managing-cardiac-risk-preoperative

# Managing Cardiac Risk Preoperative

Applies ACC/AHA perioperative cardiac evaluation algorithm with functional capacity and risk indices.

## Why This Skill Exists

Over 300 million non-cardiac surgeries are performed worldwide annually, and perioperative cardiac complications (MI, heart failure, cardiac death) occur in 1–5% of cases, making it one of the leading causes of postoperative mortality. The 2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management defines a stepwise algorithm for risk assessment, and the 2024 ESC guidelines introduced updated recommendations for biomarker-based risk stratification.

The Revised Cardiac Risk Index (RCRI), functional capacity assessment, and surgical risk classification form the foundation of perioperative cardiac evaluation. Over-testing — ordering stress tests or catheterization in low-risk patients undergoing low-risk surgery — delays surgery without improving outcomes. Under-evaluation — failing to recognize active cardiac conditions in high-risk patients — leads to preventable perioperative events.

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## Checkpoint A: Pre-Draft Intake (Mandatory)

1. What is the planned surgical procedure and its urgency? (default: "Procedure not specified")
2. What is the estimated surgical risk — low (< 1%), elevated (≥ 1%)? (default: "Surgical risk not classified")
3. What is the patient's functional capacity in METs? (default: "Functional capacity not assessed")
4. What are the RCRI risk factors? (default: "RCRI not calculated")
5. Are there any active cardiac conditions (ACS, decompensated HF, significant arrhythmia, severe valve disease)? (default: "Active cardiac conditions not screened")
6. What is the current medication list — beta-blockers, statins, antiplatelets, anticoagulants? (default: "Medications not reviewed")
7. Is there a recent ECG, echocardiogram, or stress test available? (default: "No recent cardiac testing")
8. What is the patient's age and baseline comorbidities (DM, CKD, CVD, HF, CAD)? (default: "Comorbidities not listed")

### Documents to Request

- Surgical procedure description with estimated blood loss and duration
- Recent ECG (within 1–3 months for patients with known cardiac disease)
- Echocardiogram (if HF, valve disease, or new murmur suspected)
- Stress test results (if performed within past 2 years and clinical status unchanged)
- Current medication list
- Labs: BMP, CBC, coagulation studies, BNP/NT-proBNP, troponin (baseline for high-risk)
- Anesthesia assessment
- Prior cardiac history (MI, PCI, CABG, valve surgery, device)
- Functional capacity documentation (interview or formal testing)

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## Step 1: ACC/AHA Stepwise Algorithm

**Step 1: Is the surgery emergent?**
- If YES → proceed to surgery with perioperative risk stratification and surveillance
- If NO → continue algorithm

**Step 2: Are there active cardiac conditions (ACS)?**
Active Cardiac Conditions requiring evaluation/treatment before elective surgery:
- Unstable angina or recent MI (within 60 days)
- Decompensated heart failure
- Significant arrhythmia: high-grade AV block, symptomatic bradycardia, symptomatic VT, SVT with uncontrolled rate, new-onset AF with rapid ventricular response
- Severe aortic stenosis (mean gradient ≥ 40 mmHg, AVA < 1.0 cm²) or symptomatic mitral stenosis

If active cardiac condition present → evaluate and treat before elective surgery.

**Step 3: What is the surgical risk?**

| Risk Category | Estimated MACE Risk | Examples |
|---------------|-------------------|---------|
| Low risk | < 1% | Cataract, endoscopy, superficial procedures, breast surgery |
| Elevated risk | ≥ 1% | Intraperitoneal, intrathoracic, major orthopedic, vascular, head/neck, prostate |

If low-risk surgery → proceed without further cardiac testing.

