A ruptured mycotic aortic aneurysm in a patient with urinary retention: A case report

Symptomatic abdominal aortic aneurysm (AAA) is a diagnosis that is a true emergency. Since AAAs are typically asymptomatic prior to rupturing, they can easily be missed. When an abdominal aortic aneurysm becomes symptomatic and ruptures, the ramifications can be catastrophic for the patient. We present a case of a 55-year-old male who presented with urinary retention and suprapubic pain. Computerized tomography demonstrated a rapidly expanding AAA and signs of impending rupture. Emergent vascular surgical repair was performed successfully. There was concern for mycotic nature of the AAA with recent COVID-19 infection and possible bacteremia. This case demonstrates the need for maintaining a wider differential when examining patients and avoiding anchoring bias and serves as a point of discussion for potential complications of COVID-19 infection.     

Endoluminal Treatment of Ruptured Abdominal Aortic Aneurysm with Small Intestinal Submucosa Sandwich Endografts: A Pilot Study in Sheep

Purpose: To evaluate efficacy of small intestinal submucosa (SIS) Sandwich endografts for the treatment of acute rupture of abdominal aortic aneurysms (AAA) and to explore the short-term reaction of the aorta to this material. Methods: In eight adult sheep, an infrarenal AAA was created transluminally by dilation of a short Palmaz stent. In six sheep, the aneurysm was then ruptured by overdilation of the stent with a large angioplasty balloon. Two sheep with AAAs that were not ruptured served as controls. A SIS Sandwich endograft, consisting of a Z stent frame with 5 bodies and covered inside and out with SIS, was used to exclude the ruptured and non-ruptured AAAs. Follow-up aortography was done immediately after the procedure and before sacrifice at 4, 8, or 12 weeks. Autopsy and histologic studies followed. Results: Endograft placement was successful in all eight sheep. Both ruptured and non-ruptured AAAs were successfully excluded. Three animals with AAA rupture developed hind leg paralysis due to compromise of the arterial supply to the lower spinal cord and were sacrificed 1 day after the procedure. In five animals, three with rupture and two controls, follow-up aortograms revealed no aortic stenoses and no perigraft leaks. Gross and histologic studies revealed incorporation of the endografts into the aortic wall with replacement of SIS by dense neointima that was completely endothelialized in areas where the endograft was in direct contact with the aortic wall. In central portions of the endograft, in contact with the thrombosed aneurysm, endothelialization was incomplete even at 12 weeks. Conclusion: The SIS Sandwich endografts effectively excluded simple AAAs and ruptured AAAs. They were rapidly incorporated into the aortic wall. A detailed long-term study is warranted.     

Spared flow tract within the mural thrombus of an aortic aneurysm: its pathogenesis and clinical importance

The purpose of this case report is to determine the unique pathogenesis of a "spared flow tract" through a thick mural thrombus of an aortic aneurysm mimicking the penetrating or dissecting tract of an impending or acute rupture of an abdominal aortic aneurysm (AAA) and to discuss its clinical importance. Three blood flow tracts (i.e., spared flow tracts) penetrating to aortic major branches (inferior mesenteric arteries in two and left renal artery in one) through thick mural thrombi of three aortic aneurysms were found on thin section spiral CT scans. Histopathological examination revealed that the tracts were formed by thrombi and partially covered with endothelial cells. In conclusion, spared flow tracts may be pathways continuing to the aortic major branches through thick mural thrombi of aortic aneurysms and are spared from thrombogenesis because of relatively high blood flows. Their pathogenesis is definitely different from penetrating or dissecting tracts within mural thrombi of ruptured AAAs. Spared flow tracts should not be misinterpreted as penetrating or dissecting tracts of impending or acute rupture.     

