M Paterni

Università di Pisa, Pisa, Tuscany, Italy

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Publications (75)202.56 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Context Hyperglycemia is associated with a higher carotid intima-media thickness (IMT), however it is not established whether this increase reflects early atherosclerotic changes or adaptive remodeling responding to hyperglycemia-induced alteration in mechanical properties of the arterial wall. Objective Aim of this study was to compare carotid geometry and circumferential wall stress between patients with type 2 diabetes mellitus (T2DM) and healthy controls, and to evaluate the associations between chronic glucose exposure and measures of arterial structure and function. Design Case-control and cross-sectional study Setting Institutional practice Participants One hundred thirty-three T2DM patients free of cardiovascular complications and 133 healthy controls with normal glucose metabolism, matched for sex, age, body mass index Main Outcome Measures Common carotid artery (CCA) IMT, luminal diameter, wave speed (WS) and local pulse pressure (PP) Results As compared to controls, T2DM patients had higher (P<0.0001) CCA IMT (640±81 vs 709±118 μ m), luminal diameter (6.12±0.67 vs 6.69±0.56 mm) and brachial PP (47±7 vs 57±12 mmHg), whereas luminal radius to IMT ratio (4.8±0.7 vs 4.8±0.8, P=0.57) and circumferential wall stress (49.0±8.3 vs 50.6±10.3 kPa, P=0.26) were comparable between the two groups. In T2DM patients, glycosylated hemoglobin was independently related to CCA WS and local PP, but not to IMT that was determined by age, local PP and luminal diameter. Conclusions This study suggests that increase in IMT associated with a higher glucose exposure might reflect an adaptive remodeling counteracting raise in pulsatile strain and preventing increment in circumferential wall stress caused by luminal enlargement of stiff arteries.
    The Journal of clinical endocrinology and metabolism. 07/2014;
  • The Journal of clinical endocrinology and metabolism 09/2008; 93(9):3325-32. · 6.50 Impact Factor
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    ABSTRACT: An independent association between obesity and preclinical carotid atherosclerosis has been demonstrated, however, the pathophysiological links were not clearly established. Body composition (BC) influences systemic hemodynamics and may participate in the remodeling of common carotid artery (CCA), independently of risk factors. This study evaluated the association between CCA structure and BC in a large population of healthy subjects. This was a cross-sectional study. The study was conducted at 19 European centers. The study included 627 healthy subjects (252 men, age 30-60 yr, body mass index 17-40 kg/m2). CCA luminal diameter and intima-media thickness were measured on digitized ultrasound images. Acoustic properties of CCA wall were evaluated by digital densitometric analysis and described in terms of mean gray level. BC was assessed by electrical bioimpedance. Insulin sensitivity (euglycemic hyperinsulinemic clamp) and plasma adiponectin levels were measured. Associations between CCA structure, age, BC, and metabolic and atherosclerotic risk factors were analyzed by multivariate regression models. Independent factors affecting CCA diameter were fat-free mass and waist girth (standardized r = 0.44 and 0.12; P < 0.01 and < 0.0001; R2 = 0.35); independent correlates of intima-media thickness were age, CCA diameter, systolic blood pressure, and low-density lipoprotein-cholesterol (standardized r = 0.39, 0.25, 0.10, and 0.14; P < 0.005-0.0001; R2 = 0.40). The mean gray level of carotid wall was independently associated with age and waist girth (standardized r = 0.23 and 0.12; P < 0.0001 and = 0.001; R2 = 0.30). Findings of this cross-sectional study suggest that BC modulates CCA diameter, and may induce adaptive changes in carotid wall thickness, independently of metabolic and atherosclerotic factors. Central adiposity modifies the acoustic properties of carotid wall.
    Journal of Clinical Endocrinology &amp Metabolism 08/2008; 93(9):3325-32. · 6.43 Impact Factor
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    ABSTRACT: Regular endurance exercise has been shown to reduce the age-related increase in arterial stiffness that is thought to contribute to cardiovascular risk. The aim of this study was to evaluate the influence of age and habitual physical activity on carotid artery wall thickness and stiffness in a population of young to middle-age subjects at low cardiovascular risk. The study population consisted of 432 healthy subjects (166 men; mean+/-SD age, 43+/-8 years; range, 30 to 60 years) free of carotid atherosclerosis and with low coronary heart disease risk, as determined by the Framingham prediction score sheet. All subjects underwent B-mode ultrasonography of the extracranial carotid arteries and physical activity assessment by actigraph, an accelerometer capable of monitoring the intensity and duration of body movements. The intima-media thickness of the common carotid artery was measured on ultrasound images, along with systodiastolic changes in luminal diameter, and indices of carotid stiffness were calculated. Intima-media thickness and carotid stiffness increased with age in both men and women (r=0.24 to 0.52, P<0.001). The magnitude of objectively assessed daily physical activity was negatively related to indices of carotid stiffness (r from -0.20 to -0.25, P<0.001) but not to intima-media thickness. In multivariate regression analyses that included several cardiovascular risk factors such as obesity, blood pressure, plasma lipids, and smoking habits, age and physical activity were independently related to carotid stiffness. This study provides cross-sectional evidence that habitual physical activity is inversely related to the age-dependent increase in carotid wall stiffness in a young to middle-age population at low risk.
