Demers, K., Maastricht University Medical Center+, Maastricht, the Netherlands.
van Kuijk, S.M.J., Pierik, M.J., Jonkers, D., Stassen, L.P.S. & Bongers, B.C.

PLoS One 2026 Issue 10 Pages e0354707

PURPOSE: To develop predictive equations for oxygen uptake at peak exercise (VO2peak) measured during a cardiopulmonary exercise test (CPET) for patients with inflammatory bowel disease (IBD) using submaximal CPET-derived parameters and the steep ramp test, along with demographic and clinical characteristics.
METHODS: This study included patients with IBD in remission or with mild-to-moderate disease activity who performed a CPET and a steep ramp test within 14 days. Submaximal CPET-derived parameters included oxygen uptake (VO2) at the ventilatory anaerobic threshold (VAT) and oxygen uptake efficiency slope (OUES), while the outcome of the steep ramp test was the work rate achieved at peak exercise (WRpeak).
RESULTS: Predictive regression equations with submaximal VO2 at the VAT and with OUES, when combined with age and body fat percentage, explained >89% of the variance in VO2peak (optimism-adjusted R2 = 0.895 and 0.938). Predictive capacity increased when both VO2 at the VAT and OUES were combined in a predictive regression equation, together with age, body fat percentage, and clinically active disease (optimism-adjusted R2 = 0.951). Steep ramp test WRpeak explained 89% of the variance in VO2peak (optimism-adjusted R2 = 0.892).
CONCLUSION: The highly predictive equations developed in this study support the use of the submaximal CPET and the steep ramp test as alternatives for assessing VO2peak in patients with IBD in remission or with mild-to-moderate disease activity in clinical and research settings.

Patil, Pranoti R    Karad, INDIA.
Devi, Poovishnu T

Cureus [Cureus] 2026 Aug 29; Vol. 18 (8), pp. e115400. Date of Electronic Publication: 2026 Aug

Headings by Dr Older

Background Patients undergoing coronary artery bypass grafting (CABG) commonly experience reduced lower-limb strength, impaired balance, decreased functional mobility, and autonomic dysfunction during the postoperative period. These impairments may increase fall risk and limit daily activities. The Otago Exercise Program (OEP) is an evidence-based exercise intervention designed to improve lower-limb strength, balance, and functional performance, while resonance frequency breathing (RFB) has been shown to enhance cardiac autonomic regulation and heart rate variability (HRV). Although both interventions have demonstrated individual benefits, evidence regarding their combined application in phase II cardiac rehabilitation following CABG remains limited. Therefore, this study aimed to evaluate the effects of a combined OEP and RFB intervention on balance, lower-limb strength, functional mobility, and cardiac autonomic function in post-CABG patients.
Objective To evaluate the effects of a combined OEP and RFB intervention on balance, lower-limb strength, functional mobility, and cardiac autonomic regulation as evaluated via HRV in patients undergoing phase II cardiac rehabilitation following CABG.
Materials and methods A single-group pre-test and post-test experimental study was conducted among 40 post-CABG patients aged 40 to 60 years. The eight-week intervention combined supervised OEP multi-component exercises three times per week with daily home-based RFB paced precisely at six breaths per minute for 15 to 20 minutes. Lower extremity functional strength was evaluated by the 30-Second Chair Stand Test, and dynamic mobility was monitored with the Timed Up and Go (TUG) test. Static postural stability was evaluated using the Four-Stage Balance Test. Cardiac autonomic regulation was evaluated using short-term five-minute electrocardiographic (ECG) time-domain metrics, specifically tracked through the mean R-R interval and the root mean square of successive differences (RMSSD).
Results Improvements were observed following the intervention. The TUG test results improved from 17.95 ± 2.86 seconds to 14.68 ± 2.93 seconds (p < 0.001), indicating improvement in functional mobility. The lower limb strength also improved. The 30-Second Chair Stand Test scores went up from 13.03 ± 1.83 to 15.78 ± 2.03 repetitions (p < 0.001). We also saw improvements in balance, tandem stance, and single-leg stance (p < 0.0001). Autonomic function also improved, with an increase in RMSSD from 18.03 ± 2.59 ms to 21.96 ± 2.59 ms (p < 0.001); these findings suggest improved parasympathetic activity.
Conclusions The combined OEP and RFB intervention may support physical function, balance, functional mobility, and autonomic regulation in patients undergoing phase II cardiac rehabilitation after CABG surgery. The intervention appeared to be safe and useful in a home-based rehabilitation setting and may be a helpful approach in cardiac rehabilitation. However, the absence of a control group and separate OEP and RFB groups limits the ability to determine their individual or combined effects. Future studies with appropriate control and separate intervention groups are needed to confirm these findings.

