ORIGINAL ARTICLES  VASCULAR SECTION 

The Journal of Cardiovascular Surgery 2002 April;43(2):223-30

Copyright © 2009 EDIZIONI MINERVA MEDICA

lingua: Inglese

Spectral and profile analysis of Doppler recording following below-knee arterial distal bypasses

Abraham P., Eudo M., Picquet J. *, Saumet J. L., Vielle B. **, Enon B. *

From the Department of Vascular Investigations *Vascular Surgery and **Medical Biostatics CHU, Angers, France

Background. Arterial ­below ­knee dis­tal bypass­es ­are asso­ciat­ed ­with a ­high ­risk of throm­bo­sis as com­pared to prox­i­mal bypass­es. We ­assumed ­that ­before ­the ­bypass ­occludes, in ­the ear­ly ­postsur­gi­cal peri­od, mea­sur­able veloc­ity chang­es, ­and/or ­the pres­ence of ­high inten­sity tran­sient sig­nals (­HITS) ­would ­occur.
Methods. Settings: institutional ref­er­ence cen­ter, hospitalized ­patients. Subjects: satisfactory Dop­pler record­ing ­was ­obtained in 51 ­among 61 con­sec­u­tive ­patients (32 ­males, 19 ­females, ­height: 165±7cm, ­weight: 68±12 kg) suf­fer­ing low­er extrem­ity arte­ri­al dis­ease, that under­went saph­e­nous (n=33), pros­thet­ic (n=4) or sequen­tial (n=14) ­below ­knee bypass­es. We per­formed a spec­tral ­and pro­file anal­y­sis of a sin­gle ­postsur­gi­cal 2 ­hour Doppler record­ing at ­the ­ankle lev­el ­and ana­lyzed Doppler ­derived indi­ces ­and clin­i­cal ­risk fac­tors in ­the eval­u­a­tion of ­the ­risk of ­bypass occlu­sion with­in 7 ­days fol­low­ing sur­gery.
Results. Primary paten­cy at ­day 7 ­was ­observed in 41 of ­the 51 oper­at­ed ­patients. The pres­ence of ­HITS ­was ­found in ~30% of ­the ­patients ­and pro­vid­ed no infor­ma­tion on ­the ­risk of throm­bo­sis. No clin­i­cal var­i­able ­was sig­nif­i­cant­ly asso­ciat­ed ­with an ­increased ­risk of throm­bo­sis. Whatever ­the dura­tion of record­ing, ­the pres­ence of a dia­stol­ic for­ward ­flow ­and ­wide sys­tol­ic veloc­ity chang­es ­were ­poor indi­ca­tors of ­bypass throm­bo­sis ­risk. On 512 ­beat record­ings, a ­mean sys­tol­ic veloc­ity ­below 1630 Hz ­and a stan­dard devi­a­tion of ­the resis­tance ­index >0.095 ­were asso­ciat­ed ­with a 6.74 [1.6-28.4] (p<0.01) ­and 14.5 [3.6-58.9] (p<0.001) ­times increas­es in ­the ­risk of ­bypass occlu­sion respec­tive­ly, com­pared ­with sub­jects ­that do ­not ful­fill ­each cri­te­ria.
Conclusions. Periods of tran­sient asymp­to­mat­ic no-­flow-­reflow ­events ­may be ­observed ­before ­the ­bypass irre­ver­sibly ­occludes. Prolonged Doppler record­ing ­should be pre­ferred to ­short ­term anal­y­ses, to ­allow ­for ­the detec­tion of ­these tran­sient ­events ­and ­may pro­vide poten­tial indi­ces ­for ­future ­research.