A 72-year-old woman with a history of myocardial infarction 8 months ago and stable angina on medical therapy presents for elective open abdominal aortic aneurysm (AAA) repair. On pre-operative evaluation, she reports dyspnea on exertion (climbing one flight of stairs), orthopnea, and lower extremity edema. Her ECG shows prior inferior wall MI changes. Echocardiography reveals left ventricular ejection fraction (LVEF) of 35% and moderate mitral regurgitation. BNP is elevated at 450 pg/mL. What is the most appropriate pre-operative cardiac management?

Explanation

## Pre-operative Cardiac Risk in High-Risk Surgery ### Clinical Context: AAA Repair as Highest-Risk Surgery **Key Point:** Open AAA repair is classified as **vascular surgery** — the highest-risk category for non-cardiac surgery, with perioperative cardiac event rates of 5–15% in high-risk patients. This patient has multiple independent predictors of cardiac risk. ### RCRI Score Calculation This patient meets the following RCRI criteria: | Criterion | Present? | Points | |---|---|---| | High-risk surgery (vascular) | Yes | 1 | | History of ischemic heart disease (prior MI) | Yes | 1 | | History of congestive heart failure (LVEF 35%, orthopnea, edema) | Yes | 1 | | History of cerebrovascular disease | Not stated | 0 | | Insulin therapy for diabetes | Not stated | 0 | | Serum creatinine >2 mg/dL | Not stated | 0 | | **Total RCRI Score** | | **3** | **High-Yield:** RCRI ≥3 confers **≥4% risk of major adverse cardiac events (MACE)** perioperatively — this is a **very high-risk patient**. ### Functional Capacity Assessment **Clinical Pearl:** This patient's dyspnea on exertion (climbing one flight of stairs) represents **poor functional capacity** — likely <4 metabolic equivalents (METs). Poor functional capacity is an independent predictor of perioperative cardiac complications and should trigger further investigation. ### Pre-operative Cardiac Workup Strategy ```mermaid flowchart TD A[High-risk patient for high-risk surgery]:::outcome --> B{Functional capacity?}:::decision B -->|Poor ≤4 METs| C[Obtain stress test or coronary angiography]:::action B -->|Good >4 METs| D[Proceed with optimization] C --> E{Positive for ischemia?}:::decision E -->|Yes| F[Consider coronary revascularization before AAA]:::action E -->|No| G[Proceed to surgery with medical optimization]:::action F --> H[Delay AAA if non-emergent; optimize CAD]:::action G --> I[Perioperative beta-blockers, statins, ACE-I]:::action ``` **Key Point:** The presence of **active heart failure symptoms** (orthopnea, edema, elevated BNP) and **poor functional capacity** mandates pre-operative stress testing or coronary angiography to identify reversible ischemia. If significant CAD is found, **coronary revascularization should be considered before AAA repair** (unless the AAA is ruptured/symptomatic, in which case emergency repair takes precedence). ### Recommended Management 1. **Obtain pre-operative stress testing** (dobutamine stress echo or exercise treadmill) or **coronary angiography** to assess for inducible ischemia. 2. **If significant CAD is identified:** Consider percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) before elective AAA repair to reduce perioperative cardiac risk. 3. **If no significant ischemia:** Proceed to surgery with **aggressive perioperative medical optimization:** - Continue beta-blockers (target heart rate 60–80 bpm) - Continue ACE inhibitors / ARBs - Initiate or continue high-intensity statins - Optimize diuretics for volume status - Consider perioperative alpha-2 agonists (e.g., clonidine) or extended-release metoprolol **Warning:** Proceeding directly to surgery without pre-operative assessment in a patient with RCRI ≥3, poor functional capacity, and active heart failure symptoms is high-risk and violates ACC/AHA guidelines. **Mnemonic:** **SCAMP** — Stress test, Coronary angiography, Assess functional capacity, Medical optimization, Perioperative monitoring — the sequence for very-high-risk patients.