Background: Despite rapid and complete recanalization of infarct-related artery with percutaneous coronary intervention, microvascular integrity is not often preserved. Several mechanical devices have been proposed to prevent distal embolization, but the impact of these devices on myocardial perfusion remains controversial.
Aim: The aim of our study was to assess microvascular damage reduction with quantitative myocardial contrast perfusion echocardiography among patients with the first anterior acute myocardial infarction treated with thromboaspiration during percutaneous coronary intervention.
Methods: Forty-two patients (57.4+/-10 years, 74% males) with first anterior acute myocardial infarction were randomized 1 : 1 to intracoronary thromboaspiration followed by stenting, or to a conventional strategy of stenting alone. Echocardiogram and quantitative myocardial contrast echocardiography were performed 7 days and 1 month later, respectively. Parameter A (reflecting myocardial blood volume), beta (reflecting velocity, myocardial blood flow), and product of A and beta as indicator of myocardial blood flow were analyzed. For each patient mean value of A, beta, and A x beta from all dysfunctional segments was calculated.
Results: The study population was divided into two groups: thromboaspiration (group I, 19 patients) and stenting alone (group II, 23 patients). No difference was observed between the both groups in demographic, clinical, echocardiographic, and angiographic data. Parameter A and A x beta were significantly higher in group I than in group II: 8.58+/-2.54 versus 5.29+/-3.18 dB (P<0.001) and 5.29+/-3.73 versus 2.78+/-3.03 dB/s (P<0.001). Multivariate step-down regression analysis revealed that only thromboaspiration before stenting and lower maximum troponin I have been associated with viability preservation in infarcted region.
Conclusion: Thromboaspiration before stenting in patients with the first anterior myocardial infarction improves myocardial perfusion at the tissue level assessed by quantitative myocardial contrast echocardiography.