CONTEXT:Primary hyperparathyroidism (PHPT) is often caused by a parathyroid adenoma (PTA). Subtraction scintigraphy with 123I and 99mTc -MIBI SPECT-CT, and neck ultrasound examination as a hybrid scan (HS) can be used to localize the PTA in order to promote minimally invasive surgery. OBJECTIVE:This study evaluated patients referred for HS, the ability of the HS to correctly localize PTA(s), as well as the diagnostic performance of HS. METHODS:Data was retrospectively analyzed for 300 patients with PHPT referred for HS from 2019 to 2023 in a single-centre hospital. We used Begg and Greenes' correction method to calculate diagnostic accuracy, as well as calculated percentage of adenoma(s) correctly localized per patient who underwent PTX or bilateral neck exploration (BNE). RESULTS:In 282 patients with PHPT undergoing HS for PTA localization, the HS was positive in 71%. Only 65% of these patients were referred to PTX. Using correction methods, we found a sensitivity and specificity of the HS of 73% and 78%, respectively. The positive predictive value was 99%, while the negative predictive value was 9%. The HS correctly localized PTA in 90% of the patients. Scintigraphy correctly localized 86% of the PTAs, SPECT-CT 85%, and ultrasound 76%. CONCLUSION:A positive HS was very likely to localize the PTA correctly, whereas a negative HS had limited diagnostic value. Surprisingly, a large proportion of patients undergoing HS were never considered for surgery, resulting in partial reference bias in the evaluation of the diagnostic accuracy.
A reduction of intrathoracic pressure during the Mueller manoeuvre (MM) has been shown to decrease left ventricular (LV) forward stroke volume in patients with systolic heart failure. To assess the underlying mechanisms, we analyzed MM-induced changes in LV inflow and outflow dynamics in 13 healthy individuals (mean age 42 y, 8 men) and in 13 patients with dilated cardiomyopathy (DCM) (mean age 44 y, 8 men) having LV ejection fraction <40% without mitral regurgitation. The subjects performed MM with a target of -30 mmHg pressure for >10 s. Doppler echocardiography was used to record systolic and diastolic flow velocities at the aortic and mitral valve annulus, respectively, during quiet respiration and the MM. The respective flow velocity-time integrals (VTI) were measured. Compared with control subjects, patients with DCM had a larger MM-induced decrease in the aortic VTI (-4.2 ± 0.3 vs. -1.6 ± 0.5 cm; p < 0.001) combined with a tendency to a smaller decrease in the mitral VTI (-1.4 ± 0.5 vs. -2.2 ± 0.3 cm; p = 0.070). The mitral-to-aortic VTI ratio, an indirect mitral regurgitant index, increased in DCM from 0.78 ± 0.04 to 1.03 ± 0.08 (p = 0.006) but decreased in the control group from 0.70 ± 0.03 to 0.61 ± 0.03 (p = 0.025). The group x MM interaction was statistically highly significant (F = 16.8, p < 0.001). We conclude that, in DCM-related heart failure, a reduction of intrathoracic pressure during the MM increases the mitral-to-aortic VTI ratio suggesting appearance of functional mitral regurgitation.
