Safety and efficacy of endovenous ablation in patients with a history of deep vein thrombosis.

OBJECTIVE: Endovenous ablation is the standard of care for patients with symptomatic superficial venous insufficiency. For patients with a history of deep vein thrombosis (DVT), concern exists for an increased risk of postprocedural complications, particularly venous thromboembolism. The objective of this study was to evaluate the safety and efficacy of endovenous thermal ablation in patients with a history of DVT. METHODS: The national Vascular Quality Initiative Varicose Vein Registry was queried for superficial venous procedures performed from January 2014 to July 2021. Limbs treated with radiofrequency or laser ablation were compared between patients with and without a DVT history. The primary safety end point was incident DVT or endothermal heat-induced thrombosis (EHIT) II-IV in the treated limb at <3 months of follow-up. The secondary safety end points included any proximal thrombus extension (ie, EHIT I-IV), major bleeding, hematoma, pulmonary embolism, and death due to the procedure. The primary efficacy end point was technical failure (ie, recanalization at <1 week of follow-up). Secondary efficacy end points included the risk of recanalization over time and the postprocedural change in quality-of-life measures. Outcomes stratified by preoperative use of anticoagulation (AC) were also compared among those with prior DVT. RESULTS: Among 33,892 endovenous thermal ablations performed on 23,572 individual patients aged 13 to 90 years, 1698 patients (7.2%) had a history of DVT. Patients with prior DVT were older (P < .001), had a higher body mass index (P < .001), were more likely to be male at birth (P < .001) and Black/African American (P < .001), and had greater CEAP classifications (P < .001). A history of DVT conferred a higher risk of new DVT (1.4% vs 0.8%; P = .03), proximal thrombus extension (2.3% vs 1.6%; P = .045), and bleeding (0.2% vs 0.04%; P = .03). EHIT II-IV, pulmonary embolism, and hematoma risk did not differ by DVT history (P = NS). No deaths from treatment occurred in either group. Continuing preoperative AC in patients with prior DVT did not change the risk of any complications after endovenous ablation (P = NS) but did confer an increased hematoma risk among all endovenous thermal ablations and surgeries (P = .001). Technical failure was similar between groups (2.0% vs 1.2%; P = .07), although a history of DVT conferred an increased recanalization risk over time (hazard ratio, 1.90; 95% confidence interval, 1.46, 2.46; P < .001). The groups had comparable improvements in postprocedural venous clinical severity scores and Heaviness, Aching, Swelling, Throbbing, and Itching scores (P = NS). CONCLUSIONS: Endovenous thermal ablation for patients with a history of DVT was effective. However, appropriate patient counseling regarding a heightened DVT risk, albeit still low, is critical. The decision to continue or withhold AC preoperatively should be tailored on a case-by-case basis.

Intravascular lithotripsy for the treatment of inferior mesenteric artery in-stent restenosis.

Endovascular revascularization with intraluminal stenting is the recommended first-line therapy for chronic mesenteric ischemia. However, early recurrence and in-stent thrombosis remain significant challenges. We present the case of a patient with recurrent chronic mesenteric ischemia secondary to in-stent restenosis that was successfully treated with intravascular lithotripsy, a novel, safe approach to stent salvage.

Inhibition of heat shock protein 90 attenuates post­angioplasty intimal hyperplasia.

Intimal hyperplasia (IH) is a pathologic process that leads to restenosis after treatment for peripheral arterial disease. Heat shock protein 90 (HSP90) is a molecular chaperone that regulates protein maturation. Activation of HSP90 results in increased cell migration and proliferation. 17­N­allylamino­17­demethoxygeldanamycin (17­AAG) and 17­dimethylaminoethylamino­17­demethoxygeldanamycin (17­DMAG) are low toxicity Food and Drug Association approved HSP90 inhibitors. The current study hypothesized that HSP90 inhibition was predicted to reduce vascular smooth muscle cell (VSMC) migration and proliferation. In addition, localized HSP90 inhibition may inhibit post­angioplasty IH formation. For proliferation, VSMCs were treated with serum­free media (SFM), 17­DMAG or 17­AAG. The selected proliferative agents were SFM, platelet derived growth factor (PDGF) or fibronectin. After three days, proliferation was measured. For migration, VSMCs were treated with SFM, 17­AAG or 17­DMAG with SFM, PDGF or fibronectin as chemoattractants. Balloon injury to the carotid artery was performed in rats. The groups included in the present study were the control, saline control, 17­DMAG in 20% pluronic gel delivered topically to the adventitia or intraluminal delivery of 17­DMAG. After 14 days, arteries were fixed and sectioned for morphometric analysis. Data was analyzed using ANOVA or a student's t­test. P<0.05 was considered to indicate a statistically significant difference. The results revealed that 17­AAG and 17­DMAG had no effect on cell viability. PDGF and fibronectin also increased VSMC proliferation and migration. Furthermore, both 17­AAG and 17­DMAG decreased cell migration and proliferation in all agonists. Topical adventitial treatment with 17­DMAG after balloon arterial injury reduced IH. HSP90 inhibitors suppressed VSMC proliferation and migration without affecting cell viability. Topical treatment with a HSP90 inhibitor (DMAG) decreased IH formation after arterial injury. It was concluded that 17­DMAG may be utilized as an effective therapy to prevent restenosis after revascularization.

Thrombospondin-5 and fluvastatin promote angiogenesis and are protective against endothelial cell apoptosis.

The thrombospondins (TSPs), multifunctional matricellular proteins, are known mediators of endothelial cell (EC) angiogenesis and apoptosis. TSP-1, an antiangiogenic molecule, is important in the progression of vascular disease, in part by inducing EC apoptosis. TSP-2, although less studied, also induces EC apoptosis and inhibits angiogenesis. The effects of TSP-5 are largely unexplored in ECs, but TSP-5 is believed to be protective against arterial disease. Statin drugs have been shown to have beneficial pleiotropic effects, including decreasing EC apoptosis, increasing angiogenesis, and blocking TSP signaling. We hypothesized TSP-5 will be proangiogenic and antiapoptotic, and statin pretreatment would reverse the proapoptotic and antiangiogenic phenotype of TSP-1 and TSP-2. ECs were exposed to serum-free medium, TSP-1, TSP-2, or TSP-5 with or without fluvastatin pretreatment. Quantitative real-time polymerase chain reaction was performed on 96 apoptosis and 96 angiogenesis-related genes using microfluidic card assays. Angiogenesis was measured using Matrigel assays, while apoptosis was measured by fluorescent caspase assay. TSP-5 suppressed apoptotic genes and had a mixed effect on the angiogenic genes; however, TSP-5 did not alter apoptois but was proangiogenic. Pretreatment with fluvastatin downregulated proapoptotic genes and apoptosis and upregulated proangiogenic genes and angiogenesis. Findings indicate TSP-5 and fluvastatin have a protective effect on ECs, being proangiogenic and reversing the antiangiogenic effects of TSP-1 and TSP-2. In conclusion, TSP-5 and fluvastatin may be beneficial for inducing angiogenesis in the setting of ischemia.