Multimodality Imaging of Aortitis

The cardiovascular pathologist in the aortic team

Aortic diseases require a multidisciplinary management for diagnosis, treatment and follow-up with better outcomes in referral centers using a team-based approach. The setting up of a multi-disciplinary aortic team for the discussion of complex cases has been already proposed; it is also supported by the ACC/AHA. Surgeons and radiologists, more or less other physicians such as cardiologists, geneticists, rheumatologists/internal medicine specialists and pathologists are involved into such a team. The role of the cardiovascular pathologist is to examine the aortic specimens, to diagnose and classify the aortic lesions. Herein, the role of the pathologist in the aortic team is discussed and the pathobiology of aortic diseases is reviewed for reference by pathologists. The aortic specimens are mainly obtained from emergency or elective surgical procedures on the thoracic aorta, less frequently from organ/tissue (including cardiac or heart valve) donors, post-mortem procedures or abdominal aortic surgery. In the last decade, together with the progress of medical sciences, the histological definitions and classifications of the aortic pathology are undergoing thorough revisions that are addressed to an etiopathogenetic approach because of possible clinico-pathological correlations, therapeutic and prognostic impact. Pathologists may also have an important role in research and teaching. Therefore, histological analyses of the aortic specimens require adequate sample processing and pathologist expertise because histology contributes to definite diagnosis, correct management of patients and even (in genetic diseases) families, but also to research in the challenging field of aortopathies.

Multimodality imaging to assess diagnosis and evaluate complications of large vesselarteritis

Different types of vasculitis can be distinguished according to the blood vessel's size that is preferentially affected: large-vessel, medium-vessel, and small-vessel vasculitides. Giant cell arteritis (GCA) and Takayasu's arteritis (TAK) are the main forms of large-vessel vasculitis, and may lead to lumen narrowing. Clinical manifestations of arterial narrowing on the short- and long term include vision loss, stroke, limb ischemia, and heart failure. Imaging tools are well established diagnostic tests for large-vessel vasculitis and may aid therapy monitoring in selected cases while providing important information regarding the occurrence of vascular damage, tissue and organ complications. This review aims to provide the current status of multimodality imaging for the diagnosis and identification of vascular complications in the field of large vessel vasculitis.

Multi-Modality Imaging in Vasculitis

Systemic vasculitides are a rare and complex group of diseases that can affect multiple organ systems. Clinically, presentation may be vague and non-specific and as such, diagnosis and subsequent management are challenging. These entities are typically classified by the size of vessel involved, including large-vessel vasculitis (giant cell arteritis, Takayasu's arteritis, and clinically isolated aortitis), medium-vessel vasculitis (including polyarteritis nodosa and Kawasaki disease), and small-vessel vasculitis (granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis). There are also other systemic vasculitides that do not fit in to these categories, such as Behcet's disease, Cogan syndrome, and IgG4-related disease. Advances in medical imaging modalities have revolutionized the approach to diagnosis of these diseases. Specifically, color Doppler ultrasound, computed tomography and angiography, magnetic resonance imaging, positron emission tomography, or invasive catheterization as indicated have become fundamental in the work up of any patient with suspected systemic or localized vasculitis. This review presents the key diagnostic imaging modalities and their clinical utility in the evaluation of systemic vasculitis.

Multimodal imaging in Ig G4- related aortitis: case report

We present the case of a 56-year-old patient with fever of unknown origin associated with chest and lumbar pain. Multimodality imaging revealed diffuse peri-aortitis in the thoracic aorta without involvement of the aortic valve, contributing substantially to the diagnosis of Ig G4-associated aortitis. Immunosuppressive therapy was started. Follow-up at five months with cardiac magnetic resonance imaging showed a reduction in the inflammatory process in the thoracic aorta.

Single centre experience of 120 patients with non-infectious aortitis: Clinical features, treatment and complications

BACKGROUND

Aortitis is an important form of vasculitis with significant risk of complications. Very few studies have provided detailed clinical phenotyping across the whole disease spectrum. Our primary aim was to look the clinical features, management strategies and complications associated with non-infectious aortitis.

METHODS

A retrospective review was performed on patients with diagnosis of noninfectious aortitis at the Oxford University hospitals NHS Foundation Trust. Clinicopathologic features were recorded including demographics, presentation, aetiology, laboratory, imaging findings, histopathology, complications, treatment, and outcome.

RESULTS

We report the data on 120 patients (59% females). Systemic inflammatory response syndrome constituted the most common presentation (47.5%). 10.8% were diagnosed following a vascular complication (dissection or aneurysm). All patients (n = 120) had raised inflammatory markers (median ESR 70.0 mm/h and CRP 68.0 mg/L). Isolated aortitis subgroup (15%) had significantly higher likelihood of presenting with vascular complications and challenging to diagnose due to non-specific symptoms. Prednisolone (91.5%) and methotrexate (89.8%) were the most used treatment. 48.3% developed vascular complications during the disease course including ischaemic complications (25%), aortic dilatation and aneurysms (29.2%) and dissection (4.2%). Risk of dissection was higher in the isolated aortitis subgroup at 16.6% compared to all other types of aortitis at 1.96%.

CONCLUSION

Risk of vascular complications is high in non-infectious aortitis patients during disease course, hence early diagnosis and appropriate management is key. DMARDs such as Methotrexate appear to be effective, nonetheless there remain gaps in evidence for longer-term management of relapsing disease. Dissection risk seems much higher for patients with isolated aortitis.

