Association of cardiometabolic and vascular atherosclerosis phenotypes on non-contrast chest CT with incident heart failure in patients with severe hypercholesterolemia.

BACKGROUND: Coronary artery calcium (CAC), thoracic aorta calcification (TAC), non-alcoholic fatty liver disease (NAFLD), and epicardial adipose tissue (EAT) are associated with atherosclerotic cardiovascular disease (ASCVD) and heart failure (HF). OBJECTIVES: We aimed to determine whether these cardiometabolic and atherosclerotic risk factors identified by non-contrast chest computed tomography (CT) are associated with HF hospitalizations in patients with LDL-C≥ 190 mg/dL. METHODS: We conducted a retrospective cohort analysis of patients with LDL-C ≥190 mg/dL, aged ≥40 years without established ASCVD or HF, who had a non-contrast chest CT within 3 years of LDL-C measurement. Ordinal CAC, ordinal TAC, EAT, and NAFLD were measured. Kaplan-Meier curves and multivariable Cox regression models were built to ascertain the association with HF hospitalization. RESULTS: We included 762 patients with median age 60 (53-68) years, 68% (n=520) female, and median LDL-C level of 203 (194-216) mg/dL. Patients were followed for 4.7 (interquartile range 2.75-6.16) years, and 107 (14%) had a HF hospitalization. Overall, 355 (47%) patients had CAC=0, 210 (28%) had TAC=0, 116 (15%) had NAFLD, and median EAT was 79 mL (49-114). Moderate-Severe CAC (log-rank p<0.001) and TAC (log-rank p=0.006) groups were associated with increased HF hospitalizations. This association persisted when considering myocardial infarction (MI) as a competing risk. NAFLD and EAT volume were not associated with HF. CONCLUSIONS: In patients without established ASCVD and LDL-C≥190 mg/dL, CAC was independently associated with increased HF hospitalizations while TAC, NAFLD, and EAT were not.

HIV, HIV-specific Factors and Myocardial Disease in Women.

BACKGROUND: People with HIV (PWH) have an increased risk of cardiovascular disease (CVD). Cardiac magnetic resonance (CMR) has documented higher myocardial fibrosis, inflammation and steatosis in PWH, but studies have mostly relied on healthy volunteers as comparators and focused on men. METHODS: We investigated the associations of HIV and HIV-specific factors with CMR phenotypes in female participants enrolled in the Women's Interagency HIV Study's New York and San Francisco sites. Primary phenotypes included myocardial native (n) T1 (fibro-inflammation), extracellular volume fraction (ECV, fibrosis) and triglyceride content (steatosis). Associations were evaluated with multivariable linear regression, and results pooled or meta-analyzed across centers. RESULTS: Among 261 women with HIV (WWH, total n = 362), 76.2% had undetectable viremia at CMR. For the 82.8% receiving continuous antiretroviral therapy (ART) in the preceding 5 years, adherence was 51.7%, and 71.3% failed to achieve persistent viral suppression (42.2% with peak viral load < 200 cp/mL). Overall, WWH showed higher nT1 than women without HIV (WWOH) after full adjustment. This higher nT1 was more pronounced in those with antecedent or current viremia or nadir CD4+ count < 200 cells/µL, the latter also associated with higher ECV. WWH and current CD4+ count < 200 cells/µL had less cardiomyocyte steatosis. Cumulative exposure to specific ART showed no associations. CONCLUSIONS: Compared with sociodemographically similar WWOH, WWH on ART exhibit higher myocardial fibro-inflammation, which is more prominent with unsuppressed viremia or CD4+ lymphopenia. These findings support the importance of improved ART adherence strategies, along with better understanding of latent infection, to mitigate cardiac end-organ damage in this population.

Coronary Calcium Predicts All-Cause Mortality in Suspected Acute Aortic Syndrome.

