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T2-weighted short-tau inversion recovery (T2w-STIR) imaging is the best approach for oedema-weighted cardiac magnetic resonance imaging (MRI), as it suppresses the signal from flowing blood and from fat and enhances sensitivity to tissue fluid. The purpose of this pictorial review is to illustrate the clinical use and application of this technique in various ischaemic and non-ischaemic conditions. In ischaemic heart disease, T2w-STIR represents the technique of choice for detecting oedema in patients with acute myocardial infarction (MI), allowing discrimination of acute and chronic injuries. Myocardial haemorrhage may also be depicted as a region of signal abnormality characterised by a central hypointense core with a peripheral hyperintense rim, presumably reflecting the presence of intracellular methaemoglobin within the necrotic area. In the acute setting, elevated T2 relaxation times in association with regional contractile dysfunction but no signs of delayed enhancement may also signify a reversible ischaemic injury without necrosis. In acute myocarditis, the distribution pattern of T2w hyperintensity may be focal in approximately 30% of patients or diffuse in the remaining 70%, and myocardial oedema may be the only marker of disease. Tissue oedema may also be observed in various other conditions, such as primary cardiomyopathies (CMP), storage disease, pulmonary hypertension and cardiac transplant rejection. T2w-STIR represents an appealing and versatile technique that can be applied in a wide variety of ischaemic and non-ischaemic conditions, allowing detection of segmental or global increase of myocardial free water content, reflecting an acute myocardial injury.

Background: Experimental data show that the right ventricle (RV) is more resistant to ischemia than the left ventricle. To date, limited data are available in humans because of the difficulty of discriminating reversible from irreversible ischemic damage. We sought to characterize RV ischemic injury in patients with reperfused myocardial infarction using cardiovascular magnetic resonance., Methods and Results: In 3 tertiary centers, 242 consecutive patients with reperfused acute ST-segment elevation myocardial infarction were studied with cardiovascular magnetic resonance at 1 week and 4 months after myocardial infarction. T2-weighted and postcontrast cardiovascular magnetic resonance scans were used to depict myocardial edema and late gadolinium enhancement, respectively. Early after infarction, RV edema was common (51% of patients), often associated with late gadolinium enhancement (31% of patients). Remarkably, RV edema and late gadolinium enhancement were found in 33% and 12% of anterior left ventricular infarcts, respectively. Baseline regional and global RV functions were inversely related to the presence and extent of RV edema and RV late gadolinium enhancement. At follow-up, a significant decrease in frequency (25/242 patients; 10%) and extent of RV late gadolinium enhancement was observed (P<0.001). With the use of multivariable analysis, the presence of RV edema was an independent predictor of RV global function improvement during follow-up (β-coefficient=0.221, P=0.003)., Conclusions: Early postinfarction RV ischemic injury is common and is characterized by the presence of myocardial edema, late gadolinium enhancement, and functional abnormalities. RV injury is not limited to inferior infarcts but is commonly found in anterior infarcts as well. Cardiovascular magnetic resonance findings suggest reversibility of acute RV dysfunction with limited permanent myocardial damage at 4-month follow-up.

We report a case of a 3-year-old girl with a history of recurrent dysphagia and feeding difficulties. After chest x-ray and esophagogram examination, magnetic resonance imaging revealed the presence of a right-sided aortic arch with an aberrant retroesophageal left subclavian artery arising from a Kommerell diverticulum., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Background: Percutaneous coronary intervention (PCI) is a highly effective therapy for acute ST-elevation myocardial infarction. Adjunctive therapy with platelet glycoprotein (GP) IIb/IIIa inhibitor can result in increased vessel patency and improved outcomes in ST-elevation myocardial infarction patients undergoing PCI. The investigation of novel dosing and delivery strategies of this therapy may help to further improve outcomes., Methods: IC-Clearly is a randomized, open-label, multicenter trial, with the purpose of evaluating the effectiveness of an intracoronary bolus dose of abciximab delivered using the ClearWay RX catheter vs. an intravenous bolus of abciximab for ST-elevation myocardial infarction with angiographically visible thrombus (thrombus grade >or=2). A total of 150 patients will be randomized 1: 1 to treatment of the culprit artery with intracoronary abciximab (75 patients) or intravenous abciximab (75 patients) in addition to a maintenance infusion regimen of abciximab administered intravenously for 12 h after PCI. The number of patients included in this study is based on the estimation of sample size needed to identify a statistically significant difference in the primary endpoints between the two groups. The primary endpoint chosen to evaluate this hypothesis is infarct size assessed by cardiac magnetic resonance. Clinical outcomes will be assessed for each patient through hospital discharge and at 30-day follow-up., Conclusion: The purpose of this study is to evaluate whether an intracoronary bolus of abciximab delivered with the ClearWay RX catheter prior to the 12 h post-PCI intravenous infusion regimen of abciximab will result in significant additional clot resolution in vivo and improved myocardial perfusion when compared with an intravenous bolus of abciximab on top of the 12 h post-PCI intravenous infusion regimen of abciximab as per standard practice. The primary endpoint chosen to evaluate this hypothesis is infarct size as assessed by cardiac magnetic resonance.

Radiological reporting in chest computed tomography (CT) is primarily focused on assessing pulmonary and mediastinal abnormalities, thereby tending to overlook the heart. However, incidental cardiac abnormalities are often encountered and misdiagnosed, which may potentially impact the patient's treatment or necessitate further investigation. The aim of this pictorial review is to provide a stepwise approach to assessing the heart on routine non-electrocardiographic-gated (non-ECG-gated) chest CT and describing common and less frequent cardiac abnormalities.

