Effect of a 1-hour single bout of moderate-intensity exercise on fat oxidation kinetics

The present study aimed to examine the effects of a prior 1-hour continuous exercise bout (CONT) at an intensity (Fat_max) that elicits the maximal fat oxidation (MFO) on the fat oxidation kinetics during a subsequent submaximal incremental test (IncrC). Twenty moderately trained subjects (9 men and 11 women) performed a graded test on a treadmill (Incr), with 3-minute stages and 1-km·h⁻¹ increments. Fat oxidation was measured using indirect calorimetry and plotted as a function of exercise intensity. A mathematical model (SIN) including 3 independent variables (dilatation, symmetry, and translation) was used to characterize the shape of fat oxidation kinetics and to determine Fat_max and MFO. On a second visit, the subjects performed CONT at Fat_max followed by IncrC. After CONT performed at 57% ± 3% (means ± SE) maximal oxygen uptake (V?o_2max), the respiratory exchange ratio during IncrC was lower at every stage compared with Incr (P < .05). Fat_max (56.4% ± 2.3% vs 51.5% ± 2.4% V?o_2max, P = .013), MFO (0.50 ± 0.03 vs 0.40 ± 0.03 g·min⁻¹, P < .001), and fat oxidation rates from 35% to 70% V?o_2max (P < .05) were significantly greater during IncrC compared with Incr. However, dilatation and translation were not significantly different (P > .05), whereas symmetry tended to be greater in IncrC (P = .096). This study showed that the prior 1-hour continuous moderate-intensity exercise bout increased Fat_max, MFO, and fat oxidation rates over a wide range of intensities during the postexercise incremental test. Moreover, the shape of the postexercise fat oxidation kinetics tended to have a rightward asymmetry.     

Relationships between diet and basal fat oxidation and maximal fat oxidation during exercise in sedentary adults

Background and aimsTo study the relationships between different dietary factors (i.e., energy, macronutrient and fatty acid intake, food group consumption, and dietary pattern) and basal fat oxidation (BFox) and maximal fat oxidation during exercise (MFO) in sedentary adults.Method and resultsA total of 212 (n = 130 women; 32.4 ± 15.1 years) sedentary healthy adults took part in the present study. Information on the different dietary factors examined was gathered through a food frequency questionnaire and three nonconsecutive 24 h recalls. Energy and macronutrient intakes and food consumption were then estimated and dietary patterns calculated. BFox and MFO were measured by indirect calorimetry following standard procedures. Our study shows that dietary fiber intake was positively associated with BFox after taking into consideration the age, sex, and energy intake. A significant positive association between nut consumption and BFox was observed, which became nonsignificant after taking into consideration the age and energy intake. Fat intake and the dietary quality index (DQI), and the DQI for the Mediterranean diet were positively associated with MFO, which was attenuated after taking sex, age, and energy intake into consideration.ConclusionA higher dietary fiber intake and fat intake are associated with higher BFox and MFO, respectively, in sedentary adults.Clinical trialsClinicalTrials.gov, ID: NCT02365129 (https://clinicaltrials.gov/ct2/show/study/NCT02365129) & ID: NCT03334357 (https://clinicaltrials.gov/ct2/show/NCT03334357).     

Too Little of a Good Thing: Strong Associations Between Cardiac Size and Fitness Among Women

BackgroundCardiorespiratory fitness (CRF) is associated with functional impairment and cardiac events, particularly heart failure (HF). However, the factors predisposing women to low CRF and HF remain unclear.ObjectivesThis study sought to evaluate the association between CRF and measures of ventricular size and function and to examine the potential mechanism linking these factors.MethodsA total of 185 healthy women aged >30 years (51 ± 9 years) underwent assessment of CRF (peak volume of oxygen uptake [Vo₂peak]) and biventricular volumes at rest and during exercise by using cardiac magnetic resonance (CMR). The relationships among Vo₂peak, cardiac volumes, and echocardiographic measures of systolic and diastolic function were assessed using linear regression. The effect of cardiac size on cardiac reserve (change in cardiac function during exercise) was assessed by comparing quartiles of resting left ventricular end-diastolic volume (LVEDV).ResultsVo₂peak was strongly associated with resting measures of LVEDV and right ventricular end-diastolic volume (R² = 0.58-0.63; P < 0.0001), but weakly associated with measures of resting left ventricular (LV) systolic and diastolic function (R² = 0.01-0.06; P < 0.05). Increasing LVEDV quartiles were positively associated with cardiac reserve, with the smallest quartile showing the smallest reduction in LV end-systolic volume (quartile [Q]1: −4 mL vs Q4: −12 mL), smallest augmentation in LV stroke volume (Q1: +11 mL vs Q4: +20 mL) and cardiac output (Q1: +6.6 L/min vs Q4: +10.3 L/min) during exercise (interaction P < 0.001 for all).ConclusionsA small ventricle is strongly associated with low CRF because of the combined effect of a smaller resting stroke volume and an attenuated capacity to increase with exercise. The prognostic implications of low CRF in midlife highlight the need for further longitudinal studies to determine whether women with small ventricles are predisposed to functional impairment, exertional intolerance, and HF later in life.     

