Role of diffusion-weighted imaging in the discrimination of purulent intrasinusal content: A retrospective study.

OBJECTIVES: The objective of this study was to analyse MRI with morphological (T1, T2) and diffusion sequences (DWI, b1000) in patients presenting non-aggressive patterns of sinus opacity and operated on by functional endoscopic sinus surgery (FESS). DESIGN: A retrospective study. SETTING: Diffusion imaging in paranasal sinus pathology remains little known. To date, no imaging system is capable of determining the purulent content of a non-enhanced sinus filling. PARTICIPANTS: We included consecutive patients having undergone FESS in whom MRI of the paranasal sinuses was performed. Subjects were allocated to Case (pus) or Control (no pus) groups depending on sinus content found intraoperatively. FESS was performed for bacterial acute rhinosinusitis, acute exacerbations of chronic rhinosinusitis, non-purulent sinusitis, naso-sinusal polyposis, antrochoanal polyp, isolated polyp, angiomatous polyp and eosinophilic fungal sinusitis. Tumours, mucoceles and fungus balls were excluded. MAIN OUTCOME MEASURES: We analysed T1, T2, b1000 and MRI sequences and ADC map. RESULTS: On univariate analysis, intermediate signal in T2 and high signal in b1000 were associated with Cases (P < 0.001) as were low ADC values (P < 0.001). The difference in mean ADC values between Cases and Controls was statistically significant (respectively, 0.518 vs 2.041 × 10-3  mm2 /sec, P < 0.01). On multivariate analysis, MRI with ADC < 0.725 × 10-3  mm2 /sec and b1000_SI > brain was significantly associated with the case group. MRI with b1000_SI < brain and ADC > 1.450 × 10-3  mm2 /sec was significantly associated with the control group. CONCLUSIONS: Diffusion MRI offers extremely promising results regarding content characterisation of infectious sinus diseases.

The value of a rapid contrast-enhanced angio-MRI protocol in the detection of head and neck paragangliomas in SDHx mutations carriers: a retrospective study on behalf of the PGL.EVA investigators.

OBJECTIVES: To assess the performance of a simplified MRI protocol consisting of a contrast-enhanced three-dimensional MR angiography (CE-MRA) in association with a post-contrast T1-weighted sequence (T1WIV) for the detection of HNPGLs in SDHx mutation carriers. METHODS: This retrospective sub-study is based on the multicenter PGL.EVA cohort, which prospectively enrolled SDHx mutation carriers from 2005 to 2009; 157 index cases or relatives were included. CE-MRA and the T1WIV images were read solely with knowledge of the clinical data but blind to the diagnosis. Sensitivity, specificity and likelihood ratios for the simplified MRI protocol were compared to the full MRI protocol reading results and to the gold standard status obtained through the consensus of an expert committee. RESULTS: The sensitivity and specificity of the readings of the simplified MRI protocol were, respectively, 88.7 % (95 % CI = 78.1-95.3) and 93.7 % (95 % CI = 86.8-97.7) versus 80.7 % (95 % CI = 68.6-89.6) and 94.7 % (95 % CI = 88.1-98.3) for the readings of the full MRI protocol. CONCLUSIONS: The simplified post-contrast MRI with shorter duration (5 to 10 minutes) showed no performance difference compared to the lengthy standard full MRI and can be proposed for the detection of head and neck paragangliomas (HNPGLs) in SDHx mutation carriers. KEY POINTS: • Rapid angio-MRI protocol and the usual lengthy protocol show equal diagnostic performance. • The CE-MRA is the key sequence for the detection of HNPGLs. • The T1WIV sequence assists in localizing HNPGLs.

Assessment of myocardial partition coefficient of gadolinium (λ) in dilated cardiomyopathy and its impact on segmental and global systolic function.

