0001] but not females [32(5) to 36(6) mL/m2, p=0.092; interaction p=0.029]. MMA decreased both EDVi ( p=0.004) and COi ( p=0.045) and increased both MAP ( p&lt;0.0001) and TPR ( p&lt;0.0001) pooled across sex. HR did not change with MMA in either sex (all p≥0.093). Linear regression revealed significant relationships between ΔSVi and ΔESVi in males ( p=0.002, R2=0.709) but not females ( p=0.223, R2=0.179) and between ΔSVi and ΔTPR in males ( p=0.005, R2=0.649) but not females ( p=0.522, R2=0.053). Conclusions: MMA lowers SVi in males but not females, even when accounting for grip strength and despite similar pressor responses in both groups. These findings from gold-standard MRI suggest differential LV responses to MMA between sexes, potentially related to greater sensitivity to increased TPR in males than females. Thus, sex differences in blood pressure control during MMA may be impacted by differences in LV afterload sensitivity. Further, the blood pressure response to MMA may be primarily mediated through TPR and not CO in healthy young adults. Heart and Stroke Foundation of Canada. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

The Cardiac and Cerebrovascular Response to Lower Body Negative Pressure in Patients with Postural Orthostatic Tachycardia Syndrome

Introduction: Postural orthostatic tachycardia syndrome (POTS) is characterized by excessive heart rate response upon standing and symptoms that drastically reduce quality of life. Symptoms are often cerebral in nature (e.g., dizziness, headache), however the relationship between the underlying physiology and the symptoms is unknown. We tested the hypothesis that, compared to healthy controls (HC) individuals with POTS would have greater decreases in cardiac, and cerebral hemodynamic function during a simulated orthostatic challenge (lower-body negative pressure; LBNP) measured using magnetic resonance (MR) imaging. Methods: Eleven patients with POTS (17±1yrs; 1 male) and 10 HC (18±2yrs; 1 male) were studied at rest (supine in MRI) and during 20-minutes of -25mmHg LBNP. Symptoms were measured by Vanderbilt Orthostatic Symptom Score (VOSS). Heart rate and blood pressure (BP) were measured using an automated cuff and finger pulse oximeter, respectively. Left and right ventricular volumes, ejection fraction, stroke volume (SV), and cardiac output (Qc) were determined by cardiac MR. Cerebral oxygen utilization (VO2) was calculated as cerebral blood flow (CBF) multiplied by venous oxygen saturation (SVO2), measured by MR phase contrast and susceptomtery-based oximetry in the superior sagittal sinus. Results: At rest, there were no differences between groups for any cardiac hemodynamic measure (p&gt;0.05 for all), however cerebral SvO2 and VO2 were lower in the POTS group (p=0.02 for both). In response to LBNP, patients with POTS had greater VOSS (25±21 vs 5±12; p=0.02). Heart rate increased in response to LBNP (p&lt;0.001), but the increase was not different between groups (HC: +9±8bpm; POTS: +13±11bpm; p=0.35). SV and Qc decreased during LBNP (both, p&lt;0.01), despite no change in mean arterial BP (p=0.13) which did not differ between groups (HC: +9±8mmHg; POTS: 3±6mmHg; p=0.377). Additionally, both left and right ventricular volumes as well as ejection fraction decreased during LBNP (p&lt;0.01 for all). The decreased Qc during LBNP coincided with lower CBF in the superior sagittal sinus (p=0.01) although the response was not different between groups (HC: -17±13ml/min; POTS: -25±32ml/min; p=0.51). Cerebral SvO2 also decreased during LBNP (p=0.03) indicating increased oxygen extraction, resulting in no change in cerebral VO2 during LBNP (p=0.28) and no difference between groups in the VO2 response (HC: -0.2±3.7ml/min; POTS: +1.1±2.0ml/min; p=0.33). Conclusion: In response to a simulated orthostatic challenge (-25mmHg LBNP), patients with POTS do not have impaired cardiac function or cerebral oxygenation despite having a higher symptom score; however, a stronger stimulus may have been necessary to expose differences. Further investigations are needed to elucidate mechanisms of autonomic dysfunction in this population. Women and Children's Health Research Institute. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Postoperative cognitive dysfunction in heart transplantation recipients.

