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1,541 result(s) for "Diastole - physiology"
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Improving the diagnosis of heart failure in patients with atrial fibrillation
ObjectiveTo improve the echocardiographic assessment of heart failure in patients with atrial fibrillation (AF) by comparing conventional averaging of consecutive beats with an index-beat approach, whereby measurements are taken after two cycles with similar R-R interval.MethodsTransthoracic echocardiography was performed using a standardised and blinded protocol in patients enrolled in the RATE-AF (RAte control Therapy Evaluation in permanent Atrial Fibrillation) randomised trial. We compared reproducibility of the index-beat and conventional consecutive-beat methods to calculate left ventricular ejection fraction (LVEF), global longitudinal strain (GLS) and E/e’ (mitral E wave max/average diastolic tissue Doppler velocity), and assessed intraoperator/interoperator variability, time efficiency and validity against natriuretic peptides.Results160 patients were included, 46% of whom were women, with a median age of 75 years (IQR 69–82) and a median heart rate of 100 beats per minute (IQR 86–112). The index-beat had the lowest within-beat coefficient of variation for LVEF (32%, vs 51% for 5 consecutive beats and 53% for 10 consecutive beats), GLS (26%, vs 43% and 42%) and E/e’ (25%, vs 41% and 41%). Intraoperator (n=50) and interoperator (n=18) reproducibility were both superior for index-beats and this method was quicker to perform (p<0.001): 35.4 s to measure E/e’ (95% CI 33.1 to 37.8) compared with 44.7 s for 5-beat (95% CI 41.8 to 47.5) and 98.1 s for 10-beat (95% CI 91.7 to 104.4) analyses. Using a single index-beat did not compromise the association of LVEF, GLS or E/e’ with natriuretic peptide levels.ConclusionsCompared with averaging of multiple beats in patients with AF, the index-beat approach improves reproducibility and saves time without a negative impact on validity, potentially improving the diagnosis and classification of heart failure in patients with AF.
15 weeks of soccer training increases left ventricular mass and improves indices of left ventricular diastolic function in previously sedentary, mildly hypertensive, middle-aged women
PurposeTo investigate the impact of soccer training on cardiac adaptations in mildly hypertensive middle-aged women.MethodsHypertensive premenopausal women (n = 41; age (mean ± SD): 44 ± 7 years; height: 166 ± 6 cm; weight: 78.6 ± 11.6 kg; body fat: 43.3 ± 5.2%) were randomized to soccer training (SOC, n = 21) or control (CON, n = 20). SOC performed three weekly training sessions for 15 weeks, whereas CON had no training or lifestyle changes during the same period. Cardiac structure and function were assessed by echocardiography pre-intervention and post-intervention.ResultsSoccer training increased (P = 0.001) left ventricular mass index by 10% [95% CI 4; 15], while no changes occurred in CON (time × group interaction, P = 0.005). In addition, only SOC demonstrated a within-group increase (P = 0.01) of 8% [95% CI 2; 14] in left ventricular septum diameter. For markers of right ventricular remodelling, a within-group increase (P = 0.02) occurred for tricuspid annulus plane systolic excursion of 8% [95% CI 1; 14] in SOC only. Left atrial diameter index increased (P < 0.001) by 6% [95% CI 3; 10] after SOC, while it was unaffected in CON (time × group interaction, P = 0.02). For makers of diastolic function, SOC demonstrated a within-group increase (P = 0.02) in the average early diastolic mitral annulus velocity of 10% [95% CI 2; 19]. In addition, a reduction (P < 0.001) in mitral valve A velocity of − 19% [95% CI − 29; − 10] was observed following soccer training, which manifested in increased (P < 0.001) mitral valve E/A ratio of 34% [95% CI 16; 53] in SOC. No within-group changes were apparent in CON.ConclusionIn sedentary, mildly hypertensive, middle-aged women, 15 weeks of soccer training increases left ventricular mass and left atrial diameter and improves indices of left ventricular diastolic function.
