<b>Background:</b> Ventilatory control instability is common in patients with heart failure (HF) and can manifest as exercise oscillatory ventilation (EOV) characterized by a crescendo-decrescendo breathing pattern. Oxygen consumption (VO2), the anaerobic threshold (VO2AT) and ventilation efficiency (VE/VCO2) help to quantify severity and predict survival of patients with HF. Recently it has been shown that EOV is related with less aerobic capacity and impaired ventilatory efficiency. <b>Methods:</b> We reviewed the charts of patients of HF with a cardiopulmonary exercise test (CPET) as part of a heart transplant evaluation (2014-2015) in a cardiac/pulmonary reference center in Bogota, Colombia. <b>Results:</b> Of the 49 patients, 24 (49%) had EOV and presented lower LVEF (p=0.025), reduced workload (p=0.013), lower peak VO2 (p=0.015), lower oxygen pulse (VO2/FC) (p=0.008), early anaerobic threshold (AT) (p=0.040), increased dead space (Vd/Vt) at rest (p=0.016) and at exercise (p=0.014) and increased end tidal CO2 arterial difference (p=0.037). There was no significant difference in VE/VCO2 AT, which for both groups was normal for the altitude of 2640 mts. <b>Conclusion:</b> The results of the study corroborate the findings that patients who exhibit a pattern of EOV have reduced aerobic capacity determined by the VO2, early anaerobic threshold and reduced work capacity; and lower ventilatory efficiency determined by increased dead space at rest and exercise and increased end tidal CO2 arterial difference. In HF patients, EOV emerges as a key prognostic parameter as indicates general deterioration of other CPET derived prognostic values.