Thrombus aspiration during primary percutaneous coronary intervention improves myocardial reperfusion and reduces infarct size: the EXPIRA (thrombectomy with export catheter in infarct-related artery during primary percutaneous coronary intervention) prospective, randomized trial

Abstract

Objectives: The purpose of this study was to evaluate the impact on myocardial perfusion and infarct size as assessed by contrast-enhanced magnetic resonance imaging (CE-MRI) of a manual thrombectomy device, Export Medtronic (EM) (Medtronic Inc., Minneapolis, Minnesota), as adjunctive therapy in primary percutaneous coronary intervention (PPCI) in a subset of patients with anterior ST-segment elevation myocardial infarction (STEMI).

Background: PPCI may cause thrombus dislodgment, leading to microvascular damage.

Methods: One hundred seventy-five STEMI patients were randomly assigned to standard percutaneous coronary intervention (PCI) (n = 87) or EM-PCI (n = 88). The primary end points were the occurrence of myocardial blush grade > or =2 and the rate of 90-min ST-segment resolution >70%. The CE-MRI substudy was performed in 75 patients with anterior STEMI to assess microvascular obstruction and infarct size.

Results: Myocardial blush grade > or =2 and ST-segment resolution occurred more frequently in the EM-PCI group (88% vs. 60%, p = 0.001; and 64% vs. 39%, p = 0.001). In the acute phase, microvascular obstruction extent was significantly lower in the EM-PCI group and at 3 months, infarct size was significantly reduced only in the EM-PCI group. A lower incidence of cardiac death in the EM-PCI group (4.6% vs. 0%, log-rank test p = 0.02) was observed at 9 months.

Conclusions: Thrombectomy prevents thrombus embolization and preserves microvascular integrity reducing infarct size, and it therefore represents an useful adjunctive therapy in PPCI.