New miniature cardiac lead restores timing in a heartbeat
Insertion of a pacemaker helps establish the normal timing pattern of the heartbeat. In addition the CRT pacemaker coordinates the timing of the upper heart chambers (atria) and the two ventricles, the lower heart chambers. However, the low responder rate leaves up to 30 % of patients with no significant benefit.
Heart-stopping technology
Three wires (leads) are connected to the pacemaker inserted just below the collarbone. The leads detect the heart rate and emit tiny electrical pulses to resynchronise the heart. One of the critical components determining the success of CRT therapy is the placement of the left ventricle (LV) lead in the coronary veins. LV architecture varies from patient to patient and is characterised by tortuously narrow veins, making the procedure exceedingly difficult for the surgeon. Nicolas Shan, coordinator of AXONE describes the ambitious project objective: “AXONE project is bringing to market cardiac leads up to five times smaller diameter compared to those used currently.” The Axone™ lead is 0.4 mm in diameter and can be placed in very narrow veins. This means the surgeon has more choices for LV pacing sites and enables physicians to reach any target vein. Axone™ also features four widely spaced electrodes with multipolarity. Potentially, this single lead can deliver ‘true’ multisite LV pacing and subsequently better resynchronisation due to the enlarged pacing area.
Europe-wide clinical trials
AXONE has completed the clinical evaluation of the device to demonstrate product safety and performance. This paves the way for obtaining European market approval of the Axone™ system. Next step is preparation for technology launch worldwide. The first-generation lead design showed good navigability and promising performances. Final design of the system has been specified and prevalidated according to clinical feedback and project advisory board meetings, composed of worldwide key opinion leaders and physicians. Following up on the AXONE trials, the first implantation of the Axone™ lead as part of the Astral-4LV study was successfully performed in 2020 by Frédéric Anselme, main investigator and professor at the University Hospital of Rouen, France. Astral-4LV is a single arm, multicentre clinical trial that will enrol 152 patients at 20 centres in Austria, Germany, Spain, France, Italy, Netherlands and Portugal. The complication-free and LV rhythm success rates will be evaluated at 6 months post-implantation and the patients will be followed for 4 years. A secondary endpoint of the Astral-4LV study will assess the success rate of a bizone LV rhythm, multipoint pacing with distant electrodes. The data from the study will be used to support the CE mark for Axone ™.
EU support from start to finish
Shan thinks partnerships with great European companies such as the medical division of Heraeus, University Hospital of Rouen and Maastricht University have been invaluable. “EU support, for sure, is financial but not only that, guidance from the EU has been evident throughout the project from the first day, at proposal level.” Summing up on the future of the technology, Shan says: “The European project has ended, but Axone™ is just at the beginning. Further clinical demonstrations will demonstrate all the potential of the technology.” Low-responder CRT patients can now hope for improved survival and quality of life.
Keywords
AXONE, lead, left ventricle (LV), Axone™, cardiac resynchronisation therapy (CRT), Astral-4LV, rhythm, pacemaker, ventricle
