From the Guidelines
In patients with mitral stenosis and hypotension, the primary goal is to maintain adequate preload, systemic vascular resistance, and heart rate control to avoid hemodynamic deterioration. The management of these patients should focus on careful control of heart rate, fluid status, and blood pressure. According to the 2014 ACC/AHA guideline on perioperative cardiovascular evaluation and management of patients undergoing noncardiac surgery 1, patients with severe mitral stenosis are at increased risk for noncardiac surgery and should be managed similarly to patients with aortic stenosis.
The main goals during the perioperative period are to monitor intravascular volume and to avoid tachycardia and hypotension 1. Beta-blockers such as metoprolol or atenolol should be used to control heart rate, aiming for a target of 60-70 beats per minute, allowing for adequate diastolic filling time across the stenotic valve. Diuretics should be used cautiously, with low doses of furosemide only if there is evidence of fluid overload, as excessive diuresis can worsen hypotension by reducing preload.
Vasopressors like norepinephrine may be necessary in acute settings to maintain blood pressure. Atrial fibrillation should be promptly treated with rate control and anticoagulation. Avoid vasodilators, inotropes that increase heart rate, and excessive fluid restriction. The underlying pathophysiology involves restricted left ventricular filling due to the stenotic mitral valve, creating a fixed cardiac output state where tachycardia reduces diastolic filling time and worsens cardiac output, while bradycardia allows more time for blood to cross the stenotic valve.
Definitive treatment with percutaneous balloon valvuloplasty or surgical valve replacement should be considered for severe cases with persistent symptoms, as recommended by the 2014 ESC/ESA guidelines on non-cardiac surgery 1. Patients with mitral stenosis who meet standard indications for valvular intervention should undergo valvular intervention before elective noncardiac surgery, if possible 1.
Key considerations in the management of patients with mitral stenosis and hypotension include:
- Maintaining adequate preload and systemic vascular resistance
- Controlling heart rate to avoid tachycardia
- Avoiding excessive diuresis and fluid restriction
- Prompt treatment of atrial fibrillation with rate control and anticoagulation
- Consideration of definitive treatment with percutaneous balloon valvuloplasty or surgical valve replacement for severe cases.
From the Research
Mitral Stenosis and Hypotension
- Mitral stenosis is a common disease that causes substantial morbidity worldwide 2.
- The relationship between mitral stenosis and hypotension is not directly addressed in the provided studies, but some studies discuss the effect of changes in flow rate on mitral valve area (MVA) in patients with mitral stenosis.
- A study found that changes in flow rate result in small but clinically insignificant changes in echocardiographic MVA measurement 3.
- Another study found that changes in cardiac output result in predictable changes in pressure half-time, and should be considered when performing serial examinations in patients with mitral stenosis 4.
- A study also found that patients with mitral stenosis who developed dyspnea during dobutamine infusion had significantly increased mean transmitral gradient and pulmonary artery systolic pressure compared to those who remained asymptomatic 5.
- The studies suggest that mitral stenosis can have varying effects on cardiac output and blood pressure, but the direct relationship between mitral stenosis and hypotension is not explicitly stated 2, 3, 5, 4.