Author Archives: Paul Older

Protective Effects of BNT162b2 Vaccination on Aerobic Capacity Following Mild to Moderate SARS-CoV-2 Infection: A Cross-Sectional Study Israel.

Blumberg Y; Edelstein M; Abu Jabal K; Golan R; Tuvia N; Perets Y; Saad M; Levinas T; Saleem DIsraeli Z; Alaa AR; Elbaz Greener G; Amital A; Halabi M;

Journal of clinical medicine [J Clin Med] 2022 Jul 29; Vol. 11 (15).
Date of Electronic Publication: 2022 Jul 29.

Patients previously infected with acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may experience post-acute adverse health outcomes, known as long COVID. The most reported symptoms are fatigue, headache and attention/concentration issues, dyspnea and myalgia. In addition, reduced aerobic capacity has been demonstrated in both mild and moderate COVID-19 patients. It is unknown whether COVID-19 vaccination mitigates against reduced aerobic capacity. Our aim was to compare the aerobic capacity of vaccinated and unvaccinated individuals previously infected with SARS-CoV-2.
Methods: Individuals aged 18 to 65 years with laboratory-confirmed mild to moderate COVID-19 disease were invited to Ziv Medical Centre, Israel, three months after SARS-CoV-2 infection. We compared individuals unvaccinated at the time of infection to those vaccinated in terms of aerobic capacity, measured using symptom-limited cardiopulmonary exercise test (CPET).
Results: We recruited 28 unvaccinated and 22 vaccinated patients. There were no differences in baseline demographic and pulmonary function testing (PFT) parameters. Compared with unvaccinated individuals, those vaccinated had higher V’O 2 /kg at peak exercise and at the anaerobic threshold. The V’O 2 /kg peak in the unvaccinated group was 83% of predicted vs. 100% in the vaccinated ( p < 0.002). At the anaerobic threshold (AT), vaccinated individuals had a higher V’O 2 /kg than those unvaccinated.
Conclusions: Vaccinated individuals had significantly better exercise performance. Compared with vaccinated individuals, a higher proportion of those unvaccinated performed substantially worse than expected on CPET. These results suggest that vaccination at the time of infection is associated with better aerobic capacity following SARS-CoV-2 infection.

Physiological Predictors of Morbidity and Mortality in COPD: The Relative Importance of Reduced Inspiratory Capacity and Inspiratory Muscle Strength.

Phillips DB; James MD;O’Donnell CJD; Vincent SG; Webb KA; de-Torres JP; Neder JA; O’Donnell DE;

Journal of applied physiology (Bethesda, Md. : 1985) [J Appl Physiol (1985)] 2022 Aug 11.
Date of Electronic Publication: 2022 Aug 11.

Low resting inspiratory capacity (IC) and low maximal inspiratory pressure (MIP) have previously been linked to exertional dyspnea, exercise limitation and poor survival in chronic obstructive pulmonary disease (COPD). The interaction and relative contributions of these two related variables to important clinical outcomes are unknown. The objective of the current study was to examine the interaction between resting IC and MIP (both % predicted), exertional dyspnea, exercise capacity and long-term survival in patients with COPD. Two hundred and eighty-five patients with mild to advanced COPD completed standard lung function testing and a cycle cardiopulmonary exercise test. Multiple regression determined predictors of the exertional dyspnea-ventilation slope and peak oxygen uptake (V̇O 2peak ). Cox regression determined predictors of 10-year mortality. IC was associated with the dyspnea-ventilation slope (standardized β=-0.44, p<0.001), while MIP was excluded from the regression model (p=0.713). IC and MIP were included in the final model to predict V̇O 2peak . However, the standardized β was greater for IC (0.49) than MIP (0.22). After adjusting for age, sex, body mass index, cardiovascular risk, airflow obstruction and diffusing capacity, resting IC was independently associated with 10-year all-cause mortality (hazard ratio=1.25, confidence interval 5-95% =1.16-1.34, p<0.001), while MIP was excluded from the final model (all p=0.829). Low resting IC was consistently linked to heightened dyspnea intensity, low V̇O 2peak and worse survival in COPD even after accounting for airway obstruction, inspiratory muscle strength, and diffusing capacity. These results support the use of resting IC as an important physiological biomarker closely linked to key clinical outcomes in COPD.

Ventilatory efficiency is superior to peak oxygen uptake for prediction of lung resection cardiovascular complications.

Mazur A; Brat K; Homolka P; Merta Z; Svoboda M; Bratova M; Sramek V; Republic.; Olson LJ; Cundrle I;

PloS one [PLoS One] 2022 Aug 12; Vol. 17 (8), pp. e0272984.
Date of Electronic Publication: 2022 Aug 12 (Print Publication: 2022).