Renewed endovascular repair for recurrent acute abdominal aortic aneurysm

The aim of the study was to describe the successful endovascular management of a patient who was admitted urgently with a second episode of acute abdominal aortic aneurysm (AAA) 30 months after emergency endovascular abdominal aortic aneurysm repair (eEVAR) for a ruptured AAA. The patient, an 84 year-old male physician, presented with severe acute abdominal and back pain. Contrast-enhanced computer tomography scanning showed type III endoleak owing to complete disconnection of both graft limbs and the prosthetic main body. Treatment consisted of acute stent-grafting with two bridging stent-grafts to seal the endoleak and reline the graft. The patient is alive and well 6 months postoperatively. This case indicates the need for follow-up after eEVAR, but also that complications can be managed endovascularly.     

MSCT在腹主动脉瘤临床诊疗中的价值

目的：评估 MSCT在腹主动脉瘤(AAA)诊断和预后评价的价值。方法前瞻性收集本院经 MSCT 检查的26例疑似AAA患者,分析 MSCT检查的准确性和特点。结果26例患者经 MSCT诊断为 AAA,其中17例真性 AAA,9例假性 AAA。真性AAA的MSCT显示腹主动脉呈梭形扩张并向左前方膨出,瘤破裂患者残余瘤腔周围可见血栓和瘤壁钙化;假性AAA的MSCT显示腹主动脉旁偏心的膨大肿块,肿块可在血管钙化边界之外。手术诊断结果为25例 AAA,MSCT 与手术病理结果的符合率为96.1%(25/26);本组患者均出现动脉壁钙化的现象,其中17例伴有附壁血栓。结论 MSCT是一种安全、有效和无创性的诊断技术,对于AAA的早期发现,病情判断和指导治疗有较高的临床应用价值。     

Endovascular repair of ruptured abdominal aortic aneurysm: feasibility and impact on early outcome

PURPOSE: Open repair of ruptured abdominal aortic aneurysms (AAAs) still has a high associated mortality rate. The impact of the introduction of endovascular treatment on the early outcomes of ruptured AAAs was examined at a single institution. The suitability of acute endovascular aneurysm repair (EVAR) in patients with ruptured AAAs was also assessed. MATERIALS AND METHODS: Retrospective review was conducted in 39 consecutive patients treated for ruptured AAA from 2001 to 2004. The patients were divided into 15 who underwent open repair from 2001 to 2002 (group I) and 24 who were treated with open repair (n=13; 54%) or endovascular repair (n=11; 46%) from 2003 to 2004 (group II). Hospital charts and computed tomographic scans were reviewed to evaluate the feasibility of EVAR. RESULTS: Age, sex, and aneurysm size were similar between the two groups. The 30-day mortality rates were 53% in group I and 8% in group II (P=.003). Median procedure times were shorter in the patients who underwent EVAR. Intensive care unit stay and hospital stay were 22.0 days+/-29.6 and 29.7 days+/-33.8, respectively, in group I, and 5.6 days+/-4.4 and 16.1 days+/-10.9, respectively, in group II (P<.03). Eleven patients were found ineligible for EVAR as a result of an unsuitable neck (n=5) or iliac arteries (n=3) or both (n=3). No graft failure was detected during follow-up. CONCLUSIONS: After introduction of acute EVAR, a total of 46% of patients with ruptured AAAs were treated with the procedure. Potentially, 54% of patients could have been suitable for EVAR. Endovascular stent-graft implantation has significantly improved outcomes in ruptured AAAs and may therefore be beneficial in the overall treatment strategy in these patients.     

3D segmentation of abdominal aorta from CT-scan and MR images

We designed a generic method for segmenting the aneurismal sac of an abdominal aortic aneurysm (AAA) both from multi-slice MR and CT-scan examinations. It is a semi-automatic method requiring little human intervention and based on graph cut theory to segment the lumen interface and the aortic wall of AAAs. Our segmentation method works independently on MRI and CT-scan volumes and has been tested on a 44 patient dataset and 10 synthetic images. Segmentation and maximum diameter estimation were compared to manual tracing from 4 experts. An inter-observer study was performed in order to measure the variability range of a human observer. Based on three metrics (the maximum aortic diameter, the volume overlap and the Hausdorff distance) the variability of the results obtained by our method is shown to be similar to that of a human operator, both for the lumen interface and the aortic wall. As will be shown, the average distance obtained with our method is less than one standard deviation away from each expert, both for healthy subjects and for patients with AAA. Our semi-automatic method provides reliable contours of the abdominal aorta from CT-scan or MRI, allowing rapid and reproducible evaluations of AAA.     

