Smarz K; Jaxa-Chamiec T; Zaborska B; Tysarowski M; Budaj A;

Original Publication: San Francisco, CA : Public Library of Science
[This corrects the article DOI: 10.1371/journal.pone.0255682.].

Baidats Y; Public Health and Sport Sciences, Medical School, University of Exeter, Exeter, UNITED KINGDOM. & Israel
Kadosh S; Jones AM; Wilkerson D; Velner A;Reuveny R;Segel MJ;

Medicine and science in sports and exercise [Med Sci Sports Exerc] 2024 Jul 11.
Date of Electronic Publication: 2024 Jul 11.

Purpose: We studied the effect of O2 supplementation on physiological response to exercise in patients with moderate to severe interstitial lung disease (ILD).
Methods: 13 patients (age 66 ± 10 yrs., 7 males) with ILD (TLC 71 ± 22% predicted, carbon monoxide diffusion capacity (DLCO) 44 ± 16% predicted) and 13 healthy individuals (age 50 ± 17 yrs., 7 males) were tested. ILD patients performed symptom-limited cardiopulmonary exercise tests and constant work-rate tests (CWRTs) at 80% of the work-rate (WR) at the gas exchange threshold (GET). Tests breathing room air (RA, 21% O2) were compared to tests performed breathing 30% O2. Oxygen-uptake (V̇O2) kinetics were calculated from the CWRT results.
Results: In the ILD group, peak WR, peak V̇O2 and V̇O2 at the GET improved significantly when breathing 30% O2 compared to RA (mean ± SD 66 ± 23 vs 75 ± 26 watts, 15 ± 2 vs 17 ± 4 ml/kg/min and 854 ± 232 vs 932 ± 245 ml/min; p = 0.004, p = 0.001 and p = 0.01, respectively). O2 saturation (SPO2%) at peak exercise was higher with 30% O2 (97 ± 4% vs 88 ± 9%, p = 0.002). The time constant (tau) of V̇O2 kinetics was faster in ILD patients while breathing 30% O2 (41 ± 10 sec) compared to RA (52 ± 14 sec, p = 0.003). There was a negative linear relation between tau and SPO2% with RA (r = -0.76, p = 0.006) and while breathing 30% O2 (r = -0.68, p = 0.02).
Conclusions: Using a clinically applicable level of O2 supplementation (30%) improved maximal, aerobic exercise capacity and V̇O2 kinetics in ILD patients, likely due to increased blood O2 content subsequently increasing the O2 delivery to the working muscles.
Competing Interests: Conflict of Interest and Funding Source: This work was supported by the G. Baum Fund of the Israeli Lung Association, Tel-Aviv. The authors have no conflict of interest and no financial disclosure related to this report.

Simovic T; Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA, United States.
Matheson C; Cobb K; Heefner A; Thode C; Colon M; Tunon E; Salmons H; Ahmed SI; Carbone S; Garten R; Breland A; Cobb CO; Nana-Sinkam P;
Rodriguez-Miguelez P;

Journal of applied physiology (Bethesda, Md. : 1985) [J Appl Physiol (1985)] 2024 Jul 11.
Date of Electronic Publication: 2024 Jul 11.

Background: Electronic nicotine delivery systems, often referred to as e-cigarettes, are popular tobacco products frequently advertised as safer alternatives to traditional cigarettes despite preliminary data suggesting a potential negative cardiovascular impact. Cardiorespiratory fitness is a critical cardiovascular health marker that is diminished in individuals who consume traditional tobacco products. Whether the use of e-cigarettes impacts cardiorespiratory fitness is currently unknown. Thus, the purpose of this study was to investigate the impact of regular e-cigarette use on cardiorespiratory fitness in young healthy adults.
Methods: Twenty-six users of e-cigarettes (ECU, 13 males, and 13 females; age: 24±3 yr; e-cigarette usage 4±2 yr.) and sixteen demographically matched non-users (NU, 6 males, and 10 females; age: 23±3 yr.) participated in this study. Cardiorespiratory fitness was measured by peak oxygen consumption (VO _2peak ) during a cardiopulmonary exercise test. Measurements of chronotropic response, hemodynamic, oxygen extraction and utilization were also evaluated.
Results: Our results suggest that regular users of e-cigarettes exhibited significantly lower peak oxygen consumption when compared to non-users, even when controlled by fat-free mass and lean body mass. Hemodynamic changes were not different between both groups during exercise, while lower chronotropic responses and skeletal muscle oxygen utilization were observed in users of e-cigarettes.
Conclusions: Results from the present study demonstrate that young, apparently healthy, regular users of e-cigarettes exhibit significantly reduced cardiorespiratory fitness, lower chronotropic response, and impaired skeletal muscle oxygen utilization during exercise. Overall, our findings contribute to the growing body of evidence that supports adverse effects of regular e-cigarette use on cardiovascular health.

