Use of Magnetic Resonance Direct Thrombus Imaging for the Diagnostic Management of Suspected Thrombosis in Routine Clinical Practice.

Background The noninvasive magnetic resonance direct thrombus imaging (MRDTI) technique can be used to diagnose acute deep vein thrombosis (DVT), without the use of intravenous contrast. MRDTI holds the potential to differentiate between acute and chronic DVT and could be helpful when diagnosing thrombosis is challenging. Objectives Our objective was to evaluate the application of MRDTI in clinical practice, including the frequency and indications of MRDTI scans performed in practice-based conditions, results, impact on treatment decisions, and associated patient outcomes. Methods A retrospective study was performed at the Leiden University Medical Center, the Netherlands. MRDTI scans performed since its implementation in patients aged ≥18 years as part of clinical practice for the diagnostic management of suspected thrombosis were evaluated. Results Between October 2015 and September 2023, 36 patients had undergone MRDTI for the diagnostic evaluation of thrombosis. MRDTI application increased since 2019 (five-eight scans per year). The most common indication was to differentiate between acute and chronic thrombosis, mainly for suspected recurrent ipsilateral DVT after inconclusive compression ultrasonography. In over a third of patients, acute thrombosis was confirmed by MRDTI. MRDTI results determined treatment decisions in all except two patients. One patient had symptomatic thrombosis of the lower extremity within 3 months after an MRDTI of the upper extremity without signs of acute thrombosis (1/23; 4.3%, 95% confidence interval: 0.77-21). Conclusion Over the past 4 years, MRDTI has been used increasingly in our hospital. MRDTI results guided treatment decisions, which confirms the clinical impact and feasibility of its application in daily practice.

Computed tomography diagnosis of pulmonary infarction in acute pulmonary embolism.

INTRODUCTION: Pulmonary infarction is a common sequela of pulmonary embolism (PE) but lacks a diagnostic reference standard. CTPA in the setting of acute PE does not reliably differentiate infarction from other consolidations, such as reversible alveolar hemorrhage or atelectasis. We aimed to assess the diagnostic accuracy for recognizing pulmonary infarction on CT in the acute phase of PE, with follow-up CT as reference. MATERIALS AND METHODS: Initial and follow-up CT scans of 33 patients with acute PE were retrospectively assessed. Two radiologists independently evaluated the presence and size of suspected pulmonary infarction on the initial CT. Confirmation of infarction was established by detection of residual densities on follow-up CT. Sensitivity, specificity and interobserver variability were calculated. RESULTS: In total, 60 presumed infarctions were found in 32 patients, of which 34 infarctions in 21 patients could be confirmed at follow-up. On patient-level, observers' sensitivity/specificity were 91 %/9 %, and 73 %/46 %, respectively, with interobserver agreement by Kappa's coefficient of 0.17. Confirmed infarctions were usually larger than false positive lesions (median approximate volume of 6.6 mL [IQR 0.84-21.3] vs. 1.3 mL [IQR 0.57-6.5], p = 0.040), but still small. An occluding thrombus in a supplying vessel was predictive for confirmed infarction (OR 11, 95%CI 2.1-55), but was not discriminative. CONCLUSIONS: Pulmonary infarction is a common finding in acute PE, and generally small. Radiological identification of infarction was challenging, with considerable interobserver variability. Complete obstruction of the supplying (sub)segmental pulmonary artery was found as the strongest predictor for pulmonary infarction but was not demonstrated to be discriminative.

Modern imaging of acute pulmonary embolism.

The first-choice imaging test for visualization of thromboemboli in the pulmonary vasculature in patients with suspected acute pulmonary embolism (PE) is multidetector computed tomography pulmonary angiography (CTPA) - a readily available and widely used imaging technique. Through technological advancements over the past years, alternative imaging techniques for the diagnosis of PE have become available, whilst others are still under investigation. In particular, the evolution of artificial intelligence (AI) is expected to enable further innovation in diagnostic management of PE. In this narrative review, current CTPA techniques and the emerging technology photon-counting CT (PCCT), as well as other modern imaging techniques of acute PE are discussed, including CTPA with iodine maps based on subtraction or dual-energy acquisition, single-photon emission CT (SPECT), magnetic resonance angiography (MRA), and magnetic resonance direct thrombus imaging (MRDTI). Furthermore, potential applications of AI are discussed.

