Can noradrenaline (norepinephrine) be used in a patient with severe mitral regurgitation (MR) and aortic regurgitation (AR) with a low ejection fraction and hypotension?

From the Guidelines

Using noradrenaline in a patient with severe mitral and aortic regurgitation, low ejection fraction, and hypotension (BP 75/40) is appropriate and often necessary. Noradrenaline is generally the preferred vasopressor in this scenario as it increases systemic vascular resistance and blood pressure while having minimal effect on heart rate, as suggested by the subgroup analysis of the SOAP II trial 1. Start with a low dose of 0.01-0.05 mcg/kg/min and titrate carefully to achieve a mean arterial pressure of at least 65 mmHg.

Key Considerations

• Close hemodynamic monitoring is essential, ideally with an arterial line for continuous blood pressure measurement.
• While improving blood pressure is critical for organ perfusion, be aware that increasing afterload with noradrenaline could potentially worsen regurgitant flow across the damaged valves.
• However, the benefit of restoring adequate perfusion pressure usually outweighs this concern in severely hypotensive patients, as emphasized by the importance of managing acute heart failure (AHF) with a focus on early identification of precipitants/causes leading to decompensation 1.

Additional Management

• Concurrent inotropic support with agents like dobutamine may be beneficial if cardiac output remains inadequate despite blood pressure improvement.
• Urgent cardiology consultation and echocardiographic assessment should be obtained to guide further management of the valvular disease.
• It is also important to note that vasodilators, which are commonly used in AHF, should be avoided in patients with systolic blood pressure <90 mm Hg and used with caution in patients with severe mitral or aortic stenosis, as recommended by the ESCG guidelines 1.

From the FDA Drug Label

1 INDICATIONS & USAGE Norepinephrine Bitartrate Injection, USP is indicated to raise blood pressure in adult patients with severe, acute hypotension.

5 WARNINGS AND PRECAUTIONS 5. 1 Tissue Ischemia Administration of Norepinephrine Bitartrate Injection to patients who are hypotensive from hypovolemia can result in severe peripheral and visceral vasoconstriction, decreased renal perfusion and reduced urine output, tissue hypoxia, lactic acidosis, and reduced systemic blood flow despite “normal” blood pressure

The patient has severe hypotension with a blood pressure of 75/40, which is an indication for the use of noradrenaline. However, caution is advised as the patient has severe MR+AR with low ejection fraction, which may increase the risk of tissue ischemia and cardiac arrhythmias.

• The patient's hypovolemia status is unknown, and it is crucial to address hypovolemia prior to initiating noradrenaline therapy 2.
• Continuous cardiac monitoring is recommended due to the risk of cardiac arrhythmias 2. It is essential to weigh the benefits and risks of using noradrenaline in this patient, considering the potential for severe peripheral and visceral vasoconstriction and reduced systemic blood flow. Close monitoring of the patient's condition, including blood pressure, cardiac rhythm, and signs of tissue ischemia, is necessary during noradrenaline therapy 2.

From the Research

Patient Condition

The patient has severe mitral regurgitation (MR) and aortic regurgitation (AR) with a low ejection fraction and currently has a blood pressure of 75/40.

Use of Noradrenaline

• Noradrenaline is a vasopressor that can increase blood pressure, but its use in patients with severe MR and AR is not directly addressed in the provided studies.
• However, the studies suggest that patients with severe MR and AR have a high risk of adverse outcomes, including mortality 3, 4.
• The use of noradrenaline in this patient may be considered to increase blood pressure, but it is essential to weigh the potential benefits against the risks, including the potential to worsen cardiac function.

Aortic Valve Replacement

• Aortic valve replacement (AVR) has been shown to improve survival in patients with severe AR and low ejection fraction 5.
• The studies also suggest that AVR can improve outcomes in patients with severe MR and AR, even in those with low ejection fraction 3, 4.
• However, the decision to perform AVR should be made on a case-by-case basis, taking into account the patient's overall clinical condition and comorbidities.

Clinical Considerations

• The patient's low blood pressure and low ejection fraction suggest that they may be at risk of cardiac decompensation.
• The presence of severe MR and AR adds complexity to the patient's management and may require a multidisciplinary approach, including cardiology and cardiac surgery consultation.
• The use of noradrenaline or other vasopressors should be carefully considered and monitored, with close attention to the patient's hemodynamic and cardiac function 6, 7.