부산대학교 도서관

Purpose: The EXPIRA already showed that thrombectomy during primary PCI improves myocardial reperfusion, prevents distal embolization and reduces infarct size by preserving microvascular integrity. Tissue Doppler Imaging (TDI) and 2D Speckle Tracking Echocardiography (2DSTE), by measuring myocardial deformation with global and regional longitudinal systolic strain (LSS), could be a useful tool to detect microvascular damage in patients treated with standard PCI (S-PCI) compared with thrombus aspiration during PCI (Export Medtronic, EM-PCI).Methods: Out of 175 pts from the EXPIRA trial we selected 75 patients (mean age 66.3±10.6) with anterior STEMI (6 hours from symptoms onset) and an occlusive thrombus at angiography. In this group, 38 pts were submitted to thromboaspiration (group-T) and 37 pts to standard PCI (group-C). A complete echocardiographic examination was performed within 90ʼafter primary PCI. Regional (Wall Motion Score Index, WMSI) and global (LVEF%) myocardial function, TDI-derived global strain were evaluated. By using 2DSTE global and regional longitudinal peak systolic strain in a 16 segments model were analyzed.Results: After trombectomy a TIMI II flow was present in in 26.3 vs 16.2% (p=ns), TIMI III was 71.5 vs 29.7% (T vs C p=0.0005). Postprocedural MBG 2 was 86.8% vs 59.4% (p=0.009) and 90ʼ ST-segment resolution was 84.2% vs 40.5% (T vs C, respectively, p= 0.0001). There were no significant differences in terms of LVEF (41,9% in group T vs 40,8% in group C) and WMSI (1,49 in S-PCI vs 1,69 in EM-PCI). A significant difference in terms of global mean systolic TDI-derived strain between pts treated with thrombectomy (-18.1%) and pts treated with standard PCI (-15.4%) was detected. In pts with adequate endocardial border visualization, by using 2DSTE, a global longitudinal strain of -17,75% in EM-PCI vs -12,5% in S-PCI group (p=0.02) was observed. Considering selectively the infarct-related areas, differences became more significant showing LSS-13,25% in group-T compared with LSS -10,65% in group-C (p=0.006).Conclusions: Compared with conventional stenting, a pre-treatment with thrombectomy during primary PCI, improves epicardial flow and procedural outcomes in terms of MBG 2 and 90ʼ ST resolution achievement. The difference observed in terms of LSS between the two groups suggests a rapid and better segmental function recovery in patients treated with thrombus aspiration. LSS after primary PCI could be a very sensitive non-invasive marker of microvascular dysfunction independent from LVEF and WMSI.