Doppler Imaging Techniques Research Articles

Dynamical evolution of titanium, strontium, and yttrium spots on the surface of the HgMn star HD 11753

Aims. We gathered about 100 high-resolution spectra of three typical HgMn (mercury-manganese) stars, HD 11753, HD 53244, and HD 221507, to search for slowly pulsating B-like pulsations and surface inhomogeneous distribution of various chemical elements. Methods. Classical frequency analysis methods were used to detect line profile variability and to determine the variation period. Doppler imaging reconstruction was performed to obtain abundance maps of chemical elements on the stellar surface. Results. For HD 11753, which is the star with the most pronounced variability, distinct spectral line profile changes were detected for Ti, Sr, Y, Zr, and Hg, whereas for HD 53244 and HD 221507 the most variable line profiles belong to the elements Hg and Y, respectively. We derived rotation periods for all three stars from the variations of radial velocities and equivalent widths of spectral lines belonging to inhomogeneously distributed elements: P_rot (HD 11753)=9.54 d, P_rot (HD 53244)=6.16 d, and P_rot (HD 221507)=1.93 d. For HD 11753 the Doppler imaging technique was applied to derive the distribution of the most variable elements Ti, Sr, and Y using two datasets separated by ~65 days. Results of Doppler imaging reconstruction revealed noticeable changes in the surface distributions of TiII, SrII, and YII between the datasets, indicating the hitherto not well understood physical processes in stars with radiative envelopes that cause a rather fast dynamical chemical spot evolution.

Surface structure of the CoRoT CP2 target star HD 50773

We compare surface maps of the chemically peculiar star HD 50773 produced with a Bayesian technique and based on high quality CoRoT photometry with those derived from rotation phase resolved spectropolarimetry. The goal is to investigate the correlation of surface brightness with surface chemical abundance distribution and the stellar magnetic field. The rotational period of the star was determined from a nearly 60 day long continuous light curve obtained during the initial run of CoRoT. Using a Bayesian approach to star-spot modelling, which in this work is applied for the first time for the photometric mapping of a CP star, we derived longitudes, latitudes and radii of four different spot areas. Additional parameters like stellar inclination and the spot's intensities were also determined. The CoRoT observations triggered an extensive ground-based spectroscopic and spectropolarimetric observing campaign and enabled us to obtain 19 different high resolution spectra in Stokes parameters I and V with NARVAL, ESPaDOnS, and SemelPol spectropolarimeters. Doppler and Magnetic Doppler imaging techniques allowed us to derive the magnetic field geometry of the star and the surface abundance distributions of Mg, Si, Ca, Ti, Cr, Fe, Ni, Y, and Cu. We find a dominant dipolar structure of the surface magnetic field. The CoRoT light curve variations and abundances of most elements mapped are correlated with the aforementioned geometry: Cr, Fe, and Si are enhanced around the magnetic poles and coincide with the bright regions on the surface of HD 50773 as predicted by our light curve synthesis and confirmed by photometric imaging.

Response to: Comparison of laser Doppler imaging, fingertip lacticemy test, and nailfold capillaroscopy for assessment of digital microcirculation in systemic sclerosis