PURPOSE: 1) To assess the myocardial partition coefficient (λ) of gadolinium quantified using T1 mapping in dilated cardiomyopathy (DCM); and 2) to assess the impact of increased λ on left ventricular (LV) circumferential strain and ejection fraction in DCM. MATERIALS AND METHODS: Seventeen patients with DCM and 11 controls were prospectively included. All patients and controls underwent a 1.5 T MRI using: 1) cine to quantify LV volumes and function; 2) tagging to quantify circumferential strain in mid-LV; 3) T1 mapping before and 9 minutes after contrast injection to quantify R1, ΔR1, and λ; and 4) inversion recovery 3D Flash was used to assess late gadolinium enhancement (LGE) 10 minutes after Gd DOTA injection (0.2 mmol/kg). We used Student's t-test to compare means, Pearson's test for correlation assessment, and a mixed linear model to integrate the dependency between myocardial segments. RESULTS: No difference in median λ was measured between patients with (0.52 [interquartile range = 0.48-0.56]) and without enhancement on LGE (0.51 [0.47-0.54]; P = 0.07). Circumferential strain value measured in each segment was correlated with the λ measured in the corresponding segment (r = 0.55; P < 0.0001). Multivariate analysis revealed a significant link between the λ in each segment and circumferential strain (0.002 ± 0.001; P = 0.009) and also with ejection fraction (-0.001 ± 0.0008; P = 0.04). CONCLUSION: In DCM, λ correlates independently with circumferential strain and ejection fraction, suggesting that there is a link between λ and systolic function.

Incidence, predictors, and prognostic value of intramyocardial hemorrhage lesions in ST elevation myocardial infarction.

BACKGROUND: Intra myocardial hemorrhage lesions (IMH) are underdiagnosed complication of ST elevation myocardial infarction (STEMI). We sought to determine the incidence, predictors and the prognostic value of IMH in STEMI using cardiac MR imaging (CMR) techniques. METHODS: We screened for inclusion consecutive patients with STEMI treated by percutaneous coronary intervention (PCI) within the first 12 hr of evolution. IMH lesions were identified on T2-weighted sequences on CMR between days 4 and 8 after PCI. Adverse cardiac events were defined as a composite of death + severe ventricular arrhythmias + acute coronary syndrome + acute heart failure. RESULTS: N = 114 patients were included and n = 11 patients (10%) presented IMH lesions. Patients with IMH lesions had a larger myocardial infarction extent (25.6 ± 1.8 vs. 13.5 ± 1.0 % LV mass, P < 0.01), microvascular obstructive lesions extent (4.6 ± 1.0 vs. 1.3 ± 0.3% LV mass, P < 0.01) and lower LV ejection fraction (40.7 ± 2.3% vs. 50.7 ± 1.3%, P < 0.01). The value of glycemia at admission was an independent predictor of IMH development (Odd ratio 1.8 [1.1-2.8] per mmol l(-1), P = 0.01). The incidence of adverse cardiac events was higher in the IMH group than in the non-IMH group during the first year following STEMI (P = 0.01, log-rank analysis). Cox regression analysis identified the presence of IMH lesions as an independent predictor of adverse clinical outcome (Hazard Ratio = 2.8 [1.2-6.8], P = 0.02). CONCLUSION: Our study indicates that IMH is a rare but severe finding in STEMI, associated with a larger myocardial infarction and a worse clinical outcome. Per-PCI glycemia might influence IMH development.

Gender differences in response to cold pressor test assessed with velocity-encoded cardiovascular magnetic resonance of the coronary sinus.