Objectives: We investigated the extent and nature of myocardial damage by using cardiovascular magnetic resonance (CMR) in relation to different time-to-reperfusion intervals., Background: Previous studies evaluating the influence of time to reperfusion on infarct size (IS) and myocardial salvage in patients with ST-segment elevation myocardial infarction (STEMI) have yielded conflicting results., Methods: Seventy patients with STEMI successfully treated with primary percutaneous coronary intervention within 12 h from symptom onset underwent CMR 3 +/- 2 days after hospital admission. Patients were subcategorized into 4 time-to-reperfusion (symptom onset to balloon) quartiles: < or =90 min (group I, n = 19), >90 to 150 min (group II, n = 17), >150 to 360 min (group III, n = 17), and >360 min (group IV, n = 17). T2-weighted short tau inversion recovery and late gadolinium enhancement CMR were used to characterize reversible and irreversible myocardial injury (area at risk and IS, respectively); salvaged myocardium was defined as the normalized difference between extent of T2-weighted short tau inversion recovery and late gadolinium enhancement., Results: Shorter time-to-reperfusion (group I) was associated with smaller IS and microvascular obstruction and larger salvaged myocardium. Mean IS progressively increased overtime: 8% (group I), 11.7% (group II), 12.7% (group III), and 17.9% (group IV), p = 0.017; similarly, MVO was larger in patients reperfused later (0.5%, 1.5%, 3.7%, and 6.6%, respectively, p = 0.047). Accordingly, salvaged myocardium markedly decreased when reperfusion occurred >90 min of coronary occlusion (8.5%, 3.2%, 2.4%, and 2.1%, respectively, p = 0.004)., Conclusions: In patients with STEMI treated with primary percutaneous coronary intervention, time to reperfusion determines the extent of reversible and irreversible myocardial injury assessed by CMR. In particular, salvaged myocardium is markedly reduced when reperfusion occurs >90 min of coronary occlusion.

Background: The 64-slice multidetector-row computed tomography (MDCT) is an accurate noninvasive technique for assessing the degree of luminal narrowing in coronary arteries of patients with chronic ischemic disease. Aim of this study was to determine the value of MDCT in comparison to invasive coronary angiography (ICA) for detecting the presence and extent of coronary atherosclerotic plaques in a population of asymptomatic, hypertensive patients considered to be at high risk for cardiovascular events., Methods: We studied 67 asymptomatic, hypertensive patients at high-risk (Euro Score >5%). All patients had negative or nondiagnostic findings at exercise stress testing and therefore underwent both MDCT and ICA., Results: In the per-patient analysis, MDCT correctly identified 16/17 (94%) patients with significant coronary artery disease involving at least 1 vessel and 48/50 (96%) normal subjects. In the per-segment analysis, MDCT correctly detected 21/22 (95%) coronary segments with a stenosis >or=50% and 856/868 (98%) normal segments, with a high negative predictivity of normal scans (100%). There was a good concordance between MDCT and ICA, with a high Pearson correlation coefficient between the coronary narrowings with the two techniques (r=0.84, p<0.01). Mean coronary calcium score was higher for the 17 patients with significant coronary artery disease on ICA than in the 50 patients without (422+/-223 HU vs 72+/-21 HU p<0.001). The ROC curves identified 160 as the best calcium volumetric score cut-off value able to identify >or=1 significant coronary stenosis with sensitivity 88% and specificity 85%., Conclusions: MDCT is an excellent noninvasive technique for early identification of significant coronary stenoses in high risk asymptomatic hypertensive patients and might provide unique information for the screening of this broad population.

A comprehensive whole-body approach to noninvasive evaluation of coronary and extracoronary vasculature is currently not available. The objective of our study was to assess the potential of 64-slice computed tomography angiography (64-CTA) for whole-body evaluation of atherosclerosis burden. Seventy-eight patients referred for coronary imaging underwent whole-body 64-CTA using an adjusted strategy for the administration of contrast medium with dose-saving algorithms involving ECG modulation and reduced tube voltage. Arterial segments (15 coronary, 32 systemic) were evaluated for significant (> or =50%) steno-occlusive disease while arterovenous density was evaluated at seven extracoronary locations. Homogeneous attenuation (mean 321 +/- 20 HU) was obtained throughout the systemic vasculature. Atherosclerosis was observed in 238/995 (24%) coronary and 368/2441 (15%) systemic segments. Significant stenoses/occlusions were present in 214 (21%)/24 (2.5%) coronary segments while asymptomatic clinically relevant stenoses were present in 49 systemic segments. Sensitivity, specificity, positive and negative predictive values of coronary 64-CTA among 52 patients who also underwent quantitative coronary angiography were 92%, 95%, 81% and 98%, respectively. ECG modulation decreased radiation exposure to 14.1-15.4 mSv per patient. Comprehensive, noninvasive assessment of atherosclerosis can be performed by whole-body 64-CTA and may have a positive impact on secondary prevention.

