Author Archives: Paul Older

Qualitative Components of Dyspnea during Incremental Exercise across the COPD Continuum.

Philips DB; Neder JA; Elbehairy AF; Milne KM; James MD; Vincent SG ;Day AG; de-Torres JP; Webb KA; O’Donnell DE;

Medicine and science in sports and exercise [Med Sci Sports Exerc] 2021 Jul 07.
Date of Electronic Publication: 2021 Jul 07.

Introduction: Evaluation of the intensity and quality of activity-related dyspnea is potentially useful in people with chronic obstructive pulmonary disease (COPD). The present study sought to examine associations between qualitative dyspnea descriptors, dyspnea intensity ratings, dynamic respiratory mechanics, and exercise capacity during cardiopulmonary exercise testing (CPET) in COPD and healthy controls.
Methods: In this cross-sectional study, 261 patients with mild-to-very severe COPD (forced expiratory volume in 1 second [FEV1] 62 ± 25 %pred) and 94 age-matched controls (FEV1 114 ± 14 %pred) completed an incremental cycle CPET to determine peak oxygen uptake (V[Combining Dot Above]O2peak). Throughout exercise, expired gases, operating lung volumes and dyspnea intensity were assessed. At peak exercise, dyspnea quality was assessed using a modified 15-item questionnaire.
Results: Logistic regression analysis revealed that amongst 15 dyspnea descriptors, only those alluding to the cluster “unsatisfied inspiration” were consistently associated with an increased likelihood for both critical inspiratory mechanical constraint (end-inspiratory lung volume/total lung capacity ratio ≥ 0.9) during exercise and reduced exercise capacity (V[Combining Dot Above]O2peak < lower limit of normal) in COPD (odds ratio [95% confidence interval] =3.26 [1.40-7.60] and 3.04 [1.24-7.45], respectively, both p < 0.05). Thus, patients reporting “unsatisfied inspiration” (n = 177 (68%)) had an increased relative frequency of critical inspiratory mechanical constraint and low exercise capacity, compared with those who did not select this descriptor, regardless of COPD severity or peak dyspnea intensity scores.
Conclusion: In patients with COPD, regardless of disease severity, reporting descriptors in the unsatisfied inspiration cluster complemented traditional assessments of dyspnea during CPET and helped identify patients with critical mechanical abnormalities germane to exercise intolerance.

Comparison between PtCO 2 and PaCO 2 and Derived Parameters in Heart Failure Patients during Exercise: A Preliminary Study.

Contini M; Angelucci A; Aliverti A; Gugliandolo P; Pezzuto B; Berna G; Romani S; Tedesco CC; Agostoni P;

Sensors (Basel, Switzerland) [Sensors (Basel)] 2021 Oct 07; Vol. 21 (19).
Date of Electronic Publication: 2021 Oct 07.

Evaluation of arterial carbon dioxide pressure (PaCO 2 ) and dead space to tidal volume ratio (V D /V T ) during exercise is important for the identification of exercise limitation causes in heart failure (HF). However, repeated sampling of arterial or arterialized ear lobe capillary blood may be clumsy. The aim of our study was to estimate PaCO 2 by means of a non-invasive technique, transcutaneous PCO 2 (PtCO 2 ), and to verify the correlation between PtCO 2 and PaCO 2 and between their derived parameters, such as V D /V T , during exercise in HF patients. 29 cardiopulmonary exercise tests (CPET) performed on a bike with a ramp protocol aimed at achieving maximal effort in ≈10 min were analyzed. PaCO 2 and PtCO 2 values were collected at rest and every 2 min during active pedaling. The uncertainty of PCO 2 and V D /V T measurements were determined by analyzing the error between the two methods. The accuracy of PtCO 2 measurements vs. PaCO 2 decreases towards the end of exercise. Therefore, a correction to PtCO 2 that keeps into account the time of the measurement was implemented with a multiple regression model. PtCO 2 and V D /V T changes at 6, 8 and 10 min vs. 2 min data were evaluated before and after PtCO 2 correction. PtCO 2 overestimates PaCO 2 for high timestamps (median error 2.45, IQR -0.635-5.405, at 10 min vs. 2 min, p -value = 0.011), while the error is negligible after correction (median error 0.50, IQR = -2.21-3.19, p -value > 0.05). The correction allows removing differences also in PCO 2 and V D /V T changes. In HF patients PtCO 2 is a reliable PaCO 2 estimation at rest and at low exercise intensity. At high exercise intensity the overall response appears delayed but reproducible and the error can be overcome by mathematical modeling allowing an accurate estimation by PtCO 2 of PaCO 2 and V D /V T .


