Author Archives: Paul Older

Objective methods for preoperative assessment of functional capacity

  • Silvapulle E; Darvall J;
BJA Education: Review article| Volume 22, ISSUE 8, P312-320, August 01, 2022
By reading this article, you should be able to

  • Describe the three cardiopulmonary variables used most commonly in perioperative medicine: peak oxygen uptake (V˙o2 peak), anaerobic threshold (AT) and ventilatory efficiency (V˙e/V˙co2) at AT.
  • Detail the 6-min walk test (6MWT), incremental shuttle walk test (ISWT) and cardiopulmonary exercise testing (CPET).
  • Analyse the accuracy, applications and limitations of each method.


Inter-observer agreement of preoperative cardiopulmonary exercise test interpretation in major abdominal surgery

R. F. W. Franssen; A. J. J. Eversdijk; M. Kuikhoven; J. M. Klaase; F. J. Vogelaar; M. L. G. Janssen-Heijnen;

BMC Anesthesiol 2022 Vol. 22 Issue 1 Pages 131

BACKGROUND: Accurate determination of cardiopulmonary exercise test (CPET) derived parameters is essential to allow for uniform preoperative risk assessment. The objective of this prospective observational study was to evaluate the inter-observer agreement of preoperative CPET-derived variables by comparing a self-preferred approach with a systematic guideline-based approach.
METHODS: Twenty-six professionals from multiple centers across the Netherlands interpreted 12 preoperative CPETs of patients scheduled for hepatopancreatobiliary surgery. Outcome parameters of interest were oxygen uptake at the ventilatory anaerobic threshold (VO2VAT) and at peak exercise (VO2peak), the slope of the relationship between the minute ventilation and carbon dioxide production (VE/VCO2-slope), and the oxygen uptake efficiency slope (OUES). Inter-observer agreement of the self-preferred approach and the guideline-based approach was quantified by means of the intra-class correlation coefficient.
RESULTS: Across the complete cohort, inter-observer agreement intraclass correlation coefficient (ICC) was 0.76 (95% confidence interval (CI) 0.57-0.93) for VO2VAT, 0.98 (95% CI 0.95-0.99) for VO2peak, and 0.86 (95% CI 0.75-0.95) for the VE/VCO2-slope when using the self-preferred approach. By using a systematic guideline-based approach, ICCs were 0.88 (95% CI 0.74-0.97) for VO2VAT, 0.99 (95% CI 0.99-1.00) for VO2peak, 0.97 (95% CI 0.94-0.99) for the VE/VCO2-slope, and 0.98 (95% CI 0.96-0.99) for the OUES.
CONCLUSIONS: Inter-observer agreement of numerical values of CPET-derived parameters can be improved by using a systematic guideline-based approach. Effort-independent variables such as the VE/VCO2-slope and the OUES might be useful to further improve uniformity in preoperative risk assessment in addition to, or in case VO2VAT and VO2peak are not determinable.

Effectiveness of Perioperative Cardiopulmonary Rehabilitation in Patients With Lung Cancer Undergoing Video-Assisted Thoracic Surgery.

Chao WH; Tuan SH; Tang EK; Tsai YJ; Chung JH; Chen GB; Lin KL;

Frontiers in medicine [Front Med (Lausanne)] 2022 Jun 15; Vol. 9, pp. 900165.
Date of Electronic Publication: 2022 Jun 15 (Print Publication: 2022).

Objectives: Patients with lung cancer pose a high risk of morbidity and mortality after lung resection. Those who receive perioperative cardiopulmonary rehabilitation (PRCR) have better prognosis. Peak oxygen consumption (peak VO 2 ), VO 2 at the ventilatory threshold (VO 2 at VT), and slope of minute ventilation to carbon dioxide production (V E /V CO2 slope) measured during pre-surgical cardiopulmonary exercise testing (CPET) have prognostic values after lung resection. We aimed to investigate the influence of individualized PRCR on postoperative complications in patients undergoing video-assisted thoracic surgery (VATS) for lung cancer with different pre-surgical risks.
Methods: This was a retrospective study. We recruited 125 patients who underwent VATS for lung cancer between 2017 and 2021. CPET was administered before surgery to evaluate the risk level and PRCR was performed based on the individual risk level defined by peak VO2, VO2 at VT, and VE/VCO2 slope, respectively. The primary outcomes were intensive care unit (ICU) and hospital lengths of stay, endotracheal intubation time (ETT), and chest tube insertion time (CTT). The secondary outcomes were postoperative complications (PPCs), including subcutaneous emphysema, pneumothorax, pleural effusion, atelectasis, infection, and empyema.
Results: Three intergroup comparisons based on the risk level by peak VO2 (3 groups), VO2 at VT (2 groups), and VE/VCO2 slope (3 groups) were done. All of the comparisons showed no significant differences in both the primary and secondary outcomes ( p = 0.061-0.910).
Conclusion: Patients with different risk levels showed comparable prognosis and PPCs after undergoing CPET-guided PRCR. PRCR should be encouraged in patients undergoing VATS for lung cancer.

