Potential of mesenchymal stem cell in stabilization of abdominal aortic aneurysm sac.

BACKGROUND: In their origin, abdominal aortic aneurysms (AAAs) are related to an inflammatory reaction within the aortic wall, which can lead to weakness and degeneration of this structure. One of the most widely accepted treatment modalities for AAAs is the placement of stent grafts. Nevertheless, in some patients blood re-enters the aneurysm sac, creating so-called leaks, which constitute a renewed risk of rupture and death.This study explores the possibility of filling aneurysm sacs treated by endovascular aneurysm repair with adipose tissue-derived mesenchymal stem cells (ASCs) in a porcine model. METHODS: We developed a porcine model using 22 animals by creating an artificial AAA made with a Dacron patch. AAAs were then treated with a coated stent that isolated the aneurysm sac, after which we introduced allogeneic ASC into the sac. Animals were followed-up for up to 3 mo. The experiment consisted of the aforementioned surgical procedure performed first, followed by computed tomography and echo-Doppler imaging during the follow-up, and finally, after sacrificing the animals, histologic analysis of tissue samples from the site of cell implantation by a blinded observer and the detection of implanted cells by immunofluorescence detection of the Y chromosome. RESULTS: Our findings demonstrate the survival of ASCs over the 3 mo after implantation and histologic changes associated with this treatment. Treated animals had less acute and chronic inflammation throughout the study period, and we observed increasing fibrosis of the aneurysm sac, no accumulation of calcium, and a regeneration of elastic fibers in the artery. CONCLUSIONS: The combination of endovascular aneurysm repair and cell therapy on AAAs has promising results for the stabilization of the sac, resulting in the generation of living tissue that can secure the stent graft and even showing some signs of wall regeneration. The therapeutic value of such cell-based therapy will require further investigation.

Use of platelet-rich plasma in the healing of chronic ulcers of the lower extremity.

INTRODUCTION AND OBJECTIVES: Platelet-rich plasma (PRP) is used as an adjuvant in the treatment of chronic ulcers of the lower extremity and has shown particularly promising results in the case of neuropathic ulcers. There has been less research, however, into its use in venous and hypertensive ulcers. Our aim was to assess the safety and feasibility of using PRP in the treatment of chronic ulcers of the lower extremity and to evaluate its potential benefits in directed healing. MATERIAL AND METHODS: We prospectively selected 11 patients with nonischemic ulcers of the lower extremity that had been present for at least 6 weeks. PRP was injected subcutaneously into the perilesional tissue and applied topically in 4 sessions held at 1-week intervals. We assessed quality of life (SF-12 questionnaire), pain (visual analog scale), and the circumference of the ulcer before and after treatment. RESULTS: There was a predominance of women (8/11, 73%), and venous ulcers (7/11, 64%) were more common than hypertensive ulcers (4/11, 36%). The median age of the patients was 79 years and the median time since onset of the ulcer was 17 months (range, 6-108 months). We observed a significant reduction in pain (P<.05) and a significant improvement in the physical and mental components of the SF-12 (P<.05). The mean reduction in ulcer size was 60%, and complete healing was achieved in 5 cases. No adverse effects were observed. CONCLUSION: The local application of PRP is a valuable and practical procedure that promotes the healing of chronic ulcers of the lower extremity; it can improve patient quality of life and is particularly effective in local pain relief.

Acute iliac artery thrombosis and pulsatile femoral and popliteal veins in the same extremity: a case report.

Systemic venous pressure is elevated in right heart failure, and this elevation may be reflected in pulsatile venous flow when there is significant tricuspid regurgitation. The presence of this systolic reversed flow in the femoral and popliteal veins may result in major difficulties for diagnosis and treatment. We report the case of a patient with signs and symptoms of acute ischemia of the right lower limb with palpable pulse in the groin and popliteal fossa. Tricuspid regurgitation was suspected by clinical examination, and Doppler ultrasonographic examination of the extremity revealed pulsatile flow in the femoral and popliteal veins while the iliac arterial axis was occluded. A preoperative angiogram revealed an underlying iliac artery thrombosis, which was successfully treated.

Aortoenteric fistula arising as a complication of endovascular treatment of abdominal aortic aneurysm.

Estimates of the incidence of aortoenteric fistula as a sequela of surgery of the aorta range 1-2%. This complication is less common in patients who have had an aortic endograft implanted for aortoiliac aneurysm. We present three cases of aortoenteric fistula complicating endovascular treatment of abdominal aortic aneurysm (3/423 patients, 0.7% in our series).

Combined surgical and endovascular repair of a ruptured bilateral aortoiliac aneurysm.

Aortoiliac aneurysms are frequent entities that have very important clinical implications, especially in the younger patients. We are asked not only to save lives by preventing the rupture or repairing those that are already ruptured but also to provide an acceptable quality of life in the postoperative period. Endovascular approaches certainly give us such an expectative but are not clearly indicated in our younger patients and cannot be used routinely in those aneurysms with a yuxtarrenal origin. This is the case report of a young man with a yuxtarrenal aortoiliac inflammatory aneurysm that was treated by the interposition of an aortobifemoral bypass with the addition of endovascular devices in the hypogastric vessels to preserve the pelvic blood flow; they contribute to seal the common iliac aneurysms. This approach was useful to avoid complications during a difficult iliac dissection and was permeable within 1 year of the operation. Durability must be assessed.

[Treatment of an abdominal aorta aneurysms with endovascular stent grafts and embolizing materials: an experimental study]. / Tratamiento de un aneurisma de aorta abdominal con prótesis endovascular y materiales embolizantes: estudio experimental.

OBJECTIVE: To create an animal model to stabilize the aneurysmal sac and prevent type II leaks in the endovascular treatment of aneurysms of the abdominal aorta (AAA) by placing an endoprosthesis (stent-graft) and filling the aneurysmal sac. MATERIAL AND METHODS: AAA were experimentally induced in pigs and sheep; AAA were subsequently treated with endovascular stent grafts and stabilized in the same procedure by introducing ethibloc and onyx through a vascular catheter placed within the aneurysmal sac. All animals underwent aortography, and MR angiography and abdominal CT were performed on randomly selected animals. Histological studies included both macroscopic and microscopic examination. Two sheep were analyzed one year after the procedure. We evaluated the characteristics of the materials employed, their diffusion in the collateral arteries, and their efficacy in stabilizing the aneurysmal sac. RESULTS: The procedure was successfully carried out in all animals. Survival in the pigs was 100 %, whereas greater instability under anesthesia in the sheep led to 50 % perioperative mortality. Both ethibloc and onyx were considered easy to use and stable over time. CONCLUSION: The sac of an AAA treated with an endovascular stent graft and its collateral vessels can be treated in the same procedure with materials introduced through a catheter.