BACKGROUND:The calculation of the left atrioventricular coupling index (LACI) by the ratio between left atrial (LA) and left ventricular (LV) end-diastolic volumes reflects the close interaction between LA and LV. AIM OF THE STUDY:The study aimed to assess LACI using echocardiography before and after percutaneous coronary intervention (PCI) compared with LV ejection fraction (LV-EF) in acute coronary syndrome (ACS). SUBJECTS AND METHODS:This retrospective cohort analysis included 193 ACS patients (65.1 ± 12.5 years, 71.6% males), who underwent PCI. Both LACI and LV-EF were calculated before and after PCI. RESULTS:At presentation, 156 (80.8%) patients had LV-EF reduction; mild in 61 (39.1%), moderate in 77 (49.3%) and severe in 18 (11.5%). Using LACI < 25% as the cutoff value for normal, 40 (20.7%) patients had impaired LACI. Out of the 153 patients with normal LACI, 127 (83%) had reduced LV-EF. Patients were classified into three groups: I: 51 (26.4%) with STEMI, II: 82 (42.5%) with NSTEMI and III: 60 (31.1%) with unstable angina. Baseline LV-EF and LACI did not show significant differences between the three groups. Over a 12.8 ± 8.2 month follow-up post PCI, LV-EF improved in 68 (43.6%) out of 156 patients becoming normal in 28 (17.9%), mildly reduced in 65 (41.7%), moderately reduced in 55 (35.2%) and severely reduced in 8 (5.1%). Post PCI, LACI normalized in 19 (47.5%) out of 40 patients with impaired baseline LACI. CONCLUSION:Assessing LACI in ACS provided a better understanding of LA and LV dynamics and its reduction following PCI indicates a better prognosis.
BACKGROUND:Leg discomfort, assessed with the Borg category-ratio 0-10 (Borg CR10) scale, is a primary reason for exercise cessation in both health and disease. However, interpretation during cardiopulmonary exercise testing (CPET) is limited by the absence of normative reference equations. PURPOSE:Develop normative reference equations for leg discomfort during CPET in relation to absolute and relative power output (W) and rate of oxygen uptake (V'O2). METHODS:This was a retrospective analysis of the Canadian Cohort Obstructive Lung Disease (CanCOLD) study. We included healthy males and females aged ≥40 years who completed symptom limited incremental cycle CPET. The probability of each Borg CR10 leg discomfort rating by W or V'O2 was predicted using multinomial logistic regression. Model performance was evaluated by fit, calibration, discrimination (c-statistic), and externally validated in an independent sample (n = 86) of healthy Canadian adults. RESULTS:In total, 156 participants (43% female) were included (mean age 64.8 years). The models demonstrated good discrimination in both internal and external validation (AUC 0.85-0.90), with similar performance across absolute and relative W and V'O2. An upper limit of normal ([ULN]; 95th percentile) could not be defined, as leg discomfort responses were highly clustered within the predicted normal range across exercise intensities. CONCLUSIONS:We present normative reference equations for leg discomfort during CPET. Although an ULN could not be established, these models enable grading and interpretation of leg discomfort relative to the predicted normal responses and facilitate comparisons across individuals and groups in both clinical and research settings.
AIMS:Heart transplant (HTx) patients are known to be at risk of coronary microvascular dysfunction as well as having decreased exercise capacity. The aim of this study was to investigate if microvascular function in HTx patients differs from healthy controls and is related to objective measures of exercise capacity. METHODS AND RESULTS:Twenty-nine HTx patients (51 ± 15 years, 34% women) and 26 healthy controls (57 ± 10 years, 38% women) underwent CMR. Quantitative myocardial perfusion maps were acquired using single-bolus (0.05 mmol/kg), dual-sequence perfusion mapping at adenosine stress and at rest. In addition, all HTx patients performed a maximal cardiopulmonary exercise test with gas-exchange analysis for objective assessment of exercise capacity. Heart transplant patients had lower stress myocardial perfusion (2.9 ± 0.8 vs 3.4 ± 0.8, p = 0.03) and lower myocardial perfusion reserve (MPR) (2.7 ± 0.7 vs 3.8 ± 1.2, p < 0.001) compared to healthy controls. Furthermore, MPR in HTx patients was correlated with maximal workload (R2 = 0.25, p = 0.016), O2 pulse (R2 = 0.21, p = 0.026), peak O2 consumption (VO2 peak) (R2 = 0.25, p = 0.015) and O2 consumption (VO2) at the anaerobic threshold (AT) (R2 = 0.27, p = 0.011). CONCLUSION:Microvascular function as assessed by quantitative CMR perfusion mapping is lower in HTx patients than in healthy controls and is partly related to objective measures of exercise capacity.