We read with interest the article by Correa and colleagues [1] in a recent issue of Arthritis Research & Therapy: 'Comparison of laser Doppler imaging, fingertip lacticemy test, and nailfold capillaroscopy for assessment of digital microcirculation in systemic sclerosis'. Using the laser Doppler imaging (LDI) technique, the authors found lower digital blood flow in systemic sclerosis (SSc) patients when compared with healthy controls. However, the authors did not discover any correlation between the functional (LDI) and morphological microvascular abnormalities, evaluated by nailfold capillaroscopy (NFC), suggesting that these techniques are complementary tools for the evaluation of independent microangiopathy aspects in SSc patients. The conclusions of the article may be controversial since these findings are in contrast with those of other recent reports that were not reported and considered in the authors' investigation. In particular, some recent studies described a correlation between fingertip blood perfusion (FBP), evaluated separately by LDI and laser Doppler flowmetry (LDF) techniques, and the extent of nailfold microvascular damage, as evaluated by nailfold videocapillaroscopy (NVC) [2-4]. The paper from Cutolo and colleagues [2] demonstrated a significantly lower FBP in SSc patients (P < 0.05) com-pared with controls, and this FBP was found to be partially reversible (increasing) after heating of the LDF probe at 36°C (P < 0.001), even if the slope of variation was significantly lower in SSc patients compared with controls (P < 0.05). Interestingly, SSc patients showing the 'late' NVC pattern of microangiopathy showed an FBP that was significantly lower than that of patients with the 'active' or 'early' NVC patterns (P < 0.05) [2,5]. In addition, a negative correlation between the FBP degree and the NVC rating (score) of the microvascular damage was observed (P < 0.05) [2,6,7]. Similar results were found by Rosato and colleagues [3], who described significantly lower mean blood perfusion in the hand/fingers of SSc patients characterized by the 'late' NVC pattern of microangiopathy when compared with patients showing the 'early' or 'active' NVC patterns. The authors concluded that the LDI and capillaroscopic images fully matched the definition of the various stages of the microvascular digital damage in SSc [3]. In the third study, again, SSc patients characterized by the 'active' or 'late' NVC patterns showed a red blood cell velocity that was more decreased (65.5% and 66.2% reduction, respectively) than that of patients sharing the 'early' pattern of microangiopathy [4]. This reduced red blood cell velocity was significantly associated with selected NVC morphological parameters, including capillary ramification and capillary loss that characterize the advanced microvascular damage (P < 0.01) [4]. In recent years, the morphological features identifying the SSc microvascular damage progression have been recognized. Consequently, microvascular lesions detected by NVC in patients with SSc have been classified according to the three different NVC patterns mentioned above (namely, 'early', 'active', and 'late'), which are clearly distinguishable from the 'normal' nailfold capillaroscopic pattern [5,8]. The 'early' pattern is characterized by the presence of a small number of giant capillaries and capillary micro-hemorrhages, no evident loss of capillaries, and relatively well-preserved capillary distribution. If the vascular disease progresses, an 'active' SSc pattern becomes evident: giant capillaries and capillary microhemorrhages increase and there is moderate loss of capillary, whereas ramified capillaries are absent or mildly branched and the capillary architecture is mildly disorganized. Finally, the 'late' SSc pattern becomes manifest in the more advanced stage of the vascular disease. This latter pattern is characterized by the absence of giant capillaries and microhemorrhages but shares severe loss of capillaries and the development of extensive avascular areas, together with ramified and bushy capillaries (indicative of neoangiogenesis) [5,8]. As a matter of fact, the different nailfold microvascular abnormalities are not all present at the same time but are expressed in a dynamic manner during the progression of the SSc microangiopathy [9]. For these reasons, when searching in SSc patients for a possible link between digital blood flow and nailfold capillary abnormalities without considering the dynamic evolution of these morphological markers, a lack of correlation may be expected. Obviously, further studies are needed to better understand whether the morphological nailfold capillary abnormalities are the cause or the effect (or both) of digital blood hypoperfusion in patients with SSc.

Response to: Comparison of laser Doppler imaging, fingertip lacticemy test, and nailfold capillaroscopy for assessment of digital microcirculation in systemic sclerosis - authors' reply

