Thrombus Aspiration Fails to Reduce Microvascular Obstruction in Subacute STEMI

Routine use of manual thrombus aspiration prior to PCI does not reduce microvascular obstruction compared with PCI alone in patients with subacute STEMI, according to late-breaking findings presented in the Main Arena yesterday. 

In a single-blind study, Steffen Desch, MD, of University of Schleswig-Holstein, Campus Lübeck, in Lübeck, Germany, and colleagues enrolled 152 patients with subacute STEMI (mean age 66) presenting at their center between 12 and 48 hours after symptom onset. Patients were randomized to PCI with thrombus aspiration (n = 70) or standard PCI only (n = 74). Thrombus aspiration was performed prior to the first balloon inflation with a manual aspiration catheter. A minimum of two passages were recommended.

More patients in the thrombus-aspiration group had hypertension (79% vs. 65%), whereas more patients in the standard-PCI group had hyperlipoproteinemia (23% vs. 16%), diabetes (34% vs. 31%) and ongoing signs of ischemia (55% vs. 49%).

In all, 111 patients (thrombus aspiration, n = 56; standard PCI, n = 55) underwent cardiac magnetic resonance (CMR) imaging. There was no difference between the 2 arms with regard to the extent of microvascular obstruction (MVO) on late gadolinium enhancement CMR at day 1 to 4 (primary endpoint). Thrombus aspiration also failed to improve infarct size, LV function, or biomarker levels (Table).

The observation that thrombus aspiration did not improve MVO persisted when researchers analyzed outcomes in several predefined subgroups based on sex (P = .95), diabetes status (P = .29), TIMI thrombus grade (0-4 vs. 5, P = .82), TIMI flow before PCI (0-1 vs. 2-3, P = .53) and use of glycoprotein IIb/IIIa inhibitors (P = .35).

There also was no difference between routine thrombus aspiration and PCI alone for post-PCI grade 3 TIMI flow (79% vs. 69%; P = .44) or myocardial blush grade 3 (70% vs. 67%; P = .83). Rates of all-cause death (3% vs. 5%; P = .68), CV death (3% vs. 4%; P = 1), target vessel revascularization (3% vs. 0%; P = .24), target lesion revascularization (3% vs. 0%; P = .24) and stroke (0% vs. 1%; P = .24) also were similar. No cases of reinfarction or stent thrombosis occurred.

Yet the results still help fill a gap in clinical knowledge, Desch said. “Numerous trials studied manual thrombus aspiration in patients who presented within 12 hours of symptom onset,” he noted. “Although the TASTE trial had a quite liberal inclusion of 24 hours, the actual median between symptom onset and PCI was only 3 hours, so there are basically no data in a timeframe after 12 hours of symptom onset.”

Disclosures:

• Desch reports receiving grant/research support from Medtronic.