目的 探讨可注射导电水凝胶聚吡咯-壳聚糖（Polypyrrole⁃Chitosan，PPY⁃CHI）对慢性心肌梗死后心脏功能长期改善的有效性及机制。方法 通过将聚吡咯嫁接到壳聚糖（Chitosan，CHI）骨架上， 合成导电复合物 PPY⁃CHI。在体内，采用大鼠慢性心肌梗死模型，将梗后 SD 雌性大鼠随机分为 3 组（PPY⁃ CHI、CHI 及 Saline 组，n = 5）。4 周后，分别在心肌梗死区及周边植入 PPY⁃CHI。用超声、马松染色、免疫荧 光和心肌电阻率评估心功能长期改善情况。结果 移植生物材料 22 周后，体内评估发现，与注射 CHI 和 Saline 相比，心肌内注射 PPY⁃CHI 具有更低的组织电阻，毛细血管密度大大增加，瘢痕区心室壁厚度显著 增加，LVFS 较梗后增加（10.6 ± 0.55）%。结论 心肌内注射 PPY⁃CHI 促进血管生成，降低瘢痕区组织电阻 和抑制心室重塑，加强慢性心肌梗死后心功能的恢复。 

Objective To investigate the efficacy and mechanism of injectable conductive hydrogel Polypyrrole⁃Chitosan（PPY⁃CHI）on long⁃term improvement of cardiac function after chronic myocardial infarction. Methods PPY⁃CHI，a conductive complex，was synthesized by coupling Polypyrrole to a Chitosan（CHI）back⁃ bone. A rat chronic myocardial infarction model was constructed in vivo，post⁃infarction SD female rats were ran⁃ domly divided into three groups（PPY⁃CHI，CHI and Saline groups，n = 5）. PPY⁃CHI was implanted in and around the infarct area four weeks later. Long⁃term improvement in cardiac function was assessed by ultrasound，Masson staining，immunofluorescence and myocardial resistivity. Results After 22 weeks of transplantation of the bioma⁃ terials，in vitro evaluation revealed that intracardiac injection of PPY⁃CHI had lower tissue resistance ，greatly increased capillary density，significantly increased ventricular wall thickness in the scar area，and a（10.6 ± 0.55）% increase in LVFS compared to post ⁃infarction compared to CHI and Saline injections. Conclusions Intracardiac injection of PPY ⁃CHI promoted angiogenesis，reduced tissue resistance in the scar region，and inhibited adverse ventricular remodeling，which enhancethe recovery of cardiac function after chronic infarction.