Cardiopulmonary exercise testing may not predict appropriate implantable cardioverter defibrillator therapies in heart failure patients.

The prognostic value of cardiopulmonary exercise testing (CPET) variables for major cardiovascular events in patients with heart failure (HF) is widely established. However, the prognostic value of these variables as predictors of appropriate implantable cardioverter-defibrillator (ICD) therapies has not been sufficiently well addressed. This study aimed to evaluate CPET variables such as peak oxygen uptake (VO peak), relationship between change in minute ventilation (VE) and carbon dioxide output (VCO) during incremental exercise (VE/VCO slope) and exercise-related periodic breathing (EPB) as appropriate ICD therapy predictors in HF patients.