    Stroke 09/2007; 38(9):2549-55. · 6.16 Impact Factor
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    ABSTRACT: In the hypertensive heart, epicardial arteries are not enlarged, despite increased total coronary flow related to augmented cardiac workload, wall stress, and left ventricular (LV) mass. The aims of this study were to assess the impact of different hemodynamic factors and LV mass on baseline left main coronary artery (LMA) size in hypertensive LV hypertrophy (LVH) and physiologic LVH, used as a pressure-independent model of hypertrophy. In 104 subjects without coronary disease (26 normotensive subjects without LVH, 15 athletes with physiologic LVH, and 63 untreated hypertensive subjects [28 without and 35 with LVH]), LMA size and coronary flow reserve (CFR) were measured by transesophageal echocardiography, and LV mass, volumes, stroke work, and wall stress were measured by transthoracic echocardiography. The LMA area in normotensive control subjects, athletes, and hypertensive subjects without and with LVH was 13.2 +/- 4.2, 17.5 +/- 2.9, 10.1 +/- 3.2 and 13.1 +/- 3.9 mm(2). In normotensive control subjects, LMA size increased with body surface area, rate-pressure product, stroke work, and LV mass or wall thickness (r = 0.39, 0.39, 0.47 and 0.67 or 0.62, P < .05-0.01). In athletes with physiologic LVH, LMA area increased with CFR (0.65, P < .01). In the whole hypertensive population, LMA lumen increased with LV mass (r = 0.40, P < .01), and decreased with office systolic blood pressure (r = -0.48, P < .01). In the hypertensive LVH, baseline LMA area is not increased and is inversely related to office systolic blood pressure. In the physiologic LVH, increase in baseline LMA size seems to reflect effect of high-flow stimuli.
    American Journal of Hypertension 03/2007; 20(3):279-84. · 3.67 Impact Factor
  • Artery Research 01/2007; 1(2):70-70.
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    01/2005;
  • High Blood Pressure & Cardiovascular Prevention 01/2005; 12(3).
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    ABSTRACT: Aims of this study were to: (1) demonstrate whether quantitative myocardial contrast echocardiography could detect an index of myocardial blood flow reserve through the analysis of refilling curves generated by microbubble transit into myocardium both at rest and after vasodilatation induced by dipyridamole; and (2) explore with this method myocardial microcirculatory function in two different models (ie, patients with essential hypertension and control subjects). Two groups of strictly age-matched men were studied (case-control study): 12 patients who were adults (28.2 +/- 0.2 years) and asymptomatic with never-treated essential hypertension, a mild degree of left ventricular hypertrophy, and normal left ventricular function; and 12 control subjects. Quantitative myocardial contrast echocardiography was performed in all study participants. We used second-generation ultrasound microbubbles as echocardiography contrast agent. Real-time color-coded power modulation was performed with a phased-array system interfaced to a S3 transducer (1.3-3.6 MHz). In control subjects there was little increase in myocardial blood volume (30%) between basal and hyperemic status (P <.05); in patients with hypertension this parameter increased by 22% (P <.05). Myocardial blood velocity increased after dipyridamole by 270% in control subjects (P <.01), whereas for patients with hypertension this parameter increased only by 150% (P <.02). The index of myocardial blood flow reserve was significantly lower for patients with hypertension than in control subjects (3.3 +/- 0.3 vs 4.4 +/- 0.3, respectively; P <.01). Results of our study documented that myocardial microcirculation in young adult patients with hypertension showed an early impairment in the vasodilatation capacity of the resistance arterioles under dipyridamole-induced hyperemia, as demonstrated by a reduction of myocardial blood flow reserve. Myocardial blood velocity increased after dipyridamole induction in control subjects, whereas patients with hypertension showed a significantly lesser increase. Myocardial blood flow reserve was significantly lower for patients with hypertension because of an early impairment in vasodilatation capacity of resistance arterioles under dipyridamole-induced hyperemia.
    Journal of the American Society of Echocardiography 10/2004; 17(10):1037-43. · 4.28 Impact Factor
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    ABSTRACT: 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. 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. 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. 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.
    Journal of Vascular Surgery 01/2004; 38(6):1390-5. · 2.88 Impact Factor
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    ABSTRACT: In this paper, a new system for real time contour tracking is presented. If a rough contour of the desired structure is available on the first image of a sequence, the system can automatically outline the contours on the subsequent images at video rate. The method we used is based on a new edge detector which was obtained by the generalization of the first order absolute central moment operator. The new algorithm proved to be very robust to noise and fast enough to be implemented in real time. The contour tracking procedure was implemented on an integrated software/hardware platform composed of a personal computer equipped with a digital signal processing board. The system can capture an analog video signal with a resolution of 512×512 pixels, 25 frames/s, process the data and display the results in real time. A graphical user interface is also available to interact with the system. Tests on images of the descending thoracic aorta and of a carotid, recorded by echocardiography, are reported. The cross-sectional area of the aorta and the diameter of the carotid were computed in real time and plotted on the user interface. The system proved to be a useful tool for the investigation of vascular mechanisms.
