title: Left atrial abnormality as an electrocardiographic criterion for the diagnosis of left ventricular hypertrophy in the presence of right bundle branch block.
abstract: Left atrial (LA) abnormality determined from precordial lead V1 was assessed by 2 observers as a criterion of left ventricular (LV) hypertrophy in the presence of right bundle branch block (BBB) in 23 patients. The presence of LV hypertrophy was confirmed from a postmortem cardiac partition technique and defined at 2 levels of confidence: probable and definite hypertrophy. Observers reliably differentiated between the hypertrophied and normal-sized ventricle in the presence of right BBB by using LA abnormality as an electrocardiographic criterion. When defined as definite hypertrophy, observer 1 correctly identified LV hypertrophy in 78% of the cases and observer 2 in 67% of the cases. False-positive results were present in 21% of cases by observer 1 and 14% by observer 2. Comparable results were achieved when a definition of probable hypertrophy was used. Observer performance of recognition of LA abnormality in this study was satisfactory with 91% agreement between observers. Our results are comparable and in some instances superior to conventional criteria commonly recommended to diagnose LV hypertrophy on the electrocardiogram without right BBB.
mesh_terms: D000368:Aged; D002037:Bundle-Branch Block / Q000150:complications / Q000175:diagnosis*; D006332:Cardiomegaly / Q000150:complications / Q000175:diagnosis*; D004562:Electrocardiography; D006325:Heart Atria / Q000002:abnormalities*; D006801:Humans; D008297:Male