Cardiovascular disease (CVD) is the term used to describe atherosclerosis, or hardening of the arteries, as it affects the heart. It is an expression of progressive damage to (or some think natural aging of) the blood vessels that nourish the heart. These blood vessels, or coronary arteries, start off, as do all arteries, with a smooth inner lining. Over time, material becomes imbedded in plaques, or deposits, under the inner lining. This material is a mixture of cholesterol, fatty acids, and scar tissue; ongoing inflammation is an active part of this process.
Cardiovascular disease develops at widely differing rates in different individuals based on a variety of factors. High blood pressure, abnormal blood cholesterol levels (high LDL "bad" cholesterol and/or low HDL "good" cholesterol), smoking, diabetes, male gender, and hereditary factors all independently increase the risk of CVD developing earlier and earlier in life. Other risk factors include high levels of saturated fat and cholesterol intake (whether the blood cholesterol levels are abnormal or not), being overweight, being sedentary, the use of cocaine, and perhaps high levels of other chemicals in the blood, like homocysteine. Each of these factors cause damage to the arterial lining and/or cause plaques to develop more rapidly.
There are direct and indirect effects of CVD. Direct effects include angina pectoris, unstable angina, and myocardial infarction (MI) – a heart attack. Indirect effects include irregular heart rhythms, cardiac arrest, and congestive heart failure.
Angina pectoris results when plaques narrow the diameter of coronary arteries to the extent – usually by 70 percent or more – that the heart becomes significantly deprived of blood during times of exertion. This typically causes chest pressure or pain, though people may experience any of a variety of symptoms, including a sensation of indigestion; dizziness; breathing difficulty; sweatiness; nausea; or pain, pressure, or numbness in the neck, jaw, or arms. Stopping the exertion and placing nitroglycerine under the tongue helps restore the blood flow balance in this situation and the symptoms usually resolve in 5 to10 minutes. This pattern of symptoms is called stable angina.