The impact of obesity on left ventricular hypertrophy and diastolic dysfunction in children and adolescents
Childhood obesity continues to escalate worldwide and may affect left ventricular (LV) geometry and function. The aim of this study was to investigate the impact of obesity on prevalence of left ventricular hypertrophy (LVH) and diastolic dysfunction in children. In this analysis of prospectively collected cross-sectional data of children between 5 and 16 years of age from randomly selected schools in Peru, parameters of LV geometry and function were compared according to presence or absence of obesity (body mass index z-score > 2). LVH was based on left ventricular mass index (LVMI) adjusted for age and sex and defined by a z-score of > 2. LV diastolic function was assessed using mitral inflow early-to-late diastolic flow (E/A) ratio, peak early diastolic tissue velocities of the lateral mitral annulus (E′), early diastolic transmitral flow velocity to tissue Doppler mitral annular early diastolic velocity (E/E′) ratio, and left atrial volume index (LAVI). Among 1023 children, 681 children (mean age 12.2 ± 3.1 years, 341 male (50.1%)) were available for the present analysis, of which 150 (22.0%) were obese. LVH was found in 21 (14.0%) obese and in 19 (3.6%) non-obese children (p adjusted  < 0.001). LVMI was greater in obese than that in non-obese children (36.1 ± 8.6 versus 28.7 ± 6.9 g/m 2.7 , p < 0.001). The mean mitral E/E′ ratio and LAVI were significantly higher in obese than those in non-obese individuals (E/E′: 5.2 ± 1.1 versus 4.9 ± 0.8, p adjusted  = 0.043; LAVI 11.0 ± 3.2 versus 9.6 ± 2.9, p adjusted  = 0.001), whereas E′ and E/A ratio were comparable. Childhood obesity was associated with left ventricular hypertrophy and determinants of diastolic dysfunction. ClinicalTrials.gov Identifier: NCT02353663.
Effects of exercise countermeasure on myocardial contractility measured by 4D speckle tracking during a 21-day head-down bed rest
ObjectiveTo evaluate functional myocardial contractility after 21 days of head-down bed rest (HDBR) in sedentary control (CON) or with a resistive vibration exercise (RVE) countermeasure (CM) applied, by using 4D echocardiographic (4D echo) imaging and speckle tracking strain quantification.MethodsTwelve volunteers were enrolled in a crossover HDBR design, and 4D echo was performed in supine position (REST) at BDC-2 and at R + 2, and in − 6° HDT at day 18, and during the first and the last minute of the 80° head-up step of tilt test performed at both BDC-2 and R + 2. Radial (Rad-Str), longitudinal (Lg-Str) and twist (Tw-Str) strains were measured by 4D speckle tracking, as well as left ventricle diastolic volume (LVDV) and mass (LVmass).ResultsOn HDT 18: in the CON group, LVDV and LVmass were reduced (p < 0.05), the Rad-Str decreased (p < 0.05) and Tw-Str showed a tendency to increase (p < 0.11), with no changes in Lg-Str. In RVE group, LVDV and LV mass, as well as all the strain parameters remained unchanged. On R + 2: in the CON group, LVDV and LVmass were not recovered in all subjects compared to pre-HDBR (p < 0.08) and Rad-Str was still decreased (p < 0.05), while Tw-Str tended to increase (p < 0.09). These parameters remained unchanged in the RVE group. Tilt 80°: Rad-Str and Lg-Str values at 80° tilt were similar post-HDT in both groups.ConclusionThe 4D echo and speckle tracking analysis showed that in the CON group, Rad-Str decreased concomitant with LVmass and LVDV with HDBR, but this observation did not allow concluding if HDBR induced a real remodeling or a muscle atrophy. RVE was able to preserve LVmass, LVDV and contractility during HDBR, thus proving its effectiveness to this aim. Nevertheless, the significant HDBR-induced changes observed in the CON group had only a limited effect on the cardiac contractile response as observed during post-HDBR tilt test. The level of contractility at 80° Tilt position was not affected either by HDBR or by RVE CM.
Systolic and diastolic blood pressure time in target range and cardiovascular outcomes in patients with hypertension and pre‐frailty or frailty status
In patients with hypertension and pre‐frailty or frailty, the influence of systolic (SBP) and diastolic blood pressure (DBP) time in target range (TTR) on clinical outcomes is unclear. Thus, we conducted a post hoc analysis of the Systolic Blood Pressure Intervention Trial (SPRINT). Classifying 4208 participants into frail and non‐frail groups using a frailty index, the study calculated blood pressure time in target range (BP‐TTR) for the first three months using the Rosendaal method. The primary endpoint included a composite of nonfatal myocardial infarction (MI), acute coronary syndromes, stroke, acute decompensated heart failure (ADHF), and cardiovascular death. Relationships between BP‐TTR and outcomes were analyzed using Kaplan‐Meier curves, Cox models, and restricted cubic spline curves, with subgroup analysis for further insights. In a median follow‐up of 3.17 years, primary outcomes occurred in 6.7% of participants. Kaplan‐Meier analysis showed that a lower systolic blood pressure time in target range (SBP‐TTR) (0%–25%) correlated with an increased cumulative incidence of the primary outcome (p < .001), nonfatal MI (P = .021), stroke (P = .004), and cardiovascular death (P = .002). A higher SBP‐TTR (75%–<100%) was linked to a reduced risk of these outcomes. The restricted cubic spline (RCS) curve revealed a linear association between SBP‐TTR and the primary outcome (non‐linear P = .704). Similar patterns were observed for diastolic blood pressure time in target range (DBP‐TTR). Subgroup analysis showed that the protective effect of higher SBP‐TTR was less pronounced at low DBP‐TTR levels (P for interaction = .023). In conclusion, this study highlights the importance of maintaining BP within the target range to mitigate cardiovascular risks in this population.