BACKGROUND: Gender-specific differences in cardiovascular risk are well known, and current evidence supports an existing role of endothelium in these differences. The purpose of this study was to assess non invasively coronary endothelial function in male and female young volunteers by myocardial blood flow (MBF) measurement using coronary sinus (CS) flow quantification by velocity encoded cine cardiovascular magnetic resonance (CMR) at rest and during cold pressor test (CPT). METHODS: Twenty-four healthy volunteers (12 men, 12 women) underwent CMR in a 3 Tesla MR imager. Coronary sinus flow was measured at rest and during CPT using non breath-hold velocity encoded phase contrast cine-CMR. Myocardial function and morphology were acquired using a cine steady-state free precession sequence. RESULTS: At baseline, mean MBF was 0.63 ± 0.23 mL·g⁻¹·min⁻¹ in men and 0.79 ± 0.21 mL·g⁻¹·min⁻¹ in women. During CPT, the rate pressure product in men significantly increased by 49 ± 36% (p < 0.0001) and in women by 52 ± 22% (p < 0.0001). MBF increased significantly in both men and women by 0.22 ± 0.19 mL·g⁻¹·min⁻¹ (p = 0.0022) and by 0.73 ± 0.43 mL·g⁻¹·min⁻¹ (p = 0.0001), respectively. The increase in MBF was significantly higher in women than in men (p = 0.0012). CONCLUSION: CMR coronary sinus flow quantification for measuring myocardial blood flow revealed a higher response of MBF to CPT in women than in men. This finding may reflect gender differences in endothelial-dependent vasodilatation in these young subjects. This non invasive rest/stress protocol may become helpful to study endothelial function in normal physiology and in physiopathology.

Measurement of trabeculated left ventricular mass using cardiac magnetic resonance imaging in the diagnosis of left ventricular non-compaction.

AIMS: To describe a method for measuring trabeculated left ventricular (LV) mass using cardiac magnetic resonance imaging and to assess its value in the diagnosis of left ventricular non-compaction (LVNC). METHODS AND RESULTS: Between January 2003 and 2008, we prospectively included 16 patients with LVNC. During the mean period, we included 16 patients with dilated cardiomyopathy (DCM), 16 patients with hypertrophic cardiomyopathy (HCM), and 16 control subjects. Left ventricular volumes, LV ejection fraction, and trabeculated LV mass were measured in the four different populations. The percentage of trabeculated LV mass was almost three times higher in the patients with LVNC (32 +/- 10%), compared with those with DCM (11 +/- 4%, P < 0.0001), HCM (12 +/- 4%, P < 0.0001), and controls (12 +/- 5%, P < 0.0001). A value of trabeculated LV mass above 20% of the global mass of the LV predicted the diagnosis of LVNC with a sensitivity of 93.7% [95% confidence interval (CI), 71.6-98.8%] and a specificity of 93.7% (95% CI, 83.1-97.8%; kappa = 0.84). CONCLUSION: The method described is reproducible and provides an assessment of the global amount of LV trabeculation. A trabeculated LV mass above 20% of the global LV mass is highly sensitive and specific for the diagnosis of LVNC.

Effectiveness of endovascular embolization with a collagen-based embolic agent (Marsembol) in an animal model.

PURPOSE: To investigate in a porcine experimental model the effectiveness, tissue penetration, and histologic impact of renal artery embolization with a collagen-based nonadhesive embolic agent, marsembol. MATERIALS AND METHODS: Fifteen pigs underwent embolization of one interlobular artery of the renal artery with collagen-resorcinol gel emulsified with Lipiodol and further polymerized with glutaraldehyde-formaldehyde mixture. Angiograms were obtained before, during, and after the procedure. Animals were euthanized at day 0 (n = 3), 1 week (n = 3), or 3 months (n = 7), and flat-panel three-dimensional rotational radiologic images of the kidneys were obtained. Arterial, medullary, and cortical samples were taken for histologic and scanning electron microscopic investigations. RESULTS: Fifteen interlobular renal arteries were successfully embolized by delivering 1.7 mL + or - 0.2 of the embolic agent. All the embolized arteries remained occluded at 3 months, leading to a major atrophy of the embolized portions of the kidneys. Imaging and histologic findings show that the embolic agent provided a distal vessel occlusion and entirely filled the lumen of the arteries up to the glomerular tufts. The homogeneous plug formed by the embolic agent induces very few inflammatory responses. The regenerative tubular processes were arrested at 3 months. CONCLUSIONS: The collagen-based embolic agent described here has the properties required to perform embolization. These specific properties lead to very distal vessel embolization. The embolic agent is effective at 3 months in renal embolization.

Sonographic diagnosis of a cervical vagal schwannoma.