    Real-Time Imaging. 01/2004;
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    M. Paterni, F. Faita, A. Benassi, M. Demi
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    ABSTRACT: Echographic imaging plays a decisive role in diagnostics. However, the narrow field of view which is obtainable with an ultrasound probe can be a serious drawback. Techniques are needed to extend the field of view by reconstructing panoramic images from image sequences. In this paper the results obtained with the algorithm developed by H. Bulthof et al. are illustrated. The algorithm was used to estimate the motion of the probe between every pair of consecutive frames of echographic sequences. Subsequently, the gray level map of every single frame of the sequence was translated according to the estimated motion and added to the gray level maps of the previous frames with a mean operation. Three kinds of test sequences were used to evaluate the algorithm performances: simulated sequences, sequences of a calibration phantom and sequences of brachial arteries.
    Computers in Cardiology, 2003; 10/2003
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    ABSTRACT: 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.
    Journal of Human Hypertension 05/2003; 17(4):253-63. · 2.82 Impact Factor
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    European Journal of Echocardiography - EUR J ECHOCARDIOGR. 01/2003; 4.
  • Microvascular Research 12/2002; 64(3):482-5. · 2.93 Impact Factor
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    ABSTRACT: Today most commercial equipment already provides ECG signals in a digital form and allow their registration in a local archive. However, the recovery of past ECGs from graph paper is still needed since ECGs are a valuable source of information regarding the clinical history of a patient and, consequently, it is very useful to have all the ECG recordings of the same patient in the same digital archive for subsequent analyses and comparisons. In this paper we propose a new method to convert ECGs from graph paper to digital signals. First a digital image of the ECG on graph paper is obtained with a flatbed scanner (600 dpi) and then a line detection procedure is used to detect and locate the ECG trace. The first order absolute moment (FOAM) is used as a mathematical operator to highlight the ECG trace with a ridge and the ECG signal is subsequently located at the top of the ridge with a multi-resolution approach.
    Computers in Cardiology, 2002; 10/2002
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    ABSTRACT: Quantitative myocardial contrast echocardiography was performed with harmonic power Doppler analysis using the background subtraction and Levovist (Schering AG, Berlin, Germany) as contrast agent in a triggered modality. Quantitative analysis of echocontrast was performed offline with PC software, obtaining the transit curves of microbubbles through the coronary capillary system. Coronary microcirculation in athletes showed a behavior substantially comparable with control participants, although at a higher level. Training determines a physiologic left ventricular hypertrophy that counterbalances the dilatation in the left ventricular chambers because of the higher blood volume in athletes compared with control participants. Angiogenesis and several functional adaptations (relaxation of small coronary arteries, increased production of nitric oxide by the coronary endothelium, or both), represent the potential mechanisms that allow an optimal distribution of oxygen and of substrates to the hypertrophied myocardium of the athletes.
    Journal of the American Society of Echocardiography 08/2002; 15(7):678-85. · 4.28 Impact Factor
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    ABSTRACT: 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. 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. 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.
    European Heart Journal – Cardiovascular Imaging 07/2002; 3(2):117-27. · 2.39 Impact Factor
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    ABSTRACT: 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). To evaluate the potential of a videodensitometric approach in assessing transmural ultrasonic tissue changes in HCM during dipyridamole infusion. 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). 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). 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.
    The International Journal of Cardiovascular Imaging 08/2001; 17(4):245-52. · 2.65 Impact Factor
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    ABSTRACT: 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.
    Italian heart journal: official journal of the Italian Federation of Cardiology 06/2001; 2(5):333-43.

Publication Stats

566 Citations
202.56 Total Impact Points

Institutions

  • 1991–2003
    • Università di Pisa
      • • Department of Clinical and Experimental Medicine
      • • Department of Information Engineering
      Pisa, Tuscany, Italy
  • 1997–2002
    • National Research Council
      • Institute of Clinical Physiology IFC
      Roma, Latium, Italy