Use of the Endurant Stent Graft System for Ruptured Infrarenal Aortic Aneurysms: Short-term Experience in Nine Patients

PurposeTo report the early results of use of the Endurant stent graft in the treatment of ruptured abdominal aortic aneurysms (AAAs).Materials and MethodsNine consecutive patients (seven men and two women; mean age, 76 y; range, 65–87 y) underwent endovascular aneurysm repair (EVAR) for a ruptured AAA with the Endurant stent graft between April and December 2012. EVAR was emergent in all cases. Early technical success, clinical success, major complication, and mortality rates were analyzed.ResultsIntraoperative immediate technical success was achieved in all nine patients. The 30-day clinical success rate was 67% (six of nine patients). The 30-day mortality rate was 33% (three of nine patients). During a mean follow-up of 6 months (range, 3–10 mo), none of the cases required reintervention; there was one late death attributed to probable endograft infection.ConclusionsThe short-term results of EVAR with the Endurant stent graft in patients with ruptured AAAs are encouraging.     

Elevated plasma levels of matrix metalloproteinase-9 in patients with abdominal aortic aneurysms: a circulating marker of degenerative aneurysm disease

PURPOSE: Matrix metalloproteinase-9 (MMP-9) is abundantly expressed in abdominal aortic aneurysms (AAAs), where it plays a pivotal role in connective tissue destruction. Elevated plasma concentrations of MMP-9 (MMP-9PL) also have been reported in patients with AAAs, but it is unclear if this can distinguish patients with AAAs from those with atherosclerotic occlusive disease (AOD). The purpose of this study was to further define the utility of elevated MMP-9PL levels in the diagnosis and evaluation of AAAs, and to examine if changes in MMP-9PL can be used as a functional biomarker of degenerative aneurysm disease. MATERIALS AND METHODS: Peripheral venous blood was obtained from 25 patients with AAAs, 15 patients with AOD, and five normal control subjects. MMP-9PL levels were determined by an enzyme-linked immunosorbent assay. In four patients undergoing open AAA repair, MMP-9PL levels were directly compared with the amount of MMP-9 produced in aortic tissue. Six additional patients undergoing operative AAA repair were followed for 3-10 months to determine how treatment affected elevated MMP-9PL concentrations. RESULTS: Mean (+/- SE) MMP-9PL was 36.1 +/- 7.7 ng/mL in normal control subjects, 54.7 +/- 10.5 ng/mL in patients with AOD, and 99.4 +/- 17.4 ng/mL in patients with AAAs (P < .05 versus normal control subjects and patients with AOD). Elevated MMP-9PL levels (> 87.8 ng/mL) were found in 12 of 25 (48%) patients with AAA but in only one of 15 (7%) patients with AOD (P < .05). MMP-9PL levels did not correlate significantly with either age, gender, or aneurysm diameter, although there was a trend toward the highest values in male patients with large AAAs. Production of MMP-9 in aneurysm tissues paralleled MMP-9PL levels, and elevated MMP-9PL levels decreased by 92.7% +/- 3.2% after surgical AAA repair. CONCLUSIONS: Elevated MMP-9PL levels were observed in approximately one half of patients with AAAs and less than 10% of those with AOD (positive predictive value of 92.3%), but normal MMP-9PL levels had limited utility in excluding the presence of an aortic aneurysm (negative predictive value, 52%). MMP-9PL levels in patients with AAAs appeared to directly reflect the amount of MMP-9 produced within aneurysm tissue, and MMP-9PL levels decreased substantially after aneurysm repair. Measures of circulating MMP-9 may provide a biologically relevant marker of connective tissue metabolism in patients with AAAs.     