Association of Meteorin-Like Hormone with insulin resistance and body composition in healthy Iranian adults

Background and aimsSedentary behavior and/or physical inactivity are modifiable risk factors for noncommunicable diseases. Myokines are one of the mediators of physical activity health benefits. Relationship between regular physical activity (RPA) and baseline plasma Meteorin-Like Hormone (Metrnl) has not been explored in human. Hence, we compared baseline plasma Metrnl between sedentary individuals and ones with recreational physical activities, and role of Metrnl as a biological messenger between physical activity and insulin resistance and body composition was also explored.MethodsForty healthy young men (aged: 21 ± 2.1 yrs; BMI: 23 ± 3.44 kg/m²) completed the study. Participants were equally assigned into two groups of control (sedentary) and case (recreational athletes). Baseline plasma Metrnl, glucose, insulin and body composition components and insulin resistance index (HOMA-IR) were assessed under resting conditions.ResultsExcept for baseline blood glucose, baseline plasma Metrnl, insulin, HOMA-IR and body mass index and body fat percentage were similar between two groups (P > 0.05). However, after Metrnl correction for the degree of insulin resistance index (Metrnl/HOMA-IR), recreational athletes showed a significantly greater baseline compared to sedentary subjects (P < 0.05). Baseline blood glucose showed a negative and significant correlation with baseline plasma Metrnl (P < 0.05).ConclusionsBaseline plasma Metrnl is correlated with regular physical activity and insulin sensitivity, but not with body composition parameters. Metrnl may be one possible mediator of the beneficial effects of PA on insulin sensitivity in healthy humans. Hence, increasing awareness of the benefits of physical activity and incorporating physical activity into lifestyle are of great importance for people with non-communicable diseases.     

Exercise‐Induced Pulmonary Hypertension in Scleroderma Patients: A Common Finding but with Elusive Pathophysiology

Background: The etiology of exercise‐induced pulmonary hypertension (exPH) in systemic sclerosis (SSc) remains a complex task, as both left ventricle (LV) diastolic dysfunction and pulmonary vascular disease can contribute to its development. We determined the incidence of exPH in SSc and examined the association between pulmonary artery systolic pressure (PASP) and tissue Doppler‐derived indexes of pulmonary capillary wedge pressure (PCWP). Methods: Thirty‐eight patients with SSc were studied, using a cycloergometer protocol; 10 were excluded due to resting PH or absence of tricuspid regurgitation (TR); TR and mitral E‐wave velocities, LV outflow tract time‐velocity integral and LV septal E′‐wave were measured before and in peak exercise to calculate cardiac output (CO), PCWP and pulmonary vascular resistance (PVR). Results: Mean age of diagnosis was 57.9 ± 8.9 years. At a mean workload of 64 ± 29 Watts, 48% of patients increased PASP ≥ 50 mmHg. PCWP, assessed by the E/e′ ratio, did not change significantly during exercise (10.2 ± 3.1–10.0 ± 5.1; P = NS). Only 3 patients had elevations of the E/e′ ratio ≥ 13 during exercise; 2 of them had an exercise PASP ≥ 50 mmHg, yielding a proportion of exPH due to elevated LV filling pressures of 2/11 (18%). Patients with exPH had lower DL_CO and had more frequently the diffuse SSc. Conclusion: The elevation of PASP during exercise in most patients of this cohort seems to be related to a reduced pulmonary vascular reserve, and not to an increase in PCWP. Further studies are warranted to determine the therapeutic, as well as prognostic implications of these findings.     