This study aimed to investigate the occurrence and risk factors of postoperative neurocognitive disorder (NCD) in patients who underwent heart transplantation. Seventy-six heart transplant patients were analyzed for clinical data including gender, age, height, weight, education level, left ventricular ejection fraction (LVEF), stroke volume (SV), transplantation duration, and pretransplant medical history. Cognitive function was assessed using the mini-mental status examination (MMSE) and Montreal cognitive assessment (MoCA) scales. Patients were categorized into cognitively normal and impaired groups based on the presence or absence of cognitive dysfunction, and their cognitive function scores were compared. Multivariate logistic regression was used to identify independent risk factors for cognitive impairment in postoperative cardiac transplant patients. Cognitive dysfunction was observed in 48 out of 76 heart transplant patients, representing an incidence of 63.2%. Cognitive impairment in heart transplant recipients predominantly affected multiple cognitive domains. Logistic regression analysis identified age (OR=1.057, 95% CI 1.002-1.115), gender (OR=.200, 95% CI.044-.919), education level (OR=.728, 95% CI.600-.883), LVEF (OR=.891, 95% CI.820-.969), and history of diabetes (OR=7.674, 95% CI 1.317-44.733) as independent risk factors for postoperative NCD in heart transplant recipients (P<.05). The study found a high incidence of postoperative NCD in heart transplant patients, with gender, age, education level, LVEF, and diabetes history being significant risk factors. Early identification and intervention targeting these risk factors may help prevent NCD in postheart transplant patients and improve long-term outcomes.

Left atrial and left ventricular strain in feature-tracking cardiac magnetic resonance for predicting patients at high risk of sudden cardiac death in hypertrophic cardiomyopathy.

Sudden cardiac death (SCD) represents the most severe complication of hypertrophic cardiomyopathy (HCM). The risk stratification of SCD in patients with HCM remains a subject of ongoing debate, and the utility of left atrial (LA) and left ventricular (LV) myocardial strain for risk stratification of also SCD remains uncertain. Through use of feature-tracking cardiac magnetic resonance (FT-CMR), this study aimed to investigate the attenuation of LA and LV strain in HCM and to assess their predictive value in SCD. This retrospective and cross-sectional study included patients with HCM who underwent 3.0 T cardiac magnetic resonance (CMR) at a single institution. Feature-tracking strain analysis was conducted to obtain the strain rate (SR) and LV strain and to evaluate LV function. LA strain was measured during different functional phases including left atrial reservoir strain (LARS), LA conduit strain (LACS), and LA booster strain. All patients were categorized into high- and low-risk groups for SCD as defined by the 2020 American Heart Association/American College HCM implantable cardioverter defibrillator class of recommendation algorithm. Comparison between the two groups was conducted using the independent samples t test and the nonparametric rank sum test. Multivariate logistic regression analysis was performed to further identify the factors influencing SCD risk in HCM. Compared with those in the low-risk group, patients in the high-risk group had lower left ventricular ejection fraction (LVEF), LV stroke volume index (LVSVI), and LA stroke volume index (LASVI) but a higher LV end-systolic volume index (LVESVI), LV maximum wall thickness, and late gadolinium enhancement (LGE) (P<0.001). LV strain, SR, and LA strain all showed significant differences between the high- and low-risk groups (LARS: P=0.04; LACS: P=0.02; all other P values <0.001). The LV global circumferential strain (LVGCS) had a strong negative correlation with LVEF in patients with HCM (r=-0.76; P<0.001). Multivariate analysis showed that LV global radial strain (LVGRS) and LARS could be used for categorizing the patients into the high-risk group [LVGRS: odds ratio (OR) =0.69; 95% confidence interval (CI): 0.55-0.87, P<0.001; LARS: OR =1.39; 95% CI: 1.02-1.90, P=0.03]. The combined LVGRS-LARS model exhibited a superior diagnostic value for high risk of SCD [area under the curve (AUC) =0.95; 95% CI: 0.90-1.00; P<0.001] compared to LARS alone (AUC =0.63; 95% CI: 0.51-0.76; P=0.04). LA and LV strain measured by FT-CMR can accurately identify those patients with HCM at a high risk of SCD. This approach may prove considerably value in guiding early therapeutic intervention with implantable cardioverter-defibrillators (ICDs) to prevent adverse clinical outcomes.