The pericardium and pericardial diseases in particular have received, in contrast to other topics in the field of cardiology, relatively limited interest. Today, despite improved knowledge of pathophysiology of pericardial diseases and the availability of a wide spectrum of diagnostic tools, the diagnostic challenge remains. Not only the clinical presentation may be atypical, mimicking other cardiac, pulmonary or pleural diseases; in developed countries a shift for instance in the epidemiology of constrictive pericarditis has been noted. Accurate decision making is crucial taking into account the significant morbidity and mortality caused by complicated pericardial diseases, and the potential benefit of therapeutic interventions. Imaging herein has an important role, and cardiovascular magnetic resonance (CMR) is definitely one of the most versatile modalities to study the pericardium. It fuses excellent anatomic detail and tissue characterization with accurate evaluation of cardiac function and assessment of the haemodynamic consequences of pericardial constraint on cardiac filling. This review focuses on the current state of knowledge how CMR can be used to study the most common pericardial diseases.

Background and Objectives: Transplantation should favorably affect coronary calcification (CAC) progression in dialysis; however, changes in CAC score in the individual patient are not reliably evaluated., Design, Setting, Participants & Measurements: The authors used special tables of reproducibility limits for each score level to study, by multislice computed tomography and biochemistries, the 2-year changes in CAC in 41 transplant patients (age 48 +/- 13 yr, 25 men, dialysis vintage 4.8 +/- 4.3 yr, underwent transplant 6.2 +/- 5.5 yr prior). Thirty balanced dialysis patients served as controls., Results: In the study group, Agatston score was stable, and C-reactive protein decreased, whereas fetuin and osteoprotegerin increased. In the control group, Agatston score increased, parathyroid hormone and phosphate decreased, and inflammation markers were persistently twice as high as in the study group. With regard to individual changes, 12.2% transplant patients worsened, compared with 56.6% of patients in dialysis (P < 0.0001). Patients without calcification at entry showed slower progression in transplantation (8.3%) than in dialysis (44.4%; P < 0.034), and the difference was similar to that observed in cases with CAC (17.6% versus 61.9%; P < 0.007). Discriminant analysis indicated parathyroid hormone, the modality of therapy (dialysis or transplantation), and erythrocyte sedimentation rate as the variables most associated with worsening., Conclusions: Renal transplantation lowers but does not halt CAC progression. Inflammation and hyperparathyroidism are associated with progression in the populations studied.

Objectives: The purpose of this study was to evaluate the impact on myocardial perfusion and infarct size as assessed by contrast-enhanced magnetic resonance imaging (CE-MRI) of a manual thrombectomy device, Export Medtronic (EM) (Medtronic Inc., Minneapolis, Minnesota), as adjunctive therapy in primary percutaneous coronary intervention (PPCI) in a subset of patients with anterior ST-segment elevation myocardial infarction (STEMI)., Background: PPCI may cause thrombus dislodgment, leading to microvascular damage., Methods: One hundred seventy-five STEMI patients were randomly assigned to standard percutaneous coronary intervention (PCI) (n = 87) or EM-PCI (n = 88). The primary end points were the occurrence of myocardial blush grade > or =2 and the rate of 90-min ST-segment resolution >70%. The CE-MRI substudy was performed in 75 patients with anterior STEMI to assess microvascular obstruction and infarct size., Results: Myocardial blush grade > or =2 and ST-segment resolution occurred more frequently in the EM-PCI group (88% vs. 60%, p = 0.001; and 64% vs. 39%, p = 0.001). In the acute phase, microvascular obstruction extent was significantly lower in the EM-PCI group and at 3 months, infarct size was significantly reduced only in the EM-PCI group. A lower incidence of cardiac death in the EM-PCI group (4.6% vs. 0%, log-rank test p = 0.02) was observed at 9 months., Conclusions: Thrombectomy prevents thrombus embolization and preserves microvascular integrity reducing infarct size, and it therefore represents an useful adjunctive therapy in PPCI.

Objective: To evaluate dose reduction and image quality in coronary 64-slice multidetector computed tomography using an automatic exposure control system (AECs)., Methods: A total of 101 patients were divided into 4 groups. Tube current was 600 and 800 mAs in groups A and B and adapted at 600 and 800 quality-reference mAs using an AECs in groups C and D. Effective dose and organ-equivalent dose were evaluated. Image noise was quantified as standard deviation of air-space attenuation. Two observers assessed technical adequacy and image quality using a 4-point scale., Results: Effective dose ranged from 8.6 mSv (group C) to 15 mSv (group B) with significant dose reduction for examinations performed at 600 mAs (21.7%) and 800 mAs (29.4%). Contribution of organ-equivalent doses showed higher exposure for lungs (42%) and breast (22%). Noise was significantly higher in groups studied with AECs. Larger coronary segments resulted in higher image quality scores without differences between groups., Conclusion: Automatic exposure control systems provides images of diagnostic quality with substantial dose reduction.

