PATHOPHYSIOLOGY LEARNING
OBJECTIVES FOR EXAM 3 AUGUSTA
UNIVERSITY
,Heart Failure and Shock
1. Describe the pathophysiology of heart failure and describe whether adaptive mechanisms are
helpful in compensating.
Heart failure is when the heart fails to pump blood forward.
Right-sided heart failure is when the ventricle cannot effectively move blood into the pulmonary
circulation. Blood then backs up in the systemic circulation and causes peripheral edema and
congestion of the abdominal organs.
Left-sided heart failure is when the left ventricle cannot effectively move blood into systemic
circulation. Blood backs up into the pulmonary circulation and causes pulmonary congestion.
Cardiac output is also reduced.
2. Define systolic dysfunction in heart failure related to ejection fraction.
Systolic dysfunction is also known as heart failure with reduced ejection fraction. The left side of
the heart isn’t pumping blood out to the body as well as it normally should (reduction in
pumping power of the left ventricle so ejection fraction is < 40%). . Normal ejection fraction is
55% to 65%, but anything lower or higher could indicate a heart problem. Systolic dysfunction
can be caused by other heart conditions like high blood pressure, coronary artery disease, or a
damaged heart.
3. Know the definitions and causes of orthopnea and PND.
Orthopnea is a sensation of breathlessness when in the recumbent position, but it is relieved by
sitting or standing. It is shortness of breath that occurs when lying flat due to volume overload in
the lungs.
Paroxysmal nocturnal dyspnea (PND) is a sensation of shortness of breath that wakes the patient
and is usually relieved in the upright position. It can also be because of pulmonary volume
overload.
4. Know the causes and the signs / symptoms of right sided heart failure and left sided heart
, failure.
Right Sided Heart Failure
- Distention of jugular veins
- Fluid retention and peripheral edema
- Ascites, anorexia, and malnutrition
Left Sided Heart Failure
- Shortness of breath
- Rales (crackles)
- Cyanosis
- Fatigue and limited exercise tolerance
5. Know the treatment goals in heart failure related to determinants of cardiac outputs.
Improving cardiac output (HR x SV). We want to treat the cause – reduce the workload and
oxygen needs of the myocardium, enhance pumping action, manage alterations in peripheral
vascular resistance, and manage volume.
Treat the reversible causes, medication for symptom relief, medication to block compensatory
mechanisms, medication to increase contractility, low sodium diet / fluid restriction, daily
weights
6. Name a hormone that is released from the LV during acute heart failure.
Brain Natriuretic Peptide (BNP) is the hormone that is released from the ventricular myocardium
when it is failing. It is measured in the serum to help differentiate heart failure from other causes
of SOB (like pulmonary causes).
7. Name a major risk factor for cardiogenic shock.
Cardiogenic shock is the failure of the heart to pump blood adequately (extreme heart – pump –
failure). The most common cause is post-myocardial infarction.
8. Describe the body’s response to hypovolemic shock.
Hypovolemic shock is the loss of whole blood, plasma, and extracellular fluid. The body responds
with decreased intravascular volume, decreased venous return, stroke volume, cardiac output,
tissue perfusion. Heart rate and contractility increase in an attempt to maintain BP.