Decisive diagnostic clue for infectious abdominal aortic aneurysm caused by Arthrobacter russicus in a diabetic elderly woman with renal dysfunction: A case report and literature review

Infectious aortic aneurysm (IAA) can be a rare but potentially fatal sequela of infectious inflammatory disease of the aortic wall with a high incidence of rupture. The definitive diagnosis is based on vascular imaging of the aneurysm using contrast-enhanced computed tomography (CE-CT) and identification of the causative microorganism from positive blood cultures (BCs). However, IAA remains extremely difficult to diagnose and treat in patients with prior antimicrobial treatment or with renal dysfunction. Here we describe a case of an 85-year-old woman with IAA caused by Arthrobacter russicus presenting with abdominal pain and fever that was initially diagnosed as a presumptive urinary tract infection and treated with empiric antimicrobial therapy. However, persistent abdominal pain with increased serological inflammation necessitated further evaluation. Unenhanced multimodality imaging considering the renal dysfunction revealed infectious aortitis of the infrarenal abdominal aorta, together with the initial culture results, leading to the tentative diagnosis of Klebsiella pneumoniae aortitis. Thereafter, serial monitoring with unenhanced magnetic resonance angiography (MRA) using thin-slab maximum intensity projection (TS-MIP) revealed acute aortic expansion strongly suggestive of a pseudoaneurysm that was successfully treated with early surgical repair under adequate infection control. Despite negative Gram staining and tissue culture results for the excised aortic wall, a definitive diagnosis of IAA secondary to A. russicus rather than K. pneumoniae was finally made by confirming the histologic findings consistent with IAA and the identification of A. russicus 16S rRNA on the resected aortic wall. The patient also developed a vascular graft infection during the postoperative course that required long-term systemic antimicrobial therapy. This case highlights the value of unenhanced MRA in the early detection of IAA in patients with renal dysfunction and the importance of a molecular diagnosis for identifying the causative microorganism in cases of culture- or tissue-negative IAA.

Combined modality PET/MR for the detection of severe large vessel vasculitis

Background

Large vessel vasculitis (LVV) can be characterized based on symptom severity, and this characterization helps clinicians decide upon treatment approach. Our aim was to compare the imaging findings of combined modality positron emission tomography/magnetic resonance (PET/MR) and inflammatory markers between severe and non-severe LVV. A retrospective query was performed to identify all patients with LVV who underwent PET/MR at our institution between January 2015 and January 2021.

Results

Eleven patients (nine females; age 62.2 ± 16.4 years) underwent 15 PET/MR scans. Positivity was defined by findings indicative of active LVV on each modality: PET positive if vessel metabolic activity > liver metabolic activity; MR positive if wall thickening or contrast enhancement. When positive PET or positive MR findings were considered a positive scan, LVV patients with severe disease (n = 9 scans) showed a higher number of positive scans (n = 9) compared to the number of positive scans in non-severe patients (n = 3) (p < 0.05). The sensitivity and specificity for the detection of severe LVV were 1.00 and 0.50, respectively. When only the presence of both positive PET and positive MR findings were considered a positive scan, inflammatory marker levels were not significantly different between severe and non-severe LVV groups (severe: erythrocyte sedimentation rate (ESR) = 9.8 ± 10.6 mm/h; C-reactive protein (CRP) = 0.6 ± 0.4 mg/dL) (non-severe: ESR = 14.3 ± 22.4 mm/h; CRP = 0.5 ± 0.6 mg/dL). Blood- and liver-normalized maximum standardized uptake values were not significantly different between severe and non-severe patients (1.4 ± 0.3 vs 1.5 ± 0.4; 1.1 ± 0.4 vs 1.0 ± 0.3, respectively).

Conclusions

Because of the differences observed, PET/MR appears to be better suited to facilitate the characterization of LVV as severe or non-severe compared to inflammatory marker measurements and quantitative measurements of metabolic activity. Qualitative assessment of PET and MR positivity by 18F-fluorodeoxyglucose PET/MR may be able to supplement clinical symptoms-based LVV classification decisions and may be helpful when clinical symptoms overlap with other disease processes.

Large vessel vasculitis with rare presentation of acute rhabdomyolysis: A case report and review of literature

BACKGROUND

Musculoskeletal involvement in primary large vessel vasculitis (LVV), including giant cell arteritis and Takayasu's arteritis (TAK), tends to be subacute. With the progression of arterial disease, patients may develop polyarthralgia and myalgias, mainly involving muscle stiffness, limb/jaw claudication, cold/swelling extremities, etc. Acute development of rhabdomyolysis in addition to aortic aneurysm is uncommon in LVV. Herein, we report a rare case of LVV with the first presentation of acute rhabdomyolysis.

CASE SUMMARY

A 70-year-old Asian woman suffering from long-term low back pain was hospitalized due to limb claudication, dark urine and an elevated creatine kinase (CK) level. After treatment with fluid resuscitation and antibiotics, the patient remained febrile. Her workup showed persistent elevated levels of inflammatory markers, and imaging studies revealed an aortic aneurysm. A decreasing CK was evidently combined with elevated inflammatory markers and negativity for anti-neutrophilic cytoplasmic antibodies. LVV was suspected and confirmed by magnetic resonance angiography and positron emission tomography with 18F-fluorodeoxyglucose/computed tomography. With a favourable response to immunosuppressive treatment, her symptoms resolved, and clinical remission was achieved one month later. However, after failing to follow the tapering schedule, the patient was readministered 25 mg/d prednisolone due to disease relapse. Follow-up examinations showed decreased inflammatory markers and substantial improvement in artery lesions after 6 mo of treatment. At the twelve-month follow-up, she was clinically stable and maintained on corticosteroid therapy.