Purpose: To determine long-term clinical outcomes in patients with suspected acute aortic syndrome (AAS) and evaluate the prognostic value of coronary calcium burden as assessed with CT aortography in this symptomatic population. Materials and Methods: A retrospective cohort of all patients who underwent emergency CT aortography from January 2007 through January 2012 for suspected AAS was assembled. A medical record survey tool was used to evaluate subsequent clinical events over 10 years of follow-up. Events included death, aortic dissection, myocardial infarction, cerebrovascular accident, and pulmonary embolism. Coronary calcium scores were computed from original images using a validated simple 12-point ordinal method and categorized into none, low (1-3), moderate (4-6), or high (7-12) groupings. Survival analysis with Kaplan-Meier curves and Cox proportional hazard modeling was performed. Results: The study cohort comprised 1658 patients (mean age, 60 years ± 16 [SD]; 944 women), with 595 (35.9%) developing a clinical event over a median follow-up of 6.9 years. Patients with high coronary calcium demonstrated the highest mortality rate (adjusted hazard ratio = 2.36; 95% CI: 1.65, 3.37). Patients with low coronary calcium demonstrated lower mortality, but rates were still almost twice as high compared with patients with no detectable calcium (adjusted hazard ratio = 1.89; 95% CI: 1.41, 2.53). Coronary calcium was a strong predictor of major adverse cardiovascular events (P < .001), which persisted after adjustment for common significant comorbidities. Conclusion: Patients with suspected AAS had a high rate of subsequent clinical events, including death. CT aortography-based coronary calcium scores strongly and independently predicted all-cause mortality.Keywords: Acute Aortic Syndrome, Coronary Artery Calcium, CT Aortography, Major Adverse Cardiovascular Events, Mortality Supplemental material is available for this article. © RSNA, 2023See also commentary by Weir-McCall and Shambrook in this issue.

Influence of BMI on virtual coronary artery calcium scoring.

PURPOSE: Virtual non-contrast (VNC) coronary artery calcium scoring (CAC) may obviate the need for traditional non-contrast (TNC) CAC. There is no data on the influence of body mass index (BMI) on VNC reliability. We aimed to evaluate the influence of BMI on VNC CAC agreement with TNC. MATERIALS AND METHODS: All patients who underwent sequential CAC and coronary CT angiography (CCTA) using spectral CT with TNC CAC > 0 between August 2020 and December 2021 were included. Agatston CAC scores were calculated manually by 2 blinded readers from VNC scans. A correction factor was calculated from the slope of the linear regression using the method of least squares and applied to the VNC scores. Bland-Altman plots and Cohen's weighted Kappa were utilized. RESULTS: We included 174 patients (57.5% female). Mean BMI was 32.6 ± 7.02 kg/m2 [BMI < 30 (39.7%); BMI 30-40 (45.4%); and BMI > 40 kg/m2 (14.9%)]. Mean TNC CAC was 177.8 ± 316.86 and mean VNC CAC after applying the correction factor 149.34 ± 296.73. The TNC value strongly correlated with VNC (r = 0.94; p < 0.0001). As BMI increased there was a progressive reduction in signal-to-noise ratio, contrast-to-noise ratio and coronary enhancement (p < 0.05). The degree of agreement between VNC and TNC CAC decreased as BMI increased (agreement = 91.79 (weighted Kappa = 0.72), 91.14 (weighted Kappa = 0.58) and 88.46% (weighted Kappa = 0.48) (all P values < 0.001) for BMI < 30; 30-40 and > 40 kg/m2, respectively). CONCLUSION: BMI has a significant influence on the accuracy of VNC CAC. VNC CAC shows substantial agreement in non-obese patients but performs poorly in BMI > 40 kg/m2. This is the first study to evaluate the influence of body mass index (BMI) on virtual non-contrast (VNC) coronary artery calcium scoring (CAC) as compared to traditional non-contrast (TNC). We retrospectively evaluated 174 patients with TNC CAC and two blinded reviewers manually calculated the VNC CAC. All cases were included without specific selection for quality. The ratio between the two directly proportional values was determined using the slope from the linear regression through the method of least squares. This correction factor of 2.65 was applied to the calcium scores obtained from VNC images. We found that VNC CAC shows substantial risk-class agreement with TNC in non-obese patients (agreement = 91.79 and weighted Kappa = 0.72) but performs poorly in BMI > 40 kg/m2 (agreement: 88.46% and weighted Kappa = 0.48). These findings show the potential use of VNC CAC to avoid additional radiation in non-obese patients. However, further research on potential improvement strategies for VNC CAC in obese patients is needed.

