(N/A) The major disorders of the circulatory system include:
$(1)$ Hypertension: Hypertension is the term for blood pressure that is higher than normal $(120/80 \ mmHg)$. In this measurement,$120 \ mmHg$ is the systolic pressure and $80 \ mmHg$ is the diastolic pressure. If repeated checks of blood pressure of an individual show $140/90 \ mmHg$ or higher,it indicates hypertension. High blood pressure leads to heart diseases and also affects vital organs like the brain and kidneys.
$(2)$ Coronary Artery Disease $(CAD)$: Also referred to as atherosclerosis,it affects the vessels that supply blood to the heart muscle. It is caused by deposits of calcium,fat,cholesterol,and fibrous tissues,which make the lumen of the arteries narrower.
$(3)$ Angina Pectoris: This condition occurs when there is an inadequate supply of oxygen to the heart muscle,resulting in acute chest pain. It can occur in men and women of any age but is more common among middle-aged and elderly people.
$(4)$ Heart Failure: This refers to the state of the heart when it is not pumping blood effectively enough to meet the needs of the body. It is sometimes called congestive heart failure because congestion of the lungs is one of the main symptoms. Heart failure is not the same as cardiac arrest (when the heart stops beating) or a heart attack (when the heart muscle is suddenly damaged by an inadequate blood supply).