We thank Sulli and colleagues [1] for their interest in our article entitled ‘Comparison of laser Doppler imaging, fi ngertip lacticemy test, and nailfold capillaroscopy for assess ment of digital microcirculation in systemic sclerosis’ [2], which was published in a recent issue of Arthritis Research & Th erapy. Sulli and colleagues commented on our results regarding the lack of correlation between the laser Doppler imaging (LDI) technique and nailfold capillaroscopy (NFC) and raised interesting questions. We totally agree with the comment that NFC is a powerful tool for the assessment of microvascular damage in systemic sclerosis (SSc). Recently, we showed a positive correlation between NFC abnormalities and the extent of cutaneous and visceral involvement in SSc patients, confi rming that NFC is a relevant approach not only for diagnosis but also for the evaluation of the extension and severity of SSc [3]. However, NFC evaluates only the morphological aspect of SSc vasculopathy, and complementary tools are used, with diff erent results, in many studies for the evaluation of functional aspects of peripheral vascular disease [4]. Sulli and colleagues mentioned three interesting, recently published papers [5-7] with results diff erent from those of our paper. However, diff erent methods for the evaluation of blood perfusion were used in each of them, and it is diffi cult to compare results obtained with diff erent techniques. Cutolo and colleagues [5] assessed fi ngertip blood perfusion by laser Doppler fl owmetry, and Mugii and colleagues [6] evaluated red blood cell velocity by means of videocapillaroscopy. We emphasize that only Rosato and colleagues [7], who were considered in our original paper, evaluated blood perfusion by means of LDI. Moreover, the mechanisms involved in SSc vasculopathy are complex, and controversial fi ndings are not surprising. Th e LDI method used in our original study is considered the most promising tool for the study of microvascular blood fl ow. In our study, LDI showed lower digital blood fl ow in SSc patients when compared with healthy controls and correlated negatively with fi ngertip lacticemy, allowing objective measurement of blood perfusion. It is also relevant to point out that Murray and colleagues [4] showed only a weak correlation between intercapillary distance measured by NFC and the blood fl ow also measured by LDI. As in our study, the authors could not fi nd any other correlation between other NFC parameters and LDI. Th erefore, it is appropriate to consider that diff erent techniques such as LDI (dynamic changes) and NFC (morph ology changes) complement one another. Of course, further studies with a larger sample of patients assessed by the same technique are required to evaluate possible discrepancies between diff erent studies.

Speckle tracking echocardiography: A new approach to myocardial function

Echocardiography is the most common diagnostic method for assessing cardiac function but some limitations affect this technique. Until now, visual assessment of wall motion and thickening has allowed only a subjective evaluation of myocardial function and requires long-term training. Recently, new echocardiographic techniques have been introduced to evaluate myocardial mechanics. Tissue Doppler imaging (TDI) technique is limited by angle-dependency such that only deformation along the ultrasound beam can be derived from velocities, while myocardium deforms simultaneously in three dimensions. Speckle tracking echocardiography (STE) is a more recent technique that provides a global approach to left ventricular myocardial mechanics, giving information about the three spatial dimensions of cardiac deformation. In this editorial, we describe the physical and pathophysiological concepts of STE, discussing the differences compared to TDI and underlining the pitfalls of this new technique.

Color Doppler Echocardiographic Assessment of Valvular Regurgitation in Normal Infants

Despite valvular regurgitation being a common finding in children, its prevalence in infants is unclear. The aim of this study was to determine the presence and severity of valvular regurgitation in normal infants using echocardiographic screening. Two-dimensional (2D) color Doppler echocardiography was performed on 420 consecutive infants (aged 1-12 months) with structurally normal hearts. Pulsed, continuous-wave, and color Doppler imaging techniques were used to detect and evaluate regurgitant blood flow at each valve. Valvular regurgitation was present in 258 infants (61.4%). Among these, 41 (15.9%) were found to have a heart murmur. Tricuspid regurgitation was found in 237 (56.4%) infants, pulmonary regurgitation in 71 (16.9%), mitral regurgitation in 51 (12.1%), and aortic regurgitation in nine (2.1%). Regurgitation of one valve occurred in 161 (38.3%) infants, of two valves in 84 (20%), and of three valves in 13 (3.1%). Right-sided regurgitation was significantly more common than left-sided regurgitation (p < 0.05). The degree of regurgitation was trivial or mild in 97.3% of infants and the peak velocities of the regurgitant jets were < or = 2.5 m/sec in all the valves, by Doppler echocardiography. The prevalence of inaudible valvular regurgitation is high in infants with structurally normal hearts. Multiple-valve involvement with regurgitation is not uncommon. Mild severity and low velocity on color Doppler, and the structural information provided by 2D imaging strongly suggest that these regurgitant flows are physiologically normal in infancy.