Potassium excretion and blood pressure are associated with heart rate variability in healthy black adults: The African-PREDICT study

Background and aimsHeart rate variability (HRV) is a main determinant of autonomic function and related to the development of hypertension and cardiovascular (CV) disease. Hypertension develops in black populations at an earlier age, which could be due to differences in the autonomic nervous system activity and sodium/potassium handling in black and white populations. We investigated whether HRV is associated with 24 h urinary sodium and potassium excretion and blood pressure (BP) in a young bi-ethnic cohort.Methods and resultsWe examined 423 black and 483 white healthy adults (aged 24.5 ± 3.1 years) for 24 h HRV, including standard deviation of normal RR intervals (SDNN) reflecting autonomic variations over time, and root mean square of successive differences (RMSSD) reflecting parasympathetic activity. We measured 24 h urinary sodium and potassium concentration and BP. The black group had lower SDNN and potassium excretion as well as higher RMSSD, sodium and Na/k ratio compared to the white group (all p < 0.05). Only in black individuals, urinary potassium excretion was independently and negatively associated with SDNN (β[95% CI];-0.26[-0.50;-0.02]ms) and RMSSD (?0.14[-0.27;-0.01]ms, p < 0.05). One unit increase in sodium/potassium (Na/K) ratio was associated with higher SDNN (β[95% CI]; 3.04[0.89; 5.19]ms) and RMSSD (1.60[0.41; 2.78]ms) in the black cohort only (both p < 0.001). In both groups elevated 24 h diastolic BP was associated with lower RMSSD (p < 0.05).ConclusionLower potassium excretion and higher Na/K ratio related independently to higher HRV in young and healthy black adults. A better ethnic-specific understanding of sodium and potassium handling is required as part of preventive cardiology, especially in black individuals.Clinical trial registrationClinicalTrials.gov Identifier: NCT03292094; URL: https://clinicaltrials.gov/ct2/show/NCT03292094.     

Eight weeks of moderate-intensity exercise training increases heart rate variability in sedentary postmenopausal women

Background

Regular exercise is associated with increased heart rate variability (HRV). However, results from studies examining the effect of exercise training on HRV in postmenopausal women are inconclusive. In addition, the effect of hormone replacement therapy (HRT) on HRV remains a subject of speculation.

Methods

We examined 88 sedentary postmenopausal women in a randomized controlled trial who were assigned to exercise (n = 49) or control (n = 39) groups. The exercising women performed 8 weeks of aerobic exercise training at a heart rate equivalent to 50% of VO_2max, consisting on average of 44 minutes per session, 3 to 4 times per week. Resting HRV was measured in each participant at baseline and after 8 weeks of intervention. Ten minutes of resting R-R intervals were analyzed by time (standard deviation of mean R-R intervals, root of mean square successive differences) and frequency domain methods: low-frequency (LF) was defined as 0.04 to 0.15 Hz, high-frequency (HF) as 0.15 to 0.40 Hz, and total spectral power as 0.00 to 0.40 Hz. The LF and HF components in normalized units were also calculated.

Results

At baseline, there were no significant differences in HRV between control and exercise groups. Additionally, there were no differences in any HRV variables when women were grouped by HRT use (no HRT, estrogen-only HRT, and progestin-containing HRT). After 8 weeks, women randomly assigned to the exercise group increased all absolute time and frequency domain indexes (all P < .001) and reduced resting heart rate (P = .002) compared with women in the control group. The LF and HF components expressed as normalized units remained unchanged after exercise intervention. Additionally, HRT use did not modify the exercise-induced changes in HRV.

Conclusions

We conclude that moderate aerobic exercise increases HRV in sedentary postmenopausal women. This benefit is not influenced by the use of HRT.     

Utility of E/e′ Ratio During Low-Level Exercise to Diagnose Heart Failure With Preserved Ejection Fraction

