Effect of variable annular reduction on functional tricuspid regurgitation and right ventricular dynamics in an ovine model of tachycardia-induced cardiomyopathy.

Objective: To investigate the effect of variable tricuspid annular reduction (TAR) on functional tricuspid regurgitation (FTR) and right ventricular (RV) dynamics in ovine tachycardia-induced cardiomyopathy.

Methods: Nine adult sheep underwent implantation of a pacemaker with an epicardial lead and were paced at 200 to 240 bpm until the development of biventricular dysfunction and functional TR was noted. During reoperation on cardiopulmonary bypass, 6 sonomicrometry crystals were placed around the tricuspid annulus (TA) and 14 were placed on the RV epicardium.

The influence of tricuspid annuloplasty prostheses on ovine annular geometry and kinematics.

Background: Surgical repair of functional tricuspid regurgitation is centered on annular reduction with artificial rings; however, the precise effect of prosthesis implantation on annular geometry, dynamics, and strain is unknown.

Methods: Forty healthy sheep had sonomicrometry crystals implanted around the tricuspid annulus and onto right ventricle free wall. Ten animals underwent tricuspid annuloplasty with a flexible Duran AnCore ring (Medtronic, Minneapolis, Minn) (28 ± 1 mm), 10 with Contour 3D rigid ring (Medtronic) (29 ± 1 mm), 10 with hybrid Tri-Ad Adams band (Medtronic) (28 ± 1 mm), and 10 had no prosthesis (control group).

Impact of tricuspid annular size reduction on right ventricular function, geometry and strain.

Objectives: Restrictive tricuspid annuloplasty is a clinically accepted approach to treat functional tricuspid regurgitation. We set out to investigate the effect of varying degrees of tricuspid annular reduction on the right ventricular (RV) function, geometry and strain.

Methods: Eight, healthy sheep (45 ± 4 kg) had 6 sonomicrometry crystals implanted around the tricuspid annulus and 20 onto the epicardium of the right ventricle defining 3 free wall regions: basal, mid and lower.

Right ventricular free wall stress after tricuspid valve annuloplasty in acute ovine right heart failure.

Background: Tricuspid annuloplasty rings may have a direct impact on right ventricular shape and free wall stress, potentially affecting chamber remodeling and recurrent regurgitation. In an acute model of ovine right heart failure, we investigated right ventricular free wall stress after annuloplasty with different prostheses.

Methods: Thirty-xix sheep underwent implantation of sonomicrometry crystals on the tricuspid annulus and right ventricle.

Sonomicrometry-derived 3-dimensional geometry of the human tricuspid annulus.

Objectives: Surgical correction of functional tricuspid regurgitation is focused on prosthetic reduction and remodeling of the tricuspid annulus. We set out to investigate the precise geometry of the human tricuspid annulus to better guide surgical therapy.

Methods: Eleven human donor hearts with normal right ventricular function and without tricuspid regurgitation that were rejected for clinical transplantation were harvested.