Deceleration Time Research Articles

Evaluation of Right Ventricular Diastolic Function among HIV-1-Infected Patients on Highly Active Antiretroviral Therapy and its Relationship with CD4 Cell Count and Viral Load

Abstract Context: With the introduction of highly active antiretroviral therapy, human immunodeficiency virus (HIV) patients live longer and therefore develop complications such as cardiovascular diseases. The prevalence of left ventricular diastolic dysfunction among HIV-infected patients ranges from 2.7% to 64%. Data on right ventricular diastolic function among HIV-infected patients in our region of northeastern Nigeria are lacking. Aims: We therefore assessed right ventricular diastolic function among HIV-infected patients on highly active antiretroviral therapy (HAART). Materials and Methods: This cross-sectional study was conducted among HIV-infected patients receiving HAART at the Federal Medical Centre Nguru, Yobe State, Northeastern Nigeria. Tricuspid flow E/A ratio, right ventricular deceleration time, and tissue Doppler E/e’ waves were used to assess the right ventricular diastolic function. Results: One hundred and seven subjects were recruited into the study comprising 70 (65.4%) females and 37 (34.6%) males. The prevalence of right ventricular diastolic dysfunction is 12.15%. CD4 cell count correlated positively with right ventricular deceleration time and negatively with tricuspid E/A ratio. Viral load correlated positively with the tricuspid E/A ratio and negatively with the tricuspid E/e ratio and right ventricular deceleration time. Conclusion: Right ventricular diastolic dysfunction is not uncommon among HIV-infected patients in northeastern Nigeria; its prevalence was found to be 12.15%, and there was a significant positive correlation between right ventricular deceleration time and CD4 cell count and a significant negative correlation between right ventricular deceleration time and viral load, suggesting that lower CD4 cell count and higher viral load are associated with worsening right ventricular diastolic function.

Obesity and its impact on functional capacity: understanding the interplay for health management

Abstract Background Cardiopulmonary exercise testing (CPET) plays a significant role in evaluating obese individuals due to the unique physiological challenges they face during exercise. As diastolic function is impaired in majority of morbidly obese pts, combination of CPET with diastolic stress echocardiography may add more information to objective assessment Objective To assess the value of combined stress echo CPET (ESE-CPET) in assessment of diastolic function in morbidly obese pts. Methods We studied 400 pts (74% female, age 39.2±9.9 years) referred for bariatric surgery. Echocardiographic measurements have been performed before CPET and immediately after the test. CPET was performed on treadmill (maximal Bruce) with breath-by-breath gas analysis. We measured both peak oxygen consumption (peakVO2) and VO2 at anaerobic threshold (AT), as well as other ventilatory and hemodynamic parameters. Results Mean BMI was 44± kg/m2. Left ventricular ejection fraction was 63.5±5.6%. Mean VO2 at AT was 17±2 ml/kg/min, mean Peak VO2 was 19±4 ml/kg/min. Resting eho : mitral E to A wave (E/A),deceleration time ( Dt) and mitral E to mitral anular E’ (E/E’) values did not correlate significantly with parameters of CPET. However, there was significant correlation between maximal E/ E’ with PeakVO2 and VO2 at AT (p<0.001), , Pet CO2 (p=0.0001) as well as with myocardial performance index as a parameter of global left ventricular function (p<0.001) However, VE/VCO2 was the strongest predictor of increase in E/ E’≥ 15 indicating the importance of ventilatory parameters and dynamic tests. Conclusions Assessment of diastolic function in morbid obese patients represents a great challenge to cardiologists because obesity contributed significantly to deterioration of diastolic function. Combined stress echo CPET showed the advantage and benefit of integrated evaluation of both pulmonary and cardiovascular function representing as a significant step forward in assessment of diastolic function overcoming the limitations of resting echocardiography and CPET performed as a single test.

Estimated transmitral E- and A-wave overlapping predicted prognosis in patient with heart failure with preserved ejection

Abstract Background The impact of heart rate (HR) variability on clinical outcomes in patients with heart failure with preserved ejection fraction (HFpEF) is not fully understood. Variations in HR may affect transmitral blood flow and consequently left ventricular filling and left atrial pressure. Changes in HR can cause the transmitral E-wave and A-wave to merge at higher HRs, while their interval lengthens at slower HRs (Figure: left). A recent study (Izumida. ESC Heart Fail. 2020;7:3231) demonstrated that the degree of overlap or interval between E- and A-waves can be estimated using resting HR and the deceleration time of the E-wave (DcT) on Doppler echocardiography. Purpose This study aims to investigate the relationship between the estimated overlap length between E- and A-waves and prognosis in patients with HFpEF. Methods Echocardiography was performed before hospital discharge in 398 patients (80±9 years, 59.0% female) hospitalized for decompensated HFpEF who were registered in the PURSUIT-HFpEF (Prospective, Multicenter, Observational Study of Patients with Heart Failure with Preserved Ejection Fraction) registry. The overlap length between E- and A waves was estimated using the formula [6.2 × HR (bpm) + 0.81 × DcT (ms) -589 (ms)] as previously described (a negative value means distance between two waves). Patients were divided into four groups based on quartiles of overlap length (Q1 to Q4, with Q4 representing the highest overlap length) and followed for a median duration of 759 days (interquartile range: 370, 1107 days) to observe all-cause mortality. Results The estimated overlap length in the study patients was -167±85 ms, and 105 deaths occurred during follow-up. The overlap length was selected as an independent predictor for all-cause mortality by Cox proportional hazards regression analysis (p=0.04), whereas HR or DcT was not. Kaplan-Meier curves indicated the difference in all-cause mortality among 4 groups (Figure: Right, p=0.02 by log-rank test), and the Q4 group (335 to -123ms) showed significantly higher mortality than the Q2 (-124 to -173 ms, p=0.03). Conclusion The overlap length of E and A predicted mortality in HFpEF patients, and the presence of overlap or shorter interval were associated with higher mortality. Optimal HR based on overlap length may be a new target for HFpEF therapy.Figure 1

