Cardiology department, Maastricht University Medical Center, Maastricht, the Netherlands.
Methodology and Statistics, CAPHRI, Maastricht University, Maastricht, the Netherlands.
Int J Cardiol. 2019 Jul 1;286:61-65. doi: 10.1016/j.ijcard.2019.01.051. Epub 2019 Jan 15.
Left bundle branch block (LBBB) morphology is associated with improved outcome of cardiac resynchronisation therapy (CRT) and is an important criterion for patient selection. There are, however, multiple definitions for LBBB. Moreover, applying these definitions seems subjective. We investigated the inter- and intraobserver agreement in the determination of LBBB using available definitions, and clinicians' judgement of LBBB.
Observers were provided with 12‑lead ECGs of 100 randomly selected CRT patients. Four observers judged the ECGs based on different LBBB-definitions (ESC, AHA/ACC/HRS, MADIT, and Strauss). Additionally, four implanting cardiologists scored the same 100 ECGs based on their clinical judgement. Observer agreement was summarized through the proportion of agreement (P) and kappa coefficient (k).
Relative intra-observer agreement using different LBBB definitions, and within clinical judgement was moderate (range k 0.47-0.74 and k = 0.76 (0.14), respectively). The inter-observer agreement between observers using LBBB definitions as well as between clinical observers was minimal to weak (range k 0.19-0.44 and k = 0.35 (0.20), respectively). The probability of classifying an ECG as LBBB by available definitions varied considerably (range 0.20-0.76). The agreement between different definitions of LBBB ranged from good (P = 0.95 (0.07)) to weak (P = 0.40 (0.22)). Furthermore, correlation between the different LBBB definitions and clinical judgement was poor (range phi 0.30-0.55).
Significant variation in the probability of classifying LBBB is present in using different definitions and clinical judgement. Considerable intra- and inter-observer variability adds to this variation. Interdefinition agreement varies significantly and correlation of clinical judgement with LBBB classification by definitions is modest at best.
左束支传导阻滞（LBBB）形态与心脏再同步治疗（CRT）的疗效改善相关，是患者选择的重要标准。然而，LBBB 有多种定义。此外，应用这些定义似乎具有主观性。我们研究了使用现有定义和临床医生对 LBBB 的判断来确定 LBBB 的观察者间和观察者内一致性。
为 100 名随机选择的 CRT 患者的 12 导联心电图提供了 12 名观察者。四名观察者根据不同的 LBBB 定义（ESC、AHA/ACC/HRS、MADIT 和 Strauss）对 ECG 进行判断。此外，四名植入心脏病专家根据他们的临床判断对相同的 100 个 ECG 进行评分。观察者间的一致性通过一致性比例（P）和kappa 系数（k）来总结。
不同 LBBB 定义和临床判断的相对观察者内一致性为中度（范围 k 0.47-0.74 和 k=0.76（0.14））。观察者之间使用 LBBB 定义以及临床观察者之间的观察者间一致性为最小到弱（范围 k 0.19-0.44 和 k=0.35（0.20））。可用定义对 ECG 进行 LBBB 分类的概率差异很大（范围 0.20-0.76）。不同 LBBB 定义之间的一致性从良好（P=0.95（0.07））到弱（P=0.40（0.22））不等。此外，不同 LBBB 定义与临床判断之间的相关性较差（范围 phi 0.30-0.55）。
使用不同的定义和临床判断，对 LBBB 进行分类的概率存在显著差异。相当大的观察者内和观察者间变异性增加了这种变异性。定义之间的一致性差异显著，临床判断与 LBBB 分类的相关性充其量只是适度的。
