Aortocaval Fistula After Stent-Graft Repair

Endovascular treatment of an aortocaval fistula caused by a late type II endoleak

An aortocaval fistula (ACF) is a rare complication of abdominal aortic aneurysms (AAAs) and constitute <1% of all AAAs, which increases from 2% to 6.7% in ruptured AAAs. Unlike other aortic ruptures, most ACFs are not associated with significant blood loss on admission. The traditional treatment strategy has been open surgery, which is associated with a high mortality rate. Endovascular repair has been performed; however, the results are difficult to interpret due to the low incidence of ACFs and the absence of cases reported with a long follow-up duration. We report the case of a 78-year-old man with previous endovascular aneurysm repair performed in 2015, who presented to our emergency department 6 years later with abdominal pain. A computed tomography angiography scan showed type Ia, Ib, and II endoleaks and an ACF. The endoleaks were selectively treated, and the ACF was covered with a polytetrafluoroethylene endograft inserted in the inferior vena cava. In our single-case experience with a medium-term follow-up of 24 months, our treatment was safe and effective for ACF closure, with no further signs of endoleak or graft thrombosis. We conducted a literature review of reported cases in which a covered stent graft was used for ACF treatment. Although no guidelines are currently available regarding this rare late complication after endovascular aneurysm repair, using a covered stent placed in the inferior vena cava to treat an ACF could be a viable option in selected cases.

Open Surgery and Endovascular Techniques in Treatment of Acute Abdominal Arteriovenous Fistulas

Acute abdominal arteriovenous fistulas in the setting of ruptured abdominal aortic aneurysms are a life-threatening condition; thus, a prompt diagnosis is required for proper treatment. Open, endovascular, and hybrid repair have been proposed for their management, with pros and cons for each method. In particular, the evolution of endoluminal techniques guarantees an increasing feasibility of these procedures, and a significant reduction in morbidity and mortality rates was usually associated with open surgery. Nevertheless, some concerns still remain regarding the midterm and long-term follow-up. The aim of this article was to review and compare the reported clinical and technical results of conventional open surgery and endoluminal techniques in this scenario and to report the case of an acute aorto-iliac fistula due to a ruptured common iliac artery aneurysm into the iliac vein that was managed by endovascular repair at our institution.

Endovascular Therapy of Spontaneous Aortocaval Fistulae Associated with Abdominal Aortic Aneurysms

We report a case of an abdominal aortic aneurysm (AAA) associated with an aortocaval fistula managed with endovascular techniques. The patient had a known AAA, and on the latest computed follow-up tomographic scan, evidence of fistulization between the aorta and the vena cava was suggested, which was later corroborated by standard contrast angiography. His comorbidities precluded an open repair, and this prompted consideration for an endovascular intervention. Successful exclusion of the AAA was performed, with no evidence of endoleaks or persistence of the fistula. The endovascular approach provides an efficacious alternative to traditional methods for repair of an aortocaval fistula, which is especially important in elderly patients with several comorbidities.

Aortocaval Fistula: Is Endovascular Repair the Preferred Solution?

BACKGROUND

To compare outcomes of open and endovascular repair of aortocaval fistulas (ACFs) in the setting of abdominal aortic aneurysms (AAAs).

METHODS

A literature review was undertaken on Pubmed from 1999 to 2014 to identify reported cases of both endovascular and open repair of ACF, including the index case, presented here. Primary outcomes for endovascular repair were: complications, presence of endoleak, and death. Primary outcomes for open repair were: complications and death.

RESULTS

Forty articles were reviewed with a total of 67 patients, including the index case. Endovascular approach was used in 26 patients (39%). Endoleaks were present in 50%, whereas similarly 46% of patients had a reported complication. Five deaths (19%) occurred in the endovascular group. Open repair was performed in 41 cases (61%). The rate of complication and the death in open repair were 36% and 12%, respectively (P = 0.327 and P = 0.910, respectively) compared with endovascular. Mean follow-up was 7.7 months for the endovascular group and 8.5 months in the open group.

CONCLUSIONS

Previous demonstrations of high morbidity and mortality with open repair of ACF in the setting of AAA have motivated endovascular approaches. However, endoleaks are a significant problem and were present in 50% of ACF cases. The continued presence of an endoleak in the setting of an ACF may result in persistence of the ACF, unlikely thrombosis of the endoleak, and continued sac enlargement. Endovascular repair presents theoretical benefit, yet is not associated with a reduced rate of complication or death versus open repair in this contemporary review.

