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61.
We aimed to evaluate the role of two-dimensional speckle tracking imaging (2DSTI) in detecting early changes of myocardial deformation in patients affected by thalassemia major (TM) and its relation with myocardial iron overload (MIO) detected by T2* cardiovascular magnetic resonance (CMR). We studied 28 TM patients (15 males, 37.4?±?10 years). All patients underwent CMR and echocardiography in the same day. Segmental and global T2* values were measured. Values of global longitudinal strain (GLS) were derived from the three apical views, while radial and circumferential strain were obtained as average strain from the short axis views at basal, mid and apical level. Six patients (21.4%) showed significant MIO (global heart T2*?<?20 ms). GLS showed a significant correlation with T2* values (R?=??0.49; P?=?0.001) and it was significantly lower in patients with a significant MIO than in those with no significant MIO (?18.3?±?2 vs. ?21.3?±?2.7, P?=?0.02). No significant difference was found for radial and circumferential strain in relation to the severity of MIO. Patients with impaired GLS (<?19.5%) had a significant higher risk of showing significant MIO (Odds-ratio-OR?=?17; 95%). GLS is related with global T2* in TM patients. Moreover, GLS can identify TM patients with severe MIO detected by CMR.  相似文献   
62.

Purpose

Diffuse remodeling of myocardial extra-cellular matrix is largely responsible for left ventricle (LV) dysfunction and arrhythmias. Our hypothesis is that the texture analysis of late iodine enhancement (LIE) cardiac computed tomography (cCT) images may improve characterization of the diffuse extra-cellular matrix changes. Our aim was to extract volumetric extracellular volume (ECV) and LIE texture features of non-scarred (remote) myocardium from cCT of patients with recurrent ventricular tachycardia (rVT), and to compare these radiomic features with LV-function, LV-remodeling, and underlying cardiac disease.

Procedures

Forty-eight patients suffering from rVT were prospectively enrolled: 5/48 with idiopathic VT (IVT), 23/48 with post-ischemic dilated cardiomyopathy (ICM), 9/48 with idiopathic dilated cardiomyopathy (IDCM), and 11/48 with scars from a previous healed myocarditis (MYO). All patients underwent echocardiography to assess LV systolic and diastolic function and cCT with pre-contrast, angiographic, and LIE scan to obtain end-diastolic volume (EDV), ECV, and first-order texture parameters of Hounsfield Unit (HU) of remote myocardium in LIE [energy, entropy, HU-mean, HU-median, standard deviation (SD), and mean absolute deviation (MAD)].

Results

Energy, HU mean, and HU median by cCT texture analysis correlated with ECV (rho?=?0.5650, rho?=?0.5741, rho?=?0.5068; p?<?0.0005). cCT-derived ECV, HU-mean, HU-median, SD, and MAD correlated directly to EDV by cCT and inversely to ejection fraction by echocardiography (p?<?0.05). SD and MAD correlated with diastolic function by echocardiography (rho?=?0.3837, p?=?0.0071; rho?=?0.3330, p?=?0.0208). MYO and IVT patients were characterized by significantly lower values of SD and MAD when compared with ICM and IDCM patients, independently of LV-volume systolic and diastolic function.

Conclusions

Texture analysis of LIE may expand cCT capability of myocardial characterization. Myocardial heterogeneity (SD and MAD) was associated with LV dilatation, systolic and diastolic function, and is able to potentially identify the different patterns of structural remodeling characterizing patients with rVT of different etiology.
  相似文献   
63.
Amitai  Marianne M.  Klang  Eyal  Levartovsky  Asaf  Rozendorn  Noa  Soffer  Shelly  Taha  Gadeer Ali  Ungar  Bella  Greener  Tomer  Ben-Horin  Shomron  Eliakim  Rami  Kopylov  Uri 《Abdominal imaging》2018,43(12):3207-3212
Background and aims

Distinguishing between fibrotic and inflammatory strictures in Crohn’s disease (CD) is still challenging. The capacity of diffusion-weighted (DWI) magnetic resonance (MRE) to identify intestinal fibrosis was recently demonstrated; however, the therapeutic implications of this association have never been evaluated. The aim of the current study was to identify imaging features, including DWI, which can predict response to anti-inflammatory treatment in patients with stricturing CD.

Methods

Consecutive CD patients with intestinal strictures that initiated treatment with anti-tumor necrosis alpha (anti-TNF) between June 2012 and April 2017 with MRE adjacent to treatment onset were retrospectively collected. The primary outcome was treatment failure, defined as drug discontinuation, CD-related surgery, or endoscopic dilatation of the stricture. Clinical, demographic, and imaging data were compared between patients who did and did not develop treatment failure within 12 months of anti-TNF treatment initiation.

Results

A total of 21 patients were included in the study; 9/21 (42.8%) developed treatment failure. None of the clinical/demographic parameters were associated with the risk of treatment failure. Among imaging parameters, only ADC value (< 1 × 10−3 mm2/s) was significantly associated with the risk of treatment failure (AUC = 0.81, 66% vs. 0%, p = 0.015).

