Multimodality Imaging Approach towards Primary Aortic Sarcomas Arising after Endovascular Abdominal Aortic Aneurysm Repair: Case Series Report

Primary aortic neoplasms are rare. Aortic sarcoma arising after endovascular aneurysm repair (EVAR) is a scarce subset of primary aortic malignancies, reports of which are infrequent in the published literature. The diagnosis of aortic sarcoma is challenging due to its non-specific clinical presentation, and the prognosis is poor due to delayed diagnosis, rapid proliferation, and propensity for metastasis. Post-EVAR, aortic sarcomas may mimic other more common aortic processes on surveillance imaging. Radiologists are rarely knowledgeable about this rare entity for which multimodality imaging and awareness are invaluable in early diagnosis. A series of three pathologically confirmed cases are presented to display the multimodality imaging features and clinical presentations of aortic sarcoma arising after EVAR.     

Chest radiography in acute aortic syndrome: pearls and pitfalls

Acute aortic syndrome is a group of life-threatening diseases of the thoracic aorta that usually present to the emergency department. It includes aortic dissection, aortic intramural hematoma, and penetrating aortic ulcer. Rare aortic pathologies of aorto-esophageal fistula and mycotic aneurysm may also be included in this list. All these conditions require urgent treatment with complex clinical care and management. Most patients who present with chest pain are evaluated with a chest radiograph in the emergency department. It is important that maximum diagnostic information is extracted from the chest radiograph as certain signs on the chest radiograph are extremely useful in pointing towards the diagnosis of acute aortic syndrome.     

Aortic valve stenosis: CT contributions to diagnosis and therapy

As populations in Western civilizations are aging, the prevalence of degenerative aortic valve stenosis is increasing. CT imaging provides information on aortic valve pathology in many ways: In nonenhanced scans, aortic valve calcification can be quantified accurately, which helps to understand the pathogenesis and progression of aortic sclerosis and stenosis. After contrast injection, CT allows excellent visualization of aortic valve structure and, through measurement of the aortic valve area, is capable to serve as a "backup method" for the assessment of aortic valve stenosis, especially if other imaging methods are difficult to interpret. Importantly, CT tends to overestimate aortic valve opening areas in comparison to transthoracic echocardiography, which relies on the continuity equation for quantifying aortic stenosis, based on flow velocities and the estimated area of the left ventricular outflow tract. It has recently been shown that the oval rather than round shape of the left ventricular outflow tract is the most likely factor behind this systematic difference between functional compared with anatomic assessment of aortic valve stenosis. In fact, the ability to provide superbly accurate anatomic imaging of the aortic valve and entire aortic root makes CT a uniquely useful tool for the planning of transcatheter aortic valve implantation. Hence, CT imaging spans a wide range of applications in aortic valve disease, from basic research to diagnosis and treatment planning. This review aims to summarize the current state of the art concerning imaging of the aortic valve by CT and the potential clinical applications.     

Useful CT findings for predicting the progression of aortic intramural hematoma to overt aortic dissection

PURPOSE: The purpose of this work was to assess useful CT findings for predicting the progression of aortic intramural hematoma to aortic dissection. METHOD: We analyzed the CT findings of 29 patients with aortic intramural hematoma with regard to the following: involved site, maximum thickness of hematoma, presence or absence of compression of true lumen, and pericardial and pleural effusion. CT findings were compared with those of the patients who progressed to aortic dissection (Group I) and those who did not (Group II). Each CT finding was evaluated with independent t test and Mann-Whitney U test (p < 0.05). RESULTS: Seven of 8 cases of Type A aortic intramural hematoma and 3 of 21 cases of Type B aortic intramural hematoma progressed to aortic dissection. The type of aortic intramural hematoma, maximum thickness of hematoma, compression of true lumen, and pericardial or pleural effusion were significantly different in Groups I and II. CONCLUSION: Type A aortic intramural hematoma, maximum thickness of hematoma, compression of true lumen, and pericardial or pleural effusion are the useful CT findings for predicting the progression of aortic intramural hematoma to aortic dissection.     

Mirror-image right aortic arch: A proposed mechanism in symptomatic vascular ring

We describe a rare case of right aortic arch with mirror-image branching and a left ductus arteriosus that form an anomalous vascular ring. The unusual feature of this symptomatic vascular ring is presence of a left (posterior) circumflex descending aorta in lieu of an aortic diverticulum which usually represents the posterior element of the vascular ring associated with right aortic arch and mirror-image branching. This we believe is the seventh reported case of Type 1 right aortic arch and only the third such case with a left circumflex descending aorta. Accurate diagnosis was made by barium esophagogram and angiocardiogram and was confirmed surgically. We propose a new theory as to why some vascular rings formed by the right aortic arch are symptomatic while others are not.     