Endovascular Treatment of Major Abdominal Arteriovenous Fistulas

Purpose:

To review the different outcomes of the endovascular repair of major abdominal arteriovenous fistulas (AVFs).

Methods:

An online systematic review of the literature was undertaken to identify all reported cases of endovascular repair of major AVFs, covering 9 major databases as well as relevant journals up to September 2013. Our own case was included. The primary outcome was technical success and mortality, the secondary outcome was the rate of complications and the operators’ recommendations.

Results:

Forty-eight articles were reviewed totaling a number of 54 patients including our own. The most common fistula site was the aortocaval segment. Aortic stent grafts were used in 78% of patients. Technical success was 94%. Intraoperative mortality was 0% with a 90-day mortality of 10%, half of which were not related to the primary pathology. Of the successful procedures, 12% of patients had major complications. One died before reintervention. All others had uneventful recoveries; 21% had minor complications treated conservatively. The majority of authors were in favor of this treatment modality.

Twenty years of experience in the treatment of spontaneous aorto-venous fistulas in a developing country

BACKGROUND

One of the rare forms of abdominal aortic aneurysm (AAA) rupture is the rupture into great abdominal veins such as the inferior vein cava (IVC), the iliac veins, or the left renal vein, with the formation of direct or indirect aorto-caval fistula (ACF). The purpose of the present study was to summarize 20 years of experience at a single referral center for vascular surgery in a developing country, and to discuss the clinical presentation, diagnosis, treatment options, and outcome of patients with spontaneous aorto-venous fistulas (AVF) caused by ruptured aortic aneurysms.

MATERIALS AND METHODS

Retrospective database review identified 50 patients treated in our institution for aorto-venous fistulas (AVF) caused by spontaneous AAA rupture in the 20 years 1991-2010. Pulsating abdominal mass and low back pain were the leading symptoms on admission in our patients. Signs of shock, congestive heart failure, or pelvic and lower extremity venous hypertension were present in 48%, 26%, and 75% of the patients, respectively. Diagnosis of AVF was based on physical examination, duplex ultrasonography, conventional angiography, or multislice computed tomography (MSCT). In 40% of the patients the presence of AVF has not been recognized before surgery. All patients were treated with open surgery.

RESULTS

After proximal and distal bleeding control the fistula was closed with direct suture (92%) or patch angioplasty (8%). Aortic reconstruction followed with tubular (22%) or bifurcated (78%) synthetic graft. Six (12%) patients died. The causes of death were excessive intraoperative blood loss, myocardial infarction, left colon gangrene and multiple organ failure.

CONCLUSIONS

Spontaneous AVFs caused by aneurysmal rupture are not uncommon, and they require prompt surgical or endovascular treatment. Routine use of multislice CT in patients with acute aortic syndrome is probably the best way to the correct diagnosis of aorto-venous fistulas and planning of the optimal treatment.

Emergency endovascular repair of aortocaval fistula--a single center experience

PURPOSE

To review the outcomes of patients undergoing emergency endovascular repair of aortocaval fistula (ACF) secondary to abdominal aortic aneurysm (AAA).

CASE REPORT

Four consecutive patients who underwent emergency endovascular repair of ACF associated with AAA in a tertiary institution between 2002 and 2009. Of the 4 patients, 3 had initially been misdiagnosed and managed for several days by other specialists for their symptoms prior to diagnosis of their ACF. Three patients died in the early postoperative period. The fourth patient made a satisfactory postoperative recovery but subsequently required further endovascular surgery to treat a persistent type 1 endoleak.

CONCLUSIONS

Our experience illustrates the importance of early diagnosis and management of ACF. Even in experienced hands, the management of spontaneous ACF associated with AAA is challenging. Endovascular surgery may still have a role in improving outcomes in these patients.

Endovascular stent-graft repair of major abdominal arteriovenous fistula: a systematic review

PURPOSE

To evaluate the outcomes of endovascular stent-graft repair of major abdominal arteriovenous fistulas.

METHODS

The English literature was systematically searched using the MEDLINE electronic database up to January 2009. All reports on endovascular stent-graft repair of major abdominal arteriovenous fistula were considered. Our experience of abdominal arteriovenous fistula was involved in the data analysis. The primary outcome measures were technical success and perioperative, 30-day, and overall mortality.

