Subsegmental Pulmonary Arteries Research Articles

Detecting asymptomatic cement pulmonary embolisms following vertebral augmentation using dual-energy computed tomography pulmonary angiography.

Dual-energy computed tomography (DECT) pulmonary angiography can reliably detect cement pulmonary embolisms (CPEs) and parenchymal perfusion defects. This prospective observational study investigated CPEs in asymptomatic patients using DECT. We enrolled 42 patients who underwent vertebroplasty or received cement screws for vertebral augmentation, examining them using spinal computed tomography and DECT pulmonary angiography. An iodine map was employed to identify perfusion defects. We recorded the number, location, and perfusion defects of each CPE, and the vertebral cement distribution and perivertebral venous leakage patterns of prevertebral, paravertebral, epidural, and inferior vena cava leaks at each treated level. The presence of CPEs and perfusion defects was correlated with clinical factors and perivertebral venous leakage patterns in patient- and level-based analyses. Seven patients had 19 CPEs among them: fourteen in subsegmental arteries, two in segmental arteries, two in lobar arteries, and one in the main pulmonary artery. Twelve CPEs identified in four patients had corresponding perfusion defects on an iodine map. Patient-based univariable and multivariable logistic regression revealed that prevertebral leakage was significantly associated with the presence of CPEs (P<0.05). Prevertebral leakage was significantly associated in the univariable analysis with the presence of perfusion defects (P=0.025). In mixed-model univariable level-based logistic regression, prevertebral leakage was significantly associated with the presence of CPEs (P=0.04). CPEs frequently occur following vertebral augmentation, are associated with substantial prevertebral venous leakage, and predominantly occur in the subsegmental pulmonary artery. They do not always cause perfusion defects.

Improved detection of small pulmonary embolism on unenhanced computed tomography using an artificial intelligence-based algorithm - a single centre retrospective study.

To preliminarily verify the feasibility of a deep-learning (DL) artificial intelligence (AI) model to localize pulmonary embolism (PE) on unenhanced chest-CT by comparison with pulmonary artery (PA) CT angiography (CTA). In a monocentric study, we retrospectively reviewed 99 oncological patients (median age in years: 64 (range: 28-92 years); percentage of female: 39.4%) who received unenhanced and contrast-enhanced chest CT examinations in one session between January 2020 and October 2022 and who were diagnosed incidentally with PE. Findings in the unenhanced images were correlated with the contrast-enhanced images, which were considered the gold standard for central, segmental and subsegmental PE. The new algorithm was trained and tested based on the 99 unenhanced chest-CT image data sets. Based on them, candidate boxes, which were output by the model, were post-processed by evaluating whether the predicted box intersects with the patient's lung segmentation at any position. The AI-based algorithm proved to have an overall sensitivity of 54.5% for central, of 81.9% for segmental and 80.0% for subsegmental PE if taking n = 20 candidate boxes into account. Depending on the localization of the pulmonary embolism, the detection rate for only one box was: 18.1% central, 34.7% segmental and 0.0% subsegmental. The median volume of the clots differed significantly between the three subgroups and was 846.5 mm3 (IQR:591.1-964.8) in central, 201.3 mm3 (IQR:98.3-390.9) in segmental and 110.6 mm3 (IQR:94.3-128.0) in subsegmental PA (p < 0.05). The new algorithm proved to have high sensitivity in detecting PE in particular in segmental/subsegmental localization and may guide to decide whether a second contrast enhanced CT is necessary.

Application of a Deep Learning-Based Contrast-Boosting Algorithm to Low-Dose Computed Tomography Pulmonary Angiography With Reduced Iodine Load.

The aim of this study was to assess the effectiveness of a deep learning-based image contrast-boosting algorithm by enhancing the image quality of low-dose computed tomography pulmonary angiography at reduced iodine load. This study included 179 patients who underwent low-dose computed tomography pulmonary angiography with a reduced iodine load using 64 mL of a 1:1 mixture of contrast medium from January 1 to June 30, 2023. For single-energy computed tomography, the noise index was set at 15.4 to maintain a CTDIvol of <2 mGy at 80 kVp, and for dual-energy computed tomography, fast kV-switching between 80 and 140 kVp was employed with a fixed tube current of 145 mA. Images were reconstructed by 50% adaptive statistical iterative reconstruction (AR50) and a commercially available deep learning image reconstruction (TrueFidelity) package at a high strength level (TFH). In addition, AR50 images were further processed using a deep learning-based contrast-boosting algorithm (AR50-CB). Quantitative and qualitative image qualities and numbers of involved vessels with thrombus at each pulmonary artery level were compared in the 3 image types using the Friedman test and Wilcoxon signed rank test. Five hundred thirty-seven reconstructed image datasets of 179 patients were analyzed. Quantitative image analysis showed AR50-CB (30.8 ± 10.0 and 28.1 ± 9.6, respectively) had significantly higher signal-to-noise ratio and contrast-to-noise ratio values than AR50 (20.2 ± 6.2 and 17.8 ± 6.2, respectively) (P < 0.001) or TFH (28.3 ± 8.3 and 24.9 ± 8.1, respectively) (P < 0.001). Qualitative image analysis showed that contrast enhancement and noise scores of AR50-CB were significantly greater than those of AR50 (P < 0.001) and that AR50-CB enhancement scores were significantly higher than TFH enhancement scores (P < 0.001). The number of subsegmental pulmonary arteries affected by thrombus detected was significantly greater for AR50-CB (30 for AR50, 30 for TFH, and 55 for AR50-CB, P < 0.001). The use of a deep learning-based contrast-boosting algorithm improved image quality in terms of signal-to-noise ratio and contrast-to-noise ratio values and the detection of thrombi in subsegmental pulmonary arteries.