Training-Induced Change of Diastolic Function in Heart Failure with Preserved Ejection Fraction
Abstract Aims Exercise training improves aerobic capacity (V̇O2peak) in patients with heart failure and preserved ejection fraction (HFpEF), but underlying mechanisms remain unclear. We aimed to evaluate whether exercise training could improve systolic and diastolic function during exercise. Methods This was a substudy of the multicentre Optimizing Exercise Training in HFpEF (OptimEx-Clin) trial, in which 180 patients with HFpEF were randomized 1:1:1 to guideline control, moderate continuous training or high-intensity interval training. All patients included at two out of five participating sites underwent exercise echocardiography at baseline and 3 months. Patients of both training groups were pooled and compared with guideline control. Results A total of 61 patients (mean age 73 ± 7 years, 72% female) were included. At baseline, E/e′ increased from 17.0 ± 5.7 to 19.5 ± 6.1 and systolic pulmonary artery pressure from 31 ± 8 to 51 ± 11 mmHg (both P < 0.001). Right ventricular function did not change significantly (maximal tricuspid annular plane systolic excursion 24.7 ± 4.0 mm, P = 0.051 vs. baseline). At 3 months, patients randomized to exercise training improved V̇O2peak (control +0.2, training +2.7 mL/kg/min, P = 0.006) and demonstrated small but significant improvements in exercise E/e′ (control 21.7 ± 7.5 to 22.8 ± 9.2, training 18.3 ± 5.0 to 17.2 ± 4.1, P = 0.044). No significant changes were observed in ejection fraction, mitral or tricuspid annular plane systolic excursion, S′, A′ or systolic pulmonary artery pressure (P > 0.05). Changes in E/e′ were not associated with the change in V̇O2peak. Conclusions In patients with HFpEF, exercise echocardiography revealed increases in filling pressures as well as a failure to augment right ventricular function during exercise. After 3 months of exercise training, HFpEF patients demonstrated a small improvement in diastolic function (exercise E/e′), but this did not explain the improved aerobic capacity. Training-induced change of diastolic function in HFpEF. HIIT, high-intensity interval training; HFpEF, heart failure with preserved ejection fraction; LVEF, left ventricular ejection fraction; MCT, moderate continuous training; TAPSE, tricuspid annular plane systolic excursion; V̇O2peak, peak oxygen uptake.
Diastolic left ventricular function in relation to the retinal microvascular fractal dimension in a Flemish population
Fractal analysis provides a global assessment of vascular networks (e.g., geometric complexity). We examined the association of diastolic left ventricular (LV) function with the retinal microvascular fractal dimension. A lower fractal dimension signifies a sparser retinal microvascular network. In 628 randomly recruited Flemish individuals (51.3% women; mean age, 50.8 years), we measured diastolic LV function by echocardiography and the retinal microvascular fractal dimension by the box-counting method (Singapore I Vessel Assessment software, version 3.6). The left atrial volume index (LAVI), e′, E/e′ and retinal microvascular fractal dimension averaged (±SD) 24.3 ± 6.2 mL/m 2 , 10.9 ± 3.6 cm/s, 6.96 ± 2.2, and 1.39 ± 0.05, respectively. The LAVI, E, e′ and E/e′ were associated ( P  < 0.001) with the retinal microvascular fractal dimension with association sizes (per 1 SD), amounting to −1.49 mL/m 2 (95% confidence interval, −1.98 to −1.01), 2.57 cm/s (1.31–3.84), 1.34 cm/s (1.07–1.60), and −0.74 (−0.91 to −0.57), respectively. With adjustments applied for potential covariables, the associations of E peak and E/e′ with the retinal microvascular fractal dimension remained significant ( P  ≤ 0.020). Over a median follow-up of 5.3 years, 18 deaths occurred. The crude and adjusted hazard ratios expressing the risk of all-cause mortality associated with a 1-SD increment in the retinal microvascular fractal dimension were 0.36 (0.23–0.57; P  < 0.001) and 0.57 (0.34–0.96; P  = 0.035), respectively. In the general population, a lower retinal microvascular fractal dimension was associated with greater E/e′, a measure of LV filling pressure. These observations can potentially be translated into new strategies for the prevention of diastolic LV dysfunction.