RESULTS

Data for the final analysis were extracted from 21 papers reporting on 22 patients and from the medical records of a patient treated at our institution. The most common causal associations of these fistulae were the presence of an aortoiliac aneurysm and previous endovascular aneurysm repair, accounting for 56% and 13% of all associations, respectively. The technical success rate was 96% (22/23). No perioperative or 30-day mortality was noticed during a mean follow-up of 9 months. The most common procedure-related complication was type II endoleak, which was found in 22% (5/23) of the patients. This event was either self limiting or required minimal percutaneous intervention.

CONCLUSION

Endovascular stent-graft repair of major abdominal arteriovenous fistula is a safe and effective treatment option, with good short- and midterm results. However, no long-term data exist, and larger series are required to draw solid conclusions regarding the outcomes of this method.

Unusual forms of ruptured abdominal aortic aneurysms

Over 95% of abdominal aortic aneurysms (AAAs) rupture into the retroperitoneal space. Rare types of AAA ruptures comprise ruptures into the inferior vena cava with aortocaval fistula formation (ACF), ruptures into the duodenum with formation of a primary aortoduodenal fistula (ADF), and chronic contained ruptures (CCRs). This article presents a study of 41 cases with unusual forms of ruptured AAA of a series of 506 patients with AAA rupture treated within a 14-year period. There were 11 cases of CCR, 5 cases with ADF, and 25 cases with ACF. The correct preoperative diagnosis was established in 6 (of 11) cases of CCR, in 2 (of 5) cases of primary ADF, and in 13 (of 25) cases of ACF. AAA replacement was performed in 8 cases using a tube graft, whereas a bifurcated graft was used in 31 patients because of the distant extent of the atherosclerotic/aneurysmatic lesions engaging iliac arteries. Two patients had an axillobifemoral bypass. The overall 30-day mortality rate was 19% (8 of 41), with subgroup mortality rates of 0 (CCR), 60% (ADF), and 20% (ACF). Diagnosis and treatment are simplest in cases of CCR and the most complicated in cases of ADF.

Surgery for ruptured abdominal aortic aneurysm with an aortocaval and iliac vein fistula

The purpose of this study was evaluate the operative procedure and outcome of abdominal aortic aneurysm (AAA) patients with aortocaval fistula (ACF) and iliac vein fistula. From 1982 through 2004, we experienced five AAA patients associated with spontaneous aortocaval and aortoiliac venous fistula who underwent repair of AAA. Three patients were in hypovolemic shock, including one patient with cardiopulmonary arrest on admission who required cardiopulmonary resuscitation before surgery. These three ACF patients with hypovolemic shock underwent emergency operation and two patients with stable hemodynamic state underwent urgent operation. One of two ACF patients with stable condition was associated with unstable angina. One AAA patient with ACF-complicated angina underwent AAA repair with coronary artery bypass grafting; the remaining four patients underwent 3 bifurcated graft and 1 tube graft implantation. All surgical treatment of the fistula included direct closure within the aorta under digital compression in four patients and inferior vena cava clamp in one. The mortality rate was 25%. One ACF patient with retroperitoneal hematoma died of bleeding. Survival for ACF depends on early diagnosis and prompt surgical repair. Aortocaval fistula complicated with a rupture of aneurysm into retroperitoneal space had a severe fatal prognosis compared with uncomplicated ACF.

Bilateral Long Saphenous Bruits: A Marker of Aortocaval Fistula

INTRODUCTION

The authors present a case of an aortocaval fistula manifesting clinically with bilateral long saphenous bruits. This sign has not been previously described.

REPORT

An 85-year old lady presented with a 3-week history of abdominal pain radiating to her back. Examination revealed a bruit to the right of the midline associated with bilateral long saphenous bruits. A provisional diagnosis of an aortocaval fistula was confirmed on computerised tomography. The fistula was excluded by aortobiiliac bypass and the patient made an uneventful recovery.

DISCUSSION

Aortocaval fistulae are rare. They should be suspected if abnormal pulsations are felt to the right of the midline in association with bruits in the region of the inferior vena cava. The presence of long saphenous bruits suggests saphenofemoral incompetence due to arterialised, reversed venous flow dynamics and strengthens the clinical diagnosis of aortocaval fistula.