Chronic mesenteric ischemia outcome analysis and predictors of endovascular failure.

OBJECTIVE: Outcomes of open revascularization (OR) and endovascular revascularization (ER) for chronic mesenteric ischemia (CMI) were analyzed to identify predictors of endovascular failure. METHODS: A retrospective study was performed of all consecutive patients with CMI (161 patients, 215 vessels) treated from 2008 to 2012. Demographics, comorbidities, clinical presentation, etiology, and treatment modalities were compared. Outcomes included technical success, restenosis requiring reintervention, complications, mortality, and hospital length of stay. RESULTS: There were 116 patients who were first treated with ER (72%) and 45 patients with OR (28%). Overall mortality was 6.8% (11/161). Among the ER patients, 27 developed restenosis and required OR (23%). Patients treated with ER were older (73 vs 66 years; P = .014), had similar comorbidities, and had higher rate of short lesions (≤2 cm) on preoperative angiograms (23% vs 47%; P = .004). Primary patency at 3 years was higher in the OR group compared with the ER group (91% vs 74%; P = .018). Long-term survival rates were higher in the ER group (95% vs 78%; P = .003). Hospital length of stay and intensive care unit length of stay were shorter in the ER group (<.001). Perioperative mortality (30-day) was not statistically significant between the groups (5.2% vs 11%; P = .165). A subgroup analysis was performed between the patients with successful ER and failure of ER requiring OR. Patients with failure of ER had significantly higher rates of aortic occlusive disease (86% vs 49%; P = .005) and long lesions ≥2 cm on angiography (57% vs 12%; P < .001) that were close to the mesenteric takeoff. Perioperative mortality was higher in the ER failure group (15% vs 2%; P = .009). CONCLUSIONS: ER has similar perioperative mortality and shorter hospitalization but higher rate of restenosis requiring reintervention compared with OR. Patients with ER who required reintervention appear to have longer lesions as well as higher rates of aortic occlusive disease on preoperative angiography. Patients who crossed over from ER to OR had higher perioperative mortality than either primary open or endovascular patients. These findings may guide treatment selection in patients with CMI undergoing ER or OR.

Age-related Notch-4 quiescence is associated with altered wall remodeling during vein graft adaptation.

BACKGROUND: The link of aging to specific mechanisms of vascular biology is not well understood. We have previously shown that aging is associated with increased vein graft wall thickness and that this process involves the VEGF-Delta/Notch-ephrin/Eph cascade. Therefore, we examined whether Dll-4 or Notch-4 are differentially expressed, according to age, during vein graft adaptation. MATERIALS AND METHODS: Vein grafts were performed in 6-mo and 24-mo Fischer 344 rats. Gene expression was analyzed by quantitative real-time PCR, and the distribution of Dll-4 and Notch-4 was observed by immunofluorescence. RESULTS: The expression of Dll-4 and Notch-4 was reduced in vein grafts performed in aged rats compared with the expression in young adult rats. Both Dll-4 and Notch-4 were distributed in vein graft endothelium as well as the outer adventitia, with reduced amounts in the outer adventitia of aged vein grafts. Aged veins had reduced eNOS membrane targeting and colocalization with caveolin-1 as well as reduced eNOS protein expression in comparison to young adult veins. In an exchange model between young and aged animals, heterogeneous vein grafts (Yo(Ag) and Ag(Yo)) showed significantly thicker neointima compared with young (Yo(Yo)) controls, and had Notch-4-positive cells, but not Dll-4-positive cells, diminished in the adventitia. Vein grafts that were air-denuded of endothelium did not show any adaptation to the arterial environment and also lacked both Dll-4 and Notch-4 expression at 3 wk. CONCLUSIONS: During vein graft adaptation to the arterial environment, both Dll-4 and Notch-4 expression are down-regulated in an aged, but not a young, background. Loss of Notch-4 is associated with loss of attenuation of neointima. The delta-Notch signaling pathway may be active during vein graft adaptation.

Basic data related to surgical infrainguinal revascularization procedures: a twenty year update.