Purpose: The aim of this study was to validate a 64-row multidetector computed tomography (64-MDCT) acquisition protocol with biphasic administration of contrast medium for comprehensive assessment of the coronary and systemic arterial tree in a single examination., Materials and Methods: The scanning protocol comprised two acquisitions: an electrocardiograph (ECG)-gated scan at the level of the heart, followed by a total-body, low-dose scan of the systemic arterial circulation. Twenty patients were evaluated using two different strategies for contrast administration. In ten patients, the delay between the two acquisitions was set at 40 s, whereas in the remaining patients, it varied between 45 s and 65 s. For both strategies, the degree of systemic arterial opacification and the attenuation gradient between arterial and venous structures were quantitatively assessed at six extracoronary locations. Two observers evaluated in consensus the presence or absence of atherosclerosis and the degree of stenosis of arterial segments., Results: Three hundred coronary segments were analysed. Arterial-wall changes were depicted in 155 (51%) segments, and in 35 (23%), the degree of stenosis was > 50%. Of the 640 extracoronary arterial segments, 250 (39%) presented atherosclerotic wall alterations, in 50 (20%), the degree of stenosis was > 50% and five were affected by aneurysmal dilatation. The magnitude of arterial opacification values and attenuation gradients between arterial and venous structures were significantly higher in patients scanned with the 40-s fixed-delay strategy., Conclusions: Whole-body CT angiography with biphasic administration of contrast agent and fixed scan delay has been shown to be a feasible and reproducible technique. Comprehensive data on the global atherosclerotic burden potentially offer important therapeutic options for subclinical, high-risk segments.

Background: The sequence of left ventricular (LV) systolic emptying is not completely understood. Using real-time 3-dimensional echocardiography, we investigated this sequence and LV synchronicity in physiological and pathological conditions., Methods and Results: The study population consisted of 116 healthy volunteers, 20 top-level athletes, 35 patients with LV dysfunction, and 84 patients with LV dysfunction and left bundle-branch block (LBBB). We subdivided the LV into 16 volumetric segments for regional analysis and into apical, middle, and basal regions to calculate the mean of end-systolic times and the time to minimum systolic volume of each region. In healthy volunteers and in top-level athletes, the emptying systolic times increased smoothly from apex to base. These differences determined an apex-to-base time gradient in the LV emptying sequence. In patients with LV dysfunction and without LBBB, this gradient was maintained with a relatively higher LV dyssynchrony. However, in patients with LV dysfunction and LBBB, there was no clear sequence in LV emptying volumes, and this group had the highest LV dyssynchrony., Conclusions: Real-time 3-dimensional echocardiography tomographic slicing of the LV enables accurate analysis of LV emptying in physiological conditions and in conditions of LV dysfunction with and without electrical dyssynchrony. Progressive dilation of LV produces deterioration in LV synchronicity. However, it is the presence of LV dysfunction in combination with LBBB that determines the loss of the apex-to-base time gradient in LV emptying.

The aim of our study has been to evaluate the ability of 64-slice computed tomographic angiography (CTA) to assess coronary artery stent patency, relative to selective coronary angiography (SCA). Fifty-five consecutive patients (age range 45-80 years) with 97 previously implanted coronary artery stents underwent 64-slice CTA. The 55 patients comprised 40 subjects (group A) who were referred for follow-up SCA at a mean interval of 9.6 months after stent positioning, and 15 subjects (group B) in whom SCA was clinically indicated. Stent evaluation was performed independently by two blinded readers in terms of image quality and presence of in-stent restenosis (ISR; lumen obstruction of >or=50%). SCA was performed in 41/55 patients; 14 patients refused to undergo SCA after the 64-slice CTA exam. A total of 88 stents in 74 segments were analyzed. Twenty-one of the 74 stented segments were of poor image quality and were not considered for further analysis. Sixty-four-slice CTA detected 12/16 ISR (sensitivity: 75%) and ruled out ISR in 32/37 cases (specificity: 86%). Sixty-four-slice CTA is a valuable modality for follow-up of coronary artery stent patency only in selected patients. Appropriate candidates for follow-up 64-slice CTA should be established based on stent diameter, stent material and type as well as HR and heart rhythm. However, given the number of non-assessable segments, further work would appear necessary before 64-slice CTA can be considered a suitable procedure for broad clinical application in the evaluation of coronary artery stent patency.

Radiation exposure is a critical issue in multidetector CT (MDCT) particularly since fast MDCT scanners have become widely available, and the method has been proposed as a noninvasive diagnostic tool for an increasing number of clinical applications. Additional features of MDCT imaging affecting individual dose are related to the inappropriate use of scanners caused by practices such as scanning beyond the area of interest or acquiring unnecessary multiphase image sets. In order to reduce individual exposure and in accordance with the ALARA principle, several strategies have been implemented over the last few years which are based on X-ray emission or optimization of scanning parameters (i.e. mAs, kV, pitch, collimation) or which take account of the individual patient's characteristics (automatic exposure control systems and ECG-pulsing techniques for ECG-gated acquisitions). These strategies allow optimization of image quality while keeping individual exposure at the lowest level. We review here these different strategies taking into account the relationship between image noise and different scanning parameters. Data from the literature are discussed, and current technological developments are considered, including initial results of dual source and SnapShot pulse technologies which have been shown to result in a significant dose reduction in ECG-gated cardiac acquisitions without compromising image quality.