CONCLUSION

An exceptional presentation of LVV with acute rhabdomyolysis is described in this case, which exhibited a good response to immunosuppressive therapy, suggesting consideration for a differential diagnosis when evaluating febrile patients with myalgia and elevated CK. Timely use of high-dose steroids until a diagnosis is established may yield a favourable outcome.

Aortitis is an under-recognized manifestation of antiphospholipid syndrome: A case report and literature review

Aortitis is a classic manifestation of large vessel vasculitis. Antiphospholipid syndrome (APS), sometimes known as Hughes syndrome, is an acquired autoimmune disorder that manifests clinically as recurrent venous or arterial thrombosis. Patients with APS may also suffer from various underlying diseases, most frequently systemic lupus erythematosus (SLE). Catastrophic antiphospholipid syndrome (CAPS) is a rare but serious complication of APS characterized by failure of several organs due to diffuse microcirculatory thrombi. Its main manifestations involve the kidneys, lungs, heart and central nervous system, and require early diagnosis and rapid therapeutic management. While APS can affect virtually any blood vessel, aortitis is not a known symptom of APS. We report the case of a 36-year-old patient with APS and SLE who presented with CAPS during pregnancy, with no concomitant SLE flare. The first manifestation of CAPS was aortitis, preceding renal, cardiac and haematological manifestations. The outcome was favourable with combined treatment including corticosteroids, anticoagulants, plasma exchange and rituximab. We then carried out a literature search for papers describing the presence of aortitis in APS and/or SLE. In the cases of aortic involvement identified in the literature, including another case of CAPS, the occurrence of aortitis in SLE, often associated with the presence of antiphospholipid antibodies/APS, suggests that aortitis should be considered as an under-recognized manifestation and potential non-criterion feature of APS.

MDCT Imaging of Non-Traumatic Thoracic Aortic Emergencies and Its Impact on Diagnosis and Management—A Reappraisal

Non-traumatic thoracic aorta emergencies are associated with significant morbidity and mortality. Diseases of the intimomedial layers (aortic dissection and variants) have been grouped under the common term of acute aortic syndrome because they are life-threatening conditions clinically indistinguishable on presentation. Patients with aortic dissection may present with a wide variety of symptoms secondary to the pattern of dissection and end organ malperfusion. Other conditions may be seen in patients with acute symptoms, including ruptured and unstable thoracic aortic aneurysm, iatrogenic or infective pseudoaneurysms, aortic fistula, acute aortic thrombus/occlusive disease, and vasculitis. Imaging plays a pivotal role in the patient’s management and care. In the emergency room, chest X-ray is the initial imaging test offering a screening evaluation for alternative common differential diagnoses and a preliminary assessment of the mediastinal dimensions. State-of-the-art multidetector computed tomography angiography (CTA) provides a widely available, rapid, replicable, noninvasive diagnostic imaging with sensitivity approaching 100%. It is an impressive tool in decision-making process with a deep impact on treatment including endovascular or open surgical or conservative treatment. Radiologists must be familiar with the spectrum of these entities to help triage patients appropriately and efficiently. Understanding the imaging findings and proper measurement techniques allow the radiologist to suggest the most appropriate next management step.

Vessel inflammation and morphological changes in patients with large vessel vasculitis: a retrospective study

OBJECTIVE

The aim was to identify any association between imaging signs of vessel wall inflammation (positron emission tomography-CT (PET-CT) score and CT/MR wall thickening) and synchronous and subsequent vascular damage (stenoses/dilations) in patients with large vessel vasculitis (LVV).

METHODS

Consecutive patients with LVV referred to a tertiary centre in 2007-2020 with baseline PET-CT and morphological imaging (CT/MR angiography) performed within 3 months were included. All available PET-CT and CT/MR scans were reviewed to assess PET-CT uptake (4-point semi-quantitative score), wall thickening, stenoses and dilations for 15 vascular segments. The associations of baseline PET score and CT/MR wall thickening with synchronous and incident stenoses/dilations at CT/MR performed 6-30 months from baseline were evaluated in per-segment and per-patient analyses. Respective areas under the receiver operating characteristic curve (AUC) were calculated.

RESULTS

We included 100 patients with LVV (median age: 48 years, 22% males). Baseline PET score and wall thickening were strongly associated (Cuzick non-parametric test for trend across order groups (NPtrend) <0.001). The association with synchronous stenoses/dilations was weak for PET score (NPtrend=0.01) and strong for wall thickening (p<0.001). In per-patient analyses, sensitivity/specificity for ≥1 synchronous stenoses/dilations were 44%/67% for PET score ≥2 and 66.7%/60.5% for wall thickening. Subsequent CTs/MRs were available in 28 patients, with seven incident stenoses/dilations. Baseline PET score was strongly associated with incident stenoses/dilations (p=0.001), while baseline wall thickening was not (p=0.708), with AUCs for incident stenoses/dilations of 0.80 for PET score and 0.52 for wall thickening.

CONCLUSION

PET score and wall thickening are strongly associated, but only baseline PET score is a good predictor of incident vessel wall damage in LVV.

