CHIVA method for the treatment of chronic venous insufficiency

Many surgical approaches are available to treat varicose veins secondary to chronic venous insufficiency. One of the least invasive techniques is the ambulatory conservative hemodynamic correction of venous insufficiency method (in French 'cure conservatrice et hémodynamique de l'insuffisance veineuse en ambulatoire' (CHIVA)), an approach based on venous hemodynamics with deliberate preservation of the superficial venous system. This is the second update of the review first published in 2013.To compare the efficacy and safety of the CHIVA method with alternative therapeutic techniques to treat varicose veins.The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, AMED, and the World Health Organisation International Clinical Trials Registry Platform and ClinicalTrials.gov trials registries to 19 October 2020. We also searched PUBMED to 19 October 2020 and checked the references of relevant articles to identify additional studies.We included randomized controlled trials (RCTs) that compared CHIVA to other therapeutic techniques to treat varicose veins.Two review authors independently assessed and selected studies, extracted data, and performed quantitative analysis from the selected papers. A third author solved any disagreements. We assessed the risk of bias in included trials with the Cochrane risk of bias tool. We calculated the risk ratio (RR), mean difference (MD), number of people needed to treat for an additional beneficial outcome (NNTB), and the number of people needed to treat for an additional harmful outcome (NNTH), with 95% confidence intervals (CI). We evaluated the certainty of the evidence using GRADE. The main outcomes of interest were the recurrence of varicose veins and side effects.For this update, we identified two new additional studies. In total, we included six RCTs with 1160 participants (62% women) and collected from them eight comparisons. Three RCTs compared CHIVA with vein stripping. One RCT compared CHIVA with compression dressings in people with venous ulcers. The new studies included three comparisons, one compared CHIVA with vein stripping and radiofrequency ablation (RFA), and one compared CHIVA with vein stripping and endovenous laser therapy. We judged the certainty of the evidence for our outcomes as low to very low due to inconsistency, imprecision caused by the low number of events and risk of bias. The overall risk of bias across studies was high because neither participants nor personnel were blinded to the interventions. Two studies attempted to blind outcome assessors, but the characteristics of the surgery limited concealment. Five studies reported the outcome clinical recurrence of varicose veins with a follow-up of 18 months to 10 years. CHIVA may make little or no difference to the recurrence of varicose veins in the lower limb compared to stripping (RR 0.74, 95% CI 0.46 to 1.20; 5 studies, 966 participants; low-certainty evidence). We are uncertain whether CHIVA reduced recurrence compared to compression dressing (RR 0.23, 95% CI 0.06 to 0.96; 1 study, 47 participants; very low-certainty evidence). CHIVA may make little or no difference to clinical recurrence compared to RFA (RR 2.02, 95% CI 0.74 to 5.53; 1 study, 146 participants; low-certainty evidence) and endovenous laser (RR 0.20, 95% CI 0.01 to 4.06; 1 study, 100 participants; low-certainty evidence). We found no clear difference between CHIVA and stripping for the side effects of limb infection (RR 0.83, 95% CI 0.33 to 2.10; 3 studies, 746 participants; low-certainty evidence), and superficial vein thrombosis (RR 1.05, 95% CI 0.51 to 2.17; 4 studies, 846 participants; low-certainty evidence). CHIVA may reduce slightly nerve injury (RR 0.14, 95% CI 0.02 to 0.98; NNTH 9, 95% CI 5 to 100; 4 studies, 846 participants; low-certainty evidence) and hematoma compared to stripping (RR 0.59, 95% CI 0.37 to 0.97; NNTH 11, 95% CI 5 to 100; 2 studies, 245 participants; low-certainty evidence). For bruising, one study found no differences between groups while another study found reduced rates of bruising in the CHIVA group compared to the stripping group. Compared to RFA, CHIVA may make little or no difference to rates of limb infection, superficial vein thrombosis, nerve injury or hematoma, but may cause more bruising (RR 1.15, 95% CI 1.04 to 1.28; NNTH 8, CI 95% 5 to 25; 1 study, 144 participants; low-certainty evidence). Compared to endovenous laser, CHIVA may make little or no difference to rates of limb infection, superficial vein thrombosis, nerve injury or hematoma. The study comparing CHIVA versus compression did not report side effects.There may be little or no difference in the recurrence of varicose veins when comparing CHIVA to stripping (low-certainty evidence), but CHIVA may slightly reduce nerve injury and hematoma in the lower limb (low-certainty evidence). Very limited evidence means we are uncertain of any differences in recurrence when comparing CHIVA with compression (very low-certainty evidence). CHIVA may make little or no difference to recurrence compared to RFA (low-certainty evidence), but may result in more bruising (low-certainty evidence). CHIVA may make little or no difference to recurrence and side effects compared to endovenous laser therapy (low-certainty evidence). However, we based these conclusions on a small number of trials with a high risk of bias as the effects of surgery could not be concealed, and the results were imprecise due to the low number of events. New RCTs are needed to confirm these results and to compare CHIVA with approaches other than open surgery.