Diseases that affect the heart and cardiovascular system may be due to external factors, such as a bacterial or viral infection, but they are largely due to factors that are the result of human behavior, such as poor diet, lack of exercise, or living under prolonged stress. There are several different categories of diseases that affect the heart and the cardiovascular system. They include the following: coronary heart disease, or CHD; valvular disease, pericarditis, and; arrthymias due to conduction defects. Those that affect the cardiovascular system include systemic hypertension, pulmonary hypertension, and peripheral vascular disease.
Coronary heart disease occurs as the result of any narrowing or blockage of the coronary blood vessels that supply oxygen and nutrients to the cardiac muscle. Elevated blood cholesterol, cigarette smoking, and elevated levels of stress are the most common risk factors. Restricted blood flow to the heart muscle will cause angina, or chest pain. If the coronary vessels become occluded, the result could be a myocardial infarction, or heart attack. In this situation, the muscle deprived of oxygen will die, resulting in permanent heart damage.
Valvular disease can affect any of the four valves in the heart. The one most commonly affected is the mitral, or bicuspid valve, which is located in between the left atrium and left ventricle. It prevents blood from backing up into the left atrium during ventricular contraction. If this valve is diseased, it will result in diminished cardiac function, and could lead to more extensive heart damage. This valve can build up with plaque, which would prevent it from opening and closing properly. This condition is called mitral stenosis. If the tissue that supports the flaps of the valves becomes damaged, the valve flaps can invert, resulting in the condition called mitral valve prolapse.
Pericarditis is an inflammation of the pericardial sac that surrounds the heart. A bacterial or viral infection can cause the sac to fill with fluid, which could inhibit the heart's ability to pump blood effectively.
Conduction defects are caused by any disruption of the conduction of the electrical impulses from the sino-atrial (SA) node, which serves as the pacemaker of the heart; enabling it to beat in a regular pattern. Conduction defects often result from damage to the heart muscle from a myocardial infarction. Malfunctioning of the SA Node, itself, can lead to an irregular heartbeat, or arrythmia. This could be a life-threatening situation.
Systemic hypertension is commonly known as high blood pressure. A diet high in fat and salt, elevated stress levels, obesity, and cigarette smoking are major risk factors for hypertension. If left untreated, the individual has a much greater chance of suffering from strokes or heart attacks. Pulmonary hypertension affects the part of the circulatory system that supplies blood to the lungs. Lung diseases as emphysema and chronic bronchitis are its most likely causes.
Peripheral vascular disease, or PVD affects the blood vessels that supply blood to the extremities; most commonly to the legs. People with inadequately regulated diabetes are at the highest risk for PVD.
These are the major diseases that affect the heart and cardiovascular system. In the majority of cases, they can be prevented with proper diet and exercise, and eliminating cigarette smoking. Advances in medicine enable these diseases to be treated effectively in the majority of cases; either through surgical intervention, or drug administration.