Matthew R. Smeds

The contemporary management of renal artery aneurysms

BACKGROUND Renal artery aneurysms (RAAs) are rare, with little known about their natural history and growth rate or their optimal management. The specific objectives of this study were to (1) define the clinical features of RAAs, including the precise growth rate and risk of rupture, (2) examine the current management and outcomes of RAA treatment using existing guidelines, and (3) examine the appropriateness of current criteria for repair of asymptomatic RAAs. METHODS A standardized, multi-institutional approach was used to evaluate patients with RAAs at institutions from all regions of the United States. Patient demographics, aneurysm characteristics, aneurysm imaging, conservative and operative management, postoperative complications, and follow-up data were collected. RESULTS A total of 865 RAAs in 760 patients were identified at 16 institutions. Of these, 75% were asymptomatic; symptomatic patients had difficult-to-control hypertension (10%), flank pain (6%), hematuria (4%), and abdominal pain (2%). The RAAs had a mean maximum diameter of 1.5 ± 0.1 cm. Most were unilateral (96%), on the right side (61%), saccular (87%), and calcified (56%). Elective repair was performed in 213 patients with 241 RAAs, usually for symptoms or size >2 cm; the remaining 547 patients with 624 RAAs were observed. Major operative complications occurred in 10%, including multisystem organ failure, myocardial infarction, and renal failure requiring dialysis. RAA repair for difficult-to-control hypertension cured 32% of patients and improved it in 26%. Three patients had ruptured RAA; all were transferred from other hospitals and underwent emergency repair, with no deaths. Conservatively treated patients were monitored for a mean of 49 months, with no acute complications. Aneurysm growth rate was 0.086 cm/y, with no difference between calcified and noncalcified aneurysms. CONCLUSIONS This large, contemporary, multi-institutional study demonstrated that asymptomatic RAAs rarely rupture (even when >2 cm), growth rate is 0.086 ± 0.08 cm/y, and calcification does not protect against enlargement. RAA open repair is associated with significant minor morbidity, but rarely a major morbidity or mortality. Aneurysm repair cured or improved hypertension in >50% of patients whose RAA was identified during the workup for difficult-to-control hypertension.

Endovascular Repair of a Para-Anastomotic Pseudoaneurysm After Renal Autotransplantation: An Alternative to Open Reconstruction

Renal artery anastomotic pseudoaneurysms are rare after renal transplantation. The etiology tends to be technical, infectious, or degenerative, and repair is difficult with a high postsurgical complication rate. We report the first case of a complex autotransplant renal artery pseudoaneurysm repaired with kissing covered stents. A 52-year-old woman presented with severe left lower quadrant abdominal pain 6 years after a renal autotransplant for ureteral stenosis and recurrent pyelonephritis. A computed tomographic angiography (CTA) scan revealed a bilobed aneurysm arising at the anastomosis between the renal and common iliac arteries. Kissing covered stents were placed within the common iliac artery proximally and extending into the transplant renal artery and external iliac artery. Postdeployment angiography confirmed complete exclusion of the pseudoaneurysm and excellent flow into the transplant kidney and left lower extremity. A follow-up CTA scan at 1 month revealed continued stent-graft patency and complete exclusion of the pseudoaneurysm. An endovascular approach to transplant anastomotic pseduoaneurysms using kissing covered stents is a viable option to exclude aneurysmal changes and preserve flow to the transplanted organ in carefully selected patients.

A multi-institutional experience in adventitial cystic disease.