OBJECTIVES:Chronic obstructive pulmonary disease (COPD) is associated with impaired peripheral muscle oxygenation and reduced exercise tolerance. In our study, we planned to use near-infrared spectroscopy (NIRS) to measure muscle oxygenation dynamics during exercise in patients with COPD, active smokers and healthy individuals. METHODS:This prospective study included 50 stable COPD patients, 30 current smokers without COPD and 20 healthy controls. Clinical measures and pulmonary function were assessed, while muscle oxygenation was continuously monitored by NIRS during the 6-min walk test (6MWT) to derive T½ recovery time, reoxygenation rate and functional exercise performance. RESULTS:COPD patients had significantly lower muscle oxygen saturation (SmO2) at baseline, end-6MWT and 5 min post-test than controls (p < 0.001). COPD patients had the longest T½ recovery time (p = 0.03), and their reoxygenation rate was similar to that of active smokers but shorter than that of the healthy control group (p < 0.001). Active smokers had lower SmO2 and reoxygenation rates before and after exercise than the control group (p < 0.05). In COPD patients, the greater the difference in oxygen saturation (SpO2) levels before and after 6MWT, and the lower the haemoglobin level, the longer the T½ recovery time (p < 0.05). The 6MWT interval was longer in those with high SpO2 and SmO2 levels before and after 6MWT, shorter T½ recovery times and high haemoglobin levels (p < 0.05). CONCLUSION:COPD and smoking significantly impair post-exercise muscle oxygenation recovery, suggesting that peripheral microvascular dysfunction contributes to reduced functional exercise performance beyond pulmonary limitation.
OBJECTIVE:This study aimed to evaluate and validate the utility of a conventional ultrasound-based carotid grading system in assessing disease activity in Takayasu arteritis (TA) with carotid artery involvement, distinguishing between active and inactive patients, and monitoring therapeutic response. METHODS:The 108 patients were classified into the clinically-active group (CAG) and the clinically-inactive group (CIG), and were further classified into Grades I-V according to carotid ultrasound imaging characteristics, with Grades I, II, and V categorized as the ultrasound-active group (UAG), and Grades III and IV as the ultrasound-inactive group (UIG). Intergroup differences were compared, and the diagnostic performance of the ultrasound grading system for disease activity was evaluated by the ROC curve analysis. Treatment response assessed in 68 follow-up patients based on ultrasound grading. RESULTS:The CAG exhibited higher inflammatory markers and greater carotid wall thickness (p < 0.05). Grades I, II, and V predominated in the CAG, whereas Grades III and IV were more frequent in the CIG. Compared to the UIG, the UAG showed significantly elevated ESR, CRP, C3, and IgM, and thicker carotid walls (p < 0.05). The ultrasound grading system achieved an AUC of 0.710 for identifying clinical activity in TA. Combined with carotid wall thickness, diagnostic performance surpassed either parameter alone. Among 68 follow-up patients, the UAG had higher inflammatory markers and greater wall thickness at baseline but demonstrated more pronounced improvement in disease activity after treatment. CONCLUSIONS:Conventional ultrasound is a reliable tool for characterizing vascular wall inflammation and monitoring therapeutic response in TA patients with carotid artery involvement.
