Heart Failure – Part I:Pathophysiology

Question 1

Heart failure is the inability of the heart to pump blood forward at a sufficient rate to meet the metabolic demands of the body (forward failure), or the ability to do so only if the cardiac filling pressures are abnormally high (___________).”

Answer 1

backward failure

Question 2

Poor FORWARD blood flow is a key requirement of HF=

Answer 2

LOW FLOW (↓ cardiac output)

Question 3

BACKWARD buildup of pressure is almost always present as well=

Answer 3

CONGESTION (↑ filling pressures)

Typically a response to low flow

Question 4

Key Mediators of Blood Flow

Answer 4

Intropy
preload
aftload
cardiac output (=SV*HR)

Question 5

Ventricular output increases in relation to ______ filling

Answer 5

greater

Question 6

Heart failure is the inability of the heart to pump blood forward at a sufficient rate to meet the metabolic demands of the body (__________), or the ability to do so only if the cardiac filling pressures are abnormally high (backward failure).”

Answer 6

forward failure

Question 7

Left ventricular end-diastolic pressure (LVEDP) v. stroke volume

Answer 7

Frank-Starling curves

Question 8

↑ Preload produces increased _______ (and thus CO)

↑ Inotropy produces increased _____ (and thus CO)

Answer 8

SV

SV

Question 9

Inotropy =

Determinants are…

Answer 9

=contractility

Catecholaminergic / adrenergic stimulation
Calcium

Question 10

Major Divisions of HF

Answer 10

Systolic
Diastolic
Left side
Right side

Question 11

Decreased ejection fraction
“HF with reduced ejection fraction” = HFrEF

“left ventricular systolic dysfunction” = LVSD

Ventricular enlargement
“dilated cardiomyopathy” = DCM

Characteristics of?

Answer 11

Systolic dysfunction

Question 12

Normal ejection fraction
“HF with preserved ejection fraction” = HFpEF

“preserved systolic function” = PSF

Ventricular wall thickening
“left ventricular hypertrophy” = LVH

Characteristics of?

Answer 12

Diastolic Dysfunction

Question 13

Impaired filling

↓lusitropy / decrease in relaxation

Answer 13

Diastolic Dysfunction

Question 14

A problem with squeeze

↓contraction / ↓ inotropy

Answer 14

Systolic dysfunction

Question 15

Systolic dysfunction Characteristics

Answer 15

Decreased ejection fraction
“HF with reduced ejection fraction” = HFrEF

“left ventricular systolic dysfunction” = LVSD

Ventricular enlargement
“dilated cardiomyopathy” = DCM

Question 16

Primary causes of systolic HF

Answer 16

Direct destruction of heart muscle cells- MI
Overstressed heart muscle
Volume overloaded heart muscle

Question 17

Diastolic dysfunction Characteristics

Answer 17

Normal ejection fraction
“HF with preserved ejection fraction” = HFpEF

“preserved systolic function” = PSF

Ventricular wall thickening
“left ventricular hypertrophy” = LVH

Question 18

Primary causes of diastolic HF

Answer 18

High afterload/pressure overload
Myocardial thickening/fibrosis
External Compression

Question 19

Under normal circumstances the right ventricle pumps the same amount of blood as the left ventricle, but does it against much _____ pressures

Answer 19

lower

Question 20

RV work is much less, and thus a normal RV is a ____ structure

Answer 20

thin walled

Question 21

Stresses to the RV can cause it to fail to adequately pump blood through the lungs, which causes (2)

Answer 21

↓ circulating blood flow (forward RV HF)

↑ venous pressures (backward RV HF)

Question 22

Primary causes of right-sided HF

Answer 22

Left Heart failure
Lung Disease
RV volume overload
Damage to RV myocardium

Question 23

muscular tissue of the heart. Other tissues are the endocardium

Answer 23

myocardium

Question 24

Systolic dysfunction is typically accompanied by ______

Answer 24

diastolic dysfunction (and vice versa)

Question 25

_______ failure often causes RV failure (most common)

Answer 25

LV

Question 26

Neurohormal activation
Frank-Starling (increasing preload)
Ventricular hypertrophy and dilation

Answer 26

Compensatory responses of the heart to HF