Aortic stiffness in young patients with heterozygous familial hypercholesterolemia.
ABSTRACT Dyslipidemia is a primary risk factor for the development of atherosclerosis. Aortic distensibility is an important determinant of left ventricular function and coronary blood flow whose possible alterations in patients with dyslipidemia have not been fully investigated.
To assess the effect of dyslipidemia on the elastic properties of the aorta, we studied 60 patients (mean age 37+/-11 years) with heterozygous familial hypercholesterolemia and no manifest arterial disease and compared them with 20 of their normolipidemic siblings (mean age 34+/-10 years). Two indexes of the aortic elastic properties were measured: aortic distensibility was calculated by use of the formula: 2 x (AoS-AoD)/PP x AoD, and aortic stiffness index was calculated by use of the formula: In (SBP/DBP)/(AoS-AoD)/AoD, where AoS and AoD are aortic root end-systolic and end-diastolic diameters, respectively, SBP and DBP are systolic and diastolic arterial pressure, respectively, and PP is pulse pressure. Internal aortic root diameters were measured at 3 cm above the aortic valve by use of two-dimensional guided M-mode transthoracic echocardiography, and arterial pressure was measured simultaneously at the brachial artery by sphygmomanometry.
The mean aortic systolic and diastolic diameter index did not differ significantly between the two groups. In contrast, aortic distensibility was found to be significantly reduced in subjects with isolated familial hypercholesterolemia compared with that in the control group (2.15+/-1.72 cm2.dynes(-1).10(-6) vs 3.18+/-1.58 cm2.dynes(-1).10(-6), p < 0.02). In addition, the mean aortic stiffness index was double in patients with familial hypercholesterolemia compared with that in normolipidemic subjects.
Severe dyslipidemia does not overtly influence aortic dimensions but leads to impairment of aortic elastic properties before the occurrence of clinical manifestations of atherosclerotic disease.
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ABSTRACT: To evaluate the impact of risk factors on atherosclerotic changes of aortic wall and valve in patients with and without non-familial hypercholesterolemia by transthoracic echocardiography. One hundred and eleven patients with non-familial hypercholesterolemia and 112 control subjects were included in the study. Aortic wall and valve were evaluated by visual assessment of wall hyperechogenicity and measuring the valve thickness. Aortic diameters were obtained at the levels of annulus, sinus of Valsalva and at the supravalvular level in the parasternal long-axis view by M-Mode echocardiographic examination. The relationship between parameters of aortic atherosclerosis and risk factors was studied by multivariate logistic regression analysis, Pearson and Spearman correlation analyses. The prevalence of aortic wall hyperechogenicity was found to be higher in patients with hypercholesterolemia (84.7% vs 70.5%, p=0.01). The mean aortic root diameters at all levels of patients with hypercholesterolemia were found to be significantly smaller than in patients of the control group (3.1+/-0.3 mm vs 3.2+/-0.5 mm, p=0.02 for annulus level, 3.4+/-0.4 mm vs 3.5+/-0.4, p=0.004 mm for the level of sinus of Valsalva and 3.2+/-0.3 mm vs 3.4+/-0.5 mm, p<0.001 - supravalvular level), but no difference was noted regarding the aortic velocity and pressure gradient across the aortic valve. Multivariate stepwise logistic regression analysis showed that age (OR=1.1, CI - 1.02-1.09, p=0.002) and smoking (OR=2.2, CI - 1.06-4.58, p=0.04) were independent predictors of aortic valve thickness. Hypercholesterolemia was an independent predictor for aortic wall hyperechogenicity (OR=2.5, CI - 1.3-4.9, p=0.009) but not for valve thickness. Age, smoking and hypercholesterolemia are related to atherosclerotic involvement of aortic wall and valve.Anadolu kardiyoloji dergisi: AKD = the Anatolian journal of cardiology 03/2007; 7(1):2-5. · 0.44 Impact Factor
Article: Morphological and morphometric studies of the aorta, pulmonary trunk, and heart of streptozotocin-induced diabetic Wistar rats.[show abstract] [hide abstract]
ABSTRACT: Micro-anatomical changes in the aorta, pulmonary trunk, and left ventricle of Wistar rats were studied after the administration of streptozotocin. Twenty adult Rattus norvegicus were randomly assigned into two groups (control and diabetic) of ten rats each. Diabetes mellitus was experimentally induced in the diabetic group of rats by daily intra-peritoneal administration of multiple doses of 40 mg/kg streptozotocin dissolved in 0.1 M sodium citrate buffer for five consecutive days. The control group was given the equivalent volume of citrate buffer. The animals were monitored for four weeks after streptozotocin administration. Post sacrifice, the left ventricle, aorta, and pulmonary trunk were excised, weighed, and fixed by immersion in 10% formol saline. The tissues were processed for paraffin embedding, and sections of 6 mum thickness were produced and stained with H & E for general histological observations, and Verhoeff-van Gieson elastic fibre stain to demonstrate elastic fibres in these cardiovascular structures. The data obtained were analyzed with descriptive and inferential statistics. Histopathological and morphometric examinations of the stained sections showed a significant increase in the thickness of the tunica intima of aorta (t = -7.49; df = 9; p < 0.05) and pulmonary trunk (t = -10.81; df = 9; p < 0.05) in diabetic rats (14.59 + or - 1.189 mm and 11.307 + or - 0.863 mm, respectively) when compared to that of the control group (3.62 + or - 0.353 mm and 3.22 + or - 0.244 mm, respectively). In addition, the distribution of elastic and collagen fibres was sparse in the hearts of the diabetic group when compared to that of the control group. The findings of this study demonstrated that diabetes mellitus might cause some alterations in the microanatomy of cardiovascular structures.Folia morphologica 11/2009; 68(4):207-14. · 0.52 Impact Factor
Article: Aortic stiffness as a risk factor for recurrent acute coronary events in patients with ischaemic heart disease.[show abstract] [hide abstract]
ABSTRACT: Aortic elasticity is an important determinant of left ventricular performance and coronary blood flow. Moreover, it has been shown that aortic elastic properties deteriorate in patients with coronary artery disease. However, the predictive role of aortic elasticity in the occurrence of coronary events, has not been addressed so far. Therefore, we set out to test prospectively the hypothesis that invasive as well as non-invasive measures of aortic elastic properties, assessed at rest from pressure-diameter relationships, could predict the development of recurrent coronary events. Clinical variables and measures of aortic function were assessed in 54 normotensive patients with coronary artery disease. The aortic pressure-diameter relationship was derived invasively with a high-fidelity Y shaped catheter (developed in our Institution) for aortic diameter measurements, simultaneously with a Millar catheter for aortic pressure measurements. Aortic root distensibility was assessed by non-invasive techniques. During an average of 3 years follow-up, 12 of 54 patients either developed unstable angina (n=8) or acute myocardial infarction (n=4). By multivariate Cox model analysis, aortic stiffness was the strongest predictor of progression to any end-point (relative risk: 3.24, CI: 1.79 to 5.83;P=0.000). When aortic stiffness was not considered, aortic distensibility was the only independent predictor for acute coronary syndromes (relative risk: 0.37 CI: 0.21 to 0.65;P=0.000). In patients with coronary artery disease, aortic elastic properties are powerful and independent risk factors for recurrent acute coronary events.European Heart Journal 04/2000; 21(5):390-6. · 10.48 Impact Factor