On quantifying plaque size and intima-media thickness in carotid and femoral arteries. Comments on results from a prospective ultrasound study in patients with familial hypercholesterolemia

The aim of the present analysis in an ongoing observational study was to evaluate the possibility of measuring plaque size in ultrasound images from carotid and femoral arteries and the usefulness of quantitative plaque measurements in such a prospective study. Twenty-five patients with carotid plaques were identified in a group of patients with familial hypercholesterolemia (n = 50) compared with 7 subjects in a low-risk control group (n = 47). Only 20 of the 32 recorded plaques were accessible for quantitative follow-up measurements of area, base length, and thickness, which represents only 21% of all subjects investigated. In contrast, paired observations of intima-media thickness in the common carotid artery were available in 98% and in the carotid bulb in 87% of the subjects investigated. In those with paired observations of plaque area available, the data indicated a close relationship between the 2-year change recorded in plaque area and the 2-year change in intima-media thickness measured in a 10-mm-long predefined section of the carotid bulb (r = .81, P < .001, n = 19). The corresponding relationship between change in plaque area and change in a 10-mm-long section of the common carotid artery was r = .38 and P < .05 (n = 20). Quantitative measurements of plaques in the femoral arteries were also performed, but the results from these measurements were in most cases judged not to be useful. However, measurements of intima-media thickness in a 15-mm-long predefined section of the common femoral artery may be performed in a reproducible way in most patients. We conclude that the usefulness of plaque area measurements in prospective studies of the carotid artery seems limited because plaques available for quantitative measurements are present in only a small proportion of subjects. However, reproducible measurements of intima-media thickness in a predefined section of the carotid bulb are achievable in most subjects, and our data indicate that the changes recorded over time in the carotid bulb closely mirror changes occurring in the size of atherosclerotic plaques within the carotid artery region. In addition, present data indicate that measurements of intima-media thickness in the common carotid artery complement measurements performed in the carotid artery bulb in the study of early atherosclerosis.

Aortic stenosis in homozygous familial hypercholesterolaemia

Images

Noninvasive tracking of coronary atherosclerosis by electron beam computed tomography: rationale and design of the Felodipine Atherosclerosis Prevention Study (FAPS)

The Felodipine Atherosclerosis Prevention Study is designed to evaluate the efficacy of the calcium antagonist felodipine ER and combined felodipine/simvastatin therapy on retarding the progression of atherosclerosis, estimated by serial changes in coronary calcium evaluated by noninvasive electron beam computed tomography. Subjects include 180 men and women aged 40 to 69 and 50 to 69 years, respectively, with moderate type IIa dyslipidemia, with either cardiovascular disease or risk factors. All subjects receive simvastatin lipid-lowering therapy, and are randomized either to felodipine or placebo for a treatment period of 2 years. Monitoring of blood chemistry, measures of lipids and apolipoproteins, blood pressure, evaluation of symptoms, and interim clinical event monitoring are done at routine follow-up visits. Baseline and 2-year follow-up electron beam computed tomography, measuring changes in total calcium score, area, and mass, evaluate the effects of intervention on the progression of calcified atherosclerosis. The results from the Felodipine Atherosclerosis Prevention Study will provide valuable information about the effect of felodipine alone and in combination with simvastatin on progression of calcified atherosclerosis evaluated noninvasively.

Does the presence of the 3500 mutant apolipoprotein B-100 in low density lipoprotein particles affect their atherogenicity?

Apolipoprotein B-100 (apo B-100) is the protein component of low density lipoprotein (LDL) responsible for its binding and clearance by LDL receptors (LDL-R). In familial defective apo B-100 (FDB), a mutation in apo B-100 at residue 3500 markedly reduces its affinity for LDL-R, often causing accumulation of defective LDL particles, and an increased proneness to coronary artery disease (CAD). In FDB heterozygotes, about 70% of the LDL particles are mutant, which may alter their atherogenicity relative to LDL containing normal apo B. Therefore, we compared CAD in heterozygous FDB with CAD in heterozygous familial hypercholesterolemia (FH), since raised LDL is usually present from birth in both conditions, and in FH the LDL particles that accumulate have normal apo B, as the inherited defect involves the LDL-R. The clinical presentation of coronary atherosclerosis and its angiographic appearance were examined in FDB and FH patients matched for conventional cardiac risk factors (hypertension, smoking, sex) and serum lipid levels. There was no significant difference between the FDB and FH patients (n=11 pairs) in the type of cardiac symptoms or their ages of onset (50 +/- 9 vs. 45 +/- 11 years). Coronary angiographic appearance was also similar in both groups (n=9 pairs). These observations suggest that LDL particles with the 3500 mutation in apo B have the same atherogenicity as LDL particles with normal apo B.

