Biomedical subjects

M Paterni

Publications and source records attributed to M Paterni.

At least 19 recordsLinked to original sources

PubMed2005

Protective effects of insulin during ischemia-reperfusion injury in hamster cheek pouch microcirculation.

OBJECTIVE: The effects of insulin (0.18 nM-0.18 microM) on reduced capillary perfusion, microvascular permeability increase and leukocyte adhesion induced by ischemia-reperfusion injury were investigated in the hamster cheek pouch microcirculation. To gain insight into the insulin's mechanism of action, the effects of its higher concentration (0.18 microM) were investigated after inhibition of tyrosine kinase (TK), nitric oxide synthase (NOS), protein kinase C (PKC), phosphatidylinositol 3-kinase and K+(ATP) channels, alone or in combination. Two concentrations for each inhibitor were used. METHODS: Microcirculation was visualized by fluorescence microscopy. Perfused capillary length, microvascular permeability, leukocyte adhesion to venular walls, vessel diameter and capillary red blood cell velocity were assessed by computer-assisted methods. Measurements were made at baseline (B), after 30 min of ischemia (I), and after 30 min of reperfusion (R). RESULTS: In control animals, perfused capillary length decreased by 63 +/- 5% of baseline at R. Microvascular permeability increased at I and R, while leukocyte adhesion was most pronounced in V1 postcapillary venules at R. Insulin dose-dependently preserved capillary perfusion at R (-28 +/- 6 and -15 +/- 6% of baseline), but was unable to prevent the increase in permeability at I (0.25 +/- 0.05 and 0.29 +/- 0.06 Normalized Grey Levels, NGL) and R (0.49 +/- 0.10 and 0.53 +/- 0.09 NGL), according to the concentrations. Adhesion of leukocytes was observed mostly in V3 venules at R (9 +/- 2 and 10 +/- 2/100 microm venular length, with the lower and higher concentration, respectively). Nitric oxide synthase inhibition by N(G)-nitro-L-arginine-methyl ester prior to insulin did not affect capillary perfusion at R (-18 +/- 3% of baseline with higher concentration), but prevented permeability increase (0.20 +/- 0.04 NGL, according to higher concentration) and reduced leukocyte adhesion in V3 venules at R (1.5 +/- 1.0/100 microm of venular length, with higher concentration). Blockade of K+(ATP) channels by glibenclamide prior to insulin decreased perfused capillary length at R (-58 +/- 6% of baseline with higher concentration), attenuated leakage at R (0.30 +/- 0.04 NGL, according to higher concentration) and caused leukocyte adhesion mainly in V1 venules at R (9.0 +/- 1.5/100 microm of venular length, with higher concentration). Inhibition of either TK, PKC or phosphatidylinositol 3-kinase did not affect microvascular responses to insulin. Simultaneous inhibition of TK and NOS did not increase protection. CONCLUSIONS: Insulin prevents ischemia-reperfusion injury by promoting capillary perfusion through an apparent activation of K+(ATP) channels and increase in nitric oxide release.

Alkaloids↗

PubMed2003

In vivo noninvasive identification of cell composition of intimal lesions: a combined approach with ultrasonography and immunocytochemistry.

PURPOSE: We investigated whether differences in cellular composition of the shoulder region of carotid plaque, a cell-rich, debris-free area, can be revealed with computer-driven analysis of ultrasound scans. METHODS: In 26 patients referred for carotid endarterectomy, the shoulder region of plaque eligible for surgical removal was identified with ultrasound scanning. Digital images were obtained and evaluated with a specially developed computer-driven system (Medical Image Processing [MIP]). The gray level distribution of the region of interest (ROI), along with some statistical parameters exploring the spatial distribution of pixels, such as entropy and second angular moment, were analyzed. In the specimen retrieved at surgery, the area corresponding to the ROI was selected. Cryosections were tested at immunocytochemistry with monoclonal antibodies specific to smooth muscle cells (SMCs), macrophages), and lymphocytes. Computerized image analysis was performed to quantify each cellular component of the lesion. RESULTS: Mean gray levels were related positively to the content of SMCs (r = 0.576, P =.002) and negatively to the content of macrophages (r = -0.555, P =.003). Lymphocytes did not show any correlation. Prevalence of SMCs, expressed as the ratio SMC/(SMC + macrophages), was related positively with entropy (r = 0.517, P =.007) and negatively with the second angular moment (r = -0.422, P =.032). The quartiles of gray level were useful for detecting significant differences in terms of cellular composition. CONCLUSIONS: Some cellular features of the shoulder region of plaque are associated with specific videodensitometric patterns evaluated with MIP. This approach enables in vivo noninvasive prediction and monitoring of cell composition of the shoulder region, and could be extended to study of the thickened intima.