Background: Adventitial cystic disease (ACD) is an unusual arteriopathy; case reports and small series constitute the available literature regarding treatment. We sought to examine the presentation, contemporary management, and long‐term outcomes using a multi‐institutional database. Methods: Using a standardized database, 14 institutions retrospectively collected demographics, comorbidities, presentation/symptoms, imaging, treatment, and follow‐up data on consecutive patients treated for ACD during a 10‐year period, using Society for Vascular Surgery reporting standards for limb ischemia. Univariate and multivariate analyses were performed comparing treatment methods and factors associated with recurrent intervention. Life‐table analysis was performed to estimate the freedom from reintervention in comparing the various treatment modalities. Results: Forty‐seven patients (32 men, 15 women; mean age, 43 years) were identified with ACD involving the popliteal artery (n = 41), radial artery (n = 3), superficial/common femoral artery (n = 2), and common femoral vein (n = 1). Lower extremity claudication was seen in 93% of ACD of the leg arteries, whereas patients with upper extremity ACD had hand or arm pain. Preoperative diagnosis was made in 88% of patients, primarily using cross‐sectional imaging of the lower extremity; mean lower extremity ankle‐brachial index was 0.71 in the affected limb. Forty‐one patients with lower extremity ACD underwent operative repair (resection with interposition graft, 21 patients; cyst resection, 13 patients; cyst resection with bypass graft, 5 patients; cyst resection with patch, 2 patients). Two patients with upper extremity ACD underwent cyst drainage without resection or arterial reconstruction. Complications, including graft infection, thrombosis, hematoma, and wound dehiscence, occurred in 12% of patients. Mean lower extremity ankle‐brachial index at 3 months postoperatively improved to 1.07 (P < .001), with an overall mean follow‐up of 20 months (range, 0.33‐9 years). Eight patients (18%) with lower extremity arterial ACD required reintervention (redo cyst resection, one; thrombectomy, three; redo bypass, one; balloon angioplasty, three) after a mean of 70 days with symptom relief in 88%. Lower extremity patients who underwent cyst resection and interposition or bypass graft were less likely to require reintervention (P = .04). One patient with lower extremity ACD required an above‐knee amputation for extensive tissue loss. Conclusions: This multi‐institutional, contemporary experience of ACD examines the treatment and outcomes of ACD. The majority of patients can be identified preoperatively; surgical repair, consisting of cyst excision with arterial reconstruction or bypass alone, provides the best long‐term symptomatic relief and reduced need for intervention to maintain patency.

New predictors of complications in carotid body tumor resection

Objective: This study examined the relationship between two new variables, tumor distance to base of skull (DTBOS) and tumor volume, with complications of carotid body tumor (CBT) resection, including bleeding and cranial nerve injury. Methods: Patients who underwent CBT resection between 2004 and 2014 were studied using a standardized, multi‐institutional database. Demographic, perioperative, and outcomes data were collected. CBT measurements were determined from computed tomography, magnetic resonance imaging, and ultrasound examination. Results: There were 356 CBTs resected in 332 patients (mean age, 51 years; 72% female); 32% were classified as Shamblin I, 43% as Shamblin II, and 23% as Shamblin III. The mean DTBOS was 3.3 cm (standard deviation [SD], 2.1; range, 0‐10), and the mean tumor volume was 209.7 cm3 (SD, 266.7; range, 1.1‐1642.0 cm3). The mean estimated blood loss (EBL) was 257 mL (SD, 426; range, 0‐3500 mL). Twenty‐four percent of patients had cranial nerve injuries. The most common cranial nerves injured were the hypoglossal (10%), vagus (11%), and superior laryngeal (5%) nerves. Both Shamblin grade and DTBOS were statistically significantly correlated with EBL of surgery and cranial nerve injuries, whereas tumor volume was statistically significantly correlated with EBL. The logistic model for predicting blood loss and cranial nerve injury with all three variables—Shamblin, DTBOS, and volume (R2 = 0.171, 0.221, respectively)—was superior to a model with Shamblin alone (R2 = 0.043, 0.091, respectively). After adjusting for Shamblin grade and volume, every 1‐cm decrease in DTBOS was associated with 1.8 times increase in risk of >250 mL of blood loss (95% confidence interval, 1.25‐2.55) and 1.5 times increased risk of cranial nerve injury (95% confidence interval, 1.19‐1.92). Conclusions: This large study of CBTs demonstrates the value of preoperatively determining tumor dimensions and how far the tumor is located from the base of the skull. DTBOS and tumor volume, when used in combination with the Shamblin grade, better predict bleeding and cranial nerve injury risk. Furthermore, surgical resection before expansion toward the base of the skull reduces complications as every 1‐cm decrease in the distance to the skull base results in 1.8 times increase in >250 mL of blood loss and 1.5 times increased risk of cranial nerve injury.