Intima-media thickness after cholesterol lowering in familial hypercholesterolemia. A three-year ultrasound study of common carotid and femoral arteries

Patients with familial hypercholesterolemia (FH) (n = 53) were examined with B-mode ultrasound before and after 3 years of cholesterol-lowering therapy with pravastatin, cholestyramine, or a combination. The aim was to measure the progression rate of intima-media thickening during follow-up in the common carotid and common femoral arteries. Since for ethical reasons it was not possible to perform a randomized placebo controlled study in patients with FH, we chose to recruit an untreated control group with lower risk, matched for sex, age, height and weight, and with serum cholesterol below 6.5 mmol/l. At baseline, intima-media thickness was larger in the hypercholesterolemic group than in the control group in both the common carotid and common femoral arteries. The difference between the change over 3 years observed in the control group and the change observed in the hypercholesterolemic group was calculated and defined as 'net difference'. There was a -32% net difference in low density lipoprotein (LDL) in the hypercholesterolemic group during follow-up. The ultrasound investigation showed a concomitant net difference of -0.06 mm in mean carotid intima-media thickness (95% confidence interval, -0.11 to -0.01 mm) and of -0.09 mm in maximum carotid intima-media thickness (P < 0.05, 95% confidence interval, -0.16 to -0.01 mm), with no net change in lumen diameter. No decrease was recorded in common femoral intima-medial thickness. Seventeen of the patients with FH had a positive history of myocardial infarction (MI) and this subgroup had a significantly larger decrease in mean carotid intima-media thickness during follow-up than the subgroup of patients with a negative history of MI (P < 0.01). In conclusion, the results showed a reduction in common carotid intima-media thickness after long-term cholesterol-lowering therapy in patients with FH. This finding may indicate a beneficial effect on atherosclerosis development in these patients.

Increased prevalence of coronary ectasia in heterozygous familial hypercholesterolemia

BACKGROUND

Although coronary atherosclerosis most commonly produces clinical effects as a result of stenosis, aneurysmal disease also occurs. We have found an increased prevalence of ectasia and aneurysmal disease in familial hypercholesterolemia (FH) suggesting a link between plasma lipoproteins and coronary aneurysms.

METHODS AND RESULTS

In 197 asymptomatic subjects with FH, we examined the prevalence of ectasia and its association with coronary risk factors. An ectatic segment was defined as one with a luminal diameter > 1.5 times that of the adjacent normal segment, excluding poststenotic dilation. Among subjects with FH, 15% had ectasia compared with 2.5% of an age- and sex-matched control group of 198 subjects without FH presenting for coronary angiography (P < .001). These control patients had significantly more severe coronary atherosclerosis than patients with FH. Ectasia was 3 times more common in men than women (P < .025). Neither age nor hypertension was predictive. Although in part reflecting the striking sex differential, ectasia was strongly associated with a lower HDL cholesterol level (P = .003), a higher LDL/HDL ratio (P = .003), and to a lesser extent, a higher LDL cholesterol level (P = .07). No association was found with plasma triglycerides or very low-density lipoprotein cholesterol levels. Among FH patients, ectasia was strongly associated with an overall index of occlusive atherosclerotic disease, based on quantitative angiography (P = .004). Intracoronary ultrasound interrogation of aneurysmal segments revealed circumferential intimal thickening.

CONCLUSIONS

Coronary ectasia is more prevalent in patients with FH than in other patients with coronary atherosclerosis and shows a strong inverse association with HDL cholesterol levels. This suggests that disordered lipoprotein metabolism in FH may predispose patients to aneurysmal coronary artery disease.