Relation between Coronary Artery Calcium Score and Cardiovascular Events in Hodgkin Lymphoma Survivors: A Cross-Sectional Matched Cohort Study.

BACKGROUND: Thoracic radiotherapy is one of the corner stones of HL treatment, but it is associated with increased risk of cardiovascular events. As HL is often diagnosed at a young age, long-term follow-up including screening for coronary artery disease (CAD) is recommended. OBJECTIVES: This study aims to evaluate the presence of coronary artery calcium score (CACS) in relation to cardiovascular events in HL patients treated with thoracic radiotherapy compared to a non-cancer control group. METHODS: Consecutive HL patients who underwent evaluation for asymptomatic CAD with coronary computed tomography angiography > 10 years after thoracic irradiation were included. The study population consisted of 97 HL patients matched to 97 non-cancer patients on gender, age, cardiovascular risk factors, and statin use. RESULTS: Mean age during CT scan in the HL population was 45.5 ± 9.9 and in the non-cancer population 45.5 ± 10.3 years. CACS was elevated (defined as >0) in 49 (50.5%) HL patients and 30 (30.9%) control patients. HL survivors had an odds ratio of 2.28 [95% CI: 1.22-4.28] for having a CACS > 0 compared to the matched population (p = 0.006). Prevalence of CACS > 90th percentile differed significantly: 17.1% in HL survivors vs. 4.6% in the matched population (p = 0.009). Non-obstructive coronary artery stenosis was more prevalent in the HL population than in the control population (45.7% vs. 28.4%, respectively, p = 0.01). During follow-up of 8.5 [5.3; 9.9] years, nine HL patients experienced an event including two patients with a CACS of zero. No events occurred in the control population. CONCLUSION: In a matched study population, HL survivors have a higher prevalence of a CACS > 0 and an increased risk of cardiovascular events after thoracic irradiation compared to a matched non-cancer control group.

Genetic variant in the BRAF gene compatible with Noonan spectrum disorders in an adult Fontan patient with refractory protein losing enteropathy: a follow-up report.

Background: Patients with a univentricular heart form a morphological heterogenous group of patients at the most severe end of the congenital heart disease (CHD) spectrum. Over the past decades, more awareness and knowledge has been raised on the genetic contributions to CHD. To date, only a limited number of genes have been identified in the hypoplastic heart, mainly in left-sided hypoplasia. There is still much more to be elucidated in this field. Case summary: Here, we present a follow-up report of a case of an adult patient after Fontan palliation, born with a.o. tricuspid atresia with hypoplastic right ventricle and pulmonary stenosis. This patient encountered a myriad of late sequalae involving multiple organ systems during the course of his young adult life, including refractory protein losing enteropathy (PLE). Concomitant extracardiac anomalies, in addition to the complex CHD and its complications, prompted for genetic evaluation. Whole exome sequencing showed a variant of uncertain significance in the BRAF gene [NM_004333.4:c.1897T > C p.(Tyr633His)], associated with Noonan spectrum disorders, that is also infamous for lymphoedema and PLE. The variant regards an evolutionarily highly conserved amino acid and is assumed pathogenic according to all prediction programmes. The mutation was most likely de novo. Discussion: Genetic screening can provide new insights in the complex and varied phenotype of the (adult) Fontan patient and in the myriad of complications encountered. Adult CHD cardiologists should be aware of genetic syndromes underlying a CHD, concomitant extracardiac anomalies, and a complex clinical course with a broad spectrum of late sequelae.

Diagnostic performance of eNose technology in COVID-19 patients after hospitalization.

