- Heart failure is the inability of the heart to maintain adequate cardiac output to meet the metabolic needs of the body because of impaired pumping ability.
- Diminished cardiac output results in inadequate peripheral tissue perfusion.
- Congestion of the lungs and periphery may occur; the client can develop acute pulmonary edema.
- Acute heart failure occurs suddenly.
- Chronic heart failure develops over time; however, a client with chronic heart failure can develop an acute episode.
Types of heart failure
- Right ventricular failure, left ventricular failure
- Because the two ventricles of the heart represent two separate pumping systems, it is possible for one to fail alone for a short period.
- Most heart failure begins with left ventricular failure and progresses to failure of both ventricles.
- Acute pulmonary edema, a medical emergency, results from left ventricular failure.
- If pulmonary edema is not treated, death will occur from suffocation because the client literally drowns in his or her own fluids.
- Forward failure, backward failure
- In forward failure, an inadequate output of the affected ventricle causes decreased perfusion to vital organs.
- In backward failure, blood backs up behind the affected ventricle, causing increased pressure in the atrium behind the affected ventricle.
- Low output, high output
- In low-output failure, not enough cardiac output is available to meet the demands of the body.
- High-output failure occurs when a condition causes the heart to work harder to meet the
- demands of the body.
- Systolic failure, diastolic failure
- Systolic failure leads to problems with contraction and ejection of blood.
- Diastolic failure leads to problems with the heart relaxing and filling with blood.
- Compensatory mechanisms act to restore cardiac output to near-normal levels.
- Initially, these mechanisms increase cardiac output; however, they eventually have a damaging effect on pump action.