Unilateral inline replacement of infected aortofemoral graft limb with femoral vein

Objective: Aortic graft infection remains a formidable challenge for the vascular surgeon. Traditionally, reconstruction with a neoaortoiliac system (NAIS) involves removal of the entire synthetic graft with in situ reconstruction using femoral vein. Whereas the NAIS procedure is durable with excellent graft patency and a low reinfection rate, it can take up to 10 hours and result in a high perioperative complication rate with significant mortality. Not infrequently, the infection is limited to a single limb. In addition, the patient may be too frail to tolerate aortic clamping for a complete graft excision. Under such circumstances, complete excision of the aortofemoral bypass graft (AFBG) may not be indicated. It is hypothesized that local control of infection and limited reconstruction using femoral vein may be acceptable. The objective of this study was to examine the outcomes of all patients who underwent partial AFBG resection and in situ reconstruction with femoral vein. Methods: A retrospective review of all AFBG infections from 2003 to 2015 treated at a tertiary care facility was undertaken. Patients who underwent unilateral partial graft excision with inline reconstruction using femoral vein at the distal (femoral) anastomosis were included. Complete excisions with bilateral revascularizations using any conduit or any extra‐anatomic reconstructions were excluded. The primary end point was successful treatment of infection. Secondary end points were procedure‐related mortality, graft patency, and perioperative complications. Results: During a 12‐year period, partial graft excision with bypass using the femoral vein was performed in 21 patients (24 limbs). Mean age was 61 ± 12 years. There were 13 men and 8 women. Mean follow‐up was 53 ± 27 months. Successful treatment was achieved in 19 of 21 patients. The two treatment failures were due to persistent infection. One of these patients declined complete graft excision and is receiving lifelong suppressive antibiotic therapy. The other patient underwent complete graft excision and an NAIS reconstruction. There were no perioperative or procedure‐related deaths. There were no major amputations, and primary graft patency was 92% at 72 months. The most common AFBG culture isolate was Staphylococcus species. Approximately one‐third of cultures did not yield any growth. Patients underwent anywhere from 1 to 12 weeks of combined intravenous and oral antibiotic therapy. Conclusions: This limited series demonstrates excellent graft patency with a low persistent infection rate. Thus, in patients with localized graft infection, partial excision with preservation of the proximal synthetic graft is an acceptable alternative when patient factors preclude complete graft excision.

Delayed management of Grade III blunt aortic injury: Series from a Level I trauma center.

BACKGROUND Blunt aortic injuries (BAIs) are traditionally treated as surgical emergencies, with the majority of repairs performed in an urgent fashion within 24 hours, irrespective of the grade of aortic injury. These patients are often underresuscitated and often have multiple other trauma issues that need to be addressed. This study reviews a single centers experience comparing urgent (<24 hours) thoracic endovascular aneurysm repair (TEVAR) versus delayed (>24 hours) TEVAR for Grade III BAI. METHODS All patients undergoing TEVAR for BAI at a single institution between March 2004 and March 2014 were reviewed (n = 43). Patients with Grade I, II, or IV aortic injuries as well as those who were repaired with an open procedure or who lacked preoperative imaging were excluded from the analysis. Demographics, intraoperative data, postoperative survival, and complications were compared. RESULTS During this period, there were 43 patients with blunt thoracic aortic injury. There were 29 patients with Grade III or higher aortic injuries. Of these 29 patients, 1 declined surgery, 2 were repaired with an open procedure, 10 underwent urgent TEVAR, and 16 had initial observation. Of these 16, 13 underwent TEVAR in a delayed fashion (median, 9 days; range, 2–91 days), and 3 died of non–aortic-related pathology. Comparing the immediate repair group versus the delayed repair group, there were no significant demographic differences. Trauma classification scores were similar, although patients in the delayed group had a higher number of nonaortic injuries. The 30-day survival was similar between the two groups (9 of 10 vs. 12 of 16), with no mortalities caused by aortic pathology in either group. CONCLUSION Watchful waiting may be permissible in patients with Grade III BAI with other associated multisystem trauma. This allows for a repair in a more controlled environment. LEVEL OF EVIDENCE Therapeutic study, level V.