Blunt traumatic injury of the ascending aorta: multidetector CT findings in two cases

Blunt ascending aortic injuries are rare in clinical practice. We have encountered two types of injuries to the ascending aorta with multidetector computed tomography: (1) a tear of the wall of the aortic root with a contained rupture and associated hemopericardium and (2) a tear at the level of the aortic valve cusp without associated hemopericardium. In reviewing our experience with aortic trauma at our institution under IRB waiver of consent, we encountered two cases of ascending aortic rupture that illustrate the two injury patterns. We present these two cases to alert radiologists to the multidetector computed tomographic findings of this life-threatening injury.     

Stent-graft treatment of thoracoabdominal aortic aneurysms after complete visceral debranching

Complex thoracoabdominal aortic aneurysm repair remains a difficult problem from both open and endoluminal approaches. The reduced morbidity and mortality rates reported to be associated with aortic stent-graft procedures makes this option more attractive, but it is hampered by the need for adequate proximal and distal seal zones. While branched and fenestrated aortic stent-grafts are being refined, an alternative is a two-stage surgical and endoluminal approach that is particularly useful for aneurysms involving the aortic visceral segment. The present report describes stent-graft repair in two patients after complete visceral artery revascularization or "debranching."     

Aortic arch aneurysms: treatment with extraanatomical bypass and endovascular stent-grafting

Endovascular repair of thoracic aortic aneurysms is emerging as an attractive alternative to surgical graft replacement. However, patients with aortic arch aneurysms are often excluded from the target of endovascular repair because of lack of suitable landing zones, especially at the proximal ones. In this paper we describe our method for treating patients with aortic arch aneurysms using a combination of extraanatomical bypass surgery and endovascular stent-grafting.     

Aortic dissection manifested as leg ischemia

The ischemic leg as the only clinical manifestation of an aortic dissection is rare. Without the usual symptoms of an aortic dissection, this diagnosis may easily by overlooked during routine peripheral angiography for the ischemic limb. Three cases are reviewed in which the patient was thought to have a spontaneous peripheral vascular occlusion, but was later found to have an aortic dissection without the usual thoracic or abdominal symptoms. The radiologist should observe carefully for signs of dissection such as fusiform narrowing of a vessel, nonfilling of branches of the aorta, or displacement of the intima into aortic lumen.     

Investigations of fatal causes of chest pain: case report and literature review

A case of fatal ascending aortic dissection (AAD) misdiagnosed as pulmonary embolism (PE) despite strong radiological evidence is described. The occurrence of this serious pathology is uncommon. Its prompt diagnosis and treatment are crucial. Anticoagulant therapy for pulmonary embolism should be withheld until acute aortic dissection is excluded definitively. A management approach to optimise the outcome of patients with chest pain in which ascending aortic dissection and/or pulmonary embolism are suspected is presented.     

Unusual Congenital Aortic Anomaly with Rare Common Celiamesenteric Trunk Variation: MR Angiography and Digital Substraction Angiography Findings

Magnetic resonance angiography and digital substraction angiography (DSA) findings in a case with a rare congenital thoracoabdominal aortic hypoplasia and common celiamesenteric trunk variation with occlusion of infrarenal abdominal aorta are described here. To our knowledge, this aortic anomaly has not been previously described in the English literature. DSA is the optimum imaging modality for determination of aortic hypoplasia, associated vascular malformations, collateral vessels, and direction of flow within vessels.     

The role of gadolinium-enhanced MR imaging in the preoperative evaluation of inflammatory abdominal aortic aneurysm

Inflammatory abdominal aortic aneurysm is an uncommon variant of abdominal aortic aneurysms. Thorough preoperative imaging of the extent of the aneurysm and inflammation and the associated complications are crucial in the management of this condition. We report a case of inflammatory abdominal aortic aneurysm where, after the initial contrast-enhanced CT, gadolinium-enhanced MR imaging was used to define the true extent of the inflammation and differentiate inflammation from mural thrombus at the iliac extension of the aneurysm. The imaging appearances are presented and the impact of MR imaging on further surgical management options including endovascular repair are discussed.     