Carotid Stenosis↗

PubMed2003

Coronary microcirculation into different models of left ventricular hypertrophy-hypertensive and athlete's heart: a contrast echocardiographic study.

The study was carried out in two different models of left ventricular hypertrophy: athlete's heart and essential arterial hypertension. Three groups of strictly age-matched males were studied: one group of 10 young adult untreated essential hypertensive patients (H), a second group of 10 athletes (A), and a group of 10 healthy individuals as controls (C). A Sonos 5500 echograph with S4 harmonic transducer was used with Levovist (ultrasonic tracer) before and after dipyridamole injection; digitised images of quantitative myocardial contrast echocardiography were collected with Power Harmonic Doppler. Angio images were analysed using dedicated PC software by placing a region-of-interest on the septum. Peak intensity, half-time (HT), the area under the curve of appearance and disappearance of microbubbles at 2/3 of PI, both in absolute and indexed values (/LVMi), were sampled. The per cent increase of PI after dipyridamole was significantly higher in C (+73%, P < 0.01) than in H (+31%) and in A (+33%) (P < 0.05). The area of appearance was significantly lower in H in comparison with C and A, both at rest and after vasodilatation. The disappearance area after dipyridamole was significantly higher in C and in A (+124%) than in H (+104%) (P < 0.05). Some hypothesis could be made: an impairment in the coronary microcirculatory function in hypertensive patients could be because of an in-crease in the arteriolar resistance. Angiogenesis and several different functional adaptations are the mechanisms that allow an optimal distribution of oxygen and of substrates to the hypertrophied myocardium of the athletes.

Adult↗

PubMed2002

Coronary microcirculation in essential hypertension: a quantitative myocardial contrast echocardiographic approach.

AIMS: The aims of the present study were: (a) to demonstrate whether quantitative myocardial contrast echocardiography can detect the increase in coronary flow induced by dipyridamole infusion vasodilation through the myocardial opacification due to the transit of microbubbles, both at rest and after dipyridamole induced vasodilation; (b) to explore the coronary microcirculatory function before and after dipyridamole in two different models: asymptomatic and relatively young hypertensive patients with a mild degree of left ventricular hypertrophy, and healthy controls. METHODS AND RESULTS: Two groups of strictly age-matched males were studied (case-control study): 10, relatively young and asymptomatic essential hypertensive patients with a mild degree of left ventricular hypertrophy with a normal left ventricular function, and 10 healthy controls. The main findings were: the microbubbles' appearance area was significantly lower in hypertensive patients than in controls (P<0.05) because of a significantly lower time to peak. The peak intensity at rest was higher in hypertensives than in controls (P<0.05); but the per cent increase after vasodilatory stimulus was significantly higher in controls (+71% in controls vs +31% in hypertensives; P<0.05). The microbubbles' disappearance area was comparable in both groups at rest; the per cent increase of this parameter after dipyridamole was significantly higher in controls (+124%) than in hypertensives (+90%) (P<0.05). The results achieved in this study documented that the coronary microcirculation in hypertensive patients presenting a mild degree of left ventricular hypertrophy, explored with quantitative myocardial contrast echocardiography, showed a different behaviour in comparison with controls, in the vasodilatory response to dipyridamole. CONCLUSION: The coronary microcirculation in hypertensives showed a reduced vasodilation capacity of the resistance arterioles under dipyridamole induced vasodilatation, and a possible impairment of the endothelium dependent vasodilation. This happened despite an increase in the left ventricular mass, where the relation between capillary bed distribution and hypertrophied myocardium (rarefaction phenomenon) is not completely respected.

Adult↗

PubMed2001

Stress-induced changes in subendocardial tissue texture in hypertrophic cardiomyopathy: an echocardiographic videodensitometric study.

