Cardiopulm Unit 5 Cardiac Pathologies: Cardiac Muscle Dysfunction

Question 1

What is Cardiac Muscle Dysfunction (aka “Heart Failure”)?

Answer 1

Forward output of blood by the heart is insufficient to meet the metabolic needs to the body

• A syndrome with a variety of interrelated pathophysiologic phenomena of which impaired ventricular function is the most important
• Results in a reduction of exercise capacity and other characteristic clinical manifestations

Question 2

With the Etiologies of Congestive Heart Failure, one of the causes is Hypertension. What is the Description of this?

Answer 2

Increased arterial pressure leads to left ventricular hypertrophy (increased myocardial cell mass) and increased energy expenditure

Question 3

With the Etiologies of Congestive Heart Failure, one of the causes is Coronary Artery Disease (Myocardial Ischemia). What is the Description of this?

Answer 3

Dysfunction of the Left or Right ventrical, or both as a result of injury. Scar formation and decreased contractility may occur as well as reduced relaxation

Question 4

With the Etiologies of Congestive Heart Failure, one of the causes is Cardiac Dysrhythmias. What is the Description of this?

Answer 4

Extremely rapid or slow cardiac arrhythmias impair the functioning ventricles. Dysfunction may be reversible if arrhythmias controlled

Question 5

With the Etiologies of Congestive Heart Failure, one of the causes is Cardiomyopathy. What is the Description of this?

Answer 5

Contraction and relaxation of myocardial muscle fibers are impaired. Primary causes: pathologic process in the heart muscle itself, which impairs the hearts ability to contract. Secondary causes: systemic disease process

Question 6

With the Etiologies of Congestive Heart Failure, one of the causes is Heart Valve Abnormaility. What is the Description of this?

Answer 6

Valvular stenosis or imcompetent valves cause myocardial hypertrophy and cause a decrease in venticular distensibility with mild diastolic dysfunction

Question 7

What is Hypertensive Heart Disease?

Answer 7

A condition that relates to structural changes that occur in the heart as a response to chronic afterload changes that are implied by increased BP

Question 8

With Hypertensive Heart Disease, what can cause Left Ventricular Hypertrophy?

Answer 8

• Hemodynamic load/stress
• Age, gender, genes, birth weight
• Salt intake, catecholamines, Angiotension II, Aldosterone

Question 9

WIth Hypertensive Heart Disease, what can Left Ventricular Hypertrophy result in?

Answer 9

• Myocardial Ischemia (which can lead to infarction, then CHF)
• Impaired contractility (can lead to CHF)
• Impaired left ventricular filling (can lead to CHF)
• Atrial Fibrillation, Ventricular Arrhythmias (can lead to thromboembolism sudden death

Question 10

What is Primary Cardiomyopathies?

Answer 10

Generally idiopathic or genetic in nature, involve pathologic processes in the heart muscle itself (often in the mitochondria) which impair the heart’s ability to contract

Question 11

What is Secondary Cardiomyopathies?

Answer 11

The result of another underlying condition or external factor affecting heart muscle function. Can be classified according to the systemic disease that subsequently affects myocardial contraction (e.g., excessive alcohol consumption can lead to alcoholic cardiomyopathy)

Question 12

What is Dilated Cardiomyopathy?

Answer 12

This is when the ventricals of the heart are enlarged, without hypertrophy. However there is not enough muscular capacity to pump out the blood, decreases cardiac output

Inotropic meds are used with this to increase contractility

Question 13

What is Hypertrophic Cardiomyopathy?

Answer 13

When the walls of the Ventricles thicken and become stiff. CO will decease, because there is impaired filling and contractility and there is less blood supply. Arrythmias may present with this as well

Question 14

What is Restrictive Cardiomyopathy?

Answer 14

When the walls of the ventricles become stiff, but not nessessarily thickened; this will affect systoli and diastoli

Question 15

How are Cardiomyopathies distinguished from one another?

Answer 15

By electrocardiographics and myocardial biopsy results

Question 16

What is Heart Failure Systolic Dysfunction? What are some causes?

(Systolic is when heart contracts)

Answer 16

This is impaired cardiac contractile function

Causes:
- Ischemic Heart disease (MI, Transient/persistent myocardial ischemia)
- Dilated Cardiomyopathy (Idiopathic, viral, genetic, alcohol, etc){over enlarged ventricles, not enough myocardium}
- Valvular Heart Disease (Aortic/Mitral valve stenosis or regurgitation)

Question 17

What is Heart Failure Diastolic Dysfunction? What are some causes?