Spiral CT aortography: an efficient technique for the diagnosis of traumatic aortic injury

The objective of this study was to assess the efficiency of spiral CT (SCT) aortography for diagnosing acute aortic lesions in blunt thoracic trauma patients. Between October 1992 and June 1997, 487 SCT scans of the chest were performed on blunt thoracic trauma patients. To assess aortic injury, the following SCT criteria were considered: hemomediastinum, peri-aortic hematoma, irregular aspect of the aortic wall, aortic pseudodiverticulum, intimal flap and traumatic dissection. Aortic injury was diagnosed on 14 SCT examinations (2.9 %), five of the patients having had an additional digital aortography that confirmed the aortic trauma. Twelve subjects underwent surgical repair of the thoracic aorta, which in all but one case confirmed the aortic injury. Two patients died before surgery from severe brain lesions. The aortic blunt lesions were confirmed at autopsy. According to the follow-up of the other 473 patients, we are aware of no false-negative SCT examination. Our limited series shows a sensitivity of 100 % and specificity of 99.8 % of SCT aortography in the diagnosis of aortic injury. It is concluded that SCT aortagraphy is an accurate diagnostic method for the assessment of aortic injury in blunt thoracic trauma patients. Received 18 July 1997; Revision received 11 September 1997; Accepted 23 October 1997     

Supracristal ventricular septal defects: spectrum of associated lesions and complications.

The clinical records and radiographs of 46 patients with a supracristal ventricular septal defect are reviewed to illustrate the spectrum of associated lesions and complications seen with this defect. The presence of a supracristal ventricular septal defect compromises the normal conal muscular support of the aortic valve, usually in the region of the right sinus of Valsalva, and, consequently, complications involving the aortic valve are frequently noted. Decreased sinus support may lead progressively to prolapse of the right aortic cusp through the supracristal ventricular septal defect into the right ventricular infundibulum effecting sequentially aortic regurgitation, right ventricular outflow obstruction, and ultimately right sinus of Valsalva-right ventricular fistula. This potential progression is an indication for early recognition and repair of the supracristal ventricular septal defect. A supracristal ventricular septal defect is also an integral component of the Taussig-Bing malformation, is present in the majority of patients with aortic arch interruption, and may be seen in as many as 25% of Oriental patients with tetralogy of Fallot.     

The spontaneous regression of a dissection of the descending aorta

The outcome of an aortic dissection is either endothelialisation of the false lumen forming a so-called double aorta, or thrombosis of the sack leading to fibrosis. Healing of an aortic dissection, particularly if thrombosis and organisation have obliterated the dissected segment, is rare and there are only a few case reports on this finding. We report on a case where spontaneous resolution of the false lumen of Type B aortic dissection was demonstrated by serial contrast enhanced computed tomography after antihypertensive medical treatment.     

Complete interruption of aortic arch diagnosed in adulthood: a case report

Few patients with interrupted aortas survive into maturity, and the majority of instances are diagnosed in young children. There are only a few cases of this extremely rare total aortic interruption that survives into maturity, necessitating the substantial growth of collaterals to supply the descending aorta. Here, we describe a rare instance of an interrupted aorta in a 43-year male that presented in late adulthood with complete interruption of the aortic arch. The patient has remained symptom-free and without treatment. This case gives us an idea about how one can survive into adulthood with complete interruption of the aortic arch given that extensive collaterals are formed.     

MDCT of ductus diverticulum: 3D cinematic rendering to enhance understanding of anatomic configuration and avoid misinterpretation as traumatic aortic injury

Acute aortic injuries are not common in the setting of severe blunt trauma, but lead to significant morbidity and mortality. High-quality MDCT with 2D MPRs and 3D rendering are essential to identify aortic trauma and distinguish anatomic variants and other forms of aortic pathology from an acute injury. Misinterpretation of mimics of acute aortic injury can lead to unnecessary arteriography and thoracic surgery. Since most traumatic injuries occur in the distal arch, radiologists must be cognizant of the range of appearances of variants related to the ductus diverticulum. Cinematic rendering (CR) is a new 3D post-processing tool that provides even greater anatomic detail than traditional volume rendering. In this case series, CR is used to impart to radiologists a better understanding of various anatomic configurations that can be seen with a ductus diverticulum.     