Correlation of ST-segment “hump sign” during exercise testing with impaired diastolic function of the left ventricle

Background The appearance of a discrete upward deflection of the ST segment, termed the ST hump sign during exercise testing has been associated with resting hypertension and exaggerated blood pressure response to exercise. Objective We investigated the correlation between the presence of hump sign during exercise testing with coexisting impaired diastolic function of the left ventricle (LV) at these patients. Methods We formed a cohort of 237 nonconsecutive patients (140 males, 41 ± 5 years old) having undergone a treadmill test, according to the Bruce protocol, which divided into 2 groups: group A, including 130 patients which presented ST-segment hump sign at any of the leads of the electrocardiograms recorded during exercise, and group B, including 107 patients that didn't. All patients subsequently underwent an echocardiographic estimation of the LV diastolic function, using conventional and Tissue Doppler Imaging techniques. Results From 237 patients included in our study, 106 had echocardiographic signs of diastolic LV dysfunction. Among them, the appearance of ST hump sign at the peak of exercise testing was observed in 93 patients (88%), particularly in the inferior and lateral leads, while no ST hump sign was observed only in 13 patients (12%) with impaired diastolic LV function. Conclusions The appearance of ST segment hump sign during exercise testing is strongly correlated with diastolic LV dysfunction and can be used as an exercise electrocardiographic index of diastolic LV dysfunction, independently from the echocardiographic study.

Exercise intolerance in patients with congenitally corrected transposition of the great arteries relates to right ventricular filling pressures

Patients with congenitally corrected transposition of the great arteries (ccTGA) have significantly reduced exercise tolerance. Progressive right ventricular (RV) dysfunction with tricuspid regurgitation (TR) and other haemodynamic lesions are common among them. We hypothesised that interaction of these factors may result in increased systemic RV filling pressure, which in turn impact on exercise capacity. Patients with ccTGA in functional class I or II, able to perform treadmill exercise and without resting cyanosis were enrolled. All patients underwent cardiopulmonary exercise testing and transthoracic echocardiographic examination. RV filling pressure was estimated using tissue Doppler imaging (TDI) techniques by measuring early annular diastolic velocity (Ea) and the ratio of the transtricuspid inflow to the early annular diastolic velocity (E/Ea). A total of 27 patients (mean age 41 years, 48% female) were assessed, the majority (63%) asymptomatic. Many patients had coexistent haemodynamic lesions including shunts, pulmonary stenosis, TR and systemic ventricular dysfunction. Average percentage predicted peak oxygen consumption, VE/VCO(2) slope and heart rate reserve were abnormal in this population. Patients with moderately/severely impaired exercise capacity (≤ 60% predicted peak VO(2)) had significantly higher E/Ea ratios compared to those with normal/mildly impaired exercise capacity (septal E/Ea = 17.1 ± 9.7 vs 8.8 ± 1.6 and lateral E/Ea = 11.5 ± 5.8 vs 6.6 ± 1.3, p = 0.007 and 0.01 respectively). Reduced exercise capacity is common in adults with ccTGA even among asymptomatic patients and relates to increased RV filling pressures assessed by TDI. This index could potentially be used to optimize therapy or prognosticate adverse events in ccTGA patients.

RS CVn binary IM Peg – investigation of stellar activity and surface flows

AbstractWe have obtained high resolution, high S/N spectra of the RS CVn binary IM Peg using UVES spectrograph at Kueyen 8.2m telescope of ESO VLT. We use Doppler imaging techniques to obtain stellar surface temperature maps from the UVES data. The TempMap code allows us to use surface differential rotation as an input parameter and thus to try to construct the rotation pattern on the stellar surface as part of the inversion process. The UVES observations are combined with spectroscopic observations from another time period obtained at the STELLA observatory. We obtain stellar surface temperature maps also from these spectra. These Doppler images are used to study the magnetic activity and surface differential rotation on IM Peg.

