Key messages
⦁ The effects of angioplasty or stenting for people with deep vein thrombosis (DVT) are unclear.
⦁ Further larger studies are needed to determine whether angioplasty and stenting are safe and effective treatments for people with DVT.
What is deep vein thrombosis (DVT)?
DVT is a blood clot that forms in a deep vein, usually in the leg. It can cause pain, swelling, and redness in the affected leg. DVT can also lead to serious complications, such as post-thrombotic syndrome (PTS) (a chronic condition that develops after DVT) and pulmonary embolism (PE) (when a part of the DVT clot breaks off and travels to the lungs).
How is DVT treated?
DVT is usually treated with blood thinners to prevent the clot from getting bigger and to stop it from breaking off and travelling to the lungs. Other treatments for DVT include compression stockings and procedures (including angioplasty and stenting). Angioplasty and stenting are used to open blocked blood vessels and keep them open, which can help improve blood flow and reduce symptoms.
What did we want to find out?
We wanted to find out whether angioplasty or stenting is a safe and effective treatment for people with DVT.
What did we do?
We reviewed the evidence for studies looking at whether angioplasty and stenting are safe and effective treatments for people with DVT. We compared and summarised the results of the studies and rated our confidence in the evidence based on factors such as study methods and sizes.
What did we find?
We found two studies that included a total of 134 people with DVT. Both studies were conducted in China and lasted 12 to 36 months. The effects of angioplasty or stenting on PTS, the ability to keep blood vessels open in the long term, quality of life, and unwanted effects are unclear. Effects on new DVT events, PE, deaths, and bleeding are also unclear or were not assessed by the included studies.
What are the limitations of the evidence?
We have little confidence in the evidence. The trials were small and had some serious limitations. For people with a most recent history of (acute) DVT, the fact that the two groups in the study were not the same size and that some people in one group had different vein access may have prevented a fair comparison between study groups. It is difficult to blind people involved in this type of intervention, but the researchers should have reported whether they blinded the people assessing outcomes.
How up-to-date is this evidence?
This evidence is current to April 2023.
Although angioplasty or stenting may increase secondary patency in people with acute obstruction due to DVT, the evidence is very uncertain; the evidence is also very uncertain about the effect of angioplasty or stenting on PTS, quality of life, and adverse events in people with acute obstruction due to DVT. The effects on VTE, mortality, and major bleeding were not estimable or not assessed by the included studies. Future trials must be large enough to detect significant clinical outcomes, and provide data on original stenosis before angioplasty or stenting and differing times from the initial event, among other essential characteristics.
The best medical treatment (BMT) for treating deep venous thrombosis (DVT) includes anticoagulation and compression stockings. Angioplasty and stenting restore vessel patency and facilitate blood flow. In some people with DVT, angioplasty or stenting is used to minimise complications such as post-thrombotic syndrome (PTS), but their effects are under discussion.
To assess the effects of adjunctive angioplasty or stenting on a background treatment of anticoagulation and thrombolysis, compared with BMT, sham procedure, thrombolysis, or any combination of these treatments, in people with DVT.
We searched CENTRAL, MEDLINE, Embase, LILACS, IBECS, CINAHL, and AMED databases, as well as the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers, to 20 April 2023. We checked the bibliographies of included trials for further references to relevant trials and contacted specialists in the field, manufacturers, and authors of the included trials for any unpublished data.
We included randomised controlled trials (RCTs) comparing angioplasty or stenting on a background treatment of anticoagulation and thrombolysis, compared with BMT, sham procedure, thrombolysis, or any combination of these treatments, in the management of people with acute obstruction due to DVT. We excluded participants who had a baseline PTS diagnosis or who had received any form of mechanical thrombectomy, as this was investigated in a separate Cochrane review.
We used standard Cochrane methods. The primary outcomes were PTS and venous thromboembolism (VTE); secondary outcomes were mortality, major bleeding, secondary patency, duration of hospitalisation, quality of life (QoL), and adverse events. We used the Cochrane RoB 1 tool to assess the risk of bias for RCTs and GRADE to assess the certainty of evidence. We performed meta-analysis where appropriate.
We included two RCTs (134 participants) that were conducted in China and presented comparisons for acute obstruction after DVT based on length of follow-up (12 months (early), 24 months (intermediate), and 36 months (long term)).
Angioplasty or stenting plus BMT and thrombolysis versus BMT and thrombolysis for acute obstruction due to DVT (intermediate time point)
In the intermediate time point, angioplasty or stenting may have little to no effect on PTS (Venous Clinical Severity Score (VCSS): mean difference (MD) −3.21, 95% confidence interval (CI) −7.74 to 1.33; 2 studies, 133 participants; very low-certainty evidence) and adverse events (limb pain) (risk ratio (RR) 0.68, 95% CI 0.04 to 10.33; 1 study, 67 participants; very low-certainty evidence), but the evidence is very uncertain. Angioplasty or stenting may increase secondary patency (RR 0.26, 95% CI 0.11 to 0.59; 2 studies, 133 participants; very low-certainty evidence), but the evidence is very uncertain. The evidence is very uncertain about the effect of angioplasty or stenting on quality of life (MD 10.54, 95% CI −1.34 to 22.41; 2 studies, 133 participants; very low-certainty evidence), and is not estimable for VTE, mortality, or major bleeding. We downgraded the certainty of evidence for all reported outcomes in this comparison by two levels due to serious study limitations (risk of performance and other bias), and another level for imprecision (small numbers of events and participants). The imbalance between study group size and different vein access may also have contributed to the high heterogeneity seen in the analyses of these outcomes. We downgraded the certainty of evidence for PTS and quality of life by one level for inconsistency (no similarity of point estimates in any of the included studies, no overlap of CIs, and considerable heterogeneity in results). There is an additional difficulty with blinding personnel in this type of intervention, but the trialists should have reported blinding of outcome assessment.