AV-optimized conduction system pacing for treatment of AV dromotropathy: A randomized, cross-over study.

Severe first-degree atrioventricular (AV) block may produce symptoms similar to heart failure due to AV dyssynchrony, a syndrome termed AV dromotropathy. According to guidelines, it should be considered for permanent pacemaker implantation, yet evidence supporting this treatment is scarce. This study aimed to determine the impact of AV-optimized conduction system pacing (CSP) in patients with symptomatic severe first-degree AV block and echocardiographic signs of AV dyssynchrony. Patients with symptomatic first-degree AV block (PR > 250 ms), preserved left ventricular ejection fraction, narrow QRS, and AV dyssynchrony were included in the study. In a single-blind cross-over design, patients were randomized to AV sequential CSP or backup VVI pacing with a base rate of 40 bpm. We compared exercise capacity, echocardiographic parameters, and symptom occurrence at the end of 3 months of each period. Fourteen patients completed the study. During the AV-optimized CSP compared to the backup pacing period, patients achieved a higher workload on exercise test (147.2 ± 50.9 vs. 140.7 ± 55.8 W; p = .032), with a trend towards higher peak VO2 (23.3 ± 7.1 vs. 22.8 ± 7.1 mL/min/kg; p = .224), and higher left ventricular stroke volume (LVSV 74.5 ± 13.8 vs. 66.4 ± 12.5 mL; p < .001). Symptomatic improvement was recorded, with fewer patients reporting general tiredness and 71% of patients preferring the AV-optimized CSP (p = .008). AV-optimized CSP could improve symptoms, exercise capacity and LVSV in patients with severe first-degree AV block.

Left ventricular strain changes at high altitude in rats: a cardiac magnetic resonance tissue tracking imaging study

BackgroundLong-term exposure to a high altitude environment with low pressure and low oxygen could cause abnormalities in the structure and function of the heart. Myocardial strain is a sensitive indicator for assessing myocardial dysfunction, monitoring myocardial strain is of great significance for the early diagnosis and treatment of high altitude heart-related diseases. This study applies cardiac magnetic resonance tissue tracking technology (CMR-TT) to evaluate the changes in left ventricular myocardial function and structure in rats in high altitude environment.Methods6-week-old male rats were randomized into plateau hypoxia rats (plateau group, n = 21) as the experimental group and plain rats (plain group, n = 10) as the control group. plateau group rats were transported from Chengdu (altitude: 360 m), a city in a plateau located in southwestern China, to the Qinghai-Tibet Plateau (altitude: 3850 m), Yushu, China, and then fed for 12 weeks there, while plain group rats were fed in Chengdu(altitude: 360 m), China. Using 7.0 T cardiac magnetic resonance (CMR) to evaluate the left ventricular ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV) and stroke volume (SV), as well as myocardial strain parameters including the peak global longitudinal (GLS), radial (GRS), and circumferential strain (GCS). The rats were euthanized and a myocardial biopsy was obtained after the magnetic resonance imaging scan.ResultsThe plateau rats showed more lower left ventricular GLS and GRS (P < 0.05) than the plain rats. However, there was no statistically significant difference in left ventricular EDV, ESV, SV, EF and GCS compared to the plain rats (P > 0.05).ConclusionsAfter 12 weeks of exposure to high altitude low-pressure hypoxia environment, the left ventricular global strain was partially decreased and myocardium is damaged, while the whole heart ejection fraction was still preserved, the myocardial strain was more sensitive than the ejection fraction in monitoring cardiac function.

