Author Archives: Paul Older

The Maximal Oxygen Uptake Verification Phase: a Light at the End of the Tunnel?

Schaun GZ

Sports Med Open. 2017 Dec 8;3(1):44. doi: 10.1186/s40798-017-0112-1.

Commonly performed during an incremental test to exhaustion, maximal oxygen
uptake (V̇O2max) assessment has become a recurring practice in clinical and
experimental settings. To validate the test, several criteria were proposed. In
this context, the plateau in oxygen uptake (V̇O2) is inconsistent in its
frequency, reducing its usefulness as a robust method to determine “true”
V̇O2max. Moreover, secondary criteria previously suggested, such as expiratory
exchange ratios or percentages of maximal heart rate, are highly dependent on
protocol design and often are achieved at V̇O2 percentages well below V̇O2max.
Thus, an alternative method termed verification phase was proposed. Currently, it
is clear that the verification phase can be a practical and sensitive method to
confirm V̇O2max; however, procedures to conduct it are not standardized across
the literature and no previous research tried to summarize how it has been
employed. Therefore, in this review the knowledge on the verification phase was
updated, while suggestions on how it can be performed (e.g. intensity, duration,
recovery) were provided according to population and protocol design. Future
studies should focus to identify a verification protocol feasible for different
populations and to compare square-wave and multistage verification phases.
Additionally, studies assessing verification phases in different patient
populations are still warranted.

Repeatability and Meaningful Change of CPET Parameters in Normal Subjects.

DeCato TW, Bradley SM, Wilson EL, Hegewold MJ

Medicine And Science In Sports And Exercise [Med Sci Sports Exerc] 2017 Nov 07. Date of Electronic Publication: 2017 Nov 07.

Introduction/purpose: Cardiopulmonary exercise testing (CPET) plays an important role in clinical medicine and research. Repeatability of CPET parameters has not been well characterized, but is important to assess variability and determine if there have been meaningful changes in a given CPET parameter.
Methods: We recruited 45 healthy subjects and performed two symptom-limited CPETs within 30 days using a cycle ergometer. Differences in relevant CPET parameters between CPET-1 and CPET-2 were assessed using a paired t-test. Coefficient of variation (CoV) and Bland-Altman plots are reported. Factors that may be associated with variability were analyzed (sex, age, time of day, fitness level). The coefficient of repeatability was calculated for peak V˙O2 and V˙O2 at lactate threshold (LT) to establish a 95% threshold for meaningful change.
Results: There were no significant differences between tests in the parameters reported. Specifically, we found overall low CoV in peak V˙O2 (4.9%), V˙O2@LT (10.4%), peak O2 pulse (4.6%), peak V˙E (7.4%), V˙E/V˙CO2@LT (4.0%) andV˙E/V˙O2@LT (4.8%). The CoV for RER@LT was significantly affected by diurnal factors; age, sex and fitness level did not impact variability. The 95% threshold for meaningful change in peak V˙O2 was 0.540 L/min and for V˙O2@LT was 0.520 L/min.
Conclusions: Repeatability of CPET parameters is generally higher then previously reported. There were no significant differences in variability related to sex, age, fitness level; diurnal factors had a limited impact. The threshold for meaningful change in peak V˙O2 and for V˙O2@LT should be considered when gauging a response to therapies or training.

Pregnancy After Transcatheter Pulmonary Valve Implantation.

Kozicka U; Weroński K; Rużyłło W; Demkow M; Kowalski M; Śpiewak M;
Piotrowicz E; Siudalska H; Hoffman P; Biernacka EK

The Canadian Journal Of Cardiology [Can J Cardiol], ISSN: 1916-7075, 2017 Dec; Vol.
33 (12), pp. 1737.e5-1737

Transcatheter pulmonary valve implantation (TPVI) is a relatively new
method of treating patients with significant pulmonary regurgitation or
pulmonary stenosis, or both, after reconstruction of the right
ventricular outflow tract. It is an attractive alternative to conduit
replacement in this group of patients, who are typically young and
active. This report includes 4 young women who after successful TPVI
became pregnant and gave birth. Transthoracic echocardiography,
cardiopulmonary exercise testing, and cardiac magnetic resonance
imaging were performed in all patients. The results suggest that
pregnancy and delivery after successful TPVI is safe when the
appropriate precautions have been taken.Copyright © 2017 Canadian
Cardiovascular Society.

Repeatability and Meaningful Change of CPET Parameters in Normal Subjects

DeCato TW, Bradley SM, Wilson EL, Hegewald MJ.