BACKGROUND: Myocardial ischemia changes myocardial acoustic properties, inducing increase of integrated backscatter and blunting of cyclic variation of backscatter. Stress-induced subendocardial underperfusion has been demonstrated in patients with hypertrophic cardiomyopathy (HCM). AIM: To evaluate the potential of a videodensitometric approach in assessing transmural ultrasonic tissue changes in HCM during dipyridamole infusion. METHODS: Twenty-two patients (13 males, 50+/-12 years) with HCM underwent dipyridamole echo testing (DET). Myocardial gray levels amplitude was calculated off-line on digitized images in the left subendocardial (LV-endo), right subendocardial (RV-endo) region of the interventricular septum and posterior wall (long axis parasternal view). RESULTS: The thickness of the interventricular septum and posterior wall was 1.9+/-0.3 and 1.17+/-2.1 cm, respectively. In the LV-endo layer, the cyclic variation was blunted during DET (rest = 37+/-14 vs. DET 27+/-20%, p < 0.02). In the RV-endo layer and posterior wall, no changes occurred. In the LV-endo layer of the septum, blunting of cyclic variation was more pronounced in the 10 patients with than in the 12 without ST-segment depression during DET (21.2+/-14.7% vs. 43.8+/-15.8, p < 0.01). CONCLUSIONS: In HCM patients, DET induced blunting of cyclic variation without the evidence of wall motion abnormalities. This reduction was more pronounced when electrocardiographic signs of ischemia were simultaneously elicited by DET.

Adult↗

PubMed2001

111In platelet scintigraphy for the noninvasive detection of carotid plaque thrombosis.

BACKGROUND AND PURPOSE: Thrombosis on atherosclerotic lesions in the large extracranial arteries is the main cause of embolization in the distal cerebral circulation and thus is involved in the pathogenesis of ischemic stroke. The assessment of biological characteristics of lesions that are predictive of thrombotic complications might help in stratification of the risk for stroke but is currently imperfect. METHODS: We compared the performance of (111)In-platelet scintigraphy with blood pool subtraction, ultrasound-based tissue texture analyses, and transcranial Doppler techniques in their ability to predict the occurrence of superficial thrombosis or the presence of a lipid pool in carotid artery plaque specimens removed at the time of carotid endarterectomy in 22 patients with unilateral carotid artery stenosis of >70%. RESULTS: Positivity at (111)In-platelet scintigraphy was present in 8 patients and correctly identified the presence of thrombosis superimposed on a complicated plaque. Neither tissue texture analysis nor emboli detection by transcranial Doppler, performed in 12 patients, significantly identified plaque thrombosis. None of the techniques used were able to detect the presence of a significant lipid pool inside the plaque. CONCLUSIONS: Indium-platelet scintigraphy is an accurate noninvasive diagnostic tool to detect thrombotic complications in carotid plaques. Prospective studies should assess its ultimate value in risk stratification, possibly to guide the decision of whether to perform endarterectomy in selected patient categories.

Aged↗

PubMed2001

Microalbuminuria, pulse pressure, left ventricular hypertrophy, and myocardial ultrasonic tissue characterization in essential hypertension.

Microalbuminuria (UAE) may be considered a marker of systemic vascular dysfunction, while pulse pressure (PP) is an indicator of the stiffness of vascular conduits. Both these parameters, together with left ventricular hypertrophy (LVH), are linked to cardiovascular morbidity in hypertensive patients. The aim of this study was the analysis of the possible relationships among UAE, PP, and LVH with ultrasonic myocardial textural parameters, which are altered in hypertensives patients. A group of male (n = 70) essential hypertensive patients (mean age: 58 +/- 7 yr) was analyzed with a group of age-comparable normotensive healthy subjects as controls (n = 32). Ambulatory blood pressure monitoring (ABPM) was performed with an oscillometric monitor; UAE was measured by nephelometry. A conventional 2D-Doppler echocardiography (to analyze left ventricular mass: LVM) and a quantitative analysis of the echocardiographic digitized imaging with the use of a calibrated digitization system (to calculate the septum and the posterior wall textural parameters) were performed on all subjects. The myocardial mean gray level was calculated to derive the cyclic variation index (CVI). The CVI was significantly lower in hypertensives both for the septum (- 16.3 +/- 22.8 vs 34.7 +/- 15.3%; p < 0.001) and for the posterior wall (- 15.2 +/- 23.6 vs 38.2 +/- 15.4%; p < 0.001). A significant negative correlation was found between logUAE and the CVI of the septum (r = -0.42; p < 0.001), between the PP and the CVI of the septum (r = -0.40; p < 0.002) and between the CVI and the LVM (r = -0.38; p < 0.001). Multiple regression analysis having as dependent variable the CVI at septum level showed as significantly related independent variables: PP (p < 0.01), logUAE (p < 0.001), and LVM (p < 0.05) (multiple R: 0.76, squared multiple R: 0.57; p < 0.001). It was found that LVM, logUAE, and PP are all correlated with textural parameters, and the CVI can be considered a sensitive parameter in the identification of an abnormal myocardial texture in hypertension. A high level of arterial stiffness and the presence of vascular dysfunction in essential hypertension could participate in the determination of myocardial alterations and permit the identification of patients with the worst prognosis in terms of morbidity or mortality due to cardiovascular events.