Contrast-Enhanced Ultrasound in Detection and Follow-Up of an Infrarenal Abdominal Aortic Aneurysm with Aorto-Caval Fistula and Endovascular Treatment

An aorto-caval fistula is a rare complication of a symptomatic or ruptured infrarenal aortic aneurysm having a frequency of 3–6%. Patients typically present with clinical signs of diffuse abdominal pain associated with increasing venous congestion and tachycardia, rapid cardiopulmonary decompensation with acute dyspnea, and an audible machinerylike bruit. Perioperative mortality is high, ranging from 20% to 60%. We report a case of an endovascular aortic repair in a patient with a symptomatic infrarenal aortic aneurysm and an aorto-caval fistula. Contrast-enhanced ultrasound seems to be a promising new diagnostic option for the diagnosis and preoperative treatment planning for patients with abdominal aortic aneurysms with rupture into the inferior vena cava. It is in addition to computed tomography angiography. It might allow a more rapid and noninvasive diagnosis, especially for patients in intensive care because of its bedside availability. Because the examination is dynamic, additional information about blood flow between the aorta and inferior cava vein can be evaluated.     

An autopsy case of unexpected sudden death due to rupture of a thoracic aortic aneurysm into the left lung

Ruptured aortic aneurysms present with various signs and symptoms depending on the site of rupture and bleeding, often causing sudden death; however, rupture into the lung with hemoptysis and blood aspiration is very rare. We report a case of unexpected sudden death due to blood aspiration from rupture of a thoracic aortic aneurysm into the lung. An 83 year old man, who had a past history of surgery for an abdominal aortic aneurysm about 17 years previously, was found dead on his bed with massive hemoptysis. Medico-legal autopsy revealed rupture of a thoracic aortic aneurysm into the left lung, causing massive blood aspiration. Tight, diffuse pleural adhesion and the vulnerable wall of an aortic aneurysm due to advanced atherosclerosis with active inflammation appeared to have predominantly contributed to the penetration of the ruptured aneurysm into the lung. This case suggests that long-term clinical follow-up and management are needed for a patient with aortic aneurysm, and that a ruptured aortic aneurysm should be taken into consideration to identify the source of bleeding for hemoptysis.     

两例表现为急腹症的腹主动脉夹层动脉瘤破裂早期诊断

目的总结腹主动脉夹层动脉瘤破裂早期诊断体会。方法回顾分析2例腹主动脉夹层动脉瘤破裂的临床资料。结果2例曾被误诊为急性阑尾炎和急性胰腺炎,分别在就诊后6 h和80 h经急诊CT和超声检查得到确诊。结论腹主动脉夹层动脉瘤破裂临床表现复杂多样,早期诊断困难,易于漏诊误诊;对出现突发的、剧烈的、顽固的、一般治疗不能缓解的、症状与体征不符的、排除其他急腹症（如急性肠绞窄、重症胰腺炎、急性阑尾炎等）的腹胀腹痛,要想到腹主动脉夹层动脉瘤破裂的可能,结合急诊CT和超声检查可确诊,必要时要复查腹部CT。     

Translumbar repair of a type II endoleak associated with an aorta-to-left renal vein fistula after aortic stent-graft placement

An abdominal aortic aneurysm (AAA) is a serious medical condition with significant associated morbidity and mortality. Endograft repair of AAAs is a therapy in evolution, but offers promise as a minimally invasive treatment option. Persistent sac pressurization via endoleaks has limited wider application of stent-grafting technology. The present report describes a case of an AAA with rupture into a retroaortic left renal vein that was treated acutely with aortic stent-graft repair. Continued aneurysm enlargement and a large type II endoleak drained by an arteriovenous fistula were subsequently treated via a translumbar approach.     

