Beating-heart mitral valve suture annuloplasty under real-time three-dimensional echocardiography guidance: an ex vivo study.

We are developing an alternative mitral valve suture annuloplasty technique on the beating-heart under real-time three-dimensional echocardiography (RT3DE) guidance. The purpose of this initial study was to evaluate a feasibility of this technique using commercially available suturing devices (Sutur Tek Endo 360-degree, Sutur Tek Inc, North Chelmsford, MA, USA). Isolated porcine hearts (n=10) were mounted in a water-filled tank and attached to an ex vivo pulse simulation device, where varying left ventricle pressures with associated valve motion were generated by pulsatile flow through an apical cannula. The suturing device was inserted through the left atrium. Intra-annular (De Vega type) suture annuloplasty was performed under RT3DE guidance. The procedure was successfully performed in all cases. The diameter of the annulus was effectively reduced (85.5+/-4.2% of original antero-posterior dimension, 86.7+/-6.1% of original transverse dimension). The number of tissue bites was 7.4+/-0.8. The maximum distance between the annulus and sutures placed was 1.1 mm. The total procedure time was 9.4+/-2.4 min. There was no collateral tissue injury in any of the cases. This ex vivo study demonstrates the feasibility of beating-heart mitral valve suture annuloplasty under RT3DE guidance.