Atherosclerotic plaque evolution in the descending thoracic aorta in familial hypercholesterolemic patients. A transesophageal echo study

We explored the concept that transesophageal echocardiography can be used as a tool to detect, characterize, and study plaque morphology in the descending thoracic aorta. The pattern of atherosclerotic plaques in the descending thoracic aorta in familial hypercholesterolemic (FH) patients was evaluated. Additionally, evolution of plaque characteristics as a result of therapy was analyzed. In a randomized prospective protocol, eight FH patients (five men and three women, aged 23 to 65 years [mean +/- SD, 42 +/- 14 years]) receiving standard therapy (n = 3; baseline low-density lipoprotein [LDL] cholesterol, 222 +/- 71 mg/dL, mean +/- SD) or LDL apheresis (n = 5; baseline LDL cholesterol, 262 +/- 51 mg/dL) were studied. Baseline and follow-up (mean, 12 months) transesophageal echocardiographic studies were performed. Measurements obtained were atherosclerotic plaque area (PA), aortic wall area (WA), total arterial area (TAA), and plaque-to-wall area ratio (PWR). LDL cholesterol decreased in both groups. The greatest severity of plaque was detected at 30 to 35 cm from the incisors (approximately 15 to 20 cm from the aortic arch). The smallest plaques were present at the arch and more distal descending aorta. In the control group, TAA, PA, and PWR did not change significantly (P = NS versus baseline). In the LDL-apheresis group, TAA increased (P < .05 versus baseline), PA decreased in three of five patients (P = NS versus baseline), and PWR fell (P < .05 versus baseline).(ABSTRACT TRUNCATED AT 250 WORDS)

Sonography in the detection of achilles tendon xanthomata in children with familial hypercholesterolaemia

Patients with heterozygous familial hypercholesterolaemia (FH) are at high risk for the development of coronary artery disease. Achilles tendon xanthomata are often the first clinical manifestation of FH, but are seldom palpable earlier than during the third decade. Twenty-one FH children aged 3-18 years underwent high-frequency ultrasound examination of the achilles tendon. Hypoechoic infiltration of the normal tendon structure was demonstrated in 8 of 21 (38%) of the FH children. The findings were similar in boys and girls. Control subjects (n = 68) aged 1-25 years had no sonographically detectable tendon abnormalities. The thickness of the achilles tendon of the FH children was (mean +/- SD) 7.1 +/- 1.5 mm (range 5-10 mm). The respective values for the controls were 5.8 +/- 1.0 mm (3-7 mm. We conclude that ultrasound examination sensitively detects cholesterol accumulation in the achilles tendon of FH children before tendon xanthomata are clinically evident.

Premature carotid atherosclerosis: does it occur in both familial hypercholesterolemia and homocystinuria? Ultrasound assessment of arterial intima-media thickness and blood flow velocity

BACKGROUND AND PURPOSE

Homocystinuria due to cystathionine beta-synthase deficiency and familial hypercholesterolemia are inherited disorders of metabolism that are associated with premature development of cardiovascular disease. This study addresses the possibility that different patterns of carotid wall damage and cerebral blood flow hemodynamics are present in these two metabolic diseases.

METHODS

Twelve patients with homocystinuria due to cystathionine beta-synthase deficiency (mean age, 24 years), 10 patients with homozygous familial hypercholesterolemia (mean age, 26 years), and 11 healthy control subjects (mean age, 26 years) underwent a vascular examination by noninvasive methods. B-mode ultrasound imaging was used to obtain measurements of intima-media thickness of common carotid, bifurcation, and internal carotid arteries as an index of atherosclerosis. Cerebral blood flow velocity was estimated from vascular examination of the middle cerebral artery by transcranial Doppler. Systolic, diastolic, and mean velocities were measured. Pulsatility index, a possible indicator of vascular resistance in the cerebral circulation, was also calculated.