Short- and Long-Term Effects of High-Intensity Interval Training vs. Moderate-Intensity Continuous Training on Left Ventricular Remodeling in Patients Early After ST-Segment Elevation Myocardial Infarction-The HIIT-EARLY Randomized Controlled Trial.

Eser P; Trachsel LD; Marcin T; Herzig D; Freiburghaus I; De Marchi S; Zimmermann AJ; Schmid JP; Wilhelm M;

Frontiers in cardiovascular medicine [Front Cardiovasc Med] 2022 Jun 17; Vol. 9, pp. 869501.
Date of Electronic Publication: 2022 Jun 17 (Print Publication: 2022).

Aim: Due to insufficient evidence on the safety and effectiveness of high-intensity interval training (HIIT) in patients early after ST-segment elevation myocardial infarction (STEMI), we aimed to compare short- and long-term effects of randomized HIIT or moderate-intensity continuous training (MICT) on markers of left ventricular (LV) remodeling in STEMI patients receiving optimal guideline-directed medical therapy (GDMT).
Materials and Methods: Patients after STEMI (<4 weeks) enrolled in a 12-week cardiac rehabilitation (CR) program were recruited for this randomized controlled trial (NCT02627586). During a 3-week run-in period with three weekly MICT sessions, GDMT was up-titrated. Then, the patients were randomized to HIIT or isocaloric MICT for 9 weeks. Echocardiography and cardiopulmonary exercise tests were performed after run-in (3 weeks), end of CR (12 weeks), and at 1-year follow-up. The primary outcome was LV end-diastolic volume index (LVEDVi) at the end of CR. Secondary outcomes were LV global longitudinal strain (GLS) and cardiopulmonary fitness.
Results: Seventy-three male patients were included, with the time between STEMI and start of CR and randomization being 12.5 ± 6.3 and 45.8 ± 10.8 days, respectively. Mixed models revealed no significant group × time interaction for LVEDVi at the end of CR ( p = 0.557). However, there was a significantly smaller improvement in GLS at 1-year follow-up in the HIIT compared to the MICT group ( p = 0.031 for group × time interaction). Cardiorespiratory fitness improved significantly from a median value of 26.5 (1st quartile 24.4; 3rd quartile 1.1) ml/kg/min at randomization in the HIIT and 27.7 (23.9; 31.6) ml/kg/min in the MICT group to 29.6 (25.3; 32.2) and 29.9 (26.1; 34.9) ml/kg/min at the end of CR and to 29.0 (26.6; 33.3) and 30.6 (26.0; 33.8) ml/kg/min at 1 year follow-up in HIIT and MICT patients, respectively, with no significant group × time interactions ( p = 0.138 and 0.317).
Conclusion: In optimally treated patients early after STEMI, HIIT was not different from isocaloric MICT with regard to short-term effects on LVEDVi and cardiorespiratory fitness. The worsening in GLS at 1 year in the HIIT group deserves further investigation, as early HIIT may offset the beneficial effects of GDMT on LV remodeling in the long term.

Myocardial fibrosis in Type 2 Diabetes is associated with functional and metabolomic parameters.

Dennis M; Howpage S; McGill M; Dutta S; Koay Y; Nguyen-Lal L; Lal S; Wu T; Ugander M;Wang A; Munoz PA; Wong J; Constantino MI; O’Sullivan JF; Twigg SM; Puranik R;

International journal of cardiology [Int J Cardiol] 2022 Sep 15; Vol. 363, pp. 179-184.
Date of Electronic Publication: 2022 Jun 18.

