Search

Background: A high minute ventilation/rate of carbon dioxide production (V̇ E /V̇co 2 ) slope during exercise is prognostic for cardiovascular death. Recent data indicate that adults with either controlled or untreated primary hypertension, but not those with uncontrolled hypertension, exhibit a higher V̇ E /V̇co 2 slope during exercise. However, the sample sizes were modest. Therefore, we used the Fitness Registry and the Importance of Exercise National Database to determine whether adults with hypertension, particularly those with controlled or untreated hypertension, exhibit higher V̇ E /V̇co 2 slopes compared with adults without hypertension., Methods and Results: Using the Fitness Registry and the Importance of Exercise National Database, we isolated primary hypertension by excluding those with any disease other than hypertension or taking any medications other than antihypertension medications. We also excluded current smokers and those with obesity. The V̇ E /V̇co 2 slope was determined during a peak cycling exercise test. All data are presented as median [interquartile range]. We compared groups using linear regression adjusted for age, male/female, and body mass index. The characteristics of the entire sample (n=4109) were age, 42 [18] years; 48% women; body mass index, 26 [4] kg/m 2 . The V̇ E /V̇co 2 slope did not differ between adults with hypertension (n=1940; 24.7 [3.7]) compared with those without hypertension (n=2169; 24.9 [3.8]) (hypertension versus no hypertension, P =0.31; overall model: R 2 =0.07, F 4,4104 =73.0; P <0.001). Further, the V̇ E /V̇co 2 slope did not differ between adults with medication-controlled hypertension (n=107; 24.4 [3.0]), untreated hypertension (n=1626; 24.8 [3.9]), uncontrolled hypertension (n=207; 24.8 [3.0]), or those without hypertension (n=2169; 24.9 [3.8]) (hypertension subgroup versus no hypertension, P ≥0.06; overall model: R 2 =0.07, F 6,4102 =49.6, P <0.001)., Conclusions: Primary hypertension is not associated with V̇ E /V̇co 2 slope in the Fitness Registry and the Importance of Exercise National Database.

Background: The US Department of Labor (DOL) does not fund diffusing capacity (D LCO ) or metabolic measurements from cardiopulmonary exercise testing (CPET) for coal miners' disability evaluations. Although exercise arterial blood gas testing is covered, many miners are unable to perform maximal tests, and sampling at peak exercise can be challenging. We explored the relationship between resting D LCO , radiographic disease severity, and CPET abnormalities in former US coal miners., Methods: We analyzed data from miners evaluated between 2005 and 2015. Multivariable linear and logistic regression analyses were used to examine relationships between percent predicted (pp) forced expiratory volume in 1 s (FEV 1 pp), D LCO pp, VO 2 maxpp, A-a oxygen gradient (A-a)pp, dead space fraction (Vd/Vt), disabling oxygen tension (PO 2 ), and radiographic findings of pneumoconiosis., Results: Data from 2015 male coal miners was analyzed. Mean tenure was 28 years (SD 8.6). Thirty-twopercent had an abnormal A-a gradient (>150 pp), 20% had elevated Vd/Vt (>0.33), and 34% a VO 2 max < 60 pp. D LCO pp strongly predicted a disabling PO 2 , with an odds ratio (OR) of 2.33 [2.09-2.60], compared to 1.18 [1.08-1.29] for FEV 1 . Each increase in subcategory of small opacity (simple) pneumoconiosis increased the odds of a disabling PO 2 by 42% [1.29-1.57], controlling for age, body mass index, pack-years of tobacco smoke exposure, and years of coal mine employment., Conclusions: D LCO is the best resting pulmonary function test predictor of CPET abnormalities. Radiographic severity of pneumoconiosis was also associated with CPET abnormalities. These findings support funding D LCO testing for impairment and suggest the term "small opacity" should replace "simple" pneumoconiosis to reflect significant associations with impairment., (© 2024 The Author(s). American Journal of Industrial Medicine published by Wiley Periodicals LLC.)