Posterior "Nutcracker" phenomenon in a patient with abdominal aortic aneurysm

We report on a posterior "nutcracker" phenomenon due to an abdominal aortic aneurysm in a patient with a retro-aortic left renal vein. A 71-year-old man with a known abdominal aortic aneurysm presented in the emergency room with mild hematuria and flank pain. Computed tomography angiography revealed an aortic aneurysm, which compressed the left renal vein between the aorta and the vertebral column. Compression of the left renal vein, due to the aorta with consecutive congestion and hematuria as well as flank pain, was previously described as nutcracker phenomenon. In case of a retro-aortic left renal vein, increase of the aortic diameter can lead to compression of the renal vein and furthermore to the classical signs and symptoms of the "nutcracker" phenomenon, even though the aneurysm is not ruptured or there are no aorto-caval or aorto-left renal vein fistulas.     

A Technique of “Chimney Nellix” for the Management of Type 1a Endoleak After EVAR

This report presents 3 procedures with visceral “chimney stenting” in conjunction with an endovascular aneurysm sealing (EVAS) device, known as chEVAS, for treatment of type 1a endoleak. It includes the first published chEVAS in a patient with previous fenestrated endovascular aneurysm repair (FEVAR). Cases include an 80-year-old man 8 years after FEVAR for a juxtarenal abdominal aortic aneurysm (AAA); an 85-year-old woman 9 months after endovascular aneurysm repair (EVAR) for a ruptured infrarenal AAA; and an 84-year-old woman 3 months after EVAR for a symptomatic infrarenal AAA. Technical success was achieved in all cases, with 1 postoperative death. The remaining 2 patients had no residual type 1a endoleak at 10 and 14 months respectively.     

To see or not to see – Ambiguous findings on post-mortem cross-sectional imaging in a case of ruptured abdominal aortic aneurysm

We present a case of a ruptured abdominal aortic aneurysm (AAA) with ambiguous accessory findings on post-mortem computed-tomography (PMCT), post-mortem magnetic resonance (PMMR) imaging, and PMCT-angiography (PMCTA) suggestive of thoracic aortic dissection. The diagnosis of ruptured AAA was confirmed by autopsy; however, there was no aortic dissection. The imaging findings that mimicked the presence of aortic dissection might have been an atypical presentation of post-mortem clotting or sedimentation. This case is an ideal example to illustrate benefits, limitations, and challenges of post-mortem cross-sectional imaging. It serves as a reminder that both, training as well as correlation of imaging findings with autopsy are fundamental to improve our understanding of radiologic findings on post-mortem cross-sectional imaging.     

A canine model for studying endoleak after endovascular aneurysm repair

PURPOSE: The aim of this study was to create an animal model of endoleak after stent-graft placement for abdominal aortic aneurysm (AAA) in which a large aneurysmal sac would be preserved for the testing of techniques for its percutaneous occlusion. MATERIALS AND METHODS: Infrarenal AAAs were created in nine dogs by anastomosis of an isolated segment of the inferior vena cava to the right side of the abdominal aorta in combination with a large anterior patch from the external jugular vein. One hour later, animals underwent percutaneous implantation of polytetrafluoroethylene-covered Z stent endografts with three 3-mm-diameter holes through the fabric. Aortograms were obtained before and after surgery, after endograft placement, and at the time of animal sacrifice at 1 week or 1, 2, 3, or 6 months. Pressures within the aorta and the aneurysm sac were recorded before animal sacrifice. Gross and histologic evaluations of the specimens were then carried out. RESULTS: Immediately after endograft placement, all nine animals had artificial type III endoleaks with angiographic filling of lumbar arteries and veins. One animal died of surgical complications within 2 days of surgery and is not included in our data analysis. One aneurysm ruptured at 1 week. At completion of the study, six endografts were patent and two were occluded. The aneurysm sac had enlarged by approximately 50% in seven animals. At follow-up, type I endoleak was present in three animals, type II endoleak was present in three, and the artificial type III endoleak was present in all six animals with patent endografts. The pressure differential between aorta and aneurysm sac was 36 mm Hg, with a mean aortic pressure of 87 mm Hg +/- 13.3 and a mean aneurysmal sac pressure of 51 mm Hg +/- 28.1. The aneurysmal sac exhibited early thrombus formation at 1 week, which progressed to complete thrombosis in 1-6 months. CONCLUSIONS: The model is technically feasible but would be useful in testing occlusive techniques for residual aneurysm sacs only in the acute phase after endograft placement. It would be not reliable for chronic evaluation because of rapidly progressive thrombosis in most aneurysm sacs and occasional complete thrombosis of the AAA and endograft.     

