Completed Projects

  • Plenary Podium Presentation 2014 Vascular Annual Meeting:  The Contemporary Guidelines for Asymptomatic Renal Artery Aneurysms Are Too Aggressive: A North American Experience
  • Publication: The contemporary management of renal artery aneurysms (J Vasc Surg 2015;61:978-84.)
    865 RAAs in 760 patients were identified at 16 institutions. This large, contemporary, multi-institutional study demonstrated that asymptomatic RAAs rarely rupture (even when >2 cm), growth rate is 0.086 6 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.
  • Evidence Summary: Renal artery aneurysms (J Vasc Surg 2015;62:779-85.)

Renal artery aneurysms are rare in the general population, although the true incidence and natural history remain elusive. Controversy over criteria for repair persists across decades. Indications for repair presently include aneurysm size >2 cm, female gender within childbearing age, symptoms like pain and hematuria, medically refractory hypertension including that associated with functionally important renal artery stenosis, thromboembolism, dissection, and rupture. Conventional surgical reconstruction options are variable and continue to offer technically sound and durable results. Endovascular therapies with novel devices also offer technical success with few major adverse events, and are increasingly employed as indications for intervention broaden. This review summarizes the accumulated evidence on true renal artery aneurysms with a particular focus on contemporary treatment criteria, natural history, options for repair and outcomes following such.

One hundred fourteen patients at 22 medical centers in 6 countries underwent partial resection of an infected aortic graft. This large multi-center study suggests that patients who have undergone partial resection of infected aortic grafts may be at high risk of death or post-repair infection, especially older patients with abdominal infection not isolated to a single graft limb, or with Candida infection or aortoenteric fistula. Late reinfection correlated strongly with early persistent postoperative infection, raising concern for occult retained infected graft material.

A total of 241 patients at 34 institutions from seven countries presented with aortic graft infection (AGI) during the study period. After complete resection of AGI, perioperative mortality is 16% and median overall survival is 5.8 years. Extra-anatomic bypass is associated with nearly a two and one-half-fold higher reinfection/mortality compared with in-situ bypass. Omental and/or muscle flap coverage of the repair appear protective.

  • Plenary podium presentation 2015 Western Vascular Society Annual Meeting: Distance to the base of skull: A new predictor of complications in carotid body tumor resection.
  • Poster Presentation 2015 Vascular Annual Meeting: Predictors of neurovascular complications in carotid body tumor resection
  • Publication: New predictors of complications in carotid body tumor resection (J Vasc Surg 2017;65:1673-9.)
    356 carotid body tumors were resected in 332 patients. 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
  • Plenary Podium Presentation 2016 Western Vascular Society Annual Meeting: Medical therapy and intervention do not improve uncomplicated isolated mesenteric artery dissection outcomes over observation alone. 
  • Publication: Medical therapy and intervention do not improve uncomplicated isolated mesenteric artery dissection outcomes over observation alone. (J Vasc Surg 2017;66:202-208) (link: https://www.sciencedirect.com/science/article/pii/S0741521417303701?via%3Dihub)
    Twelve institutions identified 227 patients with isolated dissection of the celiac or superior mesenteric artery. Asymptomatic patients with isolated mesenteric artery dissection may be observed and followed up with intermittent imaging. Symptomatic patients tend to have longer dissections than asymptomatic patients. Symptomatic isolated mesenteric artery dissection without evidence of ischemia does not require anticoagulation and may be treated with antiplatelet therapy or observation alone.

Eleven institutions identified 173 individuals with vEDS. This study highlights the importance of confirming vEDS diagnosis by testing for pathogenic COL3A1 variants rather than relying on clinical diagnostic criteria alone given the high degree of overlap with other forms genetically triggered arteriopathies. Because not all COL3A1 variants are pathogenic, the interpretation of the genetic testing results by an individual trained in variant assessment is essential to confirm the diagnosis. An accurate diagnosis is critical and has serious implications for lifelong screening and treatment strategies for the affected individual and family members.

Eleven institutions identified 86 individuals with pathogenic variants in COL3A1. Most of the vEDS arterial manifestations were managed medically in this cohort. When intervention is required for an enlarging aneurysm or rupture, embolization, and less frequently stenting, seem to be well-tolerated. Open repair of abdominal aortic aneurysm seems to be as well-tolerated as in those without vEDS; vEDS should not be a deterrent to offering an operation. Future work to elucidate the role of surgical interventions and refine management recommendations in the context of patient centered outcomes is warranted.

Eight-hundred thirty-two consecutive patients with venous leg ulcers were identified at 11 centers in the United States. This study demonstrates that correction of superficial truncal vein reflux, as well as deep vein stenosis, both contribute to healing of VLU. Patients who fail to heal their VLU after superficial and perforator ablation should have the iliocaval system imaged to identify hemodynamically significant stenoses or occlusions amenable to stenting, which facilitates venous ulcer healing even in patients with large ulcers.

92 patients were treated at 14 institutions for primary leiomyosarcoma with surgical resection and reconstruction. The findings from our multi-institutional study have demonstrated that complete en bloc resection of IVC leiomyosarcoma with vascular surgical reconstruction in selected patients results in low perioperative mortality and is associated with excellent long-term patency. A ringed PTFE graft was the most commonly used conduit for caval reconstruction, yielding excellent long-term primary patency.

A total of 66 extremity aneurysms from 11 institutions were analyzed, 40 of which were in a popliteal location, 14 iliofemoral, and 12 in an upper extremity or a jugular location. Large lower extremity venous aneurysms and saccular aneurysms with thrombus >25% of the lumen are more likely to present with thromboembolic complications. Surgical intervention for lower extremity venous aneurysms is indicated to reduce the risk of venous thromboembolism (VTE) and the need for continued anticoagulation. Popliteal aneurysms >2.5 cm and all iliofemoral aneurysms should be considered for repair. Upper extremity aneurysms do not have a significant risk of VTE and warrant treatment primarily for symptoms other than VTE.

516 patients with celiac artery compression were treated at 24 institutions. No difference was found in long-term failure after open vs laparoscopic MALR; however, open release was associated with higher perioperative morbidity. These results support the use of a preoperative celiac plexus block to aid in patient selection. Operative candidates for MALR should be counseled regarding the factors associated with treatment failure and the relatively high overall rate of treatment failure.

A total of 285 patients were identified at 35 institutions. Treatment of ASA/KD can be performed safely with low rates of mortality, stroke and reintervention and high rates of symptomatic relief, regardless of the repair strategy. Symptomatic and urgent operations were associated with worse outcomes in general, and female gender was associated with a higher likelihood of reintervention. Given the worse overall outcomes when symptomatic and the inherent risk of rupture, consideration of repair at 40 mm is reasonable in most patients. ASA/KD can be repaired in asymptomatic patients with excellent outcomes and young healthy patients may be considered better candidates for open approaches versus endovascular or hybrid modalities, given the lower likelihood of reintervention and lower early mortality rate.

288 patients with aberrant subclavian artery with or without Kommerell’s diverticulum (ASA/KD) were identified; 222 left-sided aortic arch (LAA), and 66 right-sided aortic arch (RAA). In patients with ASA/KD, RAA patients were less common than LAA, presented more frequently with dysphagia, had symptoms as an indication for intervention, and underwent treatment at a younger age. Open, endovascular and hybrid repair approaches appear equally effective, regardless of arch laterality.

Projects in progress

  • Thoracofemoral bypass
  • Nutcracker syndrome

For questions, comments or to join the collaborative, contact us at [email protected].