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Biomedical subjects

C Pitsavos

Publications and source records attributed to C Pitsavos.

At least 37 records · Page 2Linked to original sources
PubMed2000

Absence of any significant effects of circadian blood pressure variations on carotid artery elastic properties in essential hypertensive subjects.

We sought in this study to examine the effects of diurnal blood pressure variations upon common carotid artery (CCA) elasticity in selected subjects with uncomplicated moderate essential hypertension. Towards this end, 174 non-smoker subjects with stage I-II essential hypertension and without diabetes mellitus, left ventricular hypertrophy and carotid atherosclerosis, were classified as dippers and non-dippers according to the diurnal variation of >10% between mean daytime and night-time systolic and diastolic blood pressure (BP) in 24-h non-invasive ambulatory BP monitoring. CCA distensibility was derived by a combination of surface ultrasonographic data and simultaneous BP measurements at the brachial artery. The dippers and non-dippers were similar with respect to demographic characteristics. Non-dippers had significantly greater office systolic BP, 24-h systolic BP and ambulatory pulse pressure (PP) and significantly less (daytime-night-time) systolic and diastolic BP fall (by 16 mm Hg and 11 mm Hg respectively, P< 0.0001) compared to dippers. CCA distensibility was significantly reduced in non-dippers compared to dippers (by 0.89 dyne(-1)/cm(2/)10(-6), P < 0.05). Multiple linear regression analysis identified patient age and ambulatory PP as significant predictors of the CCA elasticity index. When patient age, 24-h systolic and diastolic BP were used as covariates in an analysis of covariance, the difference of CCA elasticity between dippers and non-dippers ceased to reach statistical significance. In contrast, when patient age, ambulatory PP, systolic (daytime-night-time) BP fall and diastolic (daytime-night-time) BP fall were used as covariates, the difference of CCA distensibility between dippers and non-dippers continued to be statistically significant. In conclusion, the excessive impairment of CCA elastic properties in non-dippers compared to dippers hypertensive seems to be ascribed to the increased of total 24-h haemodynamic load and not to the circadian pattern of BP. Journal of Human Hypertension (2000) 14, 813-818

Adult↗
PubMed2000

Contraception in women at high risk or with established cardiovascular disease.

Oral contraceptives are one of the most effective and widely used reversible contraceptive methods. Over 90 million women worldwide, including over 44 million in developing countries, are now using oral contraceptives. Despite their advantages, there is concern about the links between combined oral contraceptives and the risk of cardiovascular disease. The risk attributable to oral contraceptive use in women < 35 years of age is small, even if they smoke, but there are substantially increased risks in older women who both smoke and use oral contraceptives. Differences between oral contraceptive types in the relative risk of venous thromboembolism contribute little to the total cardiovascular mortality associated with oral contraceptive use, even though the total number of cardiovascular events is increased. It is important to consider the user's age and smoking status when determining oral contraceptive-attributable risks. Hormonal oral contraceptives have changed and now contain lower doses of estrogen and progestagen.

Adult↗
PubMed2000

Relevance of adenosine deaminase and lysozyme measurements in the diagnosis of tuberculous pericarditis.

OBJECTIVE: To assess the value of pericardial fluid adenosine deaminase (ADA) and pericardial lysozyme (Lys) as tools in diagnosing tuberculous pericarditis. METHODS: Forty-one patients (age range 17--77 years) with significant pericardial effusion were included in the study. Diagnostic pericardiocentesis and pericardial biopsy were performed while serum and pericardial fluid ADA and Lys were measured in all patients. Grouping of patients resulted as follows: group I = 7 patients with tuberculous pericarditis; group II = patients with neoplastic pericarditis; group III = 30 patients with idiopathic pericarditis. RESULTS: Pairwise multiple comparison procedures revealed a significant difference of ADA in group I versus group III (p < 0.05) but not versus group II. Furthermore, pericardial Lys in group I was higher than in groups II and III (p < 0.05). A strong correlation between pericardial ADA and Lys was found (r = 0.733, p = 0.01) for all the patients. Receiver operating curves showed a value of 72 U/l as cutoff point of pericardium ADA, with a sensitivity of 100% and a specificity of 94% in the diagnosis of tuberculous pericarditis. Similarly for pericardial Lys, a value of 6.5 microg/dl had a sensitivity and specificity of 100 and 91.17%, respectively. CONCLUSIONS: Both measurements of pericardial ADA and Lys need to be taken into account when attempting the early diagnosis of tuberculous pericarditis.