Purpose: This study was performed to evaluate the ability of 64-slice multidetector computed tomography (MDCT) to detect previous myocardial infarctions (MIs) in patients referred for the assessment of the coronary arteries. In patients with regional changes of left ventricular wall myocardial density, the territory-dependent coronary vessel status was examined., Materials and Methods: We retrospectively assessed 202 consecutive patients referred for 64-slice MDCT of the coronary arteries. In all cases, detailed, clinical, serological and electrocardiograph (ECG) data were collected to identify patients with a previous diagnosis of MI. An initial qualitative evaluation of MDCT images was performed in all patients to identify areas of suspected myocardial necrosis, which were defined as regions of lower density within normally enhanced left ventricular myocardium. Thereafter, in all patients with suspected MIs, attenuation values and left ventricular wall thickness were also measured at the level of the normal myocardium and within the hypodense regions. Each MI was also assigned to the distribution territory of a coronary vessel, and morphological data were combined with MDCT angiographic findings., Results: After clinical assessment, MI was found in 27 patients (six acute).; 64-slice MDCT was able to detect the presence of MI in 24/27 cases, showing sensitivity and specificity of 89% and 95%, respectively, and an overall diagnostic accuracy of 95%. Quantitative analysis showed a significant difference (p<0.01) between attenuation values of normal vs. infarcted myocardium (124.5+/-19 HU vs. 56.1+/-23 HU, respectively); wall thinning was exclusively observed in chronic MIs (p<0.01). In 23/24 detected cases, analysis of territory-dependent arteries showed findings compatible with presence of MI., Conclusions: The presence of MI is well depicted with retrospective 64-slice MDCT. The main advantage of 64-slice MDCT is that it allows to evaluate and relate the status of a vessel and its dependent myocardial region in a single exam.

The ascidian Ciona intestinalis is a useful model for the study of nervous system development and function. The larva of this animal represents a 'primitive' vertebrate form that contains only about 100 neurons in the CNS. Although embryos can be easily subjected to genetic manipulation, the nervous system cells are not easily accessible for neurophysiological study at the larval stage. To remedy this problem, we have developed a method to obtain primary cell cultures from the larval stage of Ciona. Light microscopy and electrophysiology discriminate several types of cells including neurons and photoreceptors. The results show that in Ciona primary cultures different types of neurons as well as neurite sprouting and synapse formation can be visualised. Ciona primary cell cultures will be very useful to study the biochemical, molecular and biophysical properties of individual cells in the larval nervous system of C. intestinalis.

Purpose: We present our initial clinical experience with a recently introduced 64-detector computed tomography (64-MDCT) scanner that makes use of a periodic motion of the focal spot in the longitudinal direction (z-flying focal spot), which enables it to reach a final spatial resolution of 0.4 x 0.4 x 0.4 mm(3) and a temporal resolution of 83 ms., Materials and Methods: A total of 114 patients (108 men, six women; age range 36-77 years, mean 63.1 years) underwent retrospective electrocardiogram (ECG)-gated examination of the coronary arteries using a 64-MDCT scanner (Somatom Sensation 64, Siemens Medical Solutions, Germany). Acquisition parameters were the following: collimation 64 x 0.6 mm, 800 quality reference milliampere second (mAs), 120 kVp, 0.33-s gantry rotation time and pitch 0.2. Images were acquired in all cases after i.v. administration of 80 ml of contrast agent (Iomeron 400 mgI/dl, Bracco, Italy) + 30 ml of saline at 4 /s and delay time determined using a bolus triggering technique. Oral betablockers were administered to patients with heart rate (HR) >75 bpm. To reduce radiation exposure, an automatic exposure control system was applied in all cases to adapt tube current to patient size and anatomic shape (CARE Dose 4D, Siemens Medical Solutions, Germany). The optimal temporal window for raw data reconstruction was chosen from an initial preview of images reconstructed with different phase settings (range 0%-95% RR interval with 5% gap) at a selected anatomical level in the mid part of the right coronary artery. CT dose index volume and effective dose were quantified in all patients using dedicated software., Results: Mean HR recorded during image acquisition was 65.6+/-19.2 bmp (range: 44-96 bmp), and beta-blockers were administered to 16/114 patients (14.0%). Technical adequacy was achieved in all patients but two (2/114; 1.7%). In patients with HR <60 bmp, the best reconstruction intervals were identified in the end-systolic (30%-35% of the RR interval) and end-diastolic (60%-65% of the RR interval) phases; with faster HR (>80 bmp), high image quality was observed in end-systole (30%-35% of the RR interval). Mean CT dose index (CTDI) volume was 36.53+/-8.30 mGy per patient. In comparison with a conventional examination with fixed mAs, the use of the CARE Dose 4D system provided a 33.3% CTDI volume reduction (p<0.001). Mean effective dose was 9.5+/-3.4 millisievert (mSv) per patient (range 7.1-17.7)., Conclusions: The 64-MDCT scanner diagnostic performance for coronary CT angiography is further improved with better spatial and temporal resolution and faster scan times; besides, initial clinical results are promising. The use of dose-reducing acquisition techniques is mandatory to limit radiation exposure to the patient.

L- and D-aspartic acids (L-Asp and D-Asp) are present in the majority of nervous systems. In phylogeny, significant levels have been reported in mollusc brains, particularly cephalopods. To examine the role of L- and D-Asp on a cephalopod receptor, we studied ligand gating of a squid glutamate receptor (SqGluR) expressed in HEK 239 (human embryonic kidney) cells. Under voltage clamp, application of L-glutamate (L-Glu; 1-30 mM), but not D-glutamate (D-Glu), or L- or D-Asp, evoked an inward current of 0.1 nA. L- or D-Asp (200 microM) applied with 20 mM L-Glu, slowed the time course of activation and inactivation of the L-Glu gated current (time constant increased from 1 s (L-Glu alone) to 3 s (D-Asp and L-Glu) and to 19 s (L-Asp and L-Glu)). Our results suggest that in molluscan systems, aspartic acid could act as a neuromodulator during glutamatergic transmission and could significantly alter synaptic integration by slowing glutamate receptor gating.

