Background: Despite recovered normal epicardial coronary flow after primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI), microvascular damage and dysfunction limit the effect of primary PCI. The purpose of this study was to evaluate whether manual thrombectomy can preserve the index of microcirculatory resistance (IMR) after primary PCI in patients with anterior STEMI. Methods: 41consecutive patients (38 men and 3 women; age 52 ± 9 years) with anterior STEMI were enrolled. All patients were randomized into two groups and underwent primary PCI for anterior STEMI: stenting after manual thrombectomy (aspiration group, n=22) and stenting without manual thrombectomy (conventional group, n=19). The thermodilution-derived coronary flow reserve (CFR) and index of microcirculatory resistance (IMR) were measured by using the pressure-temperature sensor-tipped coronary wire at the left anterior descending artery (LAD) after primary PCI. Baseline echocardiography was performed before discharge and follow-up echocardiography was performed 6 months later. Results: There was no significant difference in reperfusion time (onset to balloon time) and CFR (2.01 ± 1.1 vs. 2.08 ± 1.1, p ± 0.831), baseline ejection fraction (EF, 44.5 ± 7.5% vs. 48.0 ± 8.0%, p ± 0.15), baseline wall motion score index (WMSI, 1.52 ± 0.32 vs. 1.46 ± 0.31, p ± 0.59) between two groups. But, there was significant difference in IMR (22.3 ± 8.7 vs. 29.5 ± 11.9, p ± 0.037), ΔEF (follow up EF - baseline EF, 5.86 ± 7.2 vs. 1.29 ± 2.5, p ± 0.011), ΔWMSI (baseline WMSI - follow up WMSI, -0.199 ± 0.242 vs. 0.003 ± 0.075, p ± 0.001) between two groups. Conclusions: Compared with conventional PCI, manual thrombectomy before stenting for patients with anterior STEMI seems to preserve microvascular integrity. Manual thrombectomy as an adjunctive method of primary PCI for acute anterior STEMI might have beneficial efficacy on myocardial microcirculation.
Woo, S. I., Jang, J. H., Kim, S. H., Kim, D.-H., Park, K.-S., Park, S.-D., … Yang, D.-H. (2012). TCT-470 Manual Thrombectomy during Primary Percutaneous Coronary Intervention Can Preserve the Index of Microcirculatory Resistance in Patients with Anterior ST-Segment Elevation Myocardial Infarction. Journal of the American College of Cardiology, 60(17), B135–B136. https://doi.org/10.1016/j.jacc.2012.08.502