What are the contraindications for TNKase (tenecteplase)?

Contraindications for TNKase (Tenecteplase)

TNKase (tenecteplase) is absolutely contraindicated in patients with active internal bleeding, history of cerebrovascular accident, intracranial or intraspinal surgery or trauma within 2 months, intracranial neoplasm/arteriovenous malformation/aneurysm, known bleeding diathesis, and severe uncontrolled hypertension. 1

Absolute Contraindications

• Any prior intracranial hemorrhage 2
• Known structural cerebral vascular lesion (e.g., arteriovenous malformation) 2, 1
• Known malignant intracranial neoplasm (primary or metastatic) 2
• Ischemic stroke within 3 months 2
• Suspected aortic dissection 2
• Active bleeding or bleeding diathesis (excluding menses) 2, 1
• Significant closed-head or facial trauma within 3 months 2
• Intracranial or intraspinal surgery within 2 months 2, 1
• Severe uncontrolled hypertension (unresponsive to emergency therapy) 2, 1

Relative Contraindications

• History of chronic, severe, poorly controlled hypertension 2
• Significant hypertension on presentation (SBP >180 mm Hg or DBP >110 mm Hg) 2
• History of prior ischemic stroke >3 months 2
• Dementia 2
• Known intracranial pathology not covered in absolute contraindications 2
• Traumatic or prolonged (>10 min) cardiopulmonary resuscitation 2
• Major surgery (<3 weeks) 2
• Recent (within 2 to 4 weeks) internal bleeding 2
• Noncompressible vascular punctures 2
• Pregnancy 2
• Active peptic ulcer 2
• Current use of oral anticoagulant therapy 2

Special Considerations

Bleeding Risk

• TNKase can cause serious bleeding complications, including intracranial hemorrhage and fatal bleeding 1
• Concomitant use of medications that impair hemostasis (anticoagulants, antiplatelet agents) increases bleeding risk 1
• Female patients >75 years of age who weigh <67 kg are at particularly high risk for bleeding complications 3

Thromboembolism Risk

• Increased risk of thromboembolic events in patients with high likelihood of left heart thrombus (e.g., mitral stenosis, atrial fibrillation) 1

Other Potential Complications

• Cholesterol embolization has been reported with thrombolytic agents 1
• Reperfusion-related arrhythmias may occur (sinus bradycardia, accelerated idioventricular rhythm, ventricular premature depolarizations, ventricular tachycardia) 1
• Hypersensitivity reactions including urticaria and anaphylaxis have been reported 1

Timing Considerations

• TNKase is indicated for use within 12 hours of symptom onset in STEMI 2, 4
• Use beyond the 12-hour window should only be considered in specific circumstances where benefits may outweigh risks, such as in symptomatic STEMI patients with large areas of myocardium at risk or hemodynamic instability when PCI is unavailable 4

Clinical Decision-Making Algorithm

1. Assess for absolute contraindications - presence of ANY absolute contraindication prohibits TNKase use 1
2. Evaluate relative contraindications - carefully weigh risk-benefit ratio 2
3. Consider patient-specific bleeding risk factors (age, weight, gender, blood pressure) 3
4. Assess time from symptom onset (optimal benefit within 12 hours) 2
5. Consider alternative reperfusion strategies (primary PCI) when available 4

By carefully screening for these contraindications and following appropriate protocols, clinicians can optimize the safety profile of TNKase while maintaining its effectiveness in appropriate patients.