Background: We have performed elective surgery for abdominal aortic aneurysm (AAA) in accordance with our policy that 5 cm is the best threshold for repair of AAA. We conducted a retrospective study to determine whether our policy is valid in all our patients with AAA. Methods: All 260 patients who presented at Tohoku University Hospital with AAAs ≥4 cm between 1996 and 2003 were reviewed. We examined the size of the aneurysm at the first presentation, operation for AAA, length of survival and cause of death. We divided patients into two groups. One was the patients who received early surgery and the other is those who were observed and follow up. The latter group was further divided in two subgroups: the 4 cm-observation group in which the size of the aneurysm was smaller than 5 cm in diameter and the 5 cm-observation group in which the size of aneurysm was larger than 5 cm at first presentation. We investigated the outcome and compared the groups. Results: Among these patients, 125 patients (48.1%) underwent early elective operation (early surgery group) and 135 patients (51.9%) were not offered operative treatment (4 cm-observation group: 92,5 cm-observation group: 43). Almost all patients in the early surgery group had an AAA of 5 cm or greater. In 52 cases in the observation group, additional elective surgery was performed during the follow-up period, and all of those 52 patients had an AAA of 5 cm or greater. Rupture of the aneurysm occurred in 14 cases in the observation group and all ruptured aneurysms had reached 5 cm. No rupture occurred in aneurysms smaller than 5 cm in diameter. The cumulative incidence of probable rupture was significantly higher in the 5 cm-observation group than in the 4 cm-observaton group (p<0.0001). The cumulative 5-year survival rate of the early surgery group (77.8%) was significantly higher than that of the observation group (58.3%). However, the outcome in the 4 cm-observation group was almost same as in the early surgery group and the estimated prognosis curve of the Japanese normal population based on Life Table for Japan; therefore the outcome was significantly poorer in the 5 cm-observation group. The operative mortality rate was 0.6% in the patients who received elective surgery and there was no statistical significance in the cumulative survival rate after operation between the early surgery group and the additional elective surgery after observation (76.8% and 75.1% in 5-year survival rate, prospectively). There was also no statistical significance in the outcome after operation between the 4 cm-observation group and the 5 cm-observation group (74.8% and 78.6% in 5-year survival rate, prospectively). Conclusion: From our present study, it is valid that AAA smaller than 5 cm in diameter should be observed and followed up.
A 70-year-old man was transferred to our hospital with unstable vital signs and an APACHE III score of 47. Multidetector-row computed tomography (MDCT) detected acute aortic dissection, accompanied with bilateral hemothorax, thoracic vertebral fracture, and subarachnoid hemorrhage. The aortic dissection was immediately treated by transluminally placed endovascular grafting (TPEG), which covered the level Th-5 to -12 of the thoracic aorta. Right thoracotomy was made to coagulate the pleural bleeding due to the vertebral fracture, which aggravated the right hemothorax even after TPEG. The postoperative course was uneventful and there was no paraplegia. The patient was discharged on the 44th postoperative day. Postoperative computed tomography confirmed disappearance of the subarachnoid hemorrhage and the hemothorax, and successful placement of the stent-graft with spared patency of the celiac artery. Not only was it feasible for the whole body examination for other trauma, MDCT enabled precise preoperative planning for the emergency TPEG. Since blunt aortic injury is frequently accompanied by multiple trauma, TPEG could treat the complicated conditions less invasively, with a minimal amount of preprocedural anticoagulant for the aortic surgery, and with a reduced volume of blood loss.
A 69-year-old woman presented with sudden onset severe lower limb ischemia. A huge embolus originating from a left atrial myxoma had completely occluded the aorta and bilateral common iliac artery. Emergency operation was performed and a left atrial myxoma was extirpated through a superior transseptal approach on cardiopulmonary bypass (CPB). CPB was continued for the purpose of preventing shock after reperfusion of the limb and a saddle embolus of the aorta and bilateral common iliac artery was removed 10 hours after the onset of limb ischemia. Myonephropathic metabolic syndrome (MNMS) occured and required continuous hemodiafiltration (CHDF), but she fully recovered after 48 days of CHDF and hemodiafiltration (HDF) postoperatively. The dilution ultrafiltration method (DUF) during operation and early CHDF were effective for therapy of MNMS.
A 14-year-old boy was admitted to our center with sudden back pain and impending rupture of an abdominal aortic aneurysm was diagnosed by computed tomography (CT) scan. He underwent urgent replacement of the abdominal aorta. The patient had been evaluated for a cerebral aneurysm at 7 years of age and hypertension at 13 years of age. He also had a renal artery aneurysm. Post-operatively, the disease was identified as type IV Ehlers-Danlos syndrome (EDS) based on the multiple aneurysms, thin skin with visible veins, and loose joints. In type IV EDS extreme fragility of the arteries is associated with multiple aneurysm formation, spontaneous rupture, and dissection. Most deaths result from arterial rupture. Patients with type IV EDS should probably be evaluated at regular intervals by CT and related techniques for early detection of aneurysms.
