Category Archives: Publications

Association of six-minute walk test distance with postoperative complications in non-cardiac surgery: a secondary analysis of a multicentre prospective cohort study.

Ramos RJ; Ladha KS; Cuthbertson BH; Shulman MA; Myles PS; Wijeysundera DN;

Canadian journal of anaesthesia = Journal canadien d’anesthesie [Can J Anaesth] 2021 Apr; Vol. 68 (4), pp. 514-529. Date of Electronic Publication: 2021 Jan 13.

Purpose: The six-minute walk test (6MWT) is a simple and valid test for assessing cardiopulmonary fitness. Nevertheless, the relationship between preoperative 6MWT distance and postoperative complications is uncertain. We conducted a secondary analysis of the 6MWT nested cohort substudy of the Measurement of Exercise Tolerance before Surgery study to determine if 6MWT distance predicts postoperative complications or death.
Methods: This analysis included 545 adults (≥ 40 yr) who were at elevated cardiac risk and had elective inpatient non-cardiac surgery at 15 hospitals in Canada, Australia, and New Zealand. Each participant performed a preoperative 6MWT and was followed for 30 days after surgery. The primary outcome was moderate or severe in-hospital complications. The secondary outcome was 30-day death or myocardial injury. Multivariable logistic regression modelling was used to characterize the adjusted association of 6MWT distance with these outcomes.
Results: Seven participants (1%) terminated their 6MWT sessions early because of lower limb pain, dyspnea, or dizziness. Eighty-one (15%) participants experienced moderate or severe complications and 69 (13%) experienced 30-day myocardial injury or death. Decreased 6MWT distance was associated with increased odds of moderate or severe complications (adjusted odds ratio, 1.32 per 100 m decrease; 95% confidence interval, 1.01 to 1.73; P = 0.045). There was no association of 6MWT distance with myocardial injury or 30-day death (non-linear association; P = 0.49).
Conclusion: Preoperative 6MWT distance had a modest association with moderate or severe complications after inpatient non-cardiac surgery. Further studies are needed to determine the optimal role of the 6MWT as an objective exercise test for informing preoperative risk stratification.

New Formula to Predict Heart Rate at Anaerobic Threshold That Considers the Effects of β-Blockers in Patients With Myocardial Infarction: MULTI-INSTITUTIONAL RETROSPECTIVE CROSS-SECTIONAL STUDY.

Nemoto S; Kasahara Y; Izawa KP; Watanabe S; Yoshizawa K; Takeichi N; Kamiya K; Suzuki N; Omiya K; Kida K; Matsunaga A; Akashi YJ

Journal of cardiopulmonary rehabilitation and prevention [J Cardiopulm Rehabil Prev] 2021 Apr 16. Date of Electronic Publication: 2021 Apr 16.

Purpose: It is recommended that patients with myocardial infarction (MI) be prescribed exercise by target heart rate (HR) at the anaerobic threshold (AT) via cardiopulmonary exercise testing (CPX). Although percent HR reserve using predicted HRmax (%HRRpred) is used to prescribe exercise if CPX or an exercise test cannot be performed, %HRRpred is especially difficult to use when patients take β-blockers. We devised a new formula to predict HR at AT (HRAT) that considers β-blocker effects in MI patients and validated its accuracy.
Methods: The new formula was created using the data of 196 MI patients in our hospital (derivation sample), and its accuracy was assessed using the data of 71 MI patients in other hospitals (validation sample). All patients underwent CPX 1 mo after MI onset, and resting HR, resting systolic blood pressure (SBP), and HRAT were measured during CPX.
Results: The results of multiple regression analysis in the derivation sample gave the following formula (R2 = 0.605, P < .001): predicted HRAT = 2.035 × (≥65 yr:-1, <65 yr:1) + 3.648 × (body mass index <18.5 kg/m2:-1, body mass index ≥18.5 kg/m2:1) + 4.284 × (β1-blocker(+):-1, β1-blocker(-):1) + 0.734 × (HRrest) + 0.078 × (SBPrest) + 36.812. This formula consists entirely of predictors that can be obtained at rest. HRAT and predicted HRAT with the new formula were not significantly different in the validation sample (mean absolute error: 5.5 ± 4.1 bpm).
Conclusions: The accuracy of the new formula appeared to be favorable. This new formula may be a practical method for exercise prescription in MI patients, regardless of their β-blocker treatment status, if CPX is unavailable.