Vascular calcifications in CKD are now linked to serum alterations of both divalent ions and calcification inhibitory proteins. Due to possible biochemical differences between dialysis (D) and transplantation (Tx), we examined the entity and severity of these biochemical modifications and of coronary artery calcium score separately in these two populations. We assayed, besides standard markers of inflammation, divalent ions and serum levels of fetuin, matrix Gla protein (MGP) and osteoprotegerin (OPG), in 51 Tx patients (age 45 +/- 12 years; 30 males, 21 females; previous D duration 4.8 +/- 4.2 years; Tx since 6.6 +/- 5.5 years; Cr 1.8 +/- 0.6 mg/dl) and in 49 D patients (age 49 +/- 14 years; 30 males,19 females; D duration 5.6 +/- 4.8 years). Additionally, coronary calcium score (AS) was evaluated by cardiac multi-slice CT. Compared with D patients, Tx patients had better values of divalent ions and inflammation markers, and lower prevalence (65 vs. 86%; p < 0.02) and severity (AS = 570 +/- 1,637 vs. 1,311 +/- 3,128; p < 0.008) of coronary calcification. In addition, a tendency toward normalization for all of the three calcification inhibitory proteins was evident. In both Tx and D, AS correlated with age and OPG (Tx: r(s) = 0.439, p < 0.001, and r(s) = 0.510, p < 0.0001; D: r(s) = 0.471, p < 0.001, and r(s) = 0.403, p < 0.005, respectively); in D patients, a correlation was present also with D duration (r(s) = 0.435; p < 0.002), other markers of inflammation and, notably, fetuin (r(s) = -0.442; p < 0.002). Regression analysis selected previous time on D in Tx patients (r(m) = 0.400; p < 0.004), and C-reactive protein and OPG in D patients (r(m) = 0.518; p < 0.004) as the most predictive parameters of AS. Discriminant analysis confirmed the major role of age and D duration in the appearance of AS and evidenced male gender as a distinct risk condition. At variance, Tx duration was never associated with AS. In conclusion, as compared to D, renal Tx patients show serum levels of calcification inhibition proteins and of divalent ions closer to normal. As this is associated with a lower prevalence and severity of AS, it is suggested that Tx antagonize the accelerating role of D in the progression of vascular calcification. Assessment of both coronary calcifications and serum levels of calcification inhibitory proteins may be of value to identify those subjects at higher risk of development and progression of vascular lesions, among whom males have the highest rate., (2007 S. Karger AG, Basel)

The purpose of this study was to evaluate the use of respiratory-related ventricular coupling to differentiate patients with constrictive pericarditis (CP) and restrictive cardiomyopathy (RCM). In 18 histologically proven cases of CP, 6 patients with inflammatory pericarditis (IP), 15 RCM patients and 17 normal subjects, real-time cine MRI was performed in the cardiac short-axis (basal half of the ventricles) during operator-guided deep respiration. The images were analyzed for ventricular septal position and shape during early ventricular filling. Early diastolic septal inversion (I) or flattening (F) was found in all CP (I:15,F:3), and in all IP (I:2,F:4), but seldom in normals (F:1) and not in RCM. The septal abnormalities occurred at the onset of inspiration and rapidly disappeared with the next heartbeats. The amount of ventricular coupling was evaluated by quantifying the difference in the maximal septal excursion between inspiration and expiration. This parameter, normalized to the biventricular diameter, was significantly larger in CP (20.0+/-4.5%, P<0.0001) and IP (14.8+/-3.2%, P<0.0001) patients than in normals (7.0+/-2.4%), whereas RCM patients had a trend toward decreased excursion (4.2+/-1.7%, P=0.11). A cut-off value of 11.8% (mean normals +2 SD) enabled to differentiate CP patients from normals and RCM patients completely. Real-time cine MRI can easily depict increased ventricular coupling, which may be helpful to better differentiate between CP and RCM patients, especially in patients with normal or minimally thickened pericardium. The increase in coupling in IP patients is likely caused by decreased compliance of the inflamed pericardial layers.

Our objective was to retrospectively evaluate the ability of multidetector-row computed tomography (MDCT) to detect previous myocardial infarctions (MIs) and to correlate necrosis with the status of coronary arteries supplying the infarcted territory. After having clinically evaluated 187 patients referred for ECG-gated MDCT of the coronary arteries, 30 previous MIs were identified in 29 patients (9 recent and 21 chronic). MDCT data were evaluated qualitatively and quantitatively by measuring attenuation values and wall thickness within the infarcted region and normal adjacent myocardium. Each MI was also assigned to the distribution territory of a coronary vessel, and morphological data were combined with MDCT angiographic findings. MDCT was able to detect 25/30 MIs showing an overall sensitivity and specificity of 83 and 91%, respectively. Quantitative analysis revealed a statistically significant difference in attenuation values between normal and infarcted regions (38.9+/-14 HU vs. 104.0+/-16 HU). Regional wall thinning was observed in chronic MIs (4.1+/-2 mm vs. 10.5+/-3.8 mm), and not in patients with recent event (7.9+/-1.6 mm vs 9.1+/-4 mm). In 22/25 cases, MDCT angiographic findings showed the presence of suspicious critical lumen narrowing (n=3), previous coronary stenting (n=14) and surgical revascularization (n=5) in the infarct-related coronary. During a single examination, MDCT might provide comprehensive imaging of MI offering a combined morphological and angiographic assessment.

