1110

EP IMAGE

Ventricular Wall Motion Using Three-Dimensional ImagingJASBIR SRA, M.D., DAVID KRUM, M.S., DARIN OKERLUND, M.S.,∗

and KATHERINE PARDO, M.S.∗

From the Electrophysiology Laboratories of St. Luke’s and Aurora Sinai Medical Centers, University of Wisconsin MedicalSchool-Milwaukee Clinical Campus, Milwaukee, Wisconsin, USA; and ∗GE Healthcare, Waukesha, Wisconsin, USA

Patients undergoing cardiac resynchronization therapy(CRT) may benefit from improved methods for determiningthe optimum site for left ventricular (LV) pacing. The newer,high-speed detector computed tomographic scanners are ca-pable of acquiring and processing ventricular wall-motiondata throughout the cardiac cycle. An example during sys-tole and diastole is shown in panel A, with the endocardiumrepresented by the red and epicardium represented by thegreen mesh. This information can be processed to determineoptimal areas for LV pacing, such as the site that is the last to

J Cardiovasc Electrophysiol, Vol. 15, p. 1110, September 2004.

Address for correspondence: Jasbir Sra, M.D., 2801 W. KinnickinnicRiver Parkway #777, Milwaukee, WI 53215. Fax: 414-649-5769; E-mail:bdanek@hrtcare.com

doi: 10.1046/j.1540-8167.2004.04046.x

attain maximum displacement and the last to reach maximumvelocity.

Following scanning and segmentation, each axial slice(thickness 1.25 mm) was divided into 100 chords, represent-ing the full circumference of the axial slice. The wall motionof the endocardium at each of these chords, expressed as adisplacement from end-diastole, was plotted throughout thecardiac cycle. Data from these chords were averaged oversix areas (anterior [A], anterolateral [AL], lateral [L], poste-rior [P], posterolateral [PL], septal [S], anteroseptal [AS]) in5% increments throughout the cardiac cycle. The example inpanel B shows a plot of wall motion versus time for a slicemidway between the apex and the base of the heart. LV wallmotion and velocity also were determined from these data,and a plot of wall motion versus time and velocity versus timefor the same axial slice is shown in panels C and D. By iden-tifying areas of interest, three-dimensional cardiac imagingcreates a roadmap that may help optimize CRT.