Neuromuscular efficiency is impaired during exercise in COPD patients.

Frazão M; Santos ADC; Araújo AA; Romualdo MP; de Mello BLC; Jerônimo GG; Paulino FP; Brasileiro-Santos MDS;

Respiratory physiology & neurobiology [Respir Physiol Neurobiol] 2021 Apr 16; Vol. 290, pp. 103673. Date of Electronic Publication: 2021 Apr 16.

Aim: to analyze respiratory and peripheral neuromuscular efficiency during exercise in COPD.
Methods: COPD patients (VEF 1  = 39.25 ± 13.1 %) were paired with healthy subjects. It was performed cardiopulmonary exercise test with simultaneously electromyography (EMG). Respiratory neuromuscular efficiency was determined by relationship between tidal volume and diaphragm EMG. Peripheral neuromuscular efficiency was determined by relationship between power output and vastus lateralis EMG.
Results: Healthy subjects presented higher respiratory neuromuscular efficiency at moderate, heavy and maximum exercise intensities compared to COPD (p < 0.05). Healthy subjects presented higher peripheral neuromuscular efficiency at light, moderate, heavy and maximum exercise intensities compared to COPD (p < 0.001). Dynamic hyperinflation presented correlation with respiratory and peripheral neuromuscular efficiency (r = -0.73 and r = -0.76, p < 0.001).
Conclusion: COPD patients have lower respiratory neuromuscular efficiency at moderate exercise intensity and lower peripheral neuromuscular efficiency at light exercise intensity. Dynamic hyperinflation affects respiratory and peripheral neuromuscular efficiency.

Effects of resistance training on metabolic and cardiovascular responses to a maximal cardiopulmonary exercise test in Parkinson`s disease.

Kanegusuku H; Peçanha T; Silva-Batista C; Miyasato RS; Silva Júnior NDD; Mello MT; Piemonte MEP;
Ugrinowitsch C; Forjaz CLM;

Einstein (Sao Paulo, Brazil) [Einstein (Sao Paulo)] 2021 Apr 19; Vol. 19, pp. eAO5940. Date of Electronic Publication: 2021 Apr 19 (Print Publication: 2021).

Objective: To evaluate the effects of resistance training on metabolic and cardiovascular responses during maximal cardiopulmonary exercise testing in patients with Parkinson’s disease.
Methods: Twenty-four patients with Parkinson’s disease (modified Hoehn and Yahr stages 2 to 3) were randomly assigned to one of two groups: Control or Resistance Training. Patients in the Resistance Training Group completed an exercise program consisting of five resistance exercises (two to four sets of six to 12 repetitions maximum per set) twice a week. Patients in the Control Group maintained their usual lifestyle. Oxygen uptake, systolic blood pressure and heart rate were assessed at rest and during cycle ergometer-based maximal cardiopulmonary exercise testing at baseline and at 12 weeks. Assessments during exercise were conducted at absolute submaximal intensity (slope of the linear regression line between physiological variables and absolute workloads), at relative submaximal intensity (anaerobic threshold and respiratory compensation point) and at maximal intensity (maximal exercise). Muscle strength was also evaluated.
Results: Both groups had similar increase in peak oxygen uptake after 12 weeks of training. Heart rate and systolic blood pressure measured at absolute and relative submaximal intensities and at maximal exercise intensity did not change in any of the groups. Muscle strength increased in the Resistance Training but not in the Control Group after 12 weeks.
Conclusion: Resistance training increases muscle strength but does not change metabolic and cardiovascular responses during maximal cardiopulmonary exercise testing in patients with Parkinson’s disease without cardiovascular comorbidities.

Cardiac Function is Preserved in Adolescents With Well-Controlled Type 1 Diabetes and a Normal Physical Fitness: A Cross-sectional Study.

Van Ryckeghem L;Franssen WMA; Verbaanderd E; Indesteege J; De Vriendt F; Verwerft J;Dendale P; Bito V;
Hansen D;

Canadian journal of diabetes [Can J Diabetes] 2021 Jan 23. Date of Electronic Publication: 2021 Jan 23.