Mainzer, Gur; Padeh Medical Center, Poriya, Israel.
Khourey, Faris;Zucker-Toledano, Merav;et al

European journal of applied physiology [Eur J Appl Physiol] 2026 Sep 28. Date of Electronic Publication: 2026 Sep 28.

• Purpose: To compare oxygen pulse (O₂P) responses during cardiopulmonary exercise testing (CPET) in healthy adults using two ergometers, Treadmill and Cycle ergometer, and to determine the prevalence of O₂P flattening and the modality-specific characteristics of O₂P curve dynamics.
• Methods: Thirty-four healthy adults (29.4 ± 6.9 years; 35% female) completed two maximal CPETs on both Cycle and Treadmill, in a random order within three weeks. O₂P flattening, defined as the absence of a further increase in O₂P despite increasing workload, was assessed visually and confirmed quantitatively.
• Results: Twelve participants (35%) demonstrated O₂P flattening or decline, nine (27%) exclusively during Treadmill testing. A significant group × modality interaction was observed for peak O₂P (p < 0.05), with lower values in participants with flattening than in those showing a continuous rise. (Cycle: 9.9 ± 3.2 vs. 13.6 ± 2.7 ml/min/beat; Treadmill: 11.8 ± 3.7 vs. 16.6 ± 3.7 ml/min/beat). In addition, an O₂ P of ≤ 12.8 ml/beat on the Cycle increased the likelihood of flattening during maximal Treadmill exercise by 7.5 times (OR 7.5, p = 0.03).
• Conclusion: O₂P flattening was more frequently observed during treadmill exercise, indicating that O₂P trajectories are exercise modality dependent. In individuals with low peak O₂P during cycle ergometry, additional assessment using treadmill CPET may offer complementary information.

Djassemi O; Department of Bioengineering,San Diego, USA
Chang AY; McGuire WC; Mitchell E;

ACS Sensors. 11(2):1413-1424, 2026 Feb 27. VI 1

management of sepsis, shock, and metabolic stress, yet current serum
assays remain invasive, intermittent, and resource-intensive. We present a
clinical evaluation of a minimally invasive microneedle-based
electrochemical biosensor for real-time interstitial fluid (ISF) lactate
monitoring. The microneedle biosensor features a platinum working
electrode modified with a lactate oxidase reagent layer and a polyvinyl
chloride anti-fouling membrane for H2O2-mediated amperometry, toward
highly selective and stable ISF lactate detection. In a pilot study of
twenty-one participants across an intensive care unit, emergency
department, cardiopulmonary exercise testing, and controlled laboratory
settings, two enzyme-based microneedle sensors placed on the forearm and
thigh continuously tracked lactate for 4 h. Sensor performance
demonstrated strong agreement with blood lactate assays (r = 0.94), high
diagnostic accuracy for hyperlactatemia (>4 mmol/L; receiver operating
characteristic analysis, area under the curve = 0.95), and minimal bias
(-0.028 mmol/L) over a wide dynamic range (0.7-22.9 mmol/L) with high
selectivity against interferents. No significant ISF-blood differences (p
> 0.05) or adverse events were observed. These findings establish
microneedle biosensors as a promising platform for precision medicine,
with considerable potential to transform sepsis care, guide resuscitation,
and improve assessment of exertional dyspnea.

Lin Y; Department of Ultrasound, Fujian Medical University, Longyan, China.
Hou S; Lin J; Zhang T et al

Cardiology. 151(4):458-470, 2026. VI 1

Introduction: This study aims to assess left ventricular (LV) function and
exercise endurance in patients with hypertrophic cardiomyopathy (HCM)
using a combination of left ventricular pressure-strain loop (LV-PSL) and
cardiopulmonary exercise testing (CPET) and to explore the correlation of
the maximum left ventricular wall thickness (MWT) with clinical,
echocardiographic, and CPET parameters.