THE ANTIOXIDANT CEREBRALCARE GRANULE ATTENUATES CEREBRAL MICROCIRCULATORY DISTURBANCE DURING ISCHEMIA-REPERFUSION INJURY

Cerebralcare Granule (CG) is a compound Chinese medicine used for treatment of headache and dizziness associated with cerebrovascular diseases. To clarify the mechanism underlying the clinical outcome of CG, this study investigated the effects of CG on the structure and function of cerebral microvasculature during I/R injury. A total of 138 Mongolian gerbils were included and divided into four groups, each composed of 36 or 30 animals, for evaluating various parameters of concern. A skull window was prepared for microcirculatory observation in animals, which were subjected to I/R with or without pretreatment with CG (0.4 or 0.8 g/kg). The velocity of red blood cells in the venules was observed by a high-speed video camera system, along with intravital confocal microscopic measurements of microvascular diameters, adherent leukocytes, and albumin leakage in the brain cortex. Changes in the fluorescence intensity of dihydrorhodamine 123 in cerebral microvessels and malondialdehyde level in the cortex were measured. The ultrastructure of the microvessels in the cerebral cortex was analyzed using both transmission and scanning electron microscopy. In addition, cerebral blood flow was monitored using the laser Doppler imaging technique. Pretreatment with CG (0.4 or 0.8 g/kg) significantly alleviated I/R injury-induced disorders in cerebral microvasculature, as evidenced by the data observed at 60 min of reperfusion wherein the values in CG (0.4 g/kg) pretreatment group, CG (0.8 g/kg) pretreatment group, and I/R group were 2.43 ± 0.24, 2.28 ± 0.18, and 6.00 ± 0.35 for leukocyte adhesion, 2.51 ± 0.40, 2.33 ± 0.29, and 4.77 ± 0.24 for albumin leakage, 7.06 ± 0.81, 5.93 ± 0.42, and 28.38 ± 2.70 for dihydrorhodamine 123 fluorescence intensity in cerebral microvessels, 16.35 ± 0.52, 14.34 ± 0.68, and 21.46 ± 0.71 for malondialdehyde level in the cortex, and 0.43 ± 0.07, 0.46 ± 0.02, and 0.17 ± 0.08 for cerebral blood flow, respectively. I/R injury-elicited ultrastructural alterations in microvessels in cerebral cortex were also mitigated impressively by CG administration, manifested as attenuation of the reduced number of opening capillaries and the altered fine structures in endothelium, which were characterized by rough inner surface, increased intracellular vesicles, hypertrophy of digitations of intercellular contact, and swollen perivascular astroglial processes. Cerebralcare Granule is able to attenuate I/R injury-induced functional and structural changes in microvessels in the cerebral cortex of gerbils, an ability that is most likely correlated with its antioxidant potential. ABBREVIATIONS-DHR-dihydrorhodamine 123; ROS-reactive oxygen species; RBC-red blood cell; H2O2-hydrogen peroxide; FITC-fluorescein isothiocyanate; MDA-malondialdehyde; CBF-cerebral blood flow; O2−-superoxide anion; I/R-ischemia and reperfusion

The gold standard for noninvasive imaging in congenital heart disease: echocardiography

Echocardiography in pediatric and congenital heart disease is a key diagnostic technique in patients with congenital heart disease. Due to new technological developments, it has become a rapidly evolving field. In this review, we focus on recent developments in standardization and validation of standard techniques in pediatric and congenital echocardiography. This is mainly related to standardization of image acquisition and normalization of measurements for body size. The rest of the review is focused on the application of three-dimensional echocardiography, tissue Doppler imaging and Speqle tracking techniques to pediatric heart disease. New developments in standardization of echocardiography, the introduction of three-dimensional echocardiography and new functional techniques such as tissue Doppler and Speqle tracking strengthen the position of pediatric echocardiography as the most important diagnostic tool for patients with congenital heart disease.