(Diastolic is when heart fills)

Answer 17

Impaired filling of the left or right ventricle due to hypertrophy and/or changes in the composition of the myocardium

Causes:
- Left Ventricular Hypertorphy (e.g., as a result of chronically increased afterloads in HTN)
- Restrictive Cardiomyopathy
- Myocardial Fibrosis
- Pericardial Effusion or Tamponade

Question 18

With Hear Failure, what is the difference between HFrEF and HFpEF?

Answer 18

Due to significant overlap between systolic and diastolic dysfunction (i.e. many patients with HF suffer from both), it is common to categorize patients into having either:
- Heart Failure with reduced ejection fraction (HFrEF)
-< 40% EF
- Heart Failure with preserved ejection fraction (HFpEF)
-> 50% EF

This type of categorization is:
- useful, in part, because of the widespread availability of methods to measure LVEF (e.g., echocardiography)
- used as a variable in many clinical HF trials
- useful within medical management of individuals with HF

EF = Systolic / End-Diastolic volume (review)

Question 19

What are the physiological responses to Decreased Cardiac Output?

Answer 19

• Increase/Activation of Sympathetic Nervous System
• Increased Renin-Angiotensin System

Also Increase in Antidiuretic Hormone (not as important for class)

Question 20

When there is a decrease in CO, why is there activation of the sympathetic nervous system and renin-angiotensin system?

Answer 20

In order to:
- Increase myocardial contractility and HR
- Produce arterial vasoconstriction (to help maintain arterial pressure)
- Produce venous constriction (to increase venous pressure)
- Increase blood volume (to increase preload/ventricular filling)

Question 21

With Decreased CO, what is the affect of Increased activity in the Sympathetic Nervous System? What may happen over time?

Answer 21

This will stimulate myocardial contractility, HR, and arterial/venous tone which results in an increase in central blood volume which serves to further elevate pre-load (to attempt to elevate CO).
- Over time though, the heart becomes insensitive to B-adrenergic stimulation, which results in a decreased force of myocardial contraction and an inability to attain higher heart rates during physical exertion

Question 22

How does a decrease in CO affect the Renal System? What is the affect of the RAAS being activated?

Answer 22

Declining CO causes a reduction in renal blood flow and glomular filtration rate, which leads to sodium and fluid retention
- RAAS activation leads to further increases in peripheral vascular resistance and left ventrical after-load as well as sodium retention (pretty much making everything worse)

Question 23

Using the graph as a representation, What happens when there is Chronic Sympathetic activation?

Answer 23

This leads to a blunted respons, weaker myocardial contractions, and limited HR increases during stress.
- The heart now operates under curve C contraints, unable to meet increased demands, signifying the progression of Heart Failure due to desensitization to sympathetic stimulation

Question 24

Using the graph, what does the Normal Curve represent?

Answer 24

As the LVEDP (preload) increases, the stroke volume also increases, up to a certain point. This is due to the heart muscle fibers being optimally stretched, leading to a more forceful contraction due to the Frank-Starling Mechanism

Question 25

Using the graph, what does the Mild Dysfunction curve represent?

Answer 25

The curve is flatter and indicates that the heart with mild dysfunction has a reduced response to increased preload. The heart still response with increased stroke volume as preload increases, but not as effectively as a normal heat

Question 26

Using the graph, what does the Severe Dysfunction curve represent?

Answer 26

This curve is much flatter and indicates that increases in preload result in even smaller increases in stroke volume. The heart is significantly less responsive to changes in preload, reflecting a limited ability to enhance its contraction in response to increased filling. - **Eventually the increases in preload may even lead to a decrease in stroke volume**

Question 27

What happens has Cardiac Dysfunction worsens? With this we should monitor...

Answer 27

- The heart becomes less and less able to tolerate the increases to afterload/systemic vascular resistance that aims to maintain arterial pressure - We should monitor: -Fluid Status: reduced sensitivity to preload impairs the hearts ability to pump efficiently, leading to fluid retention as the kidneys compensate for perceived low blood volume -Conditions that create excessive afterload such as unmanaged hypertension which can place additional strain on the heart, exacerbating myocardial workload and potentially worsening heart failure.

Question 28

What commonly causes Left-Sided Heart Failure?