METHODS: A total of 55 patients with nonobstructive HCM, diagnosed
between January 2022 and March 2023 at Longyan First Affiliated Hospital
of Fujian Medical University, were included, along with 55 healthy
volunteers as a control group. Two-dimensional ultrasound speckle tracking
technology was used to obtain global longitudinal strain (GLS),
longitudinal strain peak time dispersion (PSD), as well as the myocardial
global work index (GWI), myocardial global constructive work (GCW), global
wasted work (GWW), and global work efficiency (GWE). The differences in
these parameters were compared between the two groups before and after
CPET. CPET was used to measure peak oxygen consumption (Peak VO2),
anaerobic threshold (AT), ventilation equivalent for carbon dioxide slope
(VE/VCO2 slope), oxygen pulse (VO2/HR), and metabolic equivalents (METs),
and the differences between the two groups were also compared.

RESULTS: Compared to the control group, the HCM group showed significant
reductions in GLS, GWI, GCW, and GWE, while GWW and PSD were significantly
increased, with statistical significance (p < 0.05). Peak VO2, AT, VO2/HR,
and METs were significantly lower in the HCM group compared to the control
group, while VE/VCO2 slope did not show a significant increase (p > 0.05).
CPET, GWI, and GCW did not increase significantly in the HCM group (p >
0.05), whereas GWW and PSD showed significant increases (p < 0.05). In
contrast, in the control group, GWI and GCW increased significantly after
CPET (p < 0.05), and no significant changes were observed in GWW and PSD
(p > 0.05). Univariable linear regression analysis showed that MWT was
correlated with NYHA class, GLS, PSD, GCW, GWW, Peak VO2, and AT (p <
0.05). Multivariate linear regression analysis confirmed the independent
associations of MWT with PSD, GCW, and GWW (p < 0.05).

CONCLUSION: LV-PSL combined with CPET is effective in early detection of
LV function and exercise endurance impairment in HCM

Jacob KA; Department of Pediatric Cardiac Surgery, Utrecht, the Netherland
Korsuize NA; van Wijk A; Slieker MG; et al

Journal of Thoracic & Cardiovascular Surgery. 172(4):1074-1082.e2, 2026  Vol 1 Oct.

OBJECTIVES: Congenital critical aortic stenosis is frequently accompanied
by endocardial fibroelastosis (EFE), impairing diastolic compliance and
long-term ventricular performance. An early Ross procedure, with or
without concomitant EFE resection may restore left ventricular (LV)
function; however, long-term functional outcomes remain poorly
characterized. We evaluated long-term clinical and functional outcomes
after Ross procedure in neonates and infants with and without EFE.

METHODS: Patients who underwent a Ross operation at <1 year of age
between January 2005 and January 2025 were included. Demographic,
echocardiographic, and long-term clinical data were analyzed. Subgroup
assessment was performed in patients with the most pathologic LV, that is,
with EFE, and included cardiac magnetic resonance imaging and
cardiopulmonary exercise testing. The primary outcome was survival;
secondary outcomes included LV function, EFE recurrence, and exercise
capacity.

RESULTS: Thirty-six patients underwent the Ross procedure (median age, 55
days; interquartile range, 20-136), and 17 patients (47%) had EFE.
Operative mortality was 5.6% (2/36), with no late deaths during follow-up
(10 +/- 4 years). Late echocardiography demonstrated unobstructed LV
outflow and normalized LV function at follow-up. Ten patients with EFE,
after we obtained consent for additional diagnostic evaluation, had mostly
normalized LV function confirmed on cardiac magnetic resonance imaging
with no evidence of recurrent EFE. In these 10 patients, cardiopulmonary
exercise testing demonstrated predominantly normal aerobic capacity.

CONCLUSIONS: Biventricular repair in neonates and infants with critical
aortic stenosis is associated with excellent survival and substantial LV
recovery even in the presence of severe EFE.

Wang R; chool of Medicine South China University of Technology, Guangzhou, China.
Huang Z; Jiang Z; Bai B;et al

BMC Anesthesiology. 26(1), 2026 Jul 06. VI 1

BACKGROUND: In the PORT trial (Perioperative Rehabilitation in Patients
Undergoing Elective Cardiac Valve Surgery: A Randomised Controlled Trial),
a short-term multidomain perioperative rehabilitation programme was
associated with a reduced incidence of postoperative pneumonia in patients
undergoing elective cardiac valve surgery. Whether baseline peak oxygen
consumption (peak VO2), a marker of cardiorespiratory reserve, modifies
the effect of this intervention remains uncertain.

