Category Archives: Abstracts

Lack of effect of an in-line filter on cardiopulmonary exercise testing variables in healthy subjects.

Abbasi A; Division of Respiratory and Critical Care Physiology and Medicine, Harbor-UCLA Medical Center,
Ahmad K; Ferguson C; Soriano A; Calmelat R;Rossiter HB; Casaburi R; Stringer WW; Porszasz J

European journal of applied physiology [Eur J Appl Physiol] 2023 Oct 06.
Date of Electronic Publication: 2023 Oct 06.

Purpose: Pathogen transmission during cardio-pulmonary exercise testing (CPET) is caused by carrier aerosols generated during respiration.
Methods: Ten healthy volunteers (age range: 34 ± 15; 4 females) were recruited to see if the physiological reactions to ramp-incremental CPET on a cycle ergometer were affected using an in-line filter placed between the mouthpiece and the flow sensor. The tests were in random order with or without an in-line bacterial/viral spirometer filter. The work rate aligned, time interpolated 10 s bin data were compared throughout the exercise period.
Results: From rest to peak exercise, filter use increased only minute ventilation ([Formula: see text] E ) (Δ[Formula: see text] E  = 1.56 ± 0.70 L/min, P < 0.001) and tidal volume (V T ) (ΔV T  = 0.10 ± 0.11 L, P = 0.014). Over the entire test, the slope of the residuals for [Formula: see text]CO 2 was positive (0.035 ± 0.041 (ΔL/L), P = 0.027). During a ramp-incremental CPET in healthy subjects, an in-line filter increased [Formula: see text] E and V T but not metabolic rate.
Conclusion: In conclusion, using an in-line filter is feasible, does not affect appreciably the physiological variables, and may mitigate risk of aerosol dispersion during CPET.

Breathing pattern and pulmonary gas exchange in elderly patients with and without left ventricular dysfunction-modification with exercise-based cardiac rehabilitation and prognostic value.

Eser P;  University of Bern, Switzerland & other centres in Netherlands, Italy, France & Spain
Marcin T; Prescott E; Prins LF; Kolkman E; Bruins W; van der Velde AE; Gil CP; Iliou MC; Ardissino D; Zeymer U; Meindersma EP;
Van’t Hof AWJ; de Kluiver EP; Wilhelm M;

Frontiers in cardiovascular medicine [Front Cardiovasc Med] 2023 Sep 01; Vol. 10, pp. 1219589.
Date of Electronic Publication: 2023 Sep 01 (Print Publication: 2023).

Background: Inefficient ventilation is an established prognostic marker in patients with heart failure. It is not known whether inefficient ventilation is also linked to poor prognosis in patients with left ventricular dysfunction (LVD) but without overt heart failure.
Objectives: To investigate whether inefficient ventilation in elderly patients with LVD is more common than in patients without LVD, whether it improves with exercise-based cardiac rehabilitation (exCR), and whether it is associated with major adverse cardiovascular events (MACE).
Methods: In this large multicentre observational longitudinal study, patients aged ≥65 years with acute or chronic coronary syndromes (ACS, CCS) without cardiac surgery who participated in a study on the effectiveness of exCR in seven European countries were included. Cardiopulmonary exercise testing (CPET) was performed before, at the termination of exCR, and at 12 months follow-up. Ventilation (VE), breathing frequency (BF), tidal volume (VT), and end-expiratory carbon dioxide pressure (P ET CO 2 ) were measured at rest, at the first ventilatory threshold, and at peak exercise. Ventilatory parameters were compared between patients with and without LVD (based on cardio-echography) and related to MACE at 12 month follow-up.
Results: In 818 patients, age was 72.5 ± 5.4 years, 21.9% were women, 79.8% had ACS, and 151 (18%) had LVD. Compared to noLVD, in LVD resting VE was increased by 8%, resting BF by 6%, peak VE , peak VT, and peak P ET CO 2 reduced by 6%, 8%, and 5%, respectively, and VE/VCO 2 slope increased by 11%. From before to after exCR, resting VE decreased and peak P ET CO 2 increased significantly more in patients with compared to without LVD. In LVD, higher resting BF, higher nadir VE/VCO 2 , and lower peak P ET CO 2 at baseline were associated with MACE.
Conclusions: Similarly to patients with HF, in elderly patients with ischemic LVD, inefficient resting and exercise ventilation was associated with worse outcomes, and ExCR alleviated abnormal breathing patterns and gas exchange parameters.

