SM 138a - Heart Failure Physiology

Question 1

This graph represents grade _____ diastolic dysfunction.

How do you know?

What other indications might be present?

Answer 1

This graph represents grade I (mild) diastolic dysfunction.

• Small E wave (E/A ration <1)
  
  • Impaired ventricular relaxation = slow early filling
  • E’ velocity is decreased
• In addition, LA size and pressure will be normal to increased

Question 2

Describe the symptoms of left-sided heart failure

Answer 2

• Dyspnea
• Orthopnea
• Paroxysmal nocturnal dyspnea
• Fatigue
• Diaphoresis
• Tachycardia
• S3 (Systolic)
• S4 (Diastolic)

Question 3

A patient with symptoms and underlying structural heart disease has stage ___ heart failure

Answer 3

A patient with symptoms and underlying structural heart disease has stage C heart failure

Question 4

Eccentric hypertrophy is associated with ______ heart failure,

while concentric hypertrophy is associated with ________ heart failure

Answer 4

Eccentric hypertrophy is associated with systolic heart failure,

while concentric hypertrophy is associated with diastolic heart failure

Question 5

HF_EF is associated with systolic dysfunction,
while HF_EF is associated with diastolic dysfunction

Answer 5

HF_r_EF is associated with systolic dysfunction,
while HF_p_EF is associated with diastolic dysfunction

Question 6

Describe key features of eccentric hypertrophy

Cause:

Organization of sarcomeres:

Effect:

Answer 6

• Cause
  
  • ​Volume overload
• Organization of sarcomeres
  
  • New sarcomeres are created in series with existing sarcomeres
  • Myocyte elongation
• Effect
  
  • Dilation of the ventricle
  • Increased wall stress
  • Systolic dysfunction
  • Mitral regurgitation

Question 7

Describe Class I heart failure (NYHA)

Answer 7

No symptoms

Question 8

How would you expect wall thickness to change in systolic heart failure?

Diastolic heart failure?

Answer 8

Systolic: Decreased wall thickness

Diastolic: Increased wall thickness

Question 9

A patient with no symptoms has class ___ heart failure (NYHA)

Answer 9

A patient with no symptoms has class I heart failure (NYHA)

Question 10

How would you expect end diastolic volume to change in systolic heart failure?

Diastolic heart failure?

Answer 10

Systolic: EDV increases

Diastolic: Normal EDV (but most likely with increased pressure)

Question 11

Initially, neurohormonal activation helps patients with heart failure compensate for low CO by increasing BP.

In general, how can these compensatory mechanisms cause heart failure to worsen?

Answer 11

• Vasoconstriction (initially compensatory)
  
  • Causes increased afterload
    
    • Worse cardiac output
• Angiotensin II, Alsosterone
  (initially compensatory to retain fluid)
  
  • Leads to cardiac fibrosis
  • Adverse remodeling
    
    • Eccentric hypertrophy -> Dilation of LV
    • Concentric hypertropy -> Increased LV wall thickness

Question 12

Which extra heart sound is likely present if there is diastolic dysfunction?

Answer 12

S4

Question 13

A patient who gets symptoms with major exertion has class ____ heart failure (NYHA)

Answer 13

A patient who gets symptoms with major exertion has class II heart failure (NYHA)

Question 14

Patients with ejection fraction less than ____ most likley have HFrEF

Answer 14

Patients with ejection fraction less than 40-45% most likley have HFrEF

Question 15

Describe key features of eccentric hypertrophy

Cause:

Organization of sarcomeres:

Effect:

Answer 15

• Cause
  
  • ​Volume overload
• Organization of sarcomeres
  
  • New sarcomeres are created in series with existing sarcomeres
  • Myocyte elongation
• Effect
  
  • Dilation of the ventricle
  • Increased wall stress
  • Systolic dysfunction
  • Mitral regurgitation

Question 16

A patient who has symptoms at rest has class ___ heart failure (NYHA)

Answer 16

A patient who has symptoms at rest has class IV heart failure (NYHA)

Question 17

A patient experiencing heart failure has an initial compensatory neurohormonal response, initiated by the activation of ___________

Answer 17

A patient experiencing heart failure has an initial compensatory neurohormonal response, initiated by the activation of Baroreceptors

Question 18

A patient with no symptoms but increased risk factors has stage ___ heart failure

Answer 18

A patient with no symptoms but increased risk factors has stage A heart failure

Question 19

Describe Class IV heart failure (NYHA)

Answer 19

Symptoms with rest

Question 20

What is the main difference in patients with HFpEF and HFrEF?