Associate variables of coronary computed tomographic angiography-derived extracellular volume fraction and cardiac magnetic resonance-derived late-gadolinium enhancement

Abstract Background Coronary computed tomographic angiography (CCTA) with late-iodine enhancement enables the segmental quantification of extracellular volume (ECV) fraction which represents myocardial fibrosis. However, its association with cardiac magnetic resonance (CMR)-derived late gadolinium enhancement (LGE) has not been fully elucidated. Purpose We aimed to assess the concordance and discordance between CCTA-derived ECV and CMR-derived LGE and to investigate associated variables of each index. Methods This retrospective analysis included a total of 123 segments from 41 patients (anterior, inferior and lateral segments per patient) with known or suspected coronary artery disease (CAD) who underwent both clinically indicated CCTA and CMR. Patients with cardiomyopathy such as amyloidosis were excluded. Myocardial fibrosis was evaluated by CCTA-derived segmental ECV and by CMR-LGE with ischemic pattern on a per-segment basis (AHA 16 segments). Clinical and echocardiographic variables associated with CCTA-derived segmental ECV and CMR-LGE were studied by univariable linear and logistic regression analyses, respectively. Results Among the 123 segments, 21 segments showed ischemic CMR-LGE pattern. CCTA-ECV was significantly higher in segments with versus without CMR-LGE (42 [39, 47] % versus 34 [29, 39] %, P<0.01). Receiver-operating characteristic curve analysis showed that the best cut-off of CCTA-ECV to predict CMR-LGE was 38.9% (area under the curve 0.82 [95% confidence interval 0.74, 0.90], positive predictive value: 40.0%, negative predictive value: 96.2%). Univariable analyses revealed that male sex, prior history of revascularization, usage of statin, aspirin, angiotensin-converting enzyme inhibitor and beta-blockade, higher C-reactive protein, NT-pro BNP, lower left ventricular ejection fraction, greater left ventricular chamber size, shorter deceleration time, and larger segmental and global longitudinal strain were associated with both higher CCTA-ECV and the presence of CMR-LGE. Lower lipid profiles, higher high-sense troponin I, and greater left atrial volume index were associated with higher CCTA-ECV, while not with the presence of CMR-LGE. The frequency of CMR-LGE were significantly different according to CCTA-ECV tertiles. (P<0.05) Statin use and higher NT-proBNP were determinants of the highest ECV tertile without LGE. Conclusion We found a strong interrelationship between variables associated with ECV and the presence of LGE, although high ECV may not necessarily indicate the presence of LGE in patients with known or suspected CAD. Clinical factors associated with discordance, such as high-ECV without CMR-LGE, should be taken into account in the assessment of ECV and LGE. Further studies are needed to elucidate clinical significance of the concordance and discordance between ECV and LGE.

Acute echocardiographic assessment of patients with ST-elevation myocardial infarction in detecting clinically hidden hemodynamic deterioration

