An Experimental Study of the Production and Time Course of Poststenotic Dilatation in the Femoral and Carotid Arteries of Adult Dogs
Three degrees of stenosis were produced in the femoral and carotid arteries of twenty-six adult dogs. Minimum stenosis caused neither proximal nor distal dilatation. Moderate stenosis, defined by the presence of a distal thrill and bruit, always produced post-stenotic dilatation. Severe stenosis, with a marked decrease or absence of distal. pulsation caused temporary proximal dilatation.
The arteries were painted with a radi-opaque paste which did not change their elastic properties and allowed daily measurements of arterial diameter. Radiograms showed that if turbulence was present, the artery usually started to dilate within twenty-four hours, reached a steady state within ten days, and then remained essentially unchanged for up to ten months. The dilatation was fusiform, and usually extended for 1.75 to 2.0 cm distal to the end of the band.
Frequency analysis of the murmurs showed a wide frequency spectrum with no resonant points and no components over 1500 cycles/ sec. This type of sound is more likely to be produced by turbulence than by cavitation or vortex formation.
Dye injection in a model showed a random dye distribution starting a short distance distal to the constriction.
Analysis of pressure-volume diagrams from these arteries35 suggested that the dilatation was due to a weakness of the arterial wall in the poststenotic segment.
- Received July 1, 1963.
- © 1963 American Heart Association, Inc.