NavYash Gupta

Does hostile neck anatomy preclude successful endovascular aortic aneurysm repair

OBJECTIVES Poor outcomes have been reported with endovascular aneurysm repair (EVAR) in patients with hostile neck anatomy. Unsupported endografts with active fixation may offer certain advantages in this situation. We compared EVAR results using the Ancure (Guidant) endograft in patients with and without hostile neck anatomy. METHODS Records of EVAR patients from October 1999 to July 2002 at a tertiary care hospital were retrospectively reviewed from a division database. Patients with elective open abdominal aortic aneurysm (AAA) repair during the same period were reviewed to determine those unsuitable for EVAR. Hostile neck anatomy, assessed by computer tomography (CT) scans and angiograms, was defined as one or more of the following: (1) neck length </=10 mm, (2) focal bulge in the neck >3 mm, (3) >2-mm reverse taper within 1 cm below the renal arteries, (4) neck thrombus > or =50% of circumference, and (5) angulation > or =60 degrees within 3 cm below renals. RESULTS Three hundred and twenty-two patients underwent EVAR with an average follow-up of 18 months. Patients in Phase II trials (n = 41), repaired with other graft types (n = 48), or without complete anatomic records (n = 27) were excluded. Demographics and co-morbidities were similar in the 115 good-neck (GN) and 91 bad-neck (BN) patients except for age (mean, 72.9 years GN vs 75.7 BN; P = 0.13), gender (11% female GN vs 22% BN; P =.04); neck length (mean, 21.8 mm GN vs 14.4 mm BN: P <.001), and angulation (mean, 22 degrees GN vs 40 degrees BN; (P <.001). Perioperative mortality (0 GN vs 1.1% BN), late mortality (5.2% GN vs 4.4% BN), all endoleaks (19.1% GN vs 17.6% BN), proximal endoleaks (0.8% GN vs 2.1% BN), and graft migration (0 for both groups) did not reach statistical significance. Neck anatomy precluded EVAR in 106 of 165 (64%) patients with open AAA. CONCLUSIONS Unsupported endografts with active fixation can yield excellent results in treating many medically compromised patients with hostile neck anatomy. Nonetheless, an unsuitable neck remains the most frequent cause for open abdominal AAA.

Treatment strategies of arterial steal after arteriovenous access

INTRODUCTION Ischemic steal syndrome (ISS) associated with arteriovenous (AV) access is rare but can result in severe complications. Multiple techniques have been described to treat ISS with varying degrees of success. This study compares the management and success associated with these techniques. METHODS Patients with ISS between June 2003 and June of 2008 at the University of Pittsburgh Medical Center were retrospectively reviewed. Demographics, type of AV access, management technique, and success of intervention were recorded. Success was defined as resolution of ISS symptoms while preserving access function. One hundred consecutive AV access procedures were reviewed for comparison. Data were analyzed using χ(2) test, Fishers exact test, and Students t test. The study was approved by our institutional review board. RESULTS A total of 114 patients with ISS had a mean age of 65 years (range, 20-90 years), were predominantly female (66%), diabetic (61%), and with a brachial origin fistula (69%). Risk factors for ISS included coronary artery disease (CAD; P < .001), hypertension (P < .001), and tobacco use (P = .048). Women were noted to have a brachial origin access more frequently than men (odds ratio [OR], 3.1; P = .009). Forty-four patients with mild steal were observed. Seventy patients underwent 87 procedures. Procedures performed included ligation (n = 27), banding (n = 22), distal revascularization and interval ligation (DRIL; n = 21), improvement of proximal inflow (n = 9), revision using distal inflow (RUDI; n = 4), and proximalization of arterial inflow (PAI; n = 3). Early procedures (<30 days from the index fistula) were mostly ligation (50%) or banding (38%), while DRIL was the most frequent choice for late interventions (41%). Banding had a high failure rate (62%) and was the most common reason for reintervention (8 of 11, 73%) and DRIL had a better success rate than banding (P ≤ .05). In our current practice, 18% of patients had an AV fistula with the proximal radial artery (PRA) as the inflow source, while this type of fistula accounted for only 2% of all ISS patients. Ligation resolved symptoms in all patients, but the AV access was lost. CONCLUSIONS Risk factors for development of ISS include CAD, diabetes, female gender, hypertension, and tobacco use. Among various options to treat ISS, banding has a low success rate and high likelihood for reintervention, while DRIL is particularly effective although not uniformly. Less invasive treatment options such as RUDI and PAI may be quite effective in treating ISS. Use of the PRA as the inflow source may decrease the incidence of ISS.

