The aims of this study were to determine the functional biocompatibility of low-concentration SDS-decellularized porcine aortic roots in vivo. A previously developed process was modified for 9- and ...15-mm-diameter aortic roots to facilitate implantation into the porcine abdominal aorta (n=3) and juvenile sheep right ventricular outflow tract (n=7), respectively. Native allogeneic aortic roots were used as controls. Acellular porcine roots explanted from pigs at weeks were largely repopulated with stromal cells of appropriate phenotype, and there was evidence that macrophages were involved in the regenerative process. Native allogeneic roots were subject to a classic allograft rejection response. Acellular porcine roots explanted from sheep at 6 months showed evidence of appropriate cellular repopulation, again with evidence of a role for macrophages in the regenerative process. There was some degree of calcification of two of the explanted acellular roots, likely due to incomplete removal of DNA before implantation. Native allogeneic ovine roots were subject to a classic allograft rejection response involving T cells, which resulted in overtly calcified and damaged tissues. The study highlighted (1) the importance of removal of DNA from acellular porcine valved roots to avoid calcification and (2) a role for macrophages in the regeneration of low-concentration SDS-decellularized aortic roots, as has been reported for other acellular biological extracellular matrix scaffolds.
The aim of the study was to derive and compare metabolic parameters relating to benign and malignant pulmonary nodules using dynamic 2-deoxy-2-fluorine-18fluoro-D-glucose (18F-FDG) PET/CT, and nodule ...perfusion parameters derived through perfusion computed tomography (CT).Twenty patients with 21 pulmonary nodules incidentally detected on CT underwent a dynamic 18F-FDG PET/CT and a perfusion CT. The maximum standardized uptake value (SUVmax) was measured on conventional 18F-FDG PET/CT images. The influx constant (Ki) was calculated from the dynamic 18F-FDG PET/CT data using Patlak model. Arterial flow (AF) using the maximum slope model and blood volume (BV) using the Patlak plot method for each nodule were calculated from the perfusion CT data. All nodules were characterized as malignant or benign based on histopathology or 2 year follow up CT. All parameters were statistically compared between the two groups using the nonparametric Mann-Whitney test.Twelve malignant and 9 benign lung nodules were analysed (median size 20.1 mm, 9–29 mm) in 21 patients (male/female = 11/9; mean age ± SD: 65.3 ± 7.4; age range: 50–76 years). The average SUVmax values ± SD of the benign and malignant nodules were 2.2 ± 1.7 vs. 7.0 ± 4.5, respectively (p = 0.0148). Average Ki values in benign and malignant nodules were 0.0057 ± 0.0071 and 0.0230 ± 0.0155 min-1, respectively (p = 0.0311). Average BV for the benign and malignant nodules were 11.6857 ± 6.7347 and 28.3400 ± 15.9672 ml/100 ml, respectively (p = 0.0250). Average AF for the benign and malignant nodules were 74.4571 ± 89.0321 and 89.200 ± 49.8883 ml/100g/min, respectively (p = 0.1613).Dynamic 18F-FDG PET/CT and perfusion CT derived blood volume had similar capability to differentiate benign from malignant lung nodules.
Introduction
Bronchial artery embolisation (BAE) is an established treatment method for massive haemoptysis. The aim of this study is to evaluate the impact of BAE on in-hospital outcomes and ...long-term survival in patients with massive haemoptysis.
Methods
Retrospective review of all cases of acute massive haemoptysis treated by BAE between April 2000 and April 2012 with at least a 5 year follow up of each patient. Targeted BAE was performed in cases with lateralising symptoms, bronchoscopic sites of bleeding or angiographic unilateral abnormal vasculature. In the absence of lateralising symptoms or signs, bilateral BAE was performed.
Results
96 BAEs were performed in 68 patients. The majority (64 cases, 67%) underwent unilateral procedures. 83 (86.5%) procedures resulted in immediate/short term control of haemoptysis which lasted for longer than a month. The mean duration of haemoptysis free period after embolisation was 96 months. There were three major complications (cardio-pulmonary arrest, paraparesis and stroke). 38 (56%) patients were still alive at least 5 years following their BAE. Benign causes were associated with significantly longer haemoptysis free periods, mean survival 108 months compared to 32 months in patients with an underlying malignant cause (
p
= 0.005). An episode of haemoptysis within a month of the initial embolisation was associated reduced overall survival (
p
= 0.033).
