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Cardiovascular diseases are a major health concern and therefore an important topic in biomedical research. Large animal models allow researchers to assess the safety and efficacy of new cardiovascular procedures in systems that resemble human anatomy; additionally, they can be used to emulate scenarios for training purposes. Among the many biomedical models that are described in published literature, it is important that researchers understand and select those that are best suited to achieve the aims of their research, that facilitate the humane care and management of their research animals and that best promote the high ethical standards required of animal research. In this resource the authors describe some common swine models that can be easily incorporated into regular practices of research and training at biomedical institutions. These models use both native and altered vascular anatomy of swine to carry out research protocols, such as testing biological reactions to implanted materials, surgically creating aneurysms using autologous tissue and inducing myocardial infarction through closed-chest procedures. Such models can also be used for training, where native and altered vascular anatomy allow medical professionals to learn and practice challenging techniques in anatomy that closely simulates human systems.

Ruptured abdominal aortic aneurysm is related with a 100% mortality rate if left untreated. Even with surgical intervention or endovascular repair, mortality is still extremely high. However, there are conditions in which neither open surgical aneurysm repair nor endovascular aneurysm repair can be considered a viable therapeutic option because of comorbidities or anatomic reasons. We report a case of successful endovascular treatment in a patient with ruptured abdominal aortic aneurysm by occluding the abdominal aneurysm using the Amplatzer Vascular Plug (AVP II).

The aim of this study was to evaluate the effectiveness of endovascular repair in the treatment of isolated iliac artery aneurysm (IAA) using Excluder bifurcated endograft. Eight consecutive patients with IAA were treated during a period of 45 months using Excluder bifurcated endograft. Two patients presented with isolated IAA rupture and were treated emergently, whereas the other six patients underwent elective treatment. All aneurysms lacked sufficient proximal necks and therefore were not suitable for tubular-shaped endograft. Follow-up imaging was performed at 1 week, at every 3 months during the first year, semiannually until 2 years, and annually afterward using angio-computed axial tomography and plain films. Technical success was achieved in all patients. No mortality was seen despite two patients having IAA rupture. Follow-up (12 to 60 months) was done in all but one patient. During this period, complications were observed in three patients. One patient developed sexual impotence at 3-month follow up; one patient presented unilateral gluteal claudication after the procedure, which resolved at 3 months; and one patient developed a graft porosity-related endoleak, which was successfully managed with placement of an additional ipsilateral iliac extension. Endovascular treatment of isolated IAA using bifurcated endograft is safe and can be an alternative to surgical treatment. The benefits from decreased morbidity and mortality of endoluminal treatment of isolated IAA using bifurcated endograft outweigh the minor complications associated with this technique, which are mostly related to occlusion of hypogastric arteries.

Persistent primitive hypoglossal artery (PPHA) represents the second most common carotid-vertebrobasilar anastomosis. The association of PPHA with intracranial aneurysms is not unusual. Treatment of aneurysms located on the PPHA itself is challenging due to the increased risk of ischemic complications secondary to the hypoglossal artery often being the sole contributor of flow to the posterior circulation. We report a case of a wide-neck aneurysm in a PPHA successfully treated using a stent-assisted coil embolization technique.

To evaluate the effect of temporary stent placement on the canine prostatic urethra.Retrievable PTFE-covered nitinol stents were placed in the prostatic urethras of 8 beagle dogs under fluoroscopic guidance. Retrograde urethrography was obtained before and after stenting. Retrograde urethrography and endoscopy were performed 1 and 2 months after deployment. The endoscopic degree of hyperplasia was rated on a scale of 0 to 4 (0 = absence, 4 = occlusion). On day 60, stents were removed and urethrography was performed immediately before euthanasia. Pathologic analysis was performed to determine the degree of glandular atrophy, periurethral fibrosis, and urethral dilation.Stent deployment was technically successful in 7 animals, and failed in 1 dog due to a narrow urethral lumen. Complete migration was seen in 2 animals at 1 month, and an additional stent was deployed. On day 30, endoscopy showed slight hyperplasia (grade 1) in 3 animals. On day 60, moderate hyperplasia (grade 2) was evidenced in 4 cases. No impairment of urinary flow was seen during follow-up. Retrieval was technically easy to perform, and was successful in all dogs. The major histologic findings were chronic inflammatory cell infiltrates; prostate glandular atrophy, with a mean value of 1.86 (SD 0.90); periurethral fibrosis, with a mean ratio of 29.37 (SD 10.41); and dilatation of the prostatic urethra, with a mean ratio of 6.75 (SD 3.22).Temporary prostatic stent placement in dogs is safe and feasible, causing marked enlargement of the prostatic urethral lumen. Retrievable covered stents may therefore be an option for bladder outlet obstruction management in men.

