Active vascular contraction significantly reduced the outer diameters of the coronary intima-media layer compared to the passive state (3.17 vs 3.62 mm at 1.2 axial stretch; P < 0.05).
A two-layer mechanical model of the coronary artery reveals that the intima-media layer bears the majority of circumferential tension and that the adventitia layer significantly influences vascular contraction.
Absolute Event Rate: 3.17% vs 3.62%
p-value: p=< 0.05
Since vascular tone is regulated by smooth muscle cells in the media layer, a multilayer mechanical model is required for blood vessels. Here, we performed biaxial mechanical tests in the intima-media layer of right coronary artery to determine the passive and active properties in conjunction with the passive properties of adventitia for a full vessel wall model. A two-layer (intima-media and adventitia) model was developed to determine the transmural stress and stretch across the vessel wall. The mean ± SE values of the outer diameters of intima-media layers at transmural pressure of 60 mmHg in active state were 3.17 ± 0.16 and 3.07 ± 0.18 mm at axial stretch ratio of 1.2 and 1.3, respectively, which were significantly smaller than those in passive state (i.e., 3.62 ± 0.19 and 3.49 ± 0.22 mm, respectively, P 25%) in the intima-media layer compared with those in the intact vessel. This suggests that the adventitia layer affects vascular contraction. The two-layer analysis showed that the intima-media layer bears the majority of circumferential tensions, in contrast to the adventitia layer, while contraction results in decreased stress and stretch in both layers.
Huo et al. (Fri,) reported a other. Active state (vascular contraction) vs. Passive state was evaluated on Outer diameters of intima-media layers at transmural pressure of 60 mmHg and axial stretch ratio of 1.2 (p=< 0.05). Active vascular contraction significantly reduced the outer diameters of the coronary intima-media layer compared to the passive state (3.17 vs 3.62 mm at 1.2 axial stretch; P < 0.05).