Glucose control during pregnancy in patients with type 1 diabetes correlates with fetal hemodynamics: a prospective longitudinal study

BackgroundMaternal diabetes adversely affects fetal cardiovascular system development. Previous studies have reported that the fetuses of mothers with diabetes exhibit both structural and functional changes; nevertheless, prior studies have not examined the association between glucose control and fetal cardiac morphology and performance. Thus, the objective was to determine the association between fetal cardiac morphology and function and maternal glucose control in type 1 diabetes and to compare the differences in measured cardiac parameters between the fetuses of mothers with diabetes and healthy controls.MethodsIn this prospective, longitudinal case-control study — including 62 pregnant women with type 1 diabetes mellitus and 30 healthy pregnant women — fetal cardiac assessment using B-mode, M-mode, and spectral pulsed-wave Doppler was performed in the second and third trimesters. In women with T1DM, glycated hemoglobin and data obtained from glucose sensors — including the percentage of time in, below, and above the range (TIR, TBR, and TAR, respectively), and coefficient of variation (CV) — were analyzed across three time periods: the last menstrual period to 13 (V1), 14–22 (V2), and 23–32 weeks (V3) of gestation. Fetal cardiac indices were compared between groups, and the correlation between glucose control and fetal cardiac indices was assessed.ResultsAt 28–32 weeks, the fetuses of women with T1DM exhibited increased left ventricular end-diastolic length, relative interventricular septum thickness, right ventricular cardiac output, and pulmonary valve peak systolic velocity compared with healthy controls. At 18–22 weeks, pulmonary and aortic valve diameters, left and right ventricular stroke volumes, and left cardiac output inversely correlated with the CV and glycated hemoglobin levels at V1 and V2. Furthermore, at 28–32 weeks, pulmonary and aortic valve diameters, left ventricular stroke volume, cardiac output, and right/left atrioventricular valve ratio inversely correlated with the TBR at V1, V2, and V3. Moreover, diastolic functional parameters correlated with the TAR and glycated hemoglobin levels, particularly after the first trimester.ConclusionIn women with T1DM, maternal hyperglycemia during pregnancy correlates with fetal diastolic function, whereas glucose variability and hypoglycemia inversely correlate with fetal left ventricular systolic function in the second and third trimesters.

Comparison of Left Ventricular Stroke Volume in 2nd- and 3rd Trimester Fetuses Measured by the Product of VTI and Aortic Annular Area With That Assessed by Simpson's Single-Plane Rule Using the STE Technique.

The aim of the study was to compare left ventricle stroke volume in healthy, eutrophic fetuses in the 2nd and 3rd trimesters evaluated using the velocity time integral and aortic annulus area with left ventricular stroke volume measured using Simpson's single-plane rule and to determine the discrepancy equation. The study included 354 fetuses. In each fetus, during the same examination, simultaneous assessment of stroke volume was performed by pulsed-wave Doppler using the product of the velocity time integral and aortic annulus area and by the fetalHQ® software using Simpson's single-plane rule. The Mann-Whitney U test was used to compare the "product-derived" stroke volume and stroke volume using fetalHQ® software values in the 2nd and 3rd trimesters separately. The agreement between the two methods were verified using Bland-Altman analysis. A linear regression model was used to obtain the discrepancy equation. In the 2nd trimester, the mean percentage difference between both the techniques showed that the stroke volume values determined using pulsed-wave Doppler were, on average, 88% higher than the stroke volume values determined using fetalHQ®. The upper limit of agreement between the compared techniques was approximately 146% and the lower limit of agreement was equal to 29.6%. In the 3rd trimester, the results indicated that the stroke volume values determined using pulsed-wave Doppler were, on average, 76% higher than the stroke volume values determined using fetalHQ®. The upper limit of agreement between the compared techniques was approximately 129% and the lower limit of agreement was 23%. Based on the results of the linear regression models, discrepancy formulas of the stroke volume values were obtained. The equations to calculate the predicted mean and standard deviations were used to compute the reference intervals for the mean, 5th and 95th centiles. The calculation of left ventricular stroke volume using pulsed Doppler has higher result in relation to stroke volume determined using Simpson's rule significantly. The aortic annulus area showed a higher correlation regarding stroke volume than the velocity time integral in both the 2nd and 3rd trimesters. Stroke volume increased with the increase in aortic annulus area, whereas the velocity time integral remained relatively constant. The retrospective analysis of the collected material enabled the determination of the discrepancy equation.

Trajectories of functional and structural myocardial parameters in post-COVID-19 syndrome-insights from mid-term follow-up by cardiovascular magnetic resonance.

