Exercise training (ET) is a Guidelines Class 1A level of evidence adjunct therapy for heart failure (HF) with reduced ejection fraction treatment. As yet less certain is the role of ET for HF with preserved ejection fraction. Different ET types (endurance and resistance) and levels of intensity or domains (light, light-to-moderate and high-to-moderate) are used for ET programmes in patients with cardiac failure. Assessment of ET prescription can be performed through indirect (heart rate reserve) or direct metabolic measures (VO2 reserve, ventilatory threshold) with the most precise methodology based on the analysis of VO2 kinetics during constant work rate protocols of different workloads. The goals of assessing the effects of exercise prescription on functional capacity are traditionally represented by changes in VO2 during peak exercise by cardiopulmonary exercise testing (CPET). Nonetheless, the specific evaluation of how ET may favourably affect the abnormal patterns of VO2 linearity for work rate increase and the effects on ventilation seem important adjunctive parameters to be evaluated and monitored. Although a minority, some HF patients may not respond to ET programmes. This specific phenotype, once appropriately identified, needs a different approach and – intriguingly – should be switched to a higher ET intensity domain to yield the most comprehensive benefits from a personalised ET intervention.
Marco Guazzi - Associate Professor of Cardiology at University of Milan