Aims: To identify biomarkers of cardiomyopathy in patients with type 2 diabetes mellitus (T2DM) using cardiovascular magnetic resonance (CMR) and to identify associations between functional status, metabolomic profile and myocardial fibrosis.
Methods: In this prospective case control study, patients (n = 49) with T2DM without significant coronary artery disease, and matched controls (n = 18) underwent CMR, cardiopulmonary exercise testing, and plasma metabolomic analyses.
Results: Patients with T2DM (n = 49, median [interquartile range] age 61 [56-63] years, 61% male, diabetes duration 11 [7-20] years), historical HbA1c 7.6% (60 mmol/mol) (6.9-8.6) and matched controls (n = 18) were examined. Study patients had increased myocardial extracellular volume (ECV) (26.9 [23.8-30.0] vs 23.4 [22.4-25.5) %, p < 0.001). Increased ECV was associated with male sex (p = 0.04), time with T2DM (p = 0.02), reduced peak VO 2 (R2 = 0.48, p = 0.01), increased circulating choline (p = 0.002) and cysteamine (p = 0.002) both of which were also associated with reduced peak VO 2 (p < 0.025 and 0.014 respectively).
Conclusions: Patients with well-controlled T2DM without significant coronary disease exhibit focal and diffuse myocardial fibrosis and diffuse myocardial fibrosis is associated with reduced exercise tolerance and metabolites. Plasma metabolites may provide mechanistic insights into diffuse myocardial fibrosis, and cardiopulmonary fitness.


Comparison Between Treadmill and Bicycle Ergometer Exercises in Terms of Safety of Cardiopulmonary Exercise Testing in Patients With Coronary Heart Disease.

Ren C; Zhu J; Shen T; Song Y; Tao L; Xu S; Zhao W; Gao W;

Frontiers in cardiovascular medicine [Front Cardiovasc Med] 2022 Jun 20; Vol. 9, pp. 864637.
Date of Electronic Publication: 2022 Jun 20 (Print Publication: 2022).

Background: Cardiopulmonary exercise testing (CPET) is used widely in the diagnosis, exercise therapy, and prognosis evaluation of patients with coronary heart disease (CHD). The current guideline for CPET does not provide any specific recommendations for cardiovascular (CV) safety on exercise stimulation mode, including bicycle ergometer, treadmill, and total body workout equipment.
Objective: The aim of this study was to explore the effects of different exercise stimulation modes on the occurrence of safety events during CPET in patients with CHD.
Methods: A total of 10,538 CPETs, including 5,674 performed using treadmill exercise and 4,864 performed using bicycle ergometer exercise at Peking University Third Hospital, were analyzed retrospectively. The incidences of CV events and serious adverse events during CPET were compared between the two exercise groups.
Results: Cardiovascular events in enrolled patients occurred during 355 CPETs (3.4%), including 2 cases of adverse events (0.019%), both in the treadmill group. The incidences of overall events [235 (4.1%) vs. 120 (2.5%), P < 0.001], premature ventricular contractions (PVCs) [121 (2.1%) vs. 63 (1.3%), P = 0.001], angina pectoris [45 (0.8%) vs. 5 (0.1%), P < 0.001], and ventricular tachycardia (VT) [32 (0.6%) vs. 14 (0.3%), P = 0.032] were significantly higher in the treadmill group compared with the bicycle ergometer group. No significant difference was observed in the incidence of bradyarrhythmia and atrial arrhythmia between the two groups. Logistic regression analysis showed that the occurrence of overall CV events ( P < 0.001), PVCs ( P = 0.007), angina pectoris ( P < 0.001), and VT ( P = 0.008) was independently associated with the stimulation method of treadmill exercise. In male subjects, the occurrence of overall CV events, PVCs, angina pectoris, and VT were independently associated with treadmill exercise, while only the overall CV events and angina pectoris were independently associated with treadmill exercise in female subjects.
Conclusion: In comparison with treadmill exercise, bicycle ergometer exercise appears to be a safer exercise stimulation mode for CPET in patients with CHD.

Diagnostic tests and subtypes of dysfunctional breathing in children with unexplained exertional dyspnea.

Peiffer C; Pautrat J; Benzouid C; Fuchs-Climent D; Buridans-Travier N; Houdouin V; AP-HP, Bokov P;
NeuroDiderot, Delclaux C;

Pediatric pulmonology [Pediatr Pulmonol] 2022 Jun 30.
Date of Electronic Publication: 2022 Jun 30.