ACR Appropriateness Criteria® Noncerebral Vasculitis

Noncerebral vasculitis is a wide-range noninfectious inflammatory disorder affecting the vessels. Vasculitides have been categorized based on the vessel size, such as large-vessel vasculitis, medium-vessel vasculitis, and small-vessel vasculitis. In this document, we cover large-vessel vasculitis and medium-vessel vasculitis. Due to the challenges of vessel biopsy, imaging plays a crucial role in diagnosing this entity. While CTA and MRA can both provide anatomical details of the vessel wall, including wall thickness and enhancement in large-vessel vasculitis, FDG-PET/CT can show functional assessment based on the glycolytic activity of inflammatory cells in the inflamed vessels. Given the size of the vessel in medium-vessel vasculitis, invasive arteriography is still a choice for imaging. However, high-resolution CTA images can depict small-caliber aneurysms, and thus can be utilized in the diagnosis of medium-vessel vasculitis. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Multimodality Imaging of Large Vessel Vasculitis, From the AJR Special Series on Inflammation

Large vessel vasculitis (LVV) is a non-infectious inflammation of the large vessels, including the aorta and its main branches. Imaging plays an essential role in diagnosing LVV, given the challenges of tissue biopsy. This article reviews the types of LVV, and the multimodality imaging tools available to establish the diagnosis in patients with LVV. The cornerstone of imaging diagnosis is morphologic assessment using grey-scale ultrasound, combined grey-scale US with color Doppler US, CTA, or MRA. In the last decade, substantial progress has been made in functional and molecular imaging with FDG PET/CT for the diagnosis of LVV. Investigation is ongoing to develop novel MRA techniques and new PET tracers to assess disease activity and to differentiate the various vasculitides. An algorithm is provided to guide imaging technique selection based on the patient's specific clinical presentation.

Systemic vasculitides and the role of multitechnique imaging in the diagnosis

Vasculitis, a systemic disease characterised by inflammation of the blood vessels, remains challenging to diagnose and manage. Vessel size has been the basis for classifying systemic vasculitides. Imaging plays a vital role in diagnosing this challenging disease. This review article aims (a) to summarise up-to-date literature in this field, as well as include classification updates and (b) to review available imaging techniques, recent advances, and emphasis on imaging findings to diagnose large vessel vasculitides.

Granulocyte colony stimulating factor-associated aortitis evaluated via multiple imaging modalities including vascular echography: a case report

Background

Granulocyte colony stimulating factor (G-CSF) preparations are used for patients with granulocytopenia, especially to prevent febrile neutropenia. Arteritis has been recognized as a side effect of G-CSF treatment; however, there are no clear diagnostic criteria or treatment guidelines because not enough cases have been reported. Present case showed one of the diagnostic and treatment selection methods via multiple imaging modality including vascular echography.

Case summary

A 52-year-old woman underwent chemotherapy for ovarian cancer and received G-CSF because of myelosuppression. The patient experienced high and remittent fever that persisted during treatment using antibiotics and acetaminophen. Enhanced computed tomography revealed thickening of the tissue around the aortic arch and abdominal aorta. Echography of the abdominal aorta revealed thickening of the wall and a hypoechoic region around the aorta. Gadolinium-enhanced magnetic resonance imaging and ¹⁸F-fludeoxyglucose positron emission tomography also revealed that the inflammation was localized to the lesion. A suspicion of G-CSF-associated aortitis was based on the patient’s history and the exclusion of other diseases that might have caused the aortitis. Her condition rapidly improved after starting corticosteroid treatment.

Discussion

The differential diagnosis in similar cases should consider immune diseases that cause large-vessel arteritis (Takayasu arteritis, giant cell arteritis, and another vasculitis), infection, drug-induced disease, and immunoglobulin G4-related disease. The use of different imaging modalities, including vascular echography, helped guide the diagnosis and follow-up. It is necessary to evaluate the patient’s general condition before the selection of treatments.

Aortic dissection and accelerated aneurysmal degeneration in a patient with giant cell arteritis

Giant cell arteritis (GCA) is associated with nonatheromatous aortic pathology. Here we present a case in which a 76-year-old woman with a biopsy-proven history of GCA and a previous repair of her ascending aortic aneurysm presents with an acute dissection of a 4-cm aneurysm in the descending thoracic aorta. It was treated using endovascular techniques. This report adds to a growing body of evidence that GCA is a risk factor for aortic dissection and nonatheromatous aortic aneurysms.

The role of cardiac imaging in the management of non-ischemic cardiovascular diseases in human immunodeficiency virus infection

Infection with human immunodeficiency virus (HIV) has become the pandemic of the new century. About 36.9 million people are living with HIV worldwide. The introduction of antiretroviral therapy in 1996 has dramatically changed the global landscape of HIV care, resulting in significantly improved survival and changing HIV to a chronic disease. With near-normal life expectancy, contemporary cardiac care faces multiple challenges of cardiovascular diseases, disorders specific to HIV/AIDS, and those related to aging and higher prevalence of traditional risk factors. Non-ischemic cardiovascular diseases are major components of cardiovascular morbidity and mortality in HIV/AIDS. Non-invasive cardiac imaging plays a pivotal role in the management of these diseases. This review summarizes the non-ischemic presentation of the HIV cardiovascular spectrum focusing on the role of cardiac imaging in the management of these disorders.

Large vessel vasculitis secondary to granulocyte-colony stimulating factor

Aortitis is a rare entity that may cause fever of unknown origin. This entity has a wide various etiologies, which main cause is rheumatologic, but not only. Iatrogenia has also been described, including chemotherapy and supporting treatment (like granulocyte-colony stimulating factor in oncological patients. The evidence in favour of this pharmacological link is growing. The differential diagnosis of fever, in febrile neutropenia setting, can be difficult to itemize.