Adenosine Deaminase↗
PubMed1999

Relation of ambulatory blood pressure load with left ventricular geometry in untreated patients with mild-to-moderate hypertension.

Whether ambulatory blood pressure (ABP) load is associated with left ventricular (LV) geometry was assessed in 335 patients (range 32-72 years) with stage I-II essential hypertension by performing 24-h ABP monitoring and echocardiographic examination. Of these 335 hypertensive subjects, 116 (34.5%) had normal LV geometry, 136 (40.5%) had concentric LV remodelling, 37 (11%) had eccentric LV hypertrophy and 46 (14%) had concentric LV hypertrophy according to the relative wall thickness and left ventricular mass index. Subjects with concentric LV hypertrophy had significantly increased 24-h systolic BP (SBP), diastolic BP (DBP) and mean arterial pressure as well as increased 24-h SBP and DBP load compared to those with normal LV geometry or concentric LV remodelling while there was no difference in the above parameters in comparison with the subjects with eccentric LV hypertrophy. The incidence of patients with normal LV geometry was significantly decreasing and the incidence of patients with LV-CH was significantly increasing as the degree of ABP loads were increasing. Using multiple regression analysis models with each type of LV geometry as a dependent variable and various degree of ABP loads as independent variables, it was revealed that normal LV geometry was significantly related with normal values of 24-h SBP and DBP load (P < 0.05) while there was not any significant relation between concentric LV remodelling and 24-h SBP or DBP load values. Concentric LV hypertrophy was significantly related with increased values of both 24-h SBP and DBP load (P < 0.05) while eccentric LV hypertrophy was significantly related with increased values of 24-h DBP load only (P < 0.05). In conclusion normal LV geometry is associated with normal values of SBP and DBP load while concentric LV hypertrophy is associated with increased values of both SBP and DBP load.

Adult↗
PubMed1999

Fixed subaortic stenosis revisited. congenital abnormalities in 72 new cases and review of the literature.

Seventy-two patients aged 2-65 years (mean 20.2) with fixed subaortic stenosis (FSS) are reported. All patients underwent echocardiography and angiography prior to surgical intervention. Sixty-four (89%) had discrete subaortic stenosis (DSS) and 8 (11%) tunnel type stenosis (TSS). Patients with DSS aged 2-65 years (mean 29) while patients with TSS aged 10-34 years (mean 19) and had a distinct female preponderance (7:1). Twenty-five patients (39%) with DSS had other congenital abnormalities of which aortic stenosis associated with bicuspid aortic valve was slightly more common than ventricular septal defect (7:6). Five patients with TSS had a small aortic annulus and hypoplastic aorta. Our data and those in the literature indicate that TSS although related to DSS has certain features that may set it apart as a distinct entity. In addition DSS appears to be associated with aortic stenosis and bicuspid aortic valve as frequently as with ventricular septal defect.

Adolescent↗
PubMed1998

Effects of postural changes on left atrial function in patients with hypertrophic cardiomyopathy.

BACKGROUND: We assessed left atrial function in normal subjects and in patients with hypertrophic cardiomyopathy (HCM) by using Doppler echocardiography at the supine position and after sudden standing. METHODS AND RESULTS: Twenty-seven patients with hypertrophic obstructive cardiomyopathy (HOCM), 17 patients with HCM, and 35 normal subjects were studied. From the transmitral Doppler flow velocities, peak early and late (E and A) waves, E/A ratio, and time velocity integrals (Ei and Ai) were calculated. Left atrial active contribution (LAAC) was assessed as the ratio Ei/(Ei + Ai). Furthermore, isovolumetric relaxation time (IVRT) was estimated by means of Doppler echocardiography. In the supine position, the E/A ratio was similar in the 3 groups. Conversely, LAAC was significantly higher in patients with HOCM (24.4 +/- 2.0) and in patients with HCM (23.3 +/- 3.3) compared with normal subjects (20.3 +/- 2.3, P <.001 and P <.05, respectively). After sudden standing, LAAC increased significantly in normal subjects by 11%, in patients with HOCM by 24%, and in patients with HCM by 13% (P <.001). Similarly, IVRT increased significantly in all study groups (P <. 001). By using stepwise forward multiple linear regression analysis, we found that LAAC was associated with age, IVRT, and body mass index in the supine position and with diastolic blood pressure and IVRT in the standing position. CONCLUSIONS: Left atrial contribution to left ventricular filling was increased after sudden changes of posture in normal subjects and in patients with HOCM or HCM.

