Value CMR: Towards a comprehensive, rapid, cost-effective cardiovascular magnetic resonance imaging

Cardiac magnetic resonance imaging (CMR) is considered the gold standard for measuring cardiac function. Further, in a single CMR exam, information about cardiac structure, tissue composition, and blood flow could be obtained. Nevertheless, CMR is underutilized due to long scanning times, the need for multiple breath-holds, use of a contrast agent, and relatively high cost. In this work, we propose a rapid, comprehensive, contrast-free CMR exam that does not require repeated breath-holds, based on recent developments in imaging sequences. Time-consuming conventional sequences have been replaced by advanced sequences in the proposed CMR exam. Specifically, conventional 2D cine and phase-contrast (PC) sequences have been replaced by optimized 3D-cine and 4D-flow sequences, respectively. Furthermore, conventional myocardial tagging has been replaced by fast strain-encoding (SENC) imaging. Finally, T1 and T2 mapping sequences are included in the proposed exam, which allows for myocardial tissue characterization. The proposed rapid exam has been tested in vivo. The proposed exam reduced the scan time from \u3e1 hour with conventional sequences to \u3c20 minutes. Corresponding cardiovascular measurements from the proposed rapid CMR exam showed good agreement with those from conventional sequences and showed that they can differentiate between healthy volunteers and patients. Compared to 2D cine imaging that requires 12-16 separate breath-holds, the implemented 3D-cine sequence allows for whole heart coverage in 1-2 breath-holds. The 4D-flow sequence allows for whole-chest coverage in less than 10 minutes. Finally, SENC imaging reduces scan time to only one slice per heartbeat. In conclusion, the proposed rapid, contrast-free, and comprehensive cardiovascular exam does not require repeated breath-holds or to be supervised by a cardiac imager. These improvements make it tolerable by patients and would help improve cost effectiveness of CMR and increase its adoption in clinical practice

Intra-individual comparison of coronary calcium scoring between photon counting detector- and energy integrating detector-CT : effects on risk reclassification

Purpose: To compare coronary artery calcium volume and score (CACS) between photon-counting detector (PCD) and conventional energy integrating detector (EID) computed tomography (CT) in a phantom and prospective patient study. Methods: A commercially available CACS phantom was scanned with a standard CACS protocol (120 kVp, slice thickness/increment 3/1.5 mm, and a quantitative Qr36 kernel), with filtered back projection on the EID-CT, and with monoenergetic reconstruction at 70 keV and quantum iterative reconstruction off on the PCD-CT. The same settings were used to prospectively acquire data in patients (n = 23, 65 ± 12.1 years), who underwent PCD- and EID-CT scans with a median of 5.5 (3.0–12.5) days between the two scans in the period from August 2021 to March 2022. CACS was quantified using a commercially available software solution. A regression formula was obtained from the aforementioned comparison and applied to simulate risk reclassification in a pre-existing cohort of 514 patients who underwent a cardiac EID-CT between January and December 2021. Results: Based on the phantom experiment, CACSPCD–CT showed a more accurate measurement of the reference CAC volumes (overestimation of physical volumes: PCD-CT 66.1 ± 1.6% vs. EID-CT: 77.2 ± 0.5%). CACSEID–CT and CACSPCD–CT were strongly correlated, however, the latter measured significantly lower values in the phantom (CACSPCD–CT: 60.5 (30.2–170.3) vs CACSEID–CT 74.7 (34.6–180.8), p = 0.0015, r = 0.99, mean bias –9.7, Limits of Agreement (LoA) –36.6/17.3) and in patients (non-significant) (CACSPCD–CT: 174.3 (11.1–872.7) vs CACSEID–CT 218.2 (18.5–876.4), p = 0.10, r = 0.94, mean bias –41.1, LoA –315.3/232.5). The systematic lower measurements of Agatston score on PCD-CT system led to reclassification of 5.25% of our simulated patient cohort to a lower classification class. Conclusion: CACSPCD–CT is feasible and correlates strongly with CACSEID–CT, however, leads to lower CACS values. PCD-CT may provide results that are more accurate for CACS than EID-CT

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication

Pictorial essay: Orbital tuberculosis

Tuberculosis of the orbit is rare, even in places where tuberculosis is endemic. The disease may involve soft tissue, the lacrimal gland, or the periosteum or bones of the orbital wall. Intracranial extension, in the form of extradural abscess, and infratemporal fossa extension has been described. This pictorial essay illustrates the imaging findings of nine histopathologically confirmed cases of orbital tuberculosis. All these patients responded to antituberculous treatment

Intracranial blastomycosis mimicking high-grade neoplasm on magnetic resonance imaging and spectroscopy

We describe a case of posterior fossa blastomycosis in an immunocompetent patient that mimicked high-grade neoplasm on neuroimaging. Histological analysis confirmed blastomycosis. Because the neuroimaging characteristics of intracerebral blastomycosis can be confused for neoplasm, these lesions must be confirmed histologically before initiating aggressive treatment for presumptive high-grade neoplasm. To our knowledge, it is the first description of a neoplasm mimic on MRS in the setting of intracranial blastomycosis

Correlation of computed tomography test bolus dynamics and conventional computed tomography parameters with pulmonary vascular resistance in patients with pulmonary arterial hypertension

OBJECTIVE: Pulmonary vascular resistance (PVR) is a measurement obtained with invasive right heart catheterization (RHC) that is commonly used for management of patients with pulmonary arterial hypertension (PAH). Computed tomography pulmonary angiography (CTPA) is also done as part of the workup for PAH in some cases. The aim of our study was to assess the correlation of contrast dynamic changes in the main pulmonary artery (MPA) on CTPA with PVR obtained with RHC. METHODS: This is an IRB-approved retrospective study performed in two separate institutions (Medical College of Wisconsin and University of Alabama) between January 2010 and December 2013. During CTPA done as test bolus, serial images are acquired at the level of MPA after intravenous injection of contrast to determine timing of the CT acquisition. Since the PVR changes with the degree of PAH, we hypothesize that will be reflected in the contrast kinetics in MPA. A correlation of standard CT metrics (MPA diameter, right pulmonary artery [PA] diameter, left PA diameter, MPA/aorta ratio, and right ventricle/left ventricle [RV/LV] ratio) and dynamic (full width at half maximum) CTPA parameters in patients with known PAH was performed with PVR obtained from RHC done within 30 days. Statistical analysis was performed by Pearson correlation coefficient. RESULTS: Among 221 patients in our database, 37 patients fulfilled the selection criteria. There was a strong correlation between full width half maximum (FWHM) and mean pulmonary artery pressure (mPAP) (r=0.69, p value\u3c0.00001), PVR (r=0.8, p value\u3c0.00001) and indexed PVR (PVRI) (r=0.75, p value\u3c0.00001). CONCLUSION: FWHM obtained from CTPA strongly correlates with RHC parameters and is potentially more helpful than static measurements for follow-up of patients with known PAH to assess response to treatment or progression

Pictorial essay: Orbital tuberculosis

Tuberculosis of the orbit is rare, even in places where tuberculosis is endemic. The disease may involve soft tissue, the lacrimal gland, or the periosteum or bones of the orbital wall. Intracranial extension, in the form of extradural abscess, and infratemporal fossa extension has been described. This pictorial essay illustrates the imaging findings of nine histopathologically confirmed cases of orbital tuberculosis. All these patients responded to antituberculous treatment