Etiology, Diagnosis and Management of Aortitis

Aortitis includes conditions with infectious or non-infectious etiology, characterized by inflammatory changes in one or more layers in aortic wall. Age at onset, geographic predilections, distribution and pattern of involvement in aorta, its branches and pulmonary arteries, and systemic associations provide a clue to etiology. Clinical presentations are often non-specific. An integrated approach including clinical, laboratory and imaging assessment is essential to confirm diagnosis and plan treatment. Assessment of disease activity is the key as it influences timing and outcome of treatment. Markers of activity include clinical, laboratory and imaging. Medical management remains the first-line therapy. Revascularization is indicated in the presence of hemodynamically significant stenosis and inactive disease. In the presence of flash pulmonary edema, left ventricular dysfunction or hypertensive encephalopathy, revascularization is performed irrespective of disease activity. Endovascular management is favored over surgery due to its high success and low restenosis rates. Symptomatic aneurysmal disease is usually managed by surgery.

Imaging of the aortic root on high-pitch non-gated and ECG-gated CT: awareness is the key!

The aortic pathologies are well recognized on imaging. However, conventionally cardiac and proximal aortic abnormalities were only seen on dedicated cardiac or aortic studies due to need for ECG gating. Advances in CT technology have allowed motionless imaging of the chest and abdomen, leading to an increased visualization of cardiac and aortic root diseases on non-ECG-gated imaging. The advances are mostly driven by high pitch due to faster gantry rotation and table speed. The high-pitch scans are being increasingly used for variety of clinical indications because the images are free of motion artifact (both breathing and pulsation) as well as decreased radiation dose. Recognition of aortic root pathologies may be challenging due to lack of familiarity of radiologists with disease spectrum and their imaging appearance. It is important to recognize some of these conditions as early diagnosis and intervention is key to improving prognosis. We present a comprehensive review of proximal aortic anatomy, pathologies commonly seen at the aortic root, and their imaging appearances to familiarize radiologists with the diseases of this location.

18F-Fluorodeoxyglucose PET/Computed Tomography in the Diagnosis and Monitoring of Giant Cell Arteritis

18F-Fluorodeoxyglucose (FDG) PET/computed tomography (CT) is a highly accurate diagnostic tool for large vessel vasculitis (LVV) and is one of the recommended imaging modalities for confirmation of the diagnosis. This article focuses on the role of FDG-PET/CT in LVV diagnosis and disease monitoring, mainly focusing on giant cell arteritis; in particular, the diagnostic accuracy, diagnostic criteria, the potential pitfalls in the interpretation of large vessel FDG uptake, and the clinical indication compared with other imaging modalities are discussed.

Coronary arteritis: a case series

Background

The present article describes two cases of patients with coronary arteritis (CA) whose identification of CA diagnosis (late vs. early) resulted in different clinical courses and outcomes.

Case summary

Case 1 is a 53-year-old woman with multiple coronary risk factors who was admitted with acute coronary syndrome (ACS) and significant stenosis in the left main trunk (LMT). Although clues suggested arteritis (LMT lesion without any other stenosis, occlusion of left internal thoracic artery, etc.), the diagnosis of CA (coronary involvement of unclassified arteritis) was delayed and revascularization, including coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI), was performed under uncontrolled inflammatory status. As a result, Case 1 experienced repeated ACS episodes due to graft failure and in-stent restenosis, and repeatedly underwent PCI. Case 2 is a 76-year-old woman with no significant coronary risk factors who was admitted with ACS. This patient was successfully diagnosed with coronary involvement of Takayasu arteritis before revascularization. Coronary artery bypass grafting was performed after stabilizing inflammation with prednisolone, and the patient remains angina-free beyond 1-year post-CABG. In both cases, intravascular imaging clearly identified the localization and degree of inflammation related to CA by demonstrating specific findings (ambiguous typical three-layer structure of arterial wall and extended low-echoic areas within adventitia).

Discussion

Accurate and early diagnosis with meticulous diagnostic and therapeutic strategies appear to be important for favourable clinical outcomes in the medical treatment of patients with coronary involvement of arteritis. Intravascular imaging has the potential to contribute to optimizing clinical management of CA.

Acute aortic syndromes: diagnosis and management, an update

Acute aortic syndromes (AAS) encompass a constellation of life-threatening medical conditions including classic acute aortic dissection (AAD), intramural haematoma, and penetrating atherosclerotic aortic ulcer. Given the non-specific symptoms and physical signs, a high clinical index of suspicion is necessary to detect the disease before irreversible lethal complications occur. In order to reduce the diagnostic time delay, a comprehensive flowchart for decision-making based on pre-test sensitivity of AAS has been designed by the European Society of Cardiology guidelines on aortic diseases and should be thus applied in the emergency scenario. When the definitive diagnosis is made, prompt and appropriate therapeutic interventions should be undertaken if indicated by a highly specialized aortic team. Urgent surgery for AAD involving the ascending aorta (Type A) and medical therapy alone for AAD not involving the ascending aorta (Type B) are typically recommended. In complicated Type B AAD, thoracic endovascular aortic repair (TEVAR) is generally indicated. On the other hand, in uncomplicated Type B AAD, pre-emptive TEVAR rather than medical therapy alone to prevent late complications, while intuitive, requires further study in randomized cohorts. Finally, it should be highlighted that there is an urgent need to increase awareness of AAS worldwide, including dedicated education/prevention programmes, and to improve diagnostic and therapeutic strategies, outcomes, and lifelong surveillance.

