Diseases of the Cardiovascular System The Cardiovascular System

Diseases of the Cardiovascular System

The Cardiovascular System has three components: 1. The blood 2. The blood vessels 3. The heart Disorders can affect any of these parts.

1. Disorders of the Blood a) Anemia • a lower than normal number of RBCs or amount of hemoglobin in the blood • may be due to excessive blood loss (including from menstruation), iron deficiency, vitamin B 12 deficiency or many other reasons • the blood can not carry as much oxygen so the person is pale, tires easily and may have trouble concentrating

1. Disorders of the Blood b) Leukemia • a group of cancers which produce higher than normal number of WBCs in the blood • may be acute (rapid onset) or chronic (progress over a long period of time) • symptoms include fatigue, abnormal bruising, swollen lymph glands • can be treated with chemotherapy and radiation

2. Disorders of the Blood Vessels a) Atherosclerosis • hardening of the arteries due to a build up of plaque inside blood vessel walls • plaque is made of cholesterol, fat and calcium • plaque causes arteries to lose their elasticity, increasing blood pressure • plaque reduces the diameter of the artery, decreasing blood flow • plaques may rupture, causing a blood clot to form which further reduces blood flow

2. Disorders of the Blood Vessels a) Atherosclerosis (cont. ) • atherosclerosis in the coronary arteries that supply blood to the heart may cause angina (heart pain) due to reduced oxygen to the heart muscle cells or a heart attack if the blood supply is completely cut off

A Blocked Coronary Artery causes a Heart Attack (Myocardial Infarction)

2. Disorders of the Blood Vessels a) Atherosclerosis (continued) Angioplasty - A catheter is inserted into the blocked artery. A balloon in the catheter is inflated to compress the plaque, opening the artery. A metal stent is left behind to hold the blood vessel open, maintaining blood flow.

2. Disorders of the Blood Vessels a) Atherosclerosis (continued) • if a coronary artery is too badly blocked to be opened with angioplasty, coronary bypass surgery may be required in which a healthy blood vessel is stitched into place to “bypass” (get around) the clogged artery A single bypass (one coronary artery was blocked) A triple bypass (three coronary arteries were blocked)

2. Disorders of the Blood Vessels a) Atherosclerosis (cont. ) • atherosclerosis in an artery that supplies blood to the brain may cause an ischemic stroke • the brain tissue past the blockage dies due to lack of blood and oxygen

2. Disorders of the Blood Vessels a) Atherosclerosis (cont. ) • know the signs of a stroke • if you suspect that a person is having a stroke, respond immediately • giving a person t. PA (from snake venom) within a few hours of a stroke can dissolve any clots and restore blood flow to the brain, preventing permanent brain damage (”clot busting drugs”)

Symptoms of Stroke: Face Creases are different on each side of the face

Symptoms of Stroke: Face

Symptoms of Stroke: Face

Symptoms of Stroke: Arms

Symptoms of Stroke: Arms

2. Disorders of the Blood Vessels a) Atherosclerosis (continued) • may be prevented by staying active, maintaining a normal body weight and eating a healthy diet • many people take “blood thinners” such as aspirin (or cinnamon…be careful!!) which prevent platelets from sticking to one another and forming clots

2. Disorders of the Blood Vessels b) Aneurysms • a ‘weak spot’ which creates a bulge in the wall of an artery • as blood continues to flow through the artery, the bulge may burst, causing serious internal bleeding • occurs most commonly where arteries branch (bifurcate) • can occur anywhere in the body • can be corrected with surgery

2. Disorders of the Blood Vessels c) Varicose veins • enlarged, twisted veins due to valves weakening and allowing blood to flow backward • blood pools in the vein below the weakened valve, stretching and distorting the vein

3. Disorders of the Heart a) Heart Valve problems • A valve in the heart does not open or close properly • if a valve does not close properly, blood flows backward through the valve • valve problems decrease the efficiency of blood flow so the person feels light-headed, tired and may pass out during exertion • can be treated with drugs replacement valves

3. Disorders of the Heart b) Arrhythmias (‘without rhythm’) • a condition in which the electrical activity and pumping of the resting heart is abnormal (too slow, too fast, or irregular) • blood is not pumped effectively, so the person feels light-headed, tired and may pass out • if the arrhythmia is caused by a problem with the SA node in the right atrium, treatment may involve implanting a pacemaker under the skin of the chest to regulate the heart rate

3. Disorders of the Heart b) Arrhythmias (continued) • if the arrhythmia causes the ventricles to beat too quickly (ventricular tachycardia or ventricular fibrillation), the person may be treated with a defibrillator (eg. AED, automatic external defibrillator) • the defibrillator sends an electric current through the heart which stops the heart from beating • it is hoped that once the SA node resumes firing, the heart will come back into rhythm

3. Disorders of the Heart b) Arrhythmias (continued)