Introduction
The heart is one of the most important muscles in the human body. It is part of the cardiovascular system, which is made up of both the heart and blood vessels. The key role of the heart is to circulate blood through the body in order to supply oxygen and nutrients to tissues in the body.
The heart is made up of four chambers, blood vessels, four valves, and an electrical system. The four chambers are made up of two atria and two ventricles. They receive deoxygenated blood and pump out oxygen-rich blood into the body. The atria is responsible for receiving the blood that comes back to the heart and the ventricles are responsible for pumping that blood out of the heart. Blood vessels include arteries and veins that are responsible for carrying the blood being pumped out to the rest of the body. The role arteries play is transporting blood to tissues in the body from the heart. The role veins play is carrying the blood back to the heart. The valves in the heart are responsible for preventing the backward flow of blood. The electrical system acts as a natural pacemaker and triggers flexing of the heart.
The coronary arteries are responsible for providing the heart with its own blood supply. There are two major arteries, along with their branches, that are responsible for supplying all parts of the heart with blood. These coronary arteries are the left main coronary artery and the right coronary artery. The left main coronary artery has two branches: the circumflex artery and the left anterior descending artery. Blood in the left atrium, the side of the left ventricle, and the back of the left ventricle are all supplied by the circumflex artery. Blood in the front of the left ventricle, the bottom of the left ventricle, and the front of the septum are all supplied by the left anterior descending artery. The right coronary artery also has two branches: the right marginal artery and the posterior descending artery. Blood in the right atrium, the right ventricle, the bottom part of both ventricles, and the back of the septum are all supplied by the right coronary artery. The right side of the heart is responsible for pumping blood to the lungs and the blood in the right side of the heart is provided by the main part of the right coronary artery. Blood in the bottom part of the left ventricle and the back of the septum are both supplied by the remaining parts of the right coronary artery and the posterior descending artery, which is the main branch, as well as the branches of the circumflex artery.
Pathophysiology
Coronary artery is the leading cause of death in men and women in the United States. It occurs when there is a buildup of cholesterol and plaque on the inner walls of the arteries that are responsible for supplying blood to the heart. This causes the arteries to become hardened and narrowed. The buildup of cholesterol and plaque is called atherosclerosis. The arteries blood flow is lessened as this buildup grows. For this reason, the heart is unable to get the oxygen and blood that is needed which can lead a person to have angina (or chest pain) or even a heart attack. If not treated soon enough, coronary artery disease can make the heart weak and cause heart failure. This means that the heart is unable to thoroughly pump blood to the body.
Susceptible groups to coronary artery disease include men and women between ages 40 and 60 years old. It occurs in approximately 5-9% of 20 year olds or people around 20 years old. The mortality rate is higher for men compared to women, except after the age of 55 in which the rate grows for women.
Diagnostic Tools
There are several methods to diagnose coronary artery disease. One is the intravascular ultrasonography (IVUS). It is a powerful tool that is used to evaluate and distinguish coronary vessels as well as plaque caused by atherosclerosis. It works by creating pictures with an ultrasound transducer set on a catheter. This catheter is then put inside the coronary artery until it arrives at the position needed to study the particular segment. A series of pictures are taken of the coronary artery as the catheter is slowly being removed. Each of these pictures shows a 360 degree, cross-sectional look at the different layers of the coronary artery. The IVUS can also be used to place stents in the coronary vessels.
Another method used to diagnose coronary artery disease is multiple-splice spiral computed tomography (MSCT), which is basically a cardiac CT scan. Because the heart is always moving, it can be very difficult to get pictures of coronary vessels. With new and updated CT scanners which include higher speed and better photo resolution, it's become much easier to analyze the anatomy of the heart. But, one downside is that the “thinner†slices are vulnerable to noise, so the scans of those with a body mass index greater than 40 are usually non-diagnostic. The MSCT takes a very short amount of time, approximately 10-15 seconds. Even with this newer CT scan, obtaining a good image of the heart is still difficult because of all the movement. The best pictures are obtained when one’s heart rate is less than 65 beats per minute, in addition to a regular cardiac rhythm.
