Cardiopulm - Myocardial Vascular and Muscle Dysfunction

Myocardial vascular dysfunction includes

- CAD

- Myocardial ischemia

- Stangle angina

Myocardial muscle dysfunction includes

- Arrhythmias

- Valve disease

- Cardiomyopathy

- Heart failure

CAD is _ and _

Progressive; chronic

CAD is characterized by

Steady buildup of plaque in the coronary arteries

What is atherosclerosis

Buildup of cholesterol, lipid, cellular debris, and calcium plaques in medium sized and large arteries

Atherosclerosis in the heart can lead to

- CAD

- Acuter coronary syndrome

- MI

Atherosclerosis in the brain can lead to

CVA

What are the characteristics of stable plaque

- Slow accumulation of deposits

- Thick fibrous cap

- Unlikely to rupture

- More arterial narrowing

What are the characteristics of unstable plaque

- Rapid accumulation of lipid deposits

- Thin fibrous cap

- Prone to rupture

- Less arterial narrowing

Stable angina is

Predictable with certain exertion level or onset of physical or emotional stress

The key symptom of myocardial ischemia is

Stable angina

What are the chief complaints of stable angina

- Chest discomfort

- Provoked with exertion

- Alleviated with rest or nitroglycerin

- Not reproducible with palpation

Stable angina can be managed with

Sublingual nitroglycerin

What are the causes of stable angina

- Blood vessel is occluded by plaque or muscle spasm

• Oxygen demand outpaces supply

• Ischemia occurs as a result

• If sustained, infarction or cell death (necrosis)

occur

Acute coronary syndrome can be

- MI

- Unstable angina

What are the characteristics of MI

- Cell death damages or destroys heart tissue

- Damage often irreversible

- Occurs with prolonged or unmanaged ischemia

What are the characteristics of unstable angina

- Decreased blood flow to the heart

- Not severe enough to cause necrosis or MI

- Increases risk of MI

- Occurs at rest or below usual ischemic baseline

The duration of unstable angina is

>20 min

Unstable angina usually indicated

Progression of CAD

Unlike stable angina, unstable angina is

Unpredictable and may occur at rest

Unstable angina generally sees a deterioration of

A previously stable pattern

Myocardial ischemia can be caused by

Obstructed myocardial blood flow that can be due to partial or complete blockage

Myocardial ischemia can result in _ if blood flow is not restored

Permanent damage

What are the typical presentations of MI

- Chest pain, pressure, tightness, and squeezing

- May radiate to neck, jaw, shoulders, back, and arms

- Can be confused with heartburn or indigestion

- Pale

- Diaphoretic appearance

MI occurs due to

Prolonged or unmanaged ischemia

In MI, blood supply

Cannot keep up with demand

Cell death in MI is due to

Oxygen deprivation

During MI, cell death begins within

15 minutes of initial hypoxia

Complete necrosis following an MI occurs

>2-4 hours of sustained ischemia

The site and extent of a MI depends on

• Anatomic distribution of artery

• Function of collateral arteries

• Affects ability to reroute blood as necessary

• Presence and extent of prior MI

• Amount of myocardial demand

What occurs in the zone of infarction during a MI

- Tissues become necrotic due to cell death

- Extent of infarction depends on presence of additional lesions and collateral circulation

What occurs in the zone of injury during a MI

- Able to return to normal

- May become necrotic if blood flow is not restored

- May regain function within 2-3 weeks if collateral circulation is adequately functioning

The zone of ischemia will

Immediately surround the zone of injury

What are the different types of MI

- ST elevation

- Non-ST elevation

- Complicated

- Uncomplicated

What are the characteristics of ST elevation MI

• Anginal symptoms at rest

• Results in myocardial necrosis

• Identified by elevated cardiac enzymes with ST

segment elevation on EKG

• Troponin and Creatinine Kinase (CK) levels are elevated

• Complete artery blockage

What are the characteristics of Non-ST elevation MI

• Anginal symptoms at rest

• Results in myocardial necrosis

• Identified by elevated cardiac enzymes without

ST segment elevation on EKG

• Troponin and Creatinine Kinase (CK) levels are elevated

• Partial artery blockage

Complicated MI involves

• Dysrhythmia

• Damage to heart structuress

• Thrombosis

• Often leads to heart failure

Uncomplicated MI involves

- Small infarction

- Small recovery without significant decrease in cardiac output at rest or with min-mod activity

