1,824 research outputs found

    Three-Dimensional Self-Navigated T2 Mapping for the Detection of Acute Cellular Rejection After Orthotopic Heart Transplantation.

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    T2 mapping is a magnetic resonance imaging technique measuring T2 relaxation time, which increases with the myocardial tissue water content. Myocardial edema is a component of acute cellular rejection (ACR) after heart transplantation. This pilot study compares in heart transplantation recipients a novel high resolution 3-dimensional (3D) T2-mapping technique with standard 2-dimensional (2D) T2-mapping for ACR detection. Consecutive asymptomatic patients (n = 26) underwent both 3D T2 mapping and reference 2D T2 mapping magnetic resonance imaging on the day of endomyocardial biopsy (EMB). 3D T2 maps were obtained at an isotropic spatial resolution of 1.72 mm (voxel volume 5.1 mm(3)). 2D and 3D maps were matched anatomically, and maximum segmental T2 values were compared blinded to EMB results. In addition, all 3D T2 maps were rendered as 3D images and inspected for foci of T2 elevation. T2 values of segments from 2D and reformatted 3D T2 maps agreed (p > 0.5). The highest 2D segmental T2 values were 49.9 ± 4.0 ms (no ACR = 0R, n = 18), 48.9 ± 0.8 ms (mild ACR = 1R, n = 3), and 65.0 ms (moderate ACR = 2R). Rendered 3D T2 maps of cases with 1R showed foci with significantly elevated T2 signal (T2 = 58.2 ± 3.6 ms); 5 cases (28%) in the 0R group showed foci with increased T2 values (>2 SD above adjacent tissue) that were not visible on the 2D T2 maps. This pilot study in a small cohort suggests equivalency of standard segmental analysis between 3D and 2D T2-mapping. 3D T2 mapping provides a spatial resolution that permits detection of foci with elevated T2 in patients with mild ACR

    Real-world utilization of the pill-in-the-pocket method for terminating episodes of atrial fibrillation: data from the multinational Antiarrhythmic Interventions for Managing Atrial Fibrillation (AIM-AF) survey

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    AIMS: Atrial fibrillation (AF) is the most common sustained arrhythmia encountered in clinical practice. Episodes may stop spontaneously (paroxysmal AF); may terminate only via intervention (persistent AF); or may persist indefinitely (permanent AF) (see European and American guidelines, referenced below, for more precise definitions). Recently, there has been renewed interest in an approach to terminate AF acutely referred to as 'pill-in-the-pocket' (PITP). The PITP is recognized in both the US and European guidelines as an effective option using an oral antiarrhythmic drug for acute conversion of acute/recent-onset AF. However, how PITP is currently used has not been systematically evaluated. METHODS AND RESULTS: The recently published Antiarrhythmic Interventions for Managing Atrial Fibrillation (AIM-AF) survey included questions regarding current PITP usage, stratified by US vs. European countries surveyed, by representative countries within Europe, and by cardiologists vs. electrophysiologists. This manuscript presents the data from this planned sub-study. Our survey revealed that clinicians in both the USA and Europe consider PITP in about a quarter of their patients, mostly for recent-onset AF with minimal or no structural heart disease (guideline appropriate). However, significant deviations exist. See the Graphical abstract for a summary of the data. CONCLUSION: Our findings highlight the frequent use of PITP and the need for further physician education about appropriate and optimal use of this strategy

    Insertable cardiac monitoring results in higher rates of atrial fibrillation diagnosis and oral anticoagulation prescription after ischaemic stroke

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    Aims: After an ischaemic stroke, atrial fibrillation (AF) detection allows for improved secondary prevention strategies. This study aimed to compare AF detection and oral anticoagulant (OAC) initiation in patients with an insertable cardiac monitor (ICM) vs. external cardiac monitor (ECM) after ischaemic stroke. Methods and results: Medicare Fee-for-Service (FFS) insurance claims and Abbott Labs device registration data were used to identify patients hospitalized with an ischaemic stroke in 2017-2019 who received an ICM or ECM within 3 months. Patients with continuous Medicare FFS insurance and prescription drug enrolment in the prior year were included. Patients with prior AF, atrial flutter, cardiac devices, or OAC were excluded. Insertable cardiac monitor and ECM patients were propensity score matched 1:4 on demographics, comorbidities, and stroke hospitalization characteristics. The outcomes of interest were AF detection and OAC initiation evaluated with Kaplan-Meier and Cox proportional hazard regression analyses. A total of 5702 Medicare beneficiaries (ICM, n = 444; ECM, n = 5258) met inclusion criteria. The matched cohort consisted of 2210 Medicare beneficiaries (ICM, n = 442; ECM, n = 1768) with 53% female, mean age 75 years, and mean CHA2DS2-VASc score 4.6 (1.6). Insertable cardiac monitor use was associated with a higher probability of AF detection [(hazard ratio (HR) 2.88, 95% confidence interval (CI) (2.31, 3.59)] and OAC initiation [HR 2.91, CI (2.28, 3.72)] compared to patients monitored only with ECM. Conclusion: Patients with an ischaemic stroke monitored with an ICM were almost three times more likely to be diagnosed with AF and to be prescribed OAC compared to patients who received ECM only

    Motion-resolved fat-fraction mapping with whole-heart free-running multiecho GRE and pilot tone.