This case report illustrates the role of high-resolution sonography in the preoperative assessment of a schwannoma of the vagus nerve in the neck. Sonography identified the tumor in the right carotid space and determined its origin from the right vagus nerve, facilitating the surgeon's approach to preserve nerve function.

Clusterin increases post-ischemic damages in organotypic hippocampal slice cultures.

Clusterin or apolipoprotein J is a heterodimeric glycoprotein which is known to be increased during tissue involution in response to hormonal changes or injury and under circumstances leading to apoptosis. Previous studies in wild-type (WT) and clusterin-null (Clu-/-) mice indicated a protective role of clusterin over-expression in astrocytes lasting up to 90 days post-ischemia. However, in in vitro and in vivo models of neonatal hypoxia-ischemia, clusterin exacerbates necrotic cell death. We developed recombinant forms of clusterin and examined their effect on propidium iodide uptake, neuronal and synaptic markers as well as electrophysiological recordings in hippocampal slice cultures from Clu-/- and WT mice subjected to oxygen-glucose deprivation (OGD). WT mice displayed a marked up-regulation of clusterin associated with electrophysiological deficits and dramatic increase of propidium iodide uptake 5 days post-OGD. Immunocytochemical and western blot analyses revealed a substantial decrease of neuronal nuclei and synaptophysin immunoreactivity that predominated in WT mice. These findings contrasted with the relative post-OGD resistance of Clu-/- mice. The addition of biologically active recombinant forms of human clusterin for 24 h post-OGD led to the abolishment of the ischemic tolerance in Clu-/- slices. This deleterious effect of clusterin was reverted by the concomitant administration of the NMDA receptor antagonist, d-2-amino-5-phosphonopentanoate. The present data indicate that in an in vitro model of ischemia characterized by the predominance of NMDA-mediated cell death, clusterin exerts a negative effect on the structural integrity and functionality of hippocampal neurons.

Molecular gene cloning and overexpression of the phytase from Debaryomyces castellii CBS 2923.

The ORF encoding the Debaryomyces castellii CBS 2923 phytase was isolated. The deduced 461-amino-acid sequence corresponded to a 51.2 kDa protein and contained the consensus motif (RHGXRXP) which is conserved among phytases. No signal sequence cleavage site was detected. Nine potential N-glycosylation sites have been predicted. The protein shared 21-69% sequence identities with various phytases of yeast or fungal origin. Heterologous expression of the D. castellii CBS 2923 phytase in the methylotrophic yeast Pichia pastoris was tested under both the P. pastoris inducible alcohol oxidase (AOX1) promoter and the constitutive glyceraldehyde-3-phosphate dehydrogenase (GAP) promoter. Maximum production levels obtained were 476 U ml(-1), with the AOX1 expression system and 16.5 U ml(-1) with the GAP one. These productions corresponded to a 320-fold and a 10-fold overexpression of the protein, respectively as compared to the homologous production. The biochemical characteristics of the recombinant phytase were identical to those of the native enzyme.

Shear Wave Elastography in Head and Neck Lymph Node Assessment: Image Quality and Diagnostic Impact Compared with B-Mode and Doppler Ultrasonography.

The aim of this study was to assess the diagnostic performance of shear wave elastography (SWE) in comparison to B-mode and Doppler ultrasonography in differentiating benign from malignant head and neck lymph nodes (HNLNs). Sixty-two HNLNs from 56 patients were prospectively examined using B-mode, Doppler and SWE. The standard of reference was histopathology or cytology and follow-up. Qualitative malignant criteria (hilum infiltration, cortical hypo-echogenicity, irregular margins, abnormal vessels) were assessed on a five-point scale. Four quantitative parameters were obtained: long axis length, short axis length, short axis/long axis ratio, resistive index and maximum shear elasticity modulus (µmax). Diagnostic performance was analyzed with special emphasis on the sub-centimeter HNLN subgroup. Thirty HNLNs were malignant (48%). µmax intra-observer reproducibility was 0.899 (0.728 in sub-centimeter subgroup). Malignant HNLNs were stiffer (µmax = 72.4 ± 59.0 kPa) compared with benign nodes (µmax = 23.3 ± 25.3 kPa) (p < 0.001). Among the quantitative criteria, µmax had the highest diagnostic accuracy (area under the curve = 0.903 ± 0.042), especially in the sub-centimeter subgroup (area under the curve = 0.929 ± 0.045; p < 0.001) in which the area under the curve was significantly higher compared with the other quantitative criteria (p < 0.05). The additional use of SWE combined with B-mode tended to improve diagnostic accuracy (p > 0.05). SWE is a promising reproducible quantitative tool with which to predict malignant HNLNs, especially sub-centimeter nodes.