Adult↗
PubMed1998

Aortic stiffness in young patients with heterozygous familial hypercholesterolemia.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Adult↗
PubMed1998

Effects of ventricular pacing-induced tachycardia on aortic mechanics in man.

OBJECTIVE: Effects of pacing-induced tachycardia on left ventricular function have been studied extensively. However, little attention has been focused on aortic elastic properties during heart rate increments. The aim was to determine the effects of right ventricular pacing on the aortic elastic properties. METHODS: We studied 14 normal subjects (baseline blood pressure, 129/84 +/- 10/6 mmHg; aortic diameter, 23.5/21.3 +/- 2.4/1.9 mm) at rest, during rapid right ventricular pacing (at five stepwise heart rate increases of 20 bpm every 2 min) and after 5 min recovery. Shifts as well as changes in the slope and the stiffness constant of the pressure diameter (p-d) relation, derived from simultaneous tip-micromanometer aortic pressure recordings and high-fidelity ultrasonic intravascular aortic diameter recordings, were used as indices of aortic stiffness. Wave reflection was also studied. RESULTS: Aortic pulse pressure and strain significantly decreased after pacing-induced tachycardia (p < 0.0001 and < 0.05, respectively). During pacing, the slope of the linear p-d relation as well as the stiffness constant were decreased, followed by increases at recovery (p < 0.0001). The augmentation index and the aortoventricular coupling ratio were significantly decreased (p < 0.0001). CONCLUSIONS: Pacing-induced increases in pulse frequency may result in improved aortic distensibility and aortoventricular coupling.

Aorta↗
PubMed1998

Assessment of left atrial pressure-area relation in humans by means of retrograde left atrial catheterization and echocardiographic automatic boundary detection: effects of dobutamine.

OBJECTIVES: This study sought to validate and apply a new method for obtaining the left atrial (LA) pressure-area relation. BACKGROUND: In physiologic investigations, the pressure-area relation is the most accurate and representative index of LA hemodynamic status. METHODS: We applied real-time two-dimensional echocardiographic imaging with automatic boundary detection to estimate LA area changes. To obtain LA pressure, a catheter-tipped micromanometer was introduced retrogradely into the left atrium using a steerable cardiac catheter developed at our institution. Twenty-five patients (11 normal subjects, 7 patients with an enlarged left atrium due to heart failure, 7 patients with atrial fibrillation) were studied before and after dobutamine administration. From the LA pressure-area relation, the area of the A loop (the first counterclockwise loop) and the V loop (the second clockwise loop), the pressure-minimal area relation and the LA passive elastic chamber stiffness constant were measured. RESULTS: Normalized pressure-minimal area relation was highly linear and sensitive to changes in inotropic state (normal subjects: from 0.96 to 1.27 mm Hg/cm2, p < 0.01; patients with heart failure: from 0.59 to 0.68 mm Hg/cm2, p = NS; patients with atrial fibrillation: from 0.80 to 1.06 mm Hg/cm2, p < 0.05). The LA stroke work index was accurately calculated, and a very good correlation was found with LA preload. LA stroke work index was lower in patients with heart failure (3.9 +/- 0.8 cm2 x mm Hg, p < 0.001), whereas the LA stiffness constant was increased in patients with heart failure (0.801 +/- 0.097 cm(-2), p < 0.01) and atrial fibrillation (0.796 +/- 0.091 cm(-2), p < 0.01) compared with normal subjects (stroke work index 7.3 +/- 1.9 cm2 x mm Hg, stiffness constant 0.623 +/- 0.107 cm(-2), respectively). In addition, increased inotropic state after dobutamine administration resulted in improved LA pump function (stroke work index) in normal subjects (from 10.2 +/- 0.9 to 13.8 +/- 1.9 cm2 x mm Hg, p < 0.001) and patients with heart failure (from 4.3 +/- 0.4 to 7.6 +/- 0.4 cm2 x mm Hg, p < 0.001), as well as in decreased stiffness constant in all groups of patients (normal subjects: from 0.712 +/- 0.141 to 0.473 +/- 0.089 cm(-2); patients with heart failure: from 0.896 +/- 0.181 to 0.494 +/- 0.093 cm(-2); patients with atrial fibrillation: from 0.779 +/- 0.145 to 0.467 +/- 0.086 cm(-2), p < 0.001). CONCLUSIONS: The method described here is both safe and reproducible for obtaining the LA pressure-area relation. LA function is impaired in patients with heart failure and in those with atrial fibrillation and may be acutely improved with inotropic agents in both normal and diseased atria.