Endovascular abdominal aortic aneurysm repair in 144 patients: correlation of aneurysm size, proximal aortic neck length, and procedure-related complications.

PURPOSE: During endovascular abdominal aortic aneurysm (AAA) repair, larger aneurysms often present formidable anatomic challenges to the insertion of the delivery catheter and graft deployment. The authors sought to evaluate whether large-diameter aneurysms and those with short proximal aortic necks might be associated with a higher frequency of insertion-related and short-term complications. MATERIALS AND METHODS: From October 1999 to August 2000, 144 patients underwent elective endovascular graft placement for infrarenal AAA disease at the authors' institution. These patients were treated with use of the AneuRx bifurcated endoprosthesis. AAA size (maximum aneurysm diameter) and proximal aortic neck length were compared to estimated blood loss, operative time, accuracy of graft placement, presence of endoleak, intraoperative and postoperative complications (such as limb occlusion or vascular injury), length of hospital stay, and mortality. Statistical methods included correlation analysis and logistic regression. RESULTS: There were 121 men and 23 women whose aneurysms ranged in size from 3 cm to 9.8 cm (mean, 5.6 cm; 95% CI, 5.4-5.8 cm). Endograft insertion was successful in all cases. There were three deaths within 30 days (2.1%) and seven deaths overall (4.9%). There were 43 intraoperative complications (29.9%) in 31 patients (21.5%), most of them minor. Patients with major intraoperative complications had significantly longer procedure times than those without complications (337 vs. 149 min; P <.0001). In the postoperative period (within 30 days), 31 complications (21.5%) occurred in 28 patients (19.4%), again most of them minor. AAA size was unrelated in any way to the rate of complications, but short proximal aortic neck length was associated with more serious intraoperative and postoperative complications (P =.0404 and P =.0230, respectively), and decreased 30-day and overall survival (P =.0240 and P =.0152, respectively). CONCLUSIONS: Endovascular repair of large AAAs can be challenging; however, the size of the AAA does not influence the rate of complications. A short proximal aortic neck is the only significant risk factor for more serious complications.     

Case report: Endovascular repair of a ruptured abdominal aortic aneurysm under local anaesthesia

Abdominal aortic aneurysm (AAA) is a common degenerative condition affecting the elderly population. Rupture carries a high overall mortality. Elective endovascular stent graft repair is well described. We describe a patient with ruptured AAA and co-morbid conditions making him unfit for surgery and general or epidural anaesthesia, who was successfully treated by endovascular stent graft under local anaesthesia.     

CT of abdominal aortic aneurysms--aneurysmal size and thickness of intra-aneurysmal thrombus as risk factors of rupture

In order to seek for the factors to suggest a risk of rupture of abdominal aortic aneurysms (AAA), we measured the largest diameter of AAA and the thickness of intra-luminal thrombus on CT in 72 patients. The mean aneurysmal size was 64 mm in diameter in 9 patients with ruptured aneurysm and 61 mm in diameter in 63 patients with non-ruptured aneurysm respectively (p less than 0.90). The rupture of AAA was seen in 3 of 30 patients with AAA of the small size (less than 50 mm in diameter), in 3 of 16 patients with AAA of the intermediate size (51-66 mm in diameter) and in 3 of 26 patients with AAA of the large size (more than 70 mm in diameter), respectively. The mean intra-luminal thrombus was 9 mm in 9 patients with ruptured aneurysm and 19 mm in thickness in 63 patients with non-ruptured aneurysm respectively (p = 0.05). We concluded from the above results that the aneurysmal size was not important, but the thickness of intra-luminal thrombus was useful for suggestion of a risk of rupture of AAA.