BACKGROUND: Volatile organic compounds (VOCs) produced by human cells reflect metabolic and pathophysiological processes which can be detected with the use of electronic nose (eNose) technology. Analysis of exhaled breath may potentially play an important role in diagnosing COVID-19 and stratification of patients based on pulmonary function or chest CT. METHODS: Breath profiles of COVID-19 patients were collected with an eNose device (SpiroNose) 3 months after discharge from the Leiden University Medical Centre and matched with breath profiles from healthy individuals for analysis. Principal component analysis was performed with leave-one-out cross validation and visualised with receiver operating characteristics. COVID-19 patients were stratified in subgroups with a normal pulmonary diffusion capacity versus patients with an impaired pulmonary diffusion capacity (DLCOc < 80% of predicted) and in subgroups with a normal chest CT versus patients with COVID-19 related chest CT abnormalities. RESULTS: The breath profiles of 135 COVID-19 patients were analysed and matched with 174 healthy controls. The SpiroNose differentiated between COVID-19 after hospitalization and healthy controls with an AUC of 0.893 (95-CI, 0.851-0.934). There was no difference in VOCs patterns in subgroups of COVID-19 patients based on diffusion capacity or chest CT. CONCLUSIONS: COVID-19 patients have a breath profile distinguishable from healthy individuals shortly after hospitalization which can be detected using eNose technology. This may suggest ongoing inflammation or a common repair mechanism. The eNose could not differentiate between subgroups of COVID-19 patients based on pulmonary diffusion capacity or chest CT.

Impact of pulmonary infarction in pulmonary embolism on presentation and outcomes.

BACKGROUND: Pulmonary infarction (PI) is relatively common in pulmonary embolism (PE). The association between PI and persistent symptoms or adverse events is largely unknown. AIM: To evaluate the predictive value of radiological PI signs at acute PE diagnosis on 3-month outcomes. METHODS: We studied a convenience cohort with computed tomography pulmonary angiography (CTPA)-confirmed PE for whom extensive 3-month follow-up data were available. The CTPAs were re-evaluated for signs of suspected PI. Associations with presenting symptoms, adverse events (recurrent thrombosis, PE-related readmission and mortality) and self-reported persistent symptoms (dyspnea, pain and post-PE functional impairment) at 3-month follow-up were investigated using univariate Cox regression analysis. RESULTS: At re-evaluation of the CTPAs, 57 of 99 patients (58 %) had suspected PI, comprising a median of 1 % (IQR 1-3) of total lung parenchyma. Patients with suspected PI more often presented with hemoptysis (11 % vs. 0 %) and pleural pain (OR 2.7, 95%CI 1.2-6.2), and with more proximal PE on CTPA (OR 1.6, 95%CI 1.1-2.4) than patients without suspected PI. There was no association with adverse events, persistent dyspnea or pain at 3-month follow-up, but signs of PI predicted more functional impairment (OR 3.03, 95%CI 1.01-9.13). Sensitivity analysis with the largest infarctions (upper tertile of infarction volume) yielded similar results. CONCLUSIONS: PE patients radiologically suspected of PI had a different clinical presentation than patients without those signs and reported more functional limitations after 3 months of follow-up, a finding that could guide patient counselling.

Coronary calcium score in COVID-19 survivors: Association with cardiac injury and cardiac function after 6 weeks.