Answer 28

- CAD with ischemic LV damage (i.e., acute MI) - Chronic HTN - Dilated Cardiomyopathy - Valvular hear disease with its pressure and/or volume overloading the heart

Question 29

What commonly causes Right-Sided Heart Failure?

Answer 29

- Left-sided heart failure where there is an uncompensated left ventricular pressure that leads to elevated pulmonary vascular pressures and then stress onto the right-ventricle -This is considered “**Biventricular Failure**” - Diseases of the lung parenchyma or pulmonary vasculature (e.g. COPD, interstitial lung diseases, lung infection, pulmonary embolism) -When right-sided heart failure is resultant of pulmonary processes, it is known as **cor pulmonale**

Question 30

What increases Dyspnea/Increased work of Breathing?

Answer 30

- Increased pulmonary venous pressure can lead to a transudation of fluid into the alveoli (**pulmonary edema**) and pulmonary interstitium (making the lungs soggy and difficult to move) which both ultimately increase the work of breathing. - The reduced blood flow to overworked respiratory muscles (i.e.., because of decreased cardiac output) and accumulation of lactic acid may also contribute to sensation of dyspnea.

Question 31

What do Pulmonary Crackles/rales result from?

Answer 31

- Results from elevated pulmonary venous and capillary pressures and transudation of fluid into alveolar spaces - Frequently heard at both lung bases but may extend upward, depending on the patient’s position, the severity of CHF, or both

Question 32

What is Orthopnea?

Answer 32

Sensation of dyspnea or observation of labored breathing while lying flat which is relieved by sitting up

Question 33

What is Orthopnea caused by?

Answer 33

- Caused by the redistribution of blood from the gravity-dependent portions of the body (e.g. abdomen and LEs) towards the lungs that increases venous return and **work on the heart**. - Can be described by number of pillows on which the patient sleep on to avoid breathlessness (e.g. 3-pillow orthopnea). - In severe cases, individuals end up preferring to sleeping in sitting on a recliner.

Question 34

What is Paroxysmal Nocturnal Dyspnea?

Answer 34

Severe breathlessness that awakens the patient from sleep 1-3 hours after lying down

Question 35

What does Parixysmal Nocturnal Dyspnea result from?

Answer 35

- Results from the gradual reabsorption into the circulation of LE interstitial edema after lying down and increase in venous return/load on heart. - A nocturnal cough may also occur for similar reasons

Question 36

# Extra Heart Sounds What does a S3 Heart Sound (aka Ventricular Gallop) indicate?

Answer 36

- Indicates a very compliant left ventricle. Thought to occur as blood passively fills a quickly distending left ventricle that makes contact with the chest wall during early diastole. - May be normal (“physiologic S3”), particularly in young people, but in the presence of other indicators of heart disease, it is one of the **most sensitive** indicators of significant ventricular dysfunction

Question 37

# Extra Heart Sounds What does a S4 Heart Sound (aka Atrial Gallop) indicate?

Answer 37

- Represents “vibrations of the ventricular wall during the rapid influx of blood during atrial contraction” from an exaggerated atrial contraction. It is found in diseases with ventricles so thick to require a strong atrial contraction. As it is related to atrial systole, this sound is appreciated in late diastole. * Unlike S3, this extra heart sound is almost always abnormal.

Question 38

# Decreased Exertional Tolerance Patients with cardiac muscle dysfunction, depending on the severity may display with what?

Answer 38

* **A more rapid heart rate** rise during any submax workload * A flat, blunted, and **occasionally hypotensive** (decrease) response in SBP during exercise * A **lower max/peak oxygen consumption** (VO2) * ECG signs of **myocardial ischemia** * More easily provoked **dyspnea** and **fatigue**

Question 39

What is Jugular Venous Pressure/Distension an indication of?

Answer 39

**An indication of increased volume in the venous system and may be an early sign of right-sided heart failure**

Question 40

What does Peripheral Edema reflect?

Answer 40

- Reflects increased venous pressures due to retrograde movement of fluid from heart chambers and fluid retention by kidneys after the pressoreceptors of the body sense a decrease in volume of blood (due to pump failure/drop in cardiac output). * Mostly collects around ankles and feet.

Question 41

What is a 1+ on the Pitting Edema Scale?

Answer 41

Barely perceptible depression (pit)

Question 42

What is a 2+ on the Pitting Edema Scale?

