Relation between three-dimensional echocardiography derived left ventricular volume and MRI derived circumferential strain in patients eligible for cardiac resynchronization therapy.
OBJECTIVE
To compare regional left ventricular (LV) volume curves obtained with real time three-dimensional echocardiography (RT3DE) with two-dimensional circumferential strain curves obtained by MRI in cardiac resynchronization therapy candidates.


BACKGROUND
Several methods using either ultrasound or MRI are used to quantify mechanical dyssynchrony (MD). Theoretically, LV volume and circumferential strain seem related, since both measures are connected to the radius of the ventricle.


METHODS
In 21 patients with chronic heart failure, RT3DE and tagged MRI were performed subsequently. Regional LV volume was computed from the ultrasound images. From the MR images, regional circumferential strain was calculated. Cross-correlations with time lags of 1% of the cardiac cycle were performed to compare the curves in corresponding LV segments. Furthermore, peak septal to lateral (SL) delays were compared between modalities.


RESULTS
High correlations were found between the curves (r(2) = 0.65 +/- 0.19), but regional differences in time delay between modalities were observed. In the septum, the volume curve was earlier than the strain curve by 1.8 +/- 17.0 time-lags (n.s.), while in the lateral wall, the volume curve was earlier by 3.3 +/- 12.0 time-lags (P < 0.02). There was a non-significant difference between SL delays in the two modalities (volume: -1.0 +/- 8.6%, strain: 3.0 +/- 12.7%, P = 0.17, a positive sign indicates that the lateral wall is delayed).


CONCLUSIONS
High correlations were observed between both modalities, but regional differences in time-delay were found. This is possibly inherent to the method of echocardiographic volume calculation and hampers the comparison of both measures for the quantification of MD.
Rüssel
Iris K
IK
Department of Physics and Medical Technology, VU University Medical Center, De Boelelaan 1118, 1081 HV, Amsterdam, The Netherlands. i.russel@vumc.nl
van Dijk
Jeroen
J
Kleijn
Sebastiaan A
SA
Germans
Tjeerd
T
de Roest
Gerjan
G
Marcus
J Tim
JT
Kamp
Otto
O
Götte
Marco J W
MJ
van Rossum
Albert C
AC
D000328:Adult; D000368:Aged; D002304:Cardiac Pacing, Artificial; D016022:Case-Control Studies; D003287:Contrast Media; D019560:Echocardiography, Three-Dimensional; D005260:Female; D019786:Gadolinium DTPA; D006333:Heart Failure / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery
D003287:Contrast Media; D019786:Gadolinium DTPA