Background: Inappropriate hyperventilation during exercise may be a specific subtype of dysfunctional breathing (DB).
Objective: To assess whether Nijmegen questionnaire and hyperventilation provocation test (HVPT) are able to differentiate inappropriate hyperventilation from other DB subtypes in children with unexplained exertional dyspnea, and normal spirometry and echocardiography.
Methods: The results were compared between a subgroup of 25 children with inappropriate hyperventilation (increased V’E/V’CO 2 slope during a cardiopulmonary exercise test (CPET)) and an age and sex matched subgroup of 25 children with DB without hyperventilation (median age, 13.5 years; 36 girls). Anxiety was evaluated using State-Trait Anxiety Inventory for Children questionnaire.
Results: All children were normocapnic (at rest and peak exercise) and the children with hyperventilation had lower tidal volume/vital capacity on peak exercise (shallow breathing). The Nijmegen score correlated positively with dyspnea during the CPET and the HVPT (p = 0.001 and 0.010, respectively) and with anxiety score (p = 0.022). The proportion of children with a positive Nijmegen score (≥19) did not differ between hyperventilation (13/25) and no hyperventilation (14/25) groups (p = 0.777). Fractional end-tidal CO 2 (FETCO 2 ) at 5-min recovery of the HVPT was < 90% baseline in all children (25/25) of both subgroups. Likewise, there was no significant difference between the two subgroups for other indices of HVPT (FETCO 2 at 3-min recovery and symptoms during the test).
Conclusion: The validity of the Nijmegen questionnaire and the HVPT to discriminate specific subtypes of dysfunctional breathing, as well as the relevance of the inappropriate hyperventilation subtype itself may both be questioned.

Cardiopulmonary exercise testing and impedance cardiography in the assessment of exercise capacity of patients with coronary artery disease early after myocardial revascularization.

Kurpaska M; Krzesiński P; Gielerak G; Gołębiewska K; Piotrowicz K;

BMC sports science, medicine & rehabilitation [BMC Sports Sci Med Rehabil] 2022 Jul 17; Vol. 14 (1), pp. 134.
Date of Electronic Publication: 2022 Jul 17.

Background: Patients with coronary artery disease (CAD) are characterized by different levels of physical capacity, which depends not only on the anatomical advancement of atherosclerosis, but also on the individual cardiovascular hemodynamic response to exercise. The aim of this study was evaluating the relationship between parameters of exercise capacity assessed via cardiopulmonary exercise testing (CPET) and impedance cardiography (ICG) hemodynamics in patients with CAD.
Methods: Exercise capacity was assessed in 54 patients with CAD (41 men, aged 59.5 ± 8.6 years) within 6 weeks after revascularization by means of oxygen uptake (VO 2 ), assessed via CPET, and hemodynamic parameters [heart rate (HR), stroke volume, cardiac output (CO), left cardiac work index (LCWi)], measured by ICG. Correlations between these parameters at anaerobic threshold (AT) and at the peak of exercise as well as their changes (Δpeak-rest, Δpeak-AT) were evaluated.
Results: A large proportion of patients exhibited reduced exercise capacity, with 63% not reaching 80% of predicted peak VO 2 . Clinically relevant correlations were noted between the absolute peak values of VO 2 versus HR, VO 2 versus CO, and VO 2 versus LCWi (R = 0.45, p = 0.0005; R = 0.33, p = 0.015; and R = 0.40, p = 0.003, respectively). There was no correlation between AT VO 2 and hemodynamic parameters at the AT time point. Furthermore ΔVO 2 (peak-AT) correlated with ΔHR (peak-AT), ΔCO (peak-AT) and ΔLCWi (peak-AT) (R = 0.52, p < 0.0001, R = 0.49, p = 0.0001; and R = 0.49, p = 0.0001, respectively). ΔVO 2 (peak-rest) correlated with ΔHR (peak-rest), ΔCO (peak-rest), and ΔLCWi (peak-rest) (R = 0.47, p < 0.0001; R = 0.41, p = 0.002; and R = 0.43, p = 0.001, respectively).
Conclusion: ICG is a reliable method of assessing the cardiovascular response to exercise in patients with CAD. Some ICG parameters show definite correlations with parameters of cardiovascular capacity of proven clinical utility, such as peak VO 2 .

Predictive Ability of Cardiopulmonary Exercise Test Parameters in Heart Failure Patients with Cardiac Resynchronization Therapy.