BACKGROUND:Obstructive sleep apnea (OSA) is linked to arrhythmia and cardiovascular morbidity, but the cardiac response to individual obstructive events is incompletely characterised at minute-scale resolution. We aimed to determine whether ECG-derived autonomic features distinguish apnea from nonapnea minutes and whether these features change before scored event onset. METHODS:We performed a secondary analysis of the PhysioNet Apnea-ECG learning set (34 subjects after exclusion of one duplicated recording; 30 male, 4 female; mean age 47.0 ± 9.7 years; AHI 0-82.4 events/h). For each 1-min segment, we computed mean heart rate, SDNN, RMSSD, pNN50 and RR irregularity rate from QRS-derived RR intervals. Minutes were classified as baseline, preapnea, apnea, or post-apnea and associations tested using mixed-effects regression with subject random intercepts. RESULTS:The analytic dataset comprised 17,004 min; 38.2% were apnea minutes. Apnea minutes showed a heart rate reduction of -2.66 bpm (95% CI: -2.92 to -2.41, p < 0.001) and an RMSSD increase of +19 ms (95% CI: 15-23, p < 0.001) versus baseline. In multivariable modelling, SDNN was the dominant feature (β = +0.472); RMSSD showed a sign reversal (β = -0.416) and reciprocal logistic odds ratios (SDNN OR 134.9 vs. RMSSD OR 0.034) consistent with substantial collinearity. Preapnea minutes showed directionally similar but smaller changes; post-apnea minutes showed partial normalisation. CONCLUSION:Obstructive apnea is associated with a reproducible minute-level autonomic signature of bradycardia and increased RR variability, with detectable shifts preceding scored event onset. Variability metrics, particularly SDNN, contribute more than mean heart rate. Findings require validation in cohorts with linked cardiovascular outcomes.
BACKGROUND:Gas-exchange derived pulmonary capacitance (GXCAP) is a non-invasive index of pulmonary arterial capacitance obtainable from submaximal cardiopulmonary exercise testing (CPET), but reference intervals in older adults, a key target population, are lacking. METHODS:A secondary analysis of an open-label clinical device trial, including 207 adults ≥ 60 years undergoing elective non-cardiac surgery was performed. Submaximal CPET with the Shape II system provided peak GXCAP, GXCAP-time slope, and GXCAP-VO2 slope. Sex-specific empirical 95% reference intervals (2.5th-97.5th percentiles) and indirect reference intervals were calculated using the refineR algorithm, which models the latent healthy subpopulation within routine data. Associations with age and sex were examined using correlation and group comparisons. RESULTS:The analytic cohort comprised 207 nonsmoking participants (119 males, 88 females). Males demonstrated higher peak GXCAP and steeper GXCAP-time and GXCAP-VO2 slopes than females. Age was modestly and inversely associated with peak GXCAP and GXCAP-time slope. Empirical reference intervals were wide and right-skewed, whereas refineR produced narrower, physiologically plausible intervals, for example, peak GXCAP 144.9-810.0 mL.mmHg (overall), with higher upper limits in males. CONCLUSIONS:In older adults undergoing preoperative evaluation, GXCAP metrics show clear sex differences. Indirect, refineR-based, reference intervals provide stable, clinically interpretable ranges that may enhance the use of GXCAP for noninvasively assessing pulmonary arterial capacitance in submaximal CPET. GXCAP derivatives (GXCAP-time slope and GXCAP-VO2 slope were introduced and may offer distinct advantages in submaximal cardiopulmonary exercise testing. CLINICAL TRIAL REGISTRATION:NCT05743673, Principal Investigator: Zyad J. Carr, M.D.
OBJECTIVES:Resistance exercise enhances executive function (EF) more effectively at moderate or higher intensities than at low intensity resistance exercise (LRE), probably with increased neural activity and lactate production to meet brain energy demands. Given that LRE remains widely applicable with less perceived exertion, and electrical muscle stimulation (EMS) increases lactate production and neural activation, we investigated whether combining LRE with EMS (LRE-EMS) effectively enhances EF, without increasing perceived exertion. DESIGN:A crossover randomized study. METHODS:Seventeen young men participated in a crossover randomized study to assess the cognitive effects of LRE alone, EMS alone, and LRE-EMS. The LRE protocol involved knee extensions at 40% one-repetition maximum for 4 sets of 10 repetitions. During the EMS condition, the participants remained seated for 260 s to match the duration of the other conditions, with EMS applied to the lower limb muscles. Subjective perceptions of exertion and fatigue during exercise were recorded. RESULTS:IC and lactate were measured at baseline, immediately postexercise, and 15 min postexercise. The LRE condition did not significantly increase IC (p = 0.100), whereas LRE-EMS resulted in significant IC improvements immediately and 15 min postexercise (both p < 0.001), with greater lactate increases compared to LRE and EMS. EMS demonstrated significant IC improvement at 15 min postexercise (p = 0.022). CONCLUSIONS:Perceived exertion and fatigue were greater with LRE-EMS compared with LRE and EMS. These findings suggest that LRE combined with EMS and EMS alone are effective strategies for cognitive improvement, but increased perceived exertion still exists.
