Clinical Research Directory

Inclusion Criteria: * Cases: * Acute lymphoblastic leukemia survivor, OR living with chronic lung disease of prematurity, OR living with heart transplant * 8-25 years old * Height: ≥ 48 inches * Ambulatory without assistance * English speaking * Normotensive (\<95th percentile for age; okay if managed with antihypertensive medication) * SpO2 \>92% * Not pregnant * ALL survivor specific: must have completed therapy ≥ 3 months prior to study entry * Controls * 8-25 years old * Height: ≥ 48 inches * Ambulatory without assistance * English speaking * No history of arrhythmia or known cardiac dysfunction at baseline * Normotensive (\<95th percentile for age; okay if managed with antihypertensive medication) * SpO2 \>95% * Not pregnant Exclusion Criteria: * Cases: * ALL specific: received cranial radiation, bone marrow transplant recipients * Investigator or patient's primary physician deems the patient unsuitable for the study * Controls: * History of malignancy, CLD or HT or any other diagnosis which may reduce cardiorespiratory function * Investigator deems the patient unsuitable for the study