The management of diagonal branch (D) occlusion is still controversary. The association between the flow loss of D and the prognosis remains unclear. We aim to detect the impact of D flow on cardiac function and clinical outcomes in patients with anterior ST-segment elevation myocardial infarction (STEMI). Patients with anterior STEMI undergoing primary percutaneous coronary intervention (PCI) at our clinic between October 2015 and October 2018were reviewed. Anterior STEMI due to left anterior descending artery (LAD) occlusion with or without loss of the main D flow (TIMI grade 0–1 or 2–3) was enrolled in the analysis. The short- and long-term incidence of major adverse cardiac events (MACEs, a composite of all-cause death, target vessel revascularization and reinfarction) and left ventricular ejection fraction (LVEF) were analyzed. A total of 392 patients (mean age of 63.9 years) with anterior STEMI treated with primary PCI was enrolled in the study. They were divided into two groups, loss (TIMI grade 0–1, n = 69) and no loss (TIMI grade2–3, n = 323) of D flow, before primary PCI. Compared with the group without loss of D flow, the group with loss of D flow showed a lower LVEF post PCI (41.0% vs. 48.8%, p = 0.003). Meanwhile, loss of D flow resulted in the higher in-hospital, one-month, and 18-month incidence of MACEs, especially in all-cause mortality (all p < 0.05). Landmark analysis further indicated that the significant differences in 18-month outcomes between the two groups mainly resulted from the differences during the hospitalization. In addition, multivariate Cox proportional hazards analysis found that D flow loss before primary PCI was independent factor predicting short- and long-term outcomes in patients with anterior STEMI. Loss of the main D flow in anterior STEMI patients was independently associated with the higher in-hospital incidences of MACEs and all-cause death as well as the lower LVEF.

中文翻译：

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ST抬高型心肌梗死患者的对角分支和预后。

对角分支（D）咬合的治疗仍存在争议。D的流量损失与预后之间的关系仍不清楚。我们旨在检测D流量对前ST段抬高型心肌梗死（STEMI）患者心功能和临床结局的影响。我们回顾了2015年10月至2018年10月在我们诊所接受原发性经皮冠状动脉介入治疗（PCI）的前STEMI患者。该研究纳入了因左前降支（LAD）闭塞而导致或不伴有主要D流量减少（TIMI等级0-1或2-3）的前部STEMI。分析了主要不良心脏事件（MACE，全因死亡，目标血管血运重建和再梗塞的综合因素）和左心室射血分数（LVEF）的短期和长期发生率。该研究共纳入了392例（平均年龄为63.9岁）前路STEMI接受原发性PCI治疗的患者。在初次PCI之前，他们分为两组，D流的损失（TIMI等级0–1，n = 69）和无损失（TIMI等级2–3，n = 323）。与没有D流丢失的组相比，有D流丢失的组在PCI后LVEF降低（41.0％vs. 48.8％，p = 0.003）。同时，D流量的丢失导致住院，1月和18个月MACE发生率升高，尤其是全因死亡率（所有p <0.05）。地标分析进一步表明，两组之间18个月结局的显着差异主要是由于住院期间的差异所致。此外，多元Cox比例风险分析发现，原发性PCI前的D流量损失是预测STEMI前期患者短期和长期预后的独立因素。前STEMI患者的主要D流量减少与院内MACE发生率较高，全因死亡以及LVEF较低独立相关。