The Lama Trial – A Randomized Controlled Trial Comparing Endovenous Laser Ablation Versus Mechanochemical Ablation in the Treatment of Superficial Venous Incompetence

Abstract

Introduction - Endovenous thermal ablation, such as endovenous laser ablation (EVLA), is the recommended first-line treatment for superficial venous incompetence (SVI). However such thermal technique requires tumescent anaesthesia, which can be uncomfortable for the patient. Newer non-thermal techniques such as mechanochemical ablation (MOCA) aim to remove or reduce the need for tumescent and thus reduce pain. This randomized controlled trial compares the two treatments with six months’ follow-up. Methods - Patients undergoing ablation for symptomatic primary unilateral SVI were randomized to EVLA or MOCA. Concomitant phlebectomy was performed on symptomatic visible varicosities. Primary outcome was intra-procedural pain scores on 100mm Visual Analogue Scale. Secondary outcomes included post-procedural pain scores, clinical severity scores, general and disease-specific quality of life measurements, recovery time, and duplex ultrasound assessment. Analysis was performed on an intention to treat basis. Data were analysed using parametric and non-parametric statistical tests as dictated by the distribution of data. Results - 82 patients were randomised (41 MOCA and 41 EVLA). The mean age was 53 and 59% were female. Both groups were well matched at baseline. Patients in the MOCA group experienced significantly less pain during truncal ablation (MOCA median 10 mm (interquartile range 9-24 mm) vs EVLA median 28 mm (interquartile range 19-59 mm), P=0.01). However this benefit was lost following concomitant phlebectomy and there was no significant difference in the overall pain scores by the end of the procedure (P=0.441). Patients in the MOCA group also experienced less pain during the next six post-procedural days (by 5-14 mm, P<0.05). There was no significant difference between the groups for either return to work (MOCA median 7 days (interquartile range 4-14 days) vs EVLA median 6 days (interquartile range 4-14 days), P=0.812) or return to normal activities (MOCA median 2 days (interquartile range 1-3 days) vs EVLA median 3 days (interquartile range 1-7 days), P=0.169). Technical success (MOCA 92% vs EVLA 94%), clinical severity scores, disease-specific quality of life scores were similar between groups at six weeks and six months. There were no significant complications. Conclusion - During truncal ablation, MOCA is less painful than EVLA, but this benefit is lost if concomitant phlebectomy is performed. MOCA appears less painful during the first post-procedural week. Both have similar recovery time, clinical improvement, short-term technical success, quality of life improvement and safety outcomes. Longer follow-up is required.