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    To develop a free-running 3D radial whole-heart multiecho gradient echo (ME-GRE) framework for cardiac- and respiratory-motion-resolved fat fraction (FF) quantification. (N <sub>TE</sub> = 8) readouts optimized for water-fat separation and quantification were integrated within a continuous non-electrocardiogram-triggered free-breathing 3D radial GRE acquisition. Motion resolution was achieved with pilot tone (PT) navigation, and the extracted cardiac and respiratory signals were compared to those obtained with self-gating (SG). After extra-dimensional golden-angle radial sparse parallel-based image reconstruction, FF, R <sub>2</sub> *, and B <sub>0</sub> maps, as well as fat and water images were generated with a maximum-likelihood fitting algorithm. The framework was tested in a fat-water phantom and in 10 healthy volunteers at 1.5 T using N <sub>TE</sub> = 4 and N <sub>TE</sub> = 8 echoes. The separated images and maps were compared with a standard free-breathing electrocardiogram (ECG)-triggered acquisition. The method was validated in vivo, and physiological motion was resolved over all collected echoes. Across volunteers, PT provided respiratory and cardiac signals in agreement (r = 0.91 and r = 0.72) with SG of the first echo, and a higher correlation to the ECG (0.1% of missed triggers for PT vs. 5.9% for SG). The framework enabled pericardial fat imaging and quantification throughout the cardiac cycle, revealing a decrease in FF at end-systole by 11.4% ± 3.1% across volunteers (p < 0.0001). Motion-resolved end-diastolic 3D FF maps showed good correlation with ECG-triggered measurements (FF bias of -1.06%). A significant difference in free-running FF measured with N <sub>TE</sub> = 4 and N <sub>TE</sub> = 8 was found (p < 0.0001 in sub-cutaneous fat and p < 0.01 in pericardial fat). Free-running fat fraction mapping was validated at 1.5 T, enabling ME-GRE-based fat quantification with N <sub>TE</sub> = 8 echoes in 6:15 min

    Single centre experience of the application of self navigated 3D whole heart cardiovascular magnetic resonance for the assessment of cardiac anatomy in congenital heart disease.

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    BACKGROUND: For free-breathing cardiovascular magnetic resonance (CMR), the self-navigation technique recently emerged, which is expected to deliver high-quality data with a high success rate. The purpose of this study was to test the hypothesis that self-navigated 3D-CMR enables the reliable assessment of cardiovascular anatomy in patients with congenital heart disease (CHD) and to define factors that affect image quality. METHODS: CHD patients ≥2 years-old and referred for CMR for initial assessment or for a follow-up study were included to undergo a free-breathing self-navigated 3D CMR at 1.5T. Performance criteria were: correct description of cardiac segmental anatomy, overall image quality, coronary artery visibility, and reproducibility of great vessels diameter measurements. Factors associated with insufficient image quality were identified using multivariate logistic regression. RESULTS: Self-navigated CMR was performed in 105 patients (55% male, 23 ± 12y). Correct segmental description was achieved in 93% and 96% for observer 1 and 2, respectively. Diagnostic quality was obtained in 90% of examinations, and it increased to 94% if contrast-enhanced. Left anterior descending, circumflex, and right coronary arteries were visualized in 93%, 87% and 98%, respectively. Younger age, higher heart rate, lower ejection fraction, and lack of contrast medium were independently associated with reduced image quality. However, a similar rate of diagnostic image quality was obtained in children and adults. CONCLUSION: In patients with CHD, self-navigated free-breathing CMR provides high-resolution 3D visualization of the heart and great vessels with excellent robustness

    Brain Computer Interfaces for inclusion

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    Patient and Physician Predictors of FFR/iFR Utilization in ACS and SIHD

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    Background Despite guidelines supporting FFR/iFR to guide PCI, these modalities remain underutilized. We sought to characterize factors associated with FFR/iFR use in patients undergoing index PCI for an acute coronary syndrome (ACS) or stable ischemic heart disease (SIHD). Methods ICD-9/10 codes were used to identify patients undergoing PCI and receiving FFR/iFR for an ACS (n=1,042,896) or SIHD (n=255,213) in a Medicare claims database from Jan. 1, 2013-June 30, 2018. Patients with functional/anatomical testing were excluded (5d prior in ACS; 60d prior in SIHD). Individuals with FFR/iFR performed 1-60 days prior to PCI were also excluded to limit analysis to non-staged procedures. Results FFR/iFR was performed the same day as PCI in 5.9% and 11.5% of patients with an ACS and SIHD, respectively. FFR/iFR was less likely to be utilized in patients that were \u3e65 years, male, and in those with diabetes, chronic kidney disease or peripheral arterial disease. Of note, a substantial proportion of physicians were non-utilizers of FFR/iFR in ACS (23.9%) and SIHD (18.6%). Use of FFR/iFR was inversely correlated with years since medical school graduation, with the lowest rate observed in physicians \u3e=31 years since graduation (Table). Conclusion This analysis highlights the underutilization of FFR/iFR. Identification of patient- and physician-factors associated with lower rates of FFR/iFR can be helpful to target areas for improvement to increase implementation of this guideline-recommended intervention
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