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Acute heart failure

Summary

Acute heart failure is the rapid onset or worsening of heart failure symptoms, and it is a common cause of hospitalization in older patients. Multiple triggers can cause an acute decompensation of preexisting heart failure (ADHF) but the condition may also occur suddenly in patients with no previous history of the condition (de novo heart failure). Diagnosis is based on typical clinical features (e.g., dyspnea), laboratory findings (e.g., elevated BNP), and imaging findings (e.g., pulmonary edema). Management is often challenging because of comorbidities; most patients require admission for treatment with IV diuretics, vasodilators, adjustment of their chronic heart failure medications, respiratory support, and careful monitoring.

Definition

Etiology

Etiology of acute heart failure
Type of acute heart failure Underlying etiology [1][3]
De novo heart failure
ADHF

Pathophysiology

Clinical features

Clinical features of acute heart failure are commonly classified according to perfusion and the presence of congestion at rest. [1][2][5]

Classification of acute heart failure [5][6]
No evidence of congestion (∼5% of patients) Evidence of congestion (∼95% of patients)
Adequate perfusion
  • Warm and dry
  • Warm and wet
Hypoperfusion
  • Cold and dry
  • Cold and wet

Diagnostics

Diagnosis of acute heart failure consists of a combination of clinical features, laboratory markers (e.g., BNP), and supportive imaging findings. It is important to evaluate for the underlying cause and rule out life-threatening comorbidities (e.g., ACS).

Laboratory studies [7]

  • BNP (or NT-proBNP): Measure in every patient suspected of having acute heart failure.
    • Should always be interpreted in comparison to the patient's baseline and in the context of history, examination, and imaging.
    • High diagnostic utility in patients with unclear diagnosis [7]
    • See “Diagnostics” in “Congestive heart failure.”
  • To evaluate for underlying cause/severity

Measuring BNP (or NT-proBNP) is especially helpful in patients with unclear diagnosis. BNP has a high diagnostic value when combined with physical examination and imaging.

ECG

Indicated in all patients to exclude ACS. Findings are variable and may include: [5][6]

Initial imaging

All patients with suspected acute heart failure should have a CXR and echocardiography performed.

CXR [5][11]

ABCDE: Alveolar edema (bat wings), Kerley B lines (interstitial edema), Cardiomegaly, Dilated prominent pulmonary vessels, and Effusions

Transthoracic echocardiogram (TTE) [5][14]

POCUS in acute heart failure

Advanced imaging

If more detailed information about myocardial viability and/or perfusion is needed (e.g., procedural planning, myocardial ischemia is suspected), further imaging modalities may be necessary after the patient is stabilized. Both MRI and CT require the patient to lie flat for sustained periods and are less accurate at higher heart rates.

Differential diagnoses

See also “Differential diagnoses of dyspnea.”

The differential diagnoses listed here are not exhaustive.

Management

Approach [6]

Hemodynamically unstable patients (i.e., cardiogenic shock)

Management of cardiogenic shock [22][6]
Treatment
Dry and cold
  1. Consider an initial small fluid bolus (250–500 mL) [23][22]
    • Assess fluid responsiveness; consider additional bolus if fluid responsive. [24]
    • Reassess for volume overload
  2. If shock persists, start a vasopressor, ideally, norepinephrine. [22][6][25]
  3. Administer inotropic support if hypoperfusion persists despite fluids and vasopressors [5]
Wet and cold
  1. Administer inotropic support.
  2. If shock persists, start a vasopressor (ideally, norepinephrine ) [22][6][25]
  3. Once systolic BP is > 90 mm Hg, start diuretics (see “Diuretic therapy in acute heart failure”).
  4. If symptoms persist, see the section on “Refractory acute heart failure.”

Avoid inotropes in patients with left ventricular outflow tract obstruction (e.g., hypertrophic cardiomyopathy, aortic stenosis). [26]

Hemodynamically stable patients

Management of hemodynamically stable patients with acute heart failure [6]
Treatment
Dry and warm
  • Optimize oral therapy.
Wet and warm
Wet and cold (if SBP is > 90 mm Hg)

Respiratory support in acute heart failure [6]

EPAP and/or PEEP should be used with caution in patients with hemodynamic compromise.

Diuretic therapy in acute heart failure

  • Initial treatment: Diuretics should administered intravenously (if possible).
    • Diuretic-naive patients: IV furosemide or bumetanide [33]
    • Patients already taking diuretics: Administer 1–2.5 times the patient's usual oral dose intravenously as a bolus or continuous infusion. [23][33]
  • Continuing treatment
  • Monitoring
    • Monitor and replete serum electrolytes (potassium, magnesium, sodium) every 12–24 hours (see “Electrolye repletion”).
    • Monitor urine function (creatinine) at least daily. [5]
    • Consider continuous cardiac monitoring.
  • Transition to oral diuretic: Once the patient is euvolemic/at their baseline. [3]

Vasodilator therapy in acute heart failure [5][6]

Avoid the use of vasodilators in patients with acute heart failure and hypotension.

Treatment of refractory acute heart failure

To remember the management of ADHF, think of “LMNOP”: Loop diuretics (furosemide), Modify medications, Nitrates, Oxygen if hypoxic, Position (with elevated upper body). [23][6]

Ongoing hospital management

Supportive care

Optimization of medical therapy for chronic heart failure [5][2][6]

For patients not previously on beta blockers, use cautiously and only once the patient has been stabilized.

Management of common comorbidities and complications

Monitoring [5][2]

  • Daily weights, intake/output monitoring
  • Renal function, electrolyte monitoring every 12–24 hours (see “Diuretic therapy in acute heart failure”)
  • Consider serial BNP or NT-proBNP measurement. [5][6][44]
  • POCUS can be used to monitor volume overload. [45]

Acute management checklist

All patients

Hemodynamically unstable patients (i.e., cardiogenic shock)

Hemodynamically stable patients

Ongoing management

  • Supportive care: fluid restriction, sodium restriction, VTE prophylaxis, discontinue/avoid any cardiotoxic medications
  • Monitoring: daily weights, strict intake/output, serial electrolytes, renal function
  • Consider continuous telemetry while undergoing diuresis
  • Continuous pulse oximetry if the patient has hypoxia
  • Identify and treat comorbidities/complications (e.g., atrial fibrillation with RVR, hyponatremia).
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last updated 10/12/2020
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