Answer 42

Easily identified depression; skin rebounds to its original contour within 15 seconds

Question 43

What is a 3+ on the Pitting Edema Scale?

Answer 43

Easily identified depression; skin rebounds to its original contour within 15-30 seconds

Question 44

What is a 4+ on the Pitting Edema Scale?

Answer 44

Easily identified depression; skin rebounds to its original contour within > 30 seconds

Question 45

What are Sx of Left heart Failure?

Answer 45

*Breathing Signs* - Dyspnea and increased WOB - Orthopnea - Paroxysmal Noctornal Dyspnea (PND)

Question 46

What are the Physical Findins of Left Heart Failure?

Answer 46

- Diaphoresis - Tachycardia/Tachypnea - Pulmonary Rales - S3/S3 (extra) heart sounds

Question 47

What are Physical Findings of Right heart Failure?

Answer 47

- Jugular Venous Distension - Peripheral Edema

Question 48

What are Sx of Right heart Failure?

Answer 48

*systemic signs* - Anorexia - Right Upper Quadrant Discomfort (because of hepatic enlargement)

Question 49

What is Heart Failure Exacerbation/Decompensation?

Answer 49

The presence of new or worsening signs/symptoms of dyspnea, fatigue, or edema that lead to hospitalization or unscheduled medical care (doctor visits or emergency department visits) **- This Typically requires hospitalization**

Question 50

With Heart Failure Exacerbation/Decompensation, what are the S/S?

Answer 50

* Dyspnea at rest * Unrelieved Angina * Wheezing or chest tightness at rest * Paroxysmal nocturnal dyspnea: requiring to sit in chair to sleep * Weight gain or loss of more than 5 lbs in 3 days * Confusion * Pulmonary Crackles * S3 Heart Sound * Jugular Venous Distention

Question 51

With, Heart Failure Exacerbation/Decompensation what are common Test and Procedures that will be used?

Answer 51

- Chest X-rays - Echocardiograms - Invasive monitoring of cardiovascular performance -Arterial lines -Central lines (e.g., Pulmonary Artery Catheterization)

Question 52

What are the benefits of Chest X-rays?

Answer 52

Assist in the clinical dx and monitoring of the progression or regression of: *Airspace consolidation *Large intrapulmonary air spaces and presence of mediastinal or subcutaneous air *Lobar atelectasis *Other pulmonary lesions *Rib Fractures * Determine proper placement of medical equipment (e.g., ET tube, central lines, etc.) * Evaluate structural features such as cardiac or mediastinal size and diaphragmatic shape and position

Question 53

What are the benefits of using an Echocardiogram?

Answer 53

Echocardiograms give information regarding: * Size of cavities * Thickness, integrities, and motions of walls and septa * Functioning of the valves ## Footnote Adding Doppler analysis is useful in assessing the hemodynamic significant of cardiac structural disease

Question 54

What are Specific Question with Heart Failure?

Answer 54

1. Is the LVEF preserved or reduced? 2. What is the structure of the LV (hypertrophy, dilated, normal)? 3. Are other structural abnormalities present (pericardial, valvular functioning, right ventricle) that would affect LV functioning?

Question 55

What is the purpose of the Arterial Catheters?

Answer 55

- Directly and continuously record systolic, diastolic, and MAP * The MAP is useful clinically because it yields one number that relates to cardiac output and systemic vascular resistance. * **A MAP of less than 60 mm Hg may indicate inadequate tissue perfusion** * Repeat blood samples * Deliver meds

Question 56

With Arterial Catheters, what happens if the transduce is too high or low?

Answer 56

- If too low, BP will read high - If too high, BP will read low

Question 57

What happens if the A-line is dislodged? What are major comlications associated with arterial lines?

Answer 57

- If A-Line is dislodged, apply firm pressure and immediately notify RN - Major complications are: -Bleeding -Infection -Lack of blood flow to the tissue supplied by the artery

Question 58

What are the indications of using Pulmonary Artery Catheter (Swan Ganz Catheter)?

Answer 58

- Evaluate volume status - Evaluate cardiac function - Guide medical therapy - Monitor response to fluids, diuretics, vasoactive drugs - Monitor high risk patients perioperatively

Question 59

What are some Interventions related to Acute and/or Chronic muscle Dysfunction?