Singh I; Division of Pulmonary, Critical Care, and Sleep Medicine,  New Haven, CT, USA inderjit.singh@yale.edu.
Waxman AB;

The European respiratory journal [Eur Respir J] 2024 Jul 11; Vol. 64 (1).
Date of Electronic Publication: 2024 Jul 11 (Print Publication: 2024).

No abstract available

Willixhofer R; Division of Cardiology, Medical University of Vienna.
Rettl R; Kronberger C; Ermolaev N; Gregshammer B; Duca F; Binder C; Kammerlander A; Alasti F; Kastner J; Bonderman D;
Bergler-Klein J; Agostoni P; Badr Eslam R;

Journal of cardiovascular medicine (Hagerstown, Md.) [J Cardiovasc Med (Hagerstown)] 2024 Jul 16.
Date of Electronic Publication: 2024 Jul 16.

Aims: Patients with transthyretin amyloid cardiomyopathy (ATTR-CM) experience reduced functional capacity. We evaluated changes in functional capacity over extensive follow-up using cardiopulmonary exercise testing (CPX).
Methods: ATTR-CM patients underwent CPX and blood testing at baseline, first [V1, 8 (6-10) months] and second follow-up (V2) at 35 (26-41) months after start of disease-specific therapy.
Results: We included 34 ATTR-CM patients, aged 77 (±6) years (88.2% men). CPX showed two patterns with functional capacity improvement at V1 and deterioration at V2. Peak work capacity (P = 0.005) and peak oxygen consumption (VO2, P = 0.012) increased at V1 compared with baseline and decreased at V2. The ventilation to carbon dioxide relationship slope (VE/VCO2) increased at V2 compared with baseline and V1 (P = 0.044). A cut-off for peak VO2 at 14 ml/kg·min showed more events (composite of death and heart failure hospitalization): less than 14 vs. greater than 14 ml/kg·min (P = 0.013). Cut-offs for VE/VCO2 slope at 40 showed more events greater than 40 vs. less than 40 (P = 0.009).
Conclusion: ATTR-CM patients showed an improvement and deterioration in the short-term and long-term follow-up, respectively, with a better prognosis for those with peak VO2 above 14 ml/kg·min and for a VE/VCO2 slope below 40.

Lopez J; JFK Hospital, Lantana, Florida, USA.
Liu Y; Butler J; Del Prato S; Ezekowitz JA; Lam CSP; Marwick TH;
Rosenstock J; Tang WHW; Perfetti R; Urbinati A; Zannad F; Januzzi JL Jr;
Ibrahim NE

Journal of the American College of Cardiology. 84(3):233-243, 2024 Jul 16.

BACKGROUND: Diabetic cardiomyopathy (DbCM) increases risk of overt heart
failure in individuals with diabetes mellitus. Racial and ethnic
differences in DbCM remain unexplored.

OBJECTIVES: The authors sought to identify racial and ethnic differences
among individuals with type 2 diabetes mellitus, structural heart disease,
and impaired exercise capacity.

METHODS: The ARISE-HF (Aldolase Reductase Inhibitor for Stabilization of
Exercise Capacity in Heart Failure) trial is assessing the efficacy of an
aldose reductase inhibitor for exercise capacity preservation in 691
persons with DbCM. Baseline characteristics, echocardiographic parameters,
and functional capacity were analyzed and stratified by race and
ethnicity.

RESULTS: The mean age of the study participants was 67.4 years; 50% were
women. Black and Hispanic patients had lower use of diabetes mellitus
treatments. Black patients had poorer baseline ventricular function and
more impaired global longitudinal strain. Overall, health status was
preserved, based on Kansas City Cardiomyopathy Questionnaire scores, but
reduced exercise capacity was present as evidenced by reduced Physical
Activity Scale for the Elderly (PASE) scores. When stratified by race and
ethnicity and compared with the entire cohort, Black patients had poorer
health status, more reduced physical activity, and a greater impairment in
exercise capacity during cardiopulmonary exercise testing, whereas
Hispanic patients also displayed compromised cardiopulmonary exercise
testing functional capacity. White patients demonstrated higher physical
activity and functional capacity.

