In vivo assessment of two endothelialization approaches on bioprosthetic valves for the treatment of chronic deep venous insufficiency.

Chronic deep venous insufficiency is a debilitating disease with limited therapeutic interventions. A bioprosthetic venous valve could not only replace a diseased valve, but has the potential to fully integrate into the patient with a minimally invasive procedure. Previous work with valves constructed from small intestinal submucosa (SIS) showed improvements in patients' symptoms in clinical studies; however, substantial thickening of the implanted valve leaflets also occurred.

Slovenian experience from diagnostic angiography to interventional radiology.

Background: The purpose of writing this article is to document the important events and people in the first 50 years of diagnostic angiography and interventional radiology in Slovenia. During this period not only did the name of the institutions and departments change, but also its governance.

Conclusions: This depicted the important roles different people played at various times in the cardiovascular divisions inside and outside of the diagnostic and interventional radiology.

Iodine based radiopacity of experimental blood clots for testing of mechanical thrombectomy devices.

Background: Barium sulfate powder used for radiopacity of experimental blood clots (EBCs) for testing mechanical thrombectomy devices (MTD) has negative effects on EBCs mechanical properties. In vitro and in vivo exploration was performed to determine if the iodine based contrast medium will have less negative effects on the EBCs than barium.

Materials And Methods: Fresh blood from 2 swine was used to create fibrinogen enhanced and thrombin initiated EBC in tubes.

Double BioDisk: a new bioprosthetic device for transcatheter closure of atrial septal defects - a feasibility study in adult sheep.

Background: To evaluate the long-term effectiveness and safety of a new Double BioDisk (DBD) device for closure of atrial septal defect (ASD). MATERIALS AND METHODS.: ASD was created with transeptal needle (TS) followed by balloon dilatation in 12 sheep weighing 40.

Creation of fibrinogen-enhanced experimental blood clots to evaluate mechanical thrombectomy devices for treatment of acute stroke: an in vitro study.

Purpose: To explore if addition of fibrinogen to the most commonly used experimental blood clot (EBC) model would improve its mechanical properties and histologic structure.

Materials And Methods: Fresh blood from three swine was used to create four EBC types. The Gralla model of thrombin-induced barium-opaque EBC served as the control.

Retention of an autologous endothelial layer on a bioprosthetic valve for the treatment of chronic deep venous insufficiency.

Purpose: Percutaneous transcatheter implantation of porcine small intestinal submucosa (SIS) bioprosthetic valves has been reported as a treatment for chronic deep venous insufficiency (CDVI). Endothelial progenitor outgrowth cells (EOCs), isolated from whole ovine blood, were evaluated as a source of in vitro autologous seeding for SIS endothelialization. Retention of the EOC monolayer was evaluated to test the feasibility of delivering an endothelialized SIS valve.

Twin valve caval stent for functional replacement of incompetent tricuspid valve: a feasibility animal study.

Objective: To evaluate feasibility of a twin valve caval stent (TVCS) for functional replacement of an incompetent tricuspid valve (TV) in an acute animal study.

Methods: One swine and three sheep were used in the study. TVCS placement was tested in a swine with a normal TV.

Infrahepatic caudal/inferior vena cava interruption with azygos/hemiazygos continuation. Vascular anomaly in swine.

Background: Swine are commonly used as a model to study congenital cardiovascular defects that occur in humans and these models have been both spontaneous and experimentally induced. Ventricular septal defect, patent ductus arteriosus, and atrial septal defect (ASD) are examples of experimentally induced models. Absence of caudal/inferior vena cava (CVC/IVC) with azygos/hemiazygos continuation is an uncommon vascular anomaly.

New coaxial transseptal needle for creation of atrial septal defects in adult sheep.

Objectives: To introduce a new transseptal (TS) needle assembled in our laboratory--the coaxial TS (CTS) needle--and describe our experience with it in creating experimental atrial septal defects (ASD) in adult sheep.

Background: With commercially available TS needles, we were not able to consistently perform TS puncture at the fossa ovalis in adult sheep.

Material And Methods: Ten adult sheep with a mean weight of 63.

Hemostatic efficacy of chitosan-based bandage for closure of percutaneous arterial access sites: An experimental study in heparinized sheep model.

Background: Most of the presently used percutaneous arterial closure devices (PACD) for hemostasis after interventional vascular procedures are effective, but carry risk of complications by deposition of a foreign body. A new promising externally applied PACD - chitosan-based HemCon Bandage (HCB) was explored in sheep. The HCB hemostatic efficacy and complications occurring with its use were compared to those with the standard manual compression (SMC).

Biodisk: a new device for closure of patent foramen ovale: a feasibility study in swine.

Purpose: To evaluate the feasibility, effectiveness, and safety of a porcine small intestinal submucosa (SIS)-covered Biodisk (BD) for the closure of patent foramen ovale (PFO) in swine.

Methods: Twelve piglets (9-30 kg) with PFO ranging in size from 6 to 12 mm were used for the in vivo testing. The BD device consisted of two basic nitinol wire components covered with platinum coil, a flexible SIS-covered ring, and an anchor.

Small intestinal submucosa plug for closure of dilated nephrostomy tracts: a pilot study in swine.

The aim of this study was to evaluate efficacy of a plug made of small intestinal submucosa (SIS) for closure of dilated nephrostomy tract in the kidney after nephroscopy. Ten kidneys in 5 swine had nephrostomy tracts dilated up to 8 mm. The SIS plug was placed into the dilated renal cortex under nephroscopic control.

