St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.
St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada Canadian Heart Research Centre, Toronto, Ontario, Canada.
Heart. 2014 Sep 15;100(18):1456-61. doi: 10.1136/heartjnl-2014-305708. Epub 2014 May 19.
We aimed to study the relationships between left anterior hemiblock (LAHB) and the patient characteristics, management, and clinical outcomes in the setting of acute coronary syndromes (ACS).
Admission ECGs of patients enrolled in the Global Registry of Acute Coronary Events (GRACE) ECG substudy, and the Canadian ACS Registry I, were analysed independently at a blinded core laboratory. Multivariable logistic regression analysis was performed to assess the independent associations between LAHB on the admission ECG and in-hospital and 6-month mortality.
Of the 11 820 eligible ACS patients, 692 (5.9%) patients had LAHB. The presence of LAHB on admission was associated with older age, male sex, prior myocardial infarction, prior heart failure, worse Killip class, higher creatinine level, and higher GRACE risk score (all p<0.01). Patients with LAHB less frequently underwent cardiac catheterisation, coronary revascularisation or reperfusion therapy (all p<0.05). The LAHB group had higher in-hospital (6.9% vs 3.9%, p<0.001) and 6-month mortality (12.5% vs 7.7%, p<0.001). However, after adjusting for the known predictors of mortality in the GRACE risk models, LAHB was not independently associated with in-hospital death (OR 1.07, 95% CI 0.76 to 1.52, p=0.70), or death at 6 months (OR 1.00, 95% CI 0.75 to 1.34, p=0.99).
Across the broad spectrum of ACS, LAHB was associated with significant comorbidities, high-risk clinical features on presentation, and worse unadjusted outcomes. However, LAHB was not an independent predictor of in-hospital and 6-month mortality and did not carry incremental prognostic value beyond the known prognosticators in the GRACE risk models.
本研究旨在探讨急性冠状动脉综合征（ACS）患者左前分支阻滞（LAHB）与患者特征、处理方法和临床结局之间的关系。
在全球急性冠状动脉事件注册（GRACE）心电图子研究和加拿大 ACS 登记 I 中，对入选患者的入院心电图进行独立分析，并在一个盲法核心实验室进行分析。采用多变量逻辑回归分析评估入院心电图上 LAHB 与住院期间和 6 个月死亡率之间的独立相关性。
在 11820 例符合条件的 ACS 患者中，有 692（5.9%）例患者存在 LAHB。入院时存在 LAHB 与年龄较大、男性、既往心肌梗死、既往心力衰竭、较高的 Killip 分级、较高的肌酐水平和较高的 GRACE 风险评分相关（均 p<0.01）。LAHB 患者较少接受心脏导管检查、冠状动脉血运重建或再灌注治疗（均 p<0.05）。LAHB 组住院期间（6.9% vs 3.9%，p<0.001）和 6 个月死亡率（12.5% vs 7.7%，p<0.001）较高。然而，在校正 GRACE 风险模型中已知的死亡率预测因素后，LAHB 与住院期间死亡（OR 1.07，95%CI 0.76 至 1.52，p=0.70）或 6 个月死亡（OR 1.00，95%CI 0.75 至 1.34，p=0.99）无关。
在 ACS 的广泛范围内，LAHB 与明显的合并症、就诊时的高危临床特征以及较差的未经调整结局相关。然而，LAHB 不是住院期间和 6 个月死亡率的独立预测因子，并且在 GRACE 风险模型中的已知预后因素之外，LAHB 没有额外的预后价值。