Clinical and radiological features associated with rupture of pulmonary artery pseudoaneurysm: a retrospective study

BackgroundHemoptysis resulting from rupture of the pulmonary artery pseudoaneurysm (PAP) is massive and fatal, while factor contributing to the rupture of pseudoaneurysm remains elusive. This study aimed to elucidate the clinical and radiological features of PAP and identify the risk factors associated with rupture.MethodsPatients who developed hemoptysis with PAP were collected from January 2019 to December 2022 retrospectively. Clinical data of the demographic characteristics, radiological findings, treatment strategies, and prognosis were collected. A comparative analysis was performed on the characteristics in the ruptured and non-ruptured cases.ResultsA total of 58 PAPs were identified in the 50 patients. The most common causes were infection (86%) and cancer (8%). The PAPs were located predominantly in the upper lobes of both lungs, and 57 (99.3%) were distributed in the segmental or subsegmental pulmonary arteries. The median diameter was 6.1(4.3–8.7) mm. A total of 29 PAPs were identified adjacent to pulmonary cavitations, with the median diameter of the cavity being 18.9 (12.4–34.8) mm. Rupture of pseudoaneurysm occurred in 21 cases (42%). Compared to unruptured group, the ruptured group had a significantly higher proportion of massive hemoptysis (57.1% vs. 6.9%, p < 0.001), larger pseudoaneurysm diameter (8.1 ± 3.2 mm vs. 6.0 ± 2.3 mm, p = 0.012), higher incidence of pulmonary cavitation (76.2% vs. 44.8%, p = 0.027), and larger cavitation diameters (32.9 ± 18.8 mm vs. 15.7 ± 8.4 mm, p = 0.005). The mean pulmonary artery pressure (mPAP) in the ruptured group was also significantly higher than that in the unruptured group [23.9 ± 7.4 mmHg vs. 19.2 ± 5.0 mmHg, p = 0.011]. Endovascular treatment was successfully performed in all 21 patients with ruptured PAP, of which the clinical success rate was 96.0%. Five patients experienced recurrent hemoptysis within one year.ConclusionsMassive hemoptysis, pseudoaneurysm diameter, pulmonary cavitation, and elevated mPAP were the risk factors for rupture of pseudoaneurysm. Our findings facilitate early identification and timely intervention of PAP at high risk of rupture.

Improved Pulmonary Artery Evaluation Using High-Pitch Photon-Counting CT Compared to High-Pitch Conventional or Routine-Pitch Conventional Dual-Energy CT.

Pulmonary CT angiography (CTA) to detect pulmonary emboli can be performed using conventional dual-source CT with single-energy acquisition at high-pitch (high-pitch conventional CT), which minimizes motion artifacts, or routine-pitch, dual-energy acquisitions (routine-pitch conventional DECT), which maximize iodine signal. We compared iodine signal, radiation dose, and motion artifacts of pulmonary CTA between these conventional CT modalities and dual-source photon-counting detector CT with high-pitch, multienergy acquisitions (high-pitch photon-counting CT). Consecutive clinically indicated pulmonary CTA exams were collected. CT number/noise was measured from the main to right lower lobe segmental pulmonary arteries using 120 kV threshold low, 120 kV, and mixed kV (0.6 linear blend) images. Three radiologists reviewed anonymized, randomized exams, rating them using a 4- or 5-point Likert scale (1 = worst, and 4/5 = best) for contrast enhancement in pulmonary arteries, motion artifacts in aortic root to subsegmental pulmonary arteries, lung image quality; pulmonary blood volume (PBV) map image quality (for multienergy or dual-energy exams), and contribution to reader confidence. One hundred fifty patients underwent high-pitch photon-counting CT (n = 50), high-pitch conventional CT (n = 50), and routine-pitch conventional DECT (n = 50). High-pitch photon-counting CT had lower radiation dose (CTDI vol : 8.1 ± 2.5 vs 9.6 ± 6.8 and 16.2 ± 8.5 mGy, respectively; P < 0.001), and routine-pitch conventional DECT had significantly less contrast ( P < 0.009). CT number and CNR measurements were significantly greater at high-pitch photon-counting CT ( P < 0.001). Across readers, high-pitch photon-counting CT demonstrated significantly higher subjective contrast enhancement in the pulmonary arteries compared to the other modalities (4.7 ± 0.6 vs 4.4 ± 0.7 vs 4.3 ± 0.7; P = 0.011) and lung image quality (3.4 ± 0.5 vs 3.1 ± 0.5 vs 3.1 ± 0.5; P = 0.013). High-pitch photon-counting CT and high-pitch conventional CT had fewer motion artifacts at all levels compared to DECT ( P < 0.001). High-pitch photon-counting CT PBV maps had superior image quality ( P < 0.001) and contribution to reader confidence ( P < 0.001) compared to routine-pitch conventional DECT. High-pitch photon-counting pulmonary CTA demonstrated higher contrast in pulmonary arteries at lower radiation doses with improved lung image quality and fewer motion artifacts compared to high-pitch conventional CT and routine-pitch conventional dual-energy CT.

