[Effect analysis of myectomy guided by personalized three-dimensional reconstruction and printing in the treatment of obstructive hypertrophic cardiomyopathy].

Objective: To examine the clinical efficacy of myectomy guided by personalized three-dimensional reconstruction and printing for patients with obstructive hypertrophic cardiomyopathy. Methods: The clinical data of 28 patients with obstructive hypertrophic cardiomyopathy, who underwent septal myectomy guided by personalized three-dimensional reconstruction and printing in the Department of Cardiaovascular Surgery, Guangdong Provincial People's Hospital from May 2020 to December 2021, were retrospectively analyzed. There were 14 males and 14 females, aging (51.1±14.0) years (range: 18 to 72 years). Enhanced cardiac computed tomography images were imported into Mimics software for preoperative three-dimensional reconstruction. The direction of the short axial plane of each segment was marked perpendicularly to the interventricular septum on the long axial plane of the digital cardiac model, then the thickness was measured on each short axial plane. A figurative digital model was used to determine the extent of resection and to visualize mitral valve and papillary muscle abnormalities. Correlation between the length, width, thickness, and volume of the predicted resected myocardium and those of the surgically resected myocardium was assessed by Pearson correlation analysis or Spearman correlation analysis. The accuracy of detecting mitral valve and papillary muscle abnormalities of transthoracic echocardiography and three-dimensional reconstruction was also compared. Results: There was no death or serious complications like permanent pacemaker implantation, re-sternotomy for bleeding, low cardiac output syndrome, stroke, or multiple organ dysfunction syndromes in the whole group. Namely, the obstruction of the left ventricular outflow tract was effectively relieved. The systolic anterior motion of the anterior mitral valve leaflet was absent in all patients after myectomy. The length, width, and thickness of the predicted resected myocardium by three-dimensional reconstruction were significantly positively correlated with the length (R=0.65, 95%CI: 0.37 to 0.82, P<0.01), width (R=0.39, 95%CI: 0.02 to 0.67, P<0.01), and thickness (R=0.82, 95%CI: 0.65 to 0.92, P<0.01) of the surgically resected myocardium, while the relation of the volume of the predicted resected myocardium and the volume of the surgically resected myocardium was a strong positive correlation (R=0.88, 95%CI: 0.76 to 0.94, P<0.01). Importantly, the interventricular septal myocardial thickness measured by preoperative transthoracic echocardiography showed a moderate positive correlation with the volume of surgically resected myocardium (R=0.52, 95%CI: 0.19 to 0.75, P<0.01). During a follow-up of (14.4±6.8) months (range: 3 to 22 months), no death occurred, and 1 patient was readmitted for endocardial radiofrequency ablation due to atrial fibrillation. Conclusion: Personalized three-dimensional reconstruction and printing can not only visualize the intracardiac structure but also guide septal myectomy by predicting the thickness, volume, and extent of resected myocardium to achieve ideal resection.目的： 探讨个性化三维重建及打印技术指导下室间隔心肌切除术治疗梗阻性肥厚型心肌病的临床效果。 方法： 回顾性分析2020年5月至2021年12月于广东省人民医院心外科接受个性化三维重建和打印技术指导下室间隔心肌切除术治疗的28例梗阻性肥厚型心肌病患者的临床资料。男性14例，女性14例，年龄（51.1±14.0）岁（范围：18~72岁），术前将心脏增强CT图像导入Mimics软件重建，于心脏数字模型的左心室长轴面上标记垂直于各节段室间隔的短轴面方向，并于相应的短轴面上测量室间隔厚度。预测切除心肌的厚度并利用具象化的数字模型确定切除范围，并可视化二尖瓣和乳头肌异常。通过Pearson相关分析或Spearman相关分析评估预测切除室间隔心肌的长度、宽度、厚度及体积与实际切除室间隔心肌的长度、宽度、厚度及体积的相关性。 结果： 全组患者无死亡，无永久起搏器植入、再次开胸止血、低心排血量综合征、卒中和多器官功能障碍综合征等严重并发症。全组患者术后左心室流出道梗阻有效解除。三维重建预测切除心肌的长度、宽度和厚度与实际切除心肌的长度（R=0.65，95%CI：0.37~0.82，P<0.01）、宽度（R=0.39，95%CI：0.02~0.67，P<0.01）和厚度（R=0.82，95%CI：0.65~0.92，P<0.01）均呈正相关。预测切除心肌的体积与实际切除心肌的体积呈高强度正相关（R=0.88，95%CI：0.76~0.94，P<0.01）。术前超声心动图测量的室间隔心肌厚度与实际切除室间隔心肌的体积呈中等强度正相关（R=0.52，95%CI：0.19~0.75，P<0.01）。随访（14.4±6.8）个月（范围：3~22个月），无患者死亡，1例患者因心房颤动再次入院行心内膜射频消融术。 结论： 个性化三维重建及打印技术能将心内结构可视化，并通过预测切除心肌的厚度、体积及范围指导室间隔心肌切除术，临床效果满意。.