The red connection: a review of aortic and arterial fistulae with an emphasis on CT findings

Rare causes of acute non-variceal upper gastrointestinal bleeding: A comprehensive review

Non-variceal upper gastrointestinal bleeding (NVUGIB) is a common gastroenterological emergency associated with significant morbidity and mortality. Gastroenterologists and other involved clinicians are generally assisted by international guidelines in its management. However, NVUGIB due to peptic ulcer disease only is mainly addressed by current guidelines, with upper gastrointestinal endoscopy being recommended as the gold standard modality for both diagnosis and treatment. Conversely, the management of rare and extraordinary rare causes of NVUGIB is not covered by current guidelines. Given they are frequently life-threatening conditions, all the involved clinicians, that is emergency physicians, diagnostic and interventional radiologists, surgeons, in addition obviously to gastroenterologists, should be aware of and familiar with their management. Indeed, they typically require a prompt diagnosis and treatment, engaging a dedicated, patient-tailored, multidisciplinary team approach. The aim of our review was to extensively summarize the current evidence with regard to the management of rare and extraordinary rare causes of NVUGIB.

Secondary Aorto-Colonic Fistula: A Case Report and Literature Review of a Rare Complication after EVAR

Background: Aorto-enteric fistula (AEF) is a rare but fatal condition. The incidence of the overall AEF was approximately 0.36–2%, but the incidence of the aorto-colonic fistula was scarcely reported. A history of abdominal pain, fever, or gastrointestinal bleeding (GIB) in a patient with a history of aortic intervention should be highly suspected of this condition. This report describes a patient with lower GIB after an endovascular aneurysm repair (EVAR) for a symptomatic abdominal aortic aneurysm (AAA). Case Presentation: A 65-year-old man with a history of EVAR for symptomatic AAA presented with a massive lower GIB for two weeks. He also had a history of left lower quadrant pain and low-grade fever. Diverticular disease was suspected, and medical treatment was administered. After the initial conservative treatment, a colonoscopy was performed. The findings showed a fistula that exposed an aortic stent graft at the left-sided colon. An aorto-colonic fistula was diagnosed. After administering intravenous (IV) antibiotics, a staged axillo-bifemoral bypass graft with aortic stent graft explantation was performed. The patient recovered well and was discharged home after a month of hospitalization and IV antibiotics. Conclusion: In a patient with a history of aortic intervention, any abdominal pain, unknown fever, or even GIB should be suspected of complications of aortic intervention. Highly suspicious of this rare condition is the key to an early diagnosis and prompt treatment.

Aortic Fistulas: Pathophysiologic Features, Imaging Findings, and Diagnostic Pitfalls

Fistulas between the aorta and surrounding organs are extremely rare but can be fatal if they are not identified and treated promptly. Most of these fistulas are associated with a history of trauma or vascular intervention. However, spontaneous aortic fistulas (AoFs) can develop in patients with weakened vasculature, which can be due to advanced atherosclerotic disease, collagen-vascular disease, vasculitides, and/or hematogenous infections. The clinical features of AoFs are often nonspecific, with patients presenting with bleeding manifestations, back or abdominal pain, fever, and shock. Confirmation with invasive endoscopy is often impractical in the acute setting. Imaging plays an important role in the management of AoFs, and multiphasic multidetector CT angiography is the initial imaging examination of choice. Obvious signs of AoF include intravenous contrast material extravasation into the fistulizing hollow organ, tract visualization, and aortic graft migration into the adjacent structure. However, nonspecific indirect signs such as loss of fat planes and ectopic foci of gas are seen more commonly. These indirect signs can be confused with other entities such as infection and postoperative changes. Management may involve complex and staged surgical procedures, depending on the patient's clinical status, site of the fistula, presence of infection, and anticipated tissue friability. As endovascular interventions become more common, radiologists will need to have a high index of suspicion for this entity in patients who have a history of aneurysms, vascular repair, or trauma and present with bleeding. Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article. ^©RSNA, 2021.

Extraabdominal Rupture of an Inflammatory Abdominal Aortic Aneurysm in a Patient With Aortodecubital Fistula: A Case Report

Aortodecubital fistula is a pathologic communication between aorta and a decubitus ulcer. It is very rarely encountered vascular condition in abdominal aortic aneurysms (AAA), with difficult diagnostics and high mortality. Patients often present with systemic and local infection and are at risk for hemorrhage. We present a paraplegic patient with fistulous communication between an inflamed abdominal aortic aneurysm and a sacral decubitus ulcer, leading to intermittent bleeding episodes and finally to exsanguination. While extremely rare, this case emphasizes the need for early, accurate diagnosis and salvage intervention when possible.