Albuminuria↗

PubMed2001

Ultrasonic myocardial tissue characterization: a methodological review.

Ultrasonic myocardial tissue characterization represents a relatively new diagnostic tool which allows integration of the conventional echocardiographic evaluation, in order to obtain specific textural parameters which reflect the myocardial ultrastructural texture. In particular, through this approach it is possible to obtain two different types of information: the first is static and consists of the absolute myocardial echo intensity that reflects the ultrastructural myocardial changes in different diseases; the second is dynamic and is related to the variations of echo intensity during the cardiac cycle which seem to be linked, even though not linearly, to the intrinsic myocardial contractility. Our research group has extensively applied this methodological approach to different pathophysiological models, in particular to essential hypertension. In the present review the technological evolution of the method and comparison with other research groups' experience with the specific pathophysiological models, are shown and discussed.

Echocardiography↗

PubMed2000

Ultrasonic myocardial textural parameters and midwall left ventricular mechanics in essential arterial hypertension.

BACKGROUND: The evaluation of the systolic left ventricular performance in hypertensive patients presents some problems related to left ventricular hypertrophy (LVH) which alters the ventricular geometry. The videodensitometric textural ultrasonic analysis of hypertensive myocardium has provided evidence of impairment in the cyclic variation of the mean gray level. This might be considered as an index of intrinsic myocardial function. OBJECTIVES: The aim of the present study was to analyse the connection between the midwall fractional shortening and end-systolic stress. The ultrasonic textural parameters in hypertensive patients, arranged in different groups according to the level of LVH and relative wall thickness, were also evaluated. METHODS: A group of age-matched (58 +/- 7 years) male essential hypertensive patients (n = 70) were compared to a group of normotensive and healthy subjects used as controls (n = 32). All subjects performed a conventional 2D-Doppler echocardiography to analyse the left ventricular performance. A quantitative analysis of the echocardiographic digitised imaging was also carried out with the help of a calibrated digitization system in order to calculate the septum and the posterior wall textural parameters. The myocardial mean gray level was calculated to derive the cyclic variation index (CVI). RESULTS: When subjected to a higher meridional end-systolic stress, the hypertensive patients showed a significantly lower midwall fractional shortening than the control patients. The CVI was also significantly lower in the hypertensives group, both for the septum wall (-16.3 +/- 22.8 vs34.7 +/- 15.3%; P < 0.001) and the posterior wall (-5.2 +/- 23.6 vs 38.2 +/- 15.4%; P < 0.001). A significant correlation was found between the midwall fractional shortening (MFS) and the textural parameters, and between these two variables and the end-systolic stress. CONCLUSION: The CVI was found to be a highly sensitive parameter in the identification of abnormal echodensity in essential hypertension. The CVI was significantly lower in patients with concentric hypertrophy in comparison with other left ventricular geometric models. This parameter could be considered as an index of the intrinsic myocardial function, being related, in essential hypertension, to midwall fractional shortening and to end-systolic stress. Journal of Human Hypertension (2000) 14, 9-16.

Blood Pressure↗

PubMed2000

Ultrasonic myocardial textural analysis in subclinical hypothyroidism.

