Ponnusamy Shunmuga Sundaram, Murugan Mariappan, Ganesan Vithiya, Vijayaraman Pugazhendhi
Department of Cardiology, Velammal Medical College, Madurai, India.
Department of Radiodiagnosis, Velammal Medical College, Madurai, India.
J Cardiovasc Electrophysiol. 2023 Mar;34(3):760-764. doi: 10.1111/jce.15853. Epub 2023 Feb 14.
Presence of scar at the implantation-site is considered as a major factor in determining the success of left bundle branch pacing (LBBP). We aimed at analyzing the predictors of procedural failure in patients with scarred-left ventricle (LV) as demonstrated by cardiac-magnetic resonance-imaging (CMR).
This was a retrospective, observational single-center-study that included consecutive cardiomyopathy patients with LV-scar as demonstrated by late-gadolinium-enhancement (LGE) in CMR requiring LBBP. Procedural-failure was defined as the inability to penetrate the septum to reach the LV subendocardium RESULTS: A total of 25 cardiomyopathy patients demonstrated LGE in CMR and were included in the study. LBBP was successful in 16 patients (group-I; 64% acute-procedural-success). In the remaining 9 patients (group-II) lead could not be penetrated and hence biventricular-pacing was done. LBBP resulted in reduction in QRS-duration and improvement in LV ejection fraction in group-I patients during a mean follow-up of 11.2 ± 3.7 months. Computed-tomography-angiography after LBBP showed the successful lead deployment site (LBBP-Zone) as the overlapping areas of inferior aspect of antero-septum and superior aspect of infero-septum (segment 2/3; AHA-model) in short-axis view(figure-1C). CMR showed LGE in significantly more number of LV-segments and high scar-burden in group-II as compared to group-I (figure-1). A total scar score value of >1.0 predicted failure with 100%-sensitivity and 75%-specificity. CMR revealed transmural-scar in the LBBP-Zone in all patients in group-II (n = 9; 100%). Transmural scar in LBBP-Zone by CMR had 100%-sensitivity and 100%-specificity for predicting the procedural-failure.
CMR helps in predicting the procedural failure of LBBP in patients with scarred LV. Presence of transmural-LGE in the LBBP-Zone predicts failure with high sensitivity and specificity.
植入部位存在瘢痕被认为是决定左束支起搏（LBBP）成功与否的主要因素。我们旨在分析经心脏磁共振成像（CMR）证实的左心室（LV）瘢痕患者手术失败的预测因素。
这是一项回顾性、观察性单中心研究，纳入了连续的心肌病患者，这些患者经CMR晚期钆增强（LGE）证实存在LV瘢痕且需要进行LBBP。手术失败定义为无法穿透间隔到达LV心内膜下。结果：共有25例心肌病患者在CMR中显示LGE，并被纳入研究。16例患者LBBP成功（I组；急性手术成功率64%）。其余9例患者（II组）电极无法穿透，因此进行了双心室起搏。I组患者在平均11.2±3.7个月的随访期间，LBBP导致QRS时限缩短和LV射血分数改善。LBBP后计算机断层血管造影显示成功的电极植入部位（LBBP区）为短轴视图下前间隔下方面和下间隔上方面的重叠区域（节段2/3；AHA模型）（图1C）。与I组相比，CMR显示II组LV节段的LGE数量明显更多，瘢痕负荷更高（图1）。总瘢痕评分值>1.0预测失败的敏感性为100%，特异性为75%。CMR显示II组所有患者（n = 9；100%）的LBBP区存在透壁瘢痕。CMR显示LBBP区的透壁瘢痕预测手术失败的敏感性和特异性均为100%。
CMR有助于预测LV瘢痕患者LBBP的手术失败。LBBP区存在透壁LGE预测失败具有高敏感性和特异性。
