Module 5 Patho Cardiovascular System

14 Steps in the Cardiac Cycle

1. Deoxygenated blood starts to run from the body

2. It flows into Superior/Inferior Vena Cava

3. The flow of deoxygenated blood reaches the right atrium

4. The atrium will push through the Tricuspid valve

5. into the right ventricle

6. Will continue to pass the systemic veins and flow into the pulmonary valve

7. The oxygenated blood is pumped into the lungs through the systemic arteries. The marginal arteries will provide the heart muscle with blood.

8. The oxygenated blood comes into the pulmonary veins

9. Into the left atrium

10. The flow of blood goes through the bicuspid valve

11. Into the left ventricle

12. Moves to the aortic valve

13. Flowing through the aorta and coronary arteries

14. The oxygen-rich blood moves back to papillary muscle and the body

SA node

The natural pacemaker of the heart

Coronary Arteries

• Coronary circulation is done by coronary arteries

• Blood within the heart chambers do not supple oxygen and other nutrients to the cells of the heart

• Heart structures are nourished by vessels of the systemic circulation

Calcium

Is needed for all electrical activity in the heart

Preload

• Volume of blood in ventricles at end of diastole (end diastolic pressure)

• Increased in: hypervolemia, regurgitation of cardiac valves, heart failure

Afterload

• Resistance left ventricle must overcome to circulate blood

• Increased in: hypertension, vasoconstriction

• Increased afterload = Increased cardiac workload

Thrombus

A blood clot that remains attached to a vessel wall (thromboembolism is a detached clot)

Emboli

• The obstruction of a vessel by an embolus, a bolus of matter circulating in the bloodstream.

• Can be caused by: air, aggregate of amniotic fluid, fat, bacteria, cancer cells, foreign substance

Pulmonary Emboli

Originate on the venous side usually from the deep veins of the legs

Systemic Emboli

Most commonly originate in the left heart

Symptoms of Thrombus and Emboli

• Peripheral is warm, red, edema, pain

• Pulmonary is SOB, decreased pulse oximetry

• In organs, pain

depends on location

PAD (peripheral artery disease)

• Atherosclerotic disease of the arteries that perfuse the limbs

• Symptoms: intermittent claudication (muscle cramps w/ pain), severe pain, loss of pulses, skin color changes

Risk Factors for Hypertension

• Advancing age

• Obesity

• Gender (men<50, women>50)

• High dietary sodium intake

• Glucose intolerance

• Family history

• Smoking

• ETOH abuse

• Black race

• Low dietary intake of potassium, calcium or magnesium

Orthostatic Hypotension

Refers to a decrease in both systolic and diastolic arterial blood pressure

• Upon standing it drops > 20 mm

• HR goes up > 10 beats per minute

Aneurysm

• Localized dilation or outpouching of a vessel wall or cardiac chamber, produced by stretching

• The thoracic or abdominal aorta is particularly susceptible

• Atherosclerosis is the most common cause of aneurysms

• Usually asymptomatic until rupture

Thromboangiitis (Buerger)

• An inflammatory disease of the peripheral arteries accompanied by thrombi, inflammation and vasospasm of arterial segments

• Occurs mostly in young men and heavy cigarette smokers

Raynaud Phenomenon

• Attacks of vasospasm in the small arteries and arterioles of fingers

• Tends to affect young women

• Attacks are triggered by brief exposure to cold or emotional stress

Arteriosclerosis

• A chronic disease with abnormal thickening and hardening of the vessel walls, causing gradual narrowing of the arterial lumen

• Pathophysiologic conditions include: 1. high BP, 2. insufficient perfusion of tissues, 3. weakening and outpouching of arterial walls

Atherosclerosis

• Begins with injury to the endothelial cells that line artery walls- accumulation of lipid laden macrophages

• Most common cause of CAD (coronary artery disease)

Coronary Artery Disease

• Any vascular disorder that narrows or occludes the coronary arteries

• Causes more than 500,000 myocardial infarctions (MI) per year

• Causes one third of all deaths in the United States

Non-modifiable Risk Factors of CAD

• Age

• Male gender

• Family

• Stress

• Race

Modifiable Risk Factors of CAD

• Smoking, ETOH, obesity, sedentary lifestyle

• DM, hypercholesterolemia (>240 mg/dL)

• Hyperlipidemia (LDL>160mg/dL)

• HTN

• Elevated triglycerides

Acute Coronary Syndrome

1. Stable angina

2. Unstable angina

3. NSTEMI

4. STEMI

Stable Angina

• There is an increased demand of the stable atherosclerotic plaque

• Normal ECG and Troponins

Unstable Angina

• Plaque ruptures and a thrombus forms, causing partial occlusion of the vessel

• ECG- can be normal, have T waves or ST depression

• Normal troponins

NSTEMI

• The plaque rupture and thrombus formation causes partial occlusion to the vessel that results in injury and infarct to the subendocardial myocardium

• ECG- can be normal, have inverted T waves or ST depression

• Troponins are elevated

STEMI

• Complete occlusion of the blood vessel lumen that results in transmural injury and infarct to the myocardium

• ECG- has hyperacute T waves or ST elevation

• Troponins are elevated

Acute Pericarditis

• Pericardial membranes become inflamed and roughened

• An exudate may develop

• Need 2 out of 4 symptoms: 1. chest pain, 2. pericardial rub, 3. ECG changes, 4. new pericardial effusion

Pericardial Effusion

• Accumulation of fluid in the pericardial cavity

• Can be serous, an exudate, serosanguineous (combination of serous and blood), sanguineous (blood)

Constrictive Pericarditis

• Fibrous scarring with occasional calcification of the pericardium, constricting the heart and reduces cardiac output

• Associated with radiation exposure, rheumatoid arthritis, uremia or coronary artery bypass graft

Acute Rheumatic Fever

• An inflammatory disease that results from a delayed immune response to a streptococcal infection

• May progress to rheumatic heart disease if severe or left untreated

Infective Endocarditis

• Inflammation of the endocardium

• Most common cause is staphylococcus aureus

Types of Shock

• Hypovolemic

• Cardiogenic

• Neurogenic

• Anaphylactic

• Septic

Systolic vs. Diastolic Left-sided Heart Failure

• Systolic- left ventricle loses its ability to contract normally

• Diastolic- left ventricle becomes stiff, impairs ability to relax between beats