PubMed1997
To analyze the pulsatile movement of coronary arterial walls, intravascular ultrasound was used to measure the diameter changes in the arterial lumen of 32 patients with coronary artery disease (CAD group) and five patients with chest pain but no CAD (control group). Measurements were performed on segments of the proximal left anterior descending coronary artery that were angiographically nonstenotic. Following identification of the peak systolic and end-diastolic phases using intra-coronary pressure tracings, the luminal diameters were measured around the center at 4 degrees intervals using a computer-assisted image analyzer. The pulsatile diameter change (dD) and end-diastolic diameter (DD) at each interval were analyzed and compared between the CAD and control groups. Mean DD did not differ significantly between the CAD group (4.53 +/- 0.69 mm) and the control group (4.52 +/- 0.51 mm). In contrast, the mean dD in the CAD group (0.05 +/- 0.18 mm) was significantly lower than that of the control group (0.13 +/- 0.12 mm). The mean maximum and minimum standardized percentage pulsatile diameter changes were -10.6 +/- 6.2% and 16.2 +/- 5.9%, respectively, in the CAD group, and -2.7 +/- 4.6% and 11.7 +/- 1.3%, respectively, in the control group. The mean standard deviation of dD was significantly greater in the CAD group (0.182 +/- 0.05 mm) than in the control group (0.116 +/- 0.04 mm), which indicated dD in CAD patients varied to a greater degree than in control patients. The ratio dD/dP (dP : pulse pressure) was used as an index of vascular compliance at the site of measurement. The mean dD/dP was significantly smaller in the CAD group (1.1 +/- 2.5 x 10(-3) mm/mmHg) than in the control group (4.0 +/- 3.3 x 10(-3) mm/mmHg). Aniso-diametric wall movement in the coronary artery (as indicated by a negative dD during systolic expansion) was enhanced in the CAD group compared to the control group. This was probably caused by the early stages of the arterial sclerotic process as it progressed heterogeneously along the vessel wall. Thus, aniso-diametric movement, which is a functional abnormality of the coronary arterial wall, appears to antedate detectable morphological changes.