Increased carotid intima-media thickness in hypertensive patients is caused by increased medial thickness |
Hee-Kwan Won, Wuon-Shik Kim, Ki-Young Kim, Dae-Woo Hyun, Taek-Geun Kwon, Jang-Ho Bae |
Cardiology Division, Department of Internal Medicine, Yeungnam University Hospital1 |
원저 : 고혈압 환자의 경동맥 내중막 두께의 증가는 중막 두께의 증가에 기인한다 |
원희관.김원식.김기영.현대우.권택근.배장호, Wuon-Shik Kim, Ki-Young Kim, Dae-Woo Hyun, Taek-Geun Kwon, Jang-Ho Bae |
|
|
|
Abstract |
Backgrounds/Aims It has been suggested that there is a differential response of the vasculature to systemic risk factors for atherosclerosis. We sought to evaluate the impact of hypertension on the carotid arterial wall using new methods that can measure each arterial wall layer.
Methods The study subjects consisted of 163 patients who underwent carotid arterial scanning using high-resolution ultrasound that could measure the left carotid intima-media, intima, and media separately. The individual carotid arterial wall thickness was measured off-line by a new method using the Canny edge-detection algorithm.
Results Hypertensive patients (n=79, mean age 61.8 years) had a higher prevalence of diabetes (31.6% vs 11.9%, p=0.004) and a lower level of HDL-cholesterol than did normotensive patients (41.8±11.0 mg/dL vs 45.7±10.0 mg/dL, p=0.019). Hypertensive patients had higher carotid intima-media thickness (CIMT, 0.81±0.21 mm vs 0.74±0.18 mm, p=0.003) and carotid medial thickness (CMT, 0.46±0.12 mm vs 0.42±0.09 mm, p=0.007) than did normotensive patients, whereas carotid intimal thickness (CIT) was not significantly different (0.34±0.04 mm vs 0.34±0.04 mm, p=0.196). Multivariate analysis revealed that the independent factors of CIMT were CMT (β=0.915, p<0.001), hypertension (β= 0.076, p=0.008), age (β=0.074, p=0.010), and sex (β=-0.079, p=0.005). Pearson correlation coefficient between CIMT and CMT was higher (r=0.932, p<0.001 vs r=0.445, p<0.001) than that between CIMT and CIT. The correlation between CIMT and CMT was higher (r=0.940, p<0.001 vs r=0.910, p<0.001) in hypertensive patients than in normotensive patients, whereas that between CIMT and CIT was lower (r=0.344, p=0.002 vs r=0.583, p<0.001) in hypertensive patients.
Conclusions The increased CIMT is caused by increased CMT in hypertensive patients, and this finding is compatible with the medial hypertrophy seen in hypertension. The carotid medial layer should be the focus of attention in future studies looking at hypertensive patients. (Korean J Med 75:179-185, 2008)
Key Words: Hypertension; Tunica media; Carotid arteries |
Key Words:
Hypertension; Tunica media; Carotid arteries |
|