Tremendous Improvement of Cardiovascular Fitness Level in a Patient with Chronic Heart Failure and Severe Impairment of Left Ventricular Systolic Function using Novel Progressive Interval-to- continuous Training on a Treadmill

Moderate-Intensity Continuous Training (MCT) and HighIntensity Interval Training (HIIT) have been widely adopted in cardiac rehabilitation centers. Multiple studies have sought to determine which of these two training models is more effective in improving functional capacity in cardiac patients. Two large trials showed that HIIT was non-inferior to MCT in a cohort of patients with coronary artery disease and chronic heart failure with reduced ejection fraction. However, scarce data are available on the alternative approaches to exercise training. We present a case of significant improvement in cardiovascular fitness level in a patient with chronic heart failure and severe impairment of left ventricular systolic function after two months of exercise training using a customized progressive interval-tocontinuous training model on treadmill, commencing with a moderate-intensity interval approach with further progression to long intervals or steady state exercise following patients’ adaptation.