Safety of lone thrombus aspiration without concomitant coronary stenting in selected patients with acute myocardial infarction.

Aims: Although the benefit of concomitant thrombus aspiration (TA) in primary percutaneous coronary intervention (PPCI) treatment of acute ST-segment elevation myocardial infarction (STEMI) has been demonstrated, very little information is available on its safety as a lone revascularisation technique in this setting. We present our experience in a cohort of patients with STEMI treated only with TA, without concomitant interventional devices.
Methods and Results: In 28 patients with STEMI, PPCI was performed using only TA on the grounds of an excellent angiographic result and in order to avoid the potential risks associated with balloon dilatation or stenting. The patients were younger than in the overall PPCI population (n=1,737) at our institution (52±18 vs. 63±14 years, p<0.001), with a history of atrial fibrillation in six (21%), cocaine abuse in three (11%) and mechanical cardiac valves in two (7%). Twenty-eight patients (89%) presented STEMI with Killip class I, two (7%) with cardiogenic shock, and two (7%) with sudden cardiac death. A significant reduction in TIMI thrombus grade (5 [4-5] to 1 [0-1.75], p<0.001) and coronary stenosis percentage (%) (87.2±21.3 to 11.3±0.9, p<0.001) as well as an increase in final TIMI flow (0 [0-2] to 3 [3-3], p<0.001) and minimum luminal diameter (mm) (0.89±1.01 to 2.42±0.70, p<0.001) were noted after TA. Transient no-reflow phenomenon, residual intracoronary thrombus and minor distal thrombus embolisation were observed in two (7.1%), 11 (39.3%) and 10 (25.7%) patients, respectively. All but one patient remained asymptomatic during hospital admission. Scheduled control angiography was performed 6±2 days (min-max, 3-10 days) after PPCI in 11 (39%) patients, demonstrating coronary artery patency and TIMI flow grade 3 in all patients. During clinical follow-up, successfully performed in all patients at 40±23 months (min-max, six to 95 months), there was one sudden cardiac death (4%) and three (11%) non-cardiac deaths. One patient (4%) was admitted with non-STEMI (new coronary angiogram without stenosis) and the remaining 22 (78.5%) remained asymptomatic and free of cardiac events.
Conclusions: Our series suggests that lone TA might be safely performed as a primary revascularisation procedure in STEMI in selected cases. Further information based on additional and larger studies is recommended to confirm our findings.