Background: Established reference standards for the ventilatory threshold (Vt) are lacking. The aim of this study was to develop reference standards for the Vt derived from cardiopulmonary exercise testing (CPX) using treadmill and cycle ergometry.Methods: Seven laboratories experienced in CPX administration with established quality control procedures contributed to the Fitness Registry and the Importance of Exercise: A National Database (FRIEND) from April 2014 through February 2019. Vt data from 27 states in the United States and the Ontario Province in Canada, comprising 9,350 tests (treadmill: n = 1,195; cycle ergometer: n = 8,155) in men (n = 7,540) and women (n = 1,810) 20 to 79 years of age who were free from smoking and known cardiovascular, pulmonary, metabolic, and/or neoplastic disease were used to develop the reference standards. Comparisons of Vt values were made between exercise testing modes, sex, and age groups.Results: Vt values on the treadmill were higher than cycle ergometry; men had higher Vt values than women on both test modalities, and the highest Vt values achieved were in the 20- to 29-year-old age group compared with all other age groups (all P < .001). The rates of decline in Vt values from age groups 20 to 29 through 70 to 79 years of age were 23% and 35% in men and 47% and 30% in women for treadmill and cycle ergometry tests, respectively.Conclusions: In addition to previous reference standards from FRIEND for cardiorespiratory fitness, the Vt reference standards reported herein provide valuable information on functional metric. These data have important implications for CPX interpretation and aerobic exercise prescription in the clinical and fitness settings. [ABSTRACT FROM AUTHOR]

Purpose: Cardiopulmonary exercise testing (CPX) provides valuable clinical information, including peak ventilation (V ˙Epeak), which has been shown to have diagnostic and prognostic value in the assessment of patients with underlying pulmonary disease. This report provides reference standards for V ˙Epeak derived from CPX on treadmills in apparently healthy individuals. Methods: Nine laboratories in the United States experienced in CPX administration with established quality control procedures contributed to the Fitness Registry and the Importance of Exercise National Database from 2014 to 2017. Data from 5232 maximal exercise tests from men and women without cardiovascular or pulmonary disease were used to create percentiles of V ˙Epeak for both men and women by decade between 20 and 79 yr. Additionally, prediction equations were developed for V ˙Epeak using descriptive information. R esults : V ˙Epeak was found to be significantly different between men and women and across age groups (P < 0.05). The rate of decline in V ˙Epeak was 8.0% per decade for both men and women. A stepwise regression model of 70% of the sample revealed that sex, age, and height were significant predictors of V ˙Epeak. The equation was cross-validated with data from the remaining 30% of the sample with a final equation developed from the full sample (r = 0.73). Additionally, a linear regression model revealed forced expiratory volume in 1 s significantly predicted V ˙Epeak (r = 0.73). Conclusions: Reference standards were developed for V ˙Epeak for the United States population. Cardiopulmonary exercise testing laboratories will be able to provide interpretation of V ˙Epeak from these age and sex-specific percentile reference values or alternatively can use these nonexercise prediction equations incorporating sex, age, and height or with a single predictor of forced expiratory volume in 1 s. [ABSTRACT FROM AUTHOR]