Conclusion
BAE is effective in controlling massive haemoptysis. Long-term survival depends on the underlying pulmonary pathology. Strategies are required to avoid incomplete initial embolisation, which is associated with ongoing haemoptysis and high mortality despite further BAE.
Myocardial inflammation and injury occur during coronary artery bypass graft (CABG) surgery. We aimed to characterise these processes during routine CABG surgery to inform the diagnosis of type 5 ...myocardial infarction.
We assessed 87 patients with stable coronary artery disease who underwent elective CABG surgery. Myocardial inflammation, injury and infarction were assessed using plasma inflammatory biomarkers, high-sensitivity cardiac troponin I (hs-cTnI) and cardiac magnetic resonance imaging (CMR) using both late gadolinium enhancement (LGE) and ultrasmall superparamagnetic particles of iron oxide (USPIO).
Systemic humoral inflammatory biomarkers (myeloperoxidase, interleukin-6, interleukin-8 and c-reactive protein) increased in the post-operative period with C-reactive protein concentrations plateauing by 48 h (median area under the curve (AUC) 7530 interquartile range (IQR) 6088 to 9027 mg/L/48 h). USPIO-defined cellular myocardial inflammation ranged from normal to those associated with type 1 myocardial infarction (median 80.2 IQR 67.4 to 104.8 /s). Plasma hs-cTnI concentrations rose by ≥50-fold from baseline and exceeded 10-fold the upper limit of normal in all patients. Two distinct patterns of peak cTnI release were observed at 6 and 24 h. After CABG surgery, new LGE was seen in 20% (n = 18) of patients although clinical peri-operative type 5 myocardial infarction was diagnosed in only 9% (n = 8). LGE was associated with the delayed 24-h peak in hs-cTnI and its magnitude correlated with AUC plasma hs-cTnI concentrations (r = 0.33, p < 0.01) but not systemic inflammation, myocardial inflammation or bypass time.
Patients undergoing CABG surgery invariably have plasma hs-cTnI concentrations >10-fold the 99th centile upper limit of normal that is not attributable to inflammatory or ischemic injury alone. Peri-operative type 5 myocardial infarction is often unrecognised and is associated with a delayed 24-h peak in plasma hs-cTnI concentrations.
Diagnosis of coronavirus disease 2019 (COVID-19) can be challenging, especially when the real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) is not available or it is ...negative. In this study, we evaluated imaging and laboratory findings in a group of patients with a multidisciplinary diagnosis of COVID-19 pneumonia.
A total of 163 patients with a clinical diagnosis of COVID-19 pneumonia admitted to a specialised respiratory centre in Tehran, Iran were enrolled in this study. The distribution and characteristics of presenting radiological and laboratory findings were evaluated and the relationship to the outcome was investigated.
RT-PCR was positive in 92 patients. The diagnosis of COVID-19 in RT-PCR negative patients was made on clinical and radiological features (n=71) and 24 (14.7%) patients died of disease. The common computed tomography (CT) scan findings included ground-glass (94%) and consolidating opacification (12%), mainly in the lower lobes (90%). Peripheral and central lung changes were observed in 90% and 52% of patients, respectively. Lymphopenia, positive CRP, and raised LDH were present in 32%, 65%, and 96% of cases, respectively. A raised LDH of >500U/L was the best predictor of death in these patients (R
=0.6623; OR=24.4). Other markers of outcome included male gender, age (>50 years), lymphopenia, and severe CXR changes.
Diagnosis of COVID-19 can be challenging, and a multidisciplinary approach is often needed. Whilst RT-PCR is still the standard diagnostic test, a negative test should be interpreted with caution. Blood tests and imaging can be useful in the diagnosis, monitoring, and risk assessment in patients with COVID-19.
Biocompatibility of Acellular Human Pericardium Mirsadraee, Saeed, M.D., Ph.D; Wilcox, Helen E., Ph.D; Watterson, Kevin G., F.R.A.C.S ...
