High-Output Heart Failure

KEY FEATURES

ESSENTIALS OF DIAGNOSIS

• Symptoms and signs of congestive heart failure

• Echocardiographic or right heart catheterization evidence of high cardiac output and normal systolic function

• Presence of a stimulus for high cardiac demands (eg, obesity, liver disease, severe anemia, thyrotoxicosis, arteriovenous fistula, beriberi, after liver transplantation)

GENERAL CONSIDERATIONS

• High demand for cardiac output may not be adequately met, leading to:

  • – Reduced organ perfusion and compensatory mechanisms, such as salt and water retention

  • – Congestion despite normal or elevated cardiac output

• Left ventricular systolic and diastolic function are usually normal but may be reduced if increased demand is incessant

CLINICAL PRESENTATION

SYMPTOMS AND SIGNS

• Dyspnea, fatigue, edema

PHYSICAL EXAM FINDINGS

• Typical findings of congestive heart failure

• Sinus tachycardia frequent

DIFFERENTIAL DIAGNOSIS

• Diastolic heart failure: normal systolic function, but low cardiac output

• Systolic dysfunction heart failure

• Fluid overload, usually iatrogenic

DIAGNOSTIC EVALUATION

LABORATORY TESTS

• Tests of underlying problem: hemoglobin, thyroid hormones, and liver and renal function tests

ELECTROCARDIOGRAPHY

• Increased voltage may be present

IMAGING STUDIES

• Echocardiography

  • – Mild chamber enlargement

  • – Doppler evidence of high cardiac output

TREATMENT

CARDIOLOGY REFERRAL

• Heart failure

HOSPITALIZATION CRITERIA

• Depends on underlying disease because heart failure is usually mild

MEDICATIONS

• Eliminate the underlying cause

• Give diuretics to relieve congestion

MONITORING

• ECG monitoring in hospital as appropriate

DIET AND ACTIVITY

• Low-sodium diet

• Restricted activities

ONGOING MANAGEMENT

HOSPITAL DISCHARGE CRITERIA

• Resolution of problem

FOLLOW-UP

• Depends on underlying problem

COMPLICATIONS

• Eventual systolic dysfunction

PROGNOSIS

• Excellent with relief of underlying problem

PREVENTION

• Avoid conditions that excessively increase cardiac demand

RESOURCES

PRACTICE GUIDELINES

• Echocardiography: indicated for all new cases of congestive heart failure and identifies this subtype

REFERENCES