Answer 59

- Pharm.: Diuretics, ACEI, ARBs, B-Blockers, etc - Dietary changes and nutritional supplementation (e.g., DASH diet) - Intra-Arotic Balloon Pump (usually with 2 insertions: Fem. Artery and Left axillary/subclavian) - Surgical management: Valvular Interventions, Left ventricular assistive device, etc.

Question 60

What is the Intra-Aortic Balloon Pump (IABP)?

Answer 60

Mechanical device that is used to temporarily support the heart's function in patients with severe heart failure, particularly those with cardiogenic shock or during high-risk cardiac procedures

Question 61

With the Intra-Aortic Balloon Pump, what happens during inflation?

Answer 61

The balloon inflates during diastole, which is when the heart is at rest and the coronary arteries are filling with blood. The inflation of the balloon **increases the aortic pressure during diastole, improving coronary artery perfusion and thereby oxygen delivery to the heart muscle**

Question 62

With the Intra-Aortic Balloon Pump, what happens during Deflation?

Answer 62

The balloon deflates just before systole, when the heart is about to contract. This deflation creates a vacuum effect that **reduces the afterload, making it easier for the heart to pump blood out into the body**.

Question 63

With Intra-Aortic Balloon Pump, what are the PT considerations with Femoral Artery Insertion (May vary with hospital rules/regulations)?

Answer 63

* No hip flexion is allowed in that LE. No HOB > 30 degrees. This is to prevent migration of catheter. You can log roll the patient. * Overall patients on bed rest (no OOB activity allowed). Check for bed sores, and monitor pulmonary hygiene * Once removed, typical protocols call for continued bed rest for ~8 hrs without LE therex (to prevent bleeding). After this period pt may need ROM/strengthening

Question 64

With Intra-Aortic Balloon Pump, what are the PT considerations with Left Axillary/Subclavian?

Answer 64

OOB activity allowed and encouraged (with hemodynamic monitoring)

Question 65

Why are Valvular Interventions useful?

Answer 65

Valvular interventions can be used to manage heart failure by repairing or replacing diseased heart valves that contribute to the heart's dysfunction

Question 66

# Valvular Interventions What is Percutaneous Balloon Valvuloplasty or Valvulotomy?

Answer 66

Minimally invasive via femoral artery access with balloon- mediated dilation procedure similar to PTCA

Question 67

# Valvular Interventions What is Annuloplasty?

Answer 67

Replacement of valve ring (annulus), or rim, of mitral and/or tricuspid valves, which can get torn when the valve prolapses from prolonged insufficiency or from the chordae tendinae becoming overstretched and starting to tear away from the ring

Question 68

# Valvular Approach With Median Sternotomy, what valves are accessed through this?

Answer 68

This is for the Aortic, Mitral or Tricuspid valve ## Footnote Also used for Coronary Bypasss

Question 69

# Valvular Approach With Right Anterior Thoracotomy, what valves are accessed through this?

Answer 69

Mitral or Tricuspid ## Footnote Also used for Coronary Bypasss

Question 70

# Valvular Approach With Upper Hemi-Sternotomy, what valves are accessed through this?

Answer 70

Aortic valve ## Footnote Also used for Coronary Bypasss

Question 71

# Valvular Approach With Lower Hemi-Sternotomy, what valves are accessed through this?

Answer 71

Mitral or Tricuspid ## Footnote Also used for Coronary Bypasss

Question 72

What is Ventricular Assist Device?

Answer 72

- Augments pumping ability of right, left, or both ventricles *Most common device is LVAD *Bridge to recovery *Bridge to transplantation *Destination therapy

Question 73

# (FITT recommendations) What is the ACSM guideline for Aerobic Exercise for Individuals with Heart Failure?

Answer 73

**F**: Minimally 3 days per week; preferably up to 5 days per week **I**: **Start at 40 to 50% and progress to 70-80% VO2 reserve (HRR)** **T**: Progressively increase to 20-60min a day **T**: Aerobic exercise: focusing on treadmill or free-walking and stationary cycling as capable

Question 74

# (FITT recommendations) What is the ACSM guideline for Resistance Exercise for Individuals with Heart Failure?

Answer 74

**F**: 1-2 nonconsecutive days **I**: **Begin at 40% 1RM for Upper Body and 50% 1RM for Lower Body**. Gradually increase to 70% 1RM over several weeks to months **T**: 1-2 sets of 10-15 reps focusing on major muscles **T**: Weight machines, dumbells, elastic bands and/or body weight can be used