Effect of blood pressure on prevalence of carotid atheroma.

Abstract

SUMMARYIn an attempt to elucidate the mechanism by which hypertension acts as a risk factor for major non-haemorrhagic stroke, its effect on the prevalence of carotid atheroma has been studied angiographically. The carotid angiograms of 269 patients with cerebral tumours have been reviewed for evidence of coincidental atheromatous change. The prevalence of signs of arterial disease at the carotid bifurcation proved to be greater amongst patients with an elevated casual blood pressure reading, though the effect was small and confined to subjects over 50 years of age.It is argued that other factors must contribute to the connection between hypertension and the risks of cerebral infarction.Stroke Vol 14, No 4, 1983 CEREBROVASCULAR ACCIDENTS in hypertensive subjects may be due to cerebral hemorrhage or infarction. Cerebral hemorrhage is almost always associated with elevated arterial blood pressure except in those with primary haemotological disorders.' It is believed to be due to rupture of Charcot Bouchard aneurysms which are only common in hypertensive individuals 2 and match in distribution the sites of major hemorrhage. 3Cerebral infarction is also more common in hypertensive subjects.3 -4 The prospective data from the Framingham Survey show that hypertension is the most important risk factor for the development of "atherothrombotic brain infarction" (by which was meant stroke with no blood-staining of the cerebrospinal fluid).5 This is partly due to small deep lacunar infarcts occurring in hypertensive subjects as a consequence of lipohyalinosis of small perforating arteries exposed to chronically elevated blood pressure.6 However, large infarcts, as encountered in most non-haemorrhagic strokes are also associated with hypertension 4 and this has traditionally been attributed to an increase in the prevalence or severity of atheroma in the presence of high blood pressure.We have investigated this hypothesis by examining the carotid bifurcation on angiograms not performed for cerebrovascular disease but for cerebral tumour to find whether evidence of vessel wall disease is related to the patient's blood pressure. MethodsPatients undergoing angiography for investigation of cerebral tumour at the National Hospitals Queen Square and Maida Vale, and at The Middlesex Hospital were considered. The prevailing blood pressure on admission was extracted from the case notes and therefore represents a single "casual" reading. The mean arterial blood pressure was also calculated. The patients' sex and age were also noted.The angiograms were reviewed by one or both authors and the neck films studied. A decision was taken as to whether they showed any evidence of irregularity of the vessel wall likely to represent the effect of ather- omatous change. The blood pressure levels were unknown at the time of the reading of the angiograms. ResultsThe angiograms from 269 patients were studied (174 males; 95 females). Fifty-eight showed changes indicating atheromatous disease at the carotid bifurcation (34 males; 24 females).Mean v...

Serum Cholesterol Level Is Associated with the Severity of Carotid Stenosis in Symptomatic Patients: Results from NASCET

“…Previous studies relating plasma lipoprotein concentrations in patients with symptomatic carotid bifurSeverity of carotid stenosis cation disease showed inconsistent results [1][2][3][4][5][6][7][8][9][10][11]. Our study in elderly symptomatic patients supports the notion of cholesterol in the pathogenesis of carotid atherosclerosis.…”

“…In the literature, relationships between the traditional risk fac tors for stroke and the extent of carotid stenosis have remained uncertain [1][2][3][4][5][6][7][8][19][20][21], Although hypertension is a well-established risk factor for stroke, its role in the presence or severity of carotid stenosis has been contro versial. The Italian Multicenter Trial [3,4,21] found that hypertension correlated to the severity of carotid stenosis in symptomatic patients.…”

“…However, its relationship to plasma cholesterol level is still a subject of dispute [1][2][3][4][5][6][7][8][9][10][11]. Different study populations and different methods of measuring carotid stenosis (e.g.…”

Noninvasive study of arterial hypertension and carotid atherosclerosis.

“…However, little is known about the prevalence of atherosclerotic lesions at the carotid bifurcation in hypertensive individuals. The only available data have been obtained from selected subgroups of patients studied by angiography 4 or necropsy.…”