BackgroundE/e′ ratio during exercise is the key parameter in identifying elevated pulmonary capillary wedge pressure (PCWP), and thus heart failure with preserved ejection fraction (HFpEF). However, its diagnostic value is limited when mitral inflow or tissue velocities are fused during elevated heart rate.ObjectivesThe authors hypothesized that E/e‘ ratio during low-level (20 W) exercise (E/e′_20W) can help diagnose HFpEF.MethodsErgometric exercise stress echocardiography was performed in 215 dyspneic patients with an EF ≥50%. The authors determined the feasibility of E/e′ ratio at each stage (frequency of patients who had measurable E/e′ without E-A fusion among 215 participants) and examined whether E/e′_20W could predict normal E/e′ ratio during peak exercise (E/e′_peak ≤15). The authors also evaluated whether E/e′_20W could predict normal PCWP during exercise (PCWP <25 mm Hg) in a subset of participants (n = 45) who underwent exercise right heart catheterization.ResultsThe feasibility of the E/e′ ratio decreased from 100% at rest to 96.3% during 20-W exercise and 74.9% during peak exercise caused by E-A fusion. In patients with E/e′_peak >15, there was an increase in E/e′ ratio from rest to 20-W exercise (11.2 ± 2.1 to 16.3 ± 3.5; P < 0.0001), but it did not change significantly from 20-W exercise to peak exercise (P = 0.12). E/e′_20W predicted E/e′_peak ≤15 (AUC: 0.91; P < 0.0001) with the cutoff value of ≤12.4 showing high specificity (94%) and positive predictive value (98%). During 20-W exercise, 93% of the HFpEF patients developed PCWP ≥25 mm Hg. E/e′_20W predicted normal PCWP during exercise (AUC: 0.77; P = 0.01) with the cutoff value of ≤12.4 showing high specificity (83%).ConclusionsE/e′ ratio during low-level exercise is highly feasible and predicts normal E/e′ ratio or PCWP during peak exercise with high specificity. These data suggest that E/e′_20W could be used as an alternative to the peak exercise value to rule out HFpEF in patients with dyspnea.     

Clinical significance of heart rate variability for the monitoring of cardiac autonomic neuropathy in end-stage renal disease patients

Background and aimsThe aim of this study is to determine whether the measurement of continuous heart rate variability (HRV) is useful in the evaluation of cardiac autonomic neuropathy (CAN) in end-stage renal disease (ESRD) patients.Methods and resultsThis cross-sectional study was performed at Seoul St. Mary's hospital between June 2017 and February 2018. Seventy-seven ESRD patients, and 29 healthy controls (HCs) were asked to wear a continuous ambulatory HRV monitor for 24 h. General cardiac function was evaluated using transthoracic echocardiogram (TTE), pulse wave velocity (PWV), coronary calcium scoring (CCS), and 24-h ambulatory blood pressure monitoring (ABPM). HRV parameters of ESRD patients and HCs, and the correlation of HRV parameters with cardiovascular screening methods were observed. All HRV parameters were significantly decreased in ESRD patients compared to HCs (P < 0.001). In the correlation analysis between TTE results and HRV parameters, 24-h standard deviation of all N–N intervals (24SDNN), 24-h standard deviation of sequential 5-min N–N interval means (24DANN) and Low Frequency Power/High Frequency Power (LF/HF) ratio showed negative correlations with E/e’, LAVI and TR velocity which are representative indices for the diastolic function of the heart (P < 0.05). HRV parameters showed negative correlations with baPWV, CCS, and 24-h ABPM results as well (P < 0.05). Hemoglobin and serum albumin showed positive correlations with HRV parameters, and glucose, BUN, creatinine, and iPTH levels showed negative correlations (P < 0.05).ConclusionContinuous HRV monitoring may be a useful tool for the evaluation of CAN in ESRD.     

Elevated serum uric acid is associated with incident hypertension in the health according to various contemporary blood pressure guidelines

Background and aimsElevated serum uric acid (SUA) is associated with hypertension according to its traditional definition. We investigated the association between SUA and incident hypertension according to the European Society of Cardiology (ESC) and American Society of Cardiology (ACC) guidelines.Methods and resultsIn this retrospective cohort study, we enrolled 10,537 healthy individuals ≥30 years old who underwent a routine annual health examination with office blood pressure recorded at our hospital in 2016; of the participants, 7349 repeated the exam in 2017. According to the ESC and ACC guidelines, hypertension was defined as office BP ≥ 140/90 mmHg or ≥130/80 mmHg. Hyperuricemia (HUA) was defined as SUA ≥7 mg/dL in men and ≥6 mg/dL in women. The hypertension incidence was 5.8% among 6378 individuals in the ESC cohort and 19% among 4330 individuals in the ACC cohort. Incident hypertension was significantly more common in the hyperuricemic group than in the normouricemic group (ESC: 8.6% vs. 4.7%, P < 0.001; ACC: 25.5% vs. 16.9%, P < 0.001). In the fully adjusted multivariate logistic regression analyses, each increase in SUA was associated with an increase in incident hypertension risk (ESC: adjusted OR: 1.167, 95% CI: 1.061–1.284, P = 0.001; ACC: adjusted OR: 1.125, 95% CI: 1.044–1.213, P = 0.002). The association can be explained by a significant correlation of baseline SUA with the BP in the following year (r = 0.24, P < 0.001 for baseline SUA and SBP in the following year; r = 0.239, P < 0.001 for baseline SUA and DBP in the following year).ConclusionElevated SUA was associated with incident hypertension in healthy individuals according to various contemporary BP guidelines (ClinicalTrials.gov: NCT03473951).Clinical trialsClinicalTrials.gov with the identification number of NCT03473951.     