Aims: Cardiac manifestations are common in COVID-19, often elevated serum troponin levels or myocardial dysfunction on trans-thoracic echocardiography (TTE) is observed. Both parameters are associated with increased in-hospital mortality. Possibly, subclinical coronary atherosclerosis plays a role, of which severity can be assessed by calculating the coronary artery calcium (CAC) score. This study aims to determine the relation between coronary atherosclerosis and cardiac manifestations in COVID-19 survivors. Methods: This study was conducted at the Leiden University Medical Center. All patients admitted for COVID-19 were included and scheduled for a 6-week follow-up visit with trans-thoracic echocardiography (TTE). CAC was assessed according to an ordinal score on non-gated, non-contrast enhanced computed tomography of the chest. Patients with and without CAC were compared on cardiac injury as reflected by elevated serum troponin levels and impaired cardiac function assessed through TTE. Results: In total, 146 patients were included. Mean age was 62 years and 62 % of the patients were male. During admission, patients with CAC showed significantly higher levels of troponin (19 ng/L vs 10 ng/L; p < 0.01). Overall, mild echocardiographic abnormalities were seen; 12 % showed reduced left ventricular function (left ventricular ejection fraction of <50 %) and 14 % reduced right ventricular function (tricuspid annular planar systolic excursion ≤17 mm). Following multivariable adjustments, there was no significant relation between CAC and myocardial function at 6 weeks. Conclusion: The present study shows that coronary atherosclerosis is associated with cardiac injury in COVID-19 survivors. However, no significant relation with impaired cardiac function was demonstrated.

Fibrotic-like abnormalities notably prevalent one year after hospitalization with COVID-19.

BACKGROUND: We investigated whether COVID-19 leads to persistent impaired pulmonary function, fibrotic-like abnormalities or psychological symptoms 12 months after discharge and whether severely ill patients (ICU admission) recover differently than moderately ill patients. METHODS: This single-centre cohort study followed adult COVID-19 survivors for a period of one year after discharge. Patients underwent pulmonary function tests 6 weeks, 3 months and 12 months after discharge and were psychologically evaluated at 6 weeks and 12 months. Computed tomography (CT) was performed after 3 months and 12 months. RESULTS: 66 patients were analysed, their median age was 60.5 (IQR: 54-69) years, 46 (70%) patients were male. 38 (58%) patients had moderate disease and 28 (42%) patients had severe disease. Most patients had spirometric values within normal range after 12 months of follow-up. 12 (23%) patients still had an impaired lung diffusion after 12 months. Impaired pulmonary diffusion capacity was associated with residual CT abnormalities (OR 5.1,CI-95: 1.2-22.2), shortness of breath (OR 7.0, CI-95: 1.6-29.7) and with functional limitations (OR 5.8, CI-95: 1.4-23.8). Ground-glass opacities resolved in most patients during follow-up. Resorption of reticulation, bronchiectasis and curvilinear bands was rare and independent of disease severity. 81% of severely ill patients and 37% of moderately ill patients showed residual abnormalities after 12 months (OR 8.1, CI-95: 2.5-26.4). A minority of patients had symptoms of post-traumatic stress disorder, anxiety, depression and cognitive failure during follow-up. CONCLUSION: Some patients still had impaired lung diffusion 12 months after discharge and fibrotic-like residual abnormalities were notably prevalent, especially in severely ill patients.

A percutaneous treatment strategy of an adult patient with a bicuspid aortic valve, coarctation of the aorta, and an exceptionally large aneurysm of a collateral artery: Case report and literature overview.