Recombinant expression and anti-microbial activity of anti-lipopolysaccharide factor (ALF) from the black tiger shrimp Penaeus monodon.

Anti-lipopolysaccharide factors (ALFs), originally characterized from horseshoe crabs, have been recently identified from hemocytes of the black tiger shrimp, Penaeus monodon, by a genomic approach. In order to characterize the properties and biological activities of this immune effector in shrimp, ALFPm3, the most abundant isoform found in P. monodon, was expressed in the yeast Pichia pastoris. Large-scale production in fermentor provided 262 mg/l of recombinant ALFPm3 which was purified to homogeneity by single chromatography step on expanded-bed Streamline SP6XL. The rALFPm3 was further characterized in terms of N-terminal sequencing and mass spectrometry. Anti-microbial assays demonstrated that rALFPm3 has a broad spectrum of anti-fungal properties against filamentous fungi, and anti-bacterial activities against both Gram-positive and Gram-negative bacteria, associated with a bactericidal effect. Interestingly, rALFPm3 is highly efficient against various Vibrio species including strains pathogenic for shrimp. Finally, a synthetic peptide corresponding to a part of the putative LPS-binding site of ALFPm3 was shown to display activities mainly directed against Gram-positive bacteria indicating the involvement of the full molecule to the anti-microbial activity for Gram-negative bacteria.

Magnetic resonance spectroscopy of paragangliomas: new insights into in vivo metabolomics.

Paragangliomas (PGLs) can be associated with mutations in genes of the tricarboxylic acid (TCA) cycle. Succinate dehydrogenase (SDHx) mutations are the prime examples of genetically determined TCA cycle defects with accumulation of succinate. Succinate, which acts as an oncometabolite, can be detected by ex vivo metabolomics approaches. The aim of this study was to evaluate the potential role of proton magnetic resonance (MR) spectroscopy ((1)H-MRS) for identifying SDHx-related PGLs in vivo and noninvasively. Eight patients were prospectively evaluated with single voxel (1)H-MRS. MR spectra from eight tumors (four SDHx-related PGLs, two sporadic PGLs, one cervical schwannoma, and one cervical neurofibroma) were acquired and interpreted qualitatively. Compared to other tumors, a succinate resonance peak was detected only in SDHx-related tumor patients. Spectra quality was considered good in three cases, medium in two cases, poor in two cases, and uninterpretable in the latter case. Smaller lesions had lower spectra quality compared to larger lesions. Jugular PGLs also exhibited a poorer spectra quality compared to other locations. (1)H-MRS has always been challenging in terms of its technical requisites. This is even more true for the evaluation of head and neck tumors. However, (1)H-MRS might be added to the classical MR sequences for metabolomic characterization of PGLs. In vivo detection of succinate might guide genetic testing, characterize SDHx variants of unknown significance (in the absence of available tumor sample), and even optimize a selection of appropriate therapies.

Transjugular intrahepatic porto-systemic shunt is a risk factor for liver dysplasia but not hepatocellular carcinoma: a retrospective study of explanted livers.

