|
|
|
|
Heart Disease - Description What is CHD? Like any muscle, the heart needs a constant supply of oxygen and nutrients that are carried to it by the blood in the coronary arteries. When the coronary arteries become narrowed or clogged and cannot supply enough blood to the heart, the result is CHD. If not enough oxygen-carrying blood reaches the heart, the heart may respond with a pain called angina. The pain is usually felt in the chest or sometimes in the left arm and shoulder. (However, the same inadequate blood supply may cause no symptoms, a condition called silent angina.)WHen the blood supply is cut of completely, the result is a heart attack. The part of the heart that does not receive oxygen begines to die, and some of the heart muscle may be permanently damaged. What causes CHD? CHD is caused by a thickening of the inside walls of the coronary arteries. This thickening, called atherosclerosis, narrows the space through which blood can flow, decreasing and sometimes completely cutting off the supply of oxygen and nutrients to the heart.Atherosclerosis usually occurs when a person has high levels of cholesterol, a fat-like substance, in the blood. Cholesterol and fat, circulating in the blood, build up on the walls of the arteries. This buildup narrows the arteries and can slow or block the flow of blood. When the level of cholesterol in the blood is high, there is a greater chance that it will be depositied onto the artery walls. This process begins in most people during childhood and the teenage years, and worsens as they get older. In addition to high blood cholesterol, high blood pressure and smoking also contribute to CHD. On the average, each of these doubles your chance of developing heart disease. Therefore, a person who has all three risk factors is eight time more likely to develop heart disease than someone who has none. Obesity and physical inactivity are other factors that can lead to CHD. Overweight increases the likelihood of developing high blood cholesterol and high blood pressure, and physical inactivity increases the risk of heart attack. Regular exercise, good nutrition, and smoking cessation are key to controlling the risk factors for CHD.
Research on coronary heart disease (CHD) has contributed to the decline in cardiovascular disease morbidity and mortality that has occurred during the past three decades in the United States. However, life expectancy and rates of illness and death from CHD have not improved as much for blacks as for whites. Blacks have not experienced the full benefit of research advancements for a variety of reasons, including insufficient scientific data, lack of research focused on minority populations, and limited access to health care resources and technology. Consistent and universally accepted racial and ethnic categories have not been established, and definitions may vary according to the social and scientific context. The limited data base currently available leaves a number of paradoxes unresolved. Controversy remains, in particular, regarding both chest pain and sudden death. Available data indicate that the probability of dying from CHD is greater in black Americans than in white Americans and that there is a higher prevalence of smoking, hypertension, diabetes, obesity, and left ventricular hypertrophy (LVH) in blacks. Blacks are also less likely to receive coronary angiography or coronary revascularization. Although major advances in therapy for CHD have occurred in recent years, few data are available on the clinical value, effectiveness, and efficacy of newer therapeutic modalities in blacks. Innovative therapeutic approaches to CHD have been based on data obtained primarily in white male populations. Blacks, especially women, are at greater CHD risk. Therapeutic algorithms focused primarily on the relief of chest pain have been refined in majority populations, but other algorithms may be more efficacious in populations with higher prevalence of hypertension, diabetes, and differing clinical presentations. Although information regarding the interactions of LVH, hypertension, and CHD has increased, there are few data in blacks. |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Read the terms under which this service is provided to you, and our privacy. guidelines.
© Copyright 1999-2000 BHC.com, LLC. All Rights Reserved.
