Does Different Orientation of the Medtronic Hall Tilting Disc Valve in the Aortic Position Effect Transvalvuler Pressure Gradients?

Abstract

The effect of valve orientation during aortic valve replacement (AVR) with the Medtronic Hall (MH) tilting disc valve on transvalvuler pressure gradients was evaluated. 30 patients (pts) undergoing isolated AVR received a MH which was oriented so that the greater opening of the valve faced the non coronary aortic sinus. There were 12 male and 8 female pts in this group with a mean age of 59 +/- 5.2 years. An echocardiographic examination was performed 6 days after the operation and resting transvalvuler gradients were measured (Group 1). The gradients were compared with the results of 30 pts. who had undergone AVR with the same valve previously but with the orientation of the greater opening towards the left or the right coronary sinus (Group 2). In Group 1 the mean valve size was 22 mm. and the measured mean valvuler gradient was 24/13 mmHg (peak/mean). In Group 2 the mean valve size was 22.1 mm. and the measured mean valvuler gradient was 31/20 mmHg (peak/mean). Student's t test was used for statistical analysis and transvalvular gradients in Group 1 were found to be significantly lower than Group 2 (p>005). Implantation with greater opening of the tilting mechanical valve facing the non-coronary sinus seems to result in lower transvalvuler gradients than other orientations.