Introduction: Ventilatory efficiency (VE/VCO2 slope) has been shown superior to peak oxygen consumption (VO2) for prediction of post-operative pulmonary complications in patients undergoing thoracotomy. VE/VCO2 slope is determined by ventilatory drive and ventilation/perfusion mismatch whereas VO2 is related to cardiac output and arteriovenous oxygen difference. We hypothesized pre-operative VO2 predicts post-operative cardiovascular complications in patients undergoing lung resection.
Methods: Lung resection candidates from a published study were evaluated by post-hoc analysis. All of the patients underwent preoperative cardiopulmonary exercise testing. Post-operative cardiovascular complications were assessed during the first 30 post-operative days or hospital stay. One-way analysis of variance or the Kruskal-Wallis test, and multivariate logistic regression were used for statistical analysis and data summarized as median (IQR).
Results: Of 353 subjects, 30 (9%) developed pulmonary complications only (excluded from further analysis), while 78 subjects (22%) developed cardiovascular complications and were divided into two groups for analysis: cardiovascular only (n = 49) and cardiovascular with pulmonary complications (n = 29). Compared to patients without complications (n = 245), peak VO2 was significantly lower in the cardiovascular with pulmonary complications group [19.9 ml/kg/min (16.5-25) vs. 16.3 ml/kg/min (15-20.3); P<0.01] but not in the cardiovascular only complications group [19.9 ml/kg/min (16.5-25) vs 19.0 ml/kg/min (16-23.1); P = 0.18]. In contrast, VE/VCO2 slope was significantly higher in both cardiovascular only [29 (25-33) vs. 31 (27-37); P = 0.05] and cardiovascular with pulmonary complication groups [29 (25-33) vs. 37 (34-42); P<0.01)]. Logistic regression analysis showed VE/VCO2 slope [OR = 1.06; 95%CI (1.01-1.11); P = 0.01; AUC = 0.74], but not peak VO2 to be independently associated with post-operative cardiovascular complications.
Conclusion: VE/VCO2 slope is superior to peak VO2 for prediction of post-operative cardiovascular complications in lung resection candidates.

Functional Capacity and Quality of Life in Patients With Vascular Ring.

Nir V; Bentur L; Zucker-Toledano M; Gur M; Adler Z; Hanna M; Toukan Y; Masarweh K; Hakim F; Bar-Yoseph R

Pediatric pulmonology [Pediatr Pulmonol] 2022 Aug 15.
Date of Electronic Publication: 2022 Aug 15.

Background: Vascular rings are congenital anomalies of the aortic arch that compress the trachea and esophagus and may require corrective surgery. Data about the long-term effects of vascular rings are scarce. We aimed to evaluate the long-term cardiorespiratory, exercise capacity and quality of life of vascular ring patients.
Methods: A single center prospective study evaluating spirometry, echocardiography, six-minute walk test (6MWT), cardiopulmonary exercise testing (CPET) and quality of life questionnaire (SF36) in patients with a diagnosis of vascular ring, with or without corrective surgery.
Results: Twenty-seven patients participated (11.9±6 years, 52% males). The most common diagnosis was double aortic arch (16 patients, 59%). Nineteen patients had corrective surgery (O) and eight did not (NO). Pulmonary function tests were within normal range in both groups (FEV 1 % predicted O=87.6±16.5, NO=83±10.8%). However, 11/27 had abnormal FEV 1 , five had abnormal FVC and 13 (48%) had flattening of the expiratory curve. 6MWD and oxygen uptake were similarly mildly reduced in both groups; (6MWD O=80.1±10.7% predicted, NO=74.1±10.9% and oxygen uptake O=78.5±23.2% predicted, NO=73.4±14.3%). Peak O 2 pulse (V̇O 2 /HR% predicted) was mildly reduced in the NO group (O=88.4±17.3%, NO=75.8±16.2%). Echocardiogram and SF36 scores were normal in all patients.
Conclusions: Long-term evaluation of patients born with vascular rings revealed mild pulmonary impairment, reduction in 6MWD and oxygen uptake. The NO group had also mild reduced peak O 2 pulse. Larger, long-term studies assessing functional parameters in operated and non-operated patients are needed to assess disease/surgery limitation in patients with vascular rings.

Exercise Intolerance in Post-Acute Sequelae of COVID-19 and the Value of Cardiopulmonary Exercise Testing- a Mini-Review.