A cardiovascular MRI is yet another way to diagnose coronary artery disease. Specifically, it is called a coronary magnetic resonance angiography (MRA). The MRA depicts important coronary arteries and it doesn’t use any contrast injections or expose patients to radiation. The MRA works by taking an image during the short time in which the heart is still during the cardiac cycle. All of the images are combined to create the final product. This process can take up to 10 minutes. Currently, the MSCT is used more than the MRA to detect coronary artery disease.
Risk Factors
Common risk factors in the development of coronary artery disease include family history, diabetes mellitus, and the use of cigarettes. Others include alcoholism, and hypertension.
If one has a family history of coronary artery disease, it is seen as a risk factor. This is especially true if the family member who had it was an immediate family member. If the family member was diagnosed with coronary artery disease at an early age, then the person has a greater chance for getting coronary artery disease compared to the rest of the population. It has been found that more than 250 genes are involved in coronary artery disease.
Individuals with diabetes are at higher risk of coronary artery disease than those who don’t suffer from diabetes. Coronary artery disease is the leading cause of death in individuals who suffer from type 2 diabetes.
Smoking cigarettes is another notable risk factor for coronary artery disease, as well as other cardiovascular diseases. The risk of developing coronary artery disease is increased by how many cigarettes the patient smokes each day. This is mainly due to the fact that tobacco smoke is a risk factor for cardiovascular diseases because it can create insulin resistance. Although smoking increases the risk of developing all cardiovascular diseases, how much the risk is increased depends on the type of cardiovascular disease since it’s different for all of them.
Patients that experience hypertension are at an increased risk of developing cardiovascular issues. Cardiovascular risk can actually be decreased by treating hypertension. The consumption of alcohol is also associated with hypertension. The higher intake of alcohol present, the higher the risk of having a stroke or myocardial infarction.
Treatment Methods
There are multiple methods of treatment for coronary artery disease. They range from everyday lifestyle changes to surgeries. It all really depends on the severity of it when it is diagnosed.
Multiple lifestyle changes can be made in order to treat coronary artery disease. Following a healthy diet is one method that can help treat this disease. Healthy foods can aid in preventing and reducing high blood pressure and cholesterol. It also helps the patient stay at a healthy weight which can also be advantageous. Exercising regularly is another lifestyle change that can be made to treat coronary artery disease by offering the same benefits as eating healthy. For patients who smoke cigarettes regularly, simply quitting can treat this disease as well. The final lifestyle change, among many, that can be made is managing stress. Stress can trigger heart attacks and can also cause patients to turn to unhealthy habits such as smoking and drinking.
Some doctors may prescribe certain medicines to patients with coronary artery disease which can help lower cholesterol and blood pressure. This will slow plaque buildup in the patient. When coronary artery disease is diagnosed late, making it very severe, surgery may be needed to treat it. An angioplasty is a procedure in which the surgeon opens the blocked or narrowed arteries. A coronary artery bypass grafting is a surgery in which arteries or veins from other parts of the patient’s body are used to bypass the narrowed arteries. A carotid artery surgery is performed to remove the buildup of plaque in the neck.
Prognosis
The prognosis for patients who suffer from coronary artery disease differs depending on the severity of the disease and whether or not treatment worked. Everyone is different, therefore some maintain their health through lifestyle changes such as eating better or quitting smoking. Others use medications, and in worst case scenarios, some need surgery. All in all, if coronary artery disease is diagnosed early, the outcome is much better for the patient.
Conclusion
In conclusion, I learned that patients can live a healthy life while suffering from coronary artery disease. The outcome isn’t always bad, and there are various ways in which one can treat the disease. Due to new technology, it is much easier to catch coronary artery disease and diagnose it earlier rather than later when it’s more severe. It helps to know the risk factors and the symptoms of coronary artery disease in order to diagnose it early on.