Abstract Background Transthoracic echocardiography (TTE) offers an immediate non-invasive assessment of cardiac morphology and function that can be performed bedside. Acute TTE in the catheterization laboratory (cath.lab.) may be helpful to identify markers of subsequent development of cardiogenic shock (CS) in patients with ST-elevation myocardial infarction (STEMI) in addition to the previously validated ORBI risk score. This relationship has not been investigated thoroughly previously. Purpose To investigate the association between acute TTE estimates of left ventricular (LV) function prior to primary percutaneous coronary intervention (pPCI) in STEMI patients and pro-B-type natriuretic peptide (proBNP) as a proxy associated with of CS development. Method From September 2023 all non-CS STEMI patients at one tertiary heart center underwent acute bedside TTE in the cath.lab. and ORBI risk score assessing the risk of CS development aiming for inclusion of 500 patients. The 5 minutes TTE-protocol consisted of LV ejection fraction (EF), LV outflow tract velocity time integral (LVOT VTI), mitral inflow (E and E/A), mitral deceleration time, and mitral annular early diastolic velocity é lateral. The primary endpoint was proBNP measured 24 hours (h) after pPCI (12-36h) stratified in quartiles (Q4 vs. Q1-3). The correlation between proBNP and TTE measurements and proBNP and ORBI risk score was examined using univariate linear regression models. Results Until now 153 STEMI patients (mean age 64 years, 25% female) were studied. Anterior STEMI was present in 36%, and median time from cath. lab. arrival to first wire over the culprit lesion was 28 minutes (IQR 24; 37). Patients with high proBNP level (Q4 vs. Q1-3) had significantly higher heart rate (median 84 bpm vs. 72 bpm) and Killip Class>1 (16% vs. 0%) at admission, but similar lactate levels (1.8mM vs. 1.5mM), systolic blood pressure (130 mmHg vs. 137 mmHg), and out-of-hospital cardiac arrest (11% vs. 12%). Patients with high proBNP levels (Q4 vs. Q1-3) had significantly lower LVEF (35% vs. 50%), higher E/é lateral (median 11.4 vs. 7.9), and higher ORBI risk score (median 8 vs. 4). LVEF, LVOT VTI, E/é lateral, and ORBI risk score were significantly associated with proBNP (Figure 1). Two patients developed CS after the pPCI; one with high proBNP level Q4, and one deceased prior to proBNP measurement. Conclusion Acute TTE is an easy tool for assessment of the acute hemodynamic status in STEMI patients bedside in the cath.lab., and it can be without delaying time to revascularization. LVEF, LVOT VTI, E/é lateral, and ORBI were all parameters associated with increased levels of the hemodynamic biomarker proBNP, and may together with the ORBI risk score improve the assessment and risk stratification of STEMI-patients at risk of CS-development.Figure 1.

Latent class analysis reveals a novel phenotype of heart failure that spans the left ventricular ejection fraction range

Abstract Background It is increasingly evident that heart failure (HF) represents a heterogenous syndrome rather than a single clinical entity. The elusiveness of effective therapies for heart failure with preserved ejection fraction (HFpEF) has led to a consensus that our current, unidimensional construct of HF using only left ventricular ejection fraction (LVEF) does not adequately capture the multiplicity of the disease states. The ability to harmonize echocardiographic data from multiple sources has enabled use of unsupervised cluster-based analysis to identify multidimensional cardiac structural phenotypes. Purpose To identify cardiac structural phenotypes of HF across the LVEF spectrum. Methods We harmonized echocardiographic data from eight randomized clinical HF trials (ESCAPE, EXACT-HF, FIGHT, I-PRESERVE, NEAT-HFpEF, RELAX, STICH and TOPCAT), which included both HFrEF and HFpEF populations (total n=4223 echocardiograms). These studies collectively spanned the years 2000 through 2015 and represent a balanced LVEF distribution. Latent class analysis (LCA) was performed iteratively to identify predominant structural phenotypes using LVEF, RV function, LV end diastolic volume, LV mass index, eccentricity, mitral valve deceleration time, and lateral E/e’ ratio. Results LCA identified 4 echocardiographic phenotypes. Three phenotypes skewed toward either high or low EF, but one phenotype demonstrated a relatively even distribution of patients with HFrEF, heart failure with mildly reduced ejection fraction (HFmrEF) and HFpEF (36.0%, 21.4% and 42.7%, respectively). Patients in this phenotype had preserved RV function and left ventricular hypertrophy (97%), of which 56.8% had concentric and 43.2% eccentric LVH. E/e’ was normal in 63% of subjects. A vast majority (91%) of patients had recent-onset HF (diagnosed within the past year). There were no remarkable distinguishing comorbidities. Notable differences in biomarker profile included higher levels of troponin I, cyclic GMP and lower levels of neurohormones (aldosterone, endothelin-1, dopamine, and norepinephrine) than the other phenotypes. Conclusions This is the first cluster-based analysis to identify a quantitative structural HF phenotype of HF that is not distinguished by LVEF. While the underlying pathophysiology is unclear, most patients have recent onset HF and biomarker profiles with relatively low neurohormone activity. These features may reflect a distinct pathophysiology that could indicate a specific, targeted intervention.

Cardiac structural and functional changes in OSAHS patients with heart failure with preserved ejection fraction and atrial fibrillation

ObjectiveTo explore the cardiac structural and functional changes in obstructive sleep apnea-hypopnea syndrome (OSAHS) patients with heart failure with preserved ejection fraction (HFpEF) and atrial fibrillation (AF).MethodsThis retrospective study included 336 OSAHS patients with HFpEF. They were divided into Groups A (without an AF history and no AF episodes during cardiac color ultrasound examination), B (an AF history but no AF episodes), and C (an AF history and AF episodes). They all received cardiac color ultrasound examinations. Cardiac structural and functional changes in ultrasonic cardiograms were compared between the three groups.ResultsCompared with Groups A and B, Group C showed increased left atrial diameter (LAD), left atrial volume (LAV), right ventricular diameter at end-diastole (RV-D1), right ventricular diameter at end-systole (RV-D2), right ventricular outflow tract diameter (RVOT2), right atrial diameter at end-diastole (RA-D1), right atrial diameter at end-systole (RA-D2), and right atrial area (RAA) (p < 0.05). Compared with Group A, Group C showed decreased fractional shortening (FS), left ventricular ejection fraction (LVEF), deceleration time (DT), isovolumic relaxation time (IVRT), E/E’ ratio, and peak filling velocity (FPV), as well as increased E and E’ (p < 0.01). Compared with Group B, Group C showed decreased FS and increased E and FPV (p < 0.01).ConclusionIn OSAHS patients with HFpEF and AF, cardiac remodeling and AF incidence are increased with the severity of OSAHS. OSAHS patients with HFpEF combined with AF have a significantly higher abnormality rate in right heart structural indices rather than left heart, mainly in the right atrium.

