procedure-for-human-saphenous-veins-ex-vivo-perfusion-external

Procedure for Human Saphenous Veins <em>Ex Vivo</em> Perfusion and External Reinforcement

The mainstay of contemporary therapies for extensive occlusive arterial disease is venous bypass graft. However, its durability is threatened by intimal ...

Brigham and Women's hospital/Harvard Medical School

The saphenous vein is the conduit of choice in bypass graft procedures. Haemodynamic factors play a major role in the development of intimal hyperplasia (IH), and subsequent bypass failure. To evaluate the potential protective effect of external reinforcement on such a failure, we developed an ex vivo model for the perfusion of segments of human saphenous veins under arterial shear stress. In veins submitted to pulsatile high pressure (mean pressure at 100 mmHg) for 3 or 7 days, the use of an external macroporous polyester mesh 1) prevented the dilatation of the vessel, 2) decreased the development of IH, 3) reduced the apoptosis of smooth muscle cells, and the subsequent fibrosis of the media layer, 4) prevented the remodelling of extracellular matrix through the up-regulation of matrix metalloproteinases (MMP-2, MMP-9) and plasminogen activator type I. The data show that, in an experimental ex vivo setting, an external scaffold decreases IH and maintains the integrity of veins exposed to arterial pressure, via increase in shear stress and decrease wall tension, that likely contribute to trigger selective molecular and cellular changes.

The use of external mesh reinforcement to reduce intimal hyperplasia and preserve the structure of human saphenous veins.

Whereas chronic overnutrition is a risk factor for surgical complications, long-term dietary restriction (reduced food intake without malnutrition) protects in preclinical models of surgical stress. Building on the emerging concept that acute preoperative dietary perturbations can affect the body's response to surgical stress, we hypothesized that short-term high-fat diet (HFD) feeding before surgery is detrimental, whereas short-term nutrient/energy restriction before surgery can reverse negative outcomes. We tested this hypothesis in two distinct murine models of vascular surgical injury, ischemia-reperfusion (IR) and intimal hyperplasia (IH).

Alban Longchamp

Department of Surgery

Brigham and Women's hospital/Harvard Medical School

Procedure for Human Saphenous Veins Ex Vivo Perfusion and External Reinforcement

Alban Longchamp

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Department of Surgery

Brigham and Women's hospital/Harvard Medical School

Procedure for Human Saphenous Veins Ex Vivo Perfusion and External Reinforcement

Department of Surgery