Primary angioplasty and routine utilization of thrombus aspiration devices: feasibility and results in a consecutive series of 486 patients.

BACKGROUND

Primary percutaneous transluminal coronary angioplasty (PTCA) is the treatment of choice for acute ST-segment elevation myocardial infarction (STEMI) in high-volume centres with experienced operators, but is often limited by a suboptimal microvascular perfusion due to distal embolization and impaired myocardial perfusion. The present study investigates whether routine use of thrombus aspiration (TA) devices is feasible in daily practice, along with its safety and effectiveness.

METHODS

This study is based on a series of 486 consecutive STEMI patients treated at our single institution by the same three operators (from 2001 to 2005). They underwent primary PTCA with or without TA according to these angiographic features: infarct related artery (IRA) diameter>or=3 mm; thrombotic occlusion or angiographic evidence of thrombus; absence of severe proximal tortuosity or calcification. We evaluate the efficacy of TA in terms of procedural success, coronary thrombolysis in myocardial infarction (TIMI) flow, myocardial blush grade (MBG), resolution>or=50% of ST segment elevation, and clinical events during hospital stay and at 6-month follow-up.

RESULTS

A total of 486 primary PTCAs were performed, 217 (44.6%) with TA as a first device using RESCUE (n=65), EXPORT (n=140) and DIVER-CE (n=12) catheters. In 141 (65%) cases, macroscopic material was aspirated. The patients submitted to TA were more often males (84.7% versus 71.7%, P<0.05) and younger (age: 61.02+/-11.91 versus 64.47+/-10.59 years, P<0.01) than patients treated with traditional PTCA and the IRA was more frequently occluded at angiography (basal TIMI 0: 70.5% versus 47.9%). Application of the TA did not increase the complexity of the procedure (door-to-balloon times, minutes of fluoroscopy and amount of dye). TA alone was effective to restore TIMI 3 flow in 187 cases (86.2%) as a first device and in three other cases (1.4%) after predilatation with balloon. Direct stenting without predilatation was possible in 144 cases (66.4%) after TA. TA was not effective in 27 cases (12.4%) and this subgroup had both angiographic and clinical unfavourable results in comparison with the effective TA group (final TIMI 1 in 11.1% versus 0.5%, P<0.015; final MBG 1 in 55.5% versus 9.5%, P<0.001; lack of ST segment resolution>or=50% in 44.4% versus 7.9%, P<0.001; in-hospital mortality 14.8% versus 2.6%, P<0.05 and mortality at 6 months 18.5% versus 3.1%, P<0.05). In the whole TA population, final TIMI 3 flow was achieved in 203 cases (93.5%), final MBG 3 in 145 cases (66.8%) and ST segment resolution>or=50% in 185 cases (85.2%), in-hospital mortality was 4.1% and cumulative mortality at 6-month follow-up was 5.5%.

CONCLUSIONS

In our case series, 486 consecutive unselected patients with STEMI were treated in a primary PTCA high-volume centre using TA devices. Our study demonstrates that, in STEMI patients treated with primary PTCA, a routine strategy with TA before angioplasty guided by angiographic selection criteria is feasible in almost 50% of cases, is safe and effective, does not increase procedural time and offers good results in terms of tissue perfusion, both epicardial (TIMI flow) and myocardial (MBG, ST regression). When successfully performed, TA identifies a population with favourable in-hospital and 6-month outcome.