Aortoenteric fistula secondary to an Inflammatory Abdominal Aortic Aneurysm

Primary aortoenteric fistulas are rare, with the annual incidence of such fistulas estimated to be 0.007 per million. The most common predisposing conditions for primary aortoenteric fistulas are atherosclerotic abdominal aortic aneurysms or penetrating atherosclerotic ulcers. We illustrate a rare case of an inflammatory aortic aneurysm causing a primary aortic fistula, with a direct fistulous jet from the aorta to the bowel with resultant catastrophic bleeding. In contrast to atherosclerotic aneurysms, most inflammatory aneurysms are symptomatic and show dense perianeurysmal fibrosis and periaortic wall thickening. A direct jet of contrast extravasation from the aorta into a bowel loop, while rarely seen, remains the most specific sign of a primary aorta-enteric fistula. A comprehensive literature review of the clinical presentation, imaging features, and differential diagnosis of a primary aortoenteric fistula are also discussed.

3D black-blood 3T-MRI for the diagnosis of abdominal large vessel vasculitis

OBJECTIVES

To assess the value of a T1-3D black-blood turbo spin echo (TSE) sequence for the diagnosis of abdominal large vessel vasculitis (LVV).

MATERIALS AND METHODS

The study included 20 patients with abdominal LVV and 17 controls, who underwent a 3T-MRI scan using a modified T1-3D volumetric isotropic TSE acquisition and a segmented T1-3D turbo field echo sequence (T1-mVISTA/T1-eTHRIVE). Two radiologists independently analyzed the aorta for concentric contrast enhancement, concentric wall thickening, image quality, and flow artifact intensity (CCE/CWT/IQ/FAI; 4-point scales). The mean aortic wall thickness (MAWT) in post-contrast T1-mVISTA was compared between patients and controls.

RESULTS

IQ of T1-mVISTA was rated good to excellent in 91.5% of 282 evaluated vessel segments with no or minor FAI present in 85.5%. The inter-observer reproducibility for the identification of CCE/CWT on T1-mVISTA was 0.92 and 0.93 (p < 0.001). The distribution of segmental inflammation in T1-mVISTA significantly correlated with T1-eTHRIVE (CCE, κ = 0.768; CWT, κ = 0.715; p < 0.001), resulting in a sensitivity, specificity, and positive predictive value of 100%, 81.3%, and 83.3%. The MAWT significantly differed between patients and controls (3.29 ± 0.81 vs. 2.24 ± 0.45 mm; p < 0.001).

CONCLUSIONS

T1-mVISTA enables the evaluation of the MAWT and allows the detection of abdominal LVV.

KEY POINTS

• 3D T1w-mVISTA accurately depicted the large abdominal vessels. • 3D T1w-mVISTA enables accurate measurements of the abdominal aortic wall thickness. • 3D T1w-mVISTA is useful for the detection of abdominal LVV.

Characteristics and outcomes in a prospective cohort of patients with histologically diagnosed aortitis

Objectives

Our aim was to evaluate characteristics and prospective adverse aortic outcomes in a cohort of patients with non-infectious histological aortitis.

Methods

Patients with histological aortitis, diagnosed at the Ottawa Hospital after surgical repair of thoracic aortic aneurysms or dissections, consented to enrolment in a prospective observational cohort. Patients were assessed for an underlying inflammatory condition and followed prospectively with periodic clinical, laboratory and radiographic assessments. Aortic outcomes during follow-up included significant events, defined as new thoracic or abdominal aortic aneurysms, dissections, ruptures or other complications requiring aortic intervention, in addition to aortic branch ectasias, aneurysms and stenosis.

Results

Sixteen patients with histological aortitis from surgical procedures performed between 2010 and 2017 were included; nine had idiopathic and seven had secondary aortitis. Idiopathic patients were more likely to have smoked (100 vs 43%, P = 0.02) and had more associated arch or descending aortic aneurysms on pre-operative baseline imaging compared with secondary aortitis (6 vs 0, P = 0.01). At the median 3.6 years of follow-up, eight patients (50%) had 10 significant aortic events. The incidence of aortic dissection was higher in the first year post-surgery, compared with subsequent years, whereas incident aneurysms occurred throughout follow-up. Elevated inflammatory markers during follow-up trended towards association with accumulation of severe aortic damage.

Conclusion

This is the first reported prospective study in patients with histological aortitis. Within the limitations of a small cohort, we report a high incidence of aortic complications. Studies with a larger sample size and longer follow-up are needed to corroborate these findings.

Detection of Inflammatory Aortopathies Using Multimodality Imaging

Diagnosis of the inflammatory aortopathies and importantly, their distinction in the later stages of disease from genetically mediated or acquired (degenerative) aortopathy remains a challenging clinical problem. Historically, the diagnosis of inflammatory aortopathy has required tissue sampling and pathological assessment. Although histological diagnosis remains an important diagnostic criterion, the ability to obtain sufficient tissue samples is problematic and requires invasive approaches that pose important risk. Continuing refinement in the capabilities of multimodality imaging, including ultrasound, computed tomography, magnetic resonance imaging, and positron emission tomography provides important insights into the broad spectrum of disease which comprise the inflammatory aortopathies. This review examines the current and emerging role of multimodality imaging in the evaluation of aortitis.

Three-dimensional fat-saturated T1-weighted Cartesian volumetric interpolated breath-hold examination (VIBE) for the diagnosis of aortitis in patients with suspected large vessel vasculitis: a comparative study with 18F-FDG PET applying fully integrated PET/MRI

AIM

To evaluate the feasibility of T1-weighted (T1W) three-dimensional (3D) fat saturated Cartesian volumetric interpolated breath-hold examination (VIBE) magnetic resonance imaging (MRI) sequence for the diagnosis of aortitis in patients with suspected large vessel vasculitis (LVV) applying fully integrated 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (¹⁸F-FDG) positron-emission tomography (PET)/MRI.