Age, sex, endurance capacity, and chronic heart failure affect central and peripheral factors of oxygen uptake measured by non-invasive and continuous technologies: support of pioneer work using invasive or non-continuous measures.

Brochhagen J;Faculty of Sport Science, Leipzig University,  Germany.
Coll Barroso MT; Baumgart C; Wasmus DT; Freiwald J; Hoppe MW;

Frontiers in sports and active living [Front Sports Act Living] 2023 Sep 05; Vol. 5, pp. 1218948.
Date of Electronic Publication: 2023 Sep 05 (Print Publication: 2023).

Introduction: It is known that maximum oxygen uptake depends on age, sex, endurance capacity, and chronic heart failure. However, due to the required invasive or often applied non-continuous approaches, less is known on underlying central and peripheral factors. Thus, this study aimed to investigate the effects of age, sex, endurance capacity, and chronic heart failure on non-invasively and continuously measured central and peripheral factors of oxygen uptake.
Methods: 15 male children (11 ± 1 years), 15 male (24 ± 3 years) and 14 female recreationally active adults (23 ± 2 years), 12 male highly trained endurance athletes (24 ± 3 years), and 10 male elders (59 ± 6 years) and 10 chronic heart failure patients (62 ± 7 years) were tested during a cardiopulmonary exercise test on a cycling ergometer until exhaustion for: blood pressure, heart rate, stroke volume, cardiac output, cardiac power output, vastus lateralis muscle oxygen saturation, and (calculated) arterio-venous oxygen difference. For the non-invasive and continuous measurement of stroke volume and muscle oxygen saturation, bioreactance analysis and near-infrared spectroscopy were used, respectively. A two-factor repeated measure ANOVA and partial eta-squared effect sizes ( η p 2 ) were applied for statistical analyses at rest, 80, and 100% of oxygen uptake.
Results: For the age effect, there were statistically significant group differences for all factors ( p  ≤ .033; η p 2 ≥ .169 ). Concerning sex, there were group differences for all factors ( p  ≤ .010; η p 2 ≥ .223 ), except diastolic blood pressure and heart rate ( p  ≥ .698; η p 2 ≤ .006 ). For the effect of endurance capacity, there were no group differences for any of the factors ( p  ≥ .065; η p 2 ≤ .129 ). Regarding chronic heart failure, there were group differences for the heart rate and arterio-venous oxygen difference ( p  ≤ .037; η p 2 ≥ .220 ).
Discussion: Age, sex, endurance capacity, and chronic heart failure affect central and peripheral factors of oxygen uptake measured by non-invasive and continuous technologies. Since most of our findings support pioneer work using invasive or non-continuous measures, the validity of our applied technologies is indirectly confirmed. Our outcomes allow direct comparison between different groups serving as reference data and framework for subsequent studies in sport science and medicine aiming to optimise diagnostics and interventions in athletes and patients.

Socioeconomic Factors Influencing Pediatric Peak Oxygen Consumption Prediction.

Mistry MS; Boston Children’s Hospital, Department of Cardiology.
Gauvreau K; Alexander ME; Jenkins K; Gauthier N;

The Journal of pediatrics [J Pediatr] 2023 Sep 18, pp. 113742.
Date of Electronic Publication: 2023 Sep 18.

Objectives: To determine socioeconomic status (SES) has a greater effect than standard demographic values on predicted peak oxygen consumption (pVO 2 ).
Study Design: We conducted a single-institution, retrospective analysis of maximal cardiopulmonary exercise test (CPET) data from 2010 to 2020 for healthy patients age <19 years with BMI percentile (BMI%) between 5-95. Data were sorted by self-identified race, BMI%, and adjusted gross income (AGI); AGI served as a surrogate for SES. Mean percent predicted pVO 2 (%ppVO 2 ) was compared between groups. Linear regression was used to adjust for differences.
Results: 541 CPETs met inclusion criteria. Mean %ppVO 2 was 97% ± 22.6 predicted (p<0.01) with 30% below criterion standard for normal (85% predicted). After excluding unknown AGI and race, 418 CPETs remained. Mean %ppVO 2 was lower for Blacks (n=36) and LatinX (n=26) compared with Whites (n=333, p<0.01). Mean %ppVO 2 declined as AGI decreased (p<0.01). The differences in %ppVO 2 between racial categories remained significant when adjusted for BMI% (Black r=-7.3, p=0.035; LatinX r=-15.4, p<0.01). These differences both decreased in magnitude and were no longer significant when adjusted for AGI (Black r=-6.0, p=0.150; LatinX r=-9.3, p=0.06).
Conclusions: Lower SES correlates with lower measured cardiovascular fitness and may confound data interpretation. When using normative reference ranges in clinical decision making, providers should recognize that social determinants of health may influence predicted fitness. Social inequities should be considered when assessing pediatric cardiovascular fitness.