Optimisation of virtual monoenergetic reconstructions for the diagnosis of pulmonary embolism using photon-counting detector computed tomography angiography

PurposeComputed tomography (CT) pulmonary angiography is considered the gold standard for pulmonary embolism (PE) diagnosis, relying on the discrimination between contrast and embolus. Photon-counting detector CT (PCD-CT) generates monoenergetic reconstructions through energy-resolved detection. Virtual monoenergetic images (VMI) at low keV can be used to improve pulmonary artery opacification. While studies have assessed VMI for PE diagnosis on dual-energy CT (DECT), there is a lack of literature on optimal settings for PCD-CT-PE reconstructions, warranting further investigation.Material and methodsTwenty-five sequential patients who underwent PCD-CT pulmonary angiography for suspicion of acute PE were retrospectively included in this study. Quantitative metrics including signal-to-noise ratio (SNR) and contrast-to-noise (CNR) ratio were calculated for 4 VMI values (40, 60, 80, and 100 keV). Qualitative measures of diagnostic quality were obtained for proximal to distal pulmonary artery branches by 2 cardiothoracic radiologists using a 5-point modified Likert scale.ResultsSNR and CNR were highest for the 40 keV VMI (49.3 ± 22.2 and 48.2 ± 22.1, respectively) and were inversely related to monoenergetic keV. Qualitatively, 40 and 60 keV both exhibited excellent diagnostic quality (mean main pulmonary artery: 5.0 ± 0 and 5.0 ± 0; subsegmental pulmonary arteries 4.9 ± 0.1 and 4.9 ± 0.1, respectively) while distal segments at high (80-100) keVs had worse quality.Conclusions40 keV was the best individual VMI for the detection of pulmonary embolism by quantitative metrics. Qualitatively, 40-60 keV reconstructions may be used without a significant decrease in subjective quality. VMIs at higher keV lead to reduced opacification of the distal pulmonary arteries, resulting in decreased image quality.

Abstract 17842: 3D Visualization and Quantitative Assessment of the Pulmonary Arteries on CT Using Deep Learning Segmentation

Introduction: Assessment of the pulmonary arteries (PA) on CT scan is typically qualitative and requires review of hundreds of images. PA segmentation would enable creation of 3D reconstructions that visualize the entire pulmonary arterial tree in a single image, similar to catheter angiography, and also enable quantification of pathophysiologic changes. Manual segmentation is very time-consuming, but deep-learning (DL) can automate the process. Hypothesis: A DL segmentation algorithm can be used to automatically generate 3D reconstructions of the PAs and quantify morphologic changes seen in Chronic Thromboembolic Pulmonary Hypertension (CTEPH) and Pulmonary Arterial Hypertension (PAH). Methods: A DL algorithm based on a 3D U-Net architecture which segments PAs larger than 2 mm was trained and validated on a total of 250 contrast-enhanced CT chest. The study group included 15 CTEPH and 15 PAH patients seen consecutively in pulmonary hypertension (PH) clinic in 2022 with prior CT chest and right heart catheterization, and 10 additional patients with prior CT chest and no evidence of PH on same day echo (normal). After running the DL algorithm on CTs, 3D renderings were created from segmentations and the relative volume of the central, interlobar, and segmental/subsegmental PAs was derived. Results: 3D renderings of PAH and CTEPH patients showed larger central and interlobar PAs compared with those of normal patients, whereas segmental and subsegmental PAs were smaller and pruned in CTEPH patients (Figure). Quantitatively, the volume of the central and interlobar PAs was higher in CTEPH and PAH compared to normal (p &lt; 0.05). The combined volume of segmental/subsegmental PAs was smaller in CTEPH patients relative to normal and PAH patients (p &lt; 0.005). Conclusions: DL segmentation enables intuitive visualization and quantification of the morphologic changes to the PAs seen in conditions causing PH. This method may improve diagnosis and assessment of PH on CT.

