Heart Failure

Question 1

What is it heart failure

Answer 1

. Heart ailure is present when the heart
is unable to pump blood orward at a su f cient rate to meet the metabolic demands o the body or is able to do so only in cardiac filling pressures are abnormally high.

Question 2

This concept o a terload is also relevant to the intact heart:

Answer 2

the pressure generated by
the ventricle and the size o the chamber at the end o each contraction depend on the load
against which the ventricle contracts but are independent o the stretch on the myocardial
f bers be ore contraction

Question 3

In a healthy person, cardiac output is matched to

Answer 3

the body’s total metabolic need.
Cardiac output (CO) is equal to the product o stroke volume (SV, the volume o blood ejected with
each contraction) and the heart rate (HR):
CO = SV x HR

Question 4

The three major determinants o stroke volume are

Answer 4

preload, a terload, and myocardial

contractility,

Question 5

ventricular unction curve

Frank–Starling curve,

Answer 5

the more a normal ventricle is distended (i.e., f lled with blood) during diastole, the greater the volume that is ejected during the next systolic contraction.

Question 6

Preload

Answer 6

the amount of myocardial stretch at the end of diastole, just before contraction

The ventricular wall tension at the end o diastole. In clinical terms, it is the stretch on the ventricular bers just be ore contraction, often approximated by the end-diastolic volume or end-diastolic pressure.

Question 7

Measurements that correlate with myocardial stretch, and that are often
used to indicate the preload on the horizontal axis, are the

Answer 7

Are the ventricular end diastolic volume (EDV) or

or end-diastolic pressure (EDP)

Question 8

Conditions that decrease intravascular volume,

and thereby reduce ventricular preload (e.g., dehydration or severe hemorrhage) result in a smaller

Answer 8

EDV and hence a reduced stroke volume during contraction

Question 9

an increased volume within the le t ventricle during diastole (e.g., a large intravenous uid
in usion) results in a

Answer 9

greater-than-normal stroke volume.

Question 10

Afterload

Answer 10

The ventricular wall tension during contraction; the orce that must be overcome or the ventricle to eject its contents. Often approximated by
the systolic ventricular (or arterial) pressure

Question 11

Contractility (inotropic state)

Answer 11

Property o heart muscle that accounts or changes in the strength of contraction, independent o the preload and a terload. Reflects chemical or hormonal inf uences (e.g., catecholamines) on the orce of
contraction

Question 12

Stroke volume (SV)

Answer 12

Volume o blood ejected rom the ventricle during systole SV = End-diastolic volume – end-systolic volume

Question 13

Ejection raction (EF)

Answer 13

The raction o end-diastolic volume ejected rom the ventricle during
each systolic contraction (normal range = 55%–75%)
EF = Stroke volume ÷ end-diastolic volume

Question 14

Cardiac output (CO)

Answer 14

Volume o blood ejected rom the ventricle per minute

CO = SV × Heart rate

Question 15

Compliance

Answer 15

Intrinsic property o a chamber that describes its pressure–volume
relationship during illing. Re lects the ease or di iculty with
which the chamber can be illed. Compliance = ∆ volume ÷ ∆ pressure

Question 16

isovolumetric contraction

Answer 16

When the pressure in the left ventricle (LV) exceeds that o the left atrium (point b), the
mitral valve is forced to close. As the pressure continues to increase, the ventricular volume
does not immediately change, because the aortic valve has not yet opened; therefore, this
phase is called

Question 17

isovolumetric relaxation

Answer 17

As the ventricle continues to relax, its pressure declines while its volume remains constant
because the mitral valve has not yet opened

Question 18

Ventricular stroke volume is a function of

Answer 18

preload, a terload, and contractility. SV rises

when there is an increase in preload, a decrease in a terload, or augmented contractility

Question 19

Ventricular EDV (or EDP) is used as a representation of preload

Answer 19

he EDV is in uenced by the chamber’s compliance.

