Prospective TRACER Trial Evaluates Harpoon Medical's Mitral Valve Repair System
November 1, 2017—Findings from the TRACER trial evaluating the safety and performance of the Harpoon mitral valve repair system (H-MVRS; Harpoon Medical, Inc.) were presented at TCT 2017, the 29th annual Transcatheter Cardiovascular Therapeutics scientific symposium being held October 30 to November 2 in Denver, Colorado. The study was simultaneously published online by James S. Gammie, MD, et al in Journal of the American College of Cardiology (JACC).
The H-MVRS is a transesophageal echocardiographic-guided device designed to implant artificial expanded polytetrafluoroethylene (ePTFE) cords on mitral leaflets in the beating heart.
As summarized in JACC, this prospective multicenter study included 30 consecutive patients with severe degenerative mitral regurgitation (MR) who were treated with H-MVRS via small left thoracotomy. The primary 30-day endpoint was successful implantation of ePTFE cords with a reduction in MR to moderate or less; this was met in 90% (27/30) of patients. Three patients required conversion to open mitral surgery. There were no deaths, strokes, or permanent pacemaker implantations. At 1 month, MR was mild or less in 89% (24/27) and moderate in 11% (3/27).
At 6 months, MR was mild or less in 85% (22/26), moderate in 8% (2/26), and severe in 8% (2/26). Favorable cardiac remodeling at 6 months included decreases in end-diastolic (161 ± 36 to 122 ± 30 mL; P < .001) and left atrial volumes (106 ± 36 to 69 ± 24 mL; P < .001). The anteroposterior mitral annular dimension decreased from 34.7 ± 5.8 to 28.2 ± 5.1 mm; P < .001 as did the mitral annular area (10.0 ± 2.7 vs 6.9 ± 2 cm2; P < .0001).
In JACC, the investigators concluded that H-MVRS ePTFE cordal implantation can reduce the invasiveness and morbidity of conventional mitral valve surgery. The safety profile of the device is promising, but prospective trials comparing the outcomes of H-MVRS to conventional mitral valve repair surgery are warranted.