Deep learning of longitudinal chest X-ray and clinical variables predicts duration on ventilator and mortality in COVID-19 patients.

OBJECTIVES: To use deep learning of serial portable chest X-ray (pCXR) and clinical variables to predict mortality and duration on invasive mechanical ventilation (IMV) for Coronavirus disease 2019 (COVID-19) patients. METHODS: This is a retrospective study. Serial pCXR and serial clinical variables were analyzed for data from day 1, day 5, day 1-3, day 3-5, or day 1-5 on IMV (110 IMV survivors and 76 IMV non-survivors). The outcome variables were duration on IMV and mortality. With fivefold cross-validation, the performance of the proposed deep learning system was evaluated by receiver operating characteristic (ROC) analysis and correlation analysis. RESULTS: Predictive models using 5-consecutive-day data outperformed those using 3-consecutive-day and 1-day data. Prediction using data closer to the outcome was generally better (i.e., day 5 data performed better than day 1 data, and day 3-5 data performed better than day 1-3 data). Prediction performance was generally better for the combined pCXR and non-imaging clinical data than either alone. The combined pCXR and non-imaging data of 5 consecutive days predicted mortality with an accuracy of 85 ± 3.5% (95% confidence interval (CI)) and an area under the curve (AUC) of 0.87 ± 0.05 (95% CI) and predicted the duration needed to be on IMV to within 2.56 ± 0.21 (95% CI) days on the validation dataset. CONCLUSIONS: Deep learning of longitudinal pCXR and clinical data have the potential to accurately predict mortality and duration on IMV in COVID-19 patients. Longitudinal pCXR could have prognostic value if these findings can be validated in a large, multi-institutional cohort.

Prone Chest Radiographs: Distinguishing Features and Identification of Support Devices.

PURPOSE: Prone position is known to improve acute lung injury, and chest radiographs are often necessary to monitor disease and confirm support device placement. However, there is a paucity of literature regarding radiographs obtained in this position. We evaluated prone radiographs for distinguishing features and ability to identify support devices. METHODS: Pairs of prone and supine radiographs obtained during the COVID-19 pandemic were assessed retrospectively. IRB approval and waiver of informed consent were obtained. Radiographs were assessed for imaging adequacy, distinguishing features, and support device identification (endotracheal tube, enteric tube, or central line). Radiographs were reviewed by ≥ 2 cardiothoracic radiologists. RESULTS: Radiographs from 81 patients (63yo ± 13, 30% women) were reviewed. Prone and supine radiographs were comparable for imaging the lung bases (81% vs. 90%, p = 0.35) and apices (93% vs. 94%, p = 1); prone radiographs more frequently had significant rotation (36% vs. 19%, p = 0.021). To identify prone technique, scapula tip located beyond the rib border was 89% sensitive (95%CI 80-95%) and 85% specific (76-92%), and a fundal stomach bubble was 44% sensitive (33-56%) and 90% specific (81-96%). For women, displaced breast shadow was 46% sensitive (26-67%) and 92% specific (73-99%). Prone and supine radiographs each identified > 99% of support devices. Prone exams trended toward increased rate of malpositioned device (12% vs. 6%, p = 0.07). CONCLUSION: Scapula position reliably distinguishes prone from supine position; fundal stomach bubble or displaced breast shadow is specific for prone position. Prone radiographs reliably identify line and tube position, which is particularly important as prone patients appear at increased risk for malpositioned devices.

Visual Coronary and Aortic Calcium Scoring on Chest Computed Tomography Predict Mortality in Patients With Low-Density Lipoprotein-Cholesterol ≥190 mg/dL.