CONCLUSIONS: Racial and ethnic differences exist in baseline
characteristics of persons affected by DbCM, with Black and Hispanic study
participants demonstrating higher risk features. These insights inform the
need to address differences in the population with DbCM. (Safety and
Efficacy of AT-001 in Patients With Diabetic Cardiomyopathy [ARISE-HF];
NCT04083339).

Busque V; Department of Medicine, Stanford University, California, USA
Christle JW; Moneghetti KJ; Cauwenberghs N; Kouznetsova T;
Blumberg Y; Wheeler MT; Ashley E; Haddad F; Myers J

Clinical Obesity. 14(4):e12653, 2024 Aug.

The goal of this study is to quantify the assumptions associated with the
Wasserman-Hansen (WH) and Fitness Registry and the Importance of Exercise:
A National Database (FRIEND) predictive peak oxygen consumption (pVO2)
equations across body mass index (BMI). Assumptions in pVO2 for both
equations were first determined using a simulation and then evaluated
using exercise data from the Stanford Exercise Testing registry. We
calculated percent-predicted VO2 (ppVO2) values for both equations and
compared them using the Bland-Altman method. Assumptions associated with
pVO2 across BMI categories were quantified by comparing the slopes of
age-adjusted VO2 ratios (pVO2/pre-exercise VO2) and ppVO2 values for
different BMI categories. The simulation revealed lower predicted fitness
among adults with obesity using the FRIEND equation compared to the WH
equations. In the clinical cohort, we evaluated 2471 patients (56.9% male,
22% with BMI >30 kg/m2, pVO2 26.8 mlO2/kg/min). The Bland-Altman plot
revealed an average relative difference of -1.7% (95% CI: -2.1 to -1.2%)
between WH and FRIEND ppVO2 values with greater differences among those
with obesity. Analysis of the VO2 ratio to ppVO2 slopes across the BMI
spectrum confirmed the assumption of lower fitness in those with obesity,
and this trend was more pronounced using the FRIEND equation. Peak VO2
estimations between the WH and FRIEND equations differed significantly
among individuals with obesity. The FRIEND equation resulted in a greater
attributable reduction in pVO2 associated with obesity relative to the WH
equations.
The outlined relationships between BMI and predicted VO2 may
better inform the clinical interpretation of ppVO2 values during
cardiopulmonary exercise test evaluations

Critser PJ; Department of Cardiology, Boston Children’s Hospital, Boston, MA.
Buchmiller TL; Gauvreau K; Zalieckas JM; Sheils CA; Visner GA;
Shafer KM; Chen MH; Mullen MP

Journal of Pediatrics. 271:114034, 2024 Aug.

OBJECTIVE: To determine the prevalence of exercise-induced pulmonary
hypertension (PH) among long-survivors of congenital diaphragmatic hernia (CDH)
repair.

STUDY DESIGN: This is a single-center, retrospective cohort study of CDH
survivors who underwent exercise stress echocardiography (ESE) at Boston
Children’s Hospital from January 2006 to June 2020. PH severity was
assessed by echocardiogram at baseline and after exercise. Patients were
categorized by right ventricular systolic pressure (RVSP) after exercise:
Group 1 – no or mild PH; and Group 2 – moderate or severe PH (RVSP >= 60
mmHg or >= 1/2 systemic blood pressure).

RESULTS: Eighty-four patients with CDH underwent 173 ESE with median age
8.1 (4.8 – 19.1) years at first ESE. Sixty-four patients were classified
as Group 1, 11 as Group 2, and 9 had indeterminate RVSP with ESE. Moderate
to severe PH after exercise was found in 8 (10%) patients with no or mild
PH at rest. Exercise-induced PH was associated with larger CDH defect
size, patch repair, use of ECMO, supplemental oxygen at discharge, and
higher WHO functional class. Higher VE/VCO2 slope, lower peak oxygen
saturation, and lower percent predicted FEV1, and FEV1/FVC ratio were
associated with Group 2 classification. ESE changed management in 9/11
Group 2 patients. PH was confirmed in all 5 Group 2 patients undergoing
cardiac catheterization after ESE.