Myocardial tissue alterations in patients with post-Coronavirus disease 2019 syndrome (PCS) are often subtle and mild. Reports vary in the prevalence of non-ischemic and ischemic injuries as well as the extent of ongoing myocardial inflammation. The exact relevance of these myocardial alterations is not fully understood. This study aimed at describing the trajectories of myocardial alterations in PCS patients by mid-term follow-up with cardiovascular magnetic resonance (CMR). This study entails a retrospective analysis of symptomatic PCS patients referred for follow-up CMR between August 2020 and May 2023 due to mildly affected or reduced left or right ventricular function (LV and RV, respectively) and structural myocardial alterations, e.g., focal and diffuse fibrosis, on baseline scans. Follow-up CMR protocol consisted of cine images and full coverage native T1 and T2 mapping. Baseline and follow-up scans were compared using t-tests or Wilcoxon tests. Post-hoc analysis was carried out in a subgroup based on the change of LV stroke volume (SV) between scans. In total, 43 patients [median age (interquartile range) 46 (37-56) years, 33 women] received follow-ups 347 (167-651) days after initial diagnosis. A decrease in symptoms was recorded on follow-ups (p < 0.03) with 23 patients being asymptomatic at follow-ups [symptomatic at baseline 43/43 (100%) vs. symptomatic at follow-up 21/43 (49%), p < 0.001]. Functional improvement was noted for LV-SV [83.3 (72.7-95.0) vs. 84.0 (77.0-100.3) ml; p = 0.045], global radial [25.3% (23.4%-27.9%) vs. 27.4% (24.4%-33.1%); p < 0.001], and circumferential strains [-16.5% (-17.5% to -15.6%) vs. -17.2% (-19.5% to -16.1%); p < 0.001]. In total, 17 patients had an LV-SV change >10% on follow-up scans (5 with a decrease and 12 with an increase), with LV-SV, RV-SV, and global longitudinal strain being discriminatory variables on baseline scans (p = 0.01, 0.02, and 0.04, respectively). T1- or T2-analysis revealed no changes, remaining within normal limits. Symptomatic load as well as blood pressures decreased on follow-up. CMR did not detect significant changes in tissue parameters; however, volumetric, specifically LV-SV, and deformation indexes improved during mid-term follow-up.

Long-term efficacy and safety of elamipretide in patients with Barth syndrome: 168-week open-label extension results of TAZPOWER

PurposeEvaluate long-term efficacy and safety of elamipretide during the open-label extension (OLE) of the TAZPOWER trial in individuals with Barth syndrome (BTHS). MethodsTAZPOWER was a 28-week randomized, double-blind, and placebo-controlled trial followed by a 168-week OLE. Patients entering the OLE continued elamipretide 40 mg subcutaneous daily. OLE primary endpoints were safety and tolerability; secondary endpoints included change from baseline in the 6-minute walk test (6MWT) and BarTH Syndrome Symptom Assessment (BTHS-SA) Total Fatigue. Muscle strength, physician- and patient-assessed outcomes, echocardiographic parameters, and biomarkers, including cardiolipin (CL) and monolysocardiolipin (MLCL), were assessed. ResultsTen patients entered the OLE; 8 reached the week 168 visit. Elamipretide was well tolerated, with injection-site reactions being the most common adverse events. Significant improvements from OLE baseline on 6MWT occurred at all OLE time points (cumulative 96.1 m of improvement [week 168, P = .003]). Mean BTHS-SA Total Fatigue scores were below baseline (improved) at all OLE time points. Three-dimensional (3D) left ventricular stroke, end-diastolic, and end-systolic volumes improved, showing significant trends for improvement from baseline to week 168. MLCL/CL values showed improvement, correlating to important clinical outcomes. ConclusionElamipretide was associated with sustained long-term tolerability and efficacy, with improvements in functional assessments and cardiac function in BTHS.

Multiparametric Cardiac Magnetic Resonance Assessment in Sickle Beta Thalassemia.

