CoronaryArtery

Disease

CoronaryArtery

Disease

What is coronary artery

disease?

A narrowing of the coronary arteries that prevents adequate blood supply to the heart muscle. Usually caused by atherosclerosis, it may progress to the point where the heart muscle is damaged due to lack of blood supply. Such damage may result in infarction, arrhythmias, and heart failure.

•Is a muscle about the size of your fist•Weighs approximately one pound•Is located behind and slightly to the left of the breastbone•Pumps about 5 quarts (4.7 liters) of blood every minute

The function of the heart is to circulate blood throughout the body by:

•Pumping blood through the lungs removes carbon dioxide and refreshes the blood with oxygen

•The oxygenated blood is pumped to the body to provide oxygen and nutrients and to remove waste products.

•The coronary arteries are the blood vessels that supply blood and oxygen to the heart muscle.

                                                                                                                   

2 coronary arteries branch from the main aorta just above the aortic valve. “No larger than drinking straws, they divide and encircle the heart to cover its surface with a lacy network . They carry out about 130 gallons of blood through the heart muscle daily.” (Clark, 119)

Blood Supply To The Heart

Coronary Artery Disease• Coronary artery disease is one of the most common

and serious effects of aging. Fatty deposits build up in blood vessel walls and narrow the passageway for the movement of blood. The resulting condition, called atherosclerosis often leads to eventual blockage of the coronary arteries and a “heart attack”.

Deposition of fatty substances in the inner layer of an artery forming a plaque

The Plaque– How is it formed ?

• Damage to the endothelial cells

• Fats,cholesterol,monocytes,platelets….. Deposited in arterial walls

Complications of Atherosclerosis

• Narrowing of arterial lumen

• Plaque fissure

• Thrombus formation

Coronary artery disease

• When atherosclerosis affects the coronary arteries it results in Coronary artery disease

Pathophysiology

• coronary artery disease occurs when part of the smooth, elastic lining inside a coronary artery (the arteries that supply blood to the heart muscle) develops atherosclerosis.

• With atherosclerosis, the artery's lining becomes hardened, stiffened, and swollen with all sorts of "grunge" - including calcium deposits, fatty deposits, and abnormal inflammatory cells - to form a plaque. Deposits of calcium phosphates (hydroxyapatites) in the muscular layer of the blood vessels appear to play not only a significant role in stiffening arteries but also for the induction of an early phase of coronary arteriosclerosis.

• High blood cholesterol• High blood pressure• Smoking• Obesity• Lack of physical activity

Risk Factors

UncontrollableUncontrollable

•Sex

•Hereditary

•Race

•Age

ControllableControllable

•High blood pressure

•High blood cholesterol

•Smoking

•Physical activity

•Obesity

•Diabetes

•Stress and anger

Signs and Symptoms• None: This is referred to as silent

ischemia. Blood to your heart may be restricted due to CAD, but you don’t feel any effects.

• Chest pain: If your coronary arteries can’t supply enough blood to meet the oxygen demands of your heart, the result may be chest pain called angina.

• Shortness of breath: Some people may not be aware they have CAD until they develop symptoms of congestive heart failure- extreme fatigue with exertion, shortness of breath and swelling in their feet and ankles.

• Heart attack: Results when an artery to your heart muscle becomes completely blocked and the party of your heart muscles fed by that artery dies.

Signs & Symptoms

NoneChestPain

ShortnessOf Breath

HeartAttack

• Many people are able to manage coronary artery disease with lifestyle changes and medications.

• Other people with severe coronary artery disease may need angioplasty or surgery.

Nitroglycerine SL

– Carry NTG on person at all time– Sit or lie down when taking– Take one tablet under tongue every 5 min

until angina relieved. If no relief after 3 tabs, call emergency

– May take immediately before activity causing angina

Beta blockers

– Reduce myocardial oxygen consumption by decreasing heart rate, contractility and blood pressure

– Caution client not to stop med abruptly; may cause rebound angina

– Monitor heart failure clients for worsening failure

– Side effects – hypotension, bradycardia, bronchial spasm, masks hypoglycemia

– Ex: Lopressor or Toprol (metoprolol), Inderal (propranolol), Tenormin (Atenolol)

Calcium channel blockers

– Dilate arteries – decreases SVR which decreases workload and O2 consumption

– Decrease heart rate and myocardial contractility – decreases O2 consumption

– Avoid in clients with severe heart failure– Side effects - hypotension, bradycardia, constipation,

edema, AV blocks– Ex: Adalat or Procardia (nifedipine), Cardene

(nicardipine), Cardizem (diltiazem)

Antiplatelet medications

– Prevent platelet aggregation on atheroma or thrombus

• ASA – side effects: GI irritation, bleeding, increased bruising

• Ticlid (ticlopidine) – side effects: neutropenia, GI upset, N/V/D, rash. Must monitor CBC

• Plavix (clopidogrel) – side effects: increased bleeding tendencies, N/V/D, rash

Antcoagulants

Heparin• Given IV in acute situations or subcutaneous in

non-acute situations• Monitor partial thromboplastin time (PTT) • Antidote – Protamine Sulfate• Observe bleeding precautions• Monitor for signs and symptoms of bleeding• Half-life of 1-2 hrs• Monitor for Heparin induced thrombocytopenia

(HIT)

Other Drugs

– Cholesterol lowering medications, such as statins, are useful to decrease the amount of "bad" (LDL) cholesterol.

– ACE inhibitors, which treat hypertension and may lower the risk of recurrent myocardial infarction

– Aspirin

Oxygen therapy

– Administered usually at 2 L/min per nasal cannula

– Increases amount of O2 delivered to myocardium

                                                                                                                                                

Treatment (continued)

1) Stenting

• a stent is introduced into a blood vessel on a balloon catheter and advanced into the blocked area of the artery

• the balloon is then inflated and causes the stent to expand until it fits the inner wall of the vessel, conforming to contours as needed

• the balloon is then deflated and drawn back

•The stent stays in place permanently, holding the vessel open and improving the flow of blood.

Treatment (continued)

2) Angioplasty• a balloon catheter is passed through the guiding catheter to the area near the narrowing. A guide wire inside the balloon catheter is then advanced through the artery until the tip is beyond the narrowing.

• the angioplasty catheter is moved over the guide wire until the balloon is within the narrowed segment.

• balloon is inflated, compressing the plaque against the artery wall

• once plaque has been compressed and the artery has been sufficiently opened, the balloon catheter will be deflated and removed.

Treatment (continued)

3) Bypass surgery

• healthy blood vessel is removed from leg, arm or chest

• blood vessel is used to create new blood flow path in your heart

• the “bypass graft” enables blood to reach your heart by flowing

around (bypassing) the blocked portion of the diseased artery. The increased blood flow reduces angina and the risk of heart attack.

•Get regular medical checkups.

•Control your blood pressure.

•Check your cholesterol.

•Don’t smoke.

•Exercise regularly.

•Maintain a healthy weight.

•Eat a heart-healthy diet.

•Manage stress.