Objectives: Cardiovascular diseases and exercise intolerance elevate mortality in type 1 diabetes (T1D). Left ventricular systolic and diastolic function are already affected in T1DM adolescents, displaying poor glycemic control (glycated hemoglobin [A1C]>7.5%) and exercise intolerance. We investigated to the extent to which left ventricular function is affected by disease severity/duration and whether this is related to exercise capacity.
Methods: Transthoracic echocardiography was performed in 19 T1DM adolescents (14.8±1.9 years old, A1C 7.4±0.9%) and 19 controls (14.4±1.3 years old, A1C 5.3±0.2%), matched for age and Tanner stage. Diastolic and systolic (ejection fraction [EF]) function were assessed. Cardiopulmonary exercise testing was used to evaluate exercise capacity, as measured by peak oxygen uptake (VO 2peak ).
Results: VO 2peak and left ventricular systolic and diastolic function were similar in both groups. Within the T1D group, EF was negatively associated with disease duration (r=-0.79 corrected for age, standardized body mass index, glucose variability and VO 2peak ; p=0.011). Regression analyses revealed that 37.6% of the variance in EF could be attributed to disease duration.
Conclusions: Although left ventricular systolic and diastolic function are preserved in T1D with adequate exercise capacity, disease duration negatively affects EF. The detrimental effects of T1D seem to be driven by disease duration, rather than by disease severity, at least during adolescence. Young T1D patients may, therefore, benefit from cardiovascular evaluation in order to detect cardiovascular abnormalities early in the disease course, and therefore, improve long-term cardiovascular health.

Importance of Cardiopulmonary Exercise Testing amongst Subjects Recovering from COVID-19.

Dorelli G; Braggio M; Gabbiani D; Busti F; Caminati M; Senna G; Girelli D; Laveneziana P; Ferrari M; Sartori G;
Dalle Carbonare L; Crisafulli E;

Diagnostics (Basel, Switzerland) [Diagnostics (Basel)] 2021 Mar 12; Vol. 11 (3). Date of Electronic Publication: 2021 Mar 12.

The cardiopulmonary exercise test (CPET) provides an objective assessment of ventilatory limitation, related to the exercise minute ventilation (V E ) coupled to carbon dioxide output (V CO2 ) (V E /V CO2 ); high values of V E /V CO2 slope define an exercise ventilatory inefficiency (EV in ). In subjects recovered from hospitalised COVID-19, we explored the methodology of CPET in order to evaluate the presence of cardiopulmonary alterations. Our prospective study (RESPICOVID) has been proposed to evaluate pulmonary damage’s clinical impact in post-COVID subjects. In a subgroup of subjects (RESPICOVID2) without baseline confounders, we performed the CPET. According to the V E /V CO2 slope , subjects were divided into having EV in and exercise ventilatory efficiency (EV ef ). Data concerning general variables, hospitalisation, lung function, and gas-analysis were also collected. The RESPICOVID2 enrolled 28 subjects, of whom 8 (29%) had EV in . As compared to subjects with EV ef , subjects with EV in showed a reduction in heart rate (HR) recovery. V E /V CO2 slope was inversely correlated with HR recovery; this correlation was confirmed in a subgroup of older, non-smoking male subjects, regardless of the presence of arterial hypertension. More than one-fourth of subjects recovered from hospitalised COVID-19 have EV in . The relationship between EV in and HR recovery may represent a novel hallmark of post-COVID cardiopulmonary alterations.

Determinants of maximal oxygen uptake in patients with heart failure.

Roibal Pravio J; Barge Caballero E; Barbeito Caamaño C; Paniagua Martin MJ; Barge Caballero G; Couto Mallon D; Pardo Martinez P; Grille Cancela Z; Blanco Canosa P; García Pinilla JM; Vázquez Rodríguez JM; Crespo Leiro MG;

ESC heart failure [ESC Heart Fail] 2021 Mar 27. Date of Electronic Publication: 2021 Mar 27.

