Incidence of exercise oscillatory ventilation in a general population at cardiovascular risk : insights from the EURO(pean) EX(ercise) population-based study

Introduction: Among exercise-derived variables that define cardiovascular (CV) risk, oxygen consumption (VO2) is an established one. Gas exchange analysis allows to define ventilator and metabolic parameters that increase the amount of evidence for characterizing the levels of risk. Hypothesis: We aimed at assessing the exercise gas exchange analysis phenotype in the general population at risk for CV disease enrolled in the EUROEX study. Methods: 442 asymptomatic subjects enrolled in the EURO EX trial, (mean age 60±14 years; male 49.3%; BMI 28±5.5 kg/m2) with different CV risk factors (hypertension 66%, dyslipidemia 50.2%, smoking habit 19.2%, diabetes 15.4%) underwent a maximal cardiopulmonary exercise testing with personalized ramp protocol. Results: In this population, 72 subjects (16.3%) exhibited an oscillatory gas exchange pattern as an unexpected finding. Subjects with exercise oscillatory ventilation (EOV) showed a reduced tolerance to exercise (lower peak VO2, % of predicted VO2, peak O2 pulse and delta VO2/delta WR), a worse ventilatory efficiency (steeper VE/VCO2, lower end tidal CO2) and an impaired response of heart rate to maximal exercise and recovery (reduced peak HR and HRR). Conclusions: Our data show for the first time, that EOV, typical of heart failure populations, may also occur in healthy individuals in a meaningful percentage of cases. For the same rate of CV risk factors and demographic characteristics, these patients exhibit a lower performance, a worse ventilatory efficiency and an impaired HR reserve and recovery. These findings may provide the bases for a more in-depth definition of abnormal exercise phenotypes worth of consideration.