多层螺旋CT血管造影在主动脉瘤腔内带膜内支架置入术后并发症诊断中的应用

目的：探讨多层螺旋CT血管造影（CTA）在主动脉瘤腔内带膜内支架置入术后并发症诊断中的应用。方法：31例腹主动脉瘤和主动脉夹层腔内带膜内支架置入术后行多层螺旋CT血管造影，采用准直2.5mm，层厚3.0mm，螺矩6-8，重建方法为容积显示（VR）、表面遮盖显示（SSD）、最大密度投影法（MIP）及多层面重建法（MPR）。观察图像确定有无术后并发症，并比较4种重建方法对并发症的显示情况。结果：31例中有1例术后内支架出现局限性断裂，VR、MIP及MPR均清晰显示了内支架的变化，SSD未能显示。1例内支架展开不良，4种重建方法均明确显示；5例术后出现渗漏，VR及MPR清晰显示渗漏的部位、形态及内漏量，MIP、SSD仅显示其中的4例。在显示支架内血流情况及瘤周血栓方面，VR及MPR能明确支架内有无血栓形成及腔内带膜内支架置入术后的转归变化，VR及MPR显示1例术后支架内血栓形成，SSD及MIP未能显示。结论：多层螺旋CTA有利于主动脉瘤腔内带膜内支架置考试术后并发症的诊断；VR及MPR图像优于SSD及MIP，能为术后内支架情况作出更准确的判断 。     

Utility of 4D Flow MRI in Thoracic Aortic Diseases: A Literature Review of Clinical Applications and Current Evidence

Despite the recent technical developments, surgery on the thoracic aorta remains challenging and is associated with significant mortality and morbidity. Decisions about when and if to operate are based on a balance between surgical risk and the hazard of aortic rupture. These decisions are sometimes difficult in elective cases of thoracic aortic diseases, including aneurysms and dissections. Abnormal wall stress derived from flow alterations influences disease progression. Therefore, a better understanding of the complex hemodynamic environment inside the aortic lumen will facilitate patient-specific risk assessments of complications, which enable clinicians to provide timely prophylactic interventions. Time-resolved 3D phase-contrast (4D flow) MRI has many advantages for the in vivo assessment of flow dynamics. Recent developments in 4D flow imaging techniques has led to significant advances in our understanding of physiological flow dynamics in healthy subjects and patients with thoracic aortic diseases. In this clinically focused review of thoracic aortic diseases, we demonstrate the clinical advances acquired with 4D flow MRI from published studies. We provide a systematic overview of key evidences and considerations regarding normal thoracic aortas, thoracic aortic aneurysms, aortic dissections, and thoracic aortas with prosthetic graft replacement.     

Carotid duplex sonography: bisferious pulse contour in patients with aortic valvular disease.

Characteristic systolic and diastolic pulse contours occur in the carotid Doppler waveforms of patients with aortic valvular disease that have not previously been described in publications concerning carotid duplex sonography. The purpose of this study was to evaluate the presence and characterize the nature of these carotid duplex waveform abnormalities in patients with known aortic valve disease and to correlate these changes with the severity of valve dysfunction. The study group consisted of 26 patients with aortic regurgitation or combined aortic regurgitation and aortic stenosis. Duplex studies were retrospectively reviewed by two radiologists for the presence of two systolic peaks, and for the presence of diastolic reversal of flow direction. This pattern of two systolic peaks, characteristic of aortic regurgitation, is called bisferious from the Latin "twice beating." Aortic regurgitation was graded by echocardiography as mild, moderate, or severe by the cardiologists reviewing the examination. A group of 20 age-matched patients without aortic valvular disease were similarly assessed. The bisferious pattern was demonstrated in 13 (50%) of 26 patients. Five (19%) of 26 patients had significant reversal of diastolic flow. Four patients were studied both before and after aortic valve replacement. Three had bisferious wave contours preoperatively; two of these also had diastolic reversal of flow. The fourth patient had retrograde flow in diastole without systolic contour abnormality. Postoperatively, all carotid waveforms were normal. None of the duplex waveforms in the control group demonstrated characteristic systolic or diastolic abnormalities. The bisferious waveform and retrograde diastolic flow are Doppler patterns associated with aortic valvular disease. These patterns are reversible after aortic valve replacement. While echocardiography remains the study of choice in the evaluation of suspected valvular dysfunction, up to one third of patients with aortic regurgitation may not have a detectable murmur. Therefore, identifying these patterns on carotid duplex examinations may provide clinically useful information and serve as a clue to previously unsuspected cardiovascular disease.