There are few reliable predictors for reduced pain after biliary sphincterotomy or medical therapy in patients with sphincter of Oddi dysfunction (SOD). We explored whether prolonged intestinal bile excretion time, dilated common bile duct (CBD) diameter, or elevated alanine aminotransferase (ALT) were associated with reduced pain after treatment for SOD. This is a retrospective, single-centre study. Consecutive patients suspected of SOD were identified and screened. Medical treatment for SOD followed institutional standards in line with the Regional pain medication guidelines. The primary outcome was potential prognostic markers for reduced pain. In the biliary sphincterotomy group (n = 34), 85% patients experienced reduced pain when evaluated in the outpatient clinic, while 60% of patients receiving medical therapy (n = 159) experienced reduced pain (p = 0.009). No association was found between the hepatobiliary scintigraphy excretion time nor ALT and reduced pain in either treatment group. However, a dilated CBD was associated with reduced pain (odds ratio 2.89; 95% CI [1.02;8.17]). In SOD patients, amelioration of pain in both medically and surgically treated patients is primarily associated with common bile duct dilation, rather than hepatobiliary scintigraphy excretion time or ALT.
AIMS:Patients with myocardial infarction with non-obstructive coronary arteries (MINOCA) may be affected by coronary microvascular dysfunction with reduced stress perfusion. Changes in native T1 and T2 reflect changes in myocardial perfusion; therefore, the aim of our study was to investigate whether non-contrast, adenosine stress native T1 and T2 are affected in patients with previous suspected MINOCA. METHODS AND RESULTS:Patients with MINOCA and a normal CMR (n = 15, 59 ± 7 years, 60% female) underwent 1.5T CMR together with age- and sex-matched volunteers. The protocol included native T1, native T2 and quantitative perfusion mapping, at rest and during adenosine stress. Myocardial stress perfusion was globally reduced, both transmurally (2.9 ± 0.9 vs. 3.6 ± 0.7 mL/min/g, p = 0.02) and in the subendocardium (2.64 ± 0.81 vs. 3.47 ± 0.78 ml/min/g, p = 0.008) in patients with MINOCA, with a reduced global ratio of subendocardial-to-transmural stress perfusion (0.921 ± 0.042 vs 0.957 ± 0.039, p = 0.021). However, there were no differences in global transmural rest native T1 or T2, stress native T1 or T2, or ΔT1- or ΔT2 values between patients and volunteers. Overall, transmural myocardial perfusion correlated with native T1 (R2 = 0.27, p < 0.001) and T2 (R2 = 0.48, p < 0.001) globally, and ΔT1 correlated with the MPR globally (R2 = 0.15, p < 0.05). CONCLUSIONS:Native T1- and T2-mapping during adenosine stress, although correlated with quantitative myocardial perfusion, are not alone sufficiently sensitive methods for distinguishing patients with MINOCA and reduced stress perfusion from healthy volunteers.