In 1990, Dalman and Taylor published a compilation of reported data that were identified by them as related to infrainguinal revascularization procedures in peripheral vascular surgery during the decade of the 1980s. The intervening 20 years has seen revolutionary advances in the field of peripheral vascular surgery, especially in the adoption of endovascular techniques, and an explosion of data related to emerging technologies in the field of infrainguinal revascularization. The tables in this manuscript reflect the evolution of our surgical knowledge during the turn of the 21st century. The superior patency of autologous saphenous vein in all positions is reaffirmed.

Current usage and future directions for the bovine pericardial patch.

Bovine pericardium (BP) is widely used in surgery and is commonly used as a patch after arteriotomy in cardiovascular surgery. BP patches have several advantages compared with prosthetic patches, including superior biocompatability, easy handling, less suture line bleeding, and possibly reduced rates of infection. These advantages of BP have led to its common use during carotid endarterectomy (CEA). However, long-term clinical results reported after CEA have suggested several issues that may be related to the patch, including restenosis, pseudoaneurysm formation, infection, fibrosis, calcification, and thrombosis. These complications may diminish the long-term efficacy of CEA and suggest potential areas for improvement of surgical patches. Understanding the mechanisms by which BP heals after patch angioplasty may lead to next generation tissue-engineered patches.

Mechanisms of vein graft adaptation to the arterial circulation: insights into the neointimal algorithm and management strategies.

For patients with coronary artery disease or limb ischemia, placement of a vein graft as a conduit for a bypass is an important and generally durable strategy among the options for arterial reconstructive surgery. Vein grafts adapt to the arterial environment, and the limited formation of intimal hyperplasia in the vein graft wall is thought to be an important component of successful vein graft adaptation. However, it is also known that abnormal, or uncontrolled, adaptation may lead to abnormal vessel wall remodeling with excessive neointimal hyperplasia, and ultimately vein graft failure and clinical complications. Therefore, understanding the venous-specific pathophysiological and molecular mechanisms of vein graft adaptation are important for clinical vein graft management. Of particular importance, it is currently unknown whether there exist several specific distinct molecular differences in the venous mechanisms of adaptation that are distinct from arterial post-injury responses; in particular, the participation of the venous determinant Eph-B4 and the vascular protective molecule Nogo-B may be involved in mechanisms of vessel remodeling specific to the vein. This review describes (1) venous biology from embryonic development to the mature quiescent state, (2) sequential pathologies of vein graft neointima formation, and (3) novel candidates for strategies of vein graft management. Scientific inquiry into venous-specific adaptation mechanisms will ultimately provide improvements in vein graft clinical outcomes.

Age-related neointimal hyperplasia is associated with monocyte infiltration after balloon angioplasty.

Carotid angioplasty is associated with adverse events in elderly patients; it is unclear whether this is related to an altered inflammatory axis. The carotid arteries of young (6 months) or aged (22-24 months) Fischer 344 rats were balloon injured. Aged rats had reduced lumen area (0.18 ± 0.03 vs 0.24 ± 0.01 mm(2), p = .02) and increased neointimal thickening (0.15 ± 0.04 vs 0.08 ± 0.03 mm(2), p = .006). Aged rats had increased circulating monocytes (96 ± 21 vs. 54 ± 7; p = .002) as well as increased numbers of monocytes at the post-angioplasty site. Aged rats had sustained monocyte chemotactic protein-1 expression after angioplasty but young rats did not. Aged arteries also exhibited defective vasorelaxation and abnormal eNOS localization. Aged (≥80 years) human patients with high-grade carotid stenosis had increased number of monocytes (9.1% ± 0.4%) compared with younger (65-80 years) patients (8.1% ± 0.3%, p = .013). Aged rats develop neointimal hyperplasia after carotid angioplasty with increased numbers of monocytes, and elderly humans with carotid stenosis have increased numbers of circulating monocytes. These preliminary results may suggest a role for monocytes in the response to carotid angioplasty.