What are the anaesthetic considerations for a female patient with severe symptomatic mitral stenosis presenting with dyspnea and a murmur, functional capacity less than four metabolic equivalents, undergoing vaginal hysterectomy?

Anaesthetic Management of Severe Symptomatic Mitral Stenosis for Vaginal Hysterectomy

This patient requires preoperative cardiac intervention before proceeding with vaginal hysterectomy, as she meets criteria for percutaneous mitral commissurotomy (PMC) or surgical correction prior to intermediate-risk noncardiac surgery. 1, 2

Immediate Preoperative Assessment

Determine if surgery can be safely delayed for cardiac intervention:

• Patients with severe mitral stenosis (valve area <1.5 cm²) who are symptomatic with dyspnea and have functional capacity <4 METs are at significantly increased perioperative risk and should undergo PMC before elective intermediate-risk surgery. 1, 2

• Vaginal hysterectomy is classified as intermediate-risk surgery (cardiac risk 1-5%), which warrants careful preoperative cardiac optimization in patients with severe valvular disease. 1

• The combination of symptoms, poor functional capacity (<4 METs), and severe stenosis places this patient at high risk for perioperative heart failure, pulmonary edema, and hemodynamic decompensation. 1

If Surgery Cannot Be Delayed

When cardiac intervention is not feasible and surgery must proceed urgently, the following anaesthetic strategy is critical:

Hemodynamic Goals - The "Slow, Full, and Tight" Approach

Heart Rate Control (Target: 60-80 bpm):

• Maintain strict heart rate control as the single most important hemodynamic goal, because tachycardia shortens diastolic filling time across the fixed stenotic valve, precipitating acute pulmonary edema. 1, 3
• Avoid tachycardia at all costs - even modest increases in heart rate (>90 bpm) can cause catastrophic hemodynamic deterioration. 1
• Beta-blockers should be continued perioperatively and additional beta-blockade administered if heart rate exceeds target. 1, 3

Preload Optimization:

• Maintain adequate preload ("keep them full") as these patients are preload-dependent and cannot increase cardiac output by increasing stroke volume across the fixed stenotic valve. 1
• Avoid hypovolemia, excessive diuresis, or neuraxial techniques that cause significant sympathectomy and venodilation. 1
• Cautious fluid administration is required - these patients are on a narrow therapeutic window between pulmonary edema and inadequate cardiac output. 1

Afterload Management:

• Maintain normal-to-slightly elevated systemic vascular resistance ("keep them tight") to preserve coronary perfusion pressure and prevent cardiovascular collapse. 1, 3
• Avoid vasodilators and drugs that cause significant afterload reduction. 3

Contractility:

• Maintain normal sinus rhythm if present; if atrial fibrillation exists, ensure rate control before induction. 1
• Avoid myocardial depressants. 1

Anaesthetic Technique Selection

Regional anaesthesia is relatively contraindicated in severe symptomatic mitral stenosis:

• Neuraxial techniques (spinal/epidural) cause sympathectomy with venodilation and decreased preload, plus potential for decreased afterload - both poorly tolerated in mitral stenosis. 1
• If regional anaesthesia is absolutely necessary, use incremental epidural dosing with invasive monitoring rather than single-shot spinal. 1

General anaesthesia is preferred:

• Provides better hemodynamic control and ability to manage acute decompensation. 1
• Use etomidate or ketamine for induction (maintain hemodynamic stability). 1
• Avoid propofol (causes vasodilation and myocardial depression). 1
• Maintain anaesthesia with volatile agents at minimal concentrations or opioid-based technique. 1

Monitoring Requirements

Invasive monitoring is strongly recommended:

• Arterial line for beat-to-beat blood pressure monitoring and frequent blood gas analysis. 1
• Central venous pressure monitoring to guide fluid management. 1
• Consider pulmonary artery catheter or transesophageal echocardiography for high-risk cases to directly measure pulmonary artery pressures and guide management. 1
• Continuous ECG monitoring for arrhythmia detection. 1

Intraoperative Management Pitfalls

Critical errors to avoid:

• Never allow tachycardia - this is the most common cause of intraoperative decompensation in mitral stenosis. 1
• Never give excessive fluid boluses - these patients develop pulmonary edema rapidly with volume overload. 1
• Never allow significant hypotension - maintain MAP >65 mmHg to preserve coronary and systemic perfusion. 1, 3
• Avoid drugs that increase heart rate: pancuronium, ketamine (relative), atropine, glycopyrrolate (use cautiously). 1
• Avoid drugs causing significant vasodilation: propofol, volatile agents in high concentrations, neuraxial blockade. 1

Postoperative Considerations

High-dependency or ICU admission is recommended:

• Continue invasive monitoring for 24-48 hours postoperatively. 1
• Maintain strict heart rate control with beta-blockers. 1, 3
• Careful fluid balance monitoring - these patients are at risk for both pulmonary edema and inadequate cardiac output. 1
• Early mobilization increases risk of hemodynamic instability; advance activity cautiously. 1

Anticoagulation Management

If patient has atrial fibrillation (common with mitral stenosis):

• Warfarin should be bridged with unfractionated heparin or low-molecular-weight heparin perioperatively. 1
• Never use DOACs in mitral stenosis patients - they are contraindicated. 1, 3
• Resume therapeutic anticoagulation as soon as surgical hemostasis permits. 1

Optimal Management Pathway

The correct approach is to delay elective surgery and refer for cardiac intervention:

• PMC should be performed before proceeding with vaginal hysterectomy if valve anatomy is favorable (minimal calcification, preserved subvalvular apparatus). 1, 2
• Even with unfavorable anatomy, PMC may be attempted as a bridge to surgery in symptomatic patients when surgical risk is prohibitive. 1, 2
• After successful PMC, patients can safely undergo noncardiac surgery with significantly reduced perioperative risk. 1, 2

This patient's presentation (severe stenosis + symptoms + METs <4) represents a Class I indication for intervention before elective intermediate-risk surgery according to ESC guidelines. 1