Background: Takotsubo cardiomyopathy is an increasingly recognized acute heart failure syndrome precipitated by intense emotional stress. Although there is an apparent rapid and spontaneous recovery of left ventricular ejection fraction, the long-term clinical and functional consequences of takotsubo cardiomyopathy are ill-defined.Methods: In an observational case-control study, we recruited 37 patients with prior (>12-month) takotsubo cardiomyopathy, and 37 age-, sex-, and comorbidity-matched control subjects. Patients completed the Minnesota Living with Heart Failure Questionnaire. All participants underwent detailed clinical phenotypic characterization, including serum biomarker analysis, cardiopulmonary exercise testing, echocardiography, and cardiac magnetic resonance including cardiac 31P-spectroscopy.Results: Participants were predominantly middle-age (64±11 years) women (97%). Although takotsubo cardiomyopathy occurred 20 (range 13-39) months before the study, the majority (88%) of patients had persisting symptoms compatible with heart failure (median of 13 [range 0-76] in the Minnesota Living with Heart Failure Questionnaire) and cardiac limitation on exercise testing (reduced peak oxygen consumption, 24±1.3 versus 31±1.3 mL/kg/min, P<0.001; increased VE/Vco2 slope, 31±1 versus 26±1, P=0.002). Despite normal left ventricular ejection fraction and serum biomarkers, patients with prior takotsubo cardiomyopathy had impaired cardiac deformation indices (reduced apical circumferential strain, -16±1.0 versus -23±1.5%, P<0.001; global longitudinal strain, -17±1 versus -20±1%, P=0.006), increased native T1 mapping values (1264±10 versus 1184±10 ms, P<0.001), and impaired cardiac energetic status (phosphocreatine/γ-adenosine triphosphate ratio, 1.3±0.1 versus 1.9±0.1, P<0.001).Conclusions: In contrast to previous perceptions, takotsubo cardiomyopathy has long-lasting clinical consequences, including demonstrable symptomatic and functional impairment associated with persistent subclinical cardiac dysfunction. Taken together our findings demonstrate that after takotsubo cardiomyopathy, patients develop a persistent, long-term heart failure phenotype.Clinical Trial Registration: URL: https://clinicaltrials.gov. Unique identifier: NCT02989454. [ABSTRACT FROM AUTHOR]

Objective: Response to the coronavirus/COVID-19 pandemic has resulted in several initiatives that directly impact hospital operations. There has been minimal information on how COVID-19 has affected exercise testing in pediatric patients., Design: A web-based survey was designed and sent to pediatric exercise testing laboratories in the United States and Canada. Questions were designed to understand the initial and ongoing adaptations made by pediatric exercise testing laboratories in response to COVID-19. Results were analyzed as frequency data., Results: There were responses from 42% (35/85) of programs, with 68% (23/34) of laboratories discontinuing all exercise testing. Of the 23 programs that discontinued testing, 15 (65%) are actively working on triage plans to reopen the exercise laboratory. Personal protective equipment use include gloves (96%; 25/26), surgical masks (88%; 23/26), N-95 masks (54%; 14/26), face shields (69%; 18/26), and gowns (62%; 16/26). Approximately 47% (15/32) of programs that typically acquire metabolic measurements reported either ceasing or modifying metabolic measurements during COVID-19. Additionally, 62% (16/26) of the programs that previously obtained pulmonary function testing reported either ceasing or modifying pulmonary function testing. Almost 60% of respondents expressed a desire for additional guidance on exercise laboratory management during COVID-19., Conclusions: Pediatric exercise testing laboratories largely closed during the early pandemic, with many of these programs either now open or working on a plan to open. Despite this, there remains heterogeneity in how to minimize exposure risks to patients and staff. Standardization of exercise testing guidelines during the COVID-19 pandemic may help reduce some of these differences.

Purpose: Pectus excavatum (PE) is a chest wall deformity of variable severity and symptomatology. Existing female-specific literature highlights breast asymmetry and cosmetic reconstruction. We sought to evaluate gender differences in cardiopulmonary function., Methods: Cardiac MRIs, pulmonary function tests (PFTs), and cardiopulmonary exercise tests (CPETs) were reviewed in 345 patients undergoing preoperative evaluation for PE. Regression modeling was used to evaluate associations between gender and clinical endpoints of cardiopulmonary function., Results: Mean age was 15.2 years, 19% were female, 98% were white. Pectus indices included median Haller Index (HI) of 4.8, mean depression index (DI) of 0.63, correction index (CI) of 33.6%, and Cardiac Compression Index (CCI) of 2.79. Cardiac assessment revealed decreased right and left ventricular ejection fraction (RVEF, LVEF) in 16% and 22% of patients, respectively. PFTs and CPETs were abnormal in ~ 30% of patients. While females had deeper PE deformities-represented by higher pectus indices-they had superior function with higher RVEF, LVEF Z-scores, FEV 1 , VO 2 max, O 2 pulse, work, and breathing reserve (p < 0.05)., Conclusion: Despite worse PE deformity and symptomatology, females had a better cardiopulmonary function and exercise tolerance than males. Further research is needed to assess the precise mechanisms of this phenomenon and postoperative outcomes in this population.