MATERIAL AND METHODS

Fourteen patients with aortitis and 14 patients with a negative study for aortitis using ¹⁸F-FDG PET as the standard of reference for the evaluation of inflammatory aortic involvement were included retrospectively. All patients were imaged at 3 T using T1W VIBE pre- and post-contrast. Four aortic segments were evaluated for image quality (IQ), diagnostic confidence (DC), and the degree of inflammatory activity (IA) using a Likert scale. Binomial and generalised estimating equation model tests were used to assess the diagnostic performance of T1W VIBE. Cohen's k was applied to test for interobserver reproducibility with respect to IA. Spearman's rank correlation coefficient was calculated to examine correlations between IQ, DC, IA, and PET results.

RESULTS

On a patient- and segment-based analysis, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 85.7% and 59.8%, 100% and 100%, 100% and 100%, 87.5% and 68%, and 92.9% and 82.1%, respectively. IQ and DC were acceptable to good in all examinations and substantial interobserver agreement was observed for IA (Cohen's k = 0.69). IQ and DC as well as IA and ¹⁸F-FDG vessel wall uptake were significantly correlated (r=0.763 and 0.679, respectively; p<0.0001).

CONCLUSION

T1W 3D fat saturated VIBE MRI allows diagnosis of aortitis and may aid in the management of patients with suspected LVV.

Comparative study of 18F-FDG PET/CT and CT angiography in detection of large vessel vasculitis

OBJECTIVE

Compare ¹⁸F-FDG PET/CT and CTangio in the diagnosis of extracraneal large vessel involvement in patients with suspicion of large vessel vasculitis (LVV).

MATERIAL AND METHODS

A retrospective database reviewed 59 patients with clinical suspicion of LVV undergoing ¹⁸F-FDG PET/CT and CTangio. In 55 patients PET/TC and CTangio were done simultaneously in the same machine and in 4 patients with a scan interval of<1 month. PET/CT analyses included qualitatively and quantitative analysis (ratio SUVmax ¹⁸F-FDG vessel/SUVmax liver). CTangio was assessed for concentric mural thickening, contrast wall enhancement and structural vascular changes as potential complications of vasculitis.

RESULTS

¹⁸F-FDG PET/CT and CTangio show high specificity (97.2%) for LVV diagnosis, with an excellent sensitivity for ¹⁸F-FDG PET/CT (95.6%) and lower for CTangio (60.9%), which leads to a high negative predictive value for ¹⁸F-FDG PET/CT (97.2%) and a high false negative rate for CTangio (39.1%). A 70% concordance between ¹⁸F-FDG PET/CT and CTangio was obtained (Kappa index 0.70± 0.095 (P<.001).

CONCLUSION

The results show the greater potential of ¹⁸F-FDG PET/CT for the detection and extension of LVV. Therefore, ¹⁸F-FDG PET/CT should be exploited to the maximum and consider as the first line imaging technique in the extracranial diagnosis of LVV and its possible association with polymyalgia rheumatica. The addition of CTangio could be more indicated in patients with Takayasu arteritis and in long-standing and/or severe vasculitis since it increases the accuracy in the detection of possible vascular complications.

Assessment of disease activity in Takayasu arteritis: A quantitative study with computed tomography angiography

BACKGROUND

Identifying disease activity in Takayasu arteritis (TAK) is challenging. This study aimed to investigate the value of quantitative characterization with computed tomography angiography in the assessment of disease activity in patients with TAK.

METHODS

We retrospectively analysed the data on 162 aortic CT angiography from 140 TAK patients. Patients were categorized based on disease activity according to the National Institutes of Health criteria into two groups: active disease group (n = 65) and inactive disease group (n = 97).

RESULTS

Patients with active TAK had a thicker wall compared with patients with inactive TAK (5.2 ± 2.4 mm vs. 2.5 ± 0.8 mm, p < 0.001). The relative post-contrast enhancement ratio of the thickened wall was higher in active TAK than in inactive TAK (1.5 ± 0.3 vs. 1.1 ± 0.2, p < 0.001). Given a thickness cutoff of 3.3 mm, sensitivity for active-phase TAK was 83.1%, specificity 89.7%, positive predictive value 84.4%, and negative predictive value 88.8%. With a relative post-contrast enhancement ratio cutoff of 1.2, sensitivity for active-phase TAK was 89.2%, specificity 76.3%, positive predictive value 71.6%, and negative predictive value 91.3%. In receiver-operating characteristic curves comparison, maximal wall thickness and relative post-contrast enhancement ratio were superior to C-reactive protein and erythrocyte sedimentation rate for determining active phase disease (p < 0.05).

CONCLUSIONS

Quantitative characterization with CT angiography was a useful tool to assess disease activity in TAK patients. Maximal wall thickness and relative post-contrast enhancement ratio have a high sensitivity and specificity for detecting TAK activity.

