RESUMO
AIM: We have recently developed a novel method transmyocardial drilling revascularization (TMDR) combined with heparinized bFGF-incorporating degradable tubular stent implantation to revascularize ischemic myocardium. The aim of the present study was to compare the effect of this new method on left ventricular (LV) remodeling and global function to traditional transmyocardial revascularization (TMR) in acute myocardial ischemia. METHODS: Eighteen miniswine underwent ligation of the left anterior descending (LAD) at the mid-third and were divided into three groups (N.=6 in each group): no treatment (control), TMDR (T), and TMDR+stent implantation (TS) groups. Two channels with 3.5 mm in diameter were established (T and TS groups), followed by implantation of two stents (TS group). LV function, myocardial perfusion, expression of von Willebrand factor (vWF), transforming growth factor-ß3 (TGF-ß3), vascular endothelial growth factor (VEGF), interleukin-1beta (IL-1ß), vascular density, and histologic and morphologic analyses were evaluated at different time-points. RESULTS: Six weeks post-treatment, there were no differences between T and control groups. TS group showed significant improvement compared to T group as to: expressions of TGF-ß3, VEGF, vWF and IL-1ß (P<0.001), neovascular density (2.561±391 vs. 6.201±443 pixels/hpf, P<0.001), myocardial viability (18.913±2775 vs. 94.800±14.076 pixels/hpf, P<0.001), and dp/dtmax (1.735±161 vs. 2.242±223 mmHg/s, P<0.001), Further, there were significant decreases in changes of Mass Defect Percent (2.05±0.22% vs. -1.79±0.45%, P<0.001) and LV end diastolic volume (164.83±10.74 vs. 147.00±7.32 mL, P=0.048) in the TS group. CONCLUSION: TMDR and stent implantation is more effective in enhancement of myocardial viability, improvement of global LV function, and attenuation of LV remodeling than TMDR.