RESULTS

Mean maximum intima-media thickness was 1.4 mm in patients with familial hypercholesterolemia, 0.6 mm in patients with homocystinuria, and 0.6 mm in control subjects. The difference between hypercholesterolemic and homocystinuric patients or control subjects was statistically significant (P < .001). Diastolic blood flow velocities were significantly reduced in the middle cerebral arteries of hypercholesterolemic patients compared with homocystinuric patients or control subjects (P < .05), whereas systolic or mean velocities did not differ. The pulsatility index, a possible indicator of vascular resistance in the cerebral circulation, was significantly higher in hypercholesterolemic patients compared with homocystinuric patients or healthy control subjects (P < .01). A direct relation was demonstrated between pulsatility index of the middle cerebral artery and mean maximum intima-media thickness of carotid arteries on the same side (P < .001).

CONCLUSIONS

Familial hypercholesterolemia is responsible for diffuse and focal thickening of carotid arteries and possibly also for hyperlipidemic endothelial dysfunction extending to small resistance arteries and leading to a disturbed cerebral blood flow. Patients with homocystinuria due to homozygosis for cystathionine beta-synthase deficiency seldom have plaques in their carotid arteries. They are similar to healthy control subjects with regard to both intima-media thickness and blood flow velocity in the middle cerebral artery. Therefore, it is unlikely that typical atherosclerotic lesions precede thrombotic events in homocystinuria. However, it is possible that arterial dilatations caused by medial damage lead to thrombosis in homocystinuric patients.

Regional cerebral blood flow in familial hypercholesterolemia

BACKGROUND AND PURPOSE

Although epidemiologic investigations are trying to clarify the role of plasma lipid concentrations (primarily cholesterol and its subfractions) as risk factors for both ischemic and hemorrhagic stroke, little information is available regarding the effect of sustained hypercholesterolemia on cerebral perfusion.

METHODS

Regional cerebral blood flow (CBF) was measured by the 133Xe inhalation method in 25 heterozygous patients (four untreated) affected with familial hypercholesterolemia. In 15 patients regional CBF was repeated 20 minutes after intravenous administration of acetazolamide (10 mg/kg body wt) to evaluate cerebrovascular reactivity. Correlations among cerebral perfusion data, present or pretreatment plasma lipid concentrations, and certain other clinical features were assessed by ANOVA.

RESULTS

Both basal regional CBF and cerebrovascular reactivity were normal in the vast majority of patients compared with age- and sex-matched normal control subjects. CBF was significantly dependent on pretreatment low-density lipoprotein cholesterol (LDL-C) concentration (P = .005) and the presence of symptomatic ischemic heart disease (P = .015). CBF was only slightly dependent on age (P = .05) and was not dependent on either lipoprotein(a) or present LDL-C concentration. CBF did not differ between treated and untreated patients, and the perfusional increase induced by acetazolamide was not related to any other variable.

CONCLUSIONS

Cerebral perfusion and cerebrovascular reactivity were maintained within the normal range despite long-lasting, severe hypercholesterolemia, even if a somewhat lower CBF was found in those patients with the highest LDL-C pretreatment levels. These results are in accord with the epidemiologic data that implicate hypercholesterolemia as a minor risk factor, if a risk factor at all, for intracranial atherosclerosis and ischemic stroke.

Impairment of endothelium-dependent dilation is an early event in children with familial hypercholesterolemia and is related to the lipoprotein(a) level

Familial hypercholesterolemia is associated with premature atherosclerosis. Since endothelial dysfunction is an early event in atherogenesis, we used a noninvasive method to assess endothelial function in the systemic arteries of 30 children aged 7-17 yr (median 11) with familial hypercholesterolemia (2 homozygotes, 28 heterozygotes, total cholesterol 240-696 mg/dl) and 30 healthy age- and sex-matched controls. Using high resolution ultrasound, the diameter of the superficial femoral artery was measured at rest, in response to reactive hyperemia (with increased flow causing endothelium-dependent dilation), and after sublingual glyceryltrinitrate (causing endothelium-independent vasodilation). Flow-mediated dilation was present in the controls (7.5 +/- 0.7%) but was impaired or absent in the hypercholesterolemic children (1.2 +/- 0.4%, P < 0.0001). Total cholesterol was inversely correlated with flow-mediated dilation (r = -0.61, P < 0.0001). In the hypercholesterolemic children, flow-mediated dilation was inversely related to the lipoprotein(a) level (r = -0.61, P = 0.027) but not to other lipid fractions. Glyceryltrinitrate-induced dilation was present in all subjects but was lower in the hypercholesterolemia group (10.0 +/- 0.6% vs 12.4 +/- 0.8%, P = 0.023). Thus, impaired endothelium-dependent dilation is present in children with familial hypercholesterolemia as young as 7 yr of age and the degree of impairment is related to the lipoprotein(a) level.

