Ischaemia is defined as inadequate blood supply or circulation to a local area due to blockage of the blood vessels supplying the area. Ischaemic is when an organ, such as the heart is not getting enough blood and oxygen. Ischaemic heart disease, or known as coronary heart disease (CHD) or coronary artery disease (CAD) are heart problems caused by narrowed coronary arteries that supply blood to the heart muscle.