Coarctation of the aorta (CoA) is a congenital heart defect that is associated with a bicuspid aortic valve (BAV), ascending aorta dilatation, intracerebral aneurysms, and premature atherosclerotic disease. The first presentation during late adulthood is rare and is frequently driven by late sequelae. Hypertrophic collateral arteries can develop aneurysms which are at risk for spontaneous rupture, however, treatment recommendations for these aneurysms are scarce. Here, we describe the clinical course and percutaneous treatment strategy of a patient with a late diagnosis of a pin-point CoA, a BAV with moderate regurgitation, and an exceptionally large aneurysm of a collateral artery. A 59-year-old woman was diagnosed with Streptococcus bovis endocarditis of a BAV with moderate aortic valve regurgitation and small vegetation (<5 mm) on the non-coronary cusp. Work-up revealed hypertension and adenocarcinoma in situ of the ascending colon, considered the bacteremia porte d'entrée, for which a curative hemicolectomy was performed. Echocardiography showed a narrowing of the aorta distal from the origin of the left subclavian artery with the antegrade diastolic flow with a pathognomonic "sawtooth" pattern and an estimated pressure gradient of >70 mmHg. Computed tomography angiography (CTA) showed a network of well-developed collateral arteries and a levoatriocardinal vein. One of the collateral arteries arising from the left subclavian artery revealed an exceptionally large aneurysmatic dilation (29 × 24 × 24 mm). The invasive assessment confirmed a hemodynamically significant CoA. Treatment involved balloon dilatation and placement of a covered stent at the site of the pin-point CoA and a percutaneous coronary intervention (PCI) of the stenosis in the left anterior descending artery. No residual gradient over the CoA was observed. Antihypertensive drugs could be discontinued, and CTA performed 4 months later showed regression and thrombosis of the numerous collaterals and, importantly, thrombosis of the large aneurysm. This case illustrates the late diagnosis of CoA with associated congenital heart defects and late sequelae including hypertension, BAV endocarditis, coronary artery disease, and aneurysm formation of the extensive collateral network. The patient underwent pharmacological and percutaneous treatment, ultimately resulting in the alleviation of the CoA, normalization of the blood pressure, reduction of collateral flow, and thrombosis of the large aneurysm of the collateral artery.

Endobronchial ultrasound for T4 staging in patients with resectable NSCLC.

BACKGROUND: In lung cancer patients, accurate assessment of mediastinal and vascular tumor invasion (stage T4) is crucial for optimal treatment allocation and to prevent unnecessary thoracotomies. We assessed the diagnostic accuracy of linear endobronchial ultrasound (EBUS) for T4-status in patients with centrally located lung cancer. METHODS: This is a retrospective study among consecutive patients who underwent EBUS for diagnosis and staging of lung cancer in four hospitals in The Netherlands (Amsterdam, Leiden), Italy (Bologna) and Poland (Zakopane) between 04-2012 and 04-2019. Patients were included if the primary tumor was detected by EBUS and subsequent surgical-pathological staging was performed, which served as the reference standard. T4-status was extracted from EBUS and pathology reports. Chest CT's were re-reviewed for T4-status. RESULTS: 104 patients with lung cancer in whom EBUS detected the primary tumour, and who underwent subsequent surgical-pathological staging were included. 36 patients (35 %) had T4-status, based on vascular (n = 17), mediastinal (n = 15), both vascular and mediastinal (n = 3), or oesophageal invasion (n = 1). For EBUS, sensitivity, specificity, PPV and NPV for T4-status were (n = 104): 63.9 % (95 %CI 46.2-79.2 %), 92.6 % (83.7-97.6 %), 82.1 % (65.6-91.7 %), and 82.9 % (75.7-88.2 %), respectively. For chest CT (n = 72): 61.5 % (95 %CI 40.6-79.8 %), 37.0 % (23.2-52.5 %), 35.6 % (27.5-44.6 %), and 63.0 % (47.9-75.9 %), respectively. When combining CT and EBUS with concordant T4 status (n = 33): 90.9 % (95 %CI 58.7-99.8 %), 77.3 % (54.6-92.20 %), 66.7 % (47.5-81.6 %), and 94.4 % (721-99.1%), respectively. CONCLUSION: Both EBUS and CT alone are inaccurate for assessing T4-status as standalone test. However, combining a negative EBUS with a negative CT may rule out T4-status with high certainty.

Coronary Artery Calcification as a Marker for Coronary Artery Stenosis: Comparing Kidney Failure to the General Population.

