Specificity for each of the 46 criteria of the Selvester QRS score for electrocardiographic myocardial scar sizing in left bundle branch block

•We investigated the specificity of the 46 criteria of the Selvester QRS score for left bundle branch block (abbreviated LB-SS) in a population with no scar, verified by CMR-LGE.•Several of the 46 LB-SS criteria were nonspecific.•We recommend against the LB-SS's clinical use until the score has been updated.

BackgroundThe Selvester QRS score consists of a set of electrocardiographic criteria designed to identify, quantify and localize scar in the left ventricle using the morphology of the QRS complex. These criteria were updated in 2009 to expand their use to patients with underlying conduction abnormalities, but these versions have thus far only been validated in small and carefully selected populations.AimTo determine the specificity for each of the criteria of the left bundle branch block (LBBB) modified Selvester QRS Score (LB-SS) in a population with strict LBBB and no myocardial scar as verified by cardiovascular magnetic resonance imaging with late gadolinium enhancement (CMR-LGE).MethodsWe identified ninety-nine patients with LBBB without scar on CMR-LGE, who underwent a clinically indicated CMR scan at three different centers. The ECG recording date was any time prior to or < 30 days after the CMR scan. The LB-SS was applied and specificity for detection of scar in each of the 46 separate criteria was determined.ResultsThe specificity ranged between 41% and 100% for the 46 criteria of LB-SS and 27/46 (59%) met ≥ 95% specificity. The mean ± SD specificity was 90% ± 14%.ConclusionSeveral of the criteria in the LB-SS lack adequate specificity. Elimination or modification of these nonspecific QRS morphology criteria may improve the specificity of the overall LB-SS.