Myocardial infarction after noncardiac surgery

Background

MINS is the most common cardiovascular complication after noncardiac surgery, with incidence of about 18%
MINS refers to an acute elevation of troponin due to myocardial ischemia occuring during or within 30 days of noncardiac surgery

Elevated troponin within 30 days of non-cardiac surgery
Can be asymptomatic (about 90% of cases), but also includes traditional acute coronary syndrome

Increased in-hospital mortality (8% vs 0.4%), 12-month mortality (21% vs 5%), and risk of short-term and long-term cardiovascular complications
The degree of troponin elevation corresponds inversely with outcomes

Based on troponin thresholds
- Non-high-sensitivity troponin T (TnT) ≥0.03 ng/mL
- High-sensitivity troponin T (hsTnT) 20 to <65 ng/L with absolute change of ≥5 ng/L, or ≥65 ng/L

Routine screening should be done for patients with RCRI ≥1, age ≥65 years, age 45-64 years with significant cardiovascular disease, elevated preoperative NT-proBNP ≥300 ng/L, or elevated BNP ≥92 mg/L
For these high-risk patients, follow troponin and ECG daily after surgery, with for 48 to 72 hours or until peak

Assess for high risk signs or symptoms, including persistent chest pain, ST elevation, new LBBB, dynamic ECG changes, or hemodynamic instability
- Consider inpatient echocardiogram, cardiac catheterization, and Cardiology consultation
- Consider risk stratification with cardiac stress testing
Manage non-ischemic causes of troponin rise, including anemia, tachycardia, hypotension, pulmonary embolism, and sepsis
Start cardioprotective medications, including moderate-to-high dose statin and low-dose aspirin
- Consider adding intermediate dose dabigatran
- Timing of antiplatelets and anticoagulant depends on bleeding risk and should be discussed with the surgeon
Counsel patient on modifiable risk factors for cardiovascular disease

Follow up within 2 to 4 weeks if possible
Risk stratification with non-invasive cardiac testing stress echo, nuclear stress test, or coronary CT angiography
- Consider PET, if available
Consider routine reassessment for at least 1 year, especially if there were high-risk features