Incidental central pulmonary emboli in outpatients with deep vein thrombosis.

While it has been demonstrated that large asymptomatic pulmonary embolism (PE) can occur, many studies have assessed inpatients or patients with known risk factors for venous thromboembolism (such as malignancy). There are few data regarding incidental PE in outpatients with deep vein thrombosis (DVT) or assessing whether these emboli occur centrally or peripherally in the pulmonary arteries. To determine the rates of incidental central and peripheral PE in outpatients with proximal and distal DVT. This was a retrospective cross-sectional study of 120 patients attending our community imaging clinic between January 2015 and March 2020, with ultrasound-confirmed lower limb DVT, and subsequent computed tomography pulmonary angiogram (CTPA) within 24 h. Exclusion criteria were symptoms indicative of PE. Imaging reports were retrospectively reviewed to record the proximity of DVT and the location of any PE as either central (pulmonary trunk or main pulmonary arteries) or peripheral (lobar, segmental or subsegmental pulmonary arteries). Incidental PE occurred in 71 patients (59.2%), with a rate of 77.5% in proximal and 50.0% in distal DVT. Sixteen patients had central PE (13.3% of all patients with DVT; 22.5% of all patients with PE). Two patients (both with proximal DVT) had PE in the pulmonary trunk. Incidental PE occur frequently in outpatients with lower limb DVT, including the possibility of asymptomatic central emboli. Further studies with larger patient cohorts would be useful to assess the utility of baseline chest imaging in outpatients with DVT.

An atlas of anatomical variants of subsegmental pulmonary arteries and recognition error analysis.

Surgery, including lobectomy and segmentectomy, is the major curative intervention for lung cancer. Surgical planning for pulmonary surgery is difficult due to the high variation rate of pulmonary arteries and needs a fine-grained atlas as a reference. We conducted a study to create a surgically oriented atlas and analyzed the error encountered during the production. A total of 100 Chest CTs performed at Peking University People's Hospital from 2013.09 to 2020.10 were randomly selected for segmental artery labeling. Dicom files were collected for 3D reconstruction. Manual segmentation of each segmental artery was performed by 4 thoracic surgeons. Cross-validation by surgeons was performed to establish the golden standard based on their consensus. Initial recognition errors were recorded accordingly. The most frequently seen variants for the right upper lobe is 2-branch RA1+2rec+3 and RA2asc; right middle lobe 2-branch RA4a and RA4b+5; right lower lobe 3-branch RA7, RA8 and RA9+10; left upper lobe 3-branch LA1+2a+3, LA1+2b, LA1+2c and 1-branch LA4+5; left lower lobe 2-branch LA8 and LA9+10. Top 5 segmental error occurs in RA4 (23%), LA8 (17%), RA9 (17%), RA8 (14%) and LA9 (11%). A rapid surgical planning tool form was created based on high frequency anatomic variants. Our research provided an atlas for lobectomy and segmentectomy at the subsegmental or more distal level. We demonstrated that the recognition accuracy of pulmonary arteries in a non-time-sensitive experimental scenario was still unfavorable. We also suggest that extra attention should be paid to certain surgeries during the surgical planning process.

The First Reported Case of Pulmonary Embolism and Deep Vein Thrombosis Associated with Intraductal Papillary Mucinous Neoplasm: A Case Report

Background: Reported cases of Intraductal papillary mucinous neoplasm (IPMN) are becoming more and more frequent. The risk of hypercoagulability associated with IPMN is not clearly established in the literature as it was only reported in four cases. Therefore, we present a unique case of a patient with IPMN who subsequently developed acute pulmonary embolism (PE) and deep venous thrombosis (DVT). Case presentation: A 70-year-old healthy female patient complained of palpitation, chest pain, and dyspnea at rest. She had normal vital signs and findings on physical examination. Laboratory tests showed an increase in the D-Dimer level of 3,730 ng/mL fibrinogen equivalent unit (FEU). Bilateral DVT ultrasound (DVT-US) of the lower extremities was positive for acute calf DVT in the right lower extremity involving the soleal vein. CT-PE chest with IV contrast was remarkable for segmental and subsegmental pulmonary arteries thrombosis. She was started on a heparin drip and then transitioned to rivaroxaban for the treatment of PE and DVT. She was discharged in stable condition with outpatient follow-up. Conclusion: IPMN of the pancreas is an exocrine pancreatic neoplasm often detected on Computed Tomography (CT) scan or Magnetic Resonance Imaging (MRI). It is usually non-malignant but was found to be more prone to progress into cancer in contrast to the other types of pancreatic cysts. An increased risk of hypercoagulability with pre-malignant pancreatic lesions such as IPMN has not yet been well established. As far as we know, this case report is the first article presenting IPMN associated with both acute DVT and PE in a relatively healthy individual with no prior risk factor for hypercoagulability. Although there is scattered evidence suggesting an increased risk of thromboembolic events with IPMN, this unique case of DVT and PE associated with IPMN highlights the importance of close monitoring of these patients, especially those who have risk factors for thrombosis.