Reference values for systolic blood pressure at upright bicycle exercise tests

Alfred Hager

European Journal of Preventive Cardiology, Volume 28, Issue 12, November 2021, Page e19,

Hedman et al. must be congratulated for their excellent work setting up reference values for systolic blood pressure (SPB) at upright bicycle exercise tests. However, they missed comparing their data with the now second-largest study by Heck et al. This study is published in German only and, therefore, is fairly unknown in the non-German speaking medical world. Almost 40 years ago the group in Cologne investigated the SPB response in a stepwise increasing bicycle ergometry with 16,656 measurements in 2972 subjects. They based their model on physiology and assumed that a baseline SBP rises linearly with increasing work load (WL). Now we know that they were…

Rays of light into the ‘black-box’ of exercise hypertension

Birna Bjarnason-Wehrens, Hans-Georg Predel

European Journal of Preventive Cardiology, 2047487320918343,
Based on resting arterial blood pressure (BP) measurements, the overall prevalence of arterial hypertension (AH) is high (30–45%) and increases with age. In people aged over 60 years the prevalence is estimated to be greater than 60%.1 Elevated BP is a leading global contributor to premature death showing an independent and continuous relationship with the incidence of several cardiovascular and renal diseases, starting at systolic blood pressure (SBP) and diastolic blood pressure (DBP) levels even as low as 115–110 mmHg and 75–70 mmHg, respectively…….

Age- and gender-specific upper limits and reference equations for workload-indexed systolic blood pressure response during bicycle ergometry


Background: Guidelines recommend considering workload in interpretation of the systolic blood pressure (SBP) response to exercise, but reference values are lacking.

Design: This was a retrospective, consecutive cohort study.

Methods: From 12,976 subjects aged 18-85 years who performed a bicycle ergometer exercise test at one centre in Sweden during the years 2005-2016, we excluded those with prevalent cardiovascular disease, comorbidities, cardiac risk factors or medications. We extracted SBP, heart rate and workload (watt) from ≥ 3 time points from each test. The SBP/watt-slope and the SBP/watt-ratio at peak exercise were calculated. Age- and sex-specific mean values, standard deviations and 90th and 95th percentiles were determined. Reference equations for workload-indexed and peak SBP were derived using multiple linear regression analysis, including sex, age, workload, SBP at rest and anthropometric variables as predictors.

Results: A final sample of 3839 healthy subjects (n = 1620 female) were included. While females had lower mean peak SBP than males (188 ± 24 vs 202 ± 22 mmHg, p < 0.001), workload-indexed SBP measures were markedly higher in females; SBP/watt-slope: 0.52 ± 0.21 versus 0.41 ± 0.15 mmHg/watt (p < 0.001); peak SBP/watt-ratio: 1.35 ± 0.34 versus 0.90 ± 0.21 mmHg/watt (p < 0.001). Age, sex, exercise capacity, resting SBP and height were significant predictors of the workload-indexed SBP parameters and were included in the reference equations.

Conclusions: These novel reference values can aid clinicians and exercise physiologists in interpreting the SBP response to exercise and may provide a basis for future research on the prognostic impact of exercise SBP. In females, a markedly higher SBP in relation to workload could imply a greater peripheral vascular resistance during exercise than in males.

Limited usefulness of resting hemodynamic assessments in predicting exercise capacity in hypertensive patients.

Kurpaska M; Krzesinski P; Gielerak G; Uzieblo-Zyczkowska B

Journal of Human Hypertension. 35(7):613-620, 2021 07. VI 1

Reliable assessments of reduced exercise capacity based on resting tests
are one of the major challenges in clinical practice. The aim of this
study was to evaluate the relationship between hemodynamic parameters
obtained via resting tests (echocardiography and impedance cardiography
(ICG)) and objective parameters of exercise capacity assessed via
cardiopulmonary exercise testing and exercise ICG in patients with
controlled arterial hypertension (AH). The left ventricular ejection
fraction (LVEF), global longitudinal strain (GLS), diastolic function
parameters (e’, E/A, E/e’), cardiac output (CO), stroke volume (SV), and
systemic vascular resistance index were evaluated for any correlations
with selected parameters of exercise capacity, such as peak oxygen uptake
(VO2) and peak CO in 93 people with AH (mean age 54 years, 47 women).
Statistically relevant correlations occurred between indices of exercise
capacity (peak VO2; peak CO) and only the following hemodynamic
parameters: diastolic blood pressure (R = 0.23, p = 0.026; R = 0.24, p =
0.021; respectively), e’ (R = 0.32, p = 0.002; R = 0.24, p = 0.027), E/e’
(R = 0.35, p < 0.001; ns), E/A (R = 0.23, p = 0.030; R = 0.21, p = 0.047),
SV at rest (ns; R = 0.24, p = 0.019), and CO at rest (ns; R = 0.21,
borderline p = 0.052). No significant correlations between the exercise
capacity parameters and either LVEF or GLS were observed. No hemodynamic
parameter proved to be an independent correlate of either peak VO2 or peak
CO. The association between hemodynamic parameters at rest and parameters
of exercise capacity was weak and limited to selected parameters of
diastolic function. Exercise capacity assessment in patients with AH based
on resting tests alone is insufficiently reliable and should be
supplemented with exercise tests.

Characterization of the blood pressure response during cycle ergometer cardiopulmonary exercise testing in black and white men : Data from the Fitness Registry and Importance of Exercise: A National Database (FRIEND).

