McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pa, USA.
J Thorac Cardiovasc Surg. 2013 Aug;146(2):391-9.e1. doi: 10.1016/j.jtcvs.2012.11.013. Epub 2012 Dec 6.
Myocardial infarction (MI) can lead to irreversible adverse left ventricular remodeling resulting in subsequent severe dysfunction. The objective of this study was to investigate the potential for biodegradable, elastomeric patch implantation to positively alter the remodeling process after MI in a porcine model.
Yorkshire pigs underwent a 60-minute catheter balloon occlusion of the left circumflex artery. Two weeks after MI animals underwent epicardial placement of a biodegradable, porous polyurethane (poly(ester urethane)urea; PEUU) patch (MI+PEUU, n = 7) or sham surgery (MI+sham, n = 8). Echocardiography before surgery and at 4 and 8 weeks after surgery measured the end-diastolic area (EDA) and fractional area change (%FAC). All animals were humanely killed 8 weeks after surgery and hearts were histologically assessed.
At 8 weeks, echocardiography revealed greater EDA values in the MI+sham group (23.6 ± 6.6 cm(2), mean ± standard deviaation) than in the MI+PEUU group (15.9 ± 2.5 cm(2)) (P < .05) and a lower %FAC in the MI+sham group (24.8 ± 7.6) than in the MI+PEUU group (35.9 ± 7.8) (P < .05). The infarcted ventricular wall was thicker in the MI+PEUU group (1.56 ± 0.5 cm) than in the MI+sham group (0.91 ± 0.24 cm) (P < .01).
Biodegradable elastomeric PEUU patch implantation onto the porcine heart 2 weeks post-MI attenuated left ventricular adverse remodeling and functional deterioration and was accompanied by increased neovascularization. These findings, although limited to a 2-month follow-up, may suggest an attractive clinical option to moderate post-MI cardiac failure.
心肌梗死(MI)可导致不可逆的左心室重构,从而导致随后的严重功能障碍。本研究的目的是在猪模型中研究可生物降解的弹性体贴片植入对 MI 后重构过程的潜在积极影响。
约克夏猪接受左回旋支动脉 60 分钟导管球囊闭塞。MI 后 2 周,动物接受可生物降解的多孔聚氨基甲酸酯(聚酯氨酯脲;PEUU)贴片的心脏外膜贴附(MI+PEUU,n=7)或假手术(MI+假手术,n=8)。手术前和手术后 4 周和 8 周进行超声心动图检查,测量舒张末期面积(EDA)和面积变化分数(%FAC)。所有动物均在手术后 8 周内人道处死,并进行心脏组织学评估。
在 8 周时,超声心动图显示 MI+假手术组的 EDA 值大于 MI+PEUU 组(23.6±6.6 cm2,均值±标准差)(P<.05),MI+假手术组的%FAC 低于 MI+PEUU 组(24.8±7.6)(P<.05)。MI+PEUU 组的梗死心室壁比 MI+假手术组(1.56±0.5 cm)厚(0.91±0.24 cm)(P<.01)。
MI 后 2 周将可生物降解的弹性体 PEUU 贴片植入猪心脏可减轻左心室不良重构和功能恶化,并伴有新生血管化增加。这些发现虽然仅限于 2 个月的随访期,但可能提示一种有吸引力的临床选择来治疗中度 MI 后心力衰竭。