Atherosclerotic changes in the femoral and carotid arteries in familial hypercholesterolemia. Ultrasonographic assessment of intima-media thickness and plaque occurrence

B-mode ultrasound is increasingly used in clinical research to study the atherosclerotic process in the carotid arteries. The present investigation evaluated the feasibility of measuring intima-media thickness in the common femoral artery and assessed whether such measurement might provide further information on the extent of the atherosclerotic process in patients with familial hypercholesterolemia. A further aim was to study the relationship between the intima-media thickness of the common carotid artery and the occurrence of plaque in the carotid and femoral arteries. The results showed an increased intima-media thickness in the far wall of the common femoral artery in patients with familial hypercholesterolemia compared with the control subjects (P < .01). The results also showed a clear relationship between the thickness of the intima-media complex in the common carotid artery and the prevalence of plaque in the carotid and femoral arteries. This may be interpreted as an indication that an increase in intima-media thickness in the common carotid artery at least partly expresses a generalized atherosclerotic process. The atherosclerotic changes appeared to be more advanced in the femoral artery compared with the carotid artery. In future studies, therefore, valuable information on different stages of atherosclerotic changes may be achieved by combining information from B-mode recordings from both the carotid and femoral arteries.

Sonography of the Achilles tendon in hypercholesterolaemia

OBJECTIVES

Tendon xanthomas cause thickening of the tendon and are an important sign in monogenic familial hypercholesterolaemia (FH). The aim of our study was to investigate the usefulness of achilles tendon sonography in detecting FH patients. Special attention was paid to structural abnormalities of the achilles tendon.

DESIGN

A clinical study with methodological testing.

SETTING

Patients suspected of having FH were sent to the out-patient Department of Medicine from other departments of Turku University Central Hospital and from primary care units. The patients were studied by high-frequency ultrasound before more exact typing of the lipid disorder. An additional study of normolipidaemic volunteers and a phantom study were also carried out.

SUBJECTS

Forty FH patients, 51 non-FH hypercholesterolaemia patients and 41 normolipidaemic volunteers were included in the study. MAIN OUTCOME OF MEASURES: The thickness of the tendon was measured and the tendon structure and its echogenicity were recorded.

RESULTS

Twenty-five out of 40 (63%) FH patients had distinctly thickened tendons (men more than 10 mm, women more than 9 mm). Thirty-six (90%) had a typical structural alteration of low or mixed echogenicity of the tendon. Three non-FH patients were found to have xanthomas on sonography.

CONCLUSIONS

We conclude that ultrasonography is a sensitive method of detecting xanthomas that reveals the altered tendon structure even in xanthomatous tendons of normal thickness.

Ultrasonography of the Achilles tendon in hypercholesterolemia

The ultrasonographic (US) appearance of Achilles tendon was examined in 34 patients with hypercholesterolemia (10 with familial (FH), and 24 with secondary hypercholesterolemia (SH)), and in 22 patients with normal tendons. US findings were compared with clinical, laboratory, and radiologic results. In patients with FH, typical xanthomas in the form of hyperechoic tendinal tumors were found in only 15% while various forms of inhomogeneity of tendon structure without xanthoma formation were found in 75%. The high rate of tendon inhomogeneity may be due to the concomitant occurrence of both xanthomas and degeneration of tendon fibers. Physical examination revealed abnormalities in 60% of these patients. At CT of the tendons, abnormalities were found in 65% of the FH patients and in 40%, abnormalities were shown by plain radiography. In SH, the results did not differ significantly from normal controls. In our opinion US should be used to prove or rule out Achilles tendon abnormalities in patients with FH for prophylaxis and treatment of tendinitis and tendon rupture.