BACKGROUND:Assessing functional capacity is a key aspect of exercise testing and offers important insights into health in adult populations. However, accurate assessment often requires laboratory-based maximal tests. This pilot study investigated whether a field-based self-paced submaximal stair ascent test could feasibly assess aerobic capacity and lower-limb strength in middle-aged and older adults. METHODS:Twenty-eight participants (20 women, 8 men) aged 40 to 70 years completed maximal treadmill and isometric leg press tests to assess maximal oxygen consumption (VO2max) and lower-limb strength, respectively. Participants also performed two separate self-paced stair ascents of four and six flights. Ascent time, mean vertical power, as well as rate of perceived exertion, absolute heart rate, and relative heart rate following the test were recorded. RESULTS:Ascent time and mean vertical power were associated with VO2max and lower-limb strength, with standardized regression coefficients ranging from -0.61 to -0.27 and from 0.41 to 0.73, respectively. However, these associations were attenuated and no longer statistically significant after controlling for age and sex. Predictive models based on the two best-performing stair ascent predictors selected by LASSO regression showed weak-to-moderate ability to predict VO2max (R2 = 0.21-0.52) with cross-validated model performance significantly different from zero. In contrast, the models did not significantly predict lower-limb strength. CONCLUSIONS:These preliminary findings suggest that a brief self-paced stair ascent test may offer a feasible field-based approach for estimating aerobic capacity in middle-aged and older adults. However, its predictive accuracy appears limited and should be further examined in larger samples.
OBJECTIVE:This exploratory study investigated associations between infrared thermography-derived skin temperatures in shoulder muscles and pain sensitivity, sleep quality, function, and quality of life in individuals with unilateral rotator cuff injuries. METHODS:In this cross-sectional study, 85 participants (53 females, 32 males) with rotator cuff injuries underwent thermographic imaging of the trapezius, deltoid, biceps, brachioradialis, supraspinatus, and subscapularis muscles. Outcomes included Pressure Pain Threshold (PPT), Visual Analogue Scale (VAS) pain scores, Pittsburgh Sleep Quality Index (PSQI) scores, Disabilities of the Arm, Shoulder, and Hand (DASH) scores, and Short Form-36 (SF-36) subdomains. Correlations were analysed using Pearson or Spearman tests. RESULTS:Skin temperatures of the trapezius and deltoid muscles showed positive correlations with PPT (rho = 0.235-0.422, p < 0.05) and negative correlations with DASH scores (rho = -0.228 to -0.233, p < 0.05). Temperatures of the deltoid, biceps, brachioradialis, and subscapularis correlated negatively with activity-related pain (rho = -0.234 to -0.301, p < 0.05). Biceps and brachioradialis temperatures were negatively correlated with PSQI scores (rho = -0.215 to -0.269, p < 0.05). Subscapularis temperature correlated positively with SF-36 subdomains, including Physical Role (rho = 0.308, p = 0.004) and General Health (rho = 0.276, p = 0.011). No significant correlations were observed for supraspinatus temperature or pain at rest/night. CONCLUSION:This analysis suggests that infrared thermography reveals muscle-specific thermal patterns associated with clinical outcomes in rotator cuff injuries, supporting its potential as a non-invasive diagnostic tool for personalised assessment and management. These preliminary findings warrant confirmation in future hypothesis-driven studies.
BACKGROUND:Exercise transcutaneous oximetry (Ex-TcPO2), through the minimal value of the "decrease from rest of oxygen pressure" (DROPmin), identifies ischemia during exercise in patients with PAD. However, its diagnostic performance at the thigh level compared to imaging modalities, has not been evaluated. The objective of this retrospective study was to perform an external validation of Ex-TcPO₂ results at the buttock and calf, a first validation of Ex-TcPO₂ at the thigh level and to determine the respective diagnostic performance of the DROPmin and DROPend (the DROP at the time of exercise cessation). METHODS:We studied 192 patients complaining of intermittent claudication. We retrieved DROPmin and DROPend values from Ex-TcPO2 testing and the presence/absence of an ipsilateral significant stenosis ( ≥ 70%) at imaging. RESULTS:The performance of Ex-TcPO₂ using DROPmin values at the buttock, thigh and calf levels were respectively fair (AUC = 0.70; 95% CI: 0.64-0.76), fair (AUC = 0.77; 95% CI: 0.72-0.83) and excellent (AUC = 0.93; 95% CI: 0.90-0.96). When using DROPend, the performance of Ex-TcPO2 was no more significant. DISCUSSION/CONCLUSION:This study showed that Ex-TcPO₂ has a fair to excellent accuracy for detecting the presence of at least one artery stenosis ≥70% in the lower limb according to buttock, thigh and calf area in highly selected patients. This study also highlights the importance of using the minimal value of DROPmin rather than the DROPend.
