["Peripheral infarction blocks". Vectocardiographic analysis and electrogenetic hypothesis (author's transl)]

500 vectorcardiograms of variously located myocardial infarctions were analysed. Abnormalities of the afferent limb of QRS loop, consistent with intraventricular conduction disturbances, were detected in 42 cases. This pattern, according to Rosenbaum, was called "infarction block"; it was always associated with inferior and/or posterior infarction. This kind of block is shown by a large downward, righward and backward-directed vector, which always appears about 50 msec after the onset of ventricular activation. Total ventricular depolarization time was not significantly prolonged. The pattern was explained as a variant of "peri-infarction block" and its origin is hypothesized as the interruption of a peripheral ramification of LBB posterior fascicle.