Haemodynamic and metabolic phenotyping of patients with aortic stenosis and preserved ejection fraction: a specific phenotype of heart failure with preserved ejection fraction?

De Biase N; (Department of Clinical and Experimental Medicine, University of Pisa, Italy.)
Mazzola M; Del Punta L; Di Fiore V;De Carlo M; Giannini C; Costa G; Paneni F; Mengozzi A; Nesti L; Gargani L; Masi S; Pugliese NR;

European journal of heart failure [Eur J Heart Fail] 2023 Sep 01.
Date of Electronic Publication: 2023 Sep 01.

Aims: Degenerative aortic valve stenosis with preserved ejection fraction (ASpEF) and heart failure with preserved ejection fraction (HFpEF) display intriguing similarities. This study aimed to provide a non-invasive, comparative analysis of ASpEF versus HFpEF at rest and during exercise.
Methods and Results: We prospectively enrolled 148 patients with HFpEF and 150 patients with degenerative moderate-to-severe ASpEF, together with 66 age- and sex-matched healthy controls. All subjects received a comprehensive evaluation at rest and 351/364 (96%) performed a combined cardiopulmonary exercise stress echocardiography test. Patients with ASpEF eligible for transcatheter aortic valve replacement (n = 125) also performed cardiac computed tomography (CT). HFpEF and ASpEF patients showed similar demographic distribution and biohumoral profiles. Most patients with ASpEF (134/150, 89%) had severe high-gradient aortic stenosis; 6/150 (4%) had normal-flow, low-gradient ASpEF, while 10/150 (7%) had low-flow, low-gradient ASpEF. Both patient groups displayed significantly lower peak oxygen consumption (VO 2 ), peak cardiac output, and peak arteriovenous oxygen difference compared to controls (all p < 0.01). ASpEF patients showed several extravalvular abnormalities at rest and during exercise, similar to HFpEF (all p < 0.01 vs. controls). Epicardial adipose tissue (EAT) thickness was significantly greater in ASpEF than HFpEF and was inversely correlated with peak VO 2 in all groups. In ASpEF, EAT was directly related to echocardiography-derived disease severity and CT-derived aortic valve calcium burden.
Conclusion: Functional capacity is similarly impaired in ASpEF and HFpEF due to both peripheral and central components. Further investigation is warranted to determine whether extravalvular alterations may affect disease progression and prognosis in ASpEF even after valve intervention, which could support the concept of ASpEF as a specific sub-phenotype of HFpEF.

Determinants of Anaerobic Threshold at Each Stage of Renal Dysfunction in Patients With Heart Disease.

Ogura A;  (Cardiovascular Stroke Renal Project (CRP), Hyogo, Japan.)
Izawa KP; Tawa H; Wada M;Kanai M; Kubo I; Makihara A; Yoshikawa R; Matsuda Y;

The American journal of cardiology [Am J Cardiol] 2023 Sep 07; Vol. 205, pp. 387-392.
Date of Electronic Publication: 2023 Sep 07.