Abdominal aortic aneurysms in familial hypercholesterolemia--case reports

Familial hypercholesterolemia (FH) is a genetic disease characterized by high serum cholesterol levels and premature coronary atherosclerosis. Hypercholesterolemia is one of the factors promoting the arteriosclerotic process and is a major cause of aortic aneurysm. Few data are available, however, about abdominal aortic aneurysms (AAAs) in patients with FH. In this study, the clinical and angiographic characteristics of AAAs found in patients with FH were investigated. Thirty-one cases (23 men, 8 women, aged fifty +/- fourteen years) were examined by coronary angiography, thoracic and abdominal aortography, and clinical data. Abdominal aortography detected abdominal aneurysms in 8 cases (26%), all of whom were men, including 4 cases (50%) that were complicated by diabetes mellitus. The abdominal aneurysm patients manifested severe coronary atherosclerosis, severe abdominal aortic irregularity, and higher blood pressure than the nonaneurysm FH patients. These findings suggest that AAAs are an important and prevalent feature in FH, especially in men with diabetes mellitus and high blood pressure.

[Involvement of the heart valves and great vessels in homozygote familial hypercholesterolemia]

Homozygous familial hypercholesterolaemia is characterized by cutaneous xanthoma development from infancy, precocious and accelerated atherosclerosis with clinical signs of ischemic heart disease and frequent involvement of left heart valves resulting in stenosis and/or incompetence. Two cases are described of this condition, both associated with aortic stenosis. In one case mitral incompetence and thromboembolic pulmonary hypertension were also found. The mitral valve is involved in the atherosclerotic process at the level of the cusps. These become thickened and stiff. Aortic stenosis is mainly due to atheromas infiltrating the Valsalva sinuses and the ascending aorta. Pulmonary hypertension, never reported before in this disease, is probably due to concomitant atheromatosis involving the pulmonary artery with secondary fatty embolism.

Impaired left ventricular relaxation and hyperinsulinemia in patients with primary hypercholesterolemia

Fifteen non-obese patients with familial hypercholesterolemia and fifteen normocholesterolemic subjects matched for age, body mass index, waist/hip ratio, arterial blood pressure and sedentary life style underwent blood sampling for determination of fasting plasma glucose, insulin, total-, LDL-, HDL-cholesterol, triglycerides, free fatty acids, apolipoprotein A1 and B. In both groups of subjects we determined erythrocyte membrane microviscosity and performed an echocardiographic study. We demonstrated that hypercholesterolemic patients had a significant increase in fasting plasma total cholesterol (8.9 +/- 0.5 vs. 5.5 +/- 0.3 mmol/l, P less than 0.001), insulin (79 +/- 4 vs. 58 +/- 4 pmol/l, P less than 0.05) and apolipoprotein B (2.2 +/- 0.5 vs. 1.3 +/- 0.5 g/l P less than 0.01). In the echocardiographic study we found a significant impairment in left ventricular relaxation (isovolumic relaxation time (IRT) 106 +/- 6 vs. 73 +/- 7 ms, P less than 0.01). Erythrocyte membrane microviscosity (0.253 +/- 0.004 vs. 0.225 +/- 0.003, P less than 0.05) was also increased in hypercholesterolemic patients. Finally we found that erythrocyte membrane microviscosity correlated with fasting plasma insulin levels (r = -0.46, P less than 0.03) and IRT (r = -0.52, P less than 0.01).

Arterial wall thickness in familial hypercholesterolemia. Ultrasound measurement of intima-media thickness in the common carotid artery

B-mode ultrasound was used to noninvasively determine wall thickness and lumen diameter in the common carotid artery in patients with familial hypercholesterolemia (n = 53) and in a control group (n = 53). The controls were matched for sex, age, height, and weight, and all had a serum cholesterol level below 6.5 mmol/l. The study was performed to evaluate whether the patients had a thicker arterial wall compared with that of the control group. Wall thickness was determined as the combined intima-media thickness of the far wall and is presented as the mean and maximum thickness of a 10-mm-long section of the common carotid artery. The difference between the groups was 0.13 mm in mean wall thickness (p less than 0.001; 95% confidence interval, 0.07-0.18 mm) and 0.20 mm in maximum wall thickness (p less than 0.001; 95% confidence interval, 0.09-0.23 mm). Fifty of the subjects were examined twice to estimate the interobserver variability. The coefficients of variation for mean and maximum wall thickness were 10.2% and 8.9%, respectively. The two study groups were well matched and differed only in lipid levels. Thus, there is reason to believe that the difference in wall thickness can be explained by the background of familial hypercholesterolemia and the increased cholesterol levels.