Answer 20

Anatomical structure of the myocardium and myocytes

Question 21

Describe Stage B heart failure

Answer 21

No symptoms

Has structural heart disease and/or functional heart abnormalities strongly sassociated with heart failure

(ex: Previous MI, Asymptomatic LV systolic dysfunction, LV hypertrophy)

Question 22

This graph represents grade _____ diastolic dysfunction.

How do you know?

What other indications might be present?

Answer 22

This graph represents grade II (moderate) diastolic dysfunction.

• E velocity is normal: E/A >1
  
  • Looks about the same as the normal graph, but this is because increased atrial pressure is present in addition to impaired ventricular relaxation
• Increased LA size and pressure
• Decreased E’ velocity

Question 23

A patient with advanced structural heart disease and markded symptoms of heart failure despite maximum medical therapy has stage ___ heart failure

Answer 23

A patient with advanced structural heart disease and markded symptoms of heart failure despite maximum medical therapy has stage D heart failure

Question 24

Describe the symptoms of right-sided heart failure

Answer 24

• Peripheral edema
• Right upper quadrant discomfort (Due to hepatic enlargement)
• Hepatomegaly
• Jugular venous distension

Question 25

A normal heart meets most of its energy needs by metabolizing \_\_\_\_\_\_\_\_\_\_, but a heart in failure prefers __________ instead

Answer 25

A normal heart meets most of its energy needs by metabolizing **_fatty acids_** , but a heart in failure prefers **_glucose_** instead

Question 26

Heart failure occurs when the heart.... a) \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ b) \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ or both

Answer 26

Heart failure occurs when the heart.... a) Cannot produce enough **cardiac output** to meet metabolic demands b) Can only produce sufficient cardiac output at the expense of **high filling pressures** or **both** a) and b)

Question 27

Describe key features of concentric hypertrophy Cause: Organization of sarcomeres: Effect:

Answer 27

* **Cause** * **​**_Pressure_ overload * **Organization of sarcomeres** * New sarcomeres are created _in parallel_ with existing sarcomeres * Myocyte _thickening_ * **Effect** * Decreased chamber compliance * Increased wall _thickness_ * _​_But cavity size remains the same * Increased ventricular filling pressure * **_Diastolic_ dysfunction**

Question 28

Which extra heart sound is likely present if there is systolic dysfunction?

Answer 28

S3

Question 29

Ejection fraction is a function of \_\_\_\_\_\_\_\_\_, \_\_\_\_\_\_\_\_\_\_\_, and \_\_\_\_\_\_\_\_\_\_\_\_.

Answer 29

Ejection fraction is a function of **_preload,_ _afterload**_ and _**contractility_**.

Question 30

A patient with no symptoms but sructural heart disease and or functional heart abnormalities that are associated with heart failure has **stage \_\_\_** heart failure

Answer 30

A patient with no symptoms but sructural heart disease and or functional heart abnormalities that are associated with heart failure has **stage _B_** ​heart failure

Question 31

\_\_\_\_\_\_\_\_\_ hypertrophy causes dilation of the left ventricle, while ________ hypertropy causes increased LV wall thickness

Answer 31

**_Eccentric_** hypertrophy causes **dilation** of the left ventricle, while **_concentric_** hypertropy causes **increased LV wall thickness**

Question 32

In the setting of heart failure, what causes increased ventricular filling pressures?