Noninvasive ventilation can modulate heart rate variability during high-intensity exercise in COPD-CHF patients

Objectiveto assess the acute effects of non-invasive ventilation (NIV) during high-intensity exercise on heart rate variability (HRV) responses in chronic obstructive pulmonary disease (COPD) and Chronic heart failure (CHF) patients.MethodsThis was randomized, double blinded and controlled study. Fourteen patients with COPD-HF diagnosis were evaluated. The subjects underwent to the following tests: (I) cardiopulmonary exercise testing (CPET) on a cycle ergometer ramp protocol; (II) 7 days after CPET, patients randomly underwent two constant-load exercise (CLE) with NIV or Sham ventilation until tolerance limit, with 80% of the CPET peak load. R-R intervals (RRi) were continuously collected during rest, exercise and in recovery. Time and frequency domain and nonlinear heart rate variability (HRV) indices were obtained.ResultsNIV resulted in a decrease of Mean iRR, square root of the mean squared differences of successive RRi (rMSSD), RR tri index and high-frequency (HF), nu (p < 0.05) and increase of Mean HR, low-frequency (LF), nu and LF/HF (p < 0.05) during exercise when compared to rest. In addition, NIV during exercise induced lower rMSSD and Sample Entropy when compared with Sham (p < 0.05). Negative correlation was found between forced expiratory volume in 1 second (FEV_1, L) vs HF (nu) during exercise with NIV (p = 0.04; r= -0.58). Furthermore, simple linear regression showed that the FEV₁ (L) affected 30% of the HF (nu) response during the exercise with NIV.ConclusionNIV during exercise produced enhanced heart rate and autonomic responses in COPD-CHF patients. Additionally, COPD severity is negatively associated with a higher vagal response during exercise with NIV.     

Pancreatic resection in the pediatric,adolescent and young adult population: nationwide analysis on complications

BackgroundThe aim of this study was to determine pancreatic surgery specific short- and long-term complications of pediatric, adolescent and young adult (PAYA) patients who underwent pancreatic resection, as compared to a comparator cohort of adults.MethodsA nationwide retrospective cohort study was performed in PAYA patients who underwent pancreatic resection between 2007 and 2016. PAYA was defined as all patients <40 years at time of surgery. Pancreatic surgery-specific complications were assessed according to international definitions and textbook outcome was determined.ResultsA total of 230 patients were included in the PAYA cohort (112 distal pancreatectomies, 99 pancreatoduodenectomies), and 2526 patients in the comparator cohort. For pancreatoduodenectomy, severe morbidity (29.3% vs. 28.6%; P = 0.881), in-hospital mortality (1% vs. 4%; P = 0.179) and textbook outcome (62% vs. 58%; P = 0.572) were comparable between the PAYA and the comparator cohort. These outcomes were also similar for distal pancreatectomy. After pancreatoduodenectomy, new-onset diabetes mellitus (8% vs. 16%) and exocrine pancreatic insufficiency (27% vs. 73%) were lower in the PAYA cohort when compared to adult literature.ConclusionPancreatic surgery-specific complications were comparable with patients ≥40 years. Development of endocrine and exocrine insufficiency in PAYA patients who underwent pancreatoduodenectomy, however, was substantially lower compared to adult literature.     

