Pathophysiology, Chp. 12 - Cardiovascular System Part 1

- arrythmias

- myocardial infarction (MI)

- infection

- pericarditis

a stethoscope.

It records the heart valve movements, blood flow and cardiac output. Provides useful information regarding valvular abnormalities, congenital defects, and changes in heart structure or function.

Assesses general cardiovascular function and checking for exercise-induced problems such as arrhythmias.

Measures pressure and assesses valve and heart function. It can determine central venous pressure and pulmonary capillary wedge pressure.

Visualizes the flow of blood in the coronary arteries.

Measures the levels of blood proteins (troponin). These proteins are released when cardiac muscle's been damaged.

The doppler is a microphone used to record sound of peripheral blood flow. Arterial blood gases checks the O2 levels (should be high) and acid-base balance.

arteriosclerosis or atherosclerosis.

- degeneration

- loss of elasticity

- wall becomes thick --> lumen gets narrower

- ^BP

Presence of atheroma (plaque) in large arteries.

1. Dietary modifications: decreases total fat intake, and reduces wait. Reduces salt intake (water follows salt, ^fluid leads to HTN and longterm can damage vessel).

2. Regular exercise program: helps lower serum lipid levels, and reduces stress.

3. Stop smoking: decreases risk of coronary disease.

Vasodilators: reduces peripheral resistance systematically, thus reduces the heart's workload. This provides better balance of oxygen supply and demand in the heart muscle.

Beta blockers: used to treat HTN and dysrhythmias.

Calcium channel blockers: blocks the movement of calcium ions into the cardiac and smooth muscle fiber. This decreases cardiac contractility, is a antihypertensive and works against angina.

Digoxin: used as treatment for heart failure. Slows the conduction of impulses and heart rate and increases the contractility of the heart.

Antihypertensive drugs: lowers bp to normal levels.

Adrenergic blocking drugs: can act as vasodilators; works on the SNS or on the periphery.

Inhibitors: used for treating patients with HTN and CHF. Blocks the conversion of angiotensin I to angiotensin II (powerful vasoconstricter).

Diuretics: induces the removal of fluid through urination. Removes excess water and sodium. Used to treat high bp and CHF.

Anticoagulants: "blood thinners", reduces the risk of blood clot formation.

Cholesterol-lowering drugs: prescribed when diet and exercise are ineffective in reducing blood levels. Reduces the low-density lipoprotein and cholesterol content of the blood by blocking synthesis in the liver.

Low-density lipoprotein (LDL): high lipid content, transports cholesterol from the liver to the cells. Major contributor to atheroma formation.

High-density lipoprotein (HDL): low lipid content, transports cholesterol from the cells to the liver to be catabolized and excreted. GOOD lipoprotein.

- weight loss

- ^ exercise

- reduce sodium intake

- control HTN

- stop smoking

- CABG

- coronary angioplasty

Chest pain that occurs when there's a deficit of O2 to the heart muscle.

Etiology:

- insufficient blood supply to heart (athero/arteriosclerosis)

- HTN

- myocardial hypertrophy

Precipitating factors: activities that increase the demands on the heart, usually triggered by a physical or emotional stress.

True.

A "heart attack" which is caused by lack of blood flow to the heart muscle --> necrosis.

False; there's a notably greater risk of a second MI, CHF or stroke occurring within a short time.

ST-elevation (STEMI) --> transmural damage, Q-wave present on ECG.

non-ST-elevation (NSTEMI) --> non-transmural, non-Q wave (no Q wave/normal) in the ECG, no ST elevation (likely a depression instead).

1. Thrombus from atheroma obstructing an artery.

2. Vasospasm occurring in the presence of partial occlusion from atheroma.

3. Part of thrombus may break away forming an embolues.

Collateral circulation which are small arteries opening up and carrying blood to the heart tissue instead. May reduce the size of an infarction.

- pressure, heaviness or burning in chest, especially with increased activity.

- sudden shortness of breath

- weakness

- fatigue

- pain; substernal, jaw, left arm or neck

- pallor

- diaphoresis

- dizziness

- changes in the ECG

- Serum enzymes released from necrotic cells (myosin and troponin)

- reduction of cardiac demand

- O2 therapy

- analgesics

- anticoagulants

- meds used for HTN, CHF and dysrhythmias

- cardiac catheterization

- sudden death

- cardiogenic shock; inability to pump enough blood due to impaired left ventricle --> hypoxia.

- CHF

- rupture of the necrotic tissue

- thromboembolism; from a thrombus that develops over the infarcted surface and eventually breaks off (embolus).