BACKGROUND: In subclinical hypothyroidism (sHT), a condition in which impaired hormone synthesis is compensated by thyroid-stimulating hormone (TSH) hypersecretion, previous studies have suggested the presence of disturbances in left ventricular (LV) function. OBJECTIVES: Our goal was to investigate LV structure and function through the combined use of conventional Doppler echocardiography and ultrasonic videodensitometry. METHODS: We studied 16 patients with sHT (aged 32+/-12 [mean +/- SD] years) who had raised TSH levels (> 3.6 mIU/L) but normal levels of free thyroid hormones (free thyroxine [FT(4)] and free triiodothyro-nine [FT(3)]), and 16 carefully age- and sex-matched euthyroid subjects. Transmitral flow Doppler analysis and quantitative analysis of the echocardiographic digitized images were performed in all study subjects. Textural parameters of the septum and posterior wall were obtained as mean gray levels, which were then used to calculate the cyclic variation index (CVI), that is, the percent change in mean gray levels between diastole and systole. RESULTS: Patients with sHT had a significantly higher LV mass index (92 +/- 16 versus 76 +/- 16 g.m(2), P<.01) and isovolumic relaxation time corrected for heart rate (IVRTc) (2.9 +/- 0.6 versus 2.5 +/- 0.6, P<.04) than did controls. On videodensitometry, patients had lower CVIs both for the septum (-5% +/- 22% versus 33% +/- 9%, P<.0001) and the posterior wall (10% +/- 26% versus 49% +/- 18%, P<.0001). IVRTc discriminated only 25% of the patients from the controls, whereas CVI analysis correctly identified 85% of the patients with sHT (P<.002). Furthermore, CVI values were found to be significantly related to serum FT(4) and FT(3) concentrations in a direct fashion, and to serum TSH levels in an inverse fashion. CONCLUSIONS: Subclinical hypothyroidism is associated with changes in videodensitometric myocardial structure. These changes, which are not accurately detected by conventional or Doppler echocardiography, are quantitatively related to loss of thyroid function and could represent an early sign of myocardial damage in hypothyroidism.

Adult↗

PubMed2000

The potential prognostic value of ultrasonic characterization (videodensitometry) of myocardial tissue in essential arterial hypertension.

BACKGROUND: Left ventricular hypertrophy (LVH) and the geometric shape of the left ventricle are well-established important risk factors for cardiovascular morbidity and mortality in the hypertensive population. Videodensitometry is an alternate echocardiographic approach to the study of myocardial structural and functional alterations in essential hypertension. OBJECTIVES: To analyze the behavior of the ultrasonic videodensitometric parameter for various subgroups of a hypertensive population; first according to the severity of LVH (group A, without LVH; group B, with mild-to-moderate LVH; and group C, with severe LVH) and second according to geometric adaptation of left ventricle to pressure-volume overload of essential hypertension (group NG, normal geometry; group CR, concentric remodeling; group CH, concentric hypertrophy; and group EH, eccentric hypertrophy). METHODS: For 70 male, essential hypertensive patients and 32 normotensive healthy subjects matched for age (58 +/- 7 years) and sex as controls (group N) we performed ambulatory blood pressure measurements for the evaluation of 24 h mean systolic and diastolic blood pressures, conventional two-dimensional Doppler echocardiography to evaluate left ventricular performance and left ventricular mass index, and digitization of left ventricular parasternal long-axis echocardiographic images. For regions of interest selected within the septum and the posterior wall, the mean gray levels were calculated at end-systole and end-diastole. The resulting values were used to estimate the percentage cyclic variation index (CVI). RESULTS: The results according to left ventricular mass index were CVI for septum group N 34.7 + 16.3%; group A - 0.18 +/- 16%, group B - 13 +/- 19%, and group C - 22 +/- 12% (P < 0.001); and CVI of posterior wall, group N 38.2 +/- 15.4%, group A -0.75 +/- 16%, group B -16 +/- 16% and group C -16 +/- 13% (P< 0.001). According to left ventricular geometry CVI for septum were group NG 0.6 +/- 24%, group CR 1.9 +/- 17%; group CH - 25.4 +/- 18%, and group EH -17.1 +/- 20% (P < 0.01). CVI of posterior wall were group NH -5.8 + 24%, group CR 6.4 +/- 23%, group CH -29 +/- 20%, group EH -20 +/- 21 (P < 0.01). CONCLUSIONS: Our results demonstrate that subjects with high left ventricular masses and those with concentric hypertrophy, which have the worst prognostic impacts, have the most significant changes in CVI. Furthermore, videodensitometric findings are quite different even among the subgroups with mild-to-moderate left ventricular hypertrophy and eccentric hypertrophy. Therefore this videodensitometric approach could provide some useful information for better definition of cardiovascular risk in hypertension.

Blood Pressure↗

PubMed1999

Can insulin action induce myocardial texture alterations in essential hypertension?