BACKGROUND: Conflicting data exist regarding the risk for hepatocellular carcinoma after transjugular intrahepatic porto-systemic shunt (TIPS) insertion in cirrhotic patients. METHODS: We retrospectively analysed histopathological data from 214 patients who were transplanted in our Institution including 68 patients who underwent TIPS placement before transplantation. Pathological lesions from explanted livers, including incidental hepatocellular carcinoma, small cell dysplasia and large cell dysplasia were recorded. RESULTS: Pathological lesions were found in 36.4% of explanted livers. TIPS insertion was an independent risk factor for pathological lesion (HR = 2.11, p < 0.05), concurrently with age (HR = 1.10 per year, p < 0.001) and viral aetiology of cirrhosis (HR = 3.05, p < 0.001). When considering the different type of lesions, TIPS insertion was not associated with an increased risk for hepatocellular carcinoma but was an independent risk factor for liver dysplasia (HR = 2.15, p = 0.042). CONCLUSION: Although a direct relationship between TIPS insertion and hepatocellular carcinoma risk was not demonstrated in this study, the increased frequency of liver dysplasia observed in TIPS-bearing explanted livers deserves further prospective investigations with adequate follow-up.

High-level expression of Candida parapsilosis lipase/acyltransferase in Pichia pastoris.

Candida parapsilosis has been previously shown to produce a lipase/acyltransferase (EC 3.1.1.3) that preferentially catalyses transfer reactions such as alcoholysis over hydrolysis in the presence of suitable nucleophiles other than water, even in aqueous media (aw > 0.9 ). This enzyme has been shown to belong to a new family of lipases. The present work describes the cloning of the gene coding for this lipase/acyltransferase in the yeast Pichia pastoris and the heterologous high-level expression of the recombinant enzyme. The lipase/acyltransferase gene, in which the sequence encoding the signal peptide was replaced by that of the alpha-factor of Saccharomyces cerevisiae, was placed under the control of the methanol inducible promoter of the alcohol oxidase 1 gene (AOX1). A transformed P. pastoris clone, containing five copies of the lipase/acyltransferase gene, was selected for the production of recombinant enzyme. The fed-batch culture supernatant contained 5.8 gl(-1) (weighted) of almost pure recombinant lipase/acyltransferase displaying the same catalytic behavior as the original enzyme.

Virtual laryngotracheal endoscopy based on geometric surface modeling using spiral computed tomography data.

This prospective study describes the clinical utility of virtual endoscopy based on geometric surface modeling of the laryngotracheal lumen. Eighteen children with dyspnea related to either subglottic angioma (n = 5) or laryngotracheal stenosis (n = 13) were included. All patients underwent video-recorded operative endoscopy, spiral computed tomography, and 3-dimensional reconstruction of the laryngotracheal lumen. Modeling was achieved by contour detection on spiral computed tomographic images and reconstruction using a geometric shape-recognition algorithm. The generated surface was used for diagnosis and measurement using interactive and automatic tools. Findings of virtual endoscopy and operative endoscopy were compared. Virtual endoscopy confirmed narrowing of the airway in all cases. In 9 cases, high-grade stenosis prevented complete operative endoscopy, but virtual endoscopy allowed accurate assessment and measurement of the stenosis. The findings of operative and virtual endoscopy were concordant in 9 cases. We conclude that surface modeling provides valuable information for preoperative evaluation of laryngotracheal narrowing. The ability to assess extraluminal anatomy provides a clearer picture of overall disease involvement. In the future, virtual endoscopy will probably be used in conjunction with operative endoscopy for therapeutic decision-making. Noninvasive virtual endoscopy could become an alternative to traditional endoscopy under general anesthesia for therapeutic follow-up.

Cardiac multidetector computed tomography in infective endocarditis: a pictorial essay.

