AIMS: To evaluate the potential for mitral annular (MA) size reduction using a novel device utilising therapeutic ultrasound (TU). METHODS AND RESULTS: The ReCor device (ReCor Medical, Inc., Ronkonkoma, NY, USA, Investigational device, not for use in human application) was studied in a closed chest canine animal model (35 dogs). Under fluoroscopy, a 12 Fr TU balloon catheter was advanced into the left atrium (transseptal approach). The TU balloon was inflated with contrast-saline, positioned at the MA and energy delivered circumferentially, to heat the tissue locally. Five TU applications were delivered (at least 60W for at least 40 sec). Relative to baseline, mitral valve annular diameter reduction (measured by transthoracic echocardiography) was 8.4% immediately post procedure(p<0.001), 8.6% at one week (p<0.001), 8.8% at two weeks (p<0.001), 9.3% at three weeks (p<0.001), 10.8% at four weeks (p<0.001), 8.6% at three months (p<0.001) and 5.7% at six months (p<0.001). Histology showed an increase in elastin associated with tissue thickening at the annular level. Transmission electron microscopy demonstrated a decrease in diameter of individual collagen fibres in treated regions compared to controls. CONCLUSIONS: Therapeutic ultrasound (TU) energy application to the mitral annulus is feasible percutaneously. A reduction in annular dimensions occurs immediately and appears to be durable without peri-annular damage.
AIMS: To evaluate the potential for mitral annular (MA) size reduction using a novel device utilising therapeutic ultrasound (TU). METHODS AND RESULTS: The ReCor device (ReCor Medical, Inc., Ronkonkoma, NY, USA, Investigational device, not for use in human application) was studied in a closed chest canine animal model (35 dogs). Under fluoroscopy, a 12 Fr TU balloon catheter was advanced into the left atrium (transseptal approach). The TU balloon was inflated with contrast-saline, positioned at the MA and energy delivered circumferentially, to heat the tissue locally. Five TU applications were delivered (at least 60W for at least 40 sec). Relative to baseline, mitral valve annular diameter reduction (measured by transthoracic echocardiography) was 8.4% immediately post procedure(p<0.001), 8.6% at one week (p<0.001), 8.8% at two weeks (p<0.001), 9.3% at three weeks (p<0.001), 10.8% at four weeks (p<0.001), 8.6% at three months (p<0.001) and 5.7% at six months (p<0.001). Histology showed an increase in elastin associated with tissue thickening at the annular level. Transmission electron microscopy demonstrated a decrease in diameter of individual collagen fibres in treated regions compared to controls. CONCLUSIONS: Therapeutic ultrasound (TU) energy application to the mitral annulus is feasible percutaneously. A reduction in annular dimensions occurs immediately and appears to be durable without peri-annular damage.
Authors: Maurizio Taramasso; Maximilian Y Emmert; Diana Reser; Andrea Guidotti; Nikola Cesarovic; Marino Campagnol; Alessandro Addis; Fabian Nietlispach; Simon P Hoerstrup; Francesco Maisano Journal: J Cardiovasc Transl Res Date: 2015-05-13 Impact factor: 4.132
Authors: Maurizio Taramasso; Alessandro Candreva; Alberto Pozzoli; Andrea Guidotti; Oliver Gaemperli; Fabian Nietlispach; Jens Barthelmes; Maximilian Y Emmert; Alberto Weber; Stefano Benussi; Ottavio Alfieri; Francesco Maisano Journal: J Thorac Dis Date: 2015-09 Impact factor: 2.895