Effects of Upright Posture on Atrioventricular Accessory Pathway Conduction Michael J. Reiter, MD, PhD, and David E. Mann, MD

The ektrophysidogk effects of 45” head-up tilt were studied in 19 patknts with atrioventficular acceuory pathways. Upright posture enhanced both anterograde and retragrade m pathwaycendMknwhencemparedtothesupinepositionz the anterograde bkdc cyde length decreaeed from374f52ms(meanfstandarderrer)(wpine) to 303 f 33 ms (tilt) (p