Reduced dose tenecteplase and outcomes in elderly ST-segment elevation myocardial infarction patients: Insights from the STrategic Reperfusion Early After Myocardial infarction trial

Abstract

Elderly patients with ST-segment elevation myocardial infarction (STEMI) have worse outcomes and a greater risk of intracranial bleeding than nonelderly patients. Baseline characteristics, clinical outcomes, and the relationship of the tenecteplase (TNK) dose reduction to the efficacy, safety, and electrocardiographic indicators of reperfusion efficacy were evaluated in STEMI patients ≥75 years. The STREAM trial evaluated early presenting STEMI patients who could not undergo primary percutaneous coronary intervention within 1 hour of first medical contact. Because of excess intracranial hemorrhage (ICH) in patients ≥75 years, the dose of TNK was reduced by 50%. Before dose amendment, there were 3 (7.1%) of 42 elderly patients with ICH; 2 of these were fatal, whereas no ICH occurred in the 93 elderly patients who received half-dose TNK postamendment. The median extent of ST-segment elevation resolution (≥50%) and proportion of patients with ≥2 mm in the electrocardiogram lead with greatest ST-segment elevation was comparable in elderly patients preamendment and postamendment (63.2% vs 56.0% and 43.6% vs 40.0%, respectively). Patients requiring rescue coronary intervention after TNK was also similar (42.9% vs 44.1%). The primary composite end point (30-day all-cause death, cardiogenic shock, congestive heart failure, and reinfarction) was 31.0% before versus 24.7% postamendment. Our data, from a modest-sized population of elderly STEMI patients, indicate that half-dose TNK reduces the likelihood of ICH without compromising reperfusion efficacy. These observations are hypothesis generating and warrant further confirmation in randomized clinical trials in the elderly.