Infrarenal abdominal aortic aneurysm with aortocaval fistula, a rare condition, can be fatal without prompt intervention. The clinical symptoms are complex and varied, so diagnosis is typically confirmed by use of contrast-enhanced multidetector computed tomography. We report our surgical repair of a 13-cm-diameter infrarenal abdominal aortic aneurysm and aortocaval fistula in a 63-year-old orchestral tuba player who had 2 classic symptoms of the condition. The unruptured aneurysm and fistula were complicated by acutely angled vessels, so we performed surgery rather than endovascular repair. The patient recovered fully and was discharged from the hospital. This infrarenal aneurysm with aortocaval fistula is perhaps the largest to have been treated successfully by means of open surgery. In addition to our patient's case, we discuss the history and treatment considerations of this rare combined condition.
More than 15,000 people die each year of ruptured abdominal aortic aneurysm (AAA); in 2013, the Centers for Disease Control ranked it the 15th leading cause of death in the United States in adults 60 to 64 years of age.1 In ultrasonographic studies of men 65 to 80 years old, the prevalence of AAA is 4% to 8%; in women, the prevalence is 4 to 6 times lower.2 The estimated annual pre-hospitalization mortality rate is 59% to 83%, and that upon presentation for medical care, 30% to 80%.3
The risk of AAA rupture increases with aneurysmal diameter2,4 ; typically, diameters ≥6 cm warrant intervention.5 In one study, the relative risk of rupture of an AAA ≥8 cm in diameter was 31.3 (95% CI, 11.1–88.4).5 Most AAAs rupture into the retroperitoneum or peritoneum.6 Rupture of an AAA into the inferior vena cava (IVC) is unusual, and the spontaneous development of an aortocaval fistula (ACF), with or without AAA rupture, is rarer still. More than 80% of reported ACFs have been associated with ruptured AAA.7 Endovascular intervention has had good early results; nevertheless, surgery remains the cornerstone of treatment.3,7
We report the case of a 63-year-old man who presented with a giant infrarenal AAA complicated by an ACF. In addition, we discuss the combined condition's history and its treatment considerations.
In December 2016, a 63-year-old man, a long-time orchestral tuba player, presented at our emergency department with a 12-hour history of abdominal pain. His blood pressure was 90/50 mmHg, and his heart rate was 110 beats/min. Physical examination revealed a pulsatile abdominal mass in the right abdominal wall. Emergency contrast-enhanced computed tomographic angiograms (CTA) confirmed the diagnosis of a giant infrarenal AAA with an ACF (Fig. 1). The 13-cm AAA extended distally to both common iliac arteries. We observed simultaneous filling of the abdominal aorta and IVC, with no signs of retroperitoneal rupture. Acute vascular angulation precluded endovascular intervention (Fig. 2), so the patient was taken for surgery.
After performing a midline laparotomy, we achieved control of the supraceliac abdominal aorta without cross-clamping, controlled the infrarenal aorta and iliac arteries, and exposed the AAA (Fig. 3). We infused systemic heparin intravenously, then cross-clamped the infrarenal aorta and iliac arteries. When we opened the aorta, a large volume of venous blood flowed from the aneurysmal sac. We controlled it by inserting 2 occlusive balloons (volume capacities, 15–30 cc), using a 16F Foley catheter. Autotransfusion was not used. From within the aneurysmal sac, we oversewed a 40 × 15-mm aortocaval communication between the infrarenal aorta and IVC, then ligated both common iliac arteries and the small lumbar arteries. For aortofemoral bypass, we placed an 8-mm Dacron graft to each lower extremity, thus restoring blood flow. The patient was given 3 units of packed red blood cells during the operation.
The patient was extubated on the second postoperative day and stayed 4 days in the intensive care unit, where he was given one unit of packed red blood cells. Postoperative CTA revealed no vascular complications (Fig. 4). On postoperative day 5, he had fever, leukocytosis, and a purulent discharge from the abdominal incision. General surgeons performed an exploratory laparotomy, observed sigmoid colon perforation, and used the Hartmann procedure to repair it.
The patient had no pulmonary or renal insufficiency and only minimal leg edema when he was discharged from the hospital after a 15-day stay. At his 3- and 6-month follow-up examinations, he was doing well.
Syme is credited as being the first to describe ACF (in 1831),8 and Viar and Lombardo reported the first detailed modern case (1952).9 In 1955, in response to Javid and colleagues' case series,10 Cooley noted his own case11 of a poor surgical candidate who recovered after an operation to correct a ruptured AAA with ACF—apparently the first successful repair.