**Step 4: What is the functional capacity?**

| Functional Capacity | METs | Examples |
|--------------------|------|---------|
| Excellent | ≥ 10 | Running, vigorous sports |
| Good | 7–9 | Singles tennis, heavy housework |
| Moderate | 4–6 | Climbing 2 flights of stairs, walking uphill, heavy housework |
| Poor | < 4 | Difficulty with basic ADLs, walking 1–2 blocks on flat ground |

If functional capacity ≥ 4 METs without symptoms → proceed to surgery without further testing.

**Step 5: If functional capacity < 4 METs or unknown → Calculate RCRI and assess if testing will change management.**

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## Step 2: Revised Cardiac Risk Index (RCRI / Lee Index)

**RCRI Components (1 point each):**

| Factor | Definition |
|--------|-----------|
| High-risk surgery | Intraperitoneal, intrathoracic, or suprainguinal vascular |
| History of ischemic heart disease | Prior MI, positive stress test, current angina, nitrate use, Q waves on ECG |
| History of heart failure | Prior HF, pulmonary edema, S3, bilateral rales, CXR with pulmonary vascular redistribution |
| History of cerebrovascular disease | Prior stroke or TIA |
| Diabetes requiring insulin | Preoperative insulin use |
| Renal insufficiency | Preoperative creatinine > 2.0 mg/dL |

**RCRI Risk Stratification:**

| RCRI Score | Estimated MACE Risk |
|-----------|-------------------|
| 0 | 3.9% (major cardiac events) |
| 1 | 6.0% |
| 2 | 10.1% |
| ≥ 3 | 15% |

*Note: Original Lee data overestimated risk; contemporary estimates are lower, but relative risk stratification remains valid.*

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## Step 3: Preoperative Cardiac Testing Decision

**When Testing Is Appropriate:**
- RCRI ≥ 1 AND poor functional capacity (< 4 METs) AND elevated-risk surgery AND testing result will change management

**When Testing Is NOT Appropriate:**
- Low-risk surgery (regardless of patient risk factors)
- Good functional capacity (≥ 4 METs) without symptoms
- Testing will not change surgical decision (e.g., cancer surgery that will proceed regardless)
- Recent adequate stress test (within 2 years) with stable clinical status

**Preoperative Testing Options:**
- Resting ECG: reasonable for patients with known CAD, arrhythmia, PAD, CVD, structural heart disease, or significant risk factors undergoing elevated-risk surgery
- Echocardiogram: indicated for new dyspnea of unknown origin, suspected HF, or known valve disease not recently evaluated
- Stress testing: pharmacologic stress imaging for elevated-risk patients with poor functional capacity and RCRI ≥ 1–2, only if result will change perioperative management
- Biomarkers: preoperative BNP/NT-proBNP for risk refinement (ESC 2024 recommendation); preoperative troponin baseline for high-risk patients

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## Step 4: Perioperative Medication Management

**Beta-Blockers:**
- Continue in patients already on beta-blockers (Class I — abrupt withdrawal is harmful)
- Do NOT start beta-blockers on the day of surgery (POISE trial: reduced MI but increased stroke and death)
- If initiating preoperatively: start ≥ 7 days before surgery, titrate to HR 60–80
- Reasonable to initiate in patients with RCRI ≥ 3 or known CAD undergoing vascular surgery

**Statins:**
- Continue perioperatively in patients already taking statins (Class I)
- Reasonable to initiate preoperatively for vascular surgery patients

**Antiplatelet/Anticoagulant Management:**

| Scenario | Recommendation |
|----------|---------------|
| Aspirin (primary prevention) | Hold 7–10 days before surgery |
| Aspirin (secondary prevention, non-cardiac surgery) | Continue perioperatively (unless high bleed risk) |
| DAPT post-bare-metal stent | Delay elective surgery ≥ 30 days; continue aspirin |
| DAPT post-DES | Delay elective surgery ≥ 6 months (ideally 12 months if ACS); continue aspirin |
| Warfarin | Hold 5 days pre-op; bridge with LMWH if high thromboembolic risk |
| DOACs | Hold 2–3 days (longer if renal impairment or high bleed risk) |

**ACEi/ARBs:** Controversial; reasonable to hold on morning of surgery to reduce intraoperative hypotension (except in HFrEF where benefit of continuation may outweigh risk).

