Munemura Suzuki, Presenter: Nothing to Disclose

Norihiko Kotooka MD,PHD, Abstract Co-Author: Nothing to Disclose

Sho Kudo MD, PhD, Abstract Co-Author: Nothing to Disclose

Kohei Sasaguri MD, Abstract Co-Author: Nothing to Disclose

Masashi Sakuma MD,PHD, Abstract Co-Author: Nothing to Disclose

Koichi Node MD,PHD, Abstract Co-Author: Nothing to Disclose

Kouji Uba RT, Abstract Co-Author: Nothing to Disclose

Kiyoshi Dogomori RT, Abstract Co-Author: Nothing to Disclose

To demonstrate the feasibility of 3 chamber view (3ch.) 3 directionally-encoded cine 2D Phase-Contrast (2D-cine-3 dir. PC) MR Velocity Vector Mapping for the assessment of quantitative cardiac diastolic function  

2D-cine-3dir. PC MRI and trans-thoracic echocardiography (TTE) was performed on 8 normal volunteers. Nine patients were also examined for the evaluation of the cardiac function. From 2D-cine-3dir. PC MRI data, 3ch. velocity vector map were calculated using the GTFlow® software tool. Early diastolic (E) and late diastolic (A) flow were identified on the velocity vector map. To investigate the effect of the position of the region of interest (ROI) on diastolic indices, two time-velocity curve were generated. As a fixed ROI method, a small round ROI was placed on the level of mitral tips when peak E velocity was found, and fixed over the diastolic phase. As a traced ROI method, a small round ROI was placed on the mitral tips and traced over the diastolic phase. The E and A peak velocities were analyzed from each curve (named Emr, Af, and At) and compared with TTE. To evaluate the effect of the direction of the flow measured in these three methods, the angle between the flow and the line from the center of mitral annulus to apex were measured on the velocity vector map. The difference between the velocity measured by TTE and these two methods were compared (Spearman’s rank correlation) with corresponding peak flow.  

The peak Emr velocity was 50.5±14.3 cm/sec. The peak Af, and At velocity were 29.5±10.6 cm/sec and 32.7±9.01 cm/sec , respectively. The mean (SD) difference of these group was 3.15 (6.7) cm/sec. Compared with TTE, MRI underestimated both peak E and A velocity. But, good correlations of E/A ratio of -0.67-point with a Bland-Altman interval of [-13.7 (-0.67) 0.17] for the fixed ROI method, and [-0.48 (-0.11) 0.26] for the traced ROI method were obtained, respectively. The angle of the peak E and A flow did not correlate well with the difference between TTE and MRI indices (P≧0.05).

On the 3ch.2D-cine-3 dir. PC MR Velocity Mapping, E/A ratio showed good correlation with TTE, although the peak E and A velocity were systemically underestimated.  

3ch. 2D-cine-3 dir. PC MR Velocity Vector Mapping can demonstrate quantitative and qualitative assessment for cardiac function and is recommended as a part of routine examination.

Suzuki, M, Kotooka, N, Kudo, S, Sasaguri, K, Sakuma, M, Node, K, Uba, K, Dogomori, K, Evaluation of the Left Ventricular Diastolic Function by Three-Chamber View MR Velocity Vector Mapping: A Preliminary Study.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11020043.html