To investigate the possibility of reducing X-ray exposure during multidetector-row spiral computed tomographic (MDCT) angiography and to compare the image quality and diagnostic accuracy of different dosages with digital subtraction angiography (DSA) in the evaluation of the infra-renal aorta and lower extremities vessels. Seventy-five patients, randomly divided into three groups of 25 patients each, were evaluated for atherosclerotic disease with four-row spiral CT angiography (4x2.5 mm) and DSA. MDCT scanning parameters were kept constant, except for milliamperage (mAs): group A: 50 mAs; group B: 100 mAs; group C: 130 mAs. Images were analysed by two vascular radiologists in consensus. DSA represented the standard of reference. The diagnostic value of MDCT and total radiation exposure were evaluated for each data set. The simulated effective dose was 3.7 mSv for 50 mAs, 8.2 mSv for 100 mAs and 13.7 mSv for 130 mAs for men, and 4 mSv for 50 mAs, 8.9 mSv for 100 mAs and 14.8 mSv for 130 mAs for women. The dose reduction was 74% for group A and 40% for group B. The evaluation of the presence and degree of stenoses revealed a sensitivity, specificity, accuracy, PPV and NPV of 96%, 94%, 95%, 83% and 99% for Group A (50 mAs), 96%, 96%, 96%, 89% and 99% for Group B (100 mAs) and 98%, 96%, 97%, 91% and 100% for the standard dose protocol, Group C (130 mAs). Low-dose scanning is thus a feasible and accurate option for four-row CT angiography of the peripheral vessels. This technique provides substantial reduction of the radiation dose delivered to the patient while maintaining optimal diagnostic accuracy.

The purpose of this study was to assess the feasibility of magnetic resonance imaging (MRI) to evaluate in real-time, the effects of respiration in ventricular septal motion and configuration in normal volunteers and cardiac patients. Real-time cine MRI studies, using the steady-state free precession (SSFP) technique, were performed in the cardiac short-axis during operator-guided deep inspiration and expiration in normal volunteers (N = 6), and in patients with constrictive pericarditis (CP; N = 6), restrictive cardiomyopathy (RCM; N = 4), chronic cor pulmonale (N = 5), and pericardial effusion. The respiratory effects on septal position and configuration during early ventricular filling were visually assessed. Results were compared with the short-axis breath-hold cine MRI studies, obtained at end-inspiration. In CP patients, onset of inspiration led to a leftward inversion in four of six patients and flattening of the septum in two of six patients during early ventricular filling. Septal abnormalities progressively disappeared during the following heartbeats. A similar pattern was found in one of six patients with pericardial effusion. The above pattern was absent in RCM patients. Although septal flattening during early inspiration was also found in two of six normal volunteers, flattening was minimal compared to that in CP patients. In all cor pulmonale patients, septal flattening or inversion was present, but this was not influenced by respiratory motion. Real-time cine MRI is a promising technique for determining the influence of respiration on septal motion and might be helpful in differentiating between different causes of impaired ventricular filling., ((c) 2005 Wiley-Liss, Inc.)

Magnetic resonance (MR) is an ideal technique for the evaluation of the pericardium since it enables the combination of high resolution anatomical images of the pericardial layers with functional information concerning the impact of pathology on diastolic heart function and cardiac filling in particular. In comparison with echocardiography, which remains the first choice technique for the study of the pericardium, MR provides larger fields of view allowing the visualisation of the entire chest, higher spatial and contrast resolution and greater reproducibility. The technique becomes particularly useful when ultrasound imaging does not provide adequate diagnostic information or requires further characterisation; ''non-echoic'' patients, loculated pericardial effusions, focal thickening of the layers and pericardial masses are usually better assessed with MR. The method also provides valuable diagnostic information for establishing the diagnosis of constrictive pericarditis and to differentiate this condition from restrictive cardiomyopathy. The aim of this paper is to present the role of MR imaging in the assessment of a patient with suspected pericardial disease, and discuss the MR technique, anatomy and the main pathological conditions.

Background: Coronary artery disease (CAD) is the most common cause of hospitalization and mortality in many industrialized countries. We analysed the diagnostic accuracy of multi-detector row spiral computed tomography (MDCT) in determining mid- to high-grade coronary artery stenoses (> 50%)., Methods: Sixty-nine patients with suspected CAD were referred to MDCT coronary angiography. Patients with a heart rate above 60 bpm received 20-40 mg propranol before the scan. The left main (LM), the left anterior descending artery (LAD), the first diagonal branch (D1), the right coronary artery (RCA) and the proximal tract of the circumflex artery (LCX) were independently evaluated by two blinded observers and screened for > 50% stenoses. The mean values of MDCT coronary narrowings assessed by two observers were compared to quantitative coronary angiography., Results: MDCT correctly detected 95 of 123 coronary lesions (sensitivity 77.2%) and absence of stenoses was correctly identified in 388 of 426 segments (specificity 91%). The sensitivity for the LM, LAD, RCA and the proximal tract of LCX was 100%, 86.5%, 69.8% and 80% respectively. Classification of patients as having 1-vessel, 2-vessels, 3-vessels or left main disease was accurate in 75.4% (46/61) of patients., Conclusions: MDCT technology, combined with heart rate control, allows reliable noninvasive detection of hemodynamically significant CAD.