Massive Left Ventricular Thrombus in the Setting of COVID-19–Induced Systemic Thrombi

A 58-year-old White man with no known medical history initially presented to the emergency department for fatigue and was ultimately diagnosed with COVID-19. He was in stable condition and discharged to quarantine at home. He returned to the emergency department 2 weeks later with a chief report of progressive pain and swelling of his legs. Initial vitals were remarkable for a heart rate of 115/minute. Physical examination revealed edematous and erythematous lower extremities with weeping wounds. Laboratory workup was remarkable for a white blood cell count of 12.7 × 1,000/μL, platelet count of 81 × 1,000/μL, troponin I level of 0.678 ng/mL, brain natriuretic peptide level of 4,000 pg/mL, C-reactive protein level of 121 mg/L, lactate level of 3.7 mmol/L, and international normalized ratio of 1.5.Chest computed tomographic angiography revealed acute emboli of subsegmental pulmonary arteries of the left upper, middle, and lower lobes (Fig. 1). Echocardiogram revealed a severely dilated left ventricle with apical akinesis and an ejection fraction of 10% to 15%. Large, layered thrombi were seen in the apex of the left and right ventricles (Fig. 2). Duplexes of the lower extremities showed acute occlusive calf vein thrombi in the right posterior tibial and bilateral peroneal veins. Arteries were patent in both lower extremities. Venous duplex of the right upper extremity revealed acute superficial venous thrombi in the right basilic and cephalic veins. Cardiac magnetic resonance imaging was performed to assess viability, which revealed significant transmural scarring and a large thrombus (8 × 6 × 5 cm) occupying the mid- and complete apical left ventricle cavity (Fig. 3). Multiple small thrombi in the right ventricle apex were seen.Given the thrombocytopenia on presentation, there was concern for disseminated intravascular coagulation; however, with such extensive clot burden, the patient was started on a heparin drip. Four days later, he sustained a cardiac arrest secondary to venous thromboembolism. Upon achieving return of spontaneous circulation, he was taken for left heart catheterization, which revealed severe triple-vessel disease. Cardiothoracic surgery was consulted, but it was determined that the patient to be too high risk to undergo coronary artery bypass graft or operative thrombectomy. Ultimately, his clinical status deteriorated, and the patient along with family proceeded with comfort measures.SARS-CoV-2 infection primarily affects the lower respiratory tract, but there are reports of COVID-19–induced cardiac complications, including acute coronary syndromes, arrythmias, myocarditis, and thrombosis.1 Venous thromboembolism is reported to occur in approximately 30% of patients with COVID-19, but intracardiac thrombus in very rare.2 Cardiac thrombus should be considered in the diagnosis of COVID-19 in patients presenting with chest pain and leg swelling.

Association of Clinical and Laboratory Findings in COVID-19 Patients with Thromboembolic Complications

Background: COVID-19 is associated with dangerous thromboembolic complications, such as stroke, heart attack, pulmonary embolism, and arterial and venous thromboembolism (VTE). Early diagnosis and even prediction of thromboembolic complications using biomarkers could facilitate the treatment and decrease the mortality rate. Objectives: This study evaluated and compared the clinical and laboratory findings of COVID-19 patients with thrombotic events with other COVID-19 patients. Methods: A total of 114 confirmed COVID-19 patients referred to Taleghani Hospital, Tehran, Iran, between February and September 2020 were included in this cross-sectional study. Those with a history of thromboembolic disease were excluded. The laboratory data, including the levels of lactate dehydrogenase (LDH), D-dimer, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and counts of lymphocyte and neutrophil, along with clinical findings (such as oxygen saturation and lung involvement percentage), were retrospectively collected from the patients’ clinical files. The incidence of thrombotic events was evaluated in patients. Results: The prevalence of thrombosis in the right and left main pulmonary arteries, right and left sub-segmental pulmonary arteries, and right and left deep veins was 2.7%, 3.5%, 7%, 7.9%, 4.4%, and 1.8% of all patients, respectively. The results showed that thromboembolic complications were significantly associated with mortality (P &lt; 0.001). Besides, it was found that LDH (P &lt; 0.001) and neutrophil (P = 0.002) levels in thromboembolic COVID-19 patients were respectively higher and lower than those without thromboembolic manifestations. Conclusions: High LDH and neutropenia might serve as biomarkers for thromboembolism in COVID-19 patients.

Pulmonary Vascular Remodeling and Prognosis in Patients Evaluated for Heart Transplantation: Insights from the OCTOPUS-CHF Study.