The prevalence of hyperinsulinemia/insulin resistance in hypertensive individuals, as well as the effects of insulin on myocytic and fibroblastic growth, are well known in both epidemiologic and animal models. To check whether there are any links between ultrasonic myocardial texture parameters and insulin level in essential hypertensives, we compared 18 essential hypertensive men (Group 1, H) with 18 age- and gender-matched healthy controls (Group 2, C) (age, 57 +/- 10 years). For all study subjects we performed ambulatory blood pressure monitoring (ABPM); conventional 2-D Doppler echocardiography for the assessment of the left ventricular mass index (LVMi) and function; quantitative analysis of digitized echocardiographic images for evaluation of cyclic variation (CVI) of mean gray level (MGL) at the septum and posterior wall levels; and 75-g 3-h oral glucose tolerance test (OGTT) for analysis of area under glycemic curve (AUGC, g/min/dL) and insulinemic curve (AUIC, mU/min/mL), as well as serum glucose and insulin peaks. Both the daily mean blood pressure (H: 109 +/- 4.6 v C: 94.6 +/- 4.6, P < .0001) and LVMi (adjusted for body surface) (H: 133 +/- 24 v C: 97 +/- 21 g/m2, P < .0001) were significantly higher in hypertensives. Values for AUIC were significantly higher in hypertensives (10.37 +/- 5.53 v 6.33 +/- 5.28), P < .032); CVI was also significantly higher in group C, for both septum (C: 40.2 +/- 16.9 v H: 15.9 +/- 18.1, P < .0001) and posterior wall (C: 44.5 +/- 19.6 v H: 20 +/- 17.5; P < .0001). There was a significant inverse correlation between AUIC and CVI for both septum (r: -0.57, P < .001) and posterior wall (r: -0.50, P < .002). The significantly higher impairment of myocardial ultrasonic texture and the higher level of the AUIC insulinemia in hypertensives, as well as the significant inverse relationship between CVI and hyperinsulinemia, are our major findings. Hyperinsulinemia/insulin resistance could cause an altered collagen/muscular ratio, which could potentially explain, at least in part, the CVI alterations detected in hypertensive patients.

Adolescent↗

PubMed1999

Ultrasonic videodensitometric analysis of myocardium in end-stage renal disease treated with haemodialysis.

BACKGROUND: The aim of this study was to investigate videodensitometric parameters of the myocardium, in dialysis patients, who represent a complex pathophysiological model of pressure volume overload, and in essential hypertensive patients with the same level of left ventricular mass. METHODS: We compared a group of male dialysis patients (D) with two groups: hypertensive patients (H) with comparable left ventricular mass and normotensive healthy subjects as controls (C). The groups (n=15 each) were age- (53 +/- 9 years) and gender-matched. Quantitative analysis of echocardiographic digitalized imaging was performed to calculate the mean grey level (MGL) and cyclic variation index (CVI). RESULTS: The haemodialysis patients had a significantly lower CVI compared with hypertensives and controls both for septum (D): -2.5 +/- 17.4% vs (H); 11.8 +/- 17% vs (C); 43.2 +/- 15.4% (P<0.001) and for posterior wall (D): -10.1 +/- 261% vs (H); 14.2 +/- 14.7% vs (C); 46.6 +/- 17.2% (P<0.001). A significant inverse relationship was found between intact parathyroid hormone (iPTH) and CVI. CONCLUSION: Abnormalities of two-dimensional echocardiographic grey level distribution are present in both haemodialysis patients and hypertensive patients, but seem unrelated to the degree of echocardiographic hypertrophy. These videodensitometric myocardial alterations are significantly higher in dialysis patients than in hypertensive patients with the same extent of left ventricular hypertrophy. The iPTH level may play a role in the development of the ultrasonic myocardial alterations, which probably represent an early stage of uraemic cardiomyopathy.

Case-Control Studies↗

PubMed1999

Effects of anabolic-androgenic steroids on weight-lifters' myocardium: an ultrasonic videodensitometric study.