BACKGROUND: Current guidelines recommend coronary artery calcium (CAC) scoring for stratification of atherosclerotic cardiovascular disease risk only in patients with borderline to intermediate risk score by the pooled cohort equation with low-density lipoprotein-cholesterol (LDL-C) of 70 to 190 mg/dL. It remains unknown if CAC or thoracic aorta calcification (TAC), detected on routine chest computed tomography, can provide further risk stratification in patients with LDL-C≥190 mg/dL. METHODS: From a multisite medical center, we retrospectively identified all patients from March 2005 to June 2021 age ≥40 years, without established atherosclerotic cardiovascular disease and LDL-C≥190 mg/dL who had non-gated non-contrast chest computed tomography within 3 years of LDL-C measurement. Ordinal CAC and TAC scores were measured by visual inspection. Kaplan-Meier curves and multivariable Cox-regression models were built to ascertain the association of CAC and TAC scores with all-cause mortality. RESULTS: We included 811 patients with median age 59 (53-68) years, 262 (32.3%) were male, and LDL-C median level was 203 (194-217) mg/dL. Patients were followed for 6.2 (3.29-9.81) years, and 109 (13.4%) died. Overall, 376 (46.4%) of patients had CAC=0 and 226 (27.9%) had TAC=0. All-cause mortality increased with any CAC and moderate to severe TAC. In a multivariate model, patients with CAC had a significantly higher mortality compared with those without CAC: mild hazard ratio (HR), 1.71 (1.03-2.83), moderate HR, 2.12 (1.14-3.94), and severe HR, 3.49 (1.94-6.27). Patients with moderate TAC (HR, 2.34 [1.19-4.59]) and those with severe TAC (HR, 3.02 [1.36-6.74]) had higher mortality than those without TAC. CONCLUSIONS: In patients without history of atherosclerotic cardiovascular disease and LDL-C≥190 mg/dL, the presence and severity of CAC and TAC are independently associated with all-cause mortality.

Epidemiology, Risk Factors and Outcomes of Pneumomediastinum in Patients with Coronavirus Disease 2019: A Case-Control Study.

Background: Since the beginning of the ongoing Coronavirus Disease 2019 (COVID-19) pandemic, pneumomediastinum has been reported in patients with COVID-19 pneumonia and acute respiratory distress syndrome. It has been suggested that pneumomediastinum may portend a worse outcome in such patients although no investigation has established this association definitively. Research Question: We hypothesized that the finding of pneumomediastinum in the setting of COVID-19 disease may be associated with a worse clinical outcome. The purpose of this study was to determine if the presence of pneumomediastinum was predictive of increased mortality in patients with COVID-19. Study Design and Methods: A retrospective case-control study utilizing clinical data and imaging for COVID-19 patients seen at our institution from 3/7/2020 to 5/20/2020 was performed. 87 COVID-19 positive patients with pneumomediastinum were compared to 87 COVID-19 positive patients without pneumomediastinum and to a historical group of patients with pneumomediastinum during the same time frame in 2019. Results: The incidence of pneumomediastinum was increased more than 6-fold during the COVID-19 pandemic compared to 2019 (P = <.001). 1.5% of all COVID-19 patients and 11% of mechanically ventilated COVID-19 patients at our institution developed pneumomediastinum. Patients who developed pneumomediastinum had a significantly higher PEEP and lower P/F ratio than those who did not (P = .002 and .033, respectively). Pneumomediastinum was not found to be associated with increased mortality (P = .16, confidence interval [CI]: 0.89-2.09, 1.37). The presence of concurrent pneumothorax at the time of pneumomediastinum diagnosis was associated with increased mortality (P = .013 CI: 1.15-3.17, 1.91). Conclusion: Pneumomediastinum is not independently associated with a worse clinical prognosis in COVID-19 positive patients. The presence of concurrent pneumothorax was associated with increased mortality.

Incidence of new-onset atrial fibrillation in COVID-19 is associated with increased epicardial adipose tissue.