Question 20

Ventricular ESV depends on the

Answer 20

afterload and contractility but not on the preload

Question 21

etiologies of Heart failure

Answer 21

1) impair ventricular contractility,
(2) increase a terload,
or (3) impair ventricular relaxation and filling

Question 22

systolic dysfunction

Answer 22

Heart ailure that results rom

an abnormality o ventricular emptying (due to impaired contractility or greatly excessive afterload)

Question 23

diastolic dysfunction

Answer 23

is termed systolic dysfunction, whereas heart ailure caused by abnormalities of diastolic relaxation or ventricular filling is called

Question 24

Impaired Contractility

Answer 24

1. Coronary artery disease
• Myocardial infarction
• Transient myocardial
ischemia
2. Chronic volume overload
• Mitral regurgitation
• Aortic regurgitation
3. Dilated cardiomyopathies 

Leading to

Reduced Ejection Fraction
(Systolic Dysfunction)
Heart Failure

Question 25

Impaired Diastolic Filling

Answer 25

1. Left ventricular hypertrophy
2. Restrictive cardiomyopathy
3. Myocardial fibrosis
4. Transient myocardial ischemia
5. Pericardial constriction or
   tamponade

Leading to

Preserved ejection fraction
(Diastolic Dysfunction)
Heart Failure

Question 26

⇈Afterload

Chronic Pressure Overloada

Answer 26

1. Advanced aortic stenosis
2. Uncontrolled severe hypertension

Leading to

Reduced Ejection Fraction
(Systolic Dysfunction)
Heart Failure

Question 27

Heart Failure with reduced ejection fraction

Answer 27

In states of systolic dysfunction, the affected ventricle has a diminished capacity to eject
blood because of impaired myocardial contractility or pressure overload (i.e., excessive afterload). Loss ofcontractility may result from destruction of myocytes, abnormal myocyte function, or fibrosis. Pressure overload impairs ventricular ejection by significantly increasing resistance to flow

Question 28

Heart Failure with Preserved EF

Answer 28

frequently demonstrate abnormalities of
ventricular diastolic function: impaired early diastolic relaxation (an active, energy-dependent
process), increased sti ness o the ventricular wall (a passive property), or both.
Acute myocardial ischemia is an example of a condition that transiently inhibits energy delivery and
diastolic relaxation.
Conversely, left ventricular hypertrophy, fibrosis, or restrictive cardiomyopathy causes the LV walls to become chronically stiffened.
Certain pericardial
diseases (cardiac tamponade and pericardial constriction, ) present an external force that limits ventricular filling and represent potentially reversible forms of diastolic dysfunction. The effect of impaired diastolic function is reflected in the pressure–volume
loop : in diastole, filling of the ventricle occurs at higher-than-normal pressures because the lower part o the loop is shifted upward as a result of reduced chamber compliance.
Patients with diastolic dysfunction often manifest signs of vascular congestion because the elevated diastolic pressure is transmitted retrograde to the pulmonary and systemic veins

Question 29

Examples of Conditions That Cause Right-Sided Heart Failure

Answer 29

Cardiac causes
Left-sided heart failure
Pulmonic valve stenosis
Right ventricular infarction

Pulmonary parenchymal diseases
Chronic obstructive pulmonary disease
Interstitial lung disease (e.g., sarcoidosis)
Chronic lung infection or bronchiectasis

Pulmonary vascular diseases
Pulmonary embolism
Pulmonary arteriolar hypertension

Question 30

Common Symptoms and Physical Findings in Heart Failure
Symptoms + Physical findings
Left sided

Answer 30

Left sided
 Dyspnea Diaphoresis (sweating)
 Orthopnea Tachycardia, tachypnea
 Paroxysmal nocturnal dyspnea 
Pulmonary rales
 Fatigue Loud P2
S3 gallop (in systolic dysfunction)
S4 gallop (in diastolic dysfunction)

Question 31

Common Symptoms and Physical Findings in Heart Failure

Physical findings + Symptoms

Answer 31

Right sided
 Peripheral edema Jugular venous distention
 Right upper quadrant discomfort
 (because of hepatic enlargement)
Hepatomegaly
Peripheral edema