Background: The relationship between cardiorespiratory fitness (CRF) and mortality risk has typically been assessed using a single measurement, though some evidence suggests the change in CRF over time influences risk. This evidence is predominantly based on studies using estimated CRF (CRF e ). The strength of this relationship using change in directly measured CRF over time in apparently healthy men and women is not well understood., Purpose: To examine the association of change in CRF over time, measured using cardiopulmonary exercise testing (CPX), with all-cause and disease-specific mortality and to compare baseline and subsequent CRF measurements as predictors of all-cause mortality., Methods: Participants included 833 apparently healthy men and women (42.9 ± 10.8 years) who underwent two maximal CPXs, the second CPX being ≥1 year following the baseline assessment (mean 8.6 years, range 1.0 to 40.3 years). Participants were followed for up to 17.7 (SD 11.8) years for all-cause-, cardiovascular disease- (CVD), and cancer mortality. Cox-proportional hazard models were performed to determine the association between the change in CRF, computed as visit 1 (CPX1) peak oxygen consumption (VO 2peak [mL·kg -1 ·min -1 ]) - visit 2 (CPX2) VO 2peak , and mortality outcomes. A Wald-Chi square test of equality was used to compare the strength of CPX1 to CPX2 VO 2peak in predicting mortality., Results: During follow-up, 172 participants died. Overall, the change in CPX-CRF was inversely related to all-cause, CVD, and cancer mortality (p < 0.05). Each 1 mL·kg -1 ·min -1 increase was associated with a ~11, 15, and 16% (all p < 0.001) reduction in all-cause, CVD, and cancer mortality, respectively. The inverse relationship between CRF and all-cause mortality was significant (p < 0.05) when men and women were examined independently, after adjusting for years since first CPX, baseline VO 2peak , and age. Further, the Wald Chi-square test of equality found CPX2 VO 2peak to be a significantly stronger predictor of all-cause mortality than CPX1 VO 2peak (p < 0.05)., Conclusion: The change in CRF over time was inversely related to mortality outcomes, and mortality was better predicted by CRF measured at subsequent test than CPX1 CRF. These findings emphasize the importance of adopting lifestyle behaviors that promote CRF, as well as support the need for routine assessment of CRF in clinical practice to better assess risk., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Objective: This study compared the clinical features, cardiac structure and function evaluated by echocardiography, cardiopulmonary response to exercise and long-term clinical outcomes between patients with heart failure (HF) induced by cancer therapy (CTHF) and heart failure not induced by cancer therapy (NCTHF)., Methods: We evaluated 75 patients with CTHF and 894 with NCTHF who underwent clinically indicated cardiopulmonary exercise testing, and followed these individuals for a median of 4.5 (3.0-5.8) years, during which 187 deaths and 256 composite events (death, heart transplantation and left ventricular (LV) assistant device implantation) occurred., Results: Compared with NCTHF, patients with CTHF were younger, with lower prevalence of cardiovascular comorbidities, higher LV ejection fraction (LVEF), but similar global longitudinal strain. LV diastolic function (higher E/e' ratio) and compliance (higher end-diastolic pressure/LV end-diastolic volume index ratio) were worse in CTHF and were both associated with adverse outcomes. Despite a favourable clinical profile, peak VO 2 and VE/VCO 2 slope were similarly impaired in CTHF and NCTHF. In multivariable Cox regression analysis including clinical characteristics, cardiopulmonary exercise testing variables and LVEF, CTHF was associated with a significantly higher risk of death (HR 2.64; 95% CI 1.53 to 4.55; p=0.001) and composite events (HR 1.79; 95% CI 1.10 to 2.91; p=0.019) compared with NCTHF., Conclusions: CTHF is characterised by a distinct clinical profile, better LVEF but worse LV diastolic properties, and similarly impaired global longitudinal strain, functional capacity and ventilatory efficiency. Accounting for differences in clinical characteristics, CTHF was associated with worse long-term prognosis than NCTHF., Competing Interests: Competing interests: AMS reports receiving research support from Novartis and Bellerophron, and consulting fees from Philips Ultrasound. The other authors have nothing to disclose., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2019. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)