Sabbahi A; Arena R; Kaminsky LA; Myers J; Fernhall B; Sundeep C;
Phillips SA

Journal of Human Hypertension. 35(8):685-695, 2021 08. VI 1

It has been established that blacks have higher overall incidence and
prevalence of hypertension compared to their white counterparts. However,
the maximum blood pressure (BP) response of blacks to exercise has not
been characterized. A total of 5996 apparently healthy men from the
Fitness Registry and Importance of Exercise: A National Database (FRIEND)
who underwent maximum cardiopulmonary exercise tests on a cycle ergometer
were included in this analysis. Of these participants, 1245 (21%)
self-identified as black while the remaining 4751 (79%) identified as
white. All subjects had a respiratory exchange ratio (RER) of >=1.0 and
had no reports of cardiovascular or pulmonary disease. Systolic BP (BP)
response to exercise was indexed according to increase in workload
(SBP/MET-slope). Both racial groups were subdivided into age groups by
decade. Black men had higher peak SBP and higher SBP/MET-slopes compared
to white men across all age groups (p < 0.001). Resting SBP was not
different between blacks and whites except within the 18-29-year age
group. The differences in peak SBP and SBP/MET-slope between age and race
groups indicate that black men have an exaggerated BP response to exercise
irrespective of resting BP values. Further investigation is warranted to
determine the underlying mechanisms responsible and clinical implications
for this exaggerated BP response to exercise.

Blood Lactate AUC Is a Sensitive Test for Evaluating the Effect of Exercise Training on Functional Work Capacity in Patients with Chronic Heart Failure.

Valborgland T; Isaksen K; Munk PS; Larsen AI;

Rehabilitation research and practice [Rehabil Res Pract] 2021 Sep 30; Vol. 2021, pp. 6619747.
Date of Electronic Publication: 2021 Sep 30 (Print Publication: 2021).

Purpose: Exercise training is an essential treatment option for patients with chronic heart failure (CHF). However, it remains controversial, which surrogate measures of functional work capacity are most reliable. The purpose of this paper was to compare functional capacity work measured as capillary lactate concentrations area under the curve (AUC) with standard cardiopulmonary exercise testing (CPET) with VO 2peak and the 6-minute walk test (6 MWT).
Methods: Twenty-three patients in New York Heart Association (NYHA) class II/III with left ventricular ejection fraction (LVEF) <35% were randomised to home-based recommendation of regular exercise (RRE) (controls), moderate continuous training (MCT) or aerobic interval training (AIT). The MCT and AIT groups underwent 12 weeks of supervised exercise training. Exercise testing was performed as standard CPET treadmill test with analysis of VO 2peak , the 6 MWT and a novel 30-minute submaximal treadmill test with capillary lactate AUC.
Results: All patients had statistically significant improvements in VO 2peak , 6 MWT and lactate AUC after 12 weeks of exercise training: 6 MWT (p =0.035), VO 2peak (p =0.049) and lactate AUC (p =0.002). Lactate AUC (p =0.046) and 6MWT (p =0.035), but not VO 2peak revealed difference between the exercise modalities regarding functional work capacity.
Conclusion: 6-MWT and lactate AUC, but not VO 2peak , were able to reveal a statistically significant improvement in functional capacity between different exercise modalities.

Preoperative physical performance as predictor of postoperative outcomes in patients aged 65 and older scheduled for major abdominal cancer surgery: A systematic review.

Argillander TE; Heil TC; Melis RJF; Klaase JM;

European journal of surgical oncology : the journal of the European Society of Surgical Oncology and the British Association of Surgical Oncology [Eur J Surg Oncol] 2021 Oct 01. Date of Electronic Publication: 2021 Oct 01.

Background: Abdominal cancer surgery is associated with considerable morbidity in older patients. Assessment of preoperative physical status is therefore essential. The aim of this review was to describe and compare the objective physical tests that are currently used in abdominal cancer surgery in the older patient population with regard to postoperative outcomes.
Methods: Medline, Embase, CINAHL and Web of Science were searched until 31 December 2020. Non-interventional cohort studies were eligible if they included patients ≥65 years undergoing abdominal cancer surgery, reported results on objective preoperative physical assessment such as Cardiopulmonary Exercise Testing (CPET), field walk tests or muscle strength, and on postoperative outcomes.
Results: 23 publications were included (10 CPET, 13 non-CPET including Timed Up & Go, grip strength, 6-minute walking test (6MWT) and incremental shuttle walk test (ISWT)). Meta-analysis was precluded due to heterogeneity between study cohorts, different cut-off points, and inconsistent reporting of outcomes. In CPET studies, ventilatory anaerobic threshold and minute ventilation/carbon dioxide production gradient were associated with adverse outcomes. ISWT and 6MWT predicted outcomes in two studies. Tests addressing muscle strength and function were of limited value. No study compared different physical tests.
Discussion: CPET has the ability to predict adverse postoperative outcomes, but it is time-consuming and requires expert assessment. ISWT or 6MWT might be a feasible alternative to estimate aerobic capacity. Muscle strength and function tests currently have limited value in risk prediction. Future research should compare the predictive value of different physical instruments with regard to postoperative outcomes in older surgical patients.