What is the management of acute aortic regurgitation (AR)?

Management of Acute Aortic Regurgitation

In acute aortic regurgitation (AR), immediate surgical intervention is the definitive treatment and should not be delayed, especially if there is hypotension, pulmonary edema, or evidence of low cardiac output. 1

Diagnosis

Rapid diagnosis is critical in acute AR as it can quickly lead to hemodynamic collapse:

• Transthoracic echocardiography (TTE) or transesophageal echocardiography (TEE) is indispensable for:

  • Confirming presence and severity of AR
  • Determining etiology (endocarditis, aortic dissection, trauma)
  • Evaluating LV size and function
  • Assessing feasibility of valve repair 1

• Key diagnostic findings on echocardiography:

  • Short deceleration time on aortic flow velocity curve (<300 ms)
  • Early closure of mitral valve
  • Holodiastolic flow reversal in aortic arch 1

• For suspected aortic dissection:

  • CT imaging is the primary approach (highly accurate and widely available)
  • TEE has 98-100% sensitivity when CT is unavailable 1

Initial Medical Management

While preparing for surgery, temporary stabilization may be achieved with:

• Vasodilator therapy (preferably nitroprusside) to reduce LV afterload 1, 2
• Inotropic agents (dopamine or dobutamine) may be used to:
  • Augment forward flow
  • Reduce LV end-diastolic pressure 1

Important Cautions

• Intra-aortic balloon counterpulsation is absolutely contraindicated in acute AR 1
• Beta-blockers should be used very cautiously, if at all, except in aortic dissection, as they block compensatory tachycardia 1

Surgical Management

• Urgent surgical intervention is the definitive treatment for acute severe AR 1, 2
• Surgery should not be delayed for medical optimization in most cases
• In cases of infective endocarditis with acute severe AR:
  • Surgery should proceed without delay if hemodynamic compromise is present
  • For mild AR with hemodynamic stability, antibiotic treatment may be sufficient 1

Etiology-Specific Considerations

1. Aortic Dissection:

   • Surgical emergency requiring immediate intervention
   • Beta-blockers may be used cautiously in this specific scenario 1

2. Infective Endocarditis:

   • Urgent surgery if hemodynamically unstable
   • Appropriate antibiotics should be started immediately 1

3. Iatrogenic/Traumatic AR:

   • Requires immediate evaluation and likely surgical intervention 1

Outcomes

Without prompt surgical intervention, acute severe AR commonly leads to:

• Pulmonary edema
• Ventricular arrhythmias
• Electromechanical dissociation
• Circulatory collapse
• Death 1

The key to improving outcomes is rapid diagnosis, temporary medical stabilization when needed, and prompt surgical intervention before irreversible hemodynamic deterioration occurs.