Evaluation of Left Atrial Appendage Functions According to Different Etiologies of Atrial Fibrillation with a Tissue Doppler Imaging Technique by Using Transesophageal Echocardiography

Atrial fibrillation (AF) occurs due to various etiologies that carry different risks for thromboembolism. However, the effect of different etiologies on left atrial appendage (LAA) function has not been investigated. This study aimed to examine the LAA function in AF that occurred under various etiologies and to compare the findings with a novel tissue Doppler imaging (TDI) technique by using transesophageal echocardiography (TEE). LAA function was assessed in 84 patients with permanent AF according to various etiologies [mitral stenosis in 20 (24%), hypertension in 44 (52%), and hyperthyroidism in 20 (24%) patients] and in 23 controls with sinus rhythm. LAA area change, PW-Doppler and tissue velocities of LAA were measured. The presence of SEC or thrombus and their relation to LAA function was evaluated. LAA velocities were lowest in mitral stenosis and highest in hyperthyroidism. Moderate-severe LAA SEC was detected in 61 and thrombi in 23 patients. Factors associated with the severity of SEC were the percentage of the LAA area change, PW-Doppler peak emptying velocity, and TDI septal wall downward velocity. The percent of the LAA area change and PW-Doppler peak emptying velocity were the significantly related factors for the presence of thrombi (OR = 0.84, 95% CI = 0.74-0.95, P = 0.005 and OR = 0.85, 95% CI = 0.74-0.98, P = 0.02, respectively). LAA function deteriorated most severely in mitral stenosis and least in hyperthyroidism. The LAA area change and PW-Doppler emptying velocity were important predictors for SEC or thrombi. Although TDI was not superior to classical methods, it provided complementary data to PW-Doppler velocities for predicting SEC and thrombi.

First measurement of the magnetic field on FK Com and its relation to the contemporaneous star-spot locations

In this study, we present simultaneous low-resolution longitudinal magnetic field measurements and high-resolution spectroscopic observations of the cool single giant FK Com. The variation of the magnetic field over the rotational period of 2.4 d is compared with the star-spot location obtained using Doppler imaging techniques, V-band photometry and V − I colours. The chromospheric activity is studied simultaneously with the photospheric activity using high-resolution observations of the Hα ,H β and Hγ line profiles. Both the maximum (272 ± 24 G) and minimum (60 ± 17 G) in the mean longitudinal magnetic field, � Bz� , are detected close to the phases where cool spots appear on the stellar surface. A possible explanation for such a behaviour is that the active regions at the two longitudes separated by 0.2 in phase have opposite polarities.

Doppler imaging

In this paper, I present a short review of the history and modern status of Doppler imaging techniques, highlighting their dependence on the knowledge of the fundamental stellar parameters, the quality of stellar atmospheric models and the accuracy of spectral synthesis.

The Antioxidant Cerebralcare Granule® Attenuates Cerebral Microcirculatory Disturbance During Ischemia-Reperfusion Injury

Cerebralcare Granule (CG) is a compound Chinese medicine used for treatment of headache and dizziness associated with cerebrovascular diseases. To clarify the mechanism underlying the clinical outcome of CG, this study investigated the effects of CG on the structure and function of cerebral microvasculature during I/R injury. A total of 138 Mongolian gerbils were included and divided into four groups, each composed of 36 or 30 animals, for evaluating various parameters of concern. A skull window was prepared for microcirculatory observation in animals, which were subjected to I/R with or without pretreatment with CG (0.4 or 0.8 g/kg). The velocity of red blood cells in the venules was observed by a high-speed video camera system, along with intravital confocal microscopic measurements of microvascular diameters, adherent leukocytes, and albumin leakage in the brain cortex. Changes in the fluorescence intensity of dihydrorhodamine 123 in cerebral microvessels and malondialdehyde level in the cortex were measured. The ultrastructure of the microvessels in the cerebral cortex was analyzed using both transmission and scanning electron microscopy. In addition, cerebral blood flow was monitored using the laser Doppler imaging technique. Pretreatment with CG (0.4 or 0.8 g/kg) significantly alleviated I/R injury-induced disorders in cerebral microvasculature, as evidenced by the data observed at 60 min of reperfusion wherein the values in CG (0.4 g/kg) pretreatment group, CG (0.8 g/kg) pretreatment group, and I/R group were 2.43 +/- 0.24, 2.28 +/- 0.18, and 6.00 +/- 0.35 for leukocyte adhesion, 2.51 +/- 0.40, 2.33 +/- 0.29, and 4.77 +/- 0.24 for albumin leakage, 7.06 +/- 0.81, 5.93 +/- 0.42, and 28.38 +/- 2.70 for dihydrorhodamine 123 fluorescence intensity in cerebral microvessels, 16.35 +/- 0.52, 14.34 +/- 0.68, and 21.46 +/- 0.71 for malondialdehyde level in the cortex, and 0.43 +/- 0.07, 0.46 +/- 0.02, and 0.17 +/- 0.08 for cerebral blood flow, respectively. I/R injury-elicited ultrastructural alterations in microvessels in cerebral cortex were also mitigated impressively by CG administration, manifested as attenuation of the reduced number of opening capillaries and the altered fine structures in endothelium, which were characterized by rough inner surface, increased intracellular vesicles, hypertrophy of digitations of intercellular contact, and swollen perivascular astroglial processes. Cerebralcare Granule is able to attenuate I/R injury-induced functional and structural changes in microvessels in the cerebral cortex of gerbils, an ability that is most likely correlated with its antioxidant potential.