Association of left ventricular diastolic dysfunction with 24-h aortic ambulatory blood pressure: the SAFAR study
Aortic blood pressure (BP) and 24-h ambulatory BP are both better associated with target organ damage than office brachial BP. However, it remains unclear whether a combination of these two techniques would be the optimal methodology to evaluate patients’ BP in terms of left ventricular diastolic dysfunction (LVDD) prevention. In 230 participants, office brachial and aortic BPs were measured by a validated BP monitor and a tonometry-based device, respectively. 24-h ambulatory brachial and aortic BPs were measured by a validated ambulatory BP monitor (Mobil-O-Graph, Germany). Systematic assessment of patients’ LVDD was performed. After adjustment for age, gender, hypertension and antihypertensive treatment, septum and lateral E/Ea were significantly associated with office aortic systolic BP (SBP) and pulse pressure (PP) and 24-h brachial and aortic SBP and PP ( P ⩽0.04), but not with office brachial BP ( P ⩾0.09). Similarly, 1 standard deviation in SBP was significantly associated with 97.8±20.9, 86.4±22.9, 74.1±23.3 and 51.3±22.6 in septum E/Ea and 68.6±20.1, 54.2±21.9, 37.9±22.4 and 23.1±21.4 in lateral E/Ea, for office and 24-h aortic and brachial SBP, respectively. In qualitative analysis, except for office brachial BP, office aortic and 24-h brachial and aortic BPs were all significantly associated with LVDD ( P ⩽0.03), with the highest odds ratio in 24-h aortic SBP. Furthermore, aortic BP, no matter in the office or 24-h ambulatory setting, showed the largest area under receiver operating characteristic curves ( P ⩽0.02). In conclusion, 24-h aortic BP is superior to other BPs in the association with LVDD.
Sitagliptin improves diastolic cardiac function but not cardiorespiratory fitness in adults with type 2 diabetes
People with type 2 diabetes mellitus (T2D) have preclinical cardiac and vascular dysfunction associated with low cardiorespiratory fitness (CRF). This is especially concerning because CRF is a powerful predictor of cardiovascular mortality, a primary issue in T2D management. Glucagon-like pepetide-1 (GLP-1) augments cardiovascular function and our previous data in rodents demonstrate that potentiating the GLP-1 signal with a dipeptidyl peptidase-4 (DPP4) inhibitor augments CRF. Lacking are pharmacological treatments which can target T2D-specific physiological barriers to exercise to potentially permit adaptations necessary to improve CRF and thereby health outcomes in people with T2D. We therefore hypothesized that administration of a DPP4-inhibitor (sitagliptin) would improve CRF in adults with T2D. Thirty-eight participants (64 ± 1 years; mean ± SE) with T2D were randomized in a double-blinded study to receive 100 mg/day sitagliptin, 2 mg/day glimepiride, or placebo for 3 months after baseline measurements. Fasting glucose decreased with both glimepiride and sitagliptin compared with placebo (P = 0.002). CRF did not change in any group (Placebo: Pre: 15.4 ± 0.9 vs. Post: 16.1 ± 1.1 ml/kg/min vs. Glimepiride: 18.5 ± 1.0 vs. 17.7 ± 1.2 ml/kg/min vs. Sitagliptin: 19.1 ± 1.2 vs. 18.3 ± 1.1 ml/kg/min; P = 0.3). Sitagliptin improved measures of cardiac diastolic function, however, measures of vascular function did not change with any treatment. Three months of sitagliptin improved diastolic cardiac function, however, CRF did not change. These data suggest that targeting the physiological contributors to CRF with sitagliptin alone is not an adequate strategy to improve CRF in people with T2D. www.clinicaltrials.gov NCT01951339.
High-Intensity Intermittent Swimming Improves Cardiovascular Health Status for Women with Mild Hypertension
To test the hypothesis that high-intensity swim training improves cardiovascular health status in sedentary premenopausal women with mild hypertension, sixty-two women were randomized into high-intensity (n=21; HIT), moderate-intensity (n=21; MOD), and control groups (n=20; CON). HIT performed 6–10 × 30 s all-out swimming interspersed by 2 min recovery and MOD swam continuously for 1 h at moderate intensity for a 15-week period completing in total 44±1 and 43±1 sessions, respectively. In CON, all measured variables were similar before and after the intervention period. Systolic BP decreased (P<0.05) by 6±1 and 4±1 mmHg in HIT and MOD; respectively. Resting heart rate declined (P<0.05) by 5±1 bpm both in HIT and MOD, fat mass decreased (P<0.05) by 1.1±0.2 and 2.2±0.3 kg, respectively, while the blood lipid profile was unaltered. In HIT and MOD, performance improved (P<0.05) for a maximal 10 min swim (13±3% and 22±3%), interval swimming (23±3% and 8±3%), and Yo-Yo IE1 running performance (58±5% and 45±4%). In conclusion, high-intensity intermittent swimming is an effective training strategy to improve cardiovascular health and physical performance in sedentary women with mild hypertension. Adaptations are similar with high- and moderate-intensity training, despite markedly less total time spent and distance covered in the high-intensity group.