Comments on the historical vignette in Vol. 134, No. 2

To evaluate the effect of isolated left bundle branch block (LBBB) on diastolic filling patterns, we evaluated 14 subjects with isolated LBBB and 16 age- and sex-matched healthy subjects with normal ventricular conduction by echocardiography. Maximum E-wave velocity, E/A ratio, deceleration time of E wave, and the slope of deceleration of the E wave were lower in subjects with LBBB compared with subjects with normal ventricular conduction. Doppler filling patterns were significantly altered in subjects with isolated LBBB.