The Journal of surgical research,
12/2007, Volume:
143, Issue:
2
Journal Article
Peer reviewed
Background Previous studies have shown successful decellularization of human pericardium without affecting the major structural components and strength of the matrix. The aim of this study was to ...assess the biocompatibility and reseeding potential of the acellular human pericardial scaffold. Materials and methods Pericardia were treated sequentially with hypotonic buffer, sodium dodecyl sulfate, and a nuclease solution. The presence of cellular attachment factors after decellularization was evaluated using immunohistochemistry. The scaffold was seeded with dermal fibroblasts and cellular attachment to and numbers of cells penetrating were assessed over time. Biocompatibility was also evaluated following subcutaneous implantation into a mouse model for three months. Results After decellularization, the scaffold stained positively for fibronectin, but collagen IV and laminin staining was reduced. Seeded fibroblasts attached to the mesothelial surface and were visualized in the tissue within a week of seeding. The majority of fibroblasts in the tissue were viable and there was evidence of remodeling of the matrix. Analysis of the explanted tissues from mice showed that fresh/frozen and glutaraldehyde-fixed pericardia were encapsulated with a thick layer of inflammatory cells and fibrous tissue. In contrast, the decellularized scaffold was infiltrated with myofibroblasts, CD34+ cells and macrophages, indicating a healthy repair process. Compared with the glutaraldehyde-fixed tissue, the calcium content of the fresh/frozen and decellularized pericardia was negligible. Conclusions The pericardial scaffold was biocompatible in vitro and in the mouse model in vivo.
IntroductionSevere aortic stenosis is a major cause of morbidity and mortality. The existing treatment pathway for transcatheter aortic valve implantation (TAVI) traditionally relies on tertiary ...Heart Valve Centre workup. However, this has been associated with delays to treatment, in breach of British Cardiovascular Intervention Society targets. A novel pathway with emphasis on comprehensive patient workup at a local centre, alongside close collaboration with a Heart Valve Centre, may help reduce the time to TAVI.MethodsThe centre performing local workup implemented a novel TAVI referral pathway. Data were collected retrospectively for all outpatients referred for consideration of TAVI to a Heart Valve Centre from November 2020 to November 2021. The main outcome of time to TAVI was calculated as the time from Heart Valve Centre referral to TAVI, or alternative intervention, expressed in days. For the centre performing local workup, referral was defined as the date of multidisciplinary team discussion. For this centre, a total pathway time from echocardiographic diagnosis to TAVI was also evaluated. A secondary outcome of the proportion of referrals proceeding to TAVI at the Heart Valve Centre was analysed.ResultsMean±SD time from referral to TAVI was significantly lower at the centre performing local workup, when compared with centres with traditional referral pathways (32.4±64 to 126±257 days, p<0.00001). The total pathway time from echocardiographic diagnosis to TAVI for the centre performing local workup was 89.9±67.6 days, which was also significantly shorter than referral to TAVI time from all other centres (p<0.003). Centres without local workup had a significantly lower percentage of patients accepted for TAVI (49.5% vs 97.8%, p<0.00001).DiscussionA novel TAVI pathway with emphasis on local workup within a non-surgical centre significantly reduced both the time to TAVI and rejection rates from a Heart Valve Centre. If adopted across the other centres, this approach may help improve access to TAVI.
Abstract Objective Resolution and long-term functional effects of pulmonary emboli are unpredictable. This study was carried out to assess persisting vascular bed perfusion abnormalities and ...resolution of arterial thrombus in patients with recent pulmonary embolism (PE). Methods and materials 26 patients were prospectively evaluated by dynamic (4D) contrast enhanced CT perfusion dynamic pulmonary CT perfusion. Intermittent volume imaging was performed every 1.5-1.7 seconds during breath-hold using and perfusion values were calculated by maximum-slope technique. Thrombus load (modified Miller score; MMS) and ventricular diameter were determined. Perfusion maps were visually scored and correlated with residual endoluminal filling defects. Results The mean initial thrombus load was 13.1 ± 4.6 MMS (3-16), and 1.2 ± 2.1 MMS (0-8) at follow up. From the 24 CTPs with diagnostic quality perfusion studies, normal perfusion was observed in 7 (29%), and mildly-severely abnormal in 17 (71%). In 15 patients with no residual thrombus on follow up CTPA, normal perfusion was observed in 6, and abnormal perfusion in 9. Perfusion was abnormal in all patients with residual thrombus on follow up CTPA. Pulmonary perfusion changes were classified as reduced (n = 4), delayed (systemic circulation pattern; n = 5), and absent (no-flow; n = 5). The right ventricle was dilated in 12/25 (48%) at presentation, and normal in all 26 follow up scans. Weak correlation was found between initial ventricular dilatation and perfusion abnormality at follow up (r = 0.15). Conclusions Most patients had substantial perfusion abnormality at 3-6 months post PE. Abnormal perfusion patterns were frequently observed in patients and in regions with no corresponding evidence of residual thrombus on CTPA. Some defects exhibit delayed, presumed systemic, enhancement (which we have termed ‘stunned’ lung). CT perfusion provides combined anatomical and functional information about PE resolution.