Adrenergic beta-Agonists↗
PubMed1998

Effects of balloon mitral valvuloplasty on left atrial function in mitral stenosis as assessed by pressure-area relation.

OBJECTIVES: This study sought to investigate the changes induced on the pressure-area relation of the left atrium in patients with mitral stenosis after percutaneous balloon mitral valvuloplasty. BACKGROUND: Left atrial (LA) function is influenced by changes in LA afterload. The latter is increased in mitral stenosis as a result of increased resistance to blood flow imposed by the stenotic mitral valve. METHODS: We studied the effects of acute alterations of LA afterload induced by retrograde nontransseptal balloon mitral valvuloplasty (RNBMV) on LA function in patients with mitral stenosis. LA pressure-area relations were obtained in 15 patients with mitral stenosis (8 with sinus rhythm, 7 with atrial fibrillation) before and after valvuloplasty, as well as in 15 normal subjects. LA pressure was recorded by a catheter-tipped micromanometer introduced retrogradely into the left atrium while LA area was recorded simultaneously using acoustic quantification. The areas of the A and V loops of the pressure-area relation as well as the LA chamber stiffness constant were calculated. RESULTS: Balloon valvuloplasty resulted in a significant increase in mitral valve area (p < 0.001) and a substantial reduction of the mean transmitral pressure gradient (p < 0.001) and mean LA pressure (p < 0.001). The area of the A loop in patients with sinus rhythm and the area of the V loop in those with atrial fibrillation increased significantly after completion of the procedure (p < 0.001). Furthermore, LA stiffness decreased in both groups. CONCLUSIONS: After RNBMV, there is a significant increase in LA pump function in patients with sinus rhythm, a significant increase in LA reservoir function in patients with atrial fibrillation and a significant reduction in LA stiffness in all patients. Marked alterations of the configuration of the LA pressure-area relation occur immediately after successful RNBMV in patients with mitral stenosis.

Adult↗
PubMed1998

Differentiating thrombus from pannus formation in obstructed mechanical prosthetic valves: an evaluation of clinical, transthoracic and transesophageal echocardiographic parameters.

OBJECTIVES: We sought to determine the clinical and echocardiographic parameters that differentiate thrombus from pannus formation as the etiology of obstructed mechanical prosthetic valves. BACKGROUND: Distinction of thrombus from pannus on obstructed prosthetic valves is essential because thrombolytic therapy has emerged as an alternative to reoperation. METHODS: We analyzed clinical, transthoracic and transesophageal echocardiography (TEE) data in 23 patients presenting with 24 obstructed prosthetic valves and compared the findings to pathology at surgery. RESULTS: Fourteen valves had thrombus and 10 had pannus formation. Patients with thrombus had a shorter duration from time of valve insertion to malfunction, shorter duration of symptoms, but similar New York Heart Association functional class at the time of operation. Patients with thrombus had a lower rate of adequate anticoagulation (21% vs. 89%; p=0.0028). Pannus formation was more common in the aortic position (70% vs. 21%; p=0.035). Abnormal prosthetic valve motion was detected by TEE in all cases with thrombus formation but in 60% with pannus (p=0.0198). Thrombi were larger than pannuses (total length 2.8+/-2.47 cm vs. 1.17+/-0.43 cm; p=0.038). This was mostly due to extension of thrombi into the left atrium in prosthetic mitral valves. Thrombi appeared as a soft mass on the valve in 92% of cases, whereas 29% of pannuses had a soft echo density (p= 0.007). Ultrasound video intensity ratio, derived as the videointensity of the mass to that of the prosthetic valve, was lower in the thrombus group (0.46+/-0.14 vs. 0.71+/-0.17, p=0.006). A videointensity ratio of <0.70 had a positive predictive value of 87% and a negative predictive value of 89% for thrombus. Duration from onset of symptoms to reoperation of <1 month separated thrombus from pannus formation. The best objective clinical parameter for prediction of thrombus was inadequate anticoagulation, whereas the best TEE parameters were qualitative and quantitative ultrasound intensity of the mass. The presence of either inadequate anticoagulation or a soft mass by TEE improved the predictive power of either parameter alone and was similar to that of ultrasound videointensity ratio. CONCLUSIONS: Duration of symptoms, anticoagulation status and qualitative and quantitative ultrasound intensity of the mass obstructing a mechanical prosthetic valve can help differentiate pannus formation from thrombus and may therefore be of value in refining the selection of patients for thrombolytic therapy of prosthetic valve obstruction.

