Mitral Cerclage Annuloplasty, A Novel Transcatheter Treatment for Secondary Mitral Valve Regurgitation: Initial Results in Swine

OBJECTIVES: We developed and tested a novel transcatheter circumferential annuloplasty technique to reduce mitral regurgitation in porcine ischemic cardiomyopathy. Catheter-based annuloplasty for secondary mitral regurgitation exploits the proximity of the coronary sinus to the mitral annulus, but is limited by anatomic variants and coronary artery entrapment.

METHODS: The procedure, “cerclage annuloplasty,” is guided by magnetic resonance imaging (MRI) roadmaps fused with live X-ray. A coronary sinus guidewire traverses a short segment of the basal septal myocardium to re-enter the right heart where it is exchanged for a suture. Tension is applied interactively during imaging and secured with a locking device.

RESULTS: We found 2 feasible suture pathways from the great cardiac vein across the interventricular septum to create cerclage. Right ventricular septal re-entry required shorter fluoroscopy times than right atrial re-entry, which entailed a longer intramyocardial traversal but did not cross the tricuspid valve. Graded tension progressively reduced septal-lateral annular diameter, but not end-systolic elastance or regional myocardial function. A simple arch-like device protected entrapped coronary arteries from compression even during supratherapeutic tension. Cerclage reduced mitral regurgitation fraction (from 22.8 +/- 12.7% to 7.2 +/- 4.4%, p = 0.04) by slice tracking velocity-encoded MRI. Flexible cerclage reduced annular size but preserved annular motion. Cerclage also displaced the posterior annulus toward the papillary muscles. Cerclage introduced reciprocal constraint to the left ventricular outflow tract and mitral annulus that enhanced leaflet coaptation. A sample of human coronary venograms and computed tomography angiograms suggested that most have suitable venous anatomy for cerclage.

CONCLUSIONS: Transcatheter mitral cerclage annuloplasty acutely reduces mitral regurgitation in porcine ischemic cardiomyopathy. Entrapped coronary arteries can be protected. MRI provided insight into the mechanism of cerclage action. Sam Hubbard Authentic Jersey

PMID: 19660696

Posted in Invasive Imaging, Magnetic Resonance Imaging and tagged , , , , .

3 Comments

  1. Imaging in the context of transcatheter valve procedures is gaining importance. This paper described results of a complex interventional MRI based approach in an animal model.

    See also:

    Shelley Wood
    HeartWire; March 14, 2010

  2. See also:
    Real-time three-dimensional transoesophageal echocardiography for guidance of non-coronary interventions in the catheter laboratory.
    Balzer J, Kelm M, Kühl HP.
    Eur J Echocardiogr. 2009 May;10(3):341-9.
    PMID:

  3. Very interesting approach to mitral annuloplasty! The coronary protection device is quite novel. This type of procedures may become part of the interventionist approach, likely as a combination with other percutaneous methods such as mitral clipping.
    The importance of imaging for pre-procedural planning remains of utmost importance.

Leave a Reply

Your email address will not be published. Required fields are marked *