Conclusions

Our results suggest that ADC value on DWI MRE may predict the risk of treatment failure in stricturing CD. If replicated in larger studies, these results may guide therapeutic decisions and suggest avoiding anti-TNF treatment.

  相似文献   
64.
BACKGROUNDOne third of coronavirus disease 2019 (COVID-19) patients have gastrointestinal symptoms. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA has been detected in stool samples of approximately 50% of COVID-19 individuals. Fecal calprotectin is a marker of gastrointestinal inflammation in the general population.AIMTo investigate if fecal calprotectin correlates with SARS-CoV-2 intestinal shedding in COVID-19 patients with pneumonia.METHODSPatients with SARS-CoV-2 pneumonia admitted to the Infectious Disease Unit (University Hospital of Trieste, Italy) from September to November 2020 were consecutively enrolled in the study. Fecal samples were collected and analyzed for quantification of fecal calprotectin (normal value < 50 mg/kg) and SARS-CoV-2 RNA presence by polymerase chain reaction (PCR). Inter-group differences were determined between patients with and without diarrhea and patients with and without detection of fecal SARS-CoV-2.RESULTSWe enrolled 51 adults (40 males) with SARS-CoV-2 pneumonia. Ten patients (20%) presented with diarrhea. Real-time-PCR of SARS-CoV-2 in stools was positive in 39 patients (76%), in all patients with diarrhea (100%) and in more than two thirds (29/41, 71%) of patients without diarrhea. Obesity was one of the most common comorbidities (13 patients, 25%); all obese patients (100%) (P = 0.021) tested positive for fecal SARS-CoV-2. Median fecal calprotectin levels were 60 mg/kg [interquartile range (IQR) 21; 108]; higher fecal calprotectin levels were found in the group with SARS-CoV-2 in stools (74 mg/kg, IQR 29; 132.5) compared to the group without SARS-CoV-2 (39 mg/kg, IQR 14; 71) (P < 0.001).CONCLUSIONHigh fecal calprotectin levels among COVID-19 patients correlate with SARS-CoV-2 detection in stools supporting the hypothesis that this virus can lead to bowel inflammation and potentially to the ‘leaky gut’ syndrome.  相似文献   
65.
66.
AIMS: Radiofrequency catheter ablation is effective at terminating ventricular tachycardia, but the overall clinical role of the technique in patients with a prior myocardial infarction is still debated, due to the uncertainties of the long-term reliability of the procedure. The purpose of this study was to prospectively investigate the relationship between acute results obtained by catheter ablation and long-term outcome in a homogeneous population of patients with post-myocardial infarction ventricular tachycardia. METHODS AND RESULTS: One hundred and twenty-four consecutive patients with recurrent, drug-refractory, haemodynamically tolerated ventricular tachycardia were included in the study. This population accounted for 30% of the patients with post-myocardial infarction ventricular tachycardia admitted between April 1992 and September 1997 to the investigating centres. The ablation was successful in eliminating sustained ventricular tachycardia in 91 of them (73%); a partial result was obtained in 21 (17%) and failure in 12 (10%). Low dose amiodarone and/or beta-blockers were maintained in 86% of the patients. Over a median follow-up of 41.5 months (interquartile range 30.5-59.5 months), there were 15 deaths (12%), three of which were sudden (2.4%); the 12 remaining patients died of heart failure. Event-free survival analysis showed a significantly lower ventricular tachycardia recurrence rate in patients with a successful procedure as compared to those with failure or a partial result (19% vs 53% at one year and 27% vs 60% at 3 years, P=0.003). A repeat procedure was performed in 15 patients with early recurrences and was followed in all by long-term success. Of those who submitted to a second procedure, 93/124 patients (75%) are free of ventricular tachycardia recurrences. An implantable cardioverter-defibrillator (ICD), following procedure failure, was implanted in 13 patients (11%) of the study population. CONCLUSIONS: Radiofrequency catheter ablation is effective in a wide population of patients with recurrent tolerated ventricular tachycardia, with very low sudden death and cardiac mortality rates over the long-term. Persistent ventricular tachycardia inducibility after catheter ablation requires an ICD implant and/or repeat ablation.  相似文献   
67.
Clinical and experimental data show that type I atrial flutter is due to a reentry mechanism with an excitable gap. To define the location of the reentry circuit of atrial flutter, width of excitable gap, poststimulation cycle and pattern of reset after premature stimulus were analyzed in 18 patients during atrial flutter at multiple atrial sites (high, lateral, posterior and septal right atrium, and coronary sinus). The pattern of reset was defined as flat or increasing whether the return cycle remained unchanged or prolonged with increasing prematurity. Shorter values of the excitable gap were found at the coronary sinus (33 +/- 8 ms) and high right atrium (30 +/- 10 ms) than at the posterior (43 +/- 9 ms) or septal right atrium (45 +/- 11 ms). Intermediate values (36 +/- 8 ms) were measured at the lateral right atrium. Poststimulation cycle, corrected for atrial flutter cycle length, was shorter in the posterior (6 +/- 7 ms) and septal right atrium (5 +/- 7 ms) than in the coronary sinus (35 +/- 9 ms), and the high (23 +/- 10 ms) and lateral right atrium (15 +/- 9 ms). A flat pattern of resetting occurred more frequently at the septal (18 of 18 patients) and posterior right atrium (15 of 18) than at the lateral (8 of 18) and high right atrium (2 of 17), and was never observed at the coronary sinus. Atrial flutter was successfully terminated by overdrive atrial pacing in 15 of 18 patients, and termination was more easily obtained from the septal and posterior right atrium.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
