Heart Failure- Lecture

Question 1

Congestive heart failure by definition is _

Answer 1

Congestive heart failure by definition is the inability of the heart to pump blood throughout the body, leading to congestion and decreased perfusion

Question 2

Systolic heart failure means _

Answer 2

Systolic heart failure means loss of contractile strength which results in low ejection fraction
* Failure of the left ventricle

Question 3

Diastolic heart failure is _

Answer 3

Diastolic heart failure is a problem filling the heart; our ejection fraction will often be normal

Question 4

High output heart failure means that _

Answer 4

High output heart failure means that our cardiac output exceeds metabolic demand

Question 5

Uncompensated heart failure is _

Answer 5

Uncompensated heart failure is when symptoms are worsened or exasterbated
* Precipitating factors: infection, arrhythmias, high salt diet, hypertension, MI

Question 6

Systolic heart failure most commonly results from _ or _

Answer 6

Systolic heart failure most commonly results from cardiomyopathy or ischemic heart disease

Question 7

Systolic heart failure –> low ejection fraction –> high EDV –> hypoperfusion to organs including the kidney –> ?

Answer 7

Systolic heart failure –> low ejection fraction –> high EDV –> hypoperfusion to organs including the kidney –> compensatory activation of the sympathetic nervous system and renin release from the juxtaglomerular apparatus
* Increased levels of renin, angiotensin, and aldosterone
* Vasoconstrictive effect of angiotensin II causes increased peripheral resistance
* Mineralocorticoid effects of aldosterone causes fluid retention and metabolic alkalosis

Question 8

Diastolic heart failure is a problem of decreased _ and is most commonly a result of _

Answer 8

Diastolic heart failure is a problem of decreased compliance and is most commonly a result of hypertrophy

Question 9

In diastolic heart failure, ejection fraction will be _ and EDV will be _

Answer 9

In diastolic heart failure, ejection fraction will be normal and EDV will be normal

Question 10

(True/False) Normal BNP excludes congestive heart failure

Answer 10

True; Normal BNP excludes congestive heart failure

Question 11

Name 3 cardinal signs of right heart failure

Answer 11

Right heart failure:
1. Distended jugular veins: due to elevated right atrial pressure
2. Hepatomegaly: due to elevated IVC pressure
3. Peripheral edema: due to elevated capillary bed pressure

Question 12

If a patient has edema but clear lung sounds; they most likely have (left/ right) heart failure

Answer 12

If a patient has edema but clear lung sounds; they most likely have right heart failure

Question 13

Three cardinal signs of left heart failure

Answer 13

Left heart failure:
1. Pulmonary rales (“crackles”): elevated pulmonary capillary pressure (from high LVEDP)
2. S3 or S4: increased LV pressure, decreased compliance
3. Orthopnea: increased venous return

Question 14

Orthopnea is _

Answer 14

Orthopnea is breathlessness when lying flat
* Waking up at night from orthopnea is called paroxysmal nocturnal dyspnea

Question 15

Patients with hypertrophy will have _ ECG findings

Answer 15

Patients with hypertrophy will have big, spikey S waves in V1 and big, spikey R waves in V5 and V6

Question 16

What causes paroxysmal nocturnal dyspnea?

Answer 16

Paroxysmal nocturnal dyspnea occurs when the excess fluid below the waist has a chance to travel back up to the lungs after lying down

Question 17

Describe the pathway of fluid build up in right heart failure

Answer 17

Fluid accumulates in RV –> RA –> IVC and SVC –> Systemic veins –> includes liver

Question 18

Hepatomegaly, ascites, and even cirrhosis of the liver can all result from (left/right) sided heart failure

Answer 18

Hepatomegaly, ascites, and even cirrhosis of the liver can all result from right sided heart failure

Question 19

Another pressure analogous to jugular venous pressure is _

Answer 19

Another pressure analogous to jugular venous pressure is central venous presssure

Question 20

Central venous pressure is _

Answer 20

Central venous pressure is right ventricular preload

Question 21

Normal CVP/ JVP is _

Answer 21

Normal CVP/ JVP is less than or equal to 7 mmHg
* It is either only barely visible above the clavicle or not visible at all

Question 22

Name some things that can lead to heart failure

Answer 22

All of the following can result in heart failure
* Hypertension
* Myocardial infarction
* Dilated cardiomyopathy
* Arrhythmia
* Congenital heart disease
* Valvular disease

Question 23

Draw a pressure volume loop that represents a decrease in contractility

Answer 23

We see a decrease in the End Systolic Pressure Volume Relationship slope
* Decreasing contractility will also decrease stroke volume

Question 24

Explain the change to the variables in LaPlace as we compensate for heart failure

Answer 24

When we are in systolic heart failure, our LVEDV is very large –> this means radius is big in Laplace equation –> Pressure * radius / 2 * wall thickness –> to try to prevnent wall stress from getting to large we will increase the wall thickness

Ultimately we compensate for large LVEDV by increasing wall thickness which is why the heart hypertrophies

