In a patient with heart failure and left ventricular ejection fraction <40% who is scheduled for a big‑toe ray amputation, how should I risk‑stratify and manage peri‑operative care?

Risk Stratification and Perioperative Management for HFrEF Patients Undergoing Ray Amputation

Patients with heart failure and LVEF <40% undergoing big-toe ray amputation face substantially elevated perioperative mortality risk (2.35-fold higher 90-day mortality compared to patients without HF), requiring continuation of guideline-directed medical therapy except SGLT2 inhibitors, which must be stopped 3-4 days preoperatively. 1

Quantifying Perioperative Risk

Your patient falls into a high-risk category based on their reduced ejection fraction. The mortality data is sobering and should guide your counseling:

• LVEF <40% carries an adjusted odds ratio of 2.35 for 90-day mortality compared to patients without heart failure 1
• Patients with heart failure have a 3-fold greater risk for perioperative death than those with coronary artery disease alone 1
• The degree of systolic dysfunction matters: LVEF <30% confers the greatest perioperative risk, with strongest association when LVEF falls below 35% 1

Critical distinction: Active heart failure symptoms or signs carry higher risk than compensated HF. Assess for decompensation signs including peripheral edema, jugular venous distention, rales, third heart sound, or pulmonary vascular redistribution on chest x-ray 1

Preoperative Assessment Algorithm

1. Determine Current HF Compensation Status

Examine specifically for:

• Volume status: Jugular venous pressure elevation, pulmonary crackles, peripheral edema, weight gain 2
• Perfusion adequacy: Altered mental status, cold extremities, oliguria 3
• Vital signs: Orthostatic hypotension, tachycardia 2

2. Assess Left Ventricular Function

• Obtain or review echocardiography if not performed within the past year in clinically stable patients 1
• For patients with worsening dyspnea or clinical status change, preoperative LV function evaluation is reasonable 1
• Document specific LVEF value, as risk stratifies by severity (<30% vs 30-40%) 1

3. Laboratory Risk Markers

Obtain:

• BNP or NT-proBNP levels to confirm HF diagnosis and severity 4
• Renal function (creatinine, eGFR) and electrolytes, particularly potassium 1
• Consider lactate if hypoperfusion suspected 3

Perioperative Medication Management

Continue These Medications (Class 2a Recommendation)

In compensated HF, continue guideline-directed medical therapy through the perioperative period to reduce risk of worsening heart failure 1:

• ACE inhibitors or ARBs: Continue unless severe renal impairment or hyperkalemia present 1, 4
• Beta-blockers: Continue in all patients with LVEF <40% 1, 4
• Mineralocorticoid receptor antagonists (MRAs): Continue if LVEF ≤35% and no contraindications 1, 4
• Loop diuretics: Continue at lowest dose maintaining euvolemia 2

Mandatory Medication Holds (Class 1 Recommendation)

SGLT2 inhibitors must be stopped 3-4 days before surgery to reduce perioperative metabolic acidosis risk 1:

• Canagliflozin, dapagliflozin, empagliflozin: Stop ≥3 days preoperatively
• Ertugliflozin: Stop ≥4 days preoperatively

This recommendation is endorsed by the American Diabetes Association and represents the single most important medication adjustment 1

Intraoperative Considerations

Avoid factors that worsen hemodynamics:

• Excessive diuresis causing hypovolemia 1
• Positive inotropic agents (unless cardiogenic shock present) 1
• Tachycardia 1
• Reduced preload states 1

Consider invasive monitoring (arterial line, central venous pressure monitoring) for patients with LVEF <30% or symptomatic HF 1

Postoperative Monitoring Strategy

• Resume GDMT immediately postoperatively unless hemodynamic instability develops 1
• Monitor for signs of decompensation: new dyspnea, volume overload, hypoperfusion 3
• Daily assessment of fluid status, electrolytes, and renal function 3
• Maintain oxygen saturation >90% 3

Common Pitfalls to Avoid

1. Do not routinely hold ACE inhibitors/ARBs or beta-blockers perioperatively in compensated patients—continuation reduces mortality and morbidity despite theoretical hypotension concerns 1, 2

2. Do not forget to stop SGLT2 inhibitors—this is a Class 1 recommendation with specific timing requirements 1

3. Do not assume all HF patients have equal risk—active symptoms versus compensated status dramatically changes outcomes 1

4. Do not delay surgery for asymptomatic LV dysfunction alone if patient is on optimized GDMT—the presence of symptoms matters more than LVEF in isolation 1

Risk Mitigation Summary

The evidence strongly supports that maintaining neurohormonal blockade (ACE inhibitors/ARBs, beta-blockers, MRAs) through the perioperative period provides mortality benefit that outweighs theoretical concerns about hypotension in compensated patients 1, 2. The only exception is SGLT2 inhibitors, which carry specific metabolic acidosis risk requiring preoperative discontinuation 1.

For this specific patient with LVEF <40% undergoing ray amputation, optimize volume status preoperatively, continue all GDMT except SGLT2 inhibitors (stopped 3-4 days prior), and plan for enhanced postoperative monitoring given the 2.35-fold increased 90-day mortality risk 1.