ST segment depression

Introduction

Depression of the ECG ST segment.

Etiology

• subendocardial injury
• may occur as reciprocal ST segment depression in conjunction with ST segment elevation in other leads

Laboratory

• serum troponin I

Diagnostic procedures

• electrocardiogram:
  • ST segment depression
  • 0.5 mm in 2 or more contiguous leads is significant

Management

• defines high cardiac risk patients
• in conjunction with chest pain treat as NSTEMI
  • administer P2Y12 inhibitor & heparin in high risk patients
    • LMW heparin if normal kidney function, otherwise unfractionated heparin
    • patient should have received aspirin
    • nitrates as needed for angina pectoris
    • add beta-blocker as tolerated
  • admit to hospital
  • cardiac stress testing in low-risk patients
• percutaneous coronary intervention not indicated within 6 hours in the absence of ST segment elevation or LBBB

More general terms

• ECG ST segment

Additional terms

• ECG changes in myocardial ischemia
• ST segment elevation