Coronary Artery Disease

 

 

When you think of heart disease, usually people think of coronary artery disease (narrowing of the arteries leading to the heart), but coronary artery disease is just one type of cardiovascular disease. Coronary artery disease (CAD) is atherosclerosis, or hardening, of the arteries that provide vital oxygen and nutrients to the heart.

 

What is Coronary Artery Disease?

Coronary artery disease is atherosclerosis of the coronary arteries. Atherosclerosis occurs when the arteries become clogged and narrowed, restricting blood flow to the heart. Without adequate blood, the heart becomes starved of oxygen and vital nutrients it needs to work properly.

 

How does Coronary Artery Disease Develop?

Your coronary arteries are hollow tubes. Inside, they are smooth and elastic, allowing blood to flow freely. Before your teen years, fat starts to deposit in the blood vessel walls. As you get older, the fat builds up. This causes injury to your blood vessel walls. In an attempt to heal itself, the cells release chemicals that make the walls sticky.

 

Then, other substances such as inflammatory cells, proteins and calcium that travel in your bloodstream start sticking to the vessel walls. The fat and other substances combine to form a material called plaque. The plaque builds up and narrows the artery (atherosclerosis).

 

Many of the plaque deposits are hard on the outside and soft and mushy on the inside. The hard surface can crack or tear, exposing the soft, fatty inside. When this happens, platelets (disc-shaped particles in the blood that aid clotting) come to the area, and blood clots form around the plaque. This causes the artery to narrow even more.

 

Over time, the inside of the arteries develop plaques of different sizes. Many of the plaque deposits are hard on the outside and soft and mushy on the inside. The hard surface can crack or tear, exposing the soft, fatty inside. When this happens, platelets (disc-shaped particles in the blood that aid clotting) come to the area, and blood clots form around the plaque. This causes the artery to narrow even more. Sometimes, the blood clot breaks apart by itself, and blood supply is restored.

 

Over time a narrowed coronary artery may develop new blood vessels that go around the blockage to get blood to the heart. However, during times of increased exertion or stress, the new arteries may not be able to supply enough oxygen-rich blood to the heart muscle.

 

In other cases, the blood clot may totally block the blood supply to the heart muscle, causing what is called an acute coronary syndrome.

 

There is actually a name given to three serious conditions:

 

  • Unstable angina: can often be relieved with oral medications, is unstable and may progress to a heart attack. Usually more intense medical treatment or a procedure is required to treat this acute coronary syndrome.

  • Non-ST segment elevation myocardial infarction (NSTEMI) or "non-Q-wave MI": This heart attack, or MI, does not cause typical changes on an electrocardiogram (ECG). However, chemical markers in the blood indicate that damage has occurred to the heart muscle. (Referred to as cardiac enzymes)

  • ST segment elevation myocardial infarction (STEMI) or "Q-wave MI": This heart attack, or MI, is caused by a prolonged period of blocked blood supply. It affects a large area of the heart muscle, and causes changes on the ECG as well as chemical markers in the blood.

 

What is Ischemia?

 

When plaque and fatty matter narrow the inside of an artery to a point where it cannot supply enough oxygen-rich blood to meet your organ's needs, cramping of the muscle occurs. This is called ischemia. Ischemia of the heart can be compared to a cramp in the leg. When someone exercises for a very long time, the muscles in the legs cramp up because they're starved for oxygen and nutrients. Your heart, also a muscle, needs oxygen and nutrients to keep working. If its blood supply is inadequate to meet the heart muscle's needs, ischemia occurs, and you may feel chest pain or other symptoms.

 

Ischemia is most likely to occur when the heart demands extra oxygen. This is most common during:

 

 

  • Exertion (activity)

  • Eating

  • Excitement or stress

  • Exposure to cold

 

Coronary artery disease can progress to a point where ischemia occurs even at rest. When ischemia is relieved in a short period of time (less than 10 minutes) with rest or medications, you may be told you have "stable coronary artery disease" or "stable angina".

 

What are the Symptoms of Coronary Artery Disease?