CONCLUSIONS: Among long-term CDH survivors, 10% had moderate-severe
exercise-induced PH on ESE, indicating ongoing pulmonary vascular
abnormalities. Further studies are needed

Singh I; Division of Pulmonary, Critical Care, New Haven, CT, USA
Waxman AB

European Respiratory Journal. 64(1), 2024 Jul.

BACKGROUND: The direct Fick principle is the standard for calculating
cardiac output (CO) to detect CO-dependent conditions like exercise
pulmonary hypertension (ePH). Fick COarterial incorporates arterial
haemoglobin (Hba) and oxygen saturation (S aO2 ) with oxygen consumption
from exercise testing, while Fick COnon-arterial substitutes mixed venous
haemoglobin (Hbmv) and peripheral oxygen saturation (S pO2 ) in the
absence of an arterial line. The decision to employ an arterial catheter
for exercise testing varies, and discrepancies in oxygen saturation and
haemoglobin between arterial and non-arterial methods may lead to
differences in Fick CO, potentially affecting ePH classification.

METHODS: We performed a retrospective analysis of 296 consecutive
invasive cardiopulmonary exercise testing (iCPET) studies comparing oxygen
saturation from pulse oximetry (S pO2 ) and radial arterial (S aO2 ), Hba
and Hbmv, and CO calculated with arterial (COarterial) and non-arterial
(COnon-arterial) values. We assessed the risk of misclassification of pre-
and post-capillary ePH and data loss due to inaccurate S pO2 .

RESULTS: When considering all stages from rest to peak exercise, Hba and
Hbmv demonstrated high correlation, while S pO2 and S aO2 as well as
COarterial and COnon-arterial demonstrated low correlation. Data loss was
significantly higher across all stages of exercise for S pO2 (n=346/1926
(18%)) compared to S aO2 (n=17/1923 (0.88%)). We found that pre- and
post-capillary ePH were misclassified as COnon-arterial data (n=7/41
(17.1%) and n=2/23 (8.7%), respectively). Patients with scleroderma and/or
Raynaud’s (n=11/33 (33.3%)) and black patients (n=6/19 (31.6%)) had more S
pO2 data loss.

CONCLUSION: Reliance upon S pO2 during invasive exercise testing results
in the misclassification of pre- and post-capillary ePH, and unmeasurable
S pO2 for black, scleroderma and Raynaud’s patients can preclude accurate
exercise calculations, thus limiting the diagnostic and prognostic value
of invasive exercise testing without an arterial line.

de Souza IPMA; Cardio Pulmonar Hospital, Salvador, Bahia,Brazil
Ramos JVSP; da Silveira AD; Stein R; Ribeiro RS; Pazelli AM;
de Oliveira QB; Darze ES; Ritt LEF

PURPOSE: The objective of this study was to evaluate the independent and
added value of a cardiopulmonary exercise test (CPX) to New York Heart
Association (NYHA) functional analysis in patients with heart failure (HF)
and ejection fraction (EF) <50%.
METHODS: Patients (n = 613) with HF and EF < 50% underwent CPX and were
followed for 28 +/- 17 mo with respect to primary outcomes (death or heart
transplantation).
RESULTS: Mean patient age was 56 +/- 12 yr, and 64% were male. Most
patients were classified as NYHA class II (41%). The composite rate of
primary outcomes was 12%; death occurred in 9%, and heart transplant in
4%. Independent predictors of primary outcomes were: EF (HR = 0.95: 95%
CI, 0.92-0.98; P = .001) and NYHA (HR = 2.06: 95% CI, 1.54-2.75; P <
.0001). When added to the model, peak oxygen uptake (V O2peak ) was an
independent predictor (HR = 0.90: 95% CI, 0.84-0.96; P = .001), as was the
percentage of predicted V O2peak (HR = 0.03: 95% CI, 0.007-0.147; P <
.001), minute ventilation/carbon dioxide production slope (HR = 1.02: 95%
CI, 1.01-1.04; P = .012), and CPX score (HR = 1.16: 95% CI, 1.06-1.27; P =
.001).
CONCLUSIONS: CPX variables were independent predictors of HF prognosis,
even when controlled by NYHA functional class. Despite being independent
predictors, the value added to NYHA classification was modest and lacked
statistical significance.