Disrupted white matter integrity in the brain of type 1 diabetes is associated with peripheral neuropathy and abnormal brain metabolites

AimsWe aimed to quantify microstructural white matter abnormalities using magnetic resonance imaging and examine their associations with 1) brain metabolite and volumes and 2) clinical diabetes-specific characteristics and complications in adults with type 1 diabetes mellitus (T1DM) and distal symmetric peripheral neuropathy (DSPN).MethodsDiffusion tensor images (DTI) obtained from 46 adults with T1DM and DSPN and 28 healthy controls were analyzed using tract-based spatial statistics and were then associated with 1) brain metabolites and volumes and 2) diabetes-specific clinical characteristics (incl. HbA_1c, diabetes duration, level of retinopathy, nerve conduction assessment).ResultsAdults with T1DM and DSPN had reduced whole-brain FA skeleton (P = 0.018), most prominently in the inferior longitudinal fasciculus and retrolenticular internal capsule (P < 0.001). Reduced fractional anisotropy (FA) was associated with lower parietal N-acetylaspartate/creatine metabolite ratio (r = 0.399, P = 0.006), brain volumes (P ≤ 0.002), diabetes duration (r = ?0.495, P < 0.001) and sural nerve amplitude (r = 0.296, P = 0.046). Additionally, FA was reduced in the subgroup with concomitant proliferative retinopathy compared to non-proliferative retinopathy (P = 0.03). No association was observed between FA and HbA_1c.ConclusionsThis hypothesis-generating study provided that altered white matter microstructural abnormalities in T1DM with DSPN were associated with reduced metabolites central for neuronal communications and diabetes complications, indicating that peripheral neuropathic complications are often accompanied by central neuropathy.     

Tonic sympathetic support of metabolic rate is attenuated with age, sedentary lifestyle, and female sex in healthy adults

We recently demonstrated in young adult humans that the sympathetic nervous system contributes to the control of resting metabolic rate via tonic beta-adrenergic receptor stimulation. In the present follow-up study we determined the respective effects of age, habitual exercise status, and sex on this regulatory mechanism. Resting metabolic rate (ventilated hood, indirect calorimetry) was determined in 55 healthy sedentary or endurance exercise-trained adults, aged 18-35 or 60-75 yr (29 men and 26 women), before (baseline) and during the infusion of either a nonselective beta-adrenergic receptor antagonist (propranolol) or saline (control). Relative to baseline values, during beta-adrenergic receptor antagonism resting metabolic rate adjusted for fat-free mass was reduced to a lesser extent in older (mean +/- SE, -130 +/- 46 kJ/d) compared with young (-297 +/- 46) adults, sedentary (-151 +/- 50) compared with endurance exercise-trained (-268 +/- 46) adults, and women (-105 +/- 33) compared with men (-318 +/- 50; all P < 0.01). Reductions in resting metabolic rate during beta-adrenergic receptor antagonism were positively related to higher baseline resting metabolic rate and plasma catecholamine concentrations and negatively related to adiposity (all P < 0.05). Resting metabolic rate was unchanged in response to saline control in all groups. These results provide experimental support for the hypothesis that aging, sedentary living, and female sex are associated with attenuated sympathetic nervous system support of resting metabolic rate in healthy adult humans.     

Relationship between Cutoff Values of Peak Aortic Valve Velocity and Those of Other Doppler Echocardiographic Parameters of Severity in Patients with Aortic Stenosis and Normal Flow

Background: Previous studies have reported inconsistencies between echocardiographic parameters of severity in aortic valve stenosis (AS). Peak aortic valve velocity (V_max) strongly predicts outcome in AS patients. This study was therefore designed to identify the cutoff values of echocardiographic parameters of severity corresponding to a V_max ≥ 3 m/sec, ≥4 m/sec, 5 m/sec, or 5.50 m/sec in a large cohort of patients with normal flow (NF) AS. Methods and Results: We retrospectively reviewed the echocardiograms of 528 consecutive patients with normal flow (NF) AS, left ventricular (LV) ejection fraction ≥0.50, and NF (stroke volume index > 35 mL/m²). The values of mean pressure gradient (MPG), aortic valve area (AVA), and indexed aortic valve area (IAVA) corresponding to V_max ≥ 3 m/sec obtained from receiver operating characteristic (ROC) curves analysis were 22 mmHg, 1.15 cm², and 0.60 cm²/m², respectively. While a cutoff of V_max ≥ 4 m/sec to define severe AS was consistent with a value of 39 mmHg for MPG, corresponding values for AVA and IAVA of 0.90 cm² and 0.48 cm²/m², respectively, were substantially different from those recommended in current guidelines. MPG ≥60 and 65 mmHg, AVA ≤0.76 and ≤0.68 cm², and IAVA ≤0.41 and ≤0.35 cm²/m² were related to a V_max ≥5 and ≥5.5 m/sec (very severe AS), respectively. Conclusions: Guidelines recommended cutoff values for AVA and IAVA are not consistent with those of V_max and MPG. The results of this study may serve as safeguard in case of apparent inconsistencies between echocardiographic parameters of severity in NF AS.     