Management and outcomes of dialysis access-associated steal syndrome

OBJECTIVE Dialysis access-associated steal syndrome (DASS) complicates arteriovenous access surgery. We describe a 10-year experience with the surgical management of DASS. METHODS DASS operations were retrospectively reviewed from July 2003 to July 2013 from a single academic institution. Demographics, symptoms, surgical details, and outcomes were collected. RESULTS A total of 201 patients had 218 episodes of DASS. Mean age was 65 years, and 62% were women. DASS was caused by 175 arteriovenous fistulas (80%), 41 upper extremity prosthetic grafts (19%), and two thigh grafts (1%); 87% were brachial artery based. A portion (22%) were referred for DASS from outside practices. All patients had grade 2 (48%) or grade 3 (52%) DASS; 92% (185) were available for follow-up, with a median time to first follow-up of 23 days. Surgical procedures included ligation (73), distal revascularization with interval ligation (DRIL) (59), revision using distal inflow (RUDI) (21), banding (38), proximalization of arterial inflow (12), and distal radial artery ligation (13). There were no differences in preoperative comorbidities between treatment groups. The 30-day complications included continued steal, thrombosis, bleeding, infection, and mortality. Ligation and DRIL were performed most often for grade 3 steal. Ligation and banding were performed most acutely (median time to intervention after access creation of 39 and 24 days vs DRIL and RUDI at 97 and 100 days). Fistula preservation was 0% for ligation, 100% for DRIL, 95% for RUDI, and 89% for banding (P < .01). Improvement of symptoms ranged from 75% (banding) to 98% (DRIL) (P = .005). Women were less likely to have DRIL but more likely to have ligation (P = .001). Complications were highest in the banding (49%) and RUDI (37%) groups. Average mortality was 3.5%, with no significant differences among groups. During the study period, 3287 access procedures were performed, and access volume steadily increased (2003-2008, 1312 access creations; 2008-2013, 1975). Percentage of fistulas (79% vs 86%), incidence of steal (4% vs 6%), and percentage of DRILs (25% vs 28%) were consistent across the two study periods. CONCLUSIONS DRIL and ligation were performed in patients with the most severe symptoms. Compared with ligation, DRIL has equal symptom resolution, no increase in complications, and fistula preservation. Compared with banding, DRIL resulted in superior fistula preservation and fewer complications. DRIL should be considered the preferred procedure for management of DASS in patients with a functioning autologous fistula who can tolerate a major operation.

Isolated femoral endarterectomy: Impact of SFA TASC classification on recurrence of symptoms and need for additional intervention

OBJECTIVES Atherosclerotic occlusive disease of the femoral artery is associated with symptoms ranging from claudication to tissue loss. This study examined the clinical and hemodynamic outcomes of isolated femoral endarterectomy (FEA) as well as the predictors of symptom recurrence and need for further intervention. METHODS Patients who underwent an isolated FEA between January 2001 and June 2008 were reviewed. Concurrent superficial femoral artery (SFA) disease was classified into Trans Atlantic Inter-Societal Consensus (TASC) II categories based upon angiographic findings. Hemodynamic success (HS) was defined as a postoperative ankle-brachial index (ABI) increase of >or=0.15. Clinical improvement was classified by Rutherford criteria. Multivariate analysis was used to identify predictors of clinical failure and need for additional intervention (AI). Kaplan-Meier estimates were used to determine the likelihood of both over time. RESULTS Ninety-five patients (105 limbs) with a mean age of 68.3 +/- 10.2 years were reviewed. Indications were severe claudication in 68 (64.8%) limbs and critical limb ischemia (CLI) in 37 (35.2%). Mean preprocedural ABI was 0.57 +/- 0.25. The SFA-popliteal segment was classified as: normal in 34% of limbs, TASC A 23%, B 19%, C 9%, and D in 15%. One fatal myocardial infarction accounted for a procedural mortality of 0.95%. Morbidity was 6.7% (four hematomas and three wound infections) and mean hospital stay was 2.5 +/- 3.1 days. Patency was 100% with a mean follow-up of 11 months (1-72). Complete resolution of symptoms was noted in 73.4% with some clinical improvement noted in 91% of limbs. HS was achieved in 85.1% with a mean ABI increase of 0.27 +/- 0.20, and this correlated with >or=2 runoff vessels (odds ratio [OR] 0.20; 95% confidence interval [CI] 0.04-0.96; P = .045). Kaplan-Meier estimates revealed that 83.8% of patients with marked initial clinical improvement remained symptom free at 2 years, whereas only 28.6% in the group with mild and moderate initial response maintained their clinical status. Freedom from AI at 2 years was 61.8%. Multivariate analysis revealed that TASC C and D lesions (OR 9.3 [2.43-35.63] P = .001) and diabetes (OR 3.64 [1.01-13.15] P = .048) were predictive of recurrent symptoms while extensive endarterectomy and >or=2 vessel tibial runoff decreased the need for AI. CONCLUSION FEA can achieve excellent immediate clinical and hemodynamic outcome in patients with claudication and CLI; however, patients with diabetes and femoropopliteal TASC C and D lesions are likely to experience recurrent symptoms. Long-term symptomatic improvement is associated with the degree of immediate clinical success as well as the status of the run-off vessels. Limited FEA and poor tibial runoff are associated with the need for AI.

