Primary aortoenteric fistulae: the challenges in diagnosis and review of treatment.

Primary aortoenteric fistula (PAEF) is a potentially fatal condition which poses a considerable diagnostic challenge because of its infrequency and the nonspecific presentation. We report the case of a 61-year old woman who presented to her general practitioner with nonspecific and intermittent rectal bleeding, hematemesis, and weight loss. Four days later, she presented to the emergency department with worsening symptoms. The investigations revealed a new small 3.8-cm abdominal aortic aneurysm on computed axial tomography (CT), however, no evidence of a fistula was observed either on CT scan or endoscopy. Two days later, she became unstable requiring an emergency laparotomy and was taken to the operation theater for an en bloc resection of a segment of the aorta and duodenum with exclusion of the duodenum with an inline reconstruction of the aorta using a Dacron graft for a PAEF. The published data were reviewed to address the issues of optimal diagnostic methods and management of PAEF.

Utility of portable continuous-wave Doppler examination in screening for postoperative deep vein thrombosis.

BACKGROUND: Early and accurate diagnosis of post-surgical deep vein thrombosis (DVT) can be difficult and time-consuming, even with duplex ultrasonography. Portable continuous-wave Doppler ultrasonography may be useful in screening patients for postoperative DVT. Further confirmation of Doppler-positive cases by duplex ultrasound might then be more cost-effective. METHODS: All major post-surgical patients from the departments of general surgery, orthopaedic surgery and colorectal surgery were screened on the third postoperative day for DVT by assessing the quality of the flow signal ("whoosh") obtained by placing the probe over the femoral vein and subsequently over the popliteal vein, both with a distal squeeze, as well as assessment of phasic flow with respiration. An absent or attenuated "whoosh" was judged to be suspicious for DVT and required formal duplex ultrasonography. The first 800 consecutive patients were studied to determine the sensitivity, specificity and accuracy of portable Doppler ultrasonography for DVT screening. RESULTS: Twenty-four cases of DVT were diagnosed, comprising seven cases in the proximal veins and 17 cases in the calf veins. The sensitivity of Doppler ultrasonography was 12.5% and the specificity was 96.8%. The positive and negative predictive values were 10.7% and 97.3%, respectively. CONCLUSIONS: Portable Doppler ultrasonography does not have adequate accuracy to be used as a quick screening tool for DVT.

Duplex ultrasonography arteriography as first-line investigation for peripheral vascular disease.

INTRODUCTION: The gold standard for evaluation of the lower extremity arterial tree is catheter angiography. Duplex arterial-occlusive imaging or duplex ultrasonography arteriography, a noninvasive technique, is used as the first-line investigation in patients with peripheral vascular disease at our centre. Based on the results of duplex imaging, patients who require angiographic intervention then proceed with simultaneous catheter arteriography and intervention. This study aimed to compare the results of duplex imaging alone as the first-line investigation against the eventual results of catheter angiography, and to assess the impact of the former on patients' clinical outcomes. METHODS: All cases involving patients who underwent duplex imaging followed by angiographic intervention, from May 2008 to February 2009, were discussed at weekly interdisciplinary meetings. Only patients who underwent lower limb imaging were included in the study. Those who were involved in grafts and stent surveillance studies, as well as those with incomplete duplex images were excluded. RESULTS: During the study period, 113 duplex imaging studies of the lower limb followed by percutaneous transluminal angioplasty were performed at our hospital for peripheral vascular disease. The iliac artery was visualised in 40 images, but could not be visualised in 73 images. There was a potential change in management in three cases due to radiological differences between the duplex images and angiography films. CONCLUSION: In our series, duplex imaging was found to be accurate enough to guide initial clinical management of patients with peripheral vascular disease. This modality is the preferred first-line investigation for such patients at our centre.

Bare nitinol stent enabled recanalization of long-segment, chronic total occlusion of superficial femoral and adjacent proximal popliteal artery in diabetic patients presenting with critical limb ischemia.