Hemodynamic Response to Rapid Saline Infusion Compared with Exercise in Healthy Participants Aged 20–80 Years

Background and ObjectiveRapid saline infusion and exercise has been proposed as methods to unmask cardiovascular disease. However, the normal hemodynamic response to rapid saline infusion has not been compared to exercise nor is it known whether the responses are age-dependent.We assessed the hemodynamic response to rapid saline infusion in healthy participants over a wide age-range and compared it to exercise in the same participants.Methods and resultsFifty healthy participants (young <40 years, n = 16, middle-aged 40–59 years, n = 15, elderly 60–80 years, n = 19) underwent right heart catheterization at rest, during semisupine ergometer exercise at three exercise levels (25%, 50%, and 75% of peak VO₂) and after rapid saline infusion (10 ml/kg at a rate of 150 ml/min). Rapid saline infusion significantly increased pulmonary capillary wedge pressure (PCWP) similarly across all age groups (∆PCWP 6 ± 2; 7 ± 2; 6 ± 4 mmHg for the young, middle-aged and elderly respectively) with no correlation between age and ∆PCWP (r = 0.05; p = 0.74). However, there was a negative correlation between age and ∆stroke volume (SV) as elderly participants had a lower increase in SV following rapid saline infusion (r = 0.44; p = 0.002). On the contrary, exercise-induced significantly larger and age-dependent increases in PCWP (r = 0.58; p < 0.0001). Exercise also caused a larger increase in SV compared with rapid fluid loading (p = 0.0003)ConclusionUnlike exercise, rapid saline infusion caused an age-independent increase in PCWP in healthy adults. Suggesting that age-related impairments beyond passive stiffness have a greater impact on exercise-induced increase in PCWP.Clinical trial registrationhttps://clinicaltrials.gov/ct2/show/NCT01974557     

Independent effects of diet and exercise training on fat oxidation in non-alcoholic fatty liver disease

AIM To investigate the independent effects of 6-mo of dietary energy restriction or exercise training on wholebody and hepatic fat oxidation of patients with nonalcoholic fatty liver disease(NAFLD).METHODS Participants were randomised into either circuit exercise training(EX;n = 13;3 h/wk without changes in dietary habits),or dietary energy restriction(ER) without changes in structured physical activity(ER;n = 8).Respiratory quotient(RQ) and whole-body fat oxidation rates(Fatox) were determined by indirect calorimetry under basal,insulin-stimulated and exercise conditions.Severity of disease and steatosis was determined by liver histology;hepatic Fatox was estimated from plasma β-hydroxybutyrate co.ncentrations;cardiorespiratory fitness was expressed as VO2 peak.Complete-case analysis was performed(EX:n = 10;ER:n = 6).RESULTS Hepatic steatosis and NAFLD activity score decreased with ER but not with EX.β-hydroxybutyrate concentrations increased significantly in response to ER(0.08 ± 0.02 mmol/L vs 0.12 ± 0.04 mmol/L,P = 0.03) but remained unchanged in response to EX(0.10 ± 0.03 mmol/L vs 0.11 ± 0.07 mmol/L,P = 0.39).Basal RQ decreased(P = 0.05) in response.to EX,while this change was not significant after ER(P = 0.38).VO_(2peak)(P 0.001) and maximal Fa_(tox) during aerobic exercise(P = 0.03) improved with EX but not with ER(P 0.05).The increase in β-hydroxybutyrate concentrations was correlated with the reduction in hepatic steatosis(r =-0.56,P = 0.04).CONCLUSION ER and EX lead to specific benefits on fat metabolism of patients with NAFLD.Increased hepatic Fat_(ox) in response to ER could be one mechanism through which the ER group achieved reduction in steatosis.     

Sex-specific association of BMI change with stroke in middle-aged and older adults with type 2 diabetes

Background and aimsWe aimed to evaluate the association between BMI change and stroke in middle-aged and older adults with type 2 diabetes and identify sex differences.Methods and resultsThe China Health and Retirement Longitudinal Study is an ongoing national population-based cohort study. Participants aged 45 or above with type 2 diabetes were enrolled and followed for stroke incidence. BMI change was defined as BMI at 2013-BMI at 2011. Of 1774 participants (mean [SD] age in 2011, 60.23 [8.88] years), 795 (44.8 %) were men. A total of 112 incident stroke cases were confirmed up to 2018. The incidence rate of stroke was similar between men and women (6.79 % vs 5.92 %, P = 0.516). BMI increase was independently associated with an increased stroke risk (adjusted odds ratio, 1.15; 95 % CI, 1.05–1.31) in men, while this positive association was not significant in women (adjusted odds ratio, 1.12; 95 % CI, 0.98–1.29). In addition, the positive dose–response relationship between BMI increase and stroke was observed only in men.ConclusionAmong middle-aged and older adults with type 2 diabetes, there is a sex-specific association of BMI change with stroke. An increase in BMI could result in a higher risk of incident stroke in men.     