RATIONALE & OBJECTIVE: The presence of calcified plaques in the coronary arteries is associated with cardiovascular mortality and is a hallmark of chronic kidney failure, but it is unclear whether this is associated with the same degree of coronary artery stenosis as in patients without kidney disease. We compared the relationship of coronary artery calcification (CAC) and stenosis between dialysis patients and patients without chronic kidney disease (CKD). STUDY DESIGN: Observational cohort study. SETTING & PARTICIPANTS: 127 dialysis patients and 447 patients without CKD with cardiovascular risk factors underwent cardiac computed tomography (CT), consisting of non-contrast-enhanced CT and CT angiography. CAC score and degree of coronary artery stenosis were assessed by independent readers. PREDICTOR: Dialysis treatment. OUTCOME: Association between calcification and stenosis. ANALYTICAL APPROACH: Logistic regression to determine the association between CAC score and the presence of stenosis in a matched cohort and, in the full cohort, testing for the interaction of dialysis status with this relationship. RESULTS: 112 patients were matched from each cohort, totaling 224 patients, using propensity scores for dialysis, balancing numerous cardiovascular risk factors. Median CAC score was 210 (IQR, 19-859) in dialysis patients and 58 (IQR, 0-254) in patients without CKD; 35% of dialysis patients and 36% of patients without CKD had coronary artery stenosis ≥ 50%. Per each 100-unit higher CAC score, the matched dialysis cohort had significantly lower ORs for stenosis than the non-CKD cohort, 0.67 (95% CI, 0.52-0.83) for stenosis ≥ 50% and 0.75 (95% CI, 0.62-0.90) for stenosis ≥ 70%. LIMITATIONS: No comparison with the gold standard fractional flow reserve. CONCLUSIONS: Dialysis patients have higher risk for coronary artery stenosis with higher CAC scores, but this risk is comparatively lower than in patients without CKD with similar CAC scores. In dialysis patients, a high CAC score can easily be found without significant stenosis. Our data enable "translation" of degree of calcification to the probability of coronary stenosis in dialysis patients.

Detection of upper extremity deep vein thrombosis by magnetic resonance non-contrast thrombus imaging.

BACKGROUND: Compression ultrasonography (CUS) is the first-line imaging test for diagnosing upper extremity deep vein thrombosis (UEDVT), but often yields inconclusive test results. Contrast venography is still considered the diagnostic standard but is an invasive technique. OBJECTIVES: We aimed to determine the diagnostic accuracy of magnetic resonance noncontrast thrombus imaging (MR-NCTI) for the diagnosis of UEDVT. METHODS: In this international multicenter diagnostic study, we prospectively included patients with clinically suspected UEDVT who were managed according to a diagnostic algorithm that included a clinical decision rule (CDR), D-dimer test, and diagnostic imaging. UEDVT was confirmed by CUS or (computed tomography [CT]) venography. UEDVT was excluded by (1) an unlikely CDR and normal D-dimer, (2) a normal serial CUS or (3) a normal (CT) venography. Within 48 h after the final diagnosis was established, patients underwent MR-NCTI. MR-NCTI images were assessed post hoc by two independent radiologists unaware of the presence or absence of UEDVT. The sensitivity, specificity, and interobserver agreement of MR-NCTI for UEDVT were determined. RESULTS: Magnetic resonance noncontrast thrombus imaging demonstrated UEDVT in 28 of 30 patients with UEDVT and was normal in all 30 patients where UEDVT was ruled out, yielding a sensitivity of 93% (95% CI 78-99) and specificity of 100% (95% CI 88-100). The interobserver agreement of MR-NCTI had a kappa value of 0.83 (95% CI 0.69-0.97). CONCLUSIONS: Magnetic resonance noncontrast thrombus imaging is an accurate and reproducible method for diagnosing UEDVT. Clinical outcome studies should determine whether MR-NCTI can replace venography as the second-line imaging test in case of inconclusive CUS.

The Clinical Spectrum of Kommerell's Diverticulum in Adults with a Right-Sided Aortic Arch: A Case Series and Literature Overview.

