Evaluation of electrocardiographic criteria for predicting left ventricular hypertrophy and dilation in presence of left bundle branch block.

Background: The utility of standard published electrocardiographic (ECG) criteria for left ventricular hypertrophy (LVH) in patients with left bundle branch block (LBBB) is not established. We have previously shown that in ECGs demonstrating LBBB, QRS duration outperforms vectorcardiographic X, Y, Z lead and root-mean-squared (3D) amplitudes and voltage-time-integrals in diagnosing LVH and dilation. We sought to evaluate diagnostic yields of published LVH criteria versus QRS duration for ECG based diagnosis of LVH and dilation in presence of LBBB.

Methods: We included adult patients with typical LBBB having ECG and transthoracic echocardiogram performed within 3 months of each other in 2010-2020. We obtained area under receiver-operator characteristic curve (AUC) for QRS duration and each of the published ECG LVH criteria to predict increased LV mass indexed (↑LVMi, women >95 g/m, men >115 g/m) and LV end diastolic volume indexed (↑LVEDVi, women >61 mL/m, men >74 mL/m).

Results: Among 413 adults (53 % women, age 73 ± 12 yr) with LBBB, the traditional LVH criteria performed poorly to detect ↑LVMi or ↑LVEDVi. Cornell voltage-duration product had the highest AUCs (↑LVMi 0.634, ↑LVEDVi 0.580). QRS duration had a higher AUC for diagnosing ↑LVMi (women 0.657, men 0.703) and ↑LVEDVi (women 0.668, men 0.699) compared to any other criteria.

Conclusions: In patients with LBBB, prolonged QRS duration (women ≥150 ms, men ≥160 ms) is a superior predictor of LVH and dilation than traditional ECG-based LVH criteria.