Risk Factors for Mortality in Patients with Aortoesophageal Fistula Related to Aortic Lesions

Objective

Aortoesophageal fistula (AEF) related to aortic aneurysm and dissection is an uncommon but life-threatening condition. We performed a systematic review of risk factors for mortality and factors associated with the prognosis of AEF.

Methods

A systematic search of the PubMed, Embase, and Cochrane Library databases was performed. Clinical characteristics, diagnostic methods, and treatments were assessed in terms of their ability to predict mortality.

Results

The systematic review identified 184 eligible articles including 219 patients with AEF. Multivariable Cox regression revealed positive correlations of hemorrhagic shock (hazard ratio (HR): 1.824, 95% CI: 1.217-2.735, P = 0.004), sepsis (HR: 1.714, 95% CI: 1.112-2.641, P = 0.015), multiorgan failure (HR: 3.060, 95% CI: 1.470-6.368, P = 0.003), and conservative treatment (HR: 5.257, 95% CI: 3.405-8.116, P < 0.001) with mortality and a negative correlation between combination therapy (aortic graft replacement and esophagectomy) and mortality (HR: 0.319, 95% CI: 0.125-0.813, P = 0.017). Kaplan–Meier survival analysis showed that the 1-year cumulative survival rate was 42.5 ± 3.8%. The overall fistula-related mortality rate was 47.0% (103/219). The most common causes of death were bleeding (54.9%) and infection (29.2%).

Conclusions

We found that hemorrhagic shock, sepsis, and multiorgan failure were risk factors for death in patients with AEF. Additionally, conservative treatment was associated with a higher rate of mortality, while combined aortic graft replacement and esophagectomy improved the prognosis.

Ileal artery pseudoaneurysm: a rare cause of gastrointestinal bleed

Aorto-enteric fistulas are life-threatening conditions that occur commonly between the aorta and duodenum. Our case describes a fistula between the ileal artery and small bowel. To our knowledge, ileal artery fistulas are more commonly described in surgical cases, unlike our case. This case emphasizes early diagnosis of an aorto-enteric fistula causing life-threatening gastrointestinal bleeding to improve morbidity and survival.

Primary and secondary arterial fistulas during chronic Q fever

OBJECTIVE

After primary infection with Coxiella burnetii, patients may develop acute Q fever, which is a relatively mild disease. A small proportion of patients (1%-5%) develop chronic Q fever, which is accompanied by high mortality and can be manifested as infected arterial or aortic aneurysms or infected vascular prostheses. The disease can be complicated by arterial fistulas, which are often fatal if they are left untreated. We aimed to assess the cumulative incidence of arterial fistulas and mortality in patients with proven chronic Q fever.

METHODS

In a retrospective, observational study, the cumulative incidence of arterial fistulas (aortoenteric, aortobronchial, aortovenous, or arteriocutaneous) in patients with proven chronic Q fever (according to the Dutch Chronic Q Fever Consensus Group criteria) was assessed. Proven chronic Q fever with a vascular focus of infection was defined as a confirmed mycotic aneurysm or infected prosthesis on imaging studies or positive result of serum polymerase chain reaction for C. burnetii in the presence of an arterial aneurysm or vascular prosthesis.

RESULTS

Of 253 patients with proven chronic Q fever, 169 patients (67%) were diagnosed with a vascular focus of infection (42 of whom had a combined vascular focus and endocarditis). In total, 26 arterial fistulas were diagnosed in 25 patients (15% of patients with a vascular focus): aortoenteric (15), aortobronchial (2), aortocaval (4), and arteriocutaneous (5) fistulas (1 patient presented with both an aortocaval and an arteriocutaneous fistula). Chronic Q fever-related mortality was 60% for patients with and 21% for patients without arterial fistula (P < .0001). Primary fistulas accounted for 42% and secondary fistulas for 58%. Of patients who underwent surgical intervention for chronic Q fever-related fistula (n = 17), nine died of chronic Q fever-related causes (53%). Of patients who did not undergo any surgical intervention (n = 8), six died of chronic Q fever-related causes (75%).

CONCLUSIONS

The proportion of patients with proven chronic Q fever developing primary or secondary arterial fistulas is high; 15% of patients with a vascular focus of infection develop an arterial fistula. This observation suggests that C. burnetii, the causative agent of Q fever, plays a role in the development of fistulas in these patients. Chronic Q fever-related mortality in patients with arterial fistula is very high, in both patients who undergo surgical intervention and patients who do not.