Rate-dependent variation in the duration of the QRS complex with left anterior fascicular block.
- D M Mirvis,
- J P Bandura, and
- D A Brody
Abstract
The case of a 67-year-old man with combined ischemic and valvular heart disease is presented. Electrocardiographic abnormalities included left anterior fascicular block with a variable duration of the QRS complex. The width of the QRS complex was dependent on the length of the cycle, being broader with short than with long preceding R-R intervals. This is interpreted as a tachycardia-dependent focal block coexisting with a fixed delay in fascicular conduction.