Systolic and diastolic function in patients with systemic sclerosis

Background Clinical and epidemiological findings indicate that symptomatic heart disease in patients with systemic sclerosis (SSc) predicts poor prognosis, but cardiac involvement may occur years before clinical manifestation. The aim of this study was to evaluate the cardiac function in patients with SSc and to correlate the echocardiographic parameters with others that quantify the diseases' severity. Methods Twenty consecutive patients with SSc were investigated with transthoracic echocardiography (TTE). Two dimensional, pulsed Doppler and pulsed tissue Doppler imaging (TDI) techniques were used, in all the patients, to assess the systolic and diastolic function for left ventricle (LV). Correlations were made between echocardiographic measurements and some clinical and serological features of the patients. Results None of the patients had any clinical signs of cardiac involvement, nor ECG or TTE systolic function impairment; there are significant differences between systemic sclerosis patients and control group for peak A velocity (0.75 ± 0.22 vs 0.57 ± 0.32, P = 0.05), E/ A ratio (1.14 ± 0.22 vs 1.48 ± 0.26, P = 0.01), E/Ea ratio (8.25 ± 1.57 vs 7 ± 2.2, P = 0.05), which account for filling impairment of LV. There are also significant correlations between some other parameters, like the mean duration of Raynaud's phenomenon and E/Ea ratio ( r = 0.48, P < 0.05). Conclusions The analysis of SSc heart disease, mainly at a preclinical level, is important in all the cases as an asymptomatic patient may have diastolic dysfunction which can be treated and should be closely observed.

Detection of Diastolic Abnormality by Dyssynchrony Imaging Correlation With Coronary Artery Disease in Patients Presenting With Visibly Normal Wall Motion

Post-systolic shortening (PSS) is a sensitive indicator of myocardial ischemia. We have developed a tissue Doppler imaging technique that portrays PSS, and whether PSS correlates with coronary artery disease (CAD) was investigated in 186 patients presenting with chest pain and normal echocardiograms. Delays of the displacement peaks from end-systole were calculated in the apical views and displayed from green (0 ms) to red (>or=100 ms): detection of diastolic abnormality by dyssynchrony imaging (DADI). CAD was judged positive by DADI when the left ventricular segments were color-coded red. Patients subsequently underwent thallium-201 myocardial perfusion single-photon emission computed tomography (n=150), coronary angiography (CAG, n=74), or both (n=37). CAD(-) was defined as negative scintigraphy test and/or no significant coronary artery stenosis by CAG. In 43 patients (23%), CAD(+) was confirmed by CAG as >75% diameter stenosis. DADI predicted CAD with sensitivity of 60%, specificity of 75%, predictive accuracy of 72%, positive predictive value of 42%, and negative predictive value of 86%. Among 74 patients who underwent CAG, sensitivity was best for the left anterior descending artery. DADI detected the regional diastolic abnormality, which correlated with the presence of CAD in patients presenting with visibly normal wall motion.