In patients with advanced heart failure, the intravascular optical coherence tomography (OCT) of subsegmental pulmonary artery measurements is correlated with right heart catheterization parameters. Our aim was to study the prognostic value of pulmonary OCT, right heart catheterization data, and the echocardiographic estimation of pulmonary pressure in patients studied for elective heart transplants. This research is an observational, prospective, multicenter study involving 90 adults with a one-year follow-up. A total of 10 patients (11.1%) died due to worsening heart failure before heart transplantation, 50 underwent a heart transplant (55.6%), and 9 died in the first year after the transplant. The patients with and without events (mortality or heart failure-induced hospitalization) had similar data regarding echocardiography, right heart catheterization, and pulmonary OCT (with a median estimated pulmonary artery systolic pressure of 42.0 mmHg, interquartile range (IQR) of 30.3-50.0 vs. 47.0 mmHg, IQR 34.6-59.5 and p = 0.79, median pulmonary vascular resistance of 2.2 Wood units, IQR 1.3-3.7 vs. 2.0 Wood units, IQR 1.4-3.2 and p = 0.99, and a median pulmonary artery wall thickness of 0.2 ± 0.5 mm vs. 0.2 ± 0.6 mm and p = 0.87). Pulmonary vascular remodeling (evaluated with echocardiography, right heart catheterization, and pulmonary OCT) was not associated with prognosis in a selected sample of adults evaluated for elective heart transplants. Pulmonary OCT is safe and feasible for the evaluation of these patients.

Using barium as an internal radioprotective shield for pregnant patients undergoing CT pulmonary angiography: A retrospective study

PurposeThe purpose of our retrospective study was to assess the effect of barium sulfate contrast medium on radiation dose and diagnostic quality of CT Pulmonary Angiography (CTPA) in an in-vivo study of pregnant patients. MethodsOur retrospective study included 33 pregnant patients who underwent CTPA to exclude pulmonary embolism. The patients received oral 40% w/v barium solution just prior to the acquisition of their planning radiograph. All CTPA were performed on 64-slice, single-source CT scanners with AEC with noise index = 28.62–31.64 and the allowed mA range of 100–450. However, only 5/33 patients had mA modulation (AEC 100–450 mA range), while 28/33 patients had mA maxed out at the set maximum mA of 450 over the entire scan range. We recorded CTDIvol (mGy), DLP (mGy.cm) and scan length. The same information was recorded in weight-and scanner-matched, non-pregnant patients. Statistical tests included descriptive data (median and interquartile range) and Mann-Whitney test. ResultsThere were no significant differences in CTDIvol and DLP between the barium and control group patients (p > 0.1). The median mA below the diaphragm was significantly higher in each patient with barium compared to the weight and scanner-matched patient without barium. Evaluation of lung and subsegmental lower lobe pulmonary arteries was limited in 85% barium group. Due to thin prospective section thickness (1.25 mm), most patients were scanned at maximum allowed mA for AEC. ConclusionUse of AEC with thick barium in pregnant patients undergoing CTPA as an internal radioprotective shield produces counterproductive artifacts and tube current increments.

Zatorowość płucna u młodej kobiety z zakrzepicą żył głębokich po doustnych lekach antykoncepcyjnych

Twenty years old woman was admitted to a local hospital with pain, redness, swelling of the left extremity, general malaise, and fatigue. Performed duplex ultrasound revealed massive thrombus originating in anterior tibial, posterior tibial, and fibular veins, continuing through popliteal and femoral till the external iliac vein. Two months earlier, the patient was ordered oral contraceptive therapy. The treatment regime which was scheduled included low-molecular-weight heparin. Because there was no clinical improvement 12 days later, there was performed computed tomography pulmonary angiography. This diagnostic examination showed that deep vein thrombosis was complicated by pulmonary embolism — there were thrombi in subsegmental pulmonary arteries of the bottom lobes of both lungs. The pulmonary embolism was low-risk because there was no observed hypotony and any signs of myocardial injury — cardiac troponins and B-type natriuretic peptide levels remained within the normal range values. Because there was no improvement a few days later, the patient was referred to a higher reference university hospital with Cardiac Intensive Care Unit. In this stage, subcutaneous low-molecular-weight heparin was replaced by an intravenous infusion of unfractionated heparin. After a few days of treatment, symptoms started to deteriorate.

Challenges in Managing Isolated Subsegmental Pulmonary Embolism.

This commentary explores the clinical conundrums arising when caring for patients with acute pulmonary embolism isolated to the subsegmental pulmonary arteries. We discuss ways to confirm the radiologic diagnosis, how to distinguish patients for whom anticoagulation is indicated from those who are eligible for structured surveillance without anticoagulation, what surveillance entails, and why ensuring continuity of care matters. We report a case from our own experience that illustrates these decision-making crossroads and highlights the importance of cross-disciplinary collaboration. Because the evidence in the literature is currently weak and indirect, we draw on expert opinion in US and European guidelines, a recent statement from a multidisciplinary consensus panel, and several ongoing well-designed clinical trials. This discussion will help clinicians better manage the spectrum of patients who present with isolated subsegmental embolism.

