NCT03998319

A Study of Low-dose Intracoronary Thrombolytic Therapy in STEMI (Heart Attack) Patients.

A Randomised Trial to Evaluate the Efficacy of Low-dose Intracoronary Tenecteplase in ST-Elevation Myocardial Infarction (STEMI) Patients With High Microvascular Resistance Post-percutaneous Coronary Intervention (PCI).

• Status: Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 445 (estimated)
• Sponsor: University of Sydney · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

Heart attacks are caused by a blood clot blocking the blood vessels of the heart, preventing blood getting to the heart muscle. Opening up the artery with a balloon (angioplasty) and a small mesh tube (stent) although life saving can cause this clot to break up and get washed downstream, which can make the heart attack worse. The investigators can measure the amount of damage caused to the microcirculation by calculating the IMR (Index of Microcirculatory resistance). This can be measured by a wire in the coronary artery with a pressure sensor at the tip. If the IMR is elevated, it is suggestive of extensive microcirculatory damage. A clot dissolving medicine can be administered in the artery to try and reduce the IMR which can reduce damage to the heart muscle and improve outcomes. Impaired microcirculatory perfusion in patients as a result of ST-elevation myocardial infarction (STEMI) is associated with poor clinical outcomes. This project seeks to identify patients with impaired microcirculatory perfusion after STEMI and to assess whether acute improvement in microcirculatory perfusion in these patients by the use of intracoronary thrombolytic therapy results in improved clinical outcomes.

Detailed description

Patients presenting to the participating hospitals with a heart attack will be approached to participate in the study. After angioplasty has been performed, the IMR will be measured in the infarct related artery. If the IMR is \>32 patients will be randomised to receive intracoronary clot dissolving therapy in the form of low dose tenecteplase (TNK) or water as a placebo. Patients who have an IMR ≤32 will be followed up in a registry. Cardiac enzymes will be measured at baseline and discharge. Randomised participants will receive a cardiac MRI at discharge (3-7 days post primary PCI) and at 6 months post PCI. All participants will be followed up at 30 days, and 6, 12 and 24 months following discharge.

Conditions

• STEMI
• Elevated IMR (>32)

Interventions

Type	Name	Description
DRUG	Tenecteplase (1/3 systemic weight based dose)	50mg reconstituted to 20mL for intracoronary infusion at 1/3 weight based dose.
OTHER	Sterile water for injection (WFI)	Placebo comparative arm.

Timeline

• Start date: 2021-10-14
• Primary completion: 2024-12-31
• Completion: 2026-12-31
• First posted: 2019-06-26
• Last updated: 2024-09-27

Locations

22 sites across 2 countries: Australia, New Zealand

Regulatory

• FDA-regulated drug study