BACKGROUND: Recent bioptical data have shown that in weight-lifters (WL) under the pharmacological effects of anabolic-androgenic steroids (AAS), a focal increase in myocardial collagen content might occur as a reparative mechanism against a myocardial damage. OBJECTIVE: The aim of this study was to investigate whether by using videodensitometry an early identification of the changes in myocardial texture is possible or a potential sign of myocardial damage, which can potentially occur in WL who have used AAS. METHODS: Ten males WL (mean age: 32+/-6 yr) who had regularly used AAS (users), were compared with 10 male WL at same training level (nonusers), who had not used any drugs and with 10 healthy sedentary controls (controls). The three groups were age and sex-matched. Echocardiographic parietal, septal thickness, and left ventricular mass (LVMbs) were evaluated. Left ventricular systolic and diastolic functions were evaluated with Doppler examination. Quantitative analysis of echocardiographic digitized data was carried out with a calibrated 256 gray level digitization system, in order to calculate the mid-septum and the mid-posterior mean gray level (MGL) and to derive the cyclic variation index (CVI), i.e., the percent MGL variation during cardiac cycle. RESULTS: The weight and relative body mass index were significantly higher in WL (P<0.001); also the diastolic blood pressure was slightly but significantly higher in users in comparison both with nonusers and controls (P<0.01). Systolic and diastolic functional parameters overlapped in the three groups. LVMbs was significantly higher in users (145+/-17) and in nonusers (122+/-27) vs. C (104+/-18 g x m(-2)) (p<0.001). CVI at septum level showed significant differences: users: (2.3+/-31%) vs nonusers: (23+/-8) and controls (29+/-5) (P<0.005); although no significant difference was found between nonusers and controls. CVI at posterior wall level followed a similar pattern. No relationship was found between CVI and LVMbs or wall thickness. DISCUSSION: As brought out by videodensitometry, despite an increase in septal and parietal thickness and consequently in LVMbs, the physiological pressure overload that happens in WL during sport activities, in absence of any drugs, does not modify the myocardial ultrasonic texture. The abuse of AAS in WL, on the other hand, determines some alterations of the myocardial textural parameters. The real significance of these changes of myocardial texture detected with videodensitometry in WL who use anabolic-androgenic steroids, present also in the absence of other systolic and diastolic left ventricular functional indexes alterations, needs to be further explored with a larger population through the comparison with endobioptical data and with a follow-up study approach.

Adult↗

PubMed1999

Ultrasonic myocardial texture versus Doppler analysis in hypertensive heart: a preliminary study.

-Doppler-derived parameters of transmitral flow are useful indices of diastolic dysfunction in the hypertensive heart. Different degrees of myocardial involvement in hypertensive heart can be detected by videodensitometric myocardial textural analysis. The aim of this study was to compare Doppler-derived and ultrasonic videodensitometric parameters in the differentiation of healthy hearts from hypertensive hearts. We compared a group of age-matched (59+/-9 years) male essential hypertensive patients (n=53) with normotensive healthy subjects as controls (n=32). All subjects provided ambulatory blood pressure measurements for the evaluation of 24-hour mean systolic and diastolic blood pressure. A transmitral flow Doppler analysis was performed on all subjects. A quantitative analysis of the echocardiographic digitized imaging was performed with the help of a calibrated digitization system to calculate the septum and the posterior wall textural parameters. The myocardial mean gray level (MGL) was calculated to derive the cyclic variation index (CVI): (MGLend-diastolic-MGLend-systolic)/MGLend-diastolic x100. When compared with controls, the hypertensive patients showed a significantly lower CVI for both septum (-11.1+/-26.8% versus 34. 7+/-16.3%; P<0.001) and posterior wall (-11.2+/-27.6% versus 38. 2+/-15.4%; P<0.001). Individual analyses for the ratio of peak transmitral flow velocity in early diastole to the peak transmitral flow velocity in late diastole showed that only 24% of the patients (13/53) were discriminated from normal subjects by this parameter. Individual analyses for CVI, however, at both septum and posterior wall levels, showed that 74% of the patients (39/53) were discriminated from normal subjects by this second parameter. In comparison with Doppler-derived indices of diastolic filling, the videodensitometric parameters showed a significantly higher ability to discriminate between hypertensive subjects and normal controls.

Aged↗

PubMed1999

Ultrasonic videodensitometric analysis in scleroderma heart disease.

OBJECTIVES: Symptomatic cardiac involvement is a frequent visceral complication of systemic sclerosis that can affect the overall prognosis of the disease. The aim of the present study was to detect preclinical myocardial alterations in patients with systemic sclerosis using ultrasonic videodensitometric analysis. METHODS: Fifty patients with systemic sclerosis [five men, aged 48.8 +/- 11 years (mean +/- SD), range 22-65 years] with normal left ventricular function and 25 age- and sex-matched healthy controls were investigated. Exclusion criteria were the presence of positive maximal exercise stress, arterial hypertension, renal involvement and diabetes. Echocardiographic images were digitized using a real-time video-digitizer Quantitative texture analysis was performed on data from the septum and posterior wall, and mean gray level (MGL) histograms at both end-diastole (d) and end-systole (s) were obtained. The cyclic variation index (CVI) was calculated according to the formula [(MGLd - MGLs)/MGLd] x 100. Left ventricular mass, body surface corrected, was calculated according to the Penn convention. RESULTS: The pattern of variations of mean gray level during the cardiac cycle was totally different from that of the controls; this finding, probably related to myocardial fibrosis, was detected in the large majority of patients with systemic sclerosis (90%). In particular, CVI, which is the expression of the intrinsic myocardial structural function, was significantly lower than in controls (septum -31 +/- 38% versus 36 +/- 9%, P < 0.0001; and posterior wall -19 +/- 33% versus 51 +/- 20%, P < 0.0001). CONCLUSIONS: Ultrasonic videodensitometric analysis is a non-invasive, feasible method of detecting myocardial alterations in patients with systemic sclerosis, which could be related to both fibrosis and microcirculatory abnormalities. The potential role of these abnormalities in the pathogenesis of ventricular dysfunction should be investigated further.