Cardiac involvement in sickle beta thalassemia (Sβ-thal) patients has been poorly investigated. We aimed to evaluate cardiac function and myocardial iron overload by cardiovascular magnetic resonance (CMR) in patients with Sβ-thal. One-hundred and eleven Sβ-thal patients consecutively enrolled in the Myocardial Iron Overload in Thalassemia (MIOT) network were studied and compared with 46 sickle cell anemia (SCA) patients and with 111 gender- and age- matched healthy volunteers. Cine images were acquired to quantify biventricular function. Myocardial iron overload (MIO) was assessed by the T2* technique, while macroscopic myocardial fibrosis was evaluated by the late gadolinium enhancement (LGE) technique. In Sβ-thal and SCA patients, the morphological and functional CMR parameters were not significantly different, except for the left atrial area and left ventricular (LV) stroke volume, indexed by body surface area (p = 0.023 and p = 0.048, respectively), which were significantly higher in SCA patients. No significant differences between the two groups were found in terms of myocardial iron overload and macroscopic myocardial fibrosis. When compared to healthy subjects, Sβ-thal patients showed significantly higher bi-atrial and biventricular parameters, except for LV ejection fraction, which was significantly lower. The CMR analysis confirmed that Sβ-thal and SCA patients are phenotypically similar. Since Sβ-thal patients showed markedly different morphological and functional indices from healthy subjects, it would be useful to identify Sβ-thal/SCA-specific bi-atrial and biventricular reference values.

APOEε4 carriage associates with improved myocardial performance from adolescence to older age

BackgroundAlthough APOE ε4 allele carriage confers a risk for coronary artery disease, its persistence in humans might be explained by certain survival advantages (antagonistic pleiotropy).MethodsCombining data from ~ 37,000 persons from three older age British cohorts (1946 National Survey of Health and Development [NSHD], Southall and Brent Revised [SABRE], and UK Biobank) and one younger age cohort (Avon Longitudinal Study of Parents and Children [ALSPAC]), we explored whether APOE ε4 carriage associates with beneficial or unfavorable left ventricular (LV) structural and functional metrics by echocardiography and cardiovascular magnetic resonance (CMR).ResultsCompared to the non-APOE ε4 group, APOE ε4 carriers had similar cardiac phenotypes in terms of LV ejection fraction, E/e’, posterior wall and interventricular septal thickness, and LV mass. However, they had improved myocardial performance resulting in greater LV stroke volume generation per 1 mL of myocardium (higher myocardial contraction fraction). In NSHD (n = 1467) and SABRE (n = 1187), ε4 carriers had a 4% higher MCF (95% CI 1–7%, p = 0.016) using echocardiography. Using CMR data, in UK Biobank (n = 32,972), ε4 carriers had a 1% higher MCF 95% (CI 0–1%, p = 0.020) with a dose-response relationship based on the number of ε4 alleles. In addition, UK Biobank ε4 carriers also had more favorable radial and longitudinal strain rates compared to non APOE ε4 carriers. In ALSPAC (n = 1397), APOE ε4 carriers aged < 24 years had a 2% higher MCF (95% CI 0–5%, p = 0.059).ConclusionsBy triangulating results in four independent cohorts, across imaging modalities (echocardiography and CMR), and in ~ 37,000 individuals, our results point towards an association between ε4 carriage and improved cardiac performance in terms of LV MCF. This potentially favorable cardiac phenotype adds to the growing number of reported survival advantages attributed to the pleiotropic effects APOE ε4 carriage that might collectively explain its persistence in human populations.

Effect of furosemide combined with continuous renal replacement therapy on cardiorenal function and inflammatory response in patients with chronic renal and heart failure after hemodialysis

Purpose: To determine the effect of furosemide combined with continuous renal replacement therapy (CRRT) on cardiorenal function and inflammatory response in patients with chronic renal failure (CRF) and heart failure after hemodialysis. &#x0D; Methods: 130 patients with both CRF and heart failure, who underwent hemodialysis at the Second Hospital Affiliated to Hainan Medical College, China, from October 2020 to October 2022 were recruited as study subjects. They were randomly divided into two groups, with control group administered the Continuous Renal Replacement Therapy (CRRT) while study group received furosemide in addition. The study assessed the clinical outcomes, cardiorenal function and inflammatory factors before and after treatment. Additionally, adverse reactions during treatment were documented for both groups. &#x0D; Results: Study group exhibited a significantly higher (p &lt; 0.001) total response rate compared to control group. Post-treatment, both groups displayed significant increases (p &lt; 0.05) in left ventricular ejection fraction, cardiac output and stroke volume, with study group showing significantly superior results (p &lt; 0.05). Furthermore, post-treatment, both groups experienced significant reductions (p &lt; 0.05) in serum creatinine, blood urea nitrogen, and 24-hour urinary protein levels, with study group displaying significantly lower levels (p &lt; 0.05). Additionally, the interleukin-6, interleukin-1β and tumor necrosis factor-α levels decreased significantly in both groups post-treatment, with study group exhibiting significantly lower levels (p &lt; 0.05). There was no significant difference in adverse reaction incidence between the two groups. &#x0D; Conclusion: Furosemide combined with CRRT significantly improves cardiorenal function and reduces inflammatory response in patients with CRF and heart failure after hemodialysis. Future research could optimize dosage and administration protocols, explore long-term effects and assess applicability in diverse patient populations.

