What is the recommended cardiac workup for a patient with known or suspected cardiovascular disease, hypertension, diabetes, or hyperlipidemia prior to surgery?

Preoperative Cardiac Workup for Patients with Cardiovascular Risk Factors

For patients with known or suspected cardiovascular disease, hypertension, diabetes, or hyperlipidemia undergoing noncardiac surgery, obtain a preoperative 12-lead ECG and proceed with a risk-stratified approach based on functional capacity and surgery type, reserving additional cardiac testing only for patients with poor functional capacity (<4 METs) undergoing intermediate- or high-risk surgery when results would change management. 1, 2

Step 1: Determine Urgency and Surgery Risk Category

• Emergency surgery: Proceed immediately to surgery with perioperative medical management and surveillance; defer comprehensive cardiac evaluation until postoperatively 1
• Elective surgery with active cardiac conditions: Postpone surgery and treat the following conditions first: unstable angina, decompensated heart failure, significant arrhythmias (high-grade AV block, symptomatic ventricular arrhythmias, supraventricular arrhythmias with uncontrolled ventricular rate), or severe valvular disease 1, 2

Surgery risk stratification 1:

• High-risk (>5% cardiac event rate): Vascular surgery, major emergency procedures
• Intermediate-risk (1-5% cardiac event rate): Intraperitoneal, intrathoracic, orthopedic, prostate surgery, hernia repair
• Low-risk (<1% cardiac event rate): Cataract surgery, breast surgery, superficial procedures

Step 2: Obtain Preoperative 12-Lead ECG

Class I indications (must obtain ECG) 1, 2, 3:

• All patients with known cardiovascular disease (coronary artery disease, heart failure, valvular disease, arrhythmias) undergoing intermediate- or high-risk surgery
• All patients with peripheral arterial disease or cerebrovascular disease undergoing intermediate- or high-risk surgery
• Patients with recent chest pain or ischemic equivalent undergoing intermediate- or high-risk surgery
• All patients age ≥65 years undergoing intermediate- or high-risk surgery

Class IIa indications (reasonable to obtain ECG) 1, 2:

• Patients with at least one clinical risk factor (ischemic heart disease, compensated or prior heart failure, diabetes mellitus, renal insufficiency, cerebrovascular disease, hypertension) undergoing intermediate-risk surgery
• Asymptomatic patients with diabetes mellitus undergoing any surgery
• All patients undergoing vascular surgery, even without clinical risk factors

Class III (do not obtain ECG) 1, 2:

• Asymptomatic patients without cardiovascular risk factors undergoing low-risk surgery

Step 3: Assess Functional Capacity

Functional capacity determines need for further testing 1, 2:

• Excellent capacity (≥10 METs): Can climb 2+ flights of stairs or run a short distance without symptoms—proceed directly to surgery regardless of ECG findings 1, 2
• Moderate capacity (4-10 METs): Can do heavy housework, walk up a hill, or walk on level ground at 4 mph—generally proceed to surgery with heart rate control 1
• Poor capacity (<4 METs): Cannot climb 2 flights of stairs or walk 4 blocks—requires further risk stratification 1, 4

Step 4: Apply Clinical Risk Stratification (Revised Cardiac Risk Index)

Count the number of clinical risk factors 1, 5, 4:

1. High-risk surgery (vascular procedures)
2. Ischemic heart disease
3. Congestive heart failure
4. Cerebrovascular disease
5. Insulin-dependent diabetes mellitus
6. Renal insufficiency (creatinine >2 mg/dL)

Risk-based management 1, 2:

• 0 risk factors: Proceed to surgery; no further testing needed
• 1-2 risk factors + moderate/excellent functional capacity: Proceed to surgery with heart rate control (consider beta-blocker)
• 1-2 risk factors + poor/unknown functional capacity: Proceed to surgery with heart rate control; noninvasive testing may be considered if it would change management
• ≥3 risk factors + poor/unknown functional capacity: Consider noninvasive stress testing if results would change management (delay surgery 30 days to optimize medical therapy if high-risk findings)

Step 5: Selective Use of Noninvasive Stress Testing

Indications for stress testing 1, 2, 4:

• Patients with poor functional capacity (<4 METs) and ≥3 clinical risk factors undergoing vascular surgery, only if results would change management (e.g., patient is candidate for coronary revascularization or would benefit from extended medical optimization)
• Patients with unstable angina or active arrhythmia requiring evaluation before surgery

Do NOT perform routine stress testing 1, 5, 4:

• Stress testing does not predict which patients will have perioperative MI or death with sufficient accuracy to justify routine use 5, 4
• Stress testing in patients with 0-2 risk factors delays surgery by up to 3 weeks without improving outcomes 5
• Routine coronary revascularization based on stress test results does not reduce perioperative MI or death rates 5, 4

Choice of stress test 1:

• Exercise ECG: First choice for ambulatory patients with normal baseline ECG
• Pharmacological stress imaging (dobutamine echocardiography or pharmacological myocardial perfusion imaging): For patients with abnormal baseline ECG (left bundle branch block, LV hypertrophy with strain, digitalis effect) or unable to exercise

Step 6: Echocardiography Indications

Class I (must obtain echocardiography) 1:

• Current or poorly controlled heart failure
• Symptomatic patients with suspected severe valvular disease (stenotic lesions require percutaneous valvotomy or valve replacement before noncardiac surgery)

Class IIa (reasonable to obtain) 1:

• Prior heart failure with no recent evaluation
• Dyspnea of unknown origin

Class III (do not obtain routinely) 1:

• Routine assessment in asymptomatic patients without prior heart failure
• Patients with hypertension or diabetes and normal ECG (Class IIb at best)

Step 7: Coronary Angiography Indications

Perform coronary angiography only for established indications independent of planned surgery 1, 4:

• Evidence for high risk of adverse outcome based on noninvasive test results
• Angina unresponsive to adequate medical therapy
• Unstable angina or acute coronary syndrome

Do NOT perform prophylactic coronary revascularization 5, 4, 6:

• Coronary revascularization specifically to reduce perioperative risk does not decrease MI or death rates at 1 month or 6 years 5
• Coronary stenting requires dual antiplatelet therapy, which increases surgical bleeding risk 4, 7

Special consideration for vascular surgery patients 1, 6:

• Coronary angiography is reasonable before surgery in patients with defined CAD risk factors (postmenopausal women, hypertension, smoking, hyperlipidemia) undergoing vascular procedures 1
• 64-slice or higher coronary CT angiography can exclude significant CAD when pretest probability is low to intermediate 1

Step 8: Perioperative Medical Optimization

Hypertension management 1:

• Stage 3 hypertension (≥180/110 mm Hg) must be controlled before elective surgery 1
• Continue all preoperative antihypertensive medications through the perioperative period 1
• Beta-blockers are particularly attractive agents for rapid control 1

Beta-blocker therapy 1, 5, 4:

• Consider starting in patients with ≥1 clinical risk factor: Begin low-dose beta-blocker (bisoprolol 2.5-5 mg/day) 1 month before surgery, titrated to heart rate <70 bpm and systolic BP ≥120 mm Hg 5
• Continue in patients already taking beta-blockers 1
• Do NOT start high-dose beta-blockers 2-4 hours before surgery—this increases stroke (1.0% vs 0.5%, p=0.005) and mortality (3.1% vs 2.3%, p=0.03) 4

Statin therapy 1, 5, 4:

• Start statins ideally 30 days before surgery in all patients with atherosclerotic cardiovascular disease, especially those undergoing vascular surgery 5, 4
• Use long-acting formulations (e.g., fluvastatin 80 mg/day or atorvastatin) 5
• Statins reduce postoperative cardiovascular complications and mortality (1.8% vs 2.3% without statins, p<0.001) 4

Antiplatelet therapy 1, 4:

• Do NOT routinely start low-dose aspirin (100 mg/day) preoperatively—it does not decrease cardiovascular events but increases surgical bleeding 4
• Continue aspirin in patients with established indications (prior MI, coronary stents) only if bleeding risk is acceptable 1

Diabetes management 1:

• Optimize glycemic control while avoiding hypoglycemia 1
• Insulin-dependent diabetes is a clinical risk factor requiring closer perioperative monitoring 1

Common Pitfalls to Avoid

• Ordering routine stress tests: Stress testing in low-risk patients (0-2 risk factors) delays surgery without improving outcomes 5, 4
• Prophylactic coronary revascularization: Does not reduce perioperative risk and exposes patients to procedural complications and bleeding risk from antiplatelet therapy 5, 4, 6
• Starting high-dose beta-blockers immediately preoperatively: Increases stroke and death risk 4
• Routine aspirin initiation: Increases bleeding without reducing cardiovascular events 4
• Obtaining echocardiography in asymptomatic patients: Not indicated unless evaluating for heart failure or severe valvular disease 1
• Delaying surgery for cardiac testing in patients with excellent functional capacity: Patients who can climb 2+ flights of stairs can proceed directly to surgery 1, 2