Aims: Maximum oxygen uptake (VO 2max ) is an essential parameter to assess functional capacity of patients with heart failure (HF). We aimed to identify clinical factors that determine its value, as they have not been well characterized yet.
Methods: We conducted a retrospective, observational, single-centre study of 362 consecutive patients with HF who underwent cardiopulmonary exercise testing (CPET) as part of standard clinical assessment since 2009-2019. CPET was performed on treadmill, according to Bruce’s protocol (n = 360) or Naughton’s protocol (n = 2). We performed multivariable linear regression analyses in order to identify independent clinical predictors associated with peak VO 2max .
Results: Mean age of study patients was 57.3 ± 10.9 years, mean left ventricular ejection fraction was 32.8 ± 14.2%, and mean VO 2max was 19.8 ± 5.2 mL/kg/min. Eighty-nine (24.6%) patients were women, and 114 (31.5%) had ischaemic heart disease. Multivariable linear regression analysis identified six independent clinical predictors of VO 2max , including NYHA class (B coefficient = -2.585; P < 0.001), age (B coefficient per 1 year = -0.104; P < 0.001), tricuspid annulus plane systolic excursion (B coefficient per 1 mm = +0.209; P < 0.001), body mass index (B coefficient per 1 kg/m 2  = -0.172; P = 0.002), haemoglobin (B coefficient per 1 g/dL = +0.418; P = 0.007) and NT-proBNP (B coefficient per 1000 pg/mL = -0.142; P = 0.019).
Conclusions: The severity of HF (NYHA class, NT-proBNP) as well as age, body composition and haemoglobin levels influence significantly exercise capacity. In patients with HF, the right ventricular systolic function is of greater importance for the physical capacity than the left ventricular systolic function.

Cardiovascular Determinants of Aerobic Exercise Capacity in Adults With Type 2 Diabetes.

Gulsin GS, Henson J, Brady EM, Sargeant JA, Wilmot EG, Athithan L, Htike ZZ, Marsh AM, Biglands JD, Kellman P, Khunti K, Webb D, Davies MJ, Yates T, McCann GP

Diabetes Care. 2020 Sep;43(9):2248-2256. doi: 10.2337/dc20-0706. Epub 2020 Jul 17.

OBJECTIVE: To assess the relationship between subclinical cardiac dysfunction and aerobic exercise capacity (peak VO2) in adults with type 2 diabetes (T2D), a group at high risk of developing heart failure.
RESEARCH DESIGN AND METHODS: Cross-sectional study. We prospectively enrolled a multiethnic cohort of asymptomatic adults with T2D and no history, signs, or symptoms of cardiovascular disease. Age-, sex-, and ethnicity-matched control subjects were recruited for comparison. Participants underwent bioanthropometric profiling, cardiopulmonary exercise testing, and cardiovascular magnetic resonance with adenosine stress perfusion imaging. Multivariable linear regression analysis was undertaken to identify independent associations between measures of cardiovascular structure and function and peak VO2.
RESULTS: A total of 247 adults with T2D (aged 51.8 ± 11.9 years, 55% males, 37% black or south Asian ethnicity, HbA1c 7.4 ± 1.1% [57 ± 12 mmol/mol], and duration of diabetes 61 [32-120] months) and 78 control subjects were included. Subjects with T2D had increased concentric left ventricular remodeling, reduced myocardial perfusion reserve (MPR), and markedly lower aerobic exercise capacity (peak VO2 18.0 ± 6.6 vs. 27.8 ± 9.0 mL/kg/min; P < 0.001) compared with control subjects. In a multivariable linear regression model containing age, sex, ethnicity, smoking status, and systolic blood pressure, only MPR (β = 0.822; P = 0.006) and left ventricular diastolic filling pressure (E/e’) (β = -0.388; P = 0.001) were independently associated with peak VO2 in subjects with T2D. CONCLUSIONS: In a multiethnic cohort of asymptomatic people with T2D, MPR and diastolic function are key determinants of aerobic exercise capacity, independent of age, sex, ethnicity, smoking status, or blood pressure.

Reversal of cardiopulmonary exercise intolerance in patients with post-thrombotic obstruction of the inferior vena cava.