Noninvasive Techniques to Assess Myocardial Ischemia in Hypertensive Patients

Hypertensive patients are more affected by coronary artery disease (CAD) than normotensive patients. Currently, established techniques are able to diagnose myocardial ischemia/CAD in hypertensive patients with suspected CAD. An irrevocable role remains for exercise electrocardiogram (ECG) owing to the many parameters evaluated under physiologic conditions. However, the suboptimal specificity of a positive exercise ECG demands further examination of hypertensive patients with either myocardial single-photon emission computed tomography (SPECT) or stress echocardiography, both more specific than exercise ECG in diagnosing CAD. The high specificity of imaging techniques also makes them highly predictive of cardiac events. Additional techniques to help diagnose CAD are available. Tissue Doppler imaging, strain and other echo-derived techniques may add quantitative elements to recognize CAD in hypertensive hearts. The accuracy of MRI is improving to study myocardial function and perfusion. Positron emission tomography and multislice computed tomography, also in-built with fusion scanners, are playing roles in combining coronary angiography and myocardial function/ischemia assessment. However, no significant application of these additional techniques is available for hypertensive patients. Epicardial CAD assessed by coronary angiography remains the gold standard to decide for revascularization procedures. The presence of microcirculatory dysfunction, a symptom typical of hypertensive hearts, is opening up new areas of noninvasive diagnostic techniques for the detection of coronary flow reserve (CFR) and related myocardial ischemia. The quantification of CFR may render this parameter pivotal to deciding the need for revascularization procedures of intermediate coronary stenosis and it may become an additional gold standard in evaluating coronary vessels. Moreover, even with normal epicardial coronary arteries, microcirculation dysfunction bears prognostic stratification capabilities for hypertensive patients and it may become a promising therapeutic target in the near future.

Searching for a link between the presence of chemical spots on the surface of HgMn stars and their weak magnetic fields

AbstractWe present the results of mapping the HgMn star AR Aur using the Doppler Imaging technique for several elements and discuss the obtained distributions in the framework of a magnetic field topology.

Abstract 4228: Objective Judgment in Dobutamine Stress Echocardiography: Visualization of Post-Systolic Shortening by Tissue Doppler Imaging

Background: Although dobutamine stress echocardiography (DSE) is widely used for the detection of coronary artery disease (CAD), interpretation requires expertise. Post-systolic shortening (PSS) is a sensitive maker of myocardial ischemia. We have developed a novel tissue Doppler imaging (TDI) technique that readily visualizes the presence of PSS on 2-dimensional echocardiograms, and investigated whether CAD is objectively detectable by using this technique during DSE. Methods: Detection of diastolic abnormality by displacement Imaging (DADI): PSS was detected by using tissue Doppler displacement timing analysis. In this method, end-systole was automatically determined from tissue velocity, and delays of the displacement peaks from the end-systole were displayed from green to red on the left ventricular apical views, depending on the preset time window. DSE was performed in consecutive 51 patients prior to coronary angiography (CAG) who underwent diagnostic CAG for suspected CAD, and presented with normal LV wall motion at rest (male=31, age ranged 44 – 83 years). We measured the time from the end-systole to displacement peak (ΔT) at each segment in the apical, mid and basal segments by the standard apical plane (long axis, 4 chamber and 2 chamber views). The optimal cut-off value of ΔT for discriminating normal from CAD was determined by receiver operating characteristic analysis. Finally, DADI was performed using the optimal ΔT. CAD was confirmed by CAG as having &gt;75% diameter stenosis. Results: Angiographic CAD was present in 31 patients (61%). DADI predicted CAD with sensitivity of 87%, specificity of 75%, negative predictive value of 79%, and predictive accuracy of 82% at the cut-ff ΔT of 80 ms at peak DSE. Conclusion: DADI was useful in making objective judgment in DSE by readily portraying the presence of PSS, a marker of myocardial ischemia, on 2-dimensional echocardiograms in patients with inducible myocardial ischemia.