Characteristics, Management, and Outcomes of Surgically Treated Arteriovenous Fistula Aneurysm in Patients on Regular Hemodialysis.

BACKGROUND: To investigate the clinical characteristics, surgical interventions, and outcomes of arteriovenous fistula (AVF) aneurysms, we retrospectively analyzed patients on regular hemodialysis (HD). METHODS: We conducted a cohort study of all patients with HD access who presented with AVF aneurysms and underwent operative procedures over a 11-year period. Patients' demographics, comorbidities, vascular access characteristics, management of aneurysms, complications, and outcomes were analyzed. RESULTS: Of the 700 end-stage renal failure patients, 530 patients were maintained on HD (130 through PermCath and 400 through AV access in terms of AVF and arteriovenous graft). We identified 129 patients who developed AV aneurysms, and 40 of them required surgical interventions (24 men and 16 women) with a mean age of 58 ± 14.6 years. The 40 patients who developed AVF aneurysms underwent 43 surgical interventions. The majority of aneurysms were presented with thinning and ulceration (82.5%) of the overlying skin. Thirty-four patients had true aneurysms and 6 had pseudoaneurysms. The aneurysmal AVF comprised 26 brachiocephalic fistulas, 9 radiocephalic fistulas, 3 brachial artery grafts, 1 ulnar-basilic fistula, and 1 Fem-Fem graft at presentation. Patients were treated mainly with ligation (13; 32.5%), excision and repair with graft interposition (15; 37.5%) or vein interposition (11; 27.5%), and end-to-end AVF (1; 2.5%). The median follow-up postsurgery duration was 53 months (range 1-192) and the median duration from fistula creation to the surgical intervention was 52 months (range 4-182). On follow-up, 34 patients continued on HD, while 5 underwent renal transplantation and 1 shifted to peritoneal dialysis. The overall all-cause mortality rate was 37.5% and the leading causes of mortality were sepsis/pneumonia (60%), myocardial infarction, and heart failure (40%). CONCLUSIONS: In HD patients, the rate of AVF aneurysmal formation is high with a significant rate of morbidity and mortality. Therefore, timely and appropriate evaluation and surgical intervention are crucial.

Accuracy of an internationally validated genetic-guided warfarin dosing algorithm compared to a clinical algorithm in an Arab population.

PURPOSE: To identify the impact of CYP2C9*2, *3, VKORC1-1639 G>A and CYP4F2*3 on warfarin dose in an Arab population. To compare the accuracy of a clinical warfarin dosing (CWD) versus genetic warfarin dosing algorithms (GWD) during warfarin initiation. METHODS: A cohort of Arab patients newly starting on warfarin had their dose calculated using CWD published in www.warfarindosing.org and were followed for 1 month. Each patient provided a saliva sample. DNA was extracted, purified and genotyped for VKORC-1639 G>A, CYP2C9*2, CYP2C9*3 and CYP4F2*3. After reaching warfarin maintenance dose, the dose was recalculated using the GWD and median absolute error (MAE) and the percentage of warfarin doses within 20% of the actual dose were calculated and compared for the two algorithms. RESULTS: The study enrolled 130 patients from 12 Arabian countries. Compared to those with wild type, carriers of reduced function alleles in CYP2C9 required significantly lower median (IQR) warfarin weekly dose [24.5 (15.3) vs. 35 (29.8) mg/week, p=0.006]. With regards to VKORC, patients with AA genotype had a significantly lower median (IQR) weekly warfarin dose compared to AG and GG [21(10.5) vs 29.4 (21), p<0.001 for AA vs AG, p<0.001 for AA vs GG]. The MAE (IQR) for the weekly dose of the GWD was significantly lower compared to CWD [8.1 (10.5) vs 12.4 (12.6) (p<0.001)]. CONCLUSION: CYP2C9 and VKORC1 variants are important determinants of warfarin dose in the Arab population. The use of the genetic and clinical factors led to better warfarin dose estimation when compared to clinical factors alone.

Presentation, management and outcome of aorto-esophageal fistula in young patients: two case-reports and literature review.

Aorto-esophageal fistula (AEF) is a rare serious surgical event. The first case developed hematemesis 2 weeks post-sleeve gastrectomy. A covered esophageal stent was placed endoscopically. The esophageal stent implantation was followed by massive bleeding due to an AEF. A thoracic endovascular aortic repair (TEVAR) was performed. Aggravated by infection of the aortic stent, another massive bleed occurred after 1 year. The final procedure was resection of the descending aorta with reconstruction using a bovine pericardial patch. The second case presented with hematemesis post-motor vehicle accident. AEF was confirmed by aortogram and treated by TEVAR followed by fully covered esophageal stent. The patient declined definite surgery. In conclusion, initial endovascular approach is useful as a bridge procedure. Once the patient hemodynamics are stabilized, a definitive surgical repair is required. The post-repair infection and life-long antibiotics could be overcome by using bovine pericardial grafts.

Isolated Dissections of Superior Mesenteric and Celiac Arteries Associated With Aortic Ectasia.

Arterial dissection is defined as a tear in the inner lining of arteries, leading to the passage of blood between the layers and resulting in a false lumen. Arterial dissection involving the aorta is commonly seen in clinical practice; however, dissections involving the celiac and superior mesenteric arteries are quite rare. Even rare are isolated multiple visceral arterial dissections. A 59-year-old male with uncontrolled hypertension presented with epigastric pain. CT angiography revealed isolated dissection of the celiac and superior mesenteric arteries with ascending aortic ectasia, with no features of ischemia or organ dysfunction. He was managed conservatively with analgesics & anticoagulation. Repeat CT angiography after six months of anticoagulation therapy showed no progression of the disease. Isolated multiple visceral arterial dissection is a rare vascular disease that requires a high index of suspicion to diagnose. CT angiography is a useful imaging modality that helps not only in diagnosis but also in choosing a treatment plan. Though treatment options are controversial, conservative treatment with anticoagulation should be considered in uncomplicated cases of visceral arterial dissections.