Adult↗

PubMed1998

Detection of perfusion defects during coronary occlusion and myocardial reperfusion after thrombolysis by intravenous administration of the echo-enhancing agent BR1.

The purpose of this study was to detect myocardial perfusion defects as a result of coronary occlusion and myocardial reperfusion after thrombolysis with intravenous (i.v.) administration of the echo contrast agent BR1 (Bracco Research, Switzerland), which consists of microbubbles (median diameter 2.5 microm) containing sulfur exafluoride in a phospholipidic shell. To generate a coronary thrombosis, a copper coil was advanced into the left circumflex coronary artery in eight anesthetized dogs with opened chest cavities. Coronary occlusion occurred 18 +/- 10 minutes after the insertion of the coil and was documented both by an electromagnetic flow meter (as zero blood flow) and by radiolabeled microspheres (as myocardial perfusion defect). After 2 hours of occlusion, streptokinase was infused i.v.; reperfusion was documented by both the flow-meter and microspheres. Left ventricular cavity enhancement was apparent after all contrast injections. Peak cavity intensity did not increase with dose and was not affected by signal processing (suggesting signal saturation), whereas the duration of contrast effect significantly increased with the dose (from 26 +/- 16 to 147 +/- 74 seconds). Myocardial contrast intensity also increased after contrast (from 15 +/- 12 to 21 +/- 18 gray level/pixel, p < 0.001). Contrast echo detected myocardial perfusion defects (corresponding to 17% +/- 11% of LV cross-sectional area) in all the injections performed during coronary occlusion and detected myocardial reperfusion with a sensitivity of 50% versus microspheres. The extent of perfusion defects by contrast echo showed a good correlation with microspheres (r = 0.73). Myocardial reperfusion was not detected by changes in heart rate, aortic pressure, pulmonary arterial pressure, cardiac output, left ventricular fractional area change, or wall-motion score index. Hemodynamic parameters were not affected by contrast injections. Thus, the i.v. administration of BR1 allows us to accurately detect myocardial perfusion defects during coronary occlusion and, to a lesser extent, myocardial reperfusion after thrombolysis.

Animals↗

PubMed1998

Ultrasonic myocardial texture in hypertensive mild-to-moderate left ventricular hypertrophy: a videodensitometric study.

Myocardial texture analysis of two-dimensional echocardiographic gray level distribution is abnormal in hypertensive patients with severe increase of left ventricular mass. The aim of this study was to investigate the behavior of this parameter in hypertensive patients with absent-to-moderate left ventricular hypertrophy, more representative of the overall hypertensive population. We compared male essential hypertensive patients, with absent or mild-to-moderate left ventricular hypertrophy, with normotensive sedentary healthy subjects as controls. The groups (n = 18 each) were age- (+/- 2 years) and sex-matched. All subjects performed ambulatory blood pressure measurements for the evaluation of 24 h mean systolic and diastolic blood pressure. Quantitative analysis of echocardiographic digitized imaging was performed through a calibrated 256 gray level digitization system to calculate midseptum and midposterior end-diastolic and end-systolic first and second order textural analysis. In particular were observed the mean gray level cyclic variations to deriving the cyclic variation index (CVI). The hypertensives showed a significantly lower CVI compared with controls both for septum (P < .001) and for posterior wall (P < .0001). No significant relationships were found between CVI and relative diastolic thickness both of septum and posterior wall. Conversely, a significant inverse relationship was found between systolic arterial pressure values and CVI both of septum and posterior wall. Abnormalities of two dimensional echocardiographic gray level distribution are present also in hypertensive patients with absent or with mild-to-moderate levels of left ventricular hypertrophy, but seem unrelated to the degree of echocardiographic hypertrophy as such. Changes in collagen network distribution or microcirculatory alterations, secondary to pressure-volume overload per se or to other complex humoral factors, could explain these abnormalities. Further work is needed to establish the clinical, therapeutic, and prognostic implications of these findings.

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