Five-year results of the LAMA randomised controlled trial (RCT) show that both mechanochemical ablation (MOCA) and modern endovenous laser ablation (EVLA) technology are associated with low procedural and post-procedural pain, while clinical outcomes in the short and medium term are worse for MOCA. This led senior author Daniel Carradice (Hull York Medical School, Hull, UK) to conclude that MOCA “may have a role in a small number of selected patients such as those with a fear of needles”.
First author Arthur Lim (Hull York Medical School, Hull, UK) presented the five-year results at the recent European Venous Forum (EVF 2023; 22–24 June, Berlin, Germany). He began by stating that endovenous thermal ablation (EVTA) is the current first-line treatment for superficial venous incompetence (SVI). Despite this, he noted that it requires tumescent anaesthesia, which has been reported to cause perioperative discomfort.
MOCA offers a non-thermal, non-tumescent alternative to EVTA, and Lim detailed that it combines mechanical and chemical damage to achieve vein occlusion. In addition, he stressed that the longer-term outcomes of MOCA are little known.
The LAMA trial is a single-centre RCT that included adult patients with single-axis unilateral symptomatic SVI who were treated with either MOCA, using the ClariVein device (Merit Medical) with or without phlebectomy, or EVLA—a type of thermal ablation—using the VenaCure laser (AngioDynamics) with or without phlebectomy.
Lim informed EVF attendees that the investigators recruited a total of 150 patients in the LAMA trial, noting that 69 patients in the laser group and 69 in the MOCA group had completed follow-up at one year.
At the one-year follow-up point, Lim recapped that both groups had similar procedural pain scores. However, he added, MOCA had “significantly lower” anatomical occlusion compared to laser. In addition, both groups had similar Venous clinical severity scores (VCSS). “Our results are similar to other RCTs of MOCA,” he said.
After sharing these early results, Lim then underlined the goal for longer-term follow-up in the LAMA trial, which was to determine how reduced anatomical occlusion rates impacted venous health and quality of life.
Lim revealed that 52 patients in the laser group and 57 in the MOCA group completed follow-up out to five years. He reported that, for anatomical occlusion, initial success was achieved in all but two patients in the laser group and all bar one in the MOCA group. Five years after treatment, however, it was observed that EVLA had a “significantly higher” anatomical occlusion rate compared to MOCA.
Regarding total reinterventions, the presenter continued, MOCA had a “significantly higher” number compared to laser—specifically, 16 for MOCA and six for laser.
Lim also communicated clinical outcome scores, first sharing that VCSS scores for both groups were similar at one year and also at five years after treatment. “The improvement in VCSS is maintained from baseline after one year and five years for both groups,” the presenter stated.
For disease-specific quality of life, Lim added that both groups had similar scores at one year and five years after treatment, with the improvement maintained at both one and five years for both groups.
Results were similar for generic quality of life, with both groups showing similar scores at one and five years.
“To conclude, MOCA has significantly lower anatomical occlusion at five years,” Lim said, adding that this treatment option saw a higher reintervention for symptomatic clinical recurrence. The presenter also reiterated that the investigators were unable to detect any difference in clinical outcomes between laser and MOCA at five-year follow-up.
Speaking to Venous News following Lim’s presentation, Carradice summarises that LAMA supports the case that the likely disadvantage of MOCA is reduced anatomical occlusion over time, and that this reduced anatomical occlusion is clinically relevant as it is linked to much higher reintervention. He continues that while there is no significant difference at five years in clinical severity or quality of life between the two treatment methods, this should be interpreted with caution, as it is only after a high rate of reintervention and the smaller numbers in the subgroup analysis are susceptible to type 2 statistical error.