PURPOSE: Coronary artery calcium (CAC) and epicardial adipose tissue (EAT) can predict AF in the general population. We aimed to determine if CAC and EAT measured by computed tomographic (CT) scanning can predict new-onset AF in patients admitted with COVID-19 disease. METHODS: We performed a retrospective, post hoc analysis of all patients admitted to Montefiore Medical Center with a confirmed COVID-19 diagnosis from March 1st to June 23rd, 2020, who had a non-contrast CT of the chest within 5 years prior to admission. We determined ordinal CAC scores and quantified the EAT volume and examined their relationship with inpatient mortality. RESULTS: A total of 379 patients were analyzed. There were 16 events of new-onset AF (4.22%). Patients who developed AF during the index admission were more likely to be male (75 vs 47%, p < 0.001) and had higher EAT (129.5 [76.3-197.3] vs 91.0 [60.0-129.0] ml, p = 0.049). There were no differences on age (68 [56-71] vs 68 [58-76] years; p = 0.712), BMI (28.5 [25.3-30.8] vs 26.9 [23.1-31.8] kg/m2; p = 0.283), ordinal CAC score (3 [1-6] vs 2 [0-4]; p = 0.482), or prevalence of diabetes (56.3 vs 60.1%; p = 0.761), hypertension (75.0 vs 87.3%, p = 0.153), or coronary artery disease (50.0 vs 39.4%, p = 0.396). Patients with new-onset AF had worse clinical outcomes (death/intubation/vasopressors) (87.5 vs 44.1%; p = 0.001). CONCLUSION: Increased EAT measured by non-contrast chest CT identifies patients hospitalized with COVID-19 at higher risk of developing new-onset AF. Patients with new-onset AF have worse clinical outcomes.

Coronary artery calcification and epicardial adipose tissue as independent predictors of mortality in COVID-19.

Recent epidemiological studies have demonstrated that common cardiovascular risk factors are strongly associated with adverse outcomes in COVID-19. Coronary artery calcium (CAC) and epicardial fat (EAT) have shown to outperform traditional risk factors in predicting cardiovascular events in the general population. We aim to determine if CAC and EAT determined by Computed Tomographic (CT) scanning can predict all-cause mortality in patients admitted with COVID-19 disease. We performed a retrospective, post-hoc analysis of all patients admitted to Montefiore Medical Center with a confirmed COVID-19 diagnosis from March 1st, 2020 to May 2nd, 2020 who had a non-contrast CT of the chest within 5 years prior to admission. We determined ordinal CAC scores and quantified the epicardial (EAT) and thoracic (TAT) fat volume and examined their relationship with inpatient mortality. A total of 493 patients were analyzed. There were 197 deaths (39.95%). Patients who died during the index admission had higher age (72, [64-80] vs 68, [57-76]; p < 0.001), CAC score (3, [0-6] vs 1, [0-4]; p < 0.001) and EAT (107, [70-152] vs 94, [64-129]; p = 0.023). On a competing risk analysis regression model, CAC ≥ 4 and EAT ≥ median (98 ml) were independent predictors of mortality with increased mortality of 63% (p = 0.003) and 43% (p = 0.032), respectively. As a composite, the group with a combination of CAC ≥ 4 and EAT ≥ 98 ml had the highest mortality. CAC and EAT measured from chest CT are strong independent predictors of inpatient mortality from COVID-19 in this high-risk cohort.

A Retrospective Multi-Site Academic Center Analysis of Pneumothorax and Associated Risk Factors after CT-Guided Percutaneous Lung Biopsy.

PURPOSE: To assess the risk factors, incidence and significance of pneumothorax in patients undergoing CT-guided lung biopsy. METHODS: Patients who underwent a CT-guided lung biopsy between August 10, 2010 and September 19, 2016 were retrospectively identified. Imaging was assessed for immediate and delayed pneumothorax. Records were reviewed for presence of risk factors and the frequency of complications requiring chest tube placement. 604 patients were identified. Patients who underwent chest wall biopsy (39) or had incomplete data (9) were excluded. RESULTS: Of 556 patients (average age 66 years, 50.2% women) 26.3% (146/556) had an immediate pneumothorax and 2.7% (15/556) required chest tube placement. 297/410 patients without pneumothorax had a delayed chest X-ray. Pneumothorax developed in 1% (3/297); one patient required chest tube placement. Pneumothorax risk was associated with smaller lesion sizes (OR 0.998; 95% CI (0.997, 0.999); [p = 0.002]) and longer intrapulmonary needle traversal (OR 1.055; 95% CI (1.033, 1.077); [p < 0.001]). Previous ipsilateral lung surgery (OR 0.12; 95% CI (0.031, 0.468); [p = 0.002]) and longer needle traversal through subcutaneous tissue (OR 0.976; 95% CI (0.96, 0.992); [p = 0.0034]) were protective of pneumothorax. History of lung cancer, biopsy technique, and smoking history were not significantly associated with pneumothorax risk. CONCLUSION: Delayed pneumothorax after CT-guided lung biopsy is rare, developing in 1% of our cohort. Pneumothorax is associated with smaller lesion size and longer intrapulmonary needle traversal. Previous ipsilateral lung surgery and longer needle traversal through subcutaneous tissues are protective of pneumothorax. Stratifying patients based on pneumothorax risk may safely obviate standard post-biopsy delayed chest radiographs.