Aortic Valve↗
PubMed1998

Influence of biological factors on lipid and fibrinogen measurements in young men. An epidemiological study in 2009 recruits.

AIMS: The aim of the present study was to detect significant relationships between lipid and fibrinogen measurements and several biological factors in young men. METHODS AND RESULTS: Medical history was obtained, and plasma lipids, lipoprotein (a) and fibrinogen levels were measured in 2009 male Greek army recruits (mean age 22.37+/-3.03 years) not taking any drugs. Plasma levels were as follows: total cholesterol, 171+/-34 mg x dl(-1), low density lipoprotein (LDL) cholesterol, 111+/-34 mg x dl(-1), high density lipoprotein (HDL) cholesterol, 45+/-10 mg x dl(1), and triglycerides, 74+/-32 mg x dl(-1). Lipoprotein (a) and fibrinogen were 18+/-13 and 278+/-67 mg x dl(-1). The atherosclerotic index, calculated as the ratio of total cholesterol/HDL, was 4+/-1. Analysis of multivariate models that included potentially confounding factors revealed the following: body mass index, season of year during which blood examinations were performed, alcohol consumption, and place of residence were found to be significantly associated with plasma levels of total cholesterol, LDL-cholesterol, fibrinogen and the atherosclerotic index in the pooled population. Season and physical activity were significantly associated with HDL-cholesterol, whereas season and family history of acute myocardial infarction were associated with triglycerides levels. Body mass index, family history of myocardial infarction and physical activity were associated with lipoprotein (a). CONCLUSION: Body mass index, season, alcohol consumption and place of residence are markers of plasma lipid profile and fibrinogen in young men. A family history of acute myocardial infarction and physical activity are related to lipoprotein (a).

Adolescent↗
PubMed1997

Aortic function in arterial hypertension determined by pressure-diameter relation: effects of diltiazem.

BACKGROUND: Aortic elastic properties, important determinants of left ventricular function and coronary blood flow, are compromised in hypertension. The aim of this study was to determine aortic function in hypertensive patients and in normal subjects before and after administration of diltiazem, a calcium antagonist widely used in the treatment of essential hypertension. METHODS AND RESULTS: The aortic pressure-diameter relation was obtained before and after diltiazem administration in 15 hypertensives and 15 control normotensives. Instantaneous diameter of the thoracic aorta was acquired with a high-fidelity intravascular catheter developed in our institution and previously validated. Instantaneous aortic pressure was measured simultaneously and at the same aortic level with a catheter-tip micromanometer. Energy loss due to the viscosity of aortic wall was measured from the area of the loop. Aortic distensibility was calculated using the formula 2 x (pulsatile change in aortic diameter)/([diastolic aortic diameter] x [aortic pulse pressure]). At baseline, aortic distensibility was lower and energy loss was greater in hypertensives than in normotensives (distensibility: 1.4+/-0.3 versus 3.5+/-0.7 cm2 x dyne(-1) x 10(-6), respectively, P<.001; energy loss: 14.1+/-3.3 versus 8.2+/-2.2 mm x mm Hg, respectively, P<.001). After diltiazem administration, aortic distensibility was increased, whereas energy loss was decreased in both hypertensives (peak response: distensibility, 2.0+/-0.4 cm2 x dyne(-1) x 10(-6), P<.001; energy loss, 9.3+/-1.6 mm x mm Hg, P<.001) and normotensives (peak response: distensibility, 5.2+/-0.5 cm2 x dyne(-1) x 10(-6), P<.001; energy loss, 5.0+/-1.2 mm x mm Hg, P<.001). CONCLUSIONS: Aortic elastic properties are compromised and energy loss due to aortic wall viscosity is increased in hypertensives compared with normotensives. Function of the aorta is improved in both hypertensive and normotensive subjects after the administration of diltiazem.