Qualitative and quantitative analysis of solid renal tumors by high-frame-rate contrast-enhanced ultrasound

ObjectiveTo analyze the characteristics of high-frame-rate contrast-enhanced ultrasound (H-CEUS) in solid renal tumors using qualitative and quantitative methods.MethodsSeventy-five patients who underwent preoperative conventional ultrasound (US), conventional contrast-enhanced ultrasound (C-CEUS), and H-CEUS examination of renal tumors were retrospectively analyzed, with a total of 89 renal masses. The masses were divided into the benign (30 masses) and malignant groups (59 masses) based on the results of enhanced computer tomography and pathology. The location, diameter, shape, border, calcification, and color doppler blood flow imaging (CDFI) of the lesions were observed by US, and the characteristics of the C-CEUS and H-CEUS images were qualitatively and quantitatively analyzed. The χ² test or Fisher’s exact probability method was used to compare the US image characteristics between the benign and malignant groups, and the image characteristics of C-CEUS and H-CEUS between the benign and malignant groups. Moreover, the nonparametric Mann-Whitney test was used to compare the differences in C-CEUS and H-CEUS time-intensity curve (TIC) parameters.ResultsSignificant differences in gender, surgical approach, echogenicity, and CDFI were observed between the malignant and benign groups (p = 0.003, < 0.001, < 0.001, = 0003). Qualitative analysis also revealed significant differences in the mode of wash-out and fill-in direction between C-CEUS and H-CEUS in the malignant group (p = 0.041, 0.002). In addition, the homogeneity of enhancement showed significant differences between the two contrast models in the benign group (p = 0.009). Quantitative analysis indicated that the TIC parameters peak intensity (PI), deceleration time (DT) /2, area under the curve (AUC), and mean transition time (MTT) were significantly lower in the H-CEUS model compared to the C-CEUS model in both the benign and malignant groups. (all p < 0.001). In contrast, ascending slope of rise curve (AS) was significantly higher in the H-CEUS model compared to the C-CEUS model in the malignant group (p = 0.048).ConclusionsIn renal tumors, H-CEUS shows clearer internal enhancement of the mass and the changes in the wash-out period. The quantitative TIC parameters PI, DT/2, AUC, and MTT were lower in H-CEUS compared to C-CEUS. Both the quantitative and qualitative analyses indicated that H-CEUS better displays the characteristics of solid renal masses compared with C-CEUS.

Characteristics of gene expression in epicardial adipose tissue and subcutaneous adipose tissue in patients at risk for heart failure undergoing coronary artery bypass grafting

BackgroundEpicardial adipose tissue (EAT) surrounds the heart and is hypothesised to play a role in the development of heart failure (HF). In this study, we first investigated the differences in gene expression between epicardial adipose tissue (EAT) and subcutaneous adipose tissue (SAT) in patients undergoing elective coronary artery bypass graft (CABG) surgery (n = 21; 95% male). Secondly, we examined the association between EAT and SAT in patients at risk for HF stage A (n = 12) and in pre-HF patients, who show signs but not symptoms of HF, stage B (n = 9).ResultsThe study confirmed a distinct separation between EAT and SAT. In EAT 17 clusters of genes were present, of which several novel gene modules are associated with characteristics of HF. Notably, seven gene modules showed significant correlation to measures of HF, such as end diastolic left ventricular posterior wall thickness, e’mean, deceleration time and BMI. One module was particularly distinct in EAT when compared to SAT, featuring key genes such as FLT4, SEMA3A, and PTX3, which are implicated in angiogenesis, inflammation regulation, and tissue repair, suggesting a unique role in EAT linked to left ventricular dysfunction. Genetic expression was compared in EAT across all pre-HF and normal phenotypes, revealing small genetic changes in the form of 18 differentially expressed genes in ACC/AHA Stage A vs. Stage B.ConclusionsThe roles of subcutaneous and epicardial fat are clearly different. We highlight the gene expression difference in search of potential modifiers of HF progress. The true implications of our findings should be corroborated in other studies since HF ACC/AHA stage B patients are common and carry a considerable risk for progression to symptomatic HF.

Effect of Optimal Heart Rate on Left Ventricular Remodeling in Patients with Systolic Heart Failure Following Acute Coronary Syndrome.