Thoracic aortic dissection classification among radiologists and surgeons and management trends.

OBJECTIVE: To investigate the discrepancy rate in classification of newly diagnosed aortic dissection (AD) between radiologists and surgeons and explore patient management. METHODS: 3255 CTs performed for AD from June 2013 to June 2018 at our institution were retrospectively identified. CT reports and charts were reviewed to identify newly diagnosed AD or intramural hematoma (IMH). Radiology reports and electronic health records were reviewed for Stanford type A or B classification and surgical versus medical management. RESULTS: Newly diagnosed AD was diagnosed in 1.9% (62/3255) with one false positive, mean age 60 years. Discrepancy rate was 1.6% (1/61). Type A AD/IMH was treated surgically in 85% (23/27), medically in 15% (4/27). Type B AD/IMH was treated surgically in 56% (19/34) (endovascular 95% (18/19)), medically in 44% (15/34). CONCLUSIONS: Discrepancy rate between radiologists and surgeons in Stanford classification of aortic dissection was low. Management of type B AD/IMH was predominantly endovascular, reflecting a shift in practice from the historical binary management strategy of type A dissections being treated surgically and type B dissections medically.

Meeting ACR Dose Guidelines for CT Lung Cancer Screening in an Overweight and Obese Population.

RATIONALE AND OBJECTIVES: Lung cancer screening adoption coincides with a growing obesity epidemic. Maintaining high-quality imaging at low radiation dose is challenging in obesity. We investigate the feasibility of meeting American College of Radiology (ACR) dose guidelines for lung cancer screening in a predominantly overweight and obese population. MATERIALS AND METHODS: Radiation dose (Volumetric CT dose index [CTDIvol], dose-length product), and body mass index (BMI) were collected for baseline screening CTs December, 2012-December, 2017. Dose metrics were analyzed according to BMI classification (normal <25, overweight 25-29, obese ≥30 kg/m2), using k = 0.014 mSv/mGy*cm. Results were compared to ACR dose guidelines and mean national 2017 Lung Cancer Screening Registry dose metrics. Analysis used Kruskal-Wallis (SPSS, version 24.0.0, IBM corp, Armonk, NY). RESULTS: Study population comprised 1478 patients (49.2% [727] women: mean BMI 28.1 ± 6.5 kg/m2, 26.9% [397] normal weight, 35.9% [530] overweight, 37.2% [551] obese). ACR dose requirements were met for both genders in all BMI classifications. Dose metrics were higher in men than in women; median effective dose and CTDIvol were 1.39 (0.8-1.58) mSv and 2.78 (1.41-2.80) mGy in men versus 1.16 (0.71-1.43) mSv and 2.70 (1.4-2.78) mGy in women. There were significant differences in dose metrics between men and women in the same BMI classification and between BMI classifications (p < 0.001). Mean dose metrics in our program were considerably lower than 2017 national average- mean CTDIvol and effective dose 2.45 ± 1.14 mGy and 1.26 ± 0.59 mSv versus 3.24 mGy and 1.35 mSv, respectively for our program and nationally. Mean dose metrics were also lower in our obese patients versus obese patients nationally. CONCLUSION: ACR dose metrics for lung cancer screening were met and can be appropriately tailored in a predominantly overweight and obese population clinical program.

Diagnostic Performance of Pulmonary Embolism Imaging in Patients with History of Asthma.

