Cardiopulmonary exercise testing for identification of patients with hyperventilation syndrome

Introduction: Measurement of ventilatory efficiency for carbon dioxide (VE/VCO2) by cardiopulmonary exercise testing (CPET) has been proposed as a screening method for identification of patients with hyperventilation syndrome (HVS). However, increased VE/VCO2 may be associated with other disorders. Aims: We aimed at finding a more specific marker of HVS by CPET. We hypothesized that ventilatory control during exercise is abnormal in patients with HVS. Methods: HVS patients who underwent CPET at the Department of Respiratory Diseases, University Hospital Brno, Czech Rep. between 2015, Jan 1st and 2017, Dec 31st were retrospectively identified and formed the study group. HVS was defined as dyspnea with respiratory alkalosis (pH >7.45) at peak exercise with absence of acute or chronic respiratory, heart or psychiatric disease. Healthy subjects were selected as controls. Student t-test and Mann-Whitney U test were used for comparison; data are summarized as mean ± SD or median (IQR); significance level: p Results: We identified 29 HVS patients and selected 29 controls. At rest, mean PETCO2 was 27 mmHg for HVS patients vs. 30 mmHg in controls (p=0.05). At peak exercise, PETCO2 was also significantly lower (27 mmHg vs. 35 mmHg; p Conclusion: Absence of VE/VCO2 and PETCO2 change during exercise may identify patients with HVS.