68.
OBJECTIVES: To define the incidence, contemporary utilization patterns, efficacy, and complications of thromboembolic prophylactic treatment in patients with chronic (CAF) and paroxysmal atrial fibrillation (PAF). BACKGROUND: Although recent randomized trials with antithrombotic therapy in nonrheumatic atrial fibrillation (AF) patients emphasized the benefits of warfarin in preventing stroke, warfarin treatment is still far from optimal. METHODS: A retrospective analysis of the medical records of 506 patients with nonrheumatic PAF or CAF from 23 clinics in the north of Israel, including an interview with the patients' family physician. RESULTS: (1) The most effective treatment for preventing thromboembolic events (a reduction of 75.9%) was warfarin at an international normalized ratio (INR) intensity of 2-3. (2) After diagnosis, 26.9% of the patients were treated with warfarin. (3) During the follow-up period (not following a thromboembolic event), an additional 26.9% of the patients began treatment with warfarin. (4) Elderly patients (p<0.001), patients with limited activity of daily living (ADL) (p<0.012) or instrumental activity of daily living (IADL) (p<0.001), and patients with PAF (p<0.0001) were less likely to be treated with warfarin. (5) Three new risk factors found for thromboembolic event were limited ADL (p<0.001), limited IADL (p<0.002), and extended duration of AF (p<0.006). CONCLUSIONS: Less than optimal utilization patterns of thromboembolic prophylactic treatment with anticoagulants were found, especially regarding elderly patients, patients with limited ADL and IADL, and patients with PAF, despite the fact that their thromboembolic risk is as high or higher than that of other patients with AF.  相似文献   
69.
Ninety-two patients affected by chronic cerebrovasculopathy were treated with cytidine diphosphate choline (CDP-choline) 1000 mg/day i.m. or with placebo, in a double-blind study. Two cycles of therapy of 4 weeks each were performed, with an interval of 1 week. There were 46 patients in each group with chronic cerebrovascular diseases, and the two groups were comparable as far as mental deterioration was concerned. The following psychometric tests were administered: Toulouse-Piéron (attention to non-verbal stimuli), Randt Memory test (memory), Sandoz Clinical Assessment of Geriatrics (SCAG, measurement of the behavioral and emotional control). The comparison between the two groups revealed significant improvements in the CDP-choline group compared with the placebo group in some of the attention capabilities (decrease in the number of wrong answers at the Toulouse-Piéron test), of the mnemonic capabilities ('General Information' subtest of Randt Memory test) and behavioral capabilities (SCAG 'affective disturbances' score). No side-effects were detected in the CDP-choline group.  相似文献   
70.
Conventional definitions of left ventricular (LV) hypertrophy do not account for interindividual differences in loading conditions. We may define LV mass as inappropriately high when exceeding 128% of theoretical values predicted by gender, height(2.7), and stroke work, which explain up to 82% of the variability of LV mass in normal reference subjects. In 652 participants in the Losartan Intervention For Endpoint reduction in hypertension study without clinically overt cardiovascular disease or diabetes, we investigated whether inappropriately high LV mass is associated with relevant LV abnormalities independent of traditional definition of LV hypertrophy (ie, LV mass index >116 g/m(2) in men and >104 g/m(2) in women). The study sample was divided into three groups: patients with inappropriately high LV mass but without LV hypertrophy were compared to patients with LV hypertrophy and to patients with appropriate LV mass and without LV hypertrophy. Patients with inappropriately high but nonhypertrophic LV mass had higher body mass index and relative wall thickness, and lower LV myocardial systolic function, than patients with appropriate LV mass or patients with LV hypertrophy. In multivariate analyses, inappropriately high LV mass was independently associated with lower myocardial systolic function independent of LV hypertrophy and other covariates. Inappropriately high LV mass was also associated with prolonged isovolumic relaxation time and lower mitral E/A ratio independent of covariates. In conclusion, inappropriately high LV mass was associated with relevant, often preclinical, manifestations of cardiac disease in the absence of traditionally defined echocardiographic LV hypertrophy and concentric geometry.  相似文献   
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