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

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). PPCI may cause thrombus dislodgment, leading to microvascular damage. 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. 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. Thrombectomy prevents thrombus embolization and preserves microvascular integrity reducing infarct size, and it therefore represents an useful adjunctive therapy in PPCI.