The objective of this phase 3 clinical trial, presented by Christina Chrysohoou, MD, PhD, University of Athens, Athens, Greece, was to evaluate the effect of a high-intensity interval exercise program on left ventricular (LV) function and systemic arterial stiffness in patients with congestive heart failure (CHF) [Chrysohoou C et al. Int J Cardiol. 2015].

The inclusion criteria included NYHA class II to IV and ejection fraction < 30%. Patients were randomized 1:1 to the exercise arm (n = 50) or the control arm (n = 50). Patients in the exercise arm underwent an exercise session 3 days per week for a total of 12 weeks. Each session consisted of high-intensity interval ergometric aerobic cycles of 30 seconds at 100% of maximum workload followed by 30 seconds of rest for a duration of 30 minutes. The control group received routine CHF care.

Patients were assessed with a cardiopulmonary stress test, noninvasive high-fidelity tonometry of the radial artery, pulse-wave velocity measurement, and echocardiography before and after completion of the training program. Maximal oxygen uptake and maximum carbon dioxide production were measured breath by breath, before and after the exercise training. The primary end points of the trial were quality of life (QoL), LV diastolic function, and aortic elastic properties at 12 weeks.

Among the 50 patients originally randomized to each arm, 33 in the exercise arm and 39 in the control arm completed the trial. The patients in the exercise training arm were aged 63 ± 9 years and 88% were men. The patients in the control arm were aged 56 ± 11 years and 82% were men. Seventy percent of the patients in both arms had ischemic heart failure. No statistical differences in baseline physical activity status (evaluated by the International Physical Activity Questionnaire), body mass index, smoking habits, history of hypertension, diabetes, or dyslipidemia were found. Data were evaluated using an intention-to-treat analysis.

In the exercise arm, a general mixed-effects model demonstrated reductions from baseline to 12 weeks in a variety of measurements (Table 1).

No significant changes from baseline were observed in any of the parameters in the control group. The investigators concluded that high-intensity interval aerobic training, combined with strength exercise, may benefit aortic dilatation capacity, augment systolic pressure, and improve LV diastolic function and QoL.