Surgical outcomes and quality of life following exercise-based prehabilitation for hepato-pancreatico-biliary surgery: A systematic review and meta-analysis

BackgroundHepato-pancreatico-biliary (HPB) patients experience significant risk of preoperative frailty. Studies assessing preventative prehabilitation in HPB populations are limited. This systematic review and meta-analysis evaluates outcomes for HPB patients treated with exercise prehabilitation.Data sourcesA comprehensive search of MEDLINE (via Ovid), Embase (Ovid), Scopus, Web of Science Core Collection, Cochrane Library (Wiley), ProQuest Dissertations, Theses Global, and Google Scholar was conducted with review and extraction following PRISMA guidelines. Included studies evaluated more than 5 adult HPB patients undergoing ≥ 7-day exercise prehabilitation. The primary outcome was postoperative length of stay (LOS); secondary outcomes included complications, mortality, physical performance, and quality of life.ResultsWe evaluated 1778 titles and abstracts and selected 6 (randomized controlled trial, n = 3; prospective cohort, n = 1; retrospective cohort, n = 2) that included 957 patients. Of those, 536 patients (56.0%) underwent exercise prehabilitation and 421 (44.0%) received standard care. Patients in both groups were similar with regards to important demographic factors. Prehabilitation was associated with a 5.20-day LOS reduction (P = 0.03); when outliers were removed, LOS reduction decreased to 1.85 days and was non-statistically significant (P = 0.34). Postoperative complications (OR = 0.70; 95% CI: 0.39 to 1.26; P = 0.23), major complications (OR = 0.83; 95% CI: 0.60 to 1.14; P = 0.24), and mortality (OR = 0.67; 95% CI: 0.17 to 2.70; P = 0.57) were similar. Prehabilitation was associated with improved strength, cardiopulmonary function, quality of life, and alleviated sarcopenia.ConclusionsExercise prehabilitation may reduce LOS and morbidity following HPB surgery. Studies with well-defined exercise regimens are needed to optimize exercise prehabilitation outcomes.     

Using urinary metabolomics to identify metabolic pathways linked to cardiac structural alterations in young adults: The African-PREDICT study

Background and aimsRisk factor exposure from young ages was shown to contribute to cardiovascular events - cardiac hypertrophy, which may be accompanied by an altered metabolism. To determine how early metabolic alterations associate with myocardial structural changes, we profiled urinary metabolites in young adults with cardiovascular disease (CVD) risk factor(s) and a control group without CVD risk factors.Methods and resultsWe included healthy adults (N = 1202), aged 20–30 years, stratified based on risk factors, i.e., obesity, physical inactivity, elevated blood pressure (BP), hyperglycemia, dyslipidemia, low socio-economic status, smoking and excessive alcohol use - forming the CVD risk group (N = 1036) and the control group (N = 166). Relative wall thickness (RWT) and left ventricular mass index (LVMi) were measured using echocardiography. Targeted metabolomics data were obtained using a liquid chromatography-tandem mass spectrometry method. Clinic systolic BP, 24 h BP and RWT were higher in the CVD risk group compared to the control group (all P ≤ 0.031). Exclusively in the CVD risk group, RWT associated with creatine and dodecanoylcarnitine; while LVMi associated with glycine, serine, glutamine, threonine, alanine, citrulline, creatine, proline, pyroglutamic acid and glutamic acid (all P ≤ 0.040). Exclusively in the control group, LVMi associated with propionylcarnitine and butyrylcarnitine (all P ≤ 0.009).ConclusionIn young adults without CVD, but with CVD risk factors, LVMi and RWT associated with metabolites linked energy metabolism (shifting from solely fatty acid oxidation to glycolysis, with impaired creatine kinase activity) and oxidative stress. Our findings support early onset metabolic changes accompanying cardiac structural alterations due to lifestyle and behavioural risk factors.