OBJECTIVES: To evaluate whether the association between perioperative
rehabilitation and postoperative outcomes differs according to baseline
peak VO2 (<= 20 vs. > 20 mL.kg-1.min-1).

METHODS: This exploratory subgroup analysis included 702 participants
from the PORT trial who underwent preoperative cardiopulmonary exercise
testing. Patients were stratified by baseline peak VO2 and randomized to
perioperative rehabilitation-comprising education, inspiratory muscle
training, active cycle of breathing techniques, and early mobilization-or
usual care. The primary endpoint was a composite of in-hospital all-cause
mortality, postoperative pulmonary complications (PPCs), and prolonged
hospitalization (> 7 days). Logistic and Cox regression models adjusted
for prespecified covariates were used to estimate treatment effects within
peak VO2 strata, and treatment-by-peak VO2 interactions were tested.

RESULTS: Of 702 participants, 202 (29%) had peak VO2 >20 and 500 (71%)
had peak VO2 <=20 mL.kg-1.min-1. The composite primary endpoint did not
differ significantly between rehabilitation and usual care in either
stratum (interaction P = 0.62). Perioperative rehabilitation was
associated with a lower incidence of postoperative pneumonia in both peak
VO2 >20 mL.kg-1.min-1 (adjusted OR 0.30; 95% CI 0.13-0.71) and <= 20
mL.kg-1.min-1 (adjusted OR 0.65; 95% CI 0.47-0.90), with no significant
interaction between peak VO2 category and treatment effect (P for
interaction = 0.12). No significant effect modification was observed for
other outcomes, including SICU stay, total hospitalization duration, or
3-month mortality.

CONCLUSIONS: In this exploratory analysis of the PORT trial, the
reduction in postoperative pneumonia associated with short-term
perioperative rehabilitation was consistent across strata of baseline peak
VO2. These findings suggest that the pneumonia benefit of
respiratory-focused perioperative rehabilitation may not depend on
baseline cardiorespiratory fitness, although adequately powered studies
are required to definitively assess effect modification. Although the
observed reduction in pneumonia was statistically significant and
biologically plausible, it arose from a secondary exploratory analysis
without adjustment for multiple comparisons and should therefore be
interpreted with caution.

Dueblin SW; Bern University Hospital, University of Bern,Switzerland
Wuethrich PY; Engel D; Eser P; et al

BMC Geriatrics. 26(1), 2026 Jul 07. VI 1

BACKGROUND: Older adults awaiting major surgery often present with reduced
physical fitness and respiratory muscle weakness, which are associated
with increased postoperative complications. Prehabilitation may improve
functional capacity, but evidence for its effect on inspiratory muscle
strength in high-risk older adults remains limited. The main objective was
to assess the change in maximal inspiratory pressure (MIP) in the
preoperative period in high-risk patients receiving home-based
tele-supervised prehabilitation compared to standard care.

METHODS: This exploratory analysis included a subset of secondary outcome
data from a prospective, two-arm, parallel-group randomised controlled
trial conducted at a single university hospital in Switzerland. Patients
aged >= 65 years awaiting elective cardiac or major non-cardiac surgery
with a proven fitness deficit measured by cardiopulmonary exercise testing
(CPET) were included. Participants randomized in the intervention arm
received a multimodal, home-based tele-supervised prehabilitation
programme over 2-4 weeks addressing deficits in physical fitness,
nutrition, and anaemia, while controls received standard preoperative
care.

RESULTS: Eighty eight participants were analysed (intervention n = 48;
control n = 40). Patients in the intervention group showed improvement in
MIP after the training period, whereas the control group demonstrated a
decline (median change + 10.5 [0.00; 16.2] vs. – 3.00 [-8.00; 1.50] cmH2O;

CONCLUSIONS: Home-based tele-supervised IMT, delivered as part of a
multimodal prehabilitation programme, improved maximal inspiratory
pressure over the preoperative period in elderly high-risk surgical
patients. The observed MIP decline in the control group suggests that the
preoperative waiting period itself may carry a risk of functional
deterioration in this population. Whether MIP improvements translate into
reduced postoperative morbidity will be addressed by the primary outcome
of the ongoing PREHABIL trial.