Adult↗
PubMed1997

Comparison of frequency of left atrial thrombus in patients with mechanical prosthetic cardiac valves and stroke versus transient ischemic attacks.

Transesophageal echocardiography performed in a group of 36 patients who had a first cerebral embolic event after implantation of a mechanical cardiac valvular prosthesis revealed that stroke is associated with the presence of left atrial thrombi more frequently than transient ischemic attacks. Intracardiac embolic sources other than thrombi are possibly related more often to the latter type of cerebral embolism in this patient population.

Aged↗
PubMed1997

Unfavorable effect of smoking on the elastic properties of the human aorta.

BACKGROUND: Smoking is a major risk factor for cardiovascular morbidity and mortality. Because previous studies have shown that smoking affects vasomotor response, we hypothesized that smoking may also acutely alter aortic elastic properties. METHODS AND RESULTS: We studied 40 male current and long-term smokers who underwent diagnostic cardiac catheterization for chest-pain evaluation. Twenty subjects (age, 48 +/- 2 years, mean +/- SEM) were randomly assigned to smoking and 20 (age, 47 +/- 2 years) to sham smoking studies. Aortic elastic properties were studied with the determination of the aortic pressure-diameter relation before smoking, every minute for the first 5 minutes after the initiation of smoking or sham smoking, and every 5 minutes for the following 15 minutes. Instantaneous diameter of the thoracic aorta was measured with a special ultrasonic dimension catheter developed in our laboratory and previously validated. Instantaneous aortic pressure was measured at the same site as was diameter with a Millar micromanometer. Smoking was associated with significant changes in the aortic pressure-diameter relation that denote deterioration of the elastic properties and were maintained during the whole study period: the slope of the pressure-diameter loop became steeper (baseline, 35.43 +/- 1.38; minute 1, 45.26 +/- 1.65; peak at minute 10, 46.36 +/- 1.69 mm Hg/mm; P < .001) and aortic distensibility decreased (baseline, 2.08 +/- 0.12; minute 1, 1.60 +/- 0.08; nadir at minute 5, 1.54 +/- 0.07 x 10(-6) cm2.dyne-1; P < .001). In contrast, no changes in aortic elasticity indexes were observed with sham smoking. CONCLUSIONS: Smoking is associated with an acute deterioration of aortic elastic properties. This effect of smoking may contribute to the unfavorable consequences of smoking on the cardiovascular system.

Aorta, Thoracic↗
PubMed1997

Impaired compensatory coronary artery enlargement in atherosclerosis contributes to the development of coronary artery stenosis in diabetic patients. An in vivo intravascular ultrasound study.

AIMS: Coronary arteries affected by atherosclerosis undergo focal compensatory enlargement, which can be detected by intracoronary ultrasound but not by angiography. Diabetic patients when compared with non-diabetics have a more accelerated progression of coronary artery disease and a more diffuse narrowing of the coronary arteries. Intracoronary ultrasound can clarify if this is due to less compensatory coronary artery enlargement as a response to atherosclerosis. METHODS AND RESULTS: Ten non-diabetic and 15 diabetic patients with coronary artery disease, with angiographically determined one- or two-vessel disease, underwent intracoronary ultrasound examination of the non-stenotic coronary artery. Forty-five sites with luminal stenosis, detected by intracoronary ultrasound, were analysed (15 in non-diabetics, 30 in diabetics). Vessel and lumen area, atherosclerotic plaque area and plaque composition were evaluated. Vessel area was also measured proximal and distal to the healthy segment. In the diabetic patients, there was less vessel area increase from the proximal healthy segment into the atherosclerotic segment than in the non-diabetic patients (99% separate-variance confidence intervals for differences between diabetics' and non-diabetics' means = 0.29 mm2, 2.71 mm2). The proximal plaque free vessel area, the atherosclerotic plaque area and plaque composition were similar between the two groups. CONCLUSION: Diabetics with atherosclerosis have less compensatory coronary artery enlargement than non-diabetics. This may explain the diffuse and accelerated course of coronary artery disease in these patients.

Constriction, Pathologic↗