Progression of atherosclerosis versus arterial stiffness with age within and between arteries in systemic lupus erythematosus

The progression of atherosclerosis versus arterial stiffness with age within and between arteries has not been defined. Systemic lupus erythematosus (SLE) is a human model of accelerated arterial disease that may permit this determination. 76 SLE patients (69 women, age 37 ± 12 years) and 26 age-and-sex-matched controls (22 women, age 34 ± 11 years) underwent transesophageal echocardiography and carotid ultrasonography for assessment of atherosclerosis [plaques and intima-media thickening (IMT)] and arterial stiffness [increased pressure-strain elastic modulus (PSEM)] of the descending thoracic aorta and carotid arteries. Since IMT is highly associated with plaques, IMT was used as a marker of atherosclerosis to assess its progression in relation with age and PSEM. Aortic and carotid plaques, IMT, and PSEM were greater in patients than in controls (all p ≤ 0.05). Within the aorta and within the carotid arteries, the average percent increases per decade of age for IMT versus PSEM were similar in patients (8.55% versus 9.33% and 3.39% versus 2.46%, respectively) and controls (5.53% versus 6.60% and 4.75% versus 3.49%, respectively) (all p ≥ 0.58). However, in SLE patients, the average percent increases per decade of age for IMT and PSEM were higher in the aorta than in the carotid arteries (8.55% and 9.33% versus 3.39% and 2.46%, respectively, both p ≤ 0.03). In patients with SLE, atherosclerosis and arterial stiffness progress with age parallel to each other within arteries, but divergently between arteries with different anatomy and hemodynamics.

Incidence of Aortitis in Surgical Specimens of the Ascending Aorta Clinical Implications at Follow-Up

The objectives of this study are to evaluate the incidence of aortitis on a surgical population, establish any relationship with systemic diseases, verify early and late surgical results and provide clinical and radiological follow-up to determine factors potentially predicting progression of the disease and influencing late outcome. From 2009 to 2017, 237 patients underwent elective operations on the ascending aorta. Segments of the excised tissues were routinely sent for histologic evaluation, providing adequate data in 178 (75%) for a clinical and pathologic correlation. Patients with aortitis (Group 1) (n = 26) were compared with 152 with atherosclerotic or degenerative disease (Group 2). Incidence of aortitis was 15%, being clinically isolated in 73%. In 24 patients (92%), a giant cell aortitis was found. Actuarial survival at 3 years is 88% in Group 1 and 98% in Group 2 and 74% and 98% at 5 years, respectively (P = 0.016). A control angio-computed tomography revealed an increased descending aorta diameter in 2 out of 14 late survivors. A positron emission tomography showed presence of arteritis in other vascular segments in 3 patients. Clinically isolated aortitis is extremely frequent in patients with inflammatory aortic disease. The diagnosis is often difficult and may be supported by routine pathologic evaluation of surgical explants and by multimodality imaging. The latter should be employed to allow adequate patient follow-up and to disclose potential recurrences in untreated aortic segments.

Diagnosis and differential diagnosis of large-vessel vasculitides

There are no universally accepted diagnostic criteria for large-vessel vasculitides (LVV), including giant cell arteritis (GCA) and Takayasu arteritis (TAK). Currently, available classification criteria cannot be used for the diagnosis of GCA and TAK. Early diagnosis of these two diseases is quite challenging in clinical practice and may be accomplished only by combining the patient symptoms, physical examination findings, blood test results, imaging findings, and biopsy results, if available. Awareness of red flags which lead the clinician to investigate TAK in a young patient with persistent systemic inflammation is helpful for the early diagnosis. It should be noted that clinical presentation may be highly variable in a subgroup of GCA patients with predominant large-vessel involvement (LVI) and without prominent cranial symptoms. Imaging modalities are especially helpful for the diagnosis of this subgroup. Differential diagnosis between older patients with TAK and this subgroup of GCA patients presenting with LVI may be difficult. Various pathologies may mimic LVV either by causing systemic inflammation and constitutional symptoms, or by causing lumen narrowing with or without aneurysm formation in the aorta and its branches. Differential diagnosis of aortitis is crucial. Infectious aortitis including mycotic aneurysms due to septicemia or endocarditis, as well as causes such as syphilis and mycobacterial infections should always be excluded. On the other hand, the presence of non-infectious aortitis is not unique for TAK and GCA. It should be noted that aortitis, other large-vessel involvement or both, may occasionally be seen in various other autoimmune pathologies including ANCA-positive vasculitides, Behçet's disease, ankylosing spondylitis, sarcoidosis, and Sjögren's syndrome. Besides, aortitis may be idiopathic and isolated. Atherosclerosis should always be considered in the differential diagnosis of LVV. Other pathologies which may mimic LVV include, but not limited to, congenital causes of aortic coarctation and middle aortic syndrome, immunoglobulin G4-related disease, and hereditary disorders of connective tissue such as Marfan syndrome and Ehler-Danlos syndrome.

Imaging modalities in the management of aortitis

Aortitis is a pathological term that refers to the inflammation of one or more layers of the aortic wall. It is associated with a wide spectrum of inflammatory diseases of infectious and non-infectious origins, and often present with vague clinical findings and non-specific laboratory results that can model other entities. As a result, aortitis may not form part of the initial workup and appropriate treatment can be delayed or missed. Therefore, imaging modalities are required to assess for inflammation and structural changes in the aorta to support or exclude the diagnosis of aortitis. This review presents current literature on the imaging modalities utilized in the diagnosis and management of aortitis, which surgeons and physicians should be familiar with for providing optimal patient care.

Aortitis as a Rare Cause of Aortic Aneurysm and Valve Regurgitation: Is Repair Precluded?

Aortitis is an infrequent cause of aortic root dilatation and aortic valve regurgitation. Valve-sparing procedures have been proposed, but there is not clear evidence of which is the treatment of choice. We report the case of a 38-year-old pregnant lady with a diagnosis of idiopathic aortitis associated with aortic root aneurysm and severe aortic valve regurgitation.