The optimal therapeutic approach to facilitate reverse remodeling is desired in patients with systolic heart failure following acute coronary syndrome (ACS). The association between heart rate (HR) and reverse remodeling in this cohort has remained elusive.Patients with left ventricular ejection fraction (LVEF) < 50% who received echocardiography assessments following ACS were retrospectively included. Theoretically ideal HR was calculated using a previously established formula: 93 - 0.13 × (deceleration time [msec]). Impacts of HR on echocardiographic left ventricular (LV) reverse remodeling during the 2-year observational period were compared between 2 groups stratified by the HR difference between theoretically ideal and actual values: optimal HR group (HR difference ≤ 10 bpm) versus sub-optimal HR group (HR difference > 10 bpm).A total of 27 patients (median 72 years old, 23 males) were included. There were no significant differences in the baseline characteristics including maximum serum creatinine kinase level and the dose of beta-blocker between the 2 groups. LV ejection fraction increased significantly only in the optimal HR group at follow-up (from 42% to 54%; P = 0.001). The optimal HR group exhibited a more pronounced decrease in LV end-diastolic diameter (from 57 to 52 mm) compared to the sub-optimal HR group (from 58 to 56 mm).Optimal HR, which was calculated using a previously proposed formula, was associated with more substantial post-infarct LV reverse remodeling. The implications of aggressive HR modulation targeting theoretically ideal HR among those with systolic heart failure following ACS are the focus of our investigation here.

Association between left ventricular hypertrophy and the peak times of the R and P waves in hypertensive patients

Purpose: This study aimed to investigate the relationship between left ventricular hypertrophy (LVH), assessed by echocardiographic left ventricular mass index (LVMI), and electrocardiographically evaluated R wave peak time (RWPT) and P wave peak time (PWPT) in hypertensive patients. Materials and Methods: A cross-sectional study was conducted involving 100 hypertensive patients, excluding those with specific medical conditions. Clinical and demographic data were collected, and electrocardiographic and echocardiographic examinations were performed. RWPT and PWPT were assessed along with other parameters. Results: LVH was present in 33 out of 100 patients. Patients with LVH exhibited significantly higher RWPT (45.6 ± 4.9 vs. 35.0 ± 5.5) and PWPT (55.5 ± 15.8 vs. 49.1 ± 12.5) compared to those without LVH. Additionally, LVH patients showed increased left atrium anteroposterior diameter, and prolonged deceleration time. QRS fragmentation was more common in the LVH group. Conclusion: The study highlights the association between electrocardiographic parameters (RWPT and PWPT) and LVH in hypertensive patients. These findings underscore the potential utility of electrocardiogram as a non-invasive tool for LVH assessment in clinical practice in hypertensive patients, aiding in risk stratification and therapeutic decision-making.

Impact of prior aspirin use on left ventricular function in ST-elevation myocardial infarction patients undergoing primary percutaneous coronary intervention: An echocardiographic evaluation.

Previous studies have investigated the potential influence of prior aspirin use on cardiac function in patients with ST-elevation myocardial infarction (STEMI) who undergo primary percutaneous coronary intervention (PPCI). However, the results from these studies have been conflicting. This study aimed to investigate whether prior aspirin use affects left ventricular (LV) function in these patients using echocardiography. The study included 260 consecutive STEMI patients, who were divided into two groups based on the presence or absence of prior aspirin use. Echocardiographic parameters, such as maximal left atrial (LA) size, LV ejection fraction (LVEF), early diastolic velocity (e'), E/A ratio, and E/e' ratio, were assessed within 72 hours of admission. Aspirin users had an older age compared to non-users, as well as lower body mass index and renal function. They also had a greater history of hypertension and were more likely to be taking statins, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, and calcium channel blockers. There were no significant differences in LVEF, maximal LA size, E/A ratio, E/e' ratio, and deceleration time between aspirin users and non-users. e' wave was marginally lower in aspirin users (P=0.054). After controlling for confounding variables, the previous use of aspirin did not show a significant impact. Prior aspirin use in STEMI patients does not have a significant impact on LV echocardiographic parameters. Our conclusions remained consistent even after adjusting for potential confounders.

Acute effects of lower limb wearable resistance on horizontal deceleration and change of direction biomechanics.

This study aimed to investigate the acute effects of lower limb wearable resistance on maximal horizontal deceleration biomechanics, across two different assessments. Twenty recreationally trained team sport athletes performed acceleration to deceleration assessments (ADA), and 5-0-5 change of direction (COD) tests across three load conditions (unloaded, 2% of BW, 4% of body weight (BW)), with load attached to the anterior and posterior thighs and shanks. Linear mixed effect models with participant ID as the random effect, and load condition as the fixed effect were used to study load-specific biomechanical differences in deceleration mechanics across both tests. Primary study findings indicate that for the ADA, in the 4% BW condition, participants exhibited significantly greater degrees of Avg Approach Momentum, as well as significant reductions in deceleration phase center of mass (COM) drop, and Avg Brake Step ground contact deceleration (GCD) in both the 2% BW, and 4% BW condition, compared to the unloaded condition. In the 5-0-5 tests, participants experienced significant reductions in Avg Approach Velocity, Avg deceleration (DEC), and Stopping Time in the 4% BW condition compared to the unloaded condition. Similar to the ADA test, participants also experienced significant reductions in Avg Brake Step GCD in both the 2% BW and 4% BW conditions, and significant increases in Avg Approach Momentum in the 4% BW condition, compared to the unloaded condition. Therefore, findings suggest that based on the test, and metric of interest, the addition of lower limb wearable resistance led to acute differences in maximal horizontal deceleration biomechanics. However, future investigations are warranted to further explore if the use of lower limb wearable resistance could present as an effective training tool in enhancing athlete's horizontal deceleration and change of direction performance.

