tPA (Alteplase) Dosing for STEMI, Pulmonary Embolism & Stuck Prosthetic Valve

tPA (Alteplase) Dosing for STEMI, Pulmonary Embolism & Stuck Prosthetic Valve

tPA (alteplase) is a fibrin-specific thrombolytic used globally for rapid reperfusion in acute ischemic events. Unlike streptokinase, tPA has no antigenicity, works faster, and produces more targeted clot dissolution.

Below are the standard accepted alteplase regimens for:

STEMI

Acute Pulmonary Embolism

Prosthetic Valve Thrombosis (PVT / stuck valve)

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1. Alteplase Dose for STEMI

Two main regimens are used: the accelerated 90-minute regimen (most common) and the 3-hour regimen.

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A) Accelerated 90-Minute Regimen (Preferred)

Total dose: 100 mg

If weight ≥ 67 kg:

15 mg IV bolus

50 mg over 30 minutes

35 mg over the next 60 minutes

If weight < 67 kg:

15 mg IV bolus

Then 0.75 mg/kg over 30 minutes (max 50 mg)

Then 0.5 mg/kg over 60 minutes (max 35 mg)

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B) 3-Hour Regimen (Alternative)

Total dose: 100 mg over 3 hours

1 mg/kg over 60 minutes

Then 1 mg/kg over the next 2 hours

(Max total 100 mg)

Used when accelerated protocol is not feasible.

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2. Alteplase Dose for Acute Pulmonary Embolism

For massive PE (with hypotension, shock), tPA improves survival by rapidly reducing pulmonary pressures.

Standard PE Regimen

100 mg IV over 2 hours

(Heparin is held during infusion and restarted afterwards when aPTT < 2× normal.)

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Alternative Low-Dose / Weight-Based Regimens

Used selectively in high-bleeding-risk patients:

50 mg over 2 hours

OR 0.6 mg/kg over 15 minutes (max 50 mg)

These are institution-dependent.

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3. Alteplase for Stuck Prosthetic Valve (Prosthetic Valve Thrombosis)

tPA is often preferred over streptokinase because it is fibrin-specific, faster, and sometimes safer in controlled low-dose infusions.

There are three accepted clinical strategies:

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A) “Ultraslow” Low-Dose Infusion (most endorsed today)

1 mg/hour for 25 hours (total 25 mg)

Followed by repeat cycles depending on response.

This approach (e.g., TROIA and PROMETEE protocols) reduces:

Major bleeding

Embolization

Need for surgery

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B) Slow Infusion, Low Dose

25 mg alteplase infused over 6 hours

Repeat cycle up to 2–3 times if needed

No bolus

Used for left-sided valves, especially mitral.

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C) Accelerated Regimen

Used in right-sided valves or when rapid thrombolysis is necessary.

10 mg bolus, then

90 mg infusion over 2 hours

(Max total 100 mg)

Higher embolization risk → used only in selected cases.

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Summary Table

Condition Standard tPA Dose Alternative Dose

STEMI 100 mg (15 mg bolus → 50 mg/30 min → 35 mg/60 min) 100 mg over 3 hours

PE 100 mg over 2 hours 50 mg over 2 hr OR 0.6 mg/kg over 15 min

Stuck Valve 1 mg/hr × 25 hr (ultraslow) 25 mg/6 hr OR 100 mg over 2 hr