Author + information
- Received July 19, 2010
- Revision received December 6, 2010
- Accepted December 9, 2010
- Published online April 1, 2011.
- Yoshihiro Seo, MD⁎,⁎ (, )
- Tomoko Ishizu, MD⁎,
- Yoshiharu Enomoto, MD†,
- Haruhiko Sugimori, MD† and
- Kazutaka Aonuma, MD⁎
- ↵⁎Reprint requests and correspondence:
Dr. Yoshihiro Seo, Cardiovascular Division, Institute of Clinical Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Japan
Objectives The aim of this experimental study was to validate area tracking by 3-dimensional (3D) speckle tracking imaging (STI) as a method to measure changes in regional left ventricular (LV) endocardial surface area with sonomicrometry and to assess the usefulness as a wall motion evaluation method compared with 1-dimensional strain parameters.
Background A 3D-STI allows for tracking a regional endocardial surface area during a cardiac cycle. Area tracking is a new concept that regional wall motion is quantified through the magnitude of deformation in an endocardial surface area.
Methods In each of 8 anesthetized sheep, sonomicrometry crystals were implanted on the endocardium at the LV mid and apical anterior walls. Area change ratio (ACR) that was a novel parameter obtained by area tracking was measured as percentage change in a segmental area during systole. Segmental longitudinal (LS) and circumferential strain (CS) also were measured by 3D-STI. The ACR, LS, and CS were compared with those by sonomicrometry at baseline and during pharmacological stress tests (dobutamine and propranolol infusion) and acute myocardial ischemia induced by occlusion of mid-left ascending artery.
Results The strong correlation was observed between ACR measurements by 3D-STI and those by sonomicrometry (Y = −4.20 + 0.84X, r = 0.87, p < 0.001). The ACR showed significant relations with both LS and CS (LS: Y = −15.1 + 1.73X, r = 0.73, p < 0.001; CS: Y = −5.85 + 1.06X, r = 0.79, p < 0.001). ACR showed significant differences among baseline, pharmacological stress, and acute myocardial ischemia. In contrast, LS and CS were reduced significantly during acute ischemia studies compared with those during the other studies; no differences were observed among baseline, propranolol infusion, and dobutamine infusion studies.
Conclusions Area tracking by 3D-STI can estimate changes in LV regional area and might be promising for regional wall motion evaluations.
Dr. Seo was supported by a research grant from Toshiba Medical Systems Corporation. All other authors have reported that they have no relationships to disclose.
- Received July 19, 2010.
- Revision received December 6, 2010.
- Accepted December 9, 2010.
- American College of Cardiology Foundation