Asthma and pulmonary embolism (PE) can present with overlapping symptoms, and distinguishing between these 2 conditions can be challenging. Asthma may limit imaging for PE because of either worsened ventilation defects on ventilation-perfusion scanning (VQ) or increased motion artifacts on CT pulmonary angiography (CTPA). Methods: We identified adults evaluated for PE with VQ or CTPA from 2012 to 2016. Patients with chronic lung disease (other than asthma) were excluded. Studies were classified as negative, positive, or nondiagnostic. Follow-up of negative cases was reviewed to determine the rate of repeat exams (within 1 wk) and the false-negative rate (defined as diagnosis of venous thromboembolism within 90 d). Results: We reviewed 19,412 adults (aged 52 ± 18 y, 70% women) evaluated for PE (60% with VQ, 40% with CTPA); 23% had a history of asthma. Nondiagnostic results were comparable for those with and without asthma for both VQ (asthma, 3.3%; nonasthma, 3.8%; P = 0.223) and CTPA (asthma, 1.6%; nonasthma, 1.5%; P = 0.891). A history of asthma was not associated with a higher rate of repeat exams after negative imaging for VQ (asthma, 1.9%; nonasthma, 2.1%; P = 0.547) or CTPA (asthma, 0.6%; nonasthma, 0.6%; P = 0.796), nor was a history of asthma associated with a higher false-negative rate for VQ (asthma, 0.4%; nonasthma, 0.9%; P = 0.015) or CTPA (asthma, 1.9%; nonasthma 1.5%; P = 0.347). Conclusion: A history of asthma in the preceding 10 y was not associated with impaired diagnostic performance of PE imaging for either VQ or CTPA.

Echocardiography Abnormal Findings and Laboratory Operations during the COVID-19 Pandemic at a High Volume Center in New York City.

(1) Background: This study sought to explore how the novel coronavirus (COVID-19) pandemic affected the echocardiography (TTE) laboratory operations at a high volume medical center in New York City. Changes in cardiac imaging study volume, turn-around time, and abnormal findings were analyzed and compared to a pre-pandemic period. (2) Methods: Volume of all cardiac imaging studies and TTE reports between 11 March 2020 to 5 May 2020 and the same calendar period in 2019 were retrospectively identified and compared. (3) Results: During the pandemic, our center experienced a 46.72% reduction in TTEs, 82.47% reduction in transesophageal echocardiograms, 83.16% reduction in stress echo, 70.32% reduction in nuclear tests, 46.25% reduction in calcium score, 73.91% reduction in coronary computed tomography angiography, and 87.23% reduction in cardiac magnetic resonance imaging. TTE findings were overall similar between 2020 and 2019 (all p ≥ 0.05), except for a significantly higher right ventricular systolic pressure in 2020 (39.8 ± 14.2 vs. 34.6 ± 11.2 mmHg, p = 0.012). (4) Conclusions: Despite encountering an influx of critically ill patients, our hospital center experienced a reduction in the number of cardiac imaging studies, which likely represents a change in both patient mindset and physician management approach.

Implementation of an aortic dissection CT protocol with clinical decision support aimed at decreasing radiation exposure by reducing routine abdominopelvic imaging.

Patients suspected of having an acute aortic syndrome in the ED typically undergo CT of the chest/abdomen/pelvis. However, the overwhelming majority of these exams are negative. With the help of clinical decision support, we implemented a new radiologist monitored 'aortic dissection screening protocol' that forgoes routine abdominopelvic imaging in order to reduce radiation dose without compromising diagnostic accuracy. The purpose of the present study is to assess the performance of this protocol. A retrospective analysis was performed to study the effect of the dissection screening protocol on the diagnostic yield, radiation and contrast dose on a total of 835 ED patients who underwent CT scans for suspected aortic dissection over a 48-week study period immediately before and after implementation of the protocol. 3.4% (28/835) of examinations were positive for an acute aortic syndrome over the 48-week study period with no difference in positivity before and after implementation of the 'aortic dissection screening' protocol, 3.0% vs. 3.7%, respectively (p = 0.57). There was a 14.6% reduction in median radiation dose and a 16% decrease in contrast volume utilization for the total ED population who underwent CT for aortic dissection using any protocol in the period after implementation of the 'aortic dissection screening' protocol. Aortic dissection CT in the ED is negative in the overwhelming majority of cases. A monitored 'aortic dissection screening' protocol that initially images the chest only significantly reduced contrast and radiation dose without reducing diagnostic accuracy for ED patients who underwent CT for aortic dissection.