Physiologic coarctation of the aorta resulting from proximal protrusion of thoracic aortic stent grafts into the arch

Graft collapse is a known complication of thoracic aortic stent grafting, particularly in cases of traumatic thoracic aortic transection, when a typically smaller diameter aorta is repaired with a relatively large diameter device. In contrast, obstruction of the aorta from a stent graft that protrudes into the aortic arch but does not collapse is a less common complication of thoracic aortic stent grafting that can present as a functional aortic coarctation. We describe here two cases of physiologic coarctation of the aorta caused by stent graft protrusion into the arch that were successfully treated with stent graft explantation and open aortic reconstruction.

Projection MR imaging of peripheral arterial calcifications

Both CT and MR angiography are accurate for the evaluation of luminal abnormalities in peripheral arterial disease (PAD). However, only CT (requiring exposure to potentially hazardous ionizing radiation) provides a reliable means to detect vascular calcifications. In this study, we demonstrate the feasibility of detecting peripheral arterial calcifications with MRI.

Persistent sciatic artery aneurysm treated with concomitant tibial bypass and vascular plug embolization

The presence of a persistent sciatic artery is a rare congenital vascular malformation. Complications associated with aneurysmal degeneration of this aberrant vessel include rupture, thrombosis, and embolization with obliteration of outflow vessels. We describe the case of an 82-year-old female presenting with critical limb ischemia due to embolization from a partially thrombosed persistent sciatic artery aneurysm. Successful treatment was achieved via a common femoral to posterior tibial artery bypass with the great saphenous vein and vascular plug embolization of the aneurysm.

Can Computed Tomography Scan Findings Predict “Impending” Aneurysm Rupture?

Several findings on computed tomography (CT) scans of intact aneurysms have been taken to suggest “imminent” or “impending” aneurysm rupture. Often these are identified incidentally in asymptomatic patients when an urgent operation was not planned and may even be ill advised. The authors evaluated whether these signs can truly predict short-term aneurysm rupture. A computerized medical archival system was reviewed from August 1994 to August 2004. Patients with aortic aneurysms and official CT scan reports of “impending rupture” were reviewed. CT films and reports were reviewed for aneurysm characteristics, while computerized medical records were reviewed for patient demographics, comorbidities, symptoms, documented subsequent rupture, and operative findings. Signs of “impending rupture” included the crescent sign, discontinuous circumaortic calcification, aortic bulges or blebs, aortic draping, and aortic wall irregularity. Rupture occurring within 2 weeks of the index CT was defined as supporting the “imminent” label. Forty-five patients with aortic aneurysms and CT stigmata of “impending rupture” were identified. Five patients with additional signs of suspicious leak and 1 with an infected previously repaired aneurysm were excluded. Of 39 intact aneurysms, 26 (67%) were infrarenal, 2 (5%) were suprarenal, and the remaining 11 (28%) were thoracoabdominal. The patient group had more women than expected (19/39, 49%) and larger aneurysms (mean diameter, 6.8 ±1.4 cm). Mean age was 74 years. Ten patients underwent elective repair within the first 2 weeks after the index CT scan (mean, 4 days), precluding adequate observation for early rupture. None had intraoperative signs of rupture. Early rupture: 2 of the 29 remaining patients ruptured within 72 hours of the CT scan, for a positive predictive value of 6.9%. One additional patient ruptured 7 months later after declining an early intervention. No Rupture: 26 patients were observed an average of 246 days (range, 14 days to 3 years) without evidence of rupture. Fourteen were repaired electively 2 weeks to 3 years after the index CT scan, and 12 never underwent repair, mostly because of severe associated comorbidities, and were observed a mean of 394 days without rupture. Although they should be taken seriously, CT signs of “impending rupture” alone are poor predictors of short-term aortic aneurysm rupture, and alternative terminology is needed until better predictors can be identified.

Endovascular Treatment of Iatrogenic Injury to the Retrohepatic Inferior Vena Cava

Iatrogenic injury of the inferior vena cava (IVC) is a rare event with potentially devastating sequelae. Only a handful of case reports are available in the literature describing successful endovascular techniques to manage this complication. We present the case of a patient with injury to the retrohepatic IVC resulting in life-threatening hemorrhage which was controlled with endovascular stent grafts.

Embolization of Onyx Causing Acute Limb Ischemia

We present the case of a patient with a refractory type II endoleak treated with translumbar Onyx with passage of the Onyx material into the endograft and subsequent embolization to the infrainguinal vasculature. This report represents a new complication of Onyx embolization that, to our knowledge, has not previously been described in the literature.