Constraining parameters for the accelerating universe in [formula omitted] gravity

In the paper, we present an accelerating cosmological model in f(R,Lm) gravity with the parameter constrained through the cosmological data sets. At the beginning, we have employed a functional form of f(R,Lm)=R2+αR2+Lmβ, where α and β are model parameters. This model is well motivated from the Starobinsky model in f(R) gravity and the power law form of f(Lm). The Hubble parameter has been derived with some algebraic manipulation and constrained by Hubble data and Pantheon+ data. With the constraint parameters, present value of deceleration parameter has been obtained to as q0≈−0.63 with the transition at zt≈0.7. It shows the early deceleration and late time acceleration behaviour. The present value of other geometric parameters such as the jerk and snap parameter are obtained to be j0≈0.78 and s0≈0.1 respectively. The state finder diagnostic test gives the quintessence behaviour at present and converging to ΛCDM at late times. Moreover the Om(z) diagnostics gives negative slope which shows that the model favours the state finder diagnostic result. Also the current age of Universe has been obtained as, t0=13.64Gyrs. The equation of state parameter also shows the quintessence behaviour. Based on the present analysis, it indicates that the f(R,Lm) gravitational theory may be another alternative to study the dark energy models.

Abstract P419: Left Ventricular Diastolic Dysfunction in Preeclamptic Patients: A Systematic Review and Meta-Analysis

Introduction: Preeclamptic (PE) patients are at a 4-fold higher risk for developing heart failure later in life. Pathological cardiac remodeling, and the ensuing left ventricular (LV) dysfunction during hypertensive pregnancy are thought to precede heart failure in these patients. Specifically, several observational studies employing echocardiography demonstrate exaggerated LV diastolic function alterations in PE patients suggestive of diastolic dysfunction. Objective: Thus, to consolidate the evidence supporting diastolic dysfunction in preeclampsia, we sought to systematically review the clinical literature, and conduct a meta-analysis on the pooled data pertaining to LV diastolic function. Methods: Three databases, MEDLINE (Ovid), Embase (Elsevier), and Scopus (Elsevier) were searched from inception to January 26, 2024 and the search results were uploaded to Covidence for screening. The diastolic function data—early diastole mitral flow to annulus velocity ratio (E/e’), isovolumic relaxation time (IVRT), early to late diastole mitral flow velocity ratio (E/A), and E wave deceleration time (DT)—were extracted, and subsequently used to perform meta-analysis using Cochrane’s RevMan Web (Mean Difference, MD; random effects models with inverse variance weighting). Results: A total of 63 from 5013 screened studies were eligible for inclusion and of these, only the studies reporting E/e’ (34/63), IVRT (18/63), E/A (38/63), and DT (16/63) were included in the meta-analysis. Our analysis showed that E/e’ is increased (MD of 2.33 [95% CI, 1.77 to 2.89], p&lt;0.00001) in PE patients when compared to healthy pregnant women indicating elevated LV filling pressures. Further, PE patients exhibited significantly higher IVRT (MD of 8.88 msec [95% CI, 6.07 to 11.68], p&lt;0.00001) and lower E/A (MD of -0.16 [95% CI, -0.25 to -0.06], p=0.001), collectively suggesting that the myocardial relaxation is impaired in preeclampsia. Interestingly, DT (MD of 3.10 msec [95% CI, -5.43 to 11.62], p=0.48) was not found to be different between the groups. Conclusions: Our findings demonstrate that PE patients develop LV diastolic dysfunction during pregnancy which may be mediated by hypertension caused pressure overload. Given that diastolic dysfunction is a hallmark characteristic of heart failure with preserved ejection fraction (HFpEF), future longitudinal studies examining cardiac function during pregnancy and postpartum will help determine if PE patients are destined to develop HFpEF.

Effect of Sevoflurane Anesthesia on Diastolic Function: A Prospective Observational Study.

