Thorac Cardiovasc Surg 2016; 64 - OP230
DOI: 10.1055/s-0036-1571660

Quantification and Clinical Relevance of the Aortic Annulus Plane Orientation in Transcatheter Aortic Valve Implantation

A. Holzamer 1, D. Camboni 1, K. Debl 2, D. Endemann 2, Y. Zausig 3, M. Hilker 1, C. Schmid 1
  • 1University of Regensburg Medical Center, Cardiothoracic Surgery, Regensburg, Germany
  • 2University of Regensburg Medical Center, Cardiology, Regensburg, Germany
  • 3University of Regensburg Medical Center, Anaesthesiology, Regensburg, Germany

Objectives: In some patients who undergo transcatheter aortic valve implantation (TAVI), the aortic annulus is more vertically or horizontally orientated than in standard cases.

We demonstrate a method to calculate the solid angle between the patient's longitudinal axis and the aortic annulus plane that represents this anatomical aspect. Furthermore, we investigated its impact on residual aortic regurgitation after TAVI.

Methods: For TAVI purposes, the aortic annulus plane is defined by the three lowest points of the valve's cusps (“hinge points”). In 588 patients, we measured the coordinates of the hinge points by 3D CT analysis prior to TAVI.

The solid angle between the annulus plane given by the coordinates and the patient's longitudinal axis was calculated using vector mathematics.

Post-procedural aortic valve regurgitation (AR) was examined by TEE and fluoroscopy in all cases.

For TA versus TF approach and each type of prostheses with at least 50 performed implantations in the cohort, the correlation between AR and the solid angle was examined using Spearman's correlation.

Results: The mean solid angle was 49,5° ( ±  8,7°). Extreme values were 79,7° and 27,9°, respectively. There was no significant correlation between the angle and patient's gender or preoperative LVEF.

In the TF collective (n = 358), significant positive correlation between AR and the solid angle was given (p = .025). The examined TF valves (Corevalve [n = 63], Sapien 3/XT [n = 140/87], Symetis neo [n = 65]) showed positive correlation coefficients, but only in the Corevalve cohort significance of the correlation (p< 0.001) was observed.

The TA cohort (n = 230) showed negative but non-significant correlation. This finding was equal in both relevant subgroups (Symetis TA [n = 151], Medtronic Engager [n = 53]).

Conclusion: The strongly varying angle between the patient's longitudinal axis and the aortic annulus plane should be considered in TAVI planning. It might influence the choice of type of prostheses as well as delivery approach. The presented method allows a standardized and fast quantification of this angle.