Neil Moudgill

Endothelial Differentiation of Adipose-Derived Stem Cells from Elderly Patients with Cardiovascular Disease

Adipose-derived stem cells (ASCs) possess significant therapeutic potential for tissue engineering and regeneration. This study investigates the endothelial differentiation and functional capacity of ASCs isolated from elderly patients. Isolation of ASCs from 53 patients (50-89 years) revealed that advanced age or comorbidity did not negatively impact stem cell harvest; rather, higher numbers were observed in older donors (>70 years) than in younger. ASCs cultured in endothelial growth medium-2 for up to 3 weeks formed cords upon Matrigel and demonstrated acetylated-low-density lipoprotein and lectin uptake. Further stimulation with vascular endothelial growth factor and shear stress upregulated endothelial cell-specific markers (CD31, von Willebrand factor, endothelial nitric oxide synthase, and VE-cadherin). Inhibition of the PI(3)K but not mitogen-activated protein kinase pathway blocked the observed endothelial differentiation. Shear stress promoted an anti-thrombogenic phenotype as demonstrated by production of tissue-plasminogen activator and nitric oxide, and inhibition of plasminogen activator inhibitor-1. Shear stress augmented integrin α(5)β(1) expression and subsequently increased attachment of differentiated ASCs to basement membrane components. Finally, ASCs seeded onto a decellularized vein graft resisted detachment despite application of shear force up to 9 dynes. These results suggest that (1) advanced age and comorbidity do not negatively impact isolation of ASCs, and (2) these stem cells retain significant capacity to acquire key endothelial cell traits throughout life. As such, adipose tissue is a practical source of autologous stem cells for vascular tissue engineering.

May-Thurner syndrome: case report and review of the literature involving modern endovascular therapy.

May-Thurner syndrome is a rare clinical entity involving venous obstruction of the left lower extremity. Obstruction occurs secondary to compression of the left common iliac vein between the right common iliac artery and the underlying vertebral body. Current management largely involves endovascular therapy. A review was conducted of six studies containing at least five patients with May-Thurner syndrome treated by endovascular therapy. We compiled data on 113 patients, analyzing patient demographics, treatment details, and outcome. An 18-year-old female presented 1 week after the onset of left lower extremity pain and swelling. Duplex ultrasonography revealed extensive left-sided deep venous thrombosis (DVT). Thrombolysis followed by iliac vein stent placement restored patency to the venous system, with subsequent resolution of symptoms. Review of 113 patients revealed that the majority were females (72%) presenting with DVT (77%), most of which was acute in onset (73%). Therapy consisted of catheter-directed thrombolysis and subsequent stent placement in the majority of patients, resulting in a mean technical success of 95% and a mean 1-year patency of 96%. Endovascular therapy is the current mainstay of treatment for May-Thurner syndrome. Review of the current literature supports treatment via catheter-directed thrombolysis followed by stent placement with good early results.

Robot-assisted minimally invasive esophagectomy is equivalent to thoracoscopic minimally invasive esophagectomy

The use of the surgical robot has been increasing in thoracic surgery. Its three-dimensional view and instruments with surgical wrists may provide advantages over traditional thoracoscopic techniques. Our initial experience with thoracoscopic robot-assisted minimally invasive esophagectomy (RAMIE) for esophageal cancer was compared with our traditional thoracoscopic minimally invasive esophagectomy (MIE) approach for esophageal cancer. A retrospective review of a prospective database was performed. From July 2008 to October 2009, 43 patients underwent MIE resection. Patients who had benign disease and intrathoracic anastomosis were excluded. Results are presented as mean ± SD. Significance was set as P < 0.05. Eleven patients who underwent RAMIE and 26 who underwent MIE were included in the cohort. No differences in age, sex, race, body mass index, or preoperative radiotherapy or chemotherapy between the groups were observed. No significant differences in operative time, blood loss, number of resected lymph nodes, postoperative complications, days of mechanical ventilation, length of intensive care unit stay, or length of hospital stay were also observed. In this short-term study, RAMIE was found to be equivalent to thoracoscopic MIE and did not offer clear advantages.

Results of polytetrafluoroethylene-covered nitinol stents crossing the inguinal ligament

OBJECTIVE Placement of arterial endoprostheses across the inguinal ligament is generally thought to be contraindicated for fear of device kinking, fracture, or occlusion and possible obliteration of the deep femoral artery (DFA). We present a series of selected patients who underwent insertion of polytetrafluoroethylene-covered nitinol stents (Viabahn stent grafts. W. L. Gore and Associates Inc, Flagstaff, Ariz) crossing the middle common femoral artery (CFA) on an emergency basis or who were considered high risk for open surgery. METHODS We treated 16 patients with 17 lesions adjacent to or within the CFA with stent grafts that originated in the common iliac (two) or external iliac (15) artery and terminated in the distal CFA (12), DFA (three), or superficial femoral (two) artery. Stent grafts were placed on an elective (10) or emergency (seven) basis for arterial occlusive disease (10), bleeding (six), and aneurysmal disease (one). Comorbidities favoring endovascular treatment were high medical risk (10) previous scarring (four), morbid obesity (two), and dense arterial calcification precluding open surgical repair (one). RESULTS The DFA was deliberately sacrificed in one of the 17 cases. No patient suffered major complications after the procedure. All grafts remained patent based on duplex ultrasound imaging during follow-up (mean, 12.3 months; range, 1-58 months). Two patients required an additional endovascular intervention to treat inflow or outflow stenoses during follow-up, yielding a 2-year primary patency rate of 93.8% and assisted primary patency rate of 100%. CONCLUSIONS These results suggest that selective placement of Viabahn stent grafts across the inguinal ligament to treat arterial occlusive disease or bleeding may prove to be safe, effective, and associated with acceptable patency rates. This strategy helps avoid complicated open arterial surgery in high-risk patients with associated multiple medical risk factors or hostile scarred groins.