Food intake induces metabolic and hemodynamic changes, but its impact on many circulating protein biomarkers remains unclear. This study assessed the effect of a standardised meal on 85 plasma biomarkers measured by the Proseek Multiplex Metabolism panel. Twenty-two healthy adults (11 men, 11 women; mean age 25.9 ± 4.2 years) were examined after an overnight fast and at 30 and 120 min following a standardised meal. Plasma samples were analysed with the Proseek Multiplex Metabolism panel. Twelve biomarkers decreased significantly after food intake; none increased. Eight biomarkers were reduced at 30 min, and four remained decreased at 120 min. The largest changes (>20%) were observed for DNA-(apurinic/apyrimidinic site) endonuclease, eosinophil cationic protein, thyrotropin subunit beta, carbonic anhydrase 13, and Crk-like protein. Food intake has modest effects on most biomarkers in the Proseek Multiplex Metabolism panel, suggesting fasting may not be critical for routine use. However, caution is warranted for biomarkers showing >20% change. Further studies in diverse populations and disease states are needed to confirm these findings.
BACKGROUND:Peak expiratory flow (PEF) obtained from dedicated PEF meters and various types of spirometers is often used interchangeably in research, despite differences in both devices and expiratory maneuver technique. The aim of this study was to assess the effects of expiratory maneuver type and measurement device on PEF. METHODS:We recruited 20 healthy adults experienced in performing spirometry. Each subject performed three measurements using two expiratory maneuvers (a short, explosive maneuver and a long, spirometry-style maneuver) with four devices: the handheld microspirometers Medikro Duo and MIR Spirobank, the laboratory spirometer Vyntus Pneumo, and the Mini-Wright PEF meter. RESULTS:PEF differed significantly between devices (F(3,133) = 171.8, p < 0.001), but not between short and long expiratory maneuver techniques (F(1,133) = 2.24, p = 0.137). There was no significant interaction between device and technique (F(3,133) = 0.72, p = 0.543). Compared with the Mini-Wright, Spirobank yielded PEF values that were on average 87.1 L/min higher (74.6-99.7, p < 0.001), and Vyntus Pneumo 26.5 L/min higher (14.0-39.1, p < 0.001), whereas Medikro did not differ significantly from the Mini-Wright (mean difference -9.5 L/min, -22.1-3.1, p = 0.269). The pairwise differences between the three spirometers were all statistically significant (all p < 0.001). CONCLUSIONS:Because short and long expiratory maneuver techniques yield similar results on PEF, future studies of home spirometry may compare the diagnostic performance of PEF and forced expiratory volume in 1 s (FEV1) using the same long, spirometry-style expiratory maneuvers. However, comparison of absolute PEF values between devices must be done cautiously.
OBJECTIVES:Aortic stiffness increases ventricular afterload and limits exercise capacity in heart failure (HF), but its dynamic response to exercise remains insufficiently defined. This study aimed to evaluate exercise-induced changes in aortic stiffness and their association with functional capacity in patients with early-stage HF. Heart-rate recovery (HRR) was assessed as secondary parameter. METHODS:This prospective study enrolled 42 compensated HF patients (ejection fraction <45%) in sinus rhythm. Aortic diameters were measured 3 cm above the aortic valve using M-mode echocardiography to calculate the Stiffness Index (SI), Peterson's Elastic Modulus (Ep), and Aortic Distensibility (D). All patients underwent a symptom-limited treadmill test using the modified Bruce protocol. HRR was defined as the difference between peak heart rate and heart rate at 1 min of recovery. Echocardiographic measurements were repeated within 60 s after exercise. RESULTS:Aortic stiffness increased significantly after exercise [SI: 5.05 (4.18-6.30) to 6.03 (4.59-7.79); p < 0.001], while distensibility decreased [2.64 to 1.90 ×10 - 6 cm2·dyn-1; p < 0.001]. Patients with NYHA class II had higher SI and Ep and lower D at rest and post- exercise than NYHA class I patients (all p < 0.001). NYHA class was the only independent predictor of post-exercise stiffness (β = 3.32; 95% CI 1.33-5.30; p = 0.002). Exercise capacity was significantly lower in NYHA II patients (7.0 vs 10.1 METs; p < 0.001). HRR showed no significant association with aortic stiffness or exercise capacity. CONCLUSIONS:In early-stage HF, increased resting and exercise-induced aortic stiffness is strongly associated with reduced functional capacity, indicating early impairment of vascular compliance reserve during physiological stress.