Med Sci Sports Exerc. 2017 Nov 7. doi: 10.1249. [Epub ahead
of print]

INTRODUCTION/PURPOSE: Cardiopulmonary exercise testing (CPET) plays an important
role in clinical medicine and research. Repeatability of CPET parameters has not
been well characterized, but is important to assess variability and determine if
there have been meaningful changes in a given CPET parameter.
METHODS: We recruited 45 healthy subjects and performed two symptom-limited CPETs
within 30 days using a cycle ergometer. Differences in relevant CPET parameters
between CPET-1 and CPET-2 were assessed using a paired t-test. Coefficient of
variation (CoV) and Bland-Altman plots are reported. Factors that may be
associated with variability were analyzed (sex, age, time of day, fitness level).
The coefficient of repeatability was calculated for peak V˙O2 and V˙O2 at lactate
threshold (LT) to establish a 95% threshold for meaningful change.
RESULTS: There were no significant differences between tests in the parameters
reported. Specifically, we found overall low CoV in peak V˙O2 (4.9%), V˙O2@LT
(10.4%), peak O2 pulse (4.6%), peak V˙E (7.4%), V˙E/V˙CO2@LT (4.0%)
andV˙E/V˙O2@LT (4.8%). The CoV for RER@LT was significantly affected by diurnal
factors; age, sex and fitness level did not impact variability. The 95% threshold
for meaningful change in peak V˙O2 was 0.540 L/min and for V˙O2@LT was 0.520
L/min.
CONCLUSIONS: Repeatability of CPET parameters is generally higher then previously
reported. There were no significant differences in variability related to sex,
age, fitness level; diurnal factors had a limited impact. The threshold for
meaningful change in peak V˙O2 and for V˙O2@LT should be considered when gauging
a response to therapies or training.

Recovery of the cardiac autonomic nervous and vascular system after maximal cardiopulmonary exercise testing in recreational athletes.

Weberruss H; Maucher J; Oberhoffer R; Müller J,

European Journal Of Applied Physiology [Eur J Appl Physiol], ISSN: 1439-6327, 2017 Nov 15;

Objective: The body’s adaptation to physical exercise is modulated by sympathetic and parasympathetic (vagal) branches of the autonomic nervous system (ANS). Heart rate variability (HRV), the beat-to-beat variation of the heart, is a proxy measure for ANS activity, whereas blood pressure (BP) is an indicator for cardiovascular function. Impaired vagal activity and lower BP is already described after exercise. However, inconsistent results exist about how long vagal recovery takes and how long post-exercise hypotension persists. Therefore, the aim of this study was to assess HRV and BP 1 h after maximal cardiopulmonary exercise testing (CPET).
Patients and Methods: HRV (Polar RS800CX), peripheral and central BP (Mobil-O-Graph®) were prospectively studied in 107 healthy volunteers (47 female, median age 29.0 years) in supine position, before and 60 min after maximal CPET.
Results: One hour after terminating CPET measures of HRV were still impaired and post-exercise BP was significantly reduced suggesting an improved vascular function compared to pre levels. HRV parameters post-exercise were 34.7% (RMSSD), 67.2% (pNN50), 57.2% (HF), and 42.7% (LF) lower compared to pre-exercise levels (for all p < 0.001). Median reduction in BP was 5 mmHg for systolic BP (p < 0.001), and 4 mmHg for diastolic BP (p = 0.016) and central systolic post-exercise (p = 0.005).
Conclusions: One hour after terminating strenuous exercise, autonomic nervous regulation seems to be postponed which is reflected in reduced HRV, whereas the early recovery of the vasculature, post-exercise hypotension, is still preserved over the recovery period of 1 h.

Exercise testing in patients with diaphragm paresis

Palau P; Domínguez E; Núñez J,

European Journal Of Heart Failure [Eur J Heart Fail], ISSN: 1879-0844, 2017 Nov 16;

Purpose: Diaphragm paresis (DP) is characterized by abnormalities of respiratory muscle function. However, the impact of DP on exercise capacity is not well known. This study was performed to assess exercise tolerance in patients with DP and to determine whether inspiratory muscle function was related to exercise capacity, ventilatory pattern and cardiovascular function during exercise.
Methods: This retrospective study included patients with DP who underwent both diaphragmatic force measurements, and cardiopulmonary exercise testing (CPET).
Results: Fourteen patients were included. Dyspnea was the main symptom limiting exertion (86%). Exercise capacity was slightly reduced (median VO2peak: 80% [74.5%-90.5%]), mostly due to ventilatory limitation. Diaphragm and overall inspiratory muscle function were correlated with exercise ventilation. Moreover, overall inspiratory muscle function was related with oxygen consumption (r=0.61) and maximal workload (r=0.68).
Conclusions: DP decreases aerobic capacity due to ventilatory limitation. Diaphragm function is correlated with exercise ventilation whereas overall inspiratory muscle function is correlated with both exercise capacity and ventilation suggesting the importance of the accessory inspiratory muscles during exercise for patients with DP. Further larger prospective studies are needed to confirm these results.

