Cardiac Risk in Non-cardiac Surgery

Cardiac Risk in Non-cardiac Surgery - Pre-Op Heart Check

• Goal: Identify patients at ↑ risk of Major Adverse Cardiac Events (MACE).
• Initial Assessment:
  • History (angina, dyspnea), physical exam.
  • Functional capacity: Metabolic Equivalents (METs). <4 METs = poor (e.g., can't climb 1 flight of stairs).
• Risk Stratification Tools:
  • Revised Cardiac Risk Index (RCRI): 6 factors (1 pt each).
    • High-risk surgery, Ischemic Heart Disease (IHD), Congestive Heart Failure (CHF), Cerebrovascular Disease (CVA), Insulin Rx Diabetes Mellitus, Serum Creatinine >2 mg/dL.
    • Scores & MACE risk: 0 pts (0.4%), 1 pt (0.9%), 2 pts (6.6%), ≥3 pts (11%).
  • NSQIP MICA / Gupta Perioperative Cardiac Risk Calculator.

⭐ Patients unable to perform 4 METs of activity (e.g., climb two flights of stairs or walk briskly on a level surface) have significantly increased perioperative cardiac risk and may warrant further cardiac evaluation if undergoing high-risk surgery.

Cardiac Risk in Non-cardiac Surgery - Spotting Red Flags

• Key Risk Factors (RCRI components):
  • High-risk surgery (e.g., vascular, intrathoracic)
  • History of Ischemic Heart Disease (IHD)
  • History of Congestive Heart Failure (CHF)
  • History of Cerebrovascular Disease (CVA/TIA)
  • Insulin therapy for Diabetes
  • Pre-op serum creatinine > 2.0 mg/dL
• Functional Capacity (METs):
  • Poor: < 4 METs (e.g., cannot climb 1 flight of stairs) ⚠️ High risk indicator!
  • Moderate: 4-10 METs (e.g., light housework)
  • Excellent: > 10 METs (e.g., strenuous sports)
• Urgent "Red Flags" (Postpone/Optimize):
  • Recent MI (< 30-60 days)
  • Unstable or severe angina
  • Decompensated Heart Failure
  • Significant arrhythmias (e.g., high-grade AV block, symptomatic ventricular arrhythmias)
  • Severe valvular disease (e.g., symptomatic aortic stenosis; AS: mean gradient > 40 mmHg, valve area < 1.0 $cm^2$)

⭐ For patients with an RCRI score of 0, MACE risk is ~0.4-0.5%; score 1 ~0.9-1.3%; score 2 ~4-6.6%; score ≥3 ~9-11%.

Cardiac Risk in Non-cardiac Surgery - Tailoring The Plan

• Ischemic Heart Disease (IHD):
  • Beta-blockers: Continue.
  • Aspirin: Continue if stented/high-risk surgery. Stop 5-7 days if primary prevention.
  • DAPT: BMS >30 days, DES >6 months (ideally 12 months) post-PCI. Urgent: continue DAPT/aspirin.
• Valvular Heart Disease (VHD):
  • Severe symptomatic AS (gradient >40 mmHg, AVA <1.0 cm²), Severe MS (MVA <1.5 cm²): High risk. Consider pre-op valve intervention.
  • Prosthetic valves: Bridge anticoagulation (LMWH/UFH).
• Heart Failure (HF):
  • Optimize medical therapy. Delay if acutely decompensated (NYHA Class IV).
  • LVEF <30% indicates high risk.
• Arrhythmias:
  • Atrial Fibrillation (AF): Ensure rate control. Anticoagulation: continue or bridge.
  • Ventricular arrhythmias: Investigate cause, optimize treatment.

⭐ Beta-blockers should be continued if already prescribed; avoid acute pre-operative initiation unless specific indications (e.g., thyrotoxicosis, active ischemia).

Cardiac Risk in Non-cardiac Surgery - Shielding The Heart

• Risk Stratification: RCRI/NSQIP. Functional capacity <4 METs = high risk.
• Pharmacotherapy:
  • Beta-blockers: Continue. Start if ≥3 RCRI/CAD; target HR 55-70 bpm.
  • Statins: Continue. Consider for vascular surgery.
  • Aspirin: Continue if high-risk (stent); stop 7 days if low-risk.
  • DAPT: Defer surgery post-stent (BMS: 4-6 wks, DES: 6-12 mths).
  • Warfarin: Stop 5 days pre-op (INR <1.5); bridge.
  • DOACs: Stop 2-5 days pre-op (drug/renal dependent).
• Perioperative Care:
  • ECG, BP monitoring (invasive if high-risk).
  • Post-op troponin for high-risk.

⭐ Initiate beta-blockers >1 day (ideally 1 week) pre-op if indicated, not on surgery day.

High‑Yield Points - ⚡ Biggest Takeaways

• RCRI (Revised Cardiac Risk Index) is key for preoperative cardiac risk assessment; 6 predictors identify high-risk patients.
• Functional capacity assessed by METs; <4 METs indicates poor capacity and ↑ MACE risk.
• Continue beta-blockers and statins if patient is already taking them; avoid abrupt withdrawal.
• Aspirin management balances thrombotic vs. bleeding risk; often continued in high cardiac risk.
• Delay elective surgery post-PCI with DES until DAPT (Dual Antiplatelet Therapy) completion.
• Elevated BNP/NT-proBNP levels preoperatively signify ↑ perioperative cardiac risk.
• Primary goal is to prevent MACE (Major Adverse Cardiac Events) like MI or cardiac death_