Oliveros R A, Seaworth J, Dlabal P W, Beckmann C H
Aviat Space Environ Med. 1980 Oct;51(10):1144-6.
The intraventricular conduction time was measured during rest, exercise, and recovery in five patients who developed acute left anterior hemiblock during exercise-induced myocardial ischemia. The A QRS shifted from 58 +/- 17 degrees at rest to -66 +/- 11 degrees during exercise (p less than 0.001). The intraventricular conduction time at rest was 86 +/- 4 ms and increased to only 90 +/- 4 ms during left anterior hemiblock. Our observations suggest that the intraventricular conduction time is not always prolonged during left anterior hemiblock, particularly if this conduction abnormality is acute.