Thromboembolic Risk in COVID-19 Patients: Is There a Hidden Link?

BackgroundAlthough evidence has emerged indicating that patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia present a high risk of venous thromboembolism (VTE), its real incidence and best diagnosis course remain unclear. In this study, we aimed to determine the incidence of pulmonary embolism in these patients and the role of D-dimer serum level as a predictive factor of a new VTE event.MethodologyThis was a single-center retrospective observational cohort study conducted in a tertiary hospital. All patients admitted to the infectious diseases ward with SARS-CoV-2 pneumonia with clinical or laboratory criteria for suspected VTE events were eligible for inclusion in the study. The t-test or Mann-Whitney U test was used to analyze the differences between the with-VTE group and the without-VTE group.ResultsOverall, VTE incidence was registered to be 30%. Chest computed tomography angiography data revealed thrombus mainly in segmental (five patients, 71%) and subsegmental pulmonary artery branches (four patients, 57%). No thrombus on major branches was documented. D-dimer serum levels (collected at hospital admission, 48 hours before the suspected VTE event date and at suspected VTE event date) were analyzed, and, despite a consistent tendency of higher values in the with-VTE group, no statistical difference was observed. Moreover, no statistical difference was observed between the two groups in mortality rates.ConclusionsA clear higher risk of VTE events in SARS-CoV-2 pneumonia patients was not documented, and a link between the impact of VTE occurrence and a worse prognosis was not demonstrated. Therefore, we suggest that the use of D-dimer serum level should not be used as a predictor of VTE in SARS-CoV-2 pneumonia patients.

Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension: advances in patient and lesion selection.

Balloon pulmonary angioplasty (BPA) has been performed worldwide for patients who are ineligible for pulmonary endarterectomy (PEA). However, the technical details of BPA have not been standardized, and no international consensus regarding patient and lesion selection for BPA has been reached. Evidence for the combination of BPA with PEA or medical therapy is also lacking. This review highlights recent progress in BPA in terms of patient and lesion selection and the current procedural approach for BPA, including combination treatment. The indications for BPA have expanded with recent reports describing the improved safety and efficacy of BPA. Because lesions are generally present in all segmental and subsegmental pulmonary arteries, it is recommended to treat all the lesions to achieve desirable hemodynamic improvement. Selective pulmonary angiography is the gold standard for lesion selection in modern BPA aimed at total revascularization. Despite the lack of randomized controlled studies, combination treatment with BPA may be well tolerated and effective. BPA, alone or in combination with PEA or medical therapy, may be a treatment option for patients who are not candidates for monotreatment of PEA. However, further investigation is required to standardize patient and lesion selection for BPA.

Pulmonary Embolism in a Patient with Well’s Score of Zero

Pulmonary embolism is a condition in which a blood clot blocks a vessel in the lungs. It is a venous thromboembolism that is common and sometimes may prove to be life threatening. Well’s score/Well’s criteria calculates the risks of developing deep vein thrombosis and subsequently pulmonary embolism. Well’s score is based on clinical symptoms of DVT (leg swelling, pain with palpation)(3.0 points each), other diagnosis less likely than pulmonary embolism (3.0 points each), heart rate more than 100 (1.5 points each), immobilization or surgery in the last four weeks (1.5 points each), previous DVT/PE (1.5 points each), hemoptysis (1.0 points), malignancy (1.0 points). If the patient scores 3 or higher there is a high risk of DVT. 1 or 2 score is a moderate risk of DVT. In patients with moderate or higher probability for DVT (cut-off scores of 2), the Well’s score was able to detect patients at risk of developing DVT with a sensitivity of 67% and specificity of 90%. We hereby present a 40-year-old lady with no significant past medical history, who presented to the emergency department with sudden onset of non-radiating right sided chest pain and shortness of breath worsened with walking. Patient denied smoking, recent travels, OCP, recent surgeries, immobilization, previous DVT, pulmonary embolism, hemoptysis, malignancy, miscarriages, lupus. No family history of coagulopathies. Vitals were stable with Blood pressure of 101/60 mmHg, heart rate of 77 beats/minute, afebrile, Respiratory rate of 18, saturating 99% on room air. On examination no leg swelling or tenderness noted, no Intercostal Retraction, no use of accessory muscles, lungs clear to auscultation bilaterally. Venous Doppler study was unremarkable. Chest x ray did not show any cardio-pulmonary disease. The Well’s score came out to be zero with pulmonary embolism very low in the differential. We decided to do CT chest which showed small pulmonary emboli involving bilateral lower lobe sub-segmental pulmonary arteries. D-dimer came out to be 1938. All the rest of the labs and the coagulation factors were within normal limits. We started the patient on lovenox subQ 60 mg Q12 hourly with improvement in the shortness of breath. Patient was discharged on Xarelto. The possibility of DVT should still be considered if the patient presents with shortness of breath with zero Well’s Score.