Patients with heart disease have a low anaerobic threshold (AT), and the determinants of AT may differ, depending on the severity of renal dysfunction. This study aimed to verify the determinants of AT for each stage of renal function in patients with heart disease. We consecutively enrolled 250 patients with heart disease who underwent cardiopulmonary exercise testing in our institution. The patients were divided into 3 groups by their estimated glomerular filtration rate (eGFR): <45, 45 to 59, and ≥60 ml/min/1.73 m 2 . A multivariate linear regression analysis was performed to evaluate the independent determinants of AT for each group. In total, 201 patients were analyzed. AT decreased with the deterioration of renal function (eGFR <45, 10.9 ± 2.1 vs eGFR 45 to 59, 12.4 ± 2.5 vs eGFR ≥60, 14.0 ± 2.6 ml/min/kg, p <0.001). In the eGFR <45 group, left ventricular ejection fraction and hemoglobin were significantly associated with AT (β = 0.427, p = 0.006 and β = 0.488, p = 0.002, respectively). In the eGFR 45 to 59 and ≥60 groups, ΔP ET O 2 (end-tidal oxygen partial pressure from rest to AT) showed a significant association with AT (β = 0.576, p <0.001 and β = 0.308, p = 0.003, respectively). The determinants of AT depended on the stage of renal dysfunction in patients with heart disease. In conclusion, in the eGFR <45 group, the determinants of AT were left ventricular ejection fraction and hemoglobin, whereas in the eGFR 45 to 59 and eGFR ≥60 groups, the determinant of AT was ΔP ET O 2 .

Accelerometer Metrics: Healthy Adult Reference Values, Associations with Cardiorespiratory Fitness, and Clinical Implications.

Schwendinger F; (University of Basel, Basel, SWITZERLAND.)
Wagner J; Knaier R; Infanger D; Rowlands AV;Hinrichs T; Schmidt-Trucksäss A;

Medicine and science in sports and exercise [Med Sci Sports Exerc] 2023 Sep 13.
Date of Electronic Publication: 2023 Sep 13.

Purpose: Accelerometer-assessed physical activity (PA) can be summarised using cut-point-free or population-specific cut-point-based outcomes. We aimed to: 1) examine the interrelationship between cut-point-free (intensity gradient [IG] and average acceleration [AvAcc]) and cut-point-based accelerometer metrics, 2) compare the association between cardiorespiratory fitness (CRF) and cut-point-free metrics to that with cut-point-based metrics in healthy adults aged 20 to 89 years and patients with heart failure, and 3) provide age-, sex-, and CRF-related reference values for healthy adults.
Methods: In the COmPLETE study, 463 healthy adults and 67 patients with heart failure wore GENEActiv accelerometers on their non-dominant wrist and underwent cardiopulmonary exercise testing. Cut-point-free (IG: distribution of intensity of activity across the day; AvAcc: proxy of volume of activity) and traditional (moderate-to-vigorous and vigorous activity) metrics were generated. The ‘interpretablePA’ R-package was developed to translate findings into clinical practice.
Results: IG and AvAcc yield complementary information on PA with both IG (p = 0.009) and AvAcc (p < 0.001) independently associated with CRF in healthy individuals (adjusted R2 = 73.9%). Only IG was independently associated with CRF in patients with heart failure (p = 0.043, adjusted R2 = 38.4%). The best cut-point-free and cut-point-based model had similar predictive value for CRF in both cohorts. We produced age- and sex-specific reference values and percentile curves for IG, AvAcc, moderate-to-vigorous PA, and vigorous PA for healthy adults.
Conclusions: IG and AvAcc are strongly associated with CRF and, thus, indirectly with the risk of non-communicable diseases and mortality, in healthy adults and patients with heart failure. However, unlike cut-point-based metrics, IG and AvAcc are comparable across populations. Our reference values provide a healthy age- and sex-specific comparison that may enhance the translation and utility of cut-point-free metrics in clinical practice.
Competing Interests: Conflict of Interest and Funding Source: The COmPLETE study was funded by the Swiss National Science Foundation (Grant no. 182815). AVR is supported by the Lifestyle Theme of the Leicester NHR Leicester Biomedical Research Centre and NIHR Applied Research Collaborations East Midlands (ARC-EM). The authors declare that they have no competing interests. The results of the study are presented clearly, honestly, and without fabrication, falsification, or inappropriate data manipulation. The results of the present study do not constitute endorsement by the American College of Sports Medicine.

A Preoperative Supervised Exercise Programme Potentially Improves Long-Term Survival After Elective Abdominal Aortic Aneurysm Repair.

Sethi S;  (Hull York Medical School, Hull, UK.)
Ravindhran B; Long J; Gurung R;Huang C; Smith GE; Carradice D; Wallace T; Ibeggazene S; Chetter I; Pymer S;

Journal of vascular surgery [J Vasc Surg] 2023 Sep 13.
Date of Electronic Publication: 2023 Sep 13.