Aparisi Á; Ladrón R;Ybarra-Falcón C; Tobar J; San Román JA;

Frontiers in medicine [Front Med (Lausanne)] 2022 Jul 22; Vol. 9, pp. 924819.
Date of Electronic Publication: 2022 Jul 22 (Print Publication: 2022).

Coronavirus disease (COVID-19) is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with systemic organ damage in the most severe forms. Long-term complications of SARS-CoV-2 appear to be restricted to severe presentations of COVID-19, but many patients with persistent symptoms have never been hospitalized. Post-acute sequelae of COVID-19 (PASC) represents a heterogeneous group of symptoms characterized by cardiovascular, general, respiratory, and neuropsychiatric sequelae. The pace of evidence acquisition with PASC has been rapid, but the mechanisms behind it are complex and not yet fully understood. In particular, exercise intolerance shares some features with other classic respiratory and cardiac disorders. However, cardiopulmonary exercise testing (CPET) provides a comprehensive assessment and can unmask the pathophysiological mechanism behind exercise intolerance in gray-zone PASC. This mini-review explores the utility of CPET and aims to provide a comprehensive assessment of PASC by summarizing the current evidence.

Percentage of Age-Predicted Cardiorespiratory Fitness May Be a Stronger Risk Indicator for Incident Type 2 Diabetes Than Absolute Levels of Cardiorespiratory Fitness.

Kunutsor SK; Khan H; Seidu S; Laukkanen JA

Journal of cardiopulmonary rehabilitation and prevention [J Cardiopulm Rehabil Prev] 2022 Aug 04.
Date of Electronic Publication: 2022 Aug 04.

Purpose: There are inverse and independent associations between cardiorespiratory fitness (CRF) and several adverse cardiometabolic outcomes. The percentage of age-predicted CRF (%age-predicted CRF) is comparable to absolute CRF as a risk indicator for some of these outcomes, but the association between %age-predicted CRF and risk of type 2 diabetes (T2D) has not been previously investigated. We aimed to assess the association between %age-predicted CRF and T2D in a prospective cohort study.
Methods: Cardiorespiratory fitness, as measured directly by peak oxygen uptake, was assessed in 1901 men aged 42-60 yr who underwent cardiopulmonary exercise testing. The age-predicted CRF estimated from a regression equation for age was converted to %age-predicted CRF using (achieved CRF/age-predicted CRF) × 100. Hazard ratios (95% CI) were estimated for T2D.
Results: During a median follow-up of 26.8 yr, 227 T2D cases were recorded. The risk of T2D decreased continuously with increasing %age-predicted CRF (P value for nonlinearity = .30). A 1-SD increase in %age-predicted CRF was associated with a decreased risk of T2D in analysis adjusted for established risk factors (HR = 0.68: 95% CI, 0.59-0.79). The corresponding adjusted risk was (HR = 0.51: 95% CI, 0.35-0.75) comparing extreme tertiles of %age-predicted CRF. The respective estimates for the association between absolute CRF and T2D were-HR (95% CI)-0.71 (0.60-0.83) and 0.64 (0.44-0.95).
Conclusions: Percentage of age-predicted CRF is linearly, inversely, and independently associated with the risk of incident T2D and may be a stronger risk indicator for T2D compared to absolute CRF in a general population of middle-aged and older men.

Early flattening of the oxygen pulse during the cardiopulmonary exercise test in asymptomatic adults and its association with cardiovascular risk factors.

de Almeida VR; di Paschoale Ostolin TLV; de Barros Gonze B; de Almeida FR; Romiti M; Arantes RL; Dourado VZ;

International journal of cardiology [Int J Cardiol] 2022 Aug 06.
Date of Electronic Publication: 2022 Aug 06.

Background: Individuals with cardiovascular exercise limitations present oxygen pulse morphology with early flattening (plateau) during the cardiopulmonary exercise test (CPET). Although this oxygen pulse response is well known in cardiac patients, these changes’ prevalence and clinical relevance in asymptomatic individuals are not known. We aimed to quantify the proportion of asymptomatic adults with an early flattening of the oxygen pulse and investigate its association with classical cardiovascular risk factors.
Methods: We carried out a cross-sectional study with a sample of 824 adults aged between 18 and 80 years. We assessed anthropometry, body composition, and cardiovascular risk. In addition, we obtained cardiorespiratory and metabolic responses during a ramp protocol treadmill CPET.
Results: The prevalence of early flattening of the oxygen pulse was 36.8%. These participants were predominantly females, older, less educated, with a higher body mass and percentage of fat and a lower percentage of lean body mass. After a multinominal multiple logistic regression analysis, we identified female sex (odds ratio, 5.46: 95% confidence interval, 3.73-7.99), low education (2.24: 1.47-3.42), dyslipidemia (1.67: 1.14-2.45), smoking (1.64: 1.00-2.69), and physical inactivity (1.39: 1.02-1.96) as the leading independent predictors of the early flattening of oxygen pulse.
Conclusion: The early flattening of oxygen pulse is common in asymptomatic adults and is highly determined by modifiable cardiovascular risk factors. These results suggest that identifying the early flattening of oxygen pulse may be helpful in the prevention of cardiovascular diseases.