The effect of sevoflurane on left ventricular diastolic function is not well understood. We hypothesized that parameters of diastolic function may improve under sevoflurane anesthesia in patients with preexisting diastolic dysfunction compared to patients with normal diastolic function. This observational study included 60 patients undergoing breast surgery or laparoscopic cholecystectomy. Patients were assigned to diastolic dysfunction (n = 34) or normal (n = 26) groups of septal e' < 8 or ≥ 8.0 cm/s on the first thoracic echocardiography (TTE) performed before anesthesia. During anesthesia, sevoflurane was maintained at 1 to 2 minimum alveolar concentration (MAC) to maintain the bispectral index at 40 to 50. At the end of surgery, the second TTE was performed under 0.8 to 1 MAC of sevoflurane with the patient breathing spontaneously without ventilator support. Primary end point was the percentage change (Δ) of e' on 2 TTEs (Δe'). Secondary end points were ΔE/e', Δleft atrial volume index (ΔLAVI), and Δtricuspid regurgitation maximum velocity (ΔTR Vmax). These percentage changes (Δ) were compared between diastolic dysfunction and normal groups. e' (Δe': 30 [6, 64] vs 0 [-18, 11]%; P < .001), mitral inflow E wave velocity (E), mitral inflow E/A ratio (E/A), and mitral E velocity deceleration time (DT) improved significantly in diastolic dysfunction group compared to normal group. LAVI decreased in diastolic dysfunction group but did not reach statistical significance between the 2 groups (ΔLAVI:-15 [-31, -3] vs -4 [-20, 10]%, P = .091). ΔE/e' was not different between the 2 groups (11 [-16, 26] vs 12 [-9, 22]%, P = .853) (all: median [interquartile range, IQR]). TR was minimal in both groups. In this study, echocardiographic parameters of diastolic function, including septal e', E, E/A, and DT, improved with sevoflurane anesthesia in patients with preexisting diastolic dysfunction, but remained unchanged in patients with normal diastolic function.

P227 MACROPHAGE TO MYOFIBROBLAST TRANSITION IN THE DEVELOPMENT OF DIASTOLIC DYSFUNCTION

Diastolic dysfunction (DD) and heart failure (HF) ravage a significant portion of the world's population. These end-stage diseases are most often precluded by hypertension (HTN). Cardiac fibrosis is one of the major factors in the degradation of cardiac function. There are multiple cellular players involved in fibrosis—including, macrophages. Indeed, in the past decade these cells have been shown to differentiate into professional fibrotic cells, myofibroblasts, a process termed macrophage to myofibroblast transition (MMT), in models of kidney injury. Despite this, the role of MMT in fibrotic remodeling in HTN and DD remains unknown. As such, we seek to investigate this phenomenon in the HTN heart and determine the role it plays in the pathological progression of HTN to DD. We utilized cardiac ultrasound and direct left ventricular (LV) pressure catheterization to gauge diastolic function. These gold-standard methods allowed us to assess cardiac function during HTN and investigate the heart at the transition to DD. Furthermore, flow cytometry was utilized to identify MMT cells (α-SMA+, CD68+) in the heart. These methods gave insight into the role that MMT plays in the degradation of heart function during HTN that inevitably leads to DD and HF. Cardiac ultrasound revealed that E/A and deceleration time (DcT) were greatly decreased in DOCA mice 10 days after the start of HTN. Further, LV pressure catheterization revealed decreased cardiac function, as shown by decreased -dp/dt. Finally, HTN and normal hearts were harvested and leukocytes isolated. Indeed α-SMA and CD68 staining showed a significant increase in MMT cells in the HTN heart. This study has shown a rapid onset of DD inside of DOCA + salt HTN mice. In addition, there was a significant increase of MMT cells in these same hearts, elucidating a novel mechanism of cardiac fibrosis. Future studies will aim to parse out the gravity of MMT in HTN to find new pharmaceutical targets against this debilitating disease.

Abstract P335: An innate immune component in hypertension-induced cardiac dysfunction Christoph Mora, Katherine Deck, Yunmeng Liu, Lance Benson, Tonya Rafferty, &amp; Shengyu Mu

Hypertension affects nearly half of American adults, inevitably leading to cardiac dysfunction and heart failure. Cardiac fibrosis is a major factor contributing to cardiac dysfunction during hypertension progression. However, the mechanisms involved in cardio-fibrogenesis remain to be elucidated. In the past decade, studies revealed that macrophages could differentiate into professional fibrotic cells, myofibroblasts, through a process termed macrophage to myofibroblast transition (MMT), helping maintain the integrity of major organs, such as the kidney. However, it is unknown whether MMT contributes to fibrotic remodeling in hypertensive hearts. Here, we aim to identify this phenomenon in the hearts of hypertensive animals and determine the role it plays in the pathological progression from hypertension to cardiac diastolic dysfunction. In this study we adopt the classic DOCA + Salt model of hypertension and utilized cardiac ultrasound and direct left ventricular (LV) pressure catheterization to gauge diastolic function. Heart sections from hypertensive and sham mice were stained with Masson’s trichrome to assess the extent of cardiac fibrosis. Furthermore, flow cytometry was utilized to identify MMT cells, which express both CD68 (monocytes) and α-SMA (myofibroblast) markers. These methods gave insight into the role that MMT plays in the degradation of heart function during hypertension. Direct left ventricle pressure catheter revealed that DOCA + salt mice exhibited impaired diastolic function. This result is supported by cardiac ultrasound showing that the compliance of the heart had significantly decreased, as evidenced by the lowering of the efferent/atrial (E/A) ratio and deceleration time (DcT). In addition to this evidence of mechanical cardiac degradation, leukocytes isolated from the heart and stained with macrophage and myofibroblast markers revealed a significant increase in CD68+ &amp; αSMA+ cells—a result reflected by increased fibrotic remodeling via Masson’s trichrome stain, in the hypertensive animals. This study demonstrated an onset of diastolic dysfunction in the heart of DOCA + salt hypertensive mice. Moreover, we found a positive association between MMT cells and fibrosis in the hearts of hypertensive animals. Future studies will aim to parse out both the gravity of MMT in hypertensive heart dysfunction and the mechanism by which macrophages undergo this transition to find new targets against this debilitating disease.

