Congestive Heart Failure Flashcards
What is the definition of heart failure?
Inability of heart to pump blood sufficiently to meet metabolic needs of body
OR
ability to do so, but with an abnormally high filling pressure (ventricular pressure)
What happens to stroke volume when you increase preload?
Increases
What happens to stroke volume when you increase contractility?
Increases
What happens to stroke volume when you increase afterload?
Decreases
What are the two causes of an increase in ventricular end-diastolic pressure?
Increase in diastolic volume
Increase in diastolic stiffness
What causes an increase in end-systolic volume?
Increase in afterload
What is the formula for ejection fraction?
(EDV-ESV) / EDV = stoke volume / EDV
What are symptoms of left-sided heart failure?
Dyspnea on exertion (DOE) Shortness of breath (SOB) Orthopnea Paroxysmal nocturnal dyspnea (PND) Fatigue
What are symptoms of right-sided heart failure?
Jugular venous distension
Peripheral edema
Hepatomegaly
What are the major etiologies of heart failure?
Coronary heart disease Hypertension Cardiomyopathy (dilated, hypertrophic, or infiltrative) Valvular heart disease Pericardial disease
What is the common denominator of right sided heart failure?
Increase in right ventricular diastolic pressure –> increase in venous pressure –> peripheral edema and passive liver congestion
What is the common denominator of left sided heart failure?
Increase in left ventricular diastolic pressure –> increase in pulmonary capillary pressure –> transudation of fluid into lungs
What are causes of stiffening of a ventricle (which then causes increase in ventricular end-diastolic pressure)?
Myocyte abnormality (ischemia or hypertrophy)
Fibrosis
Loss of elasticity
Age
What is a normal ejection fraction?
> 0.50
What is a poor ejection fraction?
<0.30
What are the two categories of heart failure based on systolic function?
HFREF (heart failure with reduced ejection fraction)
HRPEF (heart failure with preserved ejection fraction)
Why does abnormal systolic function in HREF lead to increased LV diastolic pressure?
Poor contraction –> heart dilates to maintain SV –> increases end diastolic pressure
Why would patients with preserved systolic function in HRPEF have increased LV diastolic pressure?
Impaired relaxation or decreased compliance (stiff LV) –> increases end diastolic pressure but no effect on systolic function
What are causes of HFREF?
Dilated cardiomyopathy
Myocardial infarction (not enough muscle)
“End stage” hypertension
What are causes of HFPEF?
Left ventricular hypertrophy (hypertension, aortic valve stenosis)
Hypertrophic cardiomyopathy
Restrictive cardiomyopathy
Constrictive pericarditis
What lab tests can be used to determine if heart failure and the etiology?
Chest x-ray
Echocardiogram
Gated blood pool scan or MUGA (multiple gated acquisition scan)
What are 3 different types of cardiomyopathy?
Dilated
Hypertrophic
Infiltrative
What will you see on an echo for dilated cardiomyopahy?
Dilated ventricle, poorly contracting
What will you see on an echo for hypertrophic cardiomyopathy?
Left ventricular hypertrophy, often asymmetric and vigorously contracting
What will you see on an echo for infiltrative cardiopyopathy?
Looks like left ventricular hypertrophy, but is actually just infiltrated by amyloid
What are secondary causes of dilated cardiomyopathies?
Alcohol
Beriberi
Coxsackie, Cocaine
Doxorubicin
Do the following characteristics increase, decrease, or stay normal in dilated cardiomyopathy?
- LV cavity size
- Wall thickness
- LV contractility
LV cavity size - increased
Wall thickness - normal
LV contractility - decreased
Do the following characteristics increase, decrease, or stay normal in hypertrophic cardiomyopathy?
- LV cavity size
- Wall thickness
- LV contractility
LV cavity size - decreased or normal
Wall thickness - increased
LV contractility - increased
Do the following characteristics increase, decrease, or stay normal in infiltrative cardiomyopathy?
- LV cavity size
- Wall thickness
- LV contractility
LV cavity size - normal
Wall thickness - increased
LV contractility - decreased or normal
What is a gated blood pool scan or MUGA (multiple gated acquisition scan)?
Nuclear labling of read blood cells
Examine radioactivity of amount of blood in cavity at any one time
What are the goals of therapy for heart failure?
Treat hemodynamic abnormalities (treat symptoms)
Treat neurohumoral abnormalities (improve long term survival and preventing remodeling)
What are the categories of drugs used to treat heart failure?
Diuretics
Inotropes
Vasodilators (venous and arterial)
Neurohumoral antagonists
What categories of drugs are used to treat hemodynamic abnormalities (symptoms) of heart failure?
Diuretics
Inotropes
Vasodilators
What categories of drugs are used to treat neurohumoral abnormalities (improve long term survival) of heart failure?
ACE-I
ARB
Spironolactone
Beta-blockers
What is the mechanism of action of diuretics?
Decrease sodium and water via kidney –> decreases intravascular volume –> decreases preload –> decreases pulmonary and peripheral congestion (edema) –> decreases symptoms of heart failure
What are side effects of diuretics?
Overdiuresis Electrolyte disturbances (hypokalemia, hypomagnesemia)
What is the mechanism of action of inotropic drugs?
Increase availability of intracellular calcium, increasing the force of ventricular contraction
What are side effects of inotropic drugs?
Cardiac: arrhythmias, AV block
GI: nausea, vomiting
Other: yellow vision, gynecomastia
What is the mechanism of action of venous vasodilators?
Increase venous capacitance –> blood pools in legs –> decreased venous return to heart –> decreased LV preload –> decreases pulmonary and peripheral congestion (edema) –> decreases symptoms of heart failure
What is the mechanism of action of arteriolar vasodilators?
Reduces TPR –> reduces LV afterload
What are side effects of venous vasodilators?
Headache
Hypotension
Tolerance
What are side effects of arteriolar vasodilators?
Hypotension
Lupus-like syndrome
Describe how neurohormonal response can worsen LV function?
Impaired LV function –> neurohumoral imbalance –> increased systemic vascular resistance –> increased afterload –> further impaired LV function
Describe the cycle of ventricular remodeling and heart failure
Reduced cardiac function –> ventricular dilation –> elevated wall stress –> relative myocardial ischemia –> energy depletion –> progressive interstitial fibrosis –> further activation of adrenergic and RAAS –> reduced cardiac function
If patient has low EF and signs and symptomas of fluid retention, what drugs should they be given?
Diuretic
ACE-I
Beta-blocker
If patient has low EF and NO signs and symptoms of fluid retention, what drugs should they be given?
ACE-I
Beta blocker
If patient has normal EF, what drugs should they be given?
Diuretics, but need to treat the underlying causes like hypertension and coronary disease
What lab measurement can indicate heart failure?
BNP
Gets released from ventricle due to stretch of myocytes, so it increases with heart failure
