Thrombolysis for Lower-Extremity Deep Vein Thrombosis

A Retrospective Comparison of Catheter-Directed Thrombolysis versus Pharmacomechanical Thrombolysis for Treatment of Acute Lower Extremity Deep Venous Thrombosis

BACKGROUND

Pharmacomechanical thrombolysis (PMT) and catheter-directed thrombolysis (CDT) are frequently employed for treating deep venous thrombosis (DVT). However, there have been relatively few studies comparing PMT outcomes to those associated with CDT. The present study was thus designed to compare short- and mid-term PMT and CDT patient outcomes following the treatment of DVT of the lower extremities.

METHODS

This study was a retrospective analysis of 98 patients treated at the 3rd Affiliated Hospital of Shenzhen University (Shenzhen, China) and Beijing Chao Yang Hospital (Beijing, China). All patients had undergone treatment for symptomatic DVT of the lower legs via either CDT or PMT. Clinical records and outcome data between the patients in these 2 treatment groups were compared.

RESULTS

Of the 98 patients analyzed in this retrospective study, 50 had been treated via CDT while 48 had undergone PMT. These PMT and CDT operations were associated with mean treatment durations of 0.97 ± 0.20 hr and 32.48 ± 7.46 hr, respectively (P < 0.0001). Complete lysis was achieved in 78 patients (42 and 36 in the PMT and CDT groups, respectively P = 0.057), while effective lysis was achieved in 96 patients (48 and 48 in the PMT and CDT groups, respectively P = 0.162), with lysis being ineffective in the 2 remaining patients. PMT was associated with a significantly decreased length of hospital stay, usage of UK dose, and treatment duration relative to CDT(P < 0.0001). No major complications or MACE incidence were noted in either group, although 18 patients in the PMT group suffered from bradyarrhythmia (P = 0.007). Clinical efficacy was achieved in 96 patients (48 in each treatment group) at time of discharge (P = 0.162). A Kaplan-Meier analysis revealed that 2-year primary patency rates did not differ significantly between these 2 groups (P = 0.442).

CONCLUSION

PMT is an effective treatment modality in patients with symptomatic DVT. Relative to CDT it is associated with high treatment success rates, reduced treatment duration, and reduced hospitalization duration, although it is also associated with higher rates of systemic complications.

Overexpressed microRNA-103a-3p inhibits acute lower-extremity deep venous thrombosis via inhibition of CXCL12

Studies have shown that microRNAs (miRNAs) participate in almost all pathological and physiological processes including acute lower-extremity deep venous thrombosis (LEDVT). Here, this study was designed to elucidate the possible function of miR-103a-3p in acute LEDVT. Expression of miR-103a-3p and chemokine C-X-C motif ligand 12 (CXCL12) was initially quantified in plasma collected from 81 LEDVT patients. Then LEDVT mouse models were established by injection with 3% sodium pentobarbital. The interaction between miR-103a-3p and CXCL12 was identified by dual-luciferase reporter gene assay. After gain- and loss-of-function studies, interleukin-6 (IL-6) and IL-8 and tissue factor (TF) levels, and expression of plasminogen activator inhibitors (PAIs), von Willebrand factor (vWF), thromboxane A2 (TH-A2), F4/80, IL-12, Arginase-1 (Arg-1) and CD206 were determined using enzyme-linked immunosorbent assay (ELISA), reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis, respectively. miR-103a-3p was downregulated, while CXCL12 was upregulated in patients and mice with LEDVT. miR-103a-3p targets CXCL12 and inhibited its expression. Overexpressed miR-103a-3p or downregulated CXCL12 decreased expression of IL-6, IL-8, TF, PAIs, vWF, TH-A2, M1 markers (IL-6 and IL-12), yet increased expression of M2 markers (Arg-1 and CD206) in LEDVT mice. Additionally, upregulated miR-103a-3p or silencing CXCL12 suppressed thrombosis in LEDVT mice. However, overexpression of CXCL12 reversed the tendency mentioned above. Altogether, miR-103a-3p can potentially downregulate CXCL12 expression to disrupt inflammatory response and thrombosis, ultimately preventing the development of LEDVT. Our findings underscore a possible alternative therapeutic strategy to limit LEDVT.

Increasing role of interventional cardiologists for peripheral vascular disease

Improvements in the design of endovascular devices and technical skills of interventionalists have opened new possibilities for patients with a wide range of peripheral vascular diseases. In lower extremity peripheral artery disease, percutaneous treatments have become the predominant revascularization strategy for simple and complex lesions. Newer generations of stents and drug-coated balloons have demonstrated strong potential in the treatment of femoropopliteal and infrainguinal diseases. One of the most dramatic advances in the recent past has been endovascular repair of thoracic and abdominal aortic aneurysms, which has become the preferred approach in lieu of open surgical repair. Contemporary trials have established the safety and effectiveness of carotid stenting in selected patients with severe stenosis. Endovascular treatments for venous occlusive disease have long been underutilized, but their effectiveness is being increasingly recognized. This review covers new endovascular procedures performed by interventional cardiologists for peripheral vascular diseases.

Basic data related to thrombolytic therapy for acute venous thrombosis

BACKGROUND

Treatment guidelines for thrombolysis in iliofemoral deep venous thrombosis (DVT) are based on a limited number of observational and prospective studies. The acute venous thrombosis: thrombus removal with adjunctive catheter-directed thrombolysis (ATTRACT) trial will be the first large, multicenter randomized control trial to evaluate the relative advantages of several current treatment strategies. The objective of this study was to summarize the existing data that inform the use of catheter-directed thrombolysis (CDT) or pharmacomechanical thrombectomy in the management of acute iliofemoral DVT.

METHODS

A search of the current literature was done using PubMed, Ovid, and Cochrane databases for all available articles published up to December 2013.

RESULTS

Of those studies, which included at least 25 patients, 19 case series were identified from 1996 to 2012. Treatment groups included anticoagulation, surgical thrombectomy, pharmacomechanical thrombectomy, and CDT. Cases observed in each ranged from 26 to 101. Three studies were identified which derived data from national multicenter registries. Only 2 randomized control trials were identified from 2002 to 2012. Both support the use of CDT over anticoagulation alone for treatment of iliofemoral DVT.

CONCLUSIONS

Present treatment guidelines for acute iliofemoral DVT have been in flux and are derived from a relatively small amount of clinical data. They are summarized here in anticipation of results from the ongoing ATTRACT trial.