Outcomes after Arterial Endovascular Procedures Performed in Patients with an Elevated International Normalized Ratio

BACKGROUND Patients treated with anticoagulants frequently require urgent vascular procedures and elevated prothrombin time/international normalized ratio (INR) is traditionally thought to increase access site bleeding complications after sheath removal. We aimed to determine the safety of percutaneous arterial procedures on patients with a high INR in the era of modern ultrasound-guided access and closure device use. METHODS Patients undergoing arterial endovascular procedures at a single institution between October 2010 and November 2012 were reviewed (n = 1,333). We retrospectively analyzed all patients with an INR > 1.5. Venous procedures, lysis checks, and cases with no documented INR within 24 hr were excluded. Sixty-five patients with 91 punctures were identified. A comparison group was then generated from the last 91 patients intervened on with INR < 1.6. Demographics, intraoperative data, and postoperative complications were compared. RESULTS The demographics were similar. More Coumadin use and higher INR were found in the study group (71/91 and 0/91, P = 0.001; 2.3 and 1.1 sec, P = 0.001, respectively), but there was more antiplatelet use in the control group (68/91 and 51/91, P = 0.01). Intraoperatively, the sheath sizes, protamine use, closure device use, ultrasound guidance, brachial access, and procedure types were not statistically different. Sheath sizes ranged from 4 to 22F in the study group and 4 to 20F in the control group. Paradoxically, heparin was administered more frequently in the study group (64/91 and 50/91, P = 0.046). Bleeding complications occurred more commonly in the study group (3/91 and 1/91, P = 0.62), but this failed to reach significance and the overall complication rate in both groups was low. CONCLUSIONS Endovascular procedures may be performed safely with a low risk of bleeding complications in patients with an elevated INR. Ultrasound guidance and closure device use may allow these cases to be performed safely, but a larger series may be needed to confirm this.

Infrarenal endovascular aneurysm repair: New developments and decision making in 2016

New developments in infrarenal abdominal aortic aneurysm stent-graft devices have made more patients eligible for endovascular aneurysm repair (EVAR). Recent US Food and Drug Administration approval for fenestrated endograft repair and impending approval for iliac branch devices extend the proximal and distal landing zones. Better deployment systems allow for partial deployment of endografts to facilitate repositioning, and more flexible designs allow for treatment of angulated infrarenal aneurysm necks and tortuous iliac arteries. New iterations of endografts have smaller delivery catheter diameters, which facilitate traversal of smaller access vessels. Long-term outcomes data are still accumulating and it remains to be seen whether EVAR for this expanded-indication abdominal aortic aneurysms anatomy has the same durability as standard EVAR. More options for repair also mean vascular surgeons must select the best EVAR device based on each patients abdominal aortic aneurysm anatomy.

Suprarenal stent perforation after endovascular abdominal aortic aneurysm repair

A 66-year-old man with an abdominal aortic aneurysm previously repaired with an endovascular stent graft presented to our facility with worsening midabdominal and back pain. Previous postoperative surveillance computed tomography scans were unremarkable, showing excellent stent-wall apposition and a shrinking aneurysm sac; however, imaging done on his arrival identified a contained rupture at the level of the celiac artery containing a perforating suprarenal stent. We repaired this rupture with a surgeon-modified fenestrated stent graft. To our knowledge, this is the first reported case of penetration of the native aorta by a suprarenal stent in the absence of infection or trauma.

Treatment of chronic venous stent occlusion with a Wildcat catheter.

A 47-year-old female with an occluded iliac vein stent originally placed for deep venous thrombosis and May-Thurner syndrome presented to our clinic with complaints of left lower extremity pain and swelling. Multiple previous attempts had been made to cross this lesion with guidewire and catheter techniques without success. We were able to cross the lesion with the Wildcat catheter. Subsequent directional laser atherectomy and balloon angioplasty followed by stent placement resulted in a patent stent and resolution of her symptoms. This is the first reported use of the Wildcat catheter in chronic venous stent occlusions.