Coil-assisted false lumen thrombosis in complicated chronic type B dissection

Type B dissections complicated by pain, malperfusion, or aneurysm expansion mandate surgical intervention. Success of this therapy is predicated on exclusion and thrombosis of the false lumen of the aneurysm. We report a case where cessation of flow was achieved using covered stent grafts in conjunction with coil embolization of the false lumen. The introduction of coils into the false lumen is a novel approach and may provide a helpful adjunct in endovascular treatment of complicated type B aortic dissections.

Robotic-assisted median arcuate ligament release

Median arcuate ligament syndrome results from external compression of the celiac axis by attachments of the diaphragmatic crura. It has been treated with open or laparoscopic surgical decompression of the celiac axis with neurolysis. We describe our initial experience treating three patients using a robotic-assisted technique with median arcuate ligament release and celiac neurolysis. Average operative time was 2.2 hours. No intraoperative complications occurred. At an average of 11 months postoperative (14, 11, and 8 months), two patients continue with resolution of preoperative symptoms. Our experience affirms that further study using the robotic approach appears warranted.

Arterial protocol including prophylactic distal perfusion catheter decreases limb ischemia complications in patients undergoing extracorporeal membrane oxygenation

Objective: Venoarterial extracorporeal membrane oxygenation (ECMO) is a salvage therapy in patients with severe cardiopulmonary failure. Owing to the large size of the cannulas inserted via the femoral vessels (≤24‐F) required for adequate oxygenation, this procedure could result in significant limb ischemic complications (10%‐70%). This study evaluates the results of a distal limb perfusion arterial protocol designed to reduce associated complications. Methods: We conducted a retrospective institutional review board‐approved review of consecutive patients requiring ECMO via femoral cannulation (July 2010‐January 2015). To prevent arterial ischemia, a distal perfusion catheter (DPC) was placed antegrade into the superficial femoral artery and connected to the ECMO circuit. Limb perfusion was monitored via near‐infrared spectroscopy (NIRS) placed on both calves. Decannulation involved open repair, patch angioplasty, and femoral thrombectomy as needed. Results: A total of 91 patients were placed on ECMO via femoral arterial cannula (16‐F to 24‐F) for a mean duration of 9 days (range, 1–40 days). A percutaneous DPC was inserted prophylactically at the time of cannulation in 55 of 91 patients, without subsequent ischemia. Of the remaining 36 patients without initial DPC placement, 12 (33% without DPC) developed ipsilateral limb ischemia related to arterial insufficiency, as detected by NIRS and clinical findings. In these patients, the placement of a DPC (n = 7) with or without a fasciotomy, or with a fasciotomy alone (n = 4), resulted in limb salvage; only one patient required subsequent amputation. After decannulation (n = 7), no patients had further evidence of limb ischemia. Risk factors for the development of limb ischemia identified by categorical analysis included lack of DPC at time of cannulation and ECMO cannula size of less than 20‐Fr. There was a trend toward younger patient age. Overall ECMO survival rate was 42%, whereas survival in patients with limb ischemia was only 25%. Conclusions: Limb ischemia complications from ECMO may be decreased by prophylactic placement of an antegrade DPC. Without DPC, continuous monitoring using NIRS may identify limb ischemia, which can be treated subsequently with DPC and or fasciotomy.

Hybrid endovascular treatment of an aberrant right subclavian artery with Kommerell aneurysm

Aberrant right subclavian artery is a rare anatomical finding of abnormal embryologic development of the dorsal aorta and right subclavian artery. An associated aortic outpouching, or Kommerell diverticulum, may develop at the origin of the aberrant right subclavian artery. Given historically high rates of aneurysm rupture and mortality, early repair is indicated. Successful aneurysm exclusion can be accomplished with thoracic endovascular stent grafting following open carotid-subclavian bypass, maintaining upper extremities perfusion. Such hybrid techniques offer a decrease in mortality and complication rates. Herein, we describe a successful repair of a symptomatic (dysphagia, weight loss) aberrant right subclavian artery with Kommerell diverticulum using this hybrid open-endovascular approach.

An interesting anatomic variant of inferior vena cava duplication: case report and review of the literature:

Congenital anomalies of the inferior vena cava (IVC) occur in roughly 4% of the population. We report an interesting case of an atypical variant of duplicated IVC. A 20-year-old man presented with orthopedic injuries and intracranial hemorrhage following a motorcycle accident. He was taken to the fluoroscopy suite for IVC filter placement; duplication of the IVC was noted. The right and left iliac veins shared a normal confluence but two IVCs drained independently into renal veins before reuniting into a single structure. Both IVC filters were placed via a single puncture in the groin. We performed a search of the PubMed database using ‘inferior vena cava duplication’ and reviewed common anomalies of the IVC. Several variants of duplicated IVC exist; the most common of which is two distinct IVCs that arise from each iliac vein without a normal confluence. Our patient had a unique anomaly which allowed filter placements from a single puncture.

Coral reef aorta: case report and review of the literature.

Coral reef aorta (CRA) is a rare form of atherosclerosis that affects the paravisceral and pararenal aorta and its branches. Patients typically present with arterial insufficiency of the bowels, kidneys and lower extremities. The current mainstay of treatment is operative, typically involving transaortic endarterectomy. Herein, we describe a 54-year-old woman with incapacitating lower extremity claudication secondary to a paravisceral coral reef atheroma treated successfully with transaortic endarterectomy via a left retroperitoneal approach. In addition, we present a complete review of modern English literature on CRA.