Answer 32

**Impaired relaxation (decreased compliance)**, **obstruction to filling**, **fluid overload**, or a combintion of all of the above

Question 33

A patient who gets symptoms with minimal exertion has **class \_\_\_\_** heart failure (NYHA)

Answer 33

A patient who gets symptoms with minimal exertion has **class _III_** heart failure (NYHA)

Question 34

What are the 3 common types of electrical problems seen in heart failure?

Answer 34

* **Atrial fibrilation/Atrial flutter** * Due to atrial fibrosis * **Ventricular tachycardia** * Due to focal reentry around a scar or fibrosis * Seen in systolic HF (HFrEF), especially if the patient has a previous MI * **Interventricular and intraventricular electical dyssynchrony** * Due to ventricle enlargement * Leads to mechanical dyssynchrony

Question 35

A patient with normal ejection fraction but _______ may have reduced cardiac output

Answer 35

A patient with normal ejection fraction but **_a stiff heart_** may have reduced cardiac output (Note: low cardiac output is more often caused by reduced ejection fraction)

Question 36

What are the three phases of diastole?

Answer 36

**Early:** Ventricular relaxation with passive filing fo the ventricle due to pressure gradient **Mid:** Diastasis, when ventricular P = atrial P **Late:** Atrial contraction

Question 37

Describe Stage D heart failure

Answer 37

Advanced structural heart disease Marked symptoms of heart failure despite maximum medical therapy

Question 38

Describe Class II heart failure (NYHA)

Answer 38

Symptoms with major exertion

Question 39

In the setting of heart failure, what causes the heart to generate **insufficient cardiac output?**

Answer 39

**Contractility is impaired**, resulting in **chronic volume overload**. * Impaired contractility may be due to... * Dilated cardiomyopathy * Coronary artery disease (MI, ischemia) * Mitral or aortic regurgitation

Question 40

Describe Stage A heart failure

Answer 40

No symptoms, but has risk factors (like hypertension)

Question 41

What signal in the body triggers the release of natiruetic peptides? In general, what is the effect?

Answer 41

**Hemodynamic stress on the myocardium** * ANP: Atrial * BNP: Ventricles * CNP: Branches of the Aorta Natiruetic peptices counteract the effects of the sympathetic nervous system, RAAS, and AVP (aka ADH)

Question 42

Doppler echocardiography is used to determine diastolic dysfunction presence and severity. What do the E and A waves represent in these graphs?

Answer 42

**E wave:** Early transluminal flow _velocity_ (during ventricular relaxation with passive filling due to pressure gradient) **A wave:** Late transluminal flow _velocity_ (due to atrial contraction) **Not shown: E':** Early myocardial relaxation velocity

Question 43

Describe Class III heart failure (NYHA)

Answer 43

Symptoms with minimal exertion

Question 44

What is the general cause of electrical problems in heart failure?

Answer 44

The normal pattern of conduction is disrupted due to **ventricular and atrial remodeling**

Question 45

A patient presents with dyspnea, and lab tests reveal elevated BNP levels. What does this tell you about the cause of the patient's dyspnea?

Answer 45

**Elevated BNP** increases the likelihood that the dyspnea has a **cardiac cause.** In addition to heart failure, BNP is also elevated in Pulmonary Embolism (Due to RV stress) and Acute Coronary Syndrome (Due to LV stres)

Question 46

This graph represents grade _____ diastolic dysfunction. How do you know? What other indications might be present?

Answer 46

This graph represents **grade** **_III_** **(severe)** diastolic dysfunction. * Increased E velocity (E/A \>1) * Despite impaired relaxation, _due to very high atrial pressures_ * E wave is narrow * Early diastole is very short due to decreased ventricular compliance * Very slow E' * Increased atrial size and pressure

Question 47

What is the most common cause of right heart failure?

Answer 47

Left heart failure

Question 48

Describe Stage C heart failure

Answer 48

Symptomatic heart failure wiht underlying structural heart disease

Question 49

What imaging technique would you use to quantify diastolic dysfunction?

Answer 49

Doppler echocardiography