OBJECTIVES: The goals of this pictorial essay are: (1) to set out a multislice computed tomography (MSCT) imaging protocol to assess infective endocarditis (IE); (2) to give an MSCT overview of valvular and peri-valvular involvement during IE; (3) to give a CT overview of septic embolism and infectious pseudoaneurysms during IE. METHODS: MSCT acquisition protocols to assess IE are performed in two different phases: the first acquisition, under electrocardiography (ECG) gating, covers the cardiac structures during first-pass iodine injection; the second acquisition covers the thorax, abdomen, pelvic and cerebral regions. RESULTS: Valvular and peri-valvular lesions during IE are: vegetation-a hypodense, homogeneous, irregular mass on a valve or endocardial structure; perforation-a defect in the leaflet; valvular aneurysm-loss of the homogenous curvature of the leaflet; valvular thickening; peri-valvular abscess; pseudoaneurysm; fistula and disinsertion of a prosthetic valve. Extra-cardiac location could involve all organs. CONCLUSIONS: MSCT can be considered as a useful complement in visualising the cardiac lesions of IE if echocardiography is inconclusive. MSCT is the only imaging modality that provides assessment of valvular and peri-valvular involvement, extra-cardiac lesions, and non-invasive evaluation of the coronary artery anatomy, simultaneously. MAIN MESSAGES: • MSCT provides assessment of coronary anatomy, cardiac and extra-cardiac lesions. • MSCT represents an alternative to echocardiography during IE. • Surgical valve replacement is usually required if vegetation is >10 mm. • Peri-valvular extension (abscesses, pseudoaneurysm and fistulae) required surgical treatment.

Prognostic value of preoperative coronary computed tomography angiography in patients treated by orthotopic liver transplantation.

OBJECTIVES: The aim of this study was to assess the feasibility of 64-slice coronary computed tomography (CT) angiography in patients treated by orthotopic liver transplantation, and to compare prognostic values of CT angiography and dobutamine stress echocardiography in the same population. METHODS: Eighty-two consecutive patients, without known coronary artery disease, who underwent orthotopic liver transplantation, were included in this study. A CT angiography was performed along with usual explorations including dobutamine stress echography. A one-year minimal follow-up was performed to seek cardiac events. RESULTS: Fifty-two (65.8%) patients underwent a CT angiography. Thirty-seven (71%) were totally normal or showed nonobstructive coronary plaque, six (12%) showed at least one obstructive coronary plaque greater than 50%. Nine (17%) of the examined patients had at least one nonassessable segment. A total of six (7.6%) major cardiac events occurred in a mean-time follow-up of 17.8 ± 12.7 months. CONCLUSION: CT angiography that is normal or with a nonobstructive coronary plaque has a negative predicting value of 95% [0.82-0.99] for major cardiac adverse events, and of 100% [0.91-1] for clinical coronary events in patients undergoing orthotopic liver transplantation. The prognostic value of CT angiography was comparable with that of dobutamine stress echography.

Gadolinium chelate kinetics in cardiac MR imaging of myocarditis: comparison to acute myocardial infarction and impact on late gadolinium enhancement.

OBJECTIVES: To compare the kinetics of gadolinium in myocarditis and myocardial infarction and to establish the best interval between contrast injection and late gadolinium-enhanced (LGE) image acquisition for the diagnosis of acute myocarditis. METHODS: Seventeen patients with acute myocarditis and 12 with acute myocardial infarction underwent Look-Locker sequences before and after administration of 0.2 mmol/kg gadolinium chelate for a period of 14 minutes. The apparent longitudinal relaxation rates (R'1) were calculated from left ventricular blood, enhanced and normal myocardium. LGE cardiac magnetic resonance images were acquired at 5, 10, and 15 minutes after contrast injection. The contrast between enhanced and normal myocardium (Contrastenhaced-normal) was measured, and the quality of the images was analyzed. RESULTS: A faster decline in the R'1 values measured in the areas of myocardial enhancement was recorded in myocarditis than that in myocardial infarction. In myocarditis, the Contrastenhaced-normal values decreased over time (from 60.7 ± 35.1 at 5 minutes vs. 42.1 ± 26.7 at 15 minutes; P = 0.001). However, in myocardial infarction, the Contrastenhaced-normal value remained stable in time (60.7 ± 22.9 at 5 minutes vs. 68.8 ± 16.6 at 15 minutes; P = ns). CONCLUSION: The gadolinium kinetics of acute myocarditis are different from those of acute myocardial infarction. In myocarditis, LGE images acquired 5 minutes after contrast injection provide higher Contrastenhaced-normal and better image quality compared with images taken at later points.