Evaluation of the Early Stage of Carotid Atherosclerosis Using the Vascular Response to Nitroglycerin and High-Resolution Ultrasonography

Abstract

therosclerosis is a series of histopathological changes that includes intimal thickening, degenerative compositional changes of the medial layer (sclerotic change) and atheroma-formation (atherotic change). 1 The recent development of high-resolution Bmode ultrasonography has made it possible to detect and evaluate the atheromatous changes of the arteries, particulary the carotid artery. [2][3][4][5] However, despite these studies, methods that evaluate the sclerotic change of an artery, an early stage of atherosclerosis, have not been established. Vascular sclerotic changes increase vascular stiffness, and may disturb the vascular responses to a vascular relaxant. Although decreased elasticity of the arterial wall in the atherosclerotic carotid artery has been reported, 6-9 the carotid artery response to vascular relaxant has not been reported yet.Nitroglycerin (NTG), a relaxant of vascular smooth muscle, may change arterial elasticity. 10,11 If the change in elasticity of the atherosclerotic artery in response to NTG is different from that of the normal artery, evaluation of this response may be valuable in assessing atherosclerotic changes. The purpose of the present study was to determine whether the early atherosclerotic changes of the common carotid artery (CCA) could be evaluated by the response of vascular elasticity to NTG, where there was no ultrasonic atheromatous plaque. The vascular elasticity was expressed by vascular strain (VS) and pressure-strain elastic modulus (Ep). Moreover, the extent of atherosclerosis of the CCA has been shown to be strongly correlated with the extent of coronary artery disease (CAD). 12-16 Therefore, we also examined whether the decreased elasticity response of the CCA to NTG was associated with CAD. Methods Study SubjectsThe study was performed in 52 patients who were admitted for the evaluation of CAD (35 men and 17 women, aged from 45 to 74 years old ), and 9 normal male volunteers (aged from 23 to 27 years old) without risk factors for atherosclerosis such as hyperlipidemia, hypertension, glucose intolerance and smoking. Patients with frequent arrhythmias, congestive heart failure, congenital and acquired heart disease were excluded, because the hemodynamic abnormality of these diseases may affect the diameter change of the CCA. Patients with recent cerebrovascular attacks and a blood pressure difference between the bilateral brachial artery of greater than 10 mmHg were also excluded. Informed consent was obtained from every Evaluation of the Early Stage of Carotid Atherosclerosis Using the Vascular Response to Nitroglycerin and High-Resolution UltrasonographyJpn Circ J 1998; 62: 494 -498 Cha-Po Lai, MD; Samon Koyanagi, MD**; Cheng-Kuang Shaw, DDS*; Akira Takeshita, MD**The purpose of this study was to determine whether the early stages of arterial atherosclerosis could be evaluated by the vascular response to nitroglycerin (NTG). The vascular elasticity of the common carotid artery (CCA) was evaluated at sites without atheromatous plaque using high-resolution ultr...

WISE 2005: responses of women to sublingual nitroglycerin before and after 56 days of 6° head-down bed rest

“…The pre-HDBR responses to NG were consistent with previous research with an increase in heart rate (7), reduction in cardiac stroke volume (39), and lower arterial systolic, mean, and pulse pressure (22,38,39). A novel observation was the almost 50% reduction in femoral blood flow that reflected a marked reduction in downstream vascular conductance as demonstrated by the large reverse (negative) component, shown in Fig.…”

Headache response to glyceryl trinitrate in patients with and without obstructive coronary artery disease

“…They concluded that the prevalence of carotid atheromatous plaque was highly correlated with that of CAD and that carotid vascular elasticity to GTN use was decreased in patients with severe CAD. 7 Their observation may support our theory that GTN causes less frequent headache in patients with atherosclerosis caused by impaired cerebral arterial dilatation. Adams et al 8 reported similar findings in 800 patients at risk for atherosclerosis.…”

Association Between Plasma Homocysteine Concentration and Carotid Atherosclerosis in Hemodialysis Patients

“…We chose the carotid maximum IMT as a measurement device for evaluating 168 patients on long-term dialysis because of this method's proven efficacy as a predictor of generalized atherosclerosis. [10][11][12] Results from those prior investigations positively correlated carotid maximum IMT with age, and Dempsey et al calculated that age accounted for 17.7% of variation in carotid plaque thickness. 15 Kawagishi et al reported that in uremic patients the carotid maximum IMT related with age and that the rate of thickening was faster than in nonuremic controls.…”

“…8 Since the development of ultrasonography, accurate measurement of arterial intimal-medial thickness (IMT) has become feasible, 9 and IMT of the extracranial carotid arteries evaluated by Bmode ultrasonography is now used as a marker of systemic and coronary atherosclerosis. 10,11 This noninvasive, repeatable procedure makes it possible to measure atherosclerosis directly and quantitatively in a large asymptomatic population. B-mode ultrasound, therefore, is suitable for studying the relationship of multiple risk factors to arterial disease.…”