Analysis of femoral artery intima-media thickness during the cardiac cycle

BackgroundVariations in the intima-media thickness (IMT) of the carotid artery during the cardiac cycle are well established. The change in femoral IMT during the cardiac cycle is largely unknown. This study focuses on the variation of femoral IMT, vessel diameter, and cross-sectional area (CSA) of the IMT during the cardiac cycle.MethodsVideo clips of the femoral artery were obtained using B-mode ultrasonography in 60 patients between the ages of 18 and 50. IMT and diameter measurements were made using automated software, and CSA was subsequently calculated. Triplicate measurements of each femoral artery were made at three points in the cardiac cycle: the R wave, the T wave, and at the point of maximal vessel diameter falling after the T wave and before the following P wave.ResultsFemoral IMT, diameter, and CSA did not show a statistically significant difference with measurement on the R versus the T wave (P > 0.36, P > 0.28, and P > 0.76, respectively). Interestingly, when comparing measurements on the R or T wave with measurements taken at the maximum vessel diameter, there was a statistically significant difference in vessel diameter (P < 0.001) and CSA (P < 0.005) but not in femoral IMT (P > 0.2).ConclusionsUnlike studies of the carotid artery, there were no statistically significant differences between measurements made at the R versus the T wave. There were, however, statistically significant differences noted in diameter and CSA when measurements were taken at a point later in the cardiac cycle. This has ramifications for future studies on vascular remodeling.