Contraindications to Thrombolytic Therapy in STEMI
Thrombolytic therapy is absolutely contraindicated in patients with any prior intracranial hemorrhage, ischemic stroke within 3 months, known structural cerebral vascular lesions, active bleeding, or severe uncontrolled hypertension, and should never be administered to patients with ST-segment depression on ECG (except true posterior MI or ST elevation in aVR). 1, 2, 3
Absolute Contraindications
The following are absolute contraindications where thrombolytic therapy must not be administered 1, 2, 3, 4:
Neurological Contraindications
- Any prior intracranial hemorrhage at any time in the patient's history 1, 2, 3
- Ischemic stroke within the past 3 months 1, 2, 3
- Known structural cerebral vascular lesion including arteriovenous malformation or aneurysm 1, 2, 4
- Known malignant intracranial neoplasm (primary or metastatic) 1, 2
- Intracranial or intraspinal surgery within the past 2 months 1, 2, 4
- Significant closed-head or facial trauma within 3 months 1
Bleeding-Related Contraindications
- Active internal bleeding (excluding menses) 1, 2, 4
- Known bleeding diathesis including thrombocytopenia or coagulopathy 1, 2, 4
Cardiovascular Contraindications
- Suspected aortic dissection 1
- Severe uncontrolled hypertension unresponsive to emergency therapy 1, 2, 4
ECG-Based Absolute Contraindication
- ST-segment depression on ECG is a Class III (Harm) contraindication, as fibrinolytic therapy provides no benefit and may cause harm in NSTEMI 1, 2, 3
Critical Exception: ST depression is acceptable only when it represents true posterior (inferobasal) MI with posterior ST elevation, or when associated with ST elevation in lead aVR suggesting left main or severe multivessel disease 1, 2, 3
Agent-Specific Contraindication
- Prior streptokinase treatment within the previous 6 months is an absolute contraindication to repeat streptokinase due to risk of serious allergic reaction 1
Relative Contraindications
These conditions require careful risk-benefit assessment but are not absolute prohibitions 1, 2:
Hypertension
- History of chronic, severe, poorly controlled hypertension 1
- Significant hypertension on presentation (SBP >180 mm Hg or DBP >110 mm Hg) 1
Neurological History
- History of prior ischemic stroke >3 months ago 1
- Dementia 1
- Known intracranial pathology not covered in absolute contraindications 1
Recent Procedures and Trauma
- Traumatic or prolonged CPR (>10 minutes) 1
- Major surgery within the past 3 weeks 1
- Recent internal bleeding (within 2 to 4 weeks) 1
- Noncompressible vascular punctures 1
Other Medical Conditions
Clinical Decision-Making Algorithm
When evaluating a STEMI patient for thrombolytic therapy, follow this sequence 1, 2, 3:
Confirm STEMI diagnosis: ST-segment elevation in two contiguous leads or new left bundle branch block with symptoms ≤12 hours 1
Check ECG pattern: If ST depression is present (without posterior MI or aVR elevation), stop—thrombolysis is contraindicated 1, 2, 3
Assess for absolute contraindications: Any single absolute contraindication eliminates thrombolysis as an option 1, 2
Evaluate relative contraindications: Weigh bleeding risk against ischemic risk based on infarct size, hemodynamic status, and time from symptom onset 1
Consider timing: Primary PCI is preferred if available within 120 minutes of first medical contact; otherwise proceed with thrombolysis if no contraindications exist 1, 2, 3
Common Clinical Pitfalls
Age is not a contraindication. Elderly patients (>75 years) are frequently undertreated despite having the highest absolute mortality benefit from reperfusion therapy 1. Only 9% of elderly patients have absolute contraindications to thrombolysis 1.
Do not withhold thrombolysis based solely on relative contraindications in patients with large infarcts or hemodynamic instability when PCI is unavailable, as the mortality benefit typically outweighs bleeding risk 1, 3.
Cardiogenic shock is not a contraindication. Patients with STEMI and cardiogenic shock who are unsuitable for PCI or CABG should receive fibrinolytic therapy 1.
Recent surgery timing matters. Surgery within 3 weeks is a relative contraindication, but intracranial/intraspinal surgery within 2 months is an absolute contraindication 1.
Presentation time beyond 12 hours is not an absolute contraindication if the patient has ongoing ischemia, large area of myocardium at risk, or hemodynamic instability and PCI remains unavailable 1, 3, 5.