PURPOSE: To evaluate our experience of limb salvage with bare nitinol stent enabled recanalization of long length occlusions of superficial femoral artery (SFA) and adjacent proximal popliteal artery (PPA) in diabetic patients. METHODS: A total of 573 patients underwent 842 lower limb interventions from August 2006 to September 2008 at our institute. A retrospective review was done of diabetic patients undergoing recanalization of long length SFA/adjacent PPA (>10 cm) occlusions with self expanding bare nitinol stents evaluating their impact on limb salvage. RESULTS: Forty-four patients (mean age 65.2 years, M:F 25:19) underwent 49 long-length (>10 cm) SFA/PPA stenting procedures over a period of 26 months. Diabetics comprised 66% of patients (n=29, mean age: 63.7 years, M: F 19:10). The infrapopliteal distal run-off in this diabetic subgroup comprised one vessel (n=14/29, 48%), two vessels (n=12/29, 41%), and three vessels (n=3/29, 10%). The spectrum of critical limb ischemia included rest pain (n=8), ulcer (n=7) and gangrene (n=14). The lengths of occlusions recanalized were 10-39 cm. A total of 58 stents (individual length 10-17 cm, average diameter 6 mm, mean 2 stents per patient) were placed with average length of stented segment being 23.8 cm. Four patients had stents placed through ipsilateral popliteal artery approach with rest placed through femoral artery approach. Significant complications of the procedure included distal embolization (n=3) successfully managed with thrombolysis and popliteal arteriovenous fistula in one patient undergoing recanalization through popliteal approach, managed with covered stent placement. No procedure related mortality occurred during thirty-day follow-up period. All were followed up over an average duration of twelve months post-procedure. Three patients died due to associated medical conditions during this period. The following amputations were done on follow-up (three toe amputations, five forefoot amputations, three below-knee amputations, two above-knee amputations). The overall limb salvage rate was 80%. CONCLUSION: Our study shows beneficial result of SFA/PPA stent placement in diabetic occlusions with significant concomitant infrapopliteal disease.

Extra-anatomic revascularization and aortic exclusion for mycotic aneurysms of the infrarenal aorta and iliac arteries in an Asian population.

OBJECTIVES: To study the clinical presentation, management and eventual outcome of patients with mycotic abdominal aortic aneurysms managed with aortic exclusion and extra-anatomic reconstruction. DESIGN: A retrospective chart review of 18 cases treated at a single institution. METHODS: Medical records of 18 patients admitted to our institution from October 1997 to July 2006 with a diagnosis of mycotic abdominal aortic aneurysms were reviewed. In all cases, the diagnosis was confirmed by abdominal computed tomography and empirical parenteral antibiotics were administered. Seventeen patients had surgical debridement, aneurysm exclusion, and extra-anatomic reconstruction. The antibiotics were continued in the postoperative period for 6 weeks. RESULTS: Immunosuppression was present in 72%, with diabetes mellitus present in 56%. Salmonella sp was the causative organism in 72% of cases. Most patients presented late, with a 67% incidence of contained rupture. Seventy-two percent needed early or emergency surgery with less than 1 week of preoperative antibiotics. Disease-specific mortality was 39% (7/18). There was 1 late death during the mean follow-up period of 34 +/- 26 months. One patient with an infrarenal aneurysm arising relatively close (neck, 2 cm) to the renal arteries died on table when proximal ligatures cut through the friable aortic wall, resulting in uncontrollable exsanguination. One third of patients on long-term graft surveillance developed mild to moderate stenosis at the anastomotic site. CONCLUSIONS: Empirical antibiotics must be started early, aiming to achieve 1 week of antibiotics prior to surgery. In the Asian population, 3 characteristics are apparent: (1) most patients are immunocompromised; (2) patients present late in the course of disease; and (3) Salmonella is usually responsible. Extra-anatomic bypass may provide a safe option for revascularization of mycotic aneurysms of the iliac arteries and infrarenal aorta.