BACKGROUND: Two distinct right coronary artery (RCA) morphologies have been previously described: sigma- and C-shaped RCAs. While the C-shaped RCA was significantly associated with atherosclerosis, the sigma-shaped was not. The association of RCA morphology and vascular endothelial function has not yet been assessed. METHODS: To evaluate the association between the RCA's morphology and flow-mediated endothelium-dependent dilation (FMD) in patients without evidence of atherosclerotic lesions, we prospectively assessed FMD in 49 consecutive patients with non-specific chest pain, who were referred to our laboratory 30+/-10 days after corroboration of normal coronary arteries on coronary angiography. Endothelium-dependent brachial artery FMD and endothelium-independent nitroglycerin-mediated vasodilation (NTG) were assessed using high resolution (15 MHz) linear array ultrasound. The patients were divided into 2 groups according to their RCA morphology on coronary angiograms (sigma and C) which were analyzed by 2 independent readers who were blinded to the patients' FMD results. RESULTS: The C-shaped group exhibited a significantly lower FMD compared to the sigma-shaped group (9.0+/-4.2% vs. 14.3+/-4.7%, p<0.04, respectively), while NTG was the same in both groups. There were no significant group differences in other variables. CONCLUSIONS: Endothelium-dependent FMD in the brachial artery is significantly greater in sigma- compared to C-shaped RCA in coronary arteries without overt atherosclerotic lesions, suggesting a potential mechanism whereby C-shaped RCA are predisposed to atherosclerosis.
BACKGROUND: Two distinct right coronary artery (RCA) morphologies have been previously described: sigma- and C-shaped RCAs. While the C-shaped RCA was significantly associated with atherosclerosis, the sigma-shaped was not. The association of RCA morphology and vascular endothelial function has not yet been assessed. METHODS: To evaluate the association between the RCA's morphology and flow-mediated endothelium-dependent dilation (FMD) in patients without evidence of atherosclerotic lesions, we prospectively assessed FMD in 49 consecutive patients with non-specific chest pain, who were referred to our laboratory 30+/-10 days after corroboration of normal coronary arteries on coronary angiography. Endothelium-dependent brachial artery FMD and endothelium-independent nitroglycerin-mediated vasodilation (NTG) were assessed using high resolution (15 MHz) linear array ultrasound. The patients were divided into 2 groups according to their RCA morphology on coronary angiograms (sigma and C) which were analyzed by 2 independent readers who were blinded to the patients' FMD results. RESULTS: The C-shaped group exhibited a significantly lower FMD compared to the sigma-shaped group (9.0+/-4.2% vs. 14.3+/-4.7%, p<0.04, respectively), while NTG was the same in both groups. There were no significant group differences in other variables. CONCLUSIONS: Endothelium-dependent FMD in the brachial artery is significantly greater in sigma- compared to C-shaped RCA in coronary arteries without overt atherosclerotic lesions, suggesting a potential mechanism whereby C-shaped RCA are predisposed to atherosclerosis.
Authors: In Hyun Jung; Jongkwon Seo; Gwang Sil Kim; Hye Young Lee; Young Sup Byun; Byung Ok Kim; Kun Joo Rhee; Sung-Jin Hong; Chul Kim Journal: Cardiovasc J Afr Date: 2021-06-08 Impact factor: 1.167