BACKGROUND: Kommerell's diverticulum is a rare vascular anomaly characterized as an outpouch at the onset of an aberrant subclavian artery. In the variant of a right-sided aortic arch, the trachea and esophagus are enclosed dorsally by the arch. In the configuration of an aberrant left subclavian artery, a Kommerell's diverticulum and persisting ductus arteriosus or ductal ligament enclose the lateral side, forming a vascular ring which may result in (symptomatic) esophageal or tracheal compression. Spontaneous rupture of an aneurysmatic Kommerell's diverticulum has also been reported. Due to the rarity of this condition and underreporting in the literature, the clinical implications of a Kommerell's diverticulum are not well defined. CASE SUMMARY: We describe seven consecutive adult patients with a right-sided aortic arch and an aberrant course of the left subclavian artery (arteria lusoria), and a Kommerell's diverticulum, diagnosed in our tertiary hospital. One patient had severe symptoms related to the Kommerell's diverticulum and underwent surgical repair. In total, two of the patients experienced mild non-limiting dyspnea complaints and in four patients the Kommerell's diverticulum was incidentally documented on a computed tomography (CT) scan acquired for a different indication. The size of the Kommerell's diverticulum ranged from 19 × 21 mm to 30 × 29 mm. In the six patients that did not undergo surgery, a strategy of periodic follow-up with structural imaging was pursued. No significant growth of the Kommerell's diverticulum was observed and none of the patients experienced an acute aortic syndrome to date. DISCUSSION: Kommerell's diverticulum in the setting of a right-sided aortic arch with an aberrant left subclavian artery is frequently associated with tracheal and esophageal compression and this may result in a varying range of symptoms. Guidelines on management of Kommerell's diverticulum are currently lacking. This case series and literature overview suggests that serial follow-up is warranted in adult patients with a Kommerell's diverticulum with small dimensions and no symptoms, however, that surgical intervention should be considered when patients become symptomatic or when the diameter exceeds 30 mm in the absence of symptoms.

Short-term outpatient follow-up of COVID-19 patients: A multidisciplinary approach.

BACKGROUND: Short-term follow-up of COVID-19 patients reveals pulmonary dysfunction, myocardial damage and severe psychological distress. Little is known of the burden of these sequelae, and there are no clear recommendations for follow-up of COVID-19 patients.In this multi-disciplinary evaluation, cardiopulmonary function and psychological impairment after hospitalization for COVID-19 are mapped. METHODS: We evaluated patients at our outpatient clinic 6 weeks after discharge. Cardiopulmonary function was measured by echocardiography, 24-hours ECG monitoring and pulmonary function testing. Psychological adjustment was measured using questionnaires and semi-structured clinical interviews. A comparison was made between patients admitted to the general ward and Intensive care unit (ICU), and between patients with a high versus low functional status. FINDINGS: Eighty-one patients were included of whom 34 (41%) had been admitted to the ICU. New York Heart Association class II-III was present in 62% of the patients. Left ventricular function was normal in 78% of patients. ICU patients had a lower diffusion capacity (mean difference 12,5% P = 0.01), lower forced expiratory volume in one second and forced vital capacity (mean difference 14.9%; P<0.001; 15.4%; P<0.001; respectively). Risk of depression, anxiety and PTSD were 17%, 5% and 10% respectively and similar for both ICU and non-ICU patients. INTERPRETATION: Overall, most patients suffered from functional limitations. Dyspnea on exertion was most frequently reported, possibly related to decreased DLCOc. This could be caused by pulmonary fibrosis, which should be investigated in long-term follow-up. In addition, mechanical ventilation, deconditioning, or pulmonary embolism may play an important role.

Chest CT in the Emergency Department for Diagnosis of COVID-19 Pneumonia: Dutch Experience.

