International Journal of Physical Medicine & Rehabilitation
Open Access

Abstract

Characterization and Functional Implications of Heart Rate Increase and Heart Rate Recovery on Maximal and Submaximal Exercise Capacity in Patients with Advanced Heart Failure

Objective: Heart rate increase early after the initiation of exercise has not been characterized nor related to exercise capacity, heart rate recovery, and gas exchange analyses in patients with advanced heart failure. One hundred and forty-one patients including 121 patients randomized in the GREATER-EARTH trial were investigated.

Methods: Exercise capacity was assessed using a treadmill ramp exercise protocol with gas exchange analyses, a fix-load endurance exercise protocol, and a 6-minute walk test. Heart rate increase was computed at 1-, 2- minutes, and 1/3 of exercise time while heart rate recovery was measured at 1- and 2-minutes following maximal exercise.

Results: Heart rate increase early after the initiation of exercise test was not related to exercise capacity. In contrast, heart rate recovery was significantly related to maximal and submaximal exercise capacity. Among gas exchange responses, only the VE/VCO2 slope and PetCO2 at peak exercise were significantly associated with maximal but not submaximal exercise capacity.

Conclusions: Heart rate increase early after the initiation of exercise yields no relationship with maximal and submaximal exercise capacity in patients with advanced heart failure. Among gas exchange parameters, only some markers of ventilatory inefficiency have significant associations with maximal exercise capacity in patients with heart failure.