Week 2 - Cardiovascular system Flashcards
Coronary Artery Disease
Starts with damage to the epithelium, damage results in inflammatory process. Cholesterol binds to the damaged area, macrophages attach to try to break down plaque that shouldn’t be there then they die, cap forms over the top to contain it. This narrows the coronary artery disrupting blood flow to the heart.
Increases risk for thrombus and MI.
Stable angina pectoris
Chest pain that is “stable” or predictable. Happens regularly with exercise but never at rest.
Unstable angina
Plaque deposits in the coronary artery rupture and exposes necrotic WBC and cholesterol to the blood. Platelets bind to the damaged area resulting in a thrombus. The thrombus can wave back and forth with blood flow looking flow through the vessel intermittently. Can have chest pain at rest.
Thrombus
Blood clot
Thrombosis
Clot that blocks a blood vessel
Embolization
Anything that obstructs an artery, typically a thrombus or air
Preload
The amount of stretch of the ventricles exhibit at the end of ventricular filling. More volume=more stretch.
Causes of decreased preload
- Hemorrhage
- Cardiac tamponade
- Dehydration
Cardiac Tamponade
Compression of the heart by an accumulation of fluid in the pericardial sac
Cardiac output
The amount of blood the heart pumps out in 1 minute.
CO= HRxSV
Cor pulmonale
Right ventricular failure secondary to pulmonary hypertension.
- Increased vascular pressure (after load)
- Increased ejection force of the R ventricle
- Decreased RV EF
- Increase in blood remaining in RV
- Inability of the RA to eject the same amount of blood into the RV
- Increase in blood remaining in the RA
- Increased atrial preload
- Blood backs up into SVC & systemic veins
- jugular distention and R side HF
- Increased blood to the liver and spleen causes hepatosplenomegaly
- Increased BP forces fluids out of circulation and into the tissues causing peripheral edema.
- Increase pressure to L side of the heart.
Stroke Volume
The volume of blood pumped out of the left ventricle during each systolic cardiac contraction
Afterload
The force (load) with which the heart muscle must contract agains in order to pump blood. For example systemic vascular resistance.
Causes of Cor Pulmonale
- Pulmonary disease resulting in pulmonary hypertension (most common)
- RV MI
- RV hypertrophy
- Tricuspid valve damage
- Secondary to L HF
High Output Heart Failure
Inability of the heart to pump enough blood to meet the circulatory needs of the body despite normal blood volume and cardiac contractility. Anemia impairs oxygen delivery to the tissues.
Causes of High Output Heart Failure
- Nutritional deficiencies (thiamine) causing decreased function and output.
- Hyperthyroidism, fever, sepsis
- increase basal rate, increase oxygen demands, not enough 02 causes hypoxia
Compensated Heart Failure
The heart dries to compensate and the SNS is activated which stimulates increased heart rate (faster) and increased stroke volume (harder). Preload is increased and the heart needs more oxygen which isn’t available. Heart cells start to die off. To compensate for dead cells the remaining cells bulk up to maintain CO, they also need more oxygen and start to die off. Heart chambers become smaller due to hypertrophy
Decompensated Heart Failure
- Overuse of the SNS means receptors are lost and there is a lowered response.
- Increased preload causes cell death and lack of oxygen
- Hypertrophy causes cell death due to lack of oxygen.
Four Stages of Heart Failure
Stage A - no limit on physical activity, no HF symptoms
Stage B - Slight limit on physical activity, activity results in symptoms
Stage C - Clinical development of Heart Failure
Stage D - No physical activity without symptoms, symptoms at rest.
Sounds of Aortic Regurgitation
- Early diastolic murmur, high pitched at left sternal border
- Diastolic rumbling at apex
- Systolic crescendo-decrescendo at left upper sternal border
Sound of Aortic stenosis
Mid systolic crescendo-decrescendo murmur with an S4 gallop
Sound of Mitral regurgitation
Blowing, pan-systolic murmur
Sound of mitral stenosis
Rumbling, decrescendo murmur at apex of the heart
Aortic Stenosis
Tight aortic valve resulting in blood backing up into the left ventricle and poor perfusion of body tissues.
Aortic stenosis is caused by
- Bicuspid aortic valve - genetic, two valves instead of three
- Age related calcification
- Rheumatic fever
Aortic regurgitation
When the aortic valve becomes floppy allowing blood back from the aorta into the ventricle when filling
Causes of Aortic Regurgitation
- Aneurysm of the aortic annuals (tissue and valve)
- Endocarditis - vegetation on the valve
- Rheumatic fever
Mitral valve regurgitation
Floppy mitral valve allowing fluid to backup into the pulmonary system and lungs.
Mitral valve
Valve between the left atria and ventricle
Tricuspid valve
Valve between the right atrium and right ventricle
Aortic valve
Valve between the left ventricle and aorta
Pulmonary Valve
Valve between the right ventricle and pulmonary artery.
Causes of mitral valve regurgitation
- Anything that leads to left ventricle dilation including:
- remodeling post MI
- dilated cardiomyopathy
- papillary muscle dysfunction
- chordae tendonae
Mitral valve prolapse
Mitral valve bulges into the left atrium (like an aneurysm)
Causes of mitral valve prolapse
- Idiopathic (unknown cause)
- Secondary to connective tissue disorder
Mitral valve stenosis
Tightened mitral valve
Causes of mitral valve stenosis
- Rheumatic fever
- Endocarditis (inflammation/infection of mitral valve)