Question 25

Heart failure begins with a change in _

Answer 25

Heart failure begins with a change in **contractility** * Contractility decreases --> higher preload is required to increase stroke volume via Frank-Starling Mechanism --> hypertrophy --> remodeling

Question 26

Define pathological and physiological hypertrophy

Answer 26

* **Physiological hypertrophy** involves an addition of myofibrils (sarcomeres) in parallel aka due to development, pregnancy, exercise * **Pathologic hypertrophy** involves an addition of myofibrils (sarcomeres) in parallel aka *concentric hypertrophy* due to pressure loading; **involves fibrosis and sometimes cardiac dysfunction**

Question 27

Explain cardiac dilation in the context of heart failure

Answer 27

Patients with dilated cardiomyopathy or myocardial infarctions will experience **cardiac dilation** aka *addition of myofibrils (sarcomeres) in series which is called eccentric hypertrophy* * Some patients who have concentric hypertrophy can experience remodeling to cardiac dilation * Involves fibrosis, myocyte death, cardiac dysfunction (MI)

Question 28

Explain the role of SNS involvement in heart failure

Answer 28

The body responds to the decreased perfusion in the organs by increasing SNS --> this acts on B1 receptors to increase **heart rate (chronotropy) and contractility (inotropy)** --> NE also acts on receptors in the kidney to increase renin release and promote fluid retention * Note that NE also activates venous alpha1 receptors to vasoconstrict --> decrease venous compliance and increase venous return

Question 29

Acutely, SNS compensation is adaptive and can improve cardiac output in a heart that has impaired contractility; what is the problem long term?

Answer 29

The heart is not designed to withstand this kind of SNS activation long term * Chronic beta stimulation will lead to eventual **downregulation of B1 receptors** * We also end up putting too much oxygen demand --> myocardial injury * We end up with energy starvation, cardiomyocyte death, ventricular arrhythmias, fibrosis *Ultimately NE and E are great for acute responses but are toxic with sustained exposure*

Question 30

What is the problem with activating RAAS in heart failure?

Answer 30

We are increasing RAAS with the hopes of helping our cardiac ouput; however, our contractility is still crap and we are still not perfusing well * Decreased CO decreases renal perfusion which turns on RAAS --> cycle just continues --> negative feedback is disrupted

Question 31

After myocardial insult we get cardiac remodeling with involves _

Answer 31

After myocardial insult we get cardiac remodeling with involves: * Big cardiomyocytes * Cardiomyocytes that have less myofibrils, abnormal Ca2+ * Apoptosis and necrosis * Fibrosis * Poor heart function * Heart failure --> death

Question 32

Question 33

When we triage heart failure we want to know _ and _ to determine how to treat (outpatient, inpatient, ICU)?

Answer 33

When we triage heart failure we want to know **cardiac ouput** and **pulmonary capillary wedge pressure (volume status)** to determine how to treat (outpatient, inpatient, ICU)? * Poor cardiac output = cold patient = ICU * Warm and dry patient = outpatient * Warm and wet patient = inpatient diuretics needed

Question 34

Diuretics can have beneficial hemodynamic effects through _ which helps alleviate the symptoms of HF without decreasing _

Answer 34

Diuretics can have beneficial hemodynamic effects through **decreasing preload (LVEDV)** which helps alleviate the symptoms of HF without decreasing **stroke volume**

Question 35

Which heart failure therapies reduce mortality?

Answer 35

Reduce mortality: * ACE inhibitors * ARBs * ARNIs * Aldosterone inhibitors * Beta blockers * Sglt2 inhibitors

Question 36

Beta blockers should be used in (acute/ chronic) heart failure

Answer 36

Beta blockers should be used in **chronic** heart failure * They should be avoided in acute decompensated heart failure!

Question 37

Adverse effects of beta blockers include _

Answer 37

Adverse effects of beta blockers include **bradycardia, heart block, bronchospasm, depression, sexual dysfunction** * Can block the signs of hypoglycemia in diabetics by blocking the reflex tachycardia

Question 38

Sglt2 inhibitors decrease preload and afterload by _

Answer 38

Sglt2 inhibitors decrease preload and afterload by **natriuresis** * Traditionally used for diabetic patients to block the reabsorption of glucose --> water follows glucose --> therefore blocks the reabsorption of water * **Dapagliflozin** and **empagliflozin**

Question 39

Digoxin is an old school medication that was often used with the intension of _ ; it works via _ mechanism

Answer 39

**Digoxin** is an old school medication that was often used with the intension of **increasing contractility** ; it works via **Na/K ATPase inhibition** --> this blocks the ability of Na/Ca2 antiporter to extrude calcium

Question 40

The reason that digoxin is largely avoided today is because of its _

Answer 40

The reason that digoxin is largely avoided today is because of its **narrow therapeutic window**

Question 41

Normal ejection fraction should be greater than _ ; below _ is diagnostic of heart failure; below _ we should consider an implantable defibrillator

Answer 41

Normal ejection fraction should be greater than **55%** ; below **40%** is diagnostic of heart failure; below **35%** we should consider an implantable defibrillator