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## Step 5: Postoperative Cardiac Surveillance

**Postoperative Troponin Monitoring (ESC 2024):**
- Recommended for patients with RCRI ≥ 1 undergoing elevated-risk surgery
- Measure troponin at 24 and 48 hours postoperatively
- Perioperative myocardial injury (PMI): troponin elevation above 99th percentile URL with rise/fall pattern, without non-ischemic etiology
- MINS (Myocardial Injury after Non-cardiac Surgery): PMI judged to be ischemic; independently predicts 30-day mortality

**Management of Postoperative MINS/PMI:**
- Cardiology consultation
- Optimize medical therapy: aspirin, statin, beta-blocker (if tolerated)
- Evaluate for obstructive CAD if high clinical suspicion
- Avoid knee-jerk catheterization — many PMI events are demand ischemia (type 2 MI)

**Postoperative AF (new-onset):**
- Occurs in 10–40% of thoracic/cardiac surgery, 5–10% of major non-cardiac surgery
- Rate control first (beta-blocker or diltiazem); assess for underlying cause (infection, volume shifts, pain)
- Anticoagulation: consider if AF persists > 48 hours; long-term anticoagulation decision based on CHA2DS2-VASc

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## Checkpoint B: Post-Draft Alignment (Mandatory)

1. Was the ACC/AHA stepwise algorithm applied in the correct order?
2. Is the RCRI calculated with all six components documented?
3. Is functional capacity assessed and documented in METs?
4. Is the decision to test or not test justified by the algorithm?
5. Is perioperative medication management complete (beta-blocker, statin, antiplatelet plan)?

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## Quality Audit

- [ ] Surgical procedure and risk category (low vs. elevated) documented
- [ ] Active cardiac conditions screened (ACS, decompensated HF, severe valve disease, arrhythmia)
- [ ] Functional capacity assessed in METs with examples
- [ ] RCRI calculated with all 6 components listed
- [ ] ACC/AHA stepwise algorithm followed sequentially
- [ ] Decision to perform or defer cardiac testing justified
- [ ] If testing performed: results documented and impact on management stated
- [ ] Beta-blocker management plan documented (continue, initiate, or not indicated)
- [ ] Statin continuation addressed
- [ ] Antiplatelet/anticoagulant bridging plan specified
- [ ] DAPT timing relative to stent implantation checked
- [ ] Postoperative troponin surveillance ordered for appropriate patients
- [ ] Anesthesia team communication documented
- [ ] Overall cardiac risk clearance statement provided

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## Guidelines

1. Follow the ACC/AHA stepwise algorithm in ORDER — skipping steps leads to inappropriate testing or missed active conditions.
2. Low-risk surgery (< 1% MACE risk) does not require preoperative cardiac testing regardless of patient comorbidities — proceed to surgery.
3. Do NOT initiate beta-blockers on the day of surgery — the POISE trial demonstrated net harm (increased stroke and all-cause mortality despite reduced MI).
4. Functional capacity ≥ 4 METs without cardiac symptoms is the single most useful piece of information in perioperative risk assessment — if present, further testing is rarely needed.
5. Stent patients on DAPT have the highest perioperative risk — elective surgery should be delayed ≥ 30 days after BMS and ≥ 6 months after DES (12 months after ACS with DES).
6. Preoperative stress testing should only be performed when the result will change management — if surgery will proceed regardless of results, testing adds no value and only delays care.
7. Postoperative troponin monitoring (24h and 48h) is recommended by ESC 2024 for patients with RCRI ≥ 1 undergoing elevated-risk surgery — MINS is an independent mortality predictor.
8. New postoperative AF should be evaluated for underlying triggers (infection, volume overload, PE) rather than treated as an isolated arrhythmia.