Implications of tricuspid regurgitation and right ventricular volume overload in patients with heart failure with preserved ejection fraction.

The aim of this study was to assess the pathophysiological implications of severe tricuspid regurgitation (TR) in patients with heart failure with preserved ejection fraction (HFpEF) by using tricuspid transcatheter edge-to-edge repair (T-TEER) as a model of right ventricular (RV) volume overload relief. This prospective interventional single arm trial (NCT04782908) included patients with invasively diagnosed HFpEF. The following parameters were prospectively assessed before and after T-TEER: left ventricular (LV) diastolic properties by invasive pressure-volume loop recordings; biventricular time-volume curves and function as well as septal curvature by cardiac magnetic resonance imaging; strain analyses for timing of septal motion. Overall, 20 patients (median age 78, interquartile range [IQR] 72-83 years, 65% female) were included. T-TEER reduced TR by a median of 2 (of 5) grades (IQR 2-1). T-TEER increased LV stroke volume and LV end-diastolic volume (LVEDV) (p < 0.001), without increasing LV end-diastolic pressure (LVEDP) (p = 0.094), consequently diastolic function improved with a reduction in LVEDP/LVEDV (p = 0.001) and a rightward shift of the end-diastolic pressure-volume relationship. The increase in LVEDV correlated with a decrease in RV end-diastolic volume (p < 0.001) and LV transmural pressure increased (p = 0.028). Secondary to a decrease in early RV filling, improvements in early LV filling were observed, correlating with an alleviation of leftwards bowing of the septum (p < 0.01, respectively). Diastolic LV properties in patients with HFpEF and severe TR are importantly determined by ventricular interaction in the setting of RV volume overload. T-TEER reduces RV volume overload and improves biventricular interaction and physiology.

Sex-specific structural and functional cardiac remodeling during healthy aging assessed by cardiovascular magnetic resonance.

Aging as a major non-modifiable cardiac risk factor challenges future cardiovascular medicine and economic demands, which requires further assessments addressing physiological age-associated cardiac changes. Using cardiovascular magnetic resonance (CMR), this study aims to characterize sex-specific ventricular adaptations during healthy aging. The population included healthy volunteers who underwent CMR at 1.5 or 3 Tesla scanners applying cine-imaging with a short-axis coverage of the left (LV) and right (RV) ventricle. The cohort was divided by sex (female and male) and age (subgroups in years): 1 (19-29), 2 (30-39), 3 (40-49), and 4 (≥50). Cardiac adaptations were quantitatively assessed by CMR indices. After the exclusion of missing or poor-quality CMR datasets or diagnosed disease, 140 of 203 volunteers were part of the final analysis. Women generally had smaller ventricular dimensions and LV mass, but higher biventricular systolic function. There was a significant age-associated decrease in ventricular dimensions as well as a significant increase in LV mass-to-volume ratio (LV-MVR, concentricity) in both sexes (LV-MVR in g/ml: age group 1 vs. 4: females 0.50 vs. 0.57, p=0.016, males 0.56 vs. 0.67, p=0.024). LV stroke volume index decreased significantly with age in both sexes, but stronger for men than for women (in ml/m2: agegroup 1 vs. 4: females 51.76 vs. 41.94, p<0.001, males 55.31 vs. 40.78, p<0.001). Ventricular proportions (RV-to-LV-volume ratio) were constant between the age groups in both sexes. In both sexes, healthy aging was associated with an increase in concentricity and a decline in ventricular dimensions. Furthermore, relevant age-related sex differences in systolic LV performance were observed.