Patch Angioplasty in the Rat Aorta or Inferior Vena Cava
Summary
We have established a model of pericardial patch angioplasty that can be used in either small-diameter veins or arteries. This model can be used to compare venous and arterial neointimal hyperplasia formation.
Abstract
Pericardial patches are commonly used in vascular surgery to close vessels. To facilitate studies of the neointimal hyperplasia that forms on the patch, we developed a rat model of patch angioplasty that can be used in either a vein or an artery, creating a patch venoplasty or a patch arterioplasty, respectively. Technical aspects of this model are discussed. The infra-renal IVC or aorta are dissected and then clamped proximally and distally. A 3 mm venotomy or arteriotomy is performed in the infrarenal inferior vena cava or aorta of 6 to 8 week-old Wistar rats. A bovine pericardial patch (3 mm x 1.5 mm x 0.6 mm) is then used to close the site using a 10-0 nylon suture. Compared to arterial patches, venous patches show increased neointimal thickness on postoperative day 7. This novel model of pericardial patch angioplasty can be used to examine neointimal hyperplasia on vascular biomaterials, as well as to compare the differences between the arterial and venous environments.
Introduction
Vascular surgeons commonly close blood vessels with pericardial patches, either bovine or porcine, to reduce the risk of restenosis1,2. In arterial surgery, pericardial patch angioplasty reduces the rate of restenosis compared to a primary closure3,4. Patch venoplasty is also similarly performed to close veins, although less frequently when compared to arterial procedures5,6. Patches typically develop neointimal hyperplasia on their luminal surfaces; however, the mechanism of neointimal formation remains unclear, especially in the comparison of differences in neointimal formation between the arterial and venous environments. We previously showed that pericardial patches attract progenitor cells in both the arterial and the venous environments and that venous patch angioplasty shows more aggressive neointimal formation as compared to the arterial patches7,8.
In this study, we describe the rat model of pericardial patch angioplasty that is common to closing both veins and arteries and that may be used to study neointimal formation; this method is a small-animal model of an operative technique commonly used in human patients. The rat model has a larger diameter than the mouse model, facilitating technical aspects of the surgery and improving the learning curve for the model.
Protocol
Representative Results
Discussion
We describe a patch angioplasty model in the rat that can be used in either veins or arteries, creating a patch venoplasty or patch arterioplasty, respectively. Using this pericardial patch model, we showed aggressive and stable neointimal hyperplasia in the rat IVC venoplasty compared to the aortic arterioplasty (Figure 2)7,8.
Several technical aspects are notable. In the aortic arterioplasty, it is important that the…
Disclosures
The authors have nothing to disclose.
Acknowledgements
This work was supported in part by the National Institutes of Health Grants R56-HL095498, R01-HL-095498 (to AD), R01-HL128406, the Merit Review Award I01-BX002336 from the United States Department of Veterans Affairs Biomedical Laboratory Research and Development Program (to AD), a Yale Department of Surgery Ohse award (to AD), a Sarnoff Cardiovascular Foundation Fellowship (to JMS), and through the resources and the use of facilities at the Veterans Affairs Connecticut Healthcare System (West Haven, CT). Bovine pericardial patches were generously provided by LeMaitre Vascular Inc. (Burlington, MA).
Materials
| Bovine pericardial patch | LeMaitre Vascular | |
| Vascular clamp | Roboz Surgical Instrument Co. | RS-5424 |
| Clamp applying forceps | Roboz Surgical Instrument Co | RS-5410 |
| 10-0 Prolene suture | Arosurgical Co. | T05A10N10-13 |
References
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