Introduction: A preoperative supervised exercise programme (SEP) improves cardiorespiratory fitness and perioperative outcomes for patients undergoing elective abdominal aortic aneurysm (AAA) repair. The aim of this study was to assess the effect of a preoperative SEP on long-term survival of these patients. A secondary aim was to consider long-term changes in cardiorespiratory fitness and quality of life.
Methods: Patients scheduled for open or endovascular AAA repair were previously randomized to either a 6-week preoperative SEP or standard management and a significant improvement in a composite outcome of cardiac, pulmonary, and renal complications was seen following SEP. For the current analysis, patients were followed up to five years post-surgery. The primary outcome for this analysis was all-cause mortality. Data were analysed on an intention to treat (ITT) and per protocol (PP) basis, with the latter meaning that patients randomised to SEP who did not attend any sessions, were excluded. The PP analysis was further interrogated using a complier average causal effect (CACE) analysis on an all or nothing scale, which adjusts for compliance. Additionally, patients who agreed to follow-up attended the research centre for cardiopulmonary exercise testing and/or provided QoL measures.
Results: ITT analysis demonstrated that the primary endpoint occurred in 24 of the 124 participants at five years, with 8 in the SEP group and 16 in the control group (p = 0.08). The PP analysis demonstrated a significant survival benefit associated with SEP attendance (4 vs. 16 deaths p = 0.01). CACE analysis confirmed a significant intervention effect (HR = 0.36; 95% CI: 0.16, 0.90; p = 0.02). There was no difference between groups for cardiorespiratory fitness measures and most QoL measures.
Conclusion: These novel findings suggest a long-term mortality benefit for patients attending a SEP prior to elective AAA repair. The underlying mechanism remains unknown, and this merits further investigation.

Heart failure patients with improved ejection fraction: insights from the MECKI Score database.

Agostoni P;  (Centro Cardiologico Monzino, IRCCs, Milan, Italy.)
Pluchinotta FR; Salvioni E; et al.

European journal of heart failure [Eur J Heart Fail] 2023 Sep 13.
Date of Electronic Publication: 2023 Sep 13.

Aims: Improvement of left ventricular ejection fraction is a major goal of heart failure (HF) treatment. However, data on clinical characteristics, exercise performance and prognosis in HF patients who improved ejection fraction (HFimpEF) are scarce. The study aimed to determine whether HFimpEF patients have a distinct clinical phenotype, biology and prognosis than HF patients with persistently reduced ejection fraction (pHFrEF).
Methods and Results: 7948 patients enrolled in the Metabolic Exercise Cardiac Kidney Indexes (MECKI) score database were evaluated (median follow-up of 1490 days). We analyzed clinical, laboratory, ECG, echocardiographic, exercise, and survival data from HFimpEF (n = 1504) and pHFrEF (n = 6017) patients. The primary endpoint of the study was the composite of cardiovascular death, left ventricular assist device implantation, and urgent heart transplantation. HFimpEF patients had lower HF severity: LVEF 44.0[41.0-47.0] vs. 29.7[24.1-34.5]%, BNP 122[65-296] vs. 373[152-888] pg/mL, hemoglobin 13.5[12.2-14.6] vs. 13.7[12.5-14.7] g/dL, renal function by MDRD 72.0[56.7-89.3] vs. 70.4[54.5-85.3] mL/min, peakVO 2 62.2[50.7-74.1] vs. 52.6[41.8-64.3]%pred, VE/VCO 2 slope 30.0[26.9-34.4] vs. 32.1[28.0-38.0] in HFimpEF and pHFrEF, respectively (p < 0.001 for all). Cardiovascular mortality rates were 26.6 and 46.9 per 1000 person-years for HFimpEF and pHFrEF, respectively (p < 0.001). Kaplan-Meier analysis showed that HFimpEF had better a long-term prognosis compared with pHFrEF patients. After adjustment for variables differentiating HFimpEF from pHFrEF, except echocardiographic parameters, the Kaplan-Meier curves showed the same prognosis.
Conclusions: HFimpEF represents a peculiar group of HF patients whose clinical, laboratory, ECG, echocardiographic, and exercise characteristics parallel the recovery of systolic function. Nonetheless, these patients remain at risk for adverse outcome.