Medtronic has received US Food and Drug Administration (FDA) approval for the DiamondTemp ablation (DTA) system which treats patients with recurrent, symptomatic paroxysmal atrial fibrillation (AF) and who have been unresponsive to drug therapy. The DiamondTemp system is the first FDA-approved, temperature-controlled, irrigated radiofrequency (RF) ablation system with diamonds currently available to deliver ablations.
AF ablation using radiofrequency energy is a minimally invasive approach that aims to create lesions (scar tissue), using heat, to interrupt irregular electrical signals in the heart, a procedure known as pulmonary vein isolation (PVI). Since the pulmonary veins are often a major source of the arrhythmia, PVI via catheter ablation remains the cornerstone treatment for AF patients who are unresponsive to drug therapy.
The DTA system is a temperature-controlled open-irrigated RF ablation system designed to deliver RF energy (heat) during ablations. The DTA system delivers real-time feedback on physical parameters, which can guide physicians as the lesion is being produced.
The DTA catheter is embedded with industrial-grade diamonds, which have 200‒400 times greater thermal conductivity when compared to materials used in conventional RF ablation catheters. This thermal conductivity enables a low irrigation flow-rate, and accurate real-time measurements of tissue temperature, resulting in more efficient energy delivery. As the only open-irrigated RF catheter with industrial diamonds to optimise power based on tissue temperature, the DTA system is safe and effective and has demonstrated procedural efficiencies when compared to conventional contact force-sensing RF catheters.
“With the FDA approval of the DiamondTemp system, Medtronic continues to drive clinical research and innovation to find differentiated solutions that meet the needs of patients and clinicians, who are on the front lines of patient care,” said Rebecca Seidel, president of Cardiac Ablation Solutions, which is reported as part of the Cardiac and Vascular Group at Medtronic. “DTA is the only FDA-approved, temperature-controlled, irrigated RF ablation system on the market today. The addition of DTA will enable Medtronic to continue to expand our portfolio in new ways with cutting edge arrythmia solutions to help patients control their AF.”
The DIAMOND-AF trial is a prospective, multicentre, single blind, non-inferiority, randomised, controlled trial designed to compare the safety and effectiveness of the DTA system against a contact force-sensing ablation system (control arm) for the treatment of patients with recurrent, symptomatic, paroxysmal atrial fibrillation (PAF) whose condition is unresponsive to drug therapy. The trial enrolled 482 patients (239 DTA, 243 control) across 23 sites in the USA, Europe and Canada. DIAMOND-AF is the largest completed AF ablation technology IDE trial which resulted in FDA approval to date.
Results demonstrated a freedom from patient complication rate of 96.7% in the DTA group versus 93.4% in the control (P<0.0001 versus -6.5% non-inferiority margin). Primary effectiveness for the treatment of AF was met in 79.1% of DTA and 75.7% of control subjects (P<0.0001 versus -12.5% non-inferiority margin).
“The DIAMOND-AF trial results are encouraging not only because the DTA system was shown to be safe and effective, but because the outcomes underscored significant procedural efficiencies for clinicians,” said JACC EP corresponding author Tom McElderry, University of Alabama, Birmingham, USA. “Improved efficiencies – including shorter total RF ablation times and individual RF ablation durations, are important for both the well-being of the patient and the productivity of the physician and lab staff.”