Background Clinicians need to rapidly and reliably diagnose coronavirus disease 2019 (COVID-19) for proper risk stratification, isolation strategies, and treatment decisions. Purpose To assess the real-life performance of radiologist emergency department chest CT interpretation for diagnosing COVID-19 during the acute phase of the pandemic, using the COVID-19 Reporting and Data System (CO-RADS). Materials and Methods This retrospective multicenter study included consecutive patients who presented to emergency departments in six medical centers between March and April 2020 with moderate to severe upper respiratory symptoms suspicious for COVID-19. As part of clinical practice, chest CT scans were obtained for primary work-up and scored using the five-point CO-RADS scheme for suspicion of COVID-19. CT was compared with severe acute respiratory syndrome coronavirus 2 reverse-transcription polymerase chain reaction (RT-PCR) assay and a clinical reference standard established by a multidisciplinary group of clinicians based on RT-PCR, COVID-19 contact history, oxygen therapy, timing of RT-PCR testing, and likely alternative diagnosis. Performance of CT was estimated using area under the receiver operating characteristic curve (AUC) analysis and diagnostic odds ratios against both reference standards. Subgroup analysis was performed on the basis of symptom duration grouped presentations of less than 48 hours, 48 hours through 7 days, and more than 7 days. Results A total of 1070 patients (median age, 66 years; interquartile range, 54-75 years; 626 men) were included, of whom 536 (50%) had a positive RT-PCR result and 137 (13%) of whom were considered to have a possible or probable COVID-19 diagnosis based on the clinical reference standard. Chest CT yielded an AUC of 0.87 (95% CI: 0.84, 0.89) compared with RT-PCR and 0.87 (95% CI: 0.85, 0.89) compared with the clinical reference standard. A CO-RADS score of 4 or greater yielded an odds ratio of 25.9 (95% CI: 18.7, 35.9) for a COVID-19 diagnosis with RT-PCR and an odds ratio of 30.6 (95% CI: 21.1, 44.4) with the clinical reference standard. For symptom duration of less than 48 hours, the AUC fell to 0.71 (95% CI: 0.62, 0.80; P < .001). Conclusion Chest CT analysis using the coronavirus disease 2019 (COVID-19) Reporting and Data System enables rapid and reliable diagnosis of COVID-19, particularly when symptom duration is greater than 48 hours. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Elicker in this issue.

Automated Assessment of COVID-19 Reporting and Data System and Chest CT Severity Scores in Patients Suspected of Having COVID-19 Using Artificial Intelligence.

Background The coronavirus disease 2019 (COVID-19) pandemic has spread across the globe with alarming speed, morbidity, and mortality. Immediate triage of patients with chest infections suspected to be caused by COVID-19 using chest CT may be of assistance when results from definitive viral testing are delayed. Purpose To develop and validate an artificial intelligence (AI) system to score the likelihood and extent of pulmonary COVID-19 on chest CT scans using the COVID-19 Reporting and Data System (CO-RADS) and CT severity scoring systems. Materials and Methods The CO-RADS AI system consists of three deep-learning algorithms that automatically segment the five pulmonary lobes, assign a CO-RADS score for the suspicion of COVID-19, and assign a CT severity score for the degree of parenchymal involvement per lobe. This study retrospectively included patients who underwent a nonenhanced chest CT examination because of clinical suspicion of COVID-19 at two medical centers. The system was trained, validated, and tested with data from one of the centers. Data from the second center served as an external test set. Diagnostic performance and agreement with scores assigned by eight independent observers were measured using receiver operating characteristic analysis, linearly weighted κ values, and classification accuracy. Results A total of 105 patients (mean age, 62 years ± 16 [standard deviation]; 61 men) and 262 patients (mean age, 64 years ± 16; 154 men) were evaluated in the internal and external test sets, respectively. The system discriminated between patients with COVID-19 and those without COVID-19, with areas under the receiver operating characteristic curve of 0.95 (95% CI: 0.91, 0.98) and 0.88 (95% CI: 0.84, 0.93), for the internal and external test sets, respectively. Agreement with the eight human observers was moderate to substantial, with mean linearly weighted κ values of 0.60 ± 0.01 for CO-RADS scores and 0.54 ± 0.01 for CT severity scores. Conclusion With high diagnostic performance, the CO-RADS AI system correctly identified patients with COVID-19 using chest CT scans and assigned standardized CO-RADS and CT severity scores that demonstrated good agreement with findings from eight independent observers and generalized well to external data. © RSNA, 2020 Supplemental material is available for this article.