OBJECTIVES:The primary objective of this study was to examine the association between the skeletal muscle mass-to-visceral fat area ratio (SVR) and cardiovascular disease (CVD) prevalence. METHODS:This study employed data from the 2011-2018 National Health and Nutrition Examination Survey (NHANES) to derive the SVR using dual-energy X-ray absorptiometry (DXA) measurements. CVD status was ascertained using self-reported physician-diagnosed medical history. Subsequent multivariable logistic regression analyses were performed to examine the relationship between SVR and CVD prevalence. Restricted cubic spline regression was utilized to examine underlying non-linear associations between the SVR and CVD risk. Stratified subgroup analyses were ultimately performed to assess the robustness of the findings. Sensitivity analyses were conducted with additional adjustment for total body fat percentage, and sex-stratified restricted cubic spline analyses were also conducted to explore potential differences in nonlinear associations between men and women. RESULTS:This study included 9383 participants, among whom 348 were diagnosed with CVD. Multivariable logistic regression models demonstrated a statistically significant inverse relationship between SVR and CVD prevalence (OR = 0.093; 95% CI: 0.016-0.542; p = 0.011). The association persisted after adjustment for total body fat percentage. RCS analysis revealed a non-linear association between the SVR and CVD risk. Moreover, subgroup analyses confirmed that the protective effect of SVR remained consistent across various baseline characteristics. CONCLUSION:The findings indicate that lower SVR correlates with an elevated risk of CVD, and this association has been robustly demonstrated across multiple studies.
AIMS:Patients with Fontan circulation have reduced functional capacity, due to a reduced cardiac output, but also to an abnormal lung function and respiratory muscle weakness. This study aimed to assess lung function and exercise capacity in a cohort of patients with Fontan circulation and evaluate the prognostic impact of restrictive lung function (RLF). In addition, diaphragmatic ultrasound (DUS) investigated diaphragmatic function in a subgroup of patients. METHODS:Patients with Fontan palliation who underwent lung function evaluation were included. A subgroup of patients additionally underwent DUS to assess diaphragmatic function. RESULTS:The study population consisted of 53 post-Fontan patients (mean age 25 ± 10 years). Exercise capacity was reduced, with a median peak VO₂ of 18.4 mL/kg/min (IQR 14.7-22.6). Oxygen pulse was reduced and flattened, and ventilatory efficiency was impaired (mean VE/VCO₂ slope 36 ± 7), without evidence of mechanical ventilatory limitation. Spirometry revealed RLF in 48% of patients. RLF was associated with lower peripheral oxygen saturation, diuretic therapy use, and lower engagement in regular physical activity. Moreover, RLF was significantly associated with adverse events at follow-up (χ²: 6.8, p = 0.004). Diaphragm ultrasound (DUS), performed in 10 patients, showed abnormal function of at least one hemidiaphragm in most cases. CONCLUSIONS:Patients with Fontan circulation exhibit a markedly reduced exercise functional capacity resulting from a complex interplay between cardiac, pulmonary, and peripheral factors. Restrictive lung function was associated with increased need for diuretic therapy and lower levels of physical activity. Abnormal diaphragmatic function was frequently observed and may represent a potentially modifiable contributor to functional limitation warranting further investigation.
