CARDIOVASCULAR DISEASE

How to Reduce Of CARDIOVASCULAR DISEASE

PREVALENCE OF CARDIOVASCULAR DISEASE 

Cardiovascular diseases are directly related to over 40% of deaths in the United States and indirectly related to a large percentage of additional deaths.

Heart disease, stroke, and related blood vessel disorders combined to kill nearly 1 million Americans in 1994 (Figure 10-1). This figure represents more deaths than were caused by cancer, accidents, pneumonia, influenza, lung diseases, diabetes, and AIDS combined. Indeed, cardiovascular disease is our nation's number one "killer" 

NORMAL  CARDIOVASCULAR FUNCTION 

The cardiovascular or circulatory system uses a muscular pump to send a complex fluid on a continuous trip through a closed system of tubes. The pump is the heart, the fluid is blood, and the closed system of tubes is the network of blood vessels. 

The Vascular System

 The term vascular system refers to the body's blood vessels. Although we might be familiar with the arteries (vessels that carry blood away from the heart) and the veins (vessels that carry blood toward the heart), arterioles, capillaries, and venues are also included in the vascular system. Arterioles are the farther, smaller-diameter extensions of arteries. These arterioles lead eventually to capillaries, the smallest extensions of the vascular system. 

At the capillary level, exchanges of oxygen, food, and waste occur between cells and the blood. Once the blood leaves the capillaries and begins its return to the heart, it drains into small veins, or venules. The blood in the venules flows into increasingly larger vessels called veins. Blood pressure is highest in arteries and lowest in veins, especially the largest veins, which empty into the right atrium of the heart. 

The Heart 

The heart is a four-chambered pump designed to create the pressure required to circulate blood throughout the body. Usually considered to be about the size of a person's clenched fist, this organ lies slightly tilted between the lungs in the central portion of the thorax. The heart does not lie completely in the center of the chest. Rather, approximately two thirds of the heart is to the left of the body mid-line and one third is to the right. Two upper chambers, called atria, and two lower chambers, called ventricles, form the heart. The thin-walled atrial chambers are considered collecting chambers, whereas the thick-walled muscular ventricles are considered the pumping chambers.

 The right and left sides of the heart are divided by a partition called the septum. Study and follow the flow of blood through the heart's four chambers. For the heart muscle to function well, it must be supplied with adequate amounts of oxygen. The two main coronary arteries (and their numerous branches) accomplish this. These arteries are located outside of the heart  If the coronary arteries are diseased and not functioning well, a heart attack is possible. 

CARDIOVASCULAR DISEASE RISK FACTORS 

what are the factors of Cardiovascular Disease

As you have just read, the heart and blood vessels are among the most important structures in the human body. By protecting your cardiovascular system, you lay the groundwork for a more exciting, productive, and energetic life. The best time to start protecting and improving your cardiovascular system is early in life, when lifestyle patterns are developed and reinforced (see the Star Box at right). Of course, it is difficult to move backward through time, so the second best time to start protecting your heart is today. Improvements in certain lifestyle activities can pay significant dividends as your life unfolds. Complete the Personal Assessment on pp. 232-233 to determine your risk for heart disease. The American Heart Association encourages people to protect and enhance their heart health by examining the 10 cardiovascular risk factors that are related to various forms of heart disease' A cardiovascular risk factor is an attribute that a person has or is exposed to that increases the likelihood that he or she will develop some form of heart disease. Three risk factors are ones you will be unable to change. An additional four risk factors are ones you can clearly change. Three final risk factors are ones that are thought to be contributing factors to heart disease. 

Risk Factors That Cannot Be Changed 

The three risk factors that you cannot change are increasing age, male gender, and heredity.Despite the fact that these risk factors cannot be changed, your knowledge that they might be an influence in your life should encourage you to make a more serious commitment to the risk factors you can change. 

Increasing age 

Heart diseases tend to develop gradually over the course of one's life. Although we may know of a per-son or two who experienced a heart attack in their thirties or forties, most of the serious consequences of heart disease are evident in older ages. For example, approximately 80% of people who die from heart attack are age 65 and older. 

Male gender 

Young women have lower rates of heart disease than young men. Yet when women move through menopause (typically in their fifties), their rates of heart disease are similar to men's rates. It is thought that women are some-what more protected from heart disease than men because of their natural production of the hormone estrogen during their fertile years.

Heredity Like

 increasing age and male gender, this risk factor cannot be changed. By the luck of the draw, some people are born into families where heart disease has never been a serious problem, whereas others are born into families where heart disease is quite prevalent. In this latter case, children are said to have a genetic predisposition (tendency) to develop heart disease as they grow and develop throughout their lives. These people have every reason to be highly motivated to reduce the risk factors they can control. Race is also a consideration related to heart disease. African-Americans have moderately high blood pres-sure at rates twice that of whites and severe hypertension at rates three times higher than whites (for a detailed discussion of this topic, see "Focus on Hypertension among African-Americans). Hypertension significantly increases the risk of both heart disease and stroke. Fortunately, as you will soon read, hypertension can be controlled through a variety of methods.