18F-fluorodeoxyglucose PET/CT findings in a systemic inflammatory response syndrome after COVID-19 vaccine

A 65-year-old woman attended our hospital with a 1-day history of fever and falls, saying that her legs had given out from under her. The patient's symptoms began within 1 day of the first dose of the mRNA-1273 SARS-CoV-2 vaccine. She had a medical history of hypertension and diabetes. On examination in the emergency department, the patient's temperature was 39·1°C, her respiratory rate was 25 breaths per min, and her heart rate was 88 beats per min. As she met the criteria for systemic inflammatory response syndrome (SIRS), an extensive infection work-up was initiated and she was started on broad-spectrum antibiotics. Laboratory investigations found a D-dimer concentration of 5267 ng/mL, erythrocyte sedimentation rate of 69 mm/h, and a C-reactive protein concentration of 63·4 mg/L. The patient's white blood cell count, lactate, urinalysis, respiratory pathogen panel—including SARS-CoV-2—and urine and blood cultures were unremarkable. Due to concerns of exposure to SARS-CoV-2, the PCR test was repeated after 24 h, but this was again negative. CT of the patient's chest showed multiple pulmonary nodules measuring up to 1·1 cm. A small filling defect in a distal subsegmental pulmonary artery was also seen, which we thought was inconsistent with an acute pulmonary embolism and probably artifactual. Doppler ultrasounds of the patient's lower limbs were normal; her head CT was also normal. 4 days after presentation, 18F-fluorodeoxyglucose (18F-FDG) PET/CT was done to characterise the pulmonary nodules; it showed uptake in the fat stranding posterior to the right deltoid (figure); moderately increased uptake within multiple right axillary lymph nodes (figure); and diffusely increased splenic uptake (figure). The pulmonary nodules had no uptake—indicating that they were probably benign. The patient's symptoms resolved 3 days after the vaccination. Given the imaging findings, the temporal relationship of the symptoms to the vaccination, and negative test results from an extensive work-up for malignant and infectious causes, we believe, the diagnosis was a local and systemic immune response following vaccination. However possible masking effects of broad-spectrum antibiotics cannot be excluded. The high D-dimer concentration probably reflected significant concomitant coagulation and fibrinolysis associated with SIRS. The local response was demonstrated by hypermetabolism within the axillary lymph nodes draining the site of intramuscular injection; diffusely increased splenic activity suggests a systemic response—corroborated by elevated inflammatory markers. As the global vaccination effort continues, more patients will undoubtedly require assessment and investigation shortly after immunisation. Imaging and laboratory findings consistent with a systemic immune response might result in further unnecessary evaluation or interventions. However, findings overlap with other diseases—notably those of the 18F-FDG PET/CT scan in patients with malignancies. Recognition of the clinical and imaging features of the systemic immune response to vaccination might become essential in the coming months (video). Contributors AT was the admitting physician treating the patient. JS and AI were involved in interpreting the imaging. We were all involved in drafting, reviewing, and writing the final manuscript. Written consent for publication was obtained from the patient. Declaration of interests We declare no competing interests. eyJraWQiOiI4ZjUxYWNhY2IzYjhiNjNlNzFlYmIzYWFmYTU5NmZmYyIsImFsZyI6IlJTMjU2In0.eyJzdWIiOiIzYjU0YjdkMGRlOWE5YjRjZjE3NTczNTFlMGYwYTE5MiIsImtpZCI6IjhmNTFhY2FjYjNiOGI2M2U3MWViYjNhYWZhNTk2ZmZjIiwiZXhwIjoxNjc1MDIwNzk3fQ.FrKm7WPVrBEYc__av88QAKtYcG-LEqw9a4HNT5cWjqdAQd-pxui5ft-V7JsWf9GshC_PMhztK_Dm82QamMvpkGf3XrdBQnfZKg9ybgvg8lU8czKB09lBfyyTnOHwfilUJXrDCmhjFGrkbSyeQE5VXa5JY5y8txPhDfsEX5jlz2K7YL5WkY0Kl1lcQnqyRwQDqh416BrsCgYyy1SgRJcISHSsbjihKsGSKXjvGh_FVevzPS7J3WLK--W7BbBgefHaOMk8j6ua_FwQO4TXBX4bmVWopN1RRZ1ZRGkjOzH9vsJxXisqWxGtGBnkMQmCoC7hm3o9Je2pyGOrpNnCT6H8og Download .mp4 (35.03 MB) Help with .mp4 files Supplementary Video18fluorodeoxyglucose PET/CT shows possible response to COVID-19 vaccineLymph nodes and spleen lighting up after COVID-19 vaccineYoutube: https://youtu.be/Cjf4zUr6mXo