 

The most common symptom is angina or "angina pectoris." Angina can be described as a discomfort, heaviness, pressure, aching, burning, numbness, fullness, squeezing or painful feeling. It can be mistaken for indigestion or heartburn. Angina is usually felt in the chest, but may also be felt in the left shoulder, arms, neck, back or jaw.

 

Other symptoms that can occur with coronary artery disease include:

 

 

  • Shortness of breath

  • Excessive tiredness

  • Palpitations (irregular heart beats, skipped beats or a "flip-flop" feeling in your chest)

  • A faster heartbeat

  • Weakness or dizziness

  • Nausea

  • Sweating

 

Learn to recognize your symptoms and the situations that cause them. Call your doctor if you begin to have new symptoms or if they become more frequent or severe. If you or someone you are with experience chest discomfort, especially with one or more of the symptoms listed above, don't wait longer than a few minutes (no more than 5) before calling 082 911 or any other medical emergency number, to get help.

 

If you have angina and have been prescribed nitroglycerin, call your doctor or have someone take you to the nearest emergency room if pain persists after taking three doses (taken at five-minute intervals) or after 15 minutes.

 

Emergency personnel may tell you to chew an aspirin to break up a possible blood clot, if there is not a medical reason for you to avoid aspirin.

 

Ischemia, and even a heart attack, can occur without any warning symptoms. This is called silent ischemia. It can occur among all people with heart disease, though it is more common among people with diabetes.

 

What Happens During a Heart Attack?

 

The heart muscle requires a constant supply of oxygen-rich blood to nourish it. The coronary arteries provide the heart with this critical blood supply. If you have coronary artery disease, those arteries become narrow and blood cannot flow as well as it should. Fatty matter, calcium, proteins and inflammatory cells build up within the arteries to form plaques of different sizes. The plaque deposits are hard on the outside and soft and mushy on the inside.

 

 

 

 

When the plaque's hard, outer shell cracks (plaque rupture), platelets (disc-shaped particles in the blood that aid clotting) come to the area, and blood clots form around the plaque. If a blood clot totally blocks the artery, the heart muscle becomes "starved" for oxygen. Within a short time, death of heart muscle cells occurs, causing permanent damage. This is called a myocardial infarction (MI), or heart attack.

 

While it is unusual, a heart attack can also be caused by a spasm of a coronary artery. During coronary spasm, the coronary arteries restrict or spasm on and off, reducing blood supply to the heart muscle (ischemia). It may occur at rest and can even occur in people without significant coronary artery disease.

 

Each coronary artery supplies blood to a region of heart muscle. The amount of damage to the heart muscle depends on the size of the area supplied by the blocked artery and the time between injury and treatment.

 

Healing of the heart muscle begins soon after a heart attack and takes about eight weeks. Just like a skin wound, the heart's wound heals and a scar will form in the damaged area. But, the new scar tissue does not contract or pump as well as healthy heart muscle tissue. So, the heart's pumping ability is lessened after a heart attack. The amount of lost pumping ability depends on the size and location of the scar.

 

What are the Symptoms of a Heart Attack?

 

Symptoms of a heart attack include:

 

 

  • Discomfort, pressure, heaviness, or pain in the chest, arm or below the breastbone

  • Discomfort radiating to the back, jaw, throat or arm

  • Fullness, indigestion or choking feeling (may feel like heartburn)

  • Sweating, nausea, vomiting or dizziness

  • Extreme weakness, anxiety or shortness of breath

  • Rapid or irregular heartbeats

 

During a heart attack, symptoms last 30 minutes or longer and are not relieved by rest or oral medications (medications taken by mouth).

 

Some people have a heart attack without having any symptoms (a "silent" myocardial infarction). A silent MI can occur in any person, though it is more common among diabetics.

 

What Do I Do if I Have a Heart Attack?

 

Quick treatment to open the blocked artery is essential to lessen the amount of damage. At the first signs of a heart attack, call for emergency treatment (usually 082 911). The best time to treat a heart attack is within one to two hours of the first onset of symptoms. Waiting longer than that increases the damage to your heart and reduces your chance of survival.

 

Keep in mind that chest discomfort can be described many ways. It can occur in the chest or in the arms, back or jaw. If you have symptoms, take notice. These are your heart disease warning signs. Seek medical care immediately.