The Effectiveness of Warm-Up Using an Assistive Device in Wheelchair Basketball: A Feasibility Study of Able-Bodied Participants.

Introduction A warm-up is often performed to prevent injury and prepare for optimal performance. Nonetheless, research on its impact on performance, particularly in para-sports, remains limited. We hypothesized that the use of an assistive device during warm-up would enable wheelchair basketball players to perform full-body movements efficiently and effectively, contributing to enhanced wheelchair mobility. Therefore, this feasibility study aimed to assess the safety of warm-up exercise with an assistive device and the changes in wheelchair mobility performance before and after warm-up in able-bodied participants. Methods Thirteen able-bodied participants (nine males and four females; mean age: 34.3 ± 6.11 years) were analyzed. Warm-up consisted of a five-minute stand-up exercise using the lumbar-type Hybrid Assistive Limb®. Before and after warm-up, a 3-3-6 m sprint was performed as a wheelchair mobility performance test. The 3-3-6 m sprint is a test in which the athlete repeatedly accelerates, decelerates, and stops while driving at maximum effort for a total of 12 m (0-3 m, 3-6 m, and 6-12 m). The time required for the 3-3-6 m sprint and maximum instantaneous speed, acceleration time, deceleration time, hip joint angle, and average muscle activity of the lower limb and trunk muscles during the acceleration/deceleration phase of each section were compared before and after warm-up exercise. Results Warm-up with an assistive device was safe in healthy participants. The time required for the 3-3-6 m sprint was significantly reduced after the warm-up compared to that before the warm-up (p=0.005). Although not significant, there was a trend toward shorter deceleration times after the warm-up for participants herein. Conclusions In able-bodied participants, warm-up with an assistive device is safe; it may improve wheelchair mobility performance. Further research is required to determine its impact on para-athletes with disabilities.

Conventional and 2-Dimensional Speckle Tracking Echocardiography in Fabry Disease

Abstract OBJECTIVE To analyze the myocardial involvement and explore the strain characteristics of the left atrium and the left ventricle in patients with Fabry disease (FD) using conventional echocardiography and 2-dimensional speckle tracking echocardiography (2D-STE). METHODS A retrospective study was conducted. Sixty-nine patients with FD who were treated in the Department of Cardiology, Neurology and Nephrology of Peking University First Hospital from August 2014 to February 2023 and underwent echocardiography examination in the Cardiology Department were collected (FD group). During the same time, 69 age- and sex-matched individuals who had no cardiovascular, cerebrovascular, renal, metabolic, and autoimmune diseases, and had no obvious abnormalities on echocardiography were included in the control group. The clinical data and laboratory tests were collected, and routine echocardiography and 2D-STE were performed to analyze left atrial strain and left ventricular longitudinal strain. The differences in relevant parameters between groups were compared. RESULTS Compared with the control group, the patients in the FD group had smaller body mass index and body surface area, slower heart rate, poorer estimated glomerular filtration rate, and significantly increased brain natriuretic peptide and cardiac troponin I (all P &amp;lt; 0.05). E’med in the FD group was reduced (8.4 ± 3.4 vs. 9.9 ± 2.8, P = 0.006) and E peak, E peak deceleration time, pulmonary artery systolic pressure increased, interventricular septum and left ventricular posterior wall thickened, left ventricular mass index, and early diastolic transmitral inflow velocity/septal mitral annular velocity (E/Eʹ) increased (all P &amp;lt; 0.05). Compared with the control group, left atrial strains [including left atrial strain during reservoir phase (LASr), left atrial strain during contraction phase (LASct), left atrial strain during conduit phase (LAScd)] and left ventricular average global longitudinal strain (GLSavg) were reduced in the FD group. In the segmental longitudinal strain of the left ventricular, the strain was significantly reduced except for the strain of the basal and middle segment of the inferior wall (P &amp;lt; 0.05). CONCLUSIONS Patients with FD usually have multisystem involvement such as kidney and heart. Echocardiography usually shows varying degrees of myocardial hypertrophy and diastolic dysfunction, while left ventricular ejection fraction is normal. Left atrial strain, left ventricular global, and segmental longitudinal strain are all decreased to varying degrees.