Histopathologic analysis of 32 paired coronary arteries showed no significant differences in microcirculatory structural remodeling parameters downstream of noncritical stenoses compared to unobstructed arteries.
Observational (n=55)
Single-blind
No
Does coronary stenosis induce downstream microcirculatory structural remodeling in the human coronary circulation?
Histopathologic analysis of human myocardium demonstrates that the microcirculation distal to noncritical coronary stenoses does not undergo structural remodeling, contradicting previous experimental animal findings.
p-value: p=>0.05
OBJECTIVE: Inducible myocardial ischemia is influenced by contributions of both the epicardial artery and the coronary microcirculation. Experimental studies have found adverse microcirculatory remodeling to occur downstream of severe coronary stenoses. Coronary physiology studies in patients contradict the experimental findings, as the minimal microvascular resistance is not modified by stenoses. The objective was to determine whether microcirculatory remodeling occurs downstream of coronary stenoses in the human coronary circulation. Approach and Results: Myocardium corresponding to 115 coronary arteries of 55 deceased patients was investigated. Histopathologic staining of the microcirculation was performed using antibodies against SMA-α (smooth muscle actin-α) and CD31, to stain arterioles and capillaries, respectively. The following parameters were analyzed: ratio between lumen and vesel area, ratio between lumen and vessel diameter (both ratios for arterioles of <40, 40-100, and 100-200 µm diameter), arteriolar density, and capillary density. From the 55 patients, 32 pairs of an unobstructed coronary artery and a coronary artery with a stenosis were formed. No statistically significant differences between any of the microcirculatory parameters were found. A confirmatory unpaired analysis compared 3 groups: (1) coronary arteries in patients without coronary artery disease (n=53), (2) unobstructed coronary arteries in patients with a stenosis in one of the other coronary arteries (n=23), and (3) coronary stenoses (n=39). No statistically significant differences were observed between the groups. CONCLUSIONS: The microcirculation distal to noncritical stenoses does not undergo structural remodeling in the human coronary circulation.
Waard et al. (Thu,) conducted a observational in Coronary artery disease (n=55). Coronary artery stenosis vs. Unobstructed coronary artery was evaluated on Microcirculatory structural remodeling (lumen/vessel area ratio, capillary/arteriolar density) (p=>0.05). Histopathologic analysis of 32 paired coronary arteries showed no significant differences in microcirculatory structural remodeling parameters downstream of noncritical stenoses compared to unobstructed arteries.