Overshoot of the Respiratory Exchange Ratio during Recovery from Maximal Exercise Testing in Young Patients with Congenital Heart Disease

Marco Vecchiato; Andrea Ermolao; Emanuele Zanardo; Francesca Battista; Giacomo Ruvoletto; Stefano Palermi; Giulia Quinto; Gino Degano; Andrea Gasperetti; Massimo A Padalino; Giovanni Di Salvo; Daniel Neunhaeuserer

doi:10.3390/children10030521

Overshoot of the Respiratory Exchange Ratio during Recovery from Maximal Exercise Testing in Young Patients with Congenital Heart Disease

Children (Basel). 2023 Mar 7;10(3):521. doi: 10.3390/children10030521.

Authors

Marco Vecchiato^{1

2}, Andrea Ermolao^{1

2}, Emanuele Zanardo^{1

2}, Francesca Battista^{1

2}, Giacomo Ruvoletto¹, Stefano Palermi³, Giulia Quinto^{1

2}, Gino Degano^{1

2}, Andrea Gasperetti^{1

2}, Massimo A Padalino⁴, Giovanni Di Salvo⁵, Daniel Neunhaeuserer^{1

2}

Affiliations

¹ Sports and Exercise Medicine Division, Department of Medicine, University of Padova, 35128 Padova, Italy.
² Clinical Network of Sports and Exercise Medicine of the Veneto Region, 35131 Padova, Italy.
³ Public Health Department, University of Naples Federico II, 80131 Naples, Italy.
⁴ Pediatric and Congenital Cardiac Surgery Unit, Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University of Padova, 35128 Padova, Italy.
⁵ Pediatric and Congenital Cardiology Unit, Department for Women's and Children's Health, University of Padova, 35128 Padova, Italy.

Abstract

Introduction: The overshoot of the respiratory exchange ratio (RER) after exercise is reduced in patients with heart failure.

Aim: The present study aimed to investigate the presence of this phenomenon in young patients with congenital heart disease (CHD), who generally present reduced cardiorespiratory fitness.

Methods: In this retrospective study, patients with CHD underwent a maximal cardiopulmonary exercise testing (CPET) assessing the RER recovery parameters: the RER at peak exercise, the maximum RER value reached during recovery, the magnitude of the RER overshoot and the linear slope of the RER increase after the end of the exercise.

Results: In total, 117 patients were included in this study. Of these, there were 24 healthy age-matched control subjects and 93 young patients with CHD (transposition of great arteries, Fontan procedure, aortic coarctation and tetralogy of Fallot). All patients presented a RER overshoot during recovery. Patients with CHD showed reduced aerobic capacity and cardiorespiratory efficiency during exercise, as well as a lower RER overshoot when compared to controls. RER magnitude was higher in the controls and patients with aortic coarctation when compared to those with transposition of great arteries, previous Fontan procedure, and tetralogy of Fallot. The RER magnitude was found to be correlated with the most relevant cardiorespiratory fitness and efficiency indices.

Conclusions: The present study proposes new recovery indices for functional evaluation in patients with CHD. Thus, the RER recovery overshoots analysis should be part of routine CPET evaluation to further improve prognostic risk stratifications in patients with CHD.

Keywords: CHD; Fallot; Fontan; RER; cardiopulmonary exercise test; coarctation; functional evaluation; transposition.

Grants and funding

This research received no external funding.