Effect of plasmapheresis on the liver uptake of ApoB-lipoproteins labeled with technetium-99m

To study liver low density lipoprotein (LDL)-receptor activity before and after plasmapheresis, [99mTc] very low density lipoprotein (VLDL) was used. Autologous VLDL was labeled, sterilized by filtration, and administered intravenously to patients under a gamma camera. The uptake of lipoproteins in the liver was measured by scintiscanning. Liver activity curves were generated for each patient. The liver activity in patients with the heterozygous form of familial hypercholesterolemia (FH) and in patients with symptomatic atherosclerosis (SA) without hereditary deficit of LDL receptors was reduced as compared to healthy people. Plasmapheresis enhanced the liver uptake of the 99mTc-labeled lipoproteins in atherosclerotic patients. Thus, labeled metabolites could presumably be of use in assessing the effect of plasmapheresis on liver function.

Prevalence of femoral atherosclerosis in asymptomatic men with hyperlipoproteinaemia

Sixty-two male subjects with primary hyperlipoproteinaemia of type IIA (n = 18), type IIB (n = 18) or type IV (n = 24) underwent femoral arteriography to investigate the degree of atherosclerosis. All except two were free from symptoms of peripheral arterial disease. The presence of atheroma was determined according to a standardized consensus procedure based on visual interpretation. Atherosclerosis were graded by means of a scoring system, whereby an overall atherosclerosis score (OAS) was calculated for each patient, based on four consecutive segments of the femoral artery. Thirteen type IIA (72%), 14 type IIB (78%) and 18 type IV (75%) patients had femoral atherosclerosis, and the mean OAS in the patients with hyperlipoproteinaemia of these types were 0.58, 0.75 and 0.49, respectively, all with a standard error of the mean about 0.05. The atherosclerosis score increased the more distal the arterial segment, being most prevalent in the lower inferior segment. The OAS was higher in patients of above median age, in those with systolic or diastolic blood pressure above the median and in smokers. Multiple stepwise regression analysis showed that low density lipoproteins cholesterol was highly significantly related to OAS among smokers. In conclusion, femoral atherosclerosis is a prevalent finding in asymptomatic subjects with hyperlipoproteinaemia and could serve as a basis for intervention studies.

Results of serial coronary angiography in patients with homozygous familial hypercholesterolaemia

We studied the progression of coronary angiographic findings in a series of 10 patients with homozygous familial hypercholesterolaemia. All patients had medical treatment; six had additional surgical treatment. They were followed over a period of 2-10 years (mean follow-up five years). Three types of evolution were observed: (a) normal coronary angiography with no development of any lesion over a period of eight years in two young patients; (b) regression of proximal coronary stenoses in three patients, and (c) progression of coronary angiographic status in five patients. A different evolution of proximal and distal segment lesions was observed; while more than two-thirds of proximal segments stenoses improved and no proximal lesion increased with a 45% decrease in plasma cholesterol level, no improvement was obtained at the distal level. Distal lesions tended to increase and new lesions appeared in spite of a major plasma cholesterol level reduction. When early treatment results in a cholesterol plasma level decrease of more than 45% and a level of about 4 g l-1 over a very long period of time, the coronary prognosis may be good.