Systolic Blood Pressure Response to Exercise in Endurance Athletes in Relation to Oxygen Uptake, Work Rate and Normative Values

Carlen A; Eklund G; Andersson A; Carlhall C: Ekstrom M; Hedman K

Journal of Cardiovascular Development and Disease: Volume 9. Issue 7. 2022

Work rate has a direct impact on the systolic blood pressure (SBP) during aerobic exercise, which may be challenging in the evaluation of the SBP response in athletes reaching high work rates. We aimed to investigate the exercise SBP response in endurance athletes in relation to oxygen uptake (VO2), work rate and to recent reference equations for exercise SBP in the general population. Endurance athletes with a left-ventricular end-diastolic diameter above the reference one performed a maximal bicycle cardiopulmonary exercise test. The increase in SBP during exercise was divided by the increase in VO2 (SBP/VO2 slope) and in Watts, respectively (SBP/W slope). The maximum SBP (SBPmax) and the SBP/W slope were compared to the predicted values. In total, 27 athletes (59% men) were included; mean age, 40 ± 10 years; mean VO2max, 50 ± 5 mL/kg/min. The mean SBP/VO2 slope was 29.8 ± 10.2 mm Hg/L/min, and the mean SBP/W slope was 0.27 ± 0.08 mm Hg/W. Compared to the predicted normative values, athletes had, on average, a 12.2 ± 17.6 mm Hg higher SBPmax and a 0.12 ± 0.08 mm Hg/W less steep SBP/W slope (p < 0.01 and p < 0.001, respectively). In conclusion, the higher SBPmax values and the less steep SBP/W slope highlight the importance of considering work rate when interpreting the SBP response in endurance athletes and suggest a need for specific normative values in athletes to help clinicians distinguish physiologically high maximal blood pressure from a pathological blood pressure response.

 

Ventilatory efficiency in combination with peak oxygen uptake improves risk stratification in patients undergoing lobectomy

Hedman K; Hylander J; Mikios B; Fyrenius A

Journal of Thoracic & Cardiovascular Surgery: July 1 2022

Objective
We aimed to evaluate whether or not using the slope of the increase in minute ventilation in relation to carbon dioxide (VE/VCo2-slope), with a cutoff value of 35, could improve risk stratification for major pulmonary complications or death following lobectomy in lung cancer patients at moderate risk (Vo2peak = 10-20 mL/kg/min).
Methods
Single center, retrospective analysis of 146 patients with lung cancer who underwent lobectomy and preoperative cardiopulmonary exercise testing in 2008-2020. The main outcome was any major pulmonary complication or death within 30 days of surgery. Patients were categorized based on their preoperative cardiopulmonary exercise testing as: low-risk group, peak oxygen uptake >20 mL/kg/min; low-moderate risk, peak oxygen uptake 10 to 20 mL/kg/min and VE/VCo2-slope <35; and moderate-high risk, peak oxygen uptake 10 to 20 mL/kg/min and VE/VCo2-slope ≥35. The frequency of complications between groups was compared using χ2 test. Logistic regression was used to calculate the odds ratio with 95% CI for the main outcome based on the cardiopulmonary exercise testing group.
Results
Overall, 25 patients (17%) experienced a major pulmonary complication or died (2 deaths). The frequency of complications differed between the cardiopulmonary exercise testing groups: 29%, 13%, and 8% in the moderate-high, low-moderate, and low-risk group, respectively (P = .023). Using the low-risk group as reference, the adjusted odds ratio for the low-moderate risk group was 3.44 (95% CI, 0.66-17.90), whereas the odds ratio for the moderate-high risk group was 8.87 (95% CI, 1.86-42.39).
Conclusions
Using the VE/VCo2-slope with a cutoff value of 35 improved risk stratification for major pulmonary complications following lobectomy in lung cancer patients with moderate risk based on a peak oxygen uptake of 10 to 20 mL/kg/min. This suggests that the VE/VCo2-slope can be used for preoperative risk evaluation in lung cancer lobectomy.

 

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.