They're deviations from normal cardiac rate or rhythm.

- electrolyte imbalance

- fever

- hypoxia

- stress

- infection

- drug toxicity

True.

Marked by altering bradycardia and tachycardia, usually requires a mechanical pacemaker.

Premature atrial contractions or beats (PACs or PABs): extra contractions or ectopic beats of the atria. Palpitations fall under this category.

Atrial flutter: atrial heart rate of 160-350 bpm. The AV node delays conduction --> ventricular rate is slower.

Atrial fibrillation: 350 bpm. Causes pooling of blood in the atria and is treated with anticoagulants to prevent clotting and potential stroke.

When conduction is excessively delayed or stopped at the AV node.

Partial blocks:

- First-degree: conduction delay between atrial and ventricular contractions.

- Second-degree: periodically leads to a missed ventricular contraction.

- Third-degree: no transmission of impulses from the atria to the ventricles.

Bundle Branch Block: interference with conduction in one of the bundle branches. Usually doesn't alter cardiac output but appears in ECGs as a wide QRS wave.

Ventricular Tachycardia: reduce cardiac output; filling time is reduced and the force of contraction is reduced.

Ventricular Fibrillation: ineffective ejection of blood resulting in lack of cardiac output --> hypoxia and contraction ceases.

Premature Ventricular Contractions (PVCs): additional beats, usually not a concern. But increasing frequency can cause ventricular fibrillation --> cardiac arrest.

Sends an electric shock to the heart to disrupt the electrical activity that occurs with fibrillation.

No conduction of impulses, and the ECG shows a flat line. Lack of contractions --> no CO, deprives the brain and heart of O2. Loss of consciousness occurs immediately and respiration stops. No pulse at any site of the body.

- excess vagal nerve stimulation

- drug toxicity

- insufficient O2

- K imbalance

- blow to the heart

- Electric defib.

- AEDs

- CPR

A condition where the heart is unable to pump sufficient blood to meet the needs of the body. Usually occurs as a complication of another condition.

1. Systolic dysfunction: left ventricle loses its ability to contract normally. Heart can't pump with enough force.

2. Diastolic dysfunction: left ventricle loses its ability to relax normally (stiff muscle). Can't properly fill.

1. Cardiac output/stroke volume decreases: not enough blood reaching organs and tissues --> decreased cell function, fatigue and lethargy, mild acidosis (^respiration).

2. "Backup" congestion develops: output from the ventricle is than the blood coming in, causing congestion in the affected ventricle.

1. L.ventricle weakens and can't empty.

2. Decreased CO to system (decreased cell function).

3. Decreased blood flow to kidney stimulates renin-angiotensin and aldosterone secretion (^vasoconstriction --> ^bv and makes the heart work harder).

4. Normal volume of blood returning from the lungs can't enter the left side causing congestion in the pulmonary veins.

5. ^pressure --> pulmonary congestion or edema.

1. R. ventricle weakens can't empty.

2. Decreased CO output to system.

3. Decreased blood flow to kidney stimulates renin-angiotensin and aldosterone secretion (^vasoconstriction --> ^bv and makes the heart work harder).

4. Backup of blood into the system circulation (vena cava).

5. ^venous pressure --> edema in legs and liver and abdo. organs.

6. ^venous pressure (superior) --> distended neck vein and cerebral edema.

- decreased blood supply to tissues

- hypoxia (from lack of blood supply)

- fatigue and weakness

- shortness of breath (dyspnea)

- exercise and cold intolerance

- dizziness

- compensation mechanisms:

- tachycardia

- pallor

- dyspnea and orthopnea (difficulty breathing when laying down due to pulmonary congestion)

- cough (fluid irritating resp. passages)

- paroxysmal nocturnal dyspnea

- rales (bubbly sound in lungs)

- edema in feet, legs or buttocks

- ^pressure in jugular veins --> distention

- hepatomegaly and splenomegaly

- ascites (collection of fluid in abdo.)

An acute systemic inflammatory condition that result from an abnormal immune reaction occurring a few weeks after an untreated infection. The inflammation involves the heart and other parts like the joints and skin. Usually occurs in children 5-15 yrs of age.

Pericarditis: inflammation of the outer layer (pericardium), includes effusion (^fluid accumulation) --> impairs filling.

Myocarditis: myocardium, inflammation causes lesions in the heart muscle, may interfere with conduction.

Endocarditis: endocardium, affects the valves which form small wart-like vegetations along the edge of the valve cusps. Disrupts the flow of blood and effectiveness of the left ventricle.