Pleural effusion is a lung disease in which fluid accumulates in the pleura, two ballon-like linings which surround and separate the lungs from the heart.
Cardiomyopathy refers to a heart condition or abnormality of the heart which causes inflammation, weakening the heart so it cannot pump blood efficiently.
Acute lymphoblastic leukaemia is the most common childhood cancer. It affects stem cells in bone marrow (lymphoblasts) which mature into blood vessels.