A 81-year-old man was admitted to our hospital because of sudden lumbago and coolness in the lower extremities. A computed tomography scan of the abdomen showed a totally thrombosed abdominal aortic aneurysm. At 8 hours after the onset of symptoms, a bifurcated graft was inserted after resection of the aneurysm and a thrombectomy. After revascularization, left hemicolectomy was performed and a colostomy was established because of an ischemic change of the descending colon. The patient died of multiple organ failure due to reperfusion syndrome on the second postoperative day. Acute thrombosis of an abdominal aortic aneurysm is rare, but mortality rates are high (>50%) because of reperfusion syndrome, myonephropathic metabolic syndrome, acute renal failure or cardiovascular deterioration. Once a diagnosis has been established, it is recommended to perform revascularization as soon as possible.
A 44-year-old man with Marfan syndrome underwent total aortic graft replacement including Bentall's procedure and reconstruction of the visceral branches 10 years previously. He was brought by ambulance because of abdominal pain high fever with diarrhea and tarry stool. We performed emergency laparotomy on the suspicion of intestinal ischemia. Intestinal necrosis with perforation was recognized, from the ascending colon to the transverse colon. We diagnosed ischemic necrotic colitis due to arterial thrombosis because pulsation of the superior mesenteric artery and celiac artery was not clear. We performed right hemicolectomy and splenectomy, plus retrograde mesenteric and celiac bypass by a saphenous vein graft. The patient's postoperative course was uneventful. Postoperative angiography revealed thrombotic occlusion of the celiac and superior mesenteric arteries.
Pseudocoarctation is a rare anomaly in the descending thoracic aorta and had been considered by most as a benign condition, warranting no specific therapy. In this article we present a juvenile patient who had an aortic aneurysm as a complication of pseudocoarctation. The patient was a 13-year-old boy with an asymptomatic mediastinal mass discovered on chest x-ray. Computed tomography and magnetic resonance angiogram demonstrated kinking in the distal aortic arch with a saccular aneurysm of the descending aorta. There was no significant pressure differential between arms and legs, and no evidence of increased collateral circulation (rib notching, etc). At operation, an extremely friable, saccular aneurysm of the descending thoracic aorta was found distal to a buckled and constricted aortic isthmus. The walls of the aneurysm were so thin that the aortic blood flow could be observed through it. With the use of hypothermic circulatory arrest, resection of the aortic aneurysm and buckled aorta just distal to the left subclavian artery, and insertion of a woven Dacron graft was performed. Microscopic examination revealed fragmented smooth muscle fibers in the media and small areas of mucoid degeneration. The patient progressed well without any neurological deficiency.
A 65-year-old man was referred to our emergency center on the suspicion of an isolated internal iliac artery aneurysm perforated into the rectum. Intraoperative findings revealed a fist size of aneurysm adherent to the rectal colon and suspected anaerobic bacteria infection because of the putrescent smell. The aneurysm was resected except for the posterior wall that tightly adhered to the anterior wall of the rectum. No fistula connecting with the colon was revealed. During his hospital stay, we gave him intravenous antibiotics. He was discharged 42 days after the surgery. Oral administration of antibiotics was continued for 20 months after surgery then halted. He is free from recurrence of infection for 25 months after surgery.
We report rare case of aortic dissection with coexisting chronic fusiform abdominal aortic aneurysm. The patient presented with unbearable back pain of sudden onset, followed by intolerable ischemic pain in the right lower limb. Contrasted computer tomography detected an acute type B dissection and the enlarged maximum diameter of the abdominal aneurysm of 45 mm. The arterial blood supply of the right limb was extremely compromised due to the enlarged false lumen, which impaired the circulation. Aortic replacement with distal anastomoses with the right common femoral and left common iliac artery was performed, after partial resection of an intimal flap in the abdominal aorta, creating re-entry of the false lumen. However, the hemodynamics of the patient remained unstable until the resection of the ileum and total colectomy, because of the bowel necrosis caused by concomitant dissection in the superior mesenteric artery. The case has been forced to receive intra-venous hyper-alimentation on an outpatient basis. This experience suggested the importance of appropriate surgical treatment followed by prompt and accurate diagnosis, and that caution should be exercised about the rare but serious condition of splanchnic ischemia under these circumstances.
We report an operative case of axillobifemoral bypass graft occlusion after repair of an infected aortic aneurysm. Successful revascularization was achieved by descending aorta bifemoral bypass grafting. A 58-year-old man was admitted to our hospital. He had acute limb ischemia induced by extraanatomical bypass graft occlusion, which had been conducted in a previous operation for an infected aortic aneurysm caused by Sallmonella. Surgical revascularization was performed with 7th intercostal thoracotomy and a retroperitoneal approach. Instead of the infrarenal aortic stump where the omentum was previously transferred, the descending aorta was chosen as an inflow source. A y-shaped Dacron prosthesis was anastomosed to the descending aorta, left external iliac artery, and right femoral graft. The postoperative course was uneventful. The descending aorta can be an alternative inflow source if the axillofemoral bypass graft was occluded in a patient who previously underwent operation for an infected infrarenal abdominal aortic aneurysm.