A new cone-shaped aortic valve prosthesis for orthotopic position: an experimental study in Swine.

The aim of this experimental study was to evaluate a newly designed cone-shaped aortic valve prosthesis (CAVP) for one-step transcatheter placement in an orthotopic position. The study was conducted in 15 swine using either the transcarotid (11 animals) or the transfemoral (4 animals) artery approach. A 12- or 13-Fr sheath was inserted via arterial cutdown.

Thrombus formation after percutaneous catheterization and manual compression of the femoral artery in heparinized sheep.

The purpose of this study was to evaluate the angiographic and histopathologic changes in the superficial femoral artery (SFA) in heparinized sheep shortly after catheterization with an 8-Fr sheath and manual compression hemostasis either with standard manual compression (SMC) or with the use of a procoagulant chitosan-based HemCon Bandage. The evaluation was done in 38 SFAs of 19 heparinized (100 mg/kg) sheep. After a 5-min catheterization with an 8-Fr sheath, a 5-min compression was applied.

Optional vena cava filter with disengaging centering struts: retrieval in an animal model.

An optional inferior vena cava (IVC) filter prototype was evaluated for safety and long-term retrievability as an initial feasibility study in an animal model. This filter has four centering struts that have the ability to disengage from the filtering cone portion, allowing the legs to slide out of endothelial growth. Retrieval of six filters in three animals was successful up to 27 weeks.

Angiographic evaluation of carotid artery grafting with prefabricated small-diameter, small-intestinal submucosa grafts in sheep.

The purpose of this study was to report the longitudinal angiographic evaluation of prefabricated lyophilized small-intestinal submucosa (SIS) grafts placed in ovine carotid arteries and to demonstrate a variety of complications that developed. A total of 24 grafts, 10 cm long and 6 mm in diameter, were placed surgically as interposition grafts. Graft patency at 1 week was evaluated by Doppler ultrasound, and angiography was used for follow-up at 1 month and at 3 to 4 months.

Testing percutaneous arterial closure devices: an animal model.

The ovine superficial femoral artery was used for testing the efficacy of percutaneous arterial closure devices (PACDs) in their developmental stage. Two topical devices containing chitostan, one staple-mediated PACD and a porcine small intestinal submucosa plug, were tested by follow-up angiography in 37 sheep. Absence or presence of bleeding and time to bleeding cessation were the main criteria for evaluation of PAVD efficacy.

Percutaneous management of chronic deep venous reflux: review of experimental work and early clinical experience with bioprosthetic valve.

Lower extremity chronic deep venous insufficiency (CDVI) is common and remains a major health problem worldwide. Selected patients benefited from direct deep vein valve surgical repair or valve transplantation. A major limitation of this approach is that most of the patients are not candidates for these procedures due to obstructions or residual thrombus throughout the vein.

Animal model for percutaneous creation of traumatic thoracic aortic transection.

Purpose: This study was conducted to create an animal model for thoracic aortic transection that is suitable for thoracic endograft research.

Materials And Methods: Percutaneous aortic transection creation was attempted in 12 sheep. A custom collapsible circumferential cutting device was inserted into the proximal descending thoracic aorta via a femoral approach with an 11-F delivery catheter.

Experimental ovine model of primary venous valve incompetence: a pilot study.

Purpose: To compare two techniques used to create a larger animal model of venous valve incompetence.

Materials And Methods: To achieve vein dilatation as the primary cause of valve incompetence, common carotid jugular vein (JV) fistulas were created and optional filters were placed into the JV of sheep. Altogether, nine inferior vena cava filters were placed in three sheep in two stages.

Percutaneous autologous venous valve transplantation: short-term feasibility study in an ovine model.

Background: Limited experience with bioprosthetic venous valve percutaneously inserted into femoral veins in 15 patients has been promising in short-term results only to show disappointing long-term results. Percutaneous autogenous venous valve (PAVV) transplantation was explored in an ovine model as a possible alternative treatment.

Methods: PAVV consisted of a vein segment containing a valve that was attached to a stent template.

Percutaneous vein occlusion with small intestinal submucosa: an experimental pilot study in Swine and sheep.

Purpose: The objective of this study was to investigate the feasibility, outcomes, and amount of small intestinal submucosa (SIS) material needed for embolization of jugular vein (JV) in a swine and sheep model. Our hypothesis was that SIS would cause vein occlusion.

Materials And Methods: The external JVs (EJV) in swine (n = 6) and JVs in sheep (n = 6) were occluded with SIS fan-folded compressed strips.

Angioscopy for experimental evaluation of optional IVC filters.

Purpose: To demonstrate the feasibility of direct angioscopic visualization of an optional inferior vena cava (IVC) filter in situ and during retrieval.

Materials And Methods: Angioscopy was used for direct visualization of optional IVC filters in six sheep. Cavograms were obtained before the filters were retrieved.

Percutaneous technique for creation of tricuspid regurgitation in an ovine model.

Experimental models of tricuspid regurgitation (TR) are needed to study the percutaneous placement of prosthetic atrioventricular valves. The purpose of this study was to develop an appropriate simple and reproducible percutaneous experimental model for creation of tricuspid regurgitation. Tricuspid regurgitation was successfully created through papillary muscle avulsion using a guide-wire loop in seven sheep with regurgitation documented on right ventricular angiograms and a significant increase in heart rate and right atrial pressures.