Over the past decades, the feasibility of non-invasive coronary imaging has been explored using different modalities, such as magnetic resonance and electron beam computed tomography. Despite encouraging initial results, neither technique is yet considered suitable for routine clinical use. Recent developments in multidetector computed tomography have expanded the potential of contrast-enhanced spiral computed tomography coronary angiography. Promising results have been published with the use of 4-slice spiral computed tomography; however, cardiac motion and calcium deposits in the artery wall rendered a substantial number of scans inadequate for interpretation. Recently, a new generation of scanners, equipped with more and thinner detector rows (8 and 16 detectors) and an increased rotation speed, have been introduced. These technical advances will have a significant impact on cardiac imaging: at an increased gantry rotation rate, up to 32 slices can be acquired in 1 s. The improved spatial and temporal resolutions have led to the opportunity of acquiring high-quality images of the entire heart within a single breath-hold.

Purpose: The purpose of this study was to compare contrast enhanced MR angiography (MRA) with gadopentetate dimeglumine (Gd-DTPA) to MRA with gadobenate dimeglumine (Gd-BOPTA), a high relaxivity paramagnetic contrast agent., Materials and Methods: Twelve patients referred for carotid artery stenosis were examined with MR angiography using a fast spoiled gradient echo sequence. Gd-DTPA and Gd-BOPTA enhanced MR angiography were performed within 48-72 hours using a dose of 0.1 mmol/kg for Gd-BOPTA and 0.2 mmol/kg for Gd-DTPA, at a flow rate of 2 ml/s. Images were evaluated by two blinded radiologists. Qualitative and quantitative evaluations were performed comparing the sets of images from the two examinations., Results: Qualitative evaluation demonstrated superior arterial contrast enhancement and vessel conspicuity with Gd-BOPTA compared with Gd-DTPA. Quantita-tive evaluation showed an improvement in both signal intensity and contrast to noise ratio with Gd-BOPTA., Conclusion: The greater relaxivity of Gd-BOPTA, at lower doses, compared with Gd-DTPA, provides higher intravascular signal and signal to noise ratio. Gd-BOPTA appears to be an optimal contrast agent for contrast enhanced MRA.

Purpose: To evaluate the possible role of multislice spiral computed tomography (MSCT) as the sole imaging examination in the preoperative assessment of potential donors undergoing adult-to-adult living donor liver transplantation (LDLT)., Materials and Methods: Fifteen patients underwent MSCT with 0.5-second gantry rotation time. Pre- (4 X 2.5 mm collimation) and post-contrast (4 X 1 mm collimation) acquisitions during arterial and portal venous phases were performed after intravenous administration of 140 ml of non ionic contrast agent at 4-5 ml/s, with a delay time of 25 and 60 seconds, respectively. Pre-contrast scans with 80 and 140 kVp were acquired at the same level used to assess liver density. Real-time interaction with the post-contrast 3D data set was performed on a dedicated workstation to determine total and lobar liver volume, and to assess arterial and venous vascular anatomy., Results: Steatosis was found in three patients, who as a consequence were excluded as possible candidates. MSCT correctly identified five cases of arterial anatomical variations: two cases of the right hepatic artery arising from the superior mesenteric artery, two cases of the common hepatic artery arising from the superior mesenteric artery and one case of the left hepatic artery arising from left gastric artery. In two cases portal trifurcation was considered a criterion for exclusion. A 4% error in the liver volume calculation was found at surgery, in no case considered significant. Two patients underwent surgery and three have been short-listed., Conclusions: MSCT enables complete preoperative evaluation of potential donors undergoing LDLT. Total and lobar volume determination provided accurate and reproducible information. MSCT enabled correct surgical planning without intra-operative complications. One of the limits of the technique was the poor visualization of the biliary anatomy with the need to perform an intraoperative cholangiography in all the patients.

Sea urchin DNA (cytosine-5)-methyltransferase (Dnmt1) that is responsible for maintenance of DNA methylation patterns clearly shares similarity with various Dnmt1s identified in vertebrates. In this study, we determined the structure of the sea urchin Dnmt1 gene by screening a genomic library of the sea urchin Paracentrotus lividus with the complementary DNA (cDNA) as probe. Analysis of the positive clones demonstrated that the Dnmt1 gene consists of 34 exons and 33 introns spanning a distance of 35 kb. All exon-intron junction sequences agree with the GT/AG consensus with the exception of the 3' acceptor site of intron 8 where CT replaces AG consensus. The differences in the total number of exons between sea urchin and mouse genes reside mainly in the N-terminal region of the protein (exons 5-7 of the sea urchin, exons 5-12 of the mouse) where there is very low similarity in the amino acid sequence. By reverse transcription-polymerase chain reaction using oligonucleotides spanning different regions of the cDNA we carried out a comprehensive analysis of alternative splicing of the Dnmt1 messenger RNA (mRNA) in sea urchin embryos at different stages of development. We demonstrated the presence of at least five alternative spliced mRNAs that are regulated during development and are translated in truncated or deleted proteins.

The clinical and radiological features in three cases of cystic angiomatosis of bone are reported. Although these features are generally diagnostic except from histiocytosis X, the definitive diagnosis must be established by a pathological study, preferably of a segment of an involved rib or fibula. The prognosis varies according to the type of clinical presentation-in particular upon whether the lesions are solely skeletal or whether there is extraskeletal visceral involvement. Whereas these last cases may often prove fatal, those with only skeletal involvement have a favourable prognosis: indeed, the cystic bone lesions may regress without any treatment, as occurred in some cases reported in the literature and in two of our three cases.