 

What Other Treatment Options Are There?

 

During or shortly after a heart attack, you may go to the cardiac catheterization laboratory for direct evaluation of the status of your heart, arteries and the amount of heart damage. In some cases, procedures (such as angioplasty or stents) are used to open up your narrowed or blocked arteries. These procedures may be combined with thrombolytic therapy (drug treatments) to open up the narrowed arteries, as well as to break up any clots that are blocking them. 

 

Angioplasty 

 

If necessary, bypass surgery may be performed to restore the heart muscle's supply of blood.Treatments (medications, open heart surgery and interventional procedures, like angioplasty) do not cure coronary artery disease. Having had a heart attack or treatment does not mean you will never have another heart attack; it can happen again. But, there are several steps you can take to prevent further attacks.

 

What Lifestyle Changes Will I Need to Make?

 

There is no cure for coronary artery disease. In order to prevent the progression of this disease, you must follow your doctor's advice and make necessary lifestyle changes.

 

 

  • You can stop smoking,

  • Lower your blood cholesterol,

  • Control your diabetes

  • Control high blood pressure,

  • Follow an exercise plan,

  • Maintain an ideal body weight,

  • Control stress.

 

Encouraging Safe Exercise in A Heart Disease Patient

 

 

  • What exercises are best? Here are some things to discuss with your doctor:

  • Medication changes. New medications can greatly affect your response to exercise; your loved one's doctor can tell you if his/her normal exercise routine is still safe.

  • Heavy lifting. Make sure that lifting or pushing heavy objects and chores such as raking, shoveling, mowing, or scrubbing aren't off limits. Chores around the house can be tiring for some people; make sure your loved one only does what he/she is able to do without getting tired.

  • Safe exercises. Get the doctor's approval before you let your loved one lift weights, use a weight machine, jog, or swim.

 

General Workout Tips for People with Heart Disease

 

  • Be sure any exercise is paced and balanced with rest.

  • Ask your biokineticist about avoiding isometric exercises such as push-ups and sit-ups. Isometric exercises involve straining muscles against other muscles or an immovable object.

  • Don't exercise outdoors when it is too cold, hot, or humid. High humidity may cause him or her to tire more quickly; extreme temperatures can interfere with circulation, make breathing difficult, and cause chest pain. Better choices are indoor activities such as mall walking or training in a gym.

  • Make sure you stay hydrated. It is important to drink water even before you feel thirsty, especially on hot days.

  • Extremely hot and cold showers or sauna baths should be avoided after exercise. These extreme temperatures increase the workload on the heart.

  • Steer clear of exercise in hilly areas. If he/she must walk in steep areas, make sure they slow down when going uphill to avoid working too hard. Use a heart rate monitor to be aware of the patient’s heart rate.

  • If your exercise program has been interrupted for a few days (for example, due to illness, vacation, or bad weather), make sure they ease back into the routine. Start with a reduced level of activity, and gradually increase it until you are back where you started.

 

Exercise Precautions

 

There are many precautions a caregiver must keep in mind when developing an exercise program for one with heart disease. Keep the following tips in mind.

 

 

  • Stop the exercise if you becomes overly fatigued or short of breath; discuss the symptoms with your doctor or schedule an appointment for evaluation.

  • Do not encourage exercise if you are not feeling well or has a fever. Heart patients should wait a few days after all symptoms disappear before restarting the exercise program, unless their doctor gives other directions.

  • Stop the activity if you develops a rapid or an irregular heartbeat or if you have heart palpitations. Check your pulse after you have rested for 15 minutes. If it's still above 100-120 beats per minute, call the doctor for further instructions.

 

If you experience pain:

 

Don't ignore it. If he or she has chest pain or pain anywhere else in the body, do not allow the activity to continue. Performing an activity while in pain may cause stress or damage to the joints.

 

Stop the exercise and rest if you:

 

 

  • Feel weak.

  • Are dizzy or lightheaded.

  • Have unexplained weight gain or swelling (call the doctor right away).

  • Have pressure or pain in the chest, neck, arm, jaw, or shoulder.

  • Have any other symptoms that cause concern.