Isocapnic buffering: An inconvenient truth about cardiopulmonary exercise testing in heart failure

Relationship Between Respiratory Compensation Point and Anaerobic Threshold in Patients With Heart Failure With Reduced Ejection Fraction

“…Carrie et al performed an insightful clinical and exercise physiology study in which they tested, for the first time, whether the magnitude of increase in V O2 (∆V O2 AT-RCP) within the isocapnic buffering domain can predict syndrome severity and prognosis in patients with HFrEF. 7 However, they found that ∆V O2 AT-RCP was associated with prognosis in the univariate but not the multivariate analysis and concluded that the isocapnic buffering period does stratify with HFrEF but not more than other prognostic indices such as V E/V CO2 slope. 8 Tanehata et al 9 reported a strong correlation between the time between AT and RCP (RCP-AT) and the slope of oxygen uptake as a function of work rate (∆V O2/∆WR).…”