Ventilatory limitations are not associated with dyspnea on exertion or reduced aerobic fitness in pectus excavatum

Abstract

Exercise intolerance and chest pain are common symptoms in patients with pectus excavatum. To assess if the anatomic extent of pectus deformities determined by the correction index (CI) is associated with a pulmonary impairment at rest and during exercise we performed a retrospective review on pectus patients in our center who completed a symptom questionnaire, cardiopulmonary exercise test (CPET), pulmonary function tests (PFT), and chest magnetic resonance imaging. Of 259 patients studied, dyspnea on exertion and chest pain was reported in 64% and 41%, respectively. Peak oxygen uptake (VO 2 ) was reduced in 30% and classified as mild in two-thirds. A pulmonary limitation during exercise was identified in less than 3%. Ventilatory limitations on PFT was found in 26% and classified as mild in 85%.Obstruction was the most common abnormal pattern (11%). There were no differences between patients with normal or abnormal PFT patterns for the CI, VO 2, or percentage reporting dyspnea or chest pain. Scatter plots demonstrated significant but weak inverse relationships between the CI and lung volumes at rest and during exercise. Multivariable linear regression modeling evaluating predictors of VO 2 demonstrated positive associations with the forced expiratory volume at one second and a negative association with the CI. We conclude that resting PFT patterns have poor correlation with the anatomic extent of the pectus defect, symptomatology or aerobic fitness. Pulmonary limitations on CPET are uncommon and lung volumes during exercise are only minimally associated with the CI.

Long‐term exercise and pulmonary function outcomes in a contemporary cohort of children with congenital diaphragmatic hernia

“…CDH survivors with pectus excavatum had a lower ppFVC, lower ppFEV 1 , and normal ppFEV 1 /FVC compared to those without pectus excavatum. In a recent large retrospective cohort of 256 healthy patients with pectus excavatum, a restrictive pattern was more common, and may explain this finding in our subjects 24 . However, our findings are only suggestive and indicate the need for study in a larger cohort.…”

“…Predicted peak VO 2 was calculated per Wasserman et al and Cooper et al 22,23 Abnormal CPET was defined as percent predicted (pp) peak VO 2 < 80% of predicted normal 14,24 . We further defined exercise limitation as mild, moderate, or severe if pp peak VO 2 were 70%–79.9%, 60%–69.9%, or <60%, respectively 24 . Low oxygen consumption and ventilatory inefficiency (defined as a high minute ventilation/carbon dioxide production slope [VE/VCO 2 slope]) are hallmark CPET features of PH 12,13 .…”

“…A maximum exercise test was defined if 2 of the 3 criteria were met: a respiratory exchange ratio (RER) ≥ 1.1, peak heart rate ≥85% of predicted normal, and/or maximal rating of perceived exertion >18 (normal range: 6–20) 21 . Predicted peak VO 2 was calculated per Wasserman et al and Cooper et al 22,23 Abnormal CPET was defined as percent predicted (pp) peak VO 2 < 80% of predicted normal 14,24 . We further defined exercise limitation as mild, moderate, or severe if pp peak VO 2 were 70%–79.9%, 60%–69.9%, or <60%, respectively 24 .…”

“…14,24 We further defined exercise limitation as mild, moderate, or severe if pp peak VO 2 were 70%-79.9%, 60%-69.9%, or <60%, respectively. 24 Low oxygen consumption and ventilatory inefficiency (defined as a high minute ventilation/carbon dioxide production slope [VE/VCO 2 slope]) are hallmark CPET features of PH. 12,13 We adapted the PH risk stratification guideline cut-offs of pp peak VO 2 < 65% and VE/VCO 2 slope >36 as high risk for PH.…”

Pediatric pulmonology year in review 2021 and 2022: Physiology

“…Declining lung function is a defining characteristic in bronchiolitis obliterans syndrome (BOS), however the clinical implications of lung function changes in BOS are unknown. Jung et al 50 | 2207 into this issue, Hardie et al 51 performed a retrospective review of testing (CPET). Although the majority (64%) of patients reported dyspnea on exertion, pulmonary limitation during exercise was present in only 3% of the study population, and there was no correlation between CPET results and symptoms of dyspnea or chest pain on exertion.…”