Abstract Background Macrophages have a central role in the inflammatory response to myocardial infarction and predict subsequent clinical outcome. Ultrasmall superparamagnetic particles of iron oxide ...(USPIO) are an MRI contrast agent consisting of an iron oxide core surrounded by a dextran coat. They are small enough to migrate passively across the endothelium in regions of inflamed vasculature where they are engulfed by tissue macrophages and can be detected on T2* MRI. We aimed to examine temporal changes in cellular inflammation and tissue oedema in patients after acute myocardial infarction using USPIO-enhanced T2* and T2 mapping MRI. Methods 31 patients were followed up for 3 months after acute myocardial infarction. Repeated T2* and T2 maps were acquired with 3T MRI immediately before and 24 h after USPIO administration. Regions of interest were categorised into infarct, peri-infarct, and remote myocardial zones, and compared with other organs and tissues. Findings After one administration, USPIO enhancement was detected by changes in MRI R2* (1/T2*) in non-infarcted myocardium (50/s before enhancement vs 84/s 24 h after administration, p<0·0001), kidney (53 vs 172, p<0·0001), and blood pool (27 vs 124, p<0·0001) at 24 h, bone marrow until 4–9 days (276 vs 533, p<0·0001), and liver and spleen until 13–21 days (72 vs 152 p=0·0001 and 67 vs 148 p=0·0354, respectively). Histology confirmed co-localisation of iron and macrophages within infarcted tissue. After repeated administration, increased USPIO enhancement was detected by changes in R2* in the infarct zone, peaking at days 2–3 and persisting until days 10–16 compared with values at 3 months (88·5/s and 65·4 vs 39·5, p<0·0001 and p<0·0372, respectively). By contrast, T2-defined myocardial oedema in the infarct zone peaked at days 3–9 (59 ms) and remained increased at the 3 month follow-up timepoint compared with remote myocardium (49 ms vs 44, p=0·0007). Interpretation We have shown that myocardial macrophage activity can be detected with USPIO-enhanced MRI in the first 2 weeks after acute myocardial infarction. This pattern of cellular inflammation is distinct from the more prolonged myocardial oedema detectable with T2 mapping. USPIO-enhanced MRI holds promise as a non-invasive method of assessing myocardial cellular inflammation with potential application to diagnosis, risk stratification, and assessment of therapeutic interventions, not only after myocardial infarction but also in other inflammatory conditions affecting the heart. Funding British Heart Foundation.
Objectives
To review the role of imaging in the diagnosis of recurrent disease in previously treated non-small cell lung cancer (NSCLC) and discuss the imaging pitfalls.
Methods
A comprehensive ...review of published literature on CT and PET imaging of NSCLC recurrence was performed. Diagnostic and prognostic values are discussed. Representative imaging examples are illustrated.
Results
Up to 30% of NSCLC recurrences present as loco-regional, involving treated hemithorax and ipsilateral lymph nodes, while 70% present as metachronous distant metastases. CT and PET-CT play an important role in the early detection of recurrence; indications for imaging vary depending on pathological features.
Conclusion
Imaging plays a central role in the identification of recurrence and may predict prognosis.
Key Points
Lung cancer recurs after surgery in 30% to 75% of patients.
CT and PET-CT are crucial in identification of loco-regional recurrence.
Knowledge of potential pitfalls is essential, especially for parenchymal or nodal recurrence.
CT can diagnose metastases but further examinations (PET-CT, MRI) are often needed.
Morphological and functional imaging criteria may help in predicting recurrence.
PDF
