Cardiopulmonary Exercise Test in Leukemia Patients After Chemotherapy: A Feasibility Study

To explore the feasibility of cardiopulmonary exercise test (CPET) in leukemia patients after chemotherapy.

Leukemia patients with histologically confirmed hematologic malignancies were reviewed. We evaluated for CPET, between receiving chemotherapy and undergoing stem cell transplantation after 2 weeks. We recorded exercise testing and physiologic parameters during CPET between January 2013 to May 2015. All patients were subjected to symptoms limited to exercise testing, according to the Modified Bruce Protocol. We considered that if respiratory exchange ratio achieved was over 1.10, participants had successfully completed CPET. We dichotomized all participants into two groups (normal group, normal range of resting heart rate; higher group, over 100 per minute of heart rate).

30 patients were finally enrolled. All participants had no adverse effects during the exercise test. Mean peak double product was 26,998.60 mmHg·beats/min (range, 15,481-41,004), and mean peak oxygen consumption (VO₂ peak) was 22.52±4.56 mL/kg/min. Significant differences were observed in the normal group with VO₂ peak (mean, 24.21 mL/kg/min; p=0.027) and number of prior intensive chemotherapy, compared to the higher group (mean, 1.95; p=0.006).

Our results indicate that CPET in leukemia patients before stem cell transplantation was very safe, and is an efficient method to screen for patients with poor cardiac functions. As CPET presents the parameters which reveal the cardiopulmonary functions, including VO₂ peak, double product and exercise capacity, this exercise test would help to predict the physical performance or general condition of the leukemia patients.