Brockenhurst Practicum 2017

The meeting was  a meeting of POETTS, EBPOM as well as CPX International Inc.
The convenor was Professor M. Grocott

The Board consisted of P. Agostoni (President), A. Hager, D. Dumitrescu, M. Grocott,  M. Riley,
T. Takken, P. Older

The Board appointed Professor M. Grocott to be Vice President and the Board size to be increased to 9 members,

Left ventricular end-diastolic dimension and septal e’ are predictors of cardiac index at rest, while tricuspid annular plane systolic excursion is a predictor of peak oxygen uptake in patients with pulmonary hypertension

Nakano Y, Okumura N, Adachi S, Shimokata S, Tajima F, Kamimura
Y, Murohara T, Kondo T

Heart Vessels. 2017 Nov 15

Little is known regarding a correlation of hemodynamics at rest or exercise
capacity with echocardiographic parameters in patients with pulmonary
hypertension (PH). To clarify these potential correlations, we performed
transthoracic echocardiography, right heart catheterization, and cardiopulmonary
exercise testing in 53 patients with pulmonary arterial hypertension (PAH) and
chronic thromboembolic pulmonary hypertension (CTEPH). Left ventricular
end-diastolic dimension (LVDd), early diastolic velocity of the septal mitral
annulus (septal e’), tricuspid regurgitation peak gradient (TRPG), and tricuspid
annular plane systolic excursion (TAPSE) were significantly correlated with
cardiac index (LVDd; r = 0.477, P < 0.001, septal e’; r = 0.463, P = 0.001, TRPG;
r = – 0.455, P = 0.001 and TAPSE; r = 0.406, P = 0.003, respectively). Multiple
regression analysis revealed that LVDd and septal e’ were significantly
associated with cardiac index (CI) and stroke volume index at rest. Among the
exercise capacity markers evaluated, TAPSE, TRPG, and LVDd were significantly
correlated with peak oxygen uptake (TAPSE; r = 0.534, P < 0.001, TRPG;
r = – 0.466, P = 0.001 and LVDd; r = 0.411, P = 0.002, respectively). Multiple
regression analysis showed that TAPSE was significantly associated with peak
oxygen uptake (VO2). In PAH and CTEPH patients, LVDd and septal e’ were
significantly associated with CI at rest, whereas TAPSE was significantly
associated with peak VO2. Echocardiographic parameters may predict the prognostic
factors of PAH and CTEPH patients.

Recovery of the cardiac autonomic nervous and vascular system after maximal cardiopulmonary exercise testing in recreational athletes.

Weberruss H, Maucher J, Oberhoffer R, Müller J

Eur J Appl Physiol. 2017 Nov 15

OBJECTIVE: The body’s adaptation to physical exercise is modulated by sympathetic
and parasympathetic (vagal) branches of the autonomic nervous system (ANS). Heart
rate variability (HRV), the beat-to-beat variation of the heart, is a proxy
measure for ANS activity, whereas blood pressure (BP) is an indicator for
cardiovascular function. Impaired vagal activity and lower BP is already
described after exercise. However, inconsistent results exist about how long
vagal recovery takes and how long post-exercise hypotension persists. Therefore,
the aim of this study was to assess HRV and BP 1 h after maximal cardiopulmonary
exercise testing (CPET).
PATIENTS AND METHODS: HRV (Polar RS800CX), peripheral and central BP
(Mobil-O-Graph(®)) were prospectively studied in 107 healthy volunteers (47
female, median age 29.0 years) in supine position, before and 60 min after
maximal CPET.
RESULTS: One hour after terminating CPET measures of HRV were still impaired and
post-exercise BP was significantly reduced suggesting an improved vascular
function compared to pre levels. HRV parameters post-exercise were 34.7% (RMSSD),
67.2% (pNN50), 57.2% (HF), and 42.7% (LF) lower compared to pre-exercise levels
(for all p < 0.001). Median reduction in BP was 5 mmHg for systolic BP
(p < 0.001), and 4 mmHg for diastolic BP (p = 0.016) and central systolic
post-exercise (p = 0.005).
CONCLUSIONS: One hour after terminating strenuous exercise, autonomic nervous
regulation seems to be postponed which is reflected in reduced HRV, whereas the
early recovery of the vasculature, post-exercise hypotension, is still preserved
over the recovery period of 1 h

Evidence on Exercise Training in Pulmonary Hypertension.

Babu AS, Arena R, Morris NR

Adv Exp Med Biol. 2017;1000:153-172.

Pulmonary hypertension (PH) is a chronic, debilitating condition which gravely
affects exercise tolerance and quality of life. Though most therapies focus
purely on medical intervention, there is a growing body of evidence to suggest
the role and benefits of exercise training. This chapter discusses the various
physiological basis for exercise intolerance observed in PH and highlights the
rationale for exercise training. Recent evidence related to exercise training is
summarized and potential pathways to suggest adaptations to exercise training are
put forward. While keeping the paper applicable to clinicians, details on
evaluating exercise intolerance, prescribing exercise and setting up
rehabilitation centers for PH are discussed