Angioplasty has long been used in the treatment of peripheral arterial occlusive disease with variable long-term results. In this case report, we present a patient with marfanoid features and acute ischemia of the lower extremity. Angioplasty provided us with the means of emergently relieving the acute symptoms. The patient was subsequently found on further work-up to have hyperhomocysteinemia (HC) and appropriate medical therapy was initiated. We conclude that angioplasty should be considered in pediatric patients with acute occlusive limb ischemia, providing excellent immediate results to preserve the limb as well as the time to investigate the underlying causes.

Endovascular or surgical treatment of femoropopliteal bypass (FPB) graft occlusion is a safe and effective procedure. However, there are some reports that recommend thrombolysis as an initial therapy [1, 2]. In situ thrombolysis (ITL), with later percutaneous transluminal angioplasty (PTA) of any anastomotic stenoses, is the usual endovascular therapy for this condition [1, 2]. On the other hand, there are cases where ITL, as well as primary stenting, may be contraindicated because of the relative risk of distal embolization [3]. We report a case of acute occlusion of a femoropopliteal prosthetic bypass graft where ITL was contraindicated, which was successfully treated with primary stenting. To our knowledge, this is the first report of primary stenting in acute FPB occlusion.

We report two patients with acutely thrombosed popliteal artery aneurysms that were successfully treated with a combination of thrombolytic therapy and placement of noncovered Wallstents.

To present our experience in the treatment of nasolacrimal occlusion by means of polyurethane stents.Forty polyurethane stents were placed under fluoroscopic guidance in 35 consecutive patients with epiphora due to total or partial obstruction of the nasolacrimal system. The set designed by Song was used in all patients. The procedure was performed by introducing a guidewire through the superior punctum into the canaliculus and advancing it across the obstruction into the inferior meatus of the nasal cavity. After pulling out the guidewire, the stent was advanced in retrograde fashion and released into the sac and the nasolacrimal duct.The technical success rate was 100%. The average time for the procedure was 25 min (range 10-60 min). Immediate complications were: mild pain (n = 5), severe pain (n = 1), minimal epistaxis (n = 7), and moderate epistaxis (n = 1). No major complications occurred. The last clinical control revealed complete resolution of epiphora in 35 eyes and partial resolution in four; one patient did not improve.This technique for treatment of obstruction of the nasolacrimal system is simple and safe, and may obviate the use of more invasive procedures.

Seventy-seven transjugular liver biopsies were performed with a coaxial, spring-loaded, 18-gauge cutting needle, the Biopty gun (Bard Biopsy System, Covington, GA, USA) on consecutive patients between July 1993 and February 1995. Fifty men and 27 women were included in the study; the mean age was 45 years (range 15-69 years). The average number of punctures per patient was 5.2, with a range of 2-9, yielding an average of 4.8 samples per patient (range 1-7). The length of the samples varied from 10 to 22 mm with a constant diameter of 1 mm. The mean time required to complete the procedure was 48 min (43-52 min). Histological diagnoses were obtained in 74 of 77 patients (96%), with non-diagnostic specimens attributed to excessive fragmentation (3 cases). Complications occurred in 10 patients (puncture site hematoma, carotid artery puncture, abdominal pain, vasovagal reaction, hepatic capsule perforation, and hemobilia). The latter two complications were self-limited. In our experience this transjugular hepatic biopsy method is promising for performing biopsies in patients with chronic liver disease, due to its high success rate and low morbidity rate.

Purpose: To present a new intravascular device for the treatment of aorto-iliac aneurysms. Methods: This new device was tested in five dogs with abdominal aortic aneurysm created experimentally by overdilation of a balloon-expandable stent with a 16 or 18 mm wide PTA balloon catheter. The design of the device is based on a self-expanding aortic stent which consists of two stretchable circular frames filled with a textile Dacron mesh membrane that is suspended horizontally into the infrarenal abdominal aorta proximally to the aneurysm. The frames are part of a preshaped double helical structure that is introduced longitudinally through a catheter in a parallel fashion and forming the desired shape at the vessel site to be occluded. Two iliac stent-grafts are introduced in a low-profile status through the membrane sealing the aneurysm sac and holding the stent-grafts in place. After stent-graft expansion, a new bifurcation located more proximally than the natural one is created. The follow-up of the dogs was performed clinically and angiographically, and specimens were evaluated histomorphologically. Results: The membrane device can be introduced through a 9 Fr vascular sheath. Technical success was achieved in four of five dogs. Nine of ten stent-grafts could be fixed securely within the membrane, thus preventing dislocation. Aneurysms were excluded immediately, and blood flow to the external iliac arteries was restored by the stent-grafts. At 6–9 months follow-up of technically successful implanted devices, there were no endoleaks, no migration, no stenoses at contact sites between the implant material and vascular wall, and no stenosis or occlusion of the stent-grafts. At microscopic evaluation, the interspace between the membranes was filled with thrombotic material, thus ensuring exclusion of the aneurysm. Conclusion: This new device was found to be flexible, low profile and useful in excluding abdominal aortic aneurysm in the experimental setting.