Tenecteplase Administration for STEMI
Tenecteplase is administered as a single intravenous weight-based bolus over 5–10 seconds, not as an infusion, for acute ST-segment-elevation myocardial infarction. 1, 2
Administration Method
Tenecteplase is given as a rapid single bolus injection over 5–10 seconds, contrasting sharply with alteplase which requires a 90-minute infusion regimen. 1, 2, 3
The entire dose is delivered as one rapid push; no infusion pump is required and the drug must not be diluted for infusion over time. 2
This single-bolus approach eliminates infusion-related delays, reduces medication administration errors, and provides significant workflow advantages, particularly in centers planning patient transfer or endovascular therapy. 2
Weight-Based Dosing Regimen
The weight-tiered dosing for STEMI is standardized across major guidelines: 1, 4
| Patient Weight | Tenecteplase Dose | Volume (mL) |
|---|---|---|
| <60 kg | 30 mg | 6 |
| 60–69 kg | 35 mg | 7 |
| 70–79 kg | 40 mg | 8 |
| 80–89 kg | 45 mg | 9 |
| ≥90 kg | 50 mg | 10 |
This corresponds to approximately 0.5 mg/kg (maximum 50 mg) for STEMI patients. 2, 3
Precise weight measurement is not mandatory; estimated weight can be used to avoid treatment delays, as the tiered dosing system accommodates reasonable estimates. 2
Pharmacokinetic Rationale
Tenecteplase exhibits a fourfold slower plasma clearance (105 mL/min) compared to alteplase, with a mean initial half-life of 17–24 minutes and terminal half-life of 65–132 minutes. 5, 6
The drug's 80-fold reduced binding to PAI-1 and 6-fold prolonged plasma half-life (22 minutes vs 3.5 minutes for alteplase) enable single-bolus administration. 5
Systemic exposure to tenecteplase at all times after bolus administration is higher than for alteplase 100 mg infusion, allowing more rapid restoration of coronary patency. 5
Timing and Clinical Context
Administer immediately after STEMI diagnosis when primary PCI cannot be performed within 120 minutes of first medical contact. 1, 4
Treatment is recommended within 12 hours of symptom onset, with greatest benefit occurring with earlier administration. 4
For patients presenting very early (<2 hours) with large infarct and low bleeding risk, consider fibrinolysis if time to balloon inflation exceeds 90 minutes. 4
Critical Distinction: STEMI vs Stroke Dosing
The STEMI dose (0.5 mg/kg, maximum 50 mg) must never be used for acute ischemic stroke. 2
For stroke, the dose is 0.25 mg/kg (maximum 25 mg) administered as a bolus over 5–10 seconds. 2
Using the higher STEMI dose for stroke is not supported by evidence and may increase bleeding risk. 2
Common Pitfalls to Avoid
Do not observe after administration to assess clinical response before proceeding to mechanical thrombectomy—this delays definitive treatment and worsens outcomes. 1
Do not administer as an infusion; the entire therapeutic advantage of tenecteplase over alteplase is lost if given over time rather than as a rapid bolus. 2, 3
Do not use tenecteplase as facilitated PCI (administering thrombolytic before planned primary PCI with anticipated delay of 1–3 hours)—the ASSENT-4 PCI trial showed increased mortality (6.7% vs 4.9%) and worse composite outcomes with this strategy. 3