Coronary angiographic characteristics in Japanese patients with heterozygous familial hypercholesterolemia

Coronary angiographic findings were analyzed in 51 consecutive patients (36 males and 15 females) with heterozygous familial hypercholesterolemia (FH) and 279 consecutive patients (216 males and 63 females) without FH (non-FH). The coronary stenosis index and over 75% stenosis vessel subset were almost three times as high in the FH group. The incidence of myocardial infarction was almost twice as high in the FH group. Levels of total cholesterol and its lipoprotein fractions, except HDL-cholesterol, were almost twice as high in the FH group. In the FH group aged under 50 years, the two parameters of coronary angiogram and the incidence of myocardial infarction were significantly higher in males than in females. However, in the group aged over 50 years, all three parameters were not significantly different between those in males and females. The level of HDL-cholesterol was significantly lower in males than in females. A significantly higher incidence (18%) of coronary ectasia was observed in the FH group compared with the incidence (2%) in non-FH. All patients with coronary ectasia were males, except one female with FH. On comparison of the males among the FH patients with those among the non-FH patients matched for total cholesterol, age and other risk factors, the FH patients were associated with a significantly higher degree of coronary atherosclerosis and lower level of HDL-cholesterol. Seven FH patients with a normal coronary angiogram were observed. However, any factors as regards age, total cholesterol, HDL-cholesterol and Achilles tendon thickness failed to distinguish between the FH patients with a normal coronary angiogram and those without.(ABSTRACT TRUNCATED AT 250 WORDS)

Vascular calcification in types II and IV hyperlipoproteinemia: radiographic appearance and clinical significance

Nearly 90% of patients with clear-cut hyperlipidemia seen in clinical practice have type II or IV hyperlipoproteinemia. Previous studies have shown that these syndromes have different distributions of coronary artery atherosclerosis and different outcomes after coronary bypass grafting. A characteristic pattern of vascular calcification on chest films might have some prognostic value. Therefore, to determine the location and extent of aortic root and coronary artery calcification seen on chest films, 33 consecutive patients with type II and 17 with type IV hyperlipoproteinemia were studied who were admitted for coronary arteriography between 1970 and 1982. Among the 33 patients with type II disease, 21 women and 12 men, 22 had radiographically visible calcification that was different in distribution from that usually found in atherosclerotic disease. The ascending aorta was involved in 21 and the arch in 12. In eight patients, the calcium outlined a distinctive narrowing of the ascending aorta. Six patients had significant left ventricular obstruction; in five it was from aortic valve stenosis. Of the 17 type IV patients, 16 men and one woman, none had aortic calcification or left ventricular outflow obstruction, and only one had coronary artery calcification. These data demonstrate that patients with type II hyperlipoproteinemia have severe calcific atherosclerosis of the aortic root that often is visible on chest films. Such calcification may alert physicians to the presence of type II hyperlipoproteinemia and the high probability of severe coronary artery disease.

Cross sectional echocardiographic assessment of the aortic root and coronary ostial stenosis in familial hypercholesterolaemia

Aortic root abnormalities (atherosclerotic thickening and obstruction) seen at necropsy may readily be detected by aortography in familial hypercholesterolaemia. We studied 35 patients with familial types IIa and IIb hyperlipoproteinaemia including three homozygotes and 32 heterozygotes. Two homozygotes showed abnormal bright echoes (atheroma) encircling the proximal aortic root, which interfered with full excursion of the aortic cusps. One homozygote showed the typical echocardiographic features of supravalvular aortic stenosis at the superior border of the sinus of Valsava with normal aortic cusps. Cardiac catheterisation showed valvular gradients of 15 and 80 mm Hg in two homozygotes and a supravalvular gradient of 40 mm Hg in the third. Left coronary artery ostial stenosis was identified by echocardiography in all three homozygotes. Echocardiographic measurements of the aortic root in the 32 heterozygotes were similar to the control group, but 10 patients showed abnormal bright echoes within the aortic cusps and four had supravalvular changes similar to, but less severe than, the homozygotes. In one severely heterozygote supravalvular atheroma prevented full aortic cusp excursion, and this finding was confirmed during coronary artery bypass surgery.

[Xerographic measure of Achilles tendon thickness in familial hypercholesterolemia]

The authors have applied a xeroradiographic method to the measurement of Achilles' tendon thickness in familial hypercholesterolemia. They have not found a significant increase of the thickness, unless patients with xanthomas were included. Statistical value of the method is thus contested.