Sebastian T; Barco S; Kreuzpointner R; Konstantinides S; Kucher N;

Thrombosis research [Thromb Res] 2021 Apr 08. Date of Electronic Publication: 2021 Apr 08.

Background: It is unclear whether cardiopulmonary exercise intolerance in patients with chronic obstruction of the inferior vena cava (IVC) is reversible following endovascular IVC reconstruction.
Methods: In 17 patients (mean age 45 ± 15 years, 71% men) with post-thrombotic syndrome due to IVC obstruction and preserved left ventricular ejection fraction (mean 58 ± 3%), we performed cardiopulmonary exercise testing before and 3 months after IVC reconstruction (mean 4.1 ± 1.5 implanted stents). The median time from latest episode of deep vein thrombosis to intervention was 150 (interquartile range 102-820) days.
Results: At baseline, 12 (71%) patients reported New York Heart Association (NYHA) class II or III symptoms, 76% did not achieve >85% of predicted oxygen uptake at peak exercise (mean 61.8 ± 13.7%). After IVC reconstruction, the following changes were observed at anaerobic threshold: work rate increased by 14.6 W, 95%CI (-0.7; 30.0), oxygen uptake increased by 1.8 ml/kg, 95%CI (0.3; 3.3). Oxygen pulse increased by 1.95 ml per beat, 95%CI (1.12; 2.78), corresponding to a mean relative increase of 22.5%, 95%CI (12.4; 32.7) (p < 0.001). The following changes were observed at peak exercise: work rate increased by 48.1 W, 95%CI (27.8; 68.4), oxygen uptake increased by 6.4 ml/kg, 95%CI (3.8; 9.1). Oxygen pulse increased by 2.68 ml per beat, 95%CI (1.60; 3.76), corresponding to a mean relative increase of 29.4%, 95%CI (17.7; 41.2) (p < 0.001). At follow-up, 5 (29%) patients remained in NYHA class II.
Conclusions: In patients with chronic IVC obstruction, cardiopulmonary exercise intolerance as a result of impaired cardiac filling is at least partially reversible following endovascular IVC reconstruction.

Effects of wearing a cloth face mask on performance, physiological and perceptual responses during a graded treadmill running exercise test.

Driver S; Reynolds M; Brown K; Vingren JL; Hill DW; Bennett M; Gilliland T; McShan E; Callender L; Reynolds E; Borunda N;Mosolf J; Cates C; Jones A;

British journal of sports medicine [Br J Sports Med] 2021 Apr 13. Date of Electronic Publication: 2021 Apr 13.

Objectives: To (1) determine if wearing a cloth face mask significantly affected exercise performance and associated physiological responses, and (2) describe perceptual measures of effort and participants’ experiences while wearing a face mask during a maximal treadmill test.
Methods: Randomised controlled trial of healthy adults aged 18-29 years. Participants completed two (with and without a cloth face mask) maximal cardiopulmonary exercise tests (CPETs) on a treadmill following the Bruce protocol. Blood pressure, heart rate, oxygen saturation, exertion and shortness of breath were measured. Descriptive data and physical activity history were collected pretrial; perceptions of wearing face masks and experiential data were gathered immediately following the masked trial.
Results: The final sample included 31 adults (age=23.2±3.1 years; 14 women/17 men). Data indicated that wearing a cloth face mask led to a significant reduction in exercise time (-01:39±01:19 min/sec, p<0.001), maximal oxygen consumption (VO 2 max) (-818±552 mL/min, p<0.001), minute ventilation (-45.2±20.3 L/min), maximal heart rate (-8.4±17.0 beats per minute, p<0.01) and increased dyspnoea (1.7±2.9, p<0.001). Our data also suggest that differences in SpO 2 and rating of perceived exertion existed between the different stages of the CPET as participant’s exercise intensity increased. No significant differences were found between conditions after the 7-minute recovery period.
Conclusion: Cloth face masks led to a 14% reduction in exercise time and 29% decrease in VO 2 max, attributed to perceived discomfort associated with mask-wearing. Compared with no mask, participants reported feeling increasingly short of breath and claustrophobic at higher exercise intensities while wearing a cloth face mask. Coaches, trainers and athletes should consider modifying the frequency, intensity, time and type of exercise when wearing a cloth face mask.