The signs and symptoms of AAA with ACF are varied, often nonspecific, and often associated with unrelated conditions. A pulsatile abdominal mass, abdominal and low-back pain, and an abdominal machinery-like bruit are most typical; other possible symptoms are severe dyspnea, lower-extremity or scrotal edema, ascites, hepatomegaly and liver congestion caused by venous hypertension, and hematuria, oliguria, and renal failure consequent to venous hypertension and decreased median arterial pressure.12 Our patient had abdominal pain, a pulsatile abdominal mass, and leg edema. Results of contrast-enhanced multidetector CTA confirmed the diagnosis.12
Rapid intervention is crucial after diagnosis of ACF.10 A wrong or clinically missed diagnosis contributes to poor operative outcomes, especially in the typical elderly patient who may already be under hemodynamic stress.13 Open surgery and endovascular repair are the treatment options. Supraceliac control of the aorta via an elastic loop is essential for controlling excessive bleeding, especially in an aneurysm that has a short proximal infrarenal neck.14 Although the aneurysmal neck in our patient was long, the position of the AAA necessitated our gaining control of the supraceliac aorta. To protect the kidneys from ischemia, cross-clamping the supraceliac aorta is not recommended unless there is uncontrolled hemorrhage. Profuse venous bleeding from the opened aorta can be controlled by compressing the IVC or by using occlusive balloons.15 Alternatively, hemostasis can be achieved by ligating the infrarenal IVC, iliac veins, or both.16
Endovascular treatment of AAA has been associated with shorter hospital stays and favorable early survival rates. Despite the technical success of endovascular repair, complications such as endoleak can affect long-term outcomes.17 Type II endoleak, more prevalent than the other types, is often caused by unwanted retrograde filling of the sac; it can resolve spontaneously or can worsen after the initial endovascular treatment.18 In one analysis,19 endoleaks occurred in 13 of 26 patients after endovascular ACF repair and spontaneously resolved in 6 instances. The arteriovenous circuit that occurs in ACF may aggravate endoleak patency and in turn cause congestive heart failure, thrombosis, disseminated intravascular coagulation, ACF patency, and further expansion of the sac.19 For these reasons, some operators treat type II endoleak immediately after its diagnosis in association with ACF. We decided to perform surgery in our patient because of acute vascular angulations—almost 90° between the aorta, iliac arteries, and femoral arteries, and 45° to 60° in the aortic neck. In addition, the patient's situation was urgent, and we did not have a hybrid operating room.
A notable factor in our patient's case was his profession. He had played tuba in an orchestra 8 hours daily for 30 years. The expiratory efforts necessary to play wind and brass instruments often replicate the Valsalva maneuver.20 We found no association in the medical literature between tuba-playing and development of a giant AAA with ACF, and we claim none. However, blowing notes on a tuba reproduces cardiovascular changes observed during Valsalva maneuvers; producing loud or sustained notes at high pitches equates with a classic (40-mmHg) Valsalva maneuver.20 Diaphragmatic movement while playing low notes results in a low resistance to expiration, whereas high notes necessitate strenuous or strained expiration. In the latter, high intrathoracic pressure can reproduce Valsalva effects that would change blood pressure, heart rate, stroke volume, and peripheral vascular resistance.20 Furthermore, in the mechanism of ACF, the decreased peripheral resistance and diastolic hypotension cause a sharp increase in cardiac output that can rapidly lead to left ventricular high-output decompensated cardiac failure, particularly in patients who have underlying heart disease.6 Without further investigation, it is unclear whether our patient should continue to play the tuba, or if any wind or brass instrumentalist should continue to play, in the presence of an existing or repaired AAA.
Reviewers19 documented only 40 PubMed-listed articles about AAA with ACF from 1999 through 2014, involving 67 patients, 41 surgeries, and 26 endovascular repairs. Our supplemental search (1999–2017) disclosed a few more reports of giant AAA (≥13 cm) with ACF; however, those patients died before, during, or days after surgery. We found no AAAs >13 cm associated with ACF.14,21 Accordingly, our patient survived perhaps the largest unruptured infrarenal AAA with ACF to have been treated surgically.
From: Departments of Cardiovascular Surgery (Drs. Bektas, Bitargil, and Koramaz) and General Surgery (Dr. Omeroglu), Sisli Hamidiye Etfal Research and Training Hospital, 34371 Sisli, Istanbul, Turkey