MI is diagnosed with

12 lead EKG and cardiac enzymes

What are the cardiac enzymes

- Troponin

- Myoglobin

- Creatine kinase

Troponin is released only when

Necrosis occurs

What are the presentations of elevated troponin

• Serum levels increase within 3-12

hours from onset of angina

• Levels peak at 24-48 hours

• Return to baseline over 5-14 days

Myoglobin is released with

Any damage to muscle tissue, including necrosis

What are the typical presentations of myoglobin increase

• Increase in serum level within 30-60

min after injury occurs

• Levels peak within 4 to 12 hours

• Immediately returns to baseline

levels

Creatine kinase has different subtypes depending on

Type of tissue

What are the typical presentation of CK increase

Increase in serum level within 3-12

hours from onset of angina

• Levels peak within 24 hours

• Return to baseline after 48-72 hours

The main cardiac enzymes that are looked at to rule in MI are

Troponin and CK

What are treatment goals of myocardial vascular dysfunction

- Treat underlying causes

- Address dietary factors

- Pharmacologic mangement

- Exercise training and/or cardiac rehab

Modifiable risk factors of CAD includes

- Hyperlipidemia

- HTN

- Smoking

- Overweight/obesity

- Sedentary lifestyle

- Diabetes

CAD begins to increase at age _ in men and age _in women

45; 55

Men tend to have heart attacks

Earlier in life

Estrogen provides a _ effect in women

Protective

Pharmacologic treatment aims to

Decrease O2 demand and increase O2 supple

What pharmacologic options decrease O2 demand

- Beta blockers

- Ca channel blockers

- Nitrates

What pharmacologic options increase O2 supply

- Vasodilators (nitrates and Ca channel blockers)

- Thrombolytics

- Anti-platelets

- Anti-coagulants

The transtheoretical model of behavior change is composed of which parts

- Precontemplation

- Contemplation

- Preparation

- Action

- Maintenance

- Termination (habit)

What diagnostic tests can be used for CAD

- EKG

- Echocardiogram

- Angiogram

- Nuclear stress test

- Nuclear PET scan

An echocardiogram tests for

Valve function, ventricular wall motion, and estimates of SV and EF

An angiogram is used for

Visualizing coronary arteries or open narrowed/blocked arteries

A nuclear stress test evaluates

Myocardial perfusion at rest, during exercise, or pharmacologically induced stress

A nuclear PET scan evaluates

Myocardial perfusion and tissue function

Myocardial valve disease includes

- Stenosis

- Regurgitation/insufficiency

- Prolapse

Myocardial stenosis is characterized by

The valve being unable to open fully due to thickening, stiffness, or fusing together

In myocardial stenosis, forward blood flow is

Obstructed

In stenosis, the chamber attempting to pump blood through a stenotic valve becomes

Hypertrophied

In regurgitation, the valves

Do not close fully or blood leaks backward as the valve is closing

Regurgitation causes increased

Work to pump the same amount of blood

In a prolapse, the valves

Do not close smoothly or evenly

Prolapse causes the valves to bulge into the

Atrium

Prolapse is caused by

- Tissue abnormalities

- Rupture of papillary muscles or chordae tendinae

Cardiomyopathy is caused by

Disease of the heart muscles

Disease of the heart muscles that lead to cardiomyopathy include those that cause

- Dilation

- Hypertrophy

- Restriction

Prolapse eventually causes

Increased compliance of the chamber that is being overfilled

Dilated cardiomyopathy is chracterized

Ventricle walls becoming stretched out

Dilated cardiomyopathy (DCM) results in

Significant systolic dysfunction

Hypertrophic cardiomyopathy is characterized by

Thickened ventricular myocardium decreasing available space inside ventricle

Hypertrophic cardiomyopathy reults in

Decreased filling during diastole

Restrictive cardiomyopathy is characterized by

Endocardial scarring of ventricles

Restrictive cardiomyopathy results in

Decreased fulling during diastole AND decreased force during systole

Scar tissue resulting from restrictive cardiomyopathy decreases

Compliance and contractility

Heart failure is the final pathway of

Myocardial dysfunciton

Classification of cardiac failure is based on

- Stage/severity/compensation

- Side of heart involved

- Cardiac output

- Duration

- Type of function affected

Left sided heart failure is characterized by

Fluid of the L ventricle backing up into the lungs

L sided heart failure causes

Pulmonary edema

What are key findings of L sided heart failure

• Dyspnea on Exertion

• Orthopnea

• Restlessness

• Tachycardia

• Pulmonary Congestion (cough, crackles,

wheezes, etc.)

In R sided heart failure

The right ventricle cannot produce enough force to overcome pulmonary pressure

In R sided heart failure, fluid in the R side of the heart backs up in

The venous system

R sided heart failure results in

Peripheral edema

What are the key findings of R sided heart failure

• Lower extremity edema

• Abdominal swelling (ascites)

• Jugular venous distention (JVD)

• Increased peripheral venous pressure

• Fatigue

R sided heart failure usually results from

L sided heart failure

R sided heart failure is also referred to as

Cor Pulmonale

Diastolic heart failure results in _ ejection fraction

Preserved

Systolic heart failure results in _ ejection fraction

Reduced

In diastolic heart failure, the ventricles

Lose the ability to relac and expand

During diastolic heart failure, the heart cannot

Fill with enough blood

In systolic heart failure, the ventricles

Lose the ability to contract and pump blood

During systolic heart failure, the heart cannot

Pump enough blood

In congestive heart failure

The heart cannot continue pumping blood forward, causing fluid back up in the venous system of the lungs or peripheral circulation

Left sided congestive heart failure is characterized by

Inability to pump enough oxygen rich blood supply to the periphery

Right sided congestive heart failure is chracterized by

Inability to pump enough blood to lungs to pick up oxygen