Reis JF; Gonçalves AV; Brás PG; Moreira RI; Rio P; Timóteo AT; Soares RM; Ferreira RC;

Arquivos brasileiros de cardiologia [Arq Bras Cardiol] 2022 Jul 18.
Date of Electronic Publication: 2022 Jul 18.

Background: There is evidence suggesting that a peak oxygen uptake (pVO2) cut-off of 10ml/kg/min provides a more precise risk stratification in cardiac resynchronization therapy (CRT) patients.
Objective: To compare the prognostic power of several cardiopulmonary exercise testing (CPET) parameters in this population and assess the discriminative ability of the guideline-recommended pVO2cut-off values.
Methods: Prospective evaluation of consecutive heart failure (HF) patients with left ventricular ejection fraction ≤40%. The primary endpoint was a composite of cardiac death and urgent heart transplantation (HT) in the first 24 follow-up months, and was analysed by several CPET parameters for the highest area under the curve (AUC) in the CRT group. A survival analysis was performed to evaluate the risk stratification provided by several different cut-offs. p values <0.05 were considered significant.
Results: A total of 450 HF patients, of which 114 had a CRT device. These patients had a higher baseline risk profile, but there was no difference regarding the primary outcome (13.2% vs 11.6%, p =0.660). End-tidal carbon dioxide pressure at anaerobic threshold (PETCO2AT)had the highest AUC value, which was significantly higher than that of pVO2in the CRT group (0.951 vs 0.778, p =0.046). The currently recommended pVO2cut-off provided accurate risk stratification in this setting (p <0.001), and the suggested cut-off value of 10 ml/min/kg did not improve risk discrimination in device patients (p =0.772).
Conclusion: PETCO2ATmay outperform pVO2’s prognostic power for adverse events in CRT patients. The current guideline-recommended pVO2 cut-off can precisely risk-stratify this population.

Initiation of Dialysis Is Associated With Impaired Cardiovascular Functional Capacity.

Arroyo E;Umukoro PE; Burney HN; Li Y; Li X; Lane KA; Sher SJ; Lu TS; Moe SM; Moorthi R; Coggan AR; McGregor G; Hiemstra TF; Lim K;

Journal of the American Heart Association [J Am Heart Assoc] 2022 Jul 19; Vol. 11 (14), pp. e025656.
Date of Electronic Publication: 2022 Jul 05.

Background The transition to dialysis period carries a substantial increased cardiovascular risk in patients with chronic kidney disease. Despite this, alterations in cardiovascular functional capacity during this transition are largely unknown. The present study therefore sought to assess ventilatory exercise response measures in patients within 1 year of initiating dialysis.
Methods and Results We conducted a cross-sectional study of 241 patients with chronic kidney disease stage 5 from the CAPER (Cardiopulmonary Exercise Testing in Renal Failure) study and from the intradialytic low-frequency electrical muscle stimulation pilot randomized controlled trial cohorts. Patients underwent cardiopulmonary exercise testing and echocardiography. Of the 241 patients (age, 48.9 [15.0] years; 154 [63.9%] men), 42 were predialytic (mean estimated glomerular filtration rate, 14 mL·min -1 ·1.73 m -2 ), 54 had a dialysis vintage ≤12 months, and 145 had a dialysis vintage >12 months. Dialysis vintage ≤12 months exhibited a significantly impaired cardiovascular functional capacity, as assessed by oxygen uptake at peak exercise (18.7 [5.8] mL·min -1 ·kg -1 ) compared with predialysis (22.7 [5.2] mL·min -1 ·kg -1 ; P <0.001). Dialysis vintage ≤12 months also exhibited reduced peak workload, impaired peak heart rate, reduced circulatory power, and increased left ventricular mass index ( P <0.05 for all) compared with predialysis. After excluding those with prior kidney transplant, dialysis vintage >12 months exhibited a lower oxygen uptake at peak exercise (17.0 [4.9] mL·min -1 ·kg -1 ) compared with dialysis vintage ≤12 months (18.9 [5.9] mL·min -1 ·kg -1 ; P =0.033).
Conclusions Initiating dialysis is associated with a significant impairment in oxygen uptake at peak exercise and overall decrements in ventilatory and hemodynamic exercise responses that predispose patients to functional dependence. The magnitude of these changes is comparable to the differences between low-risk New York Heart Association class I and higher-risk New York Heart Association class II to IV heart failure.