Assessment of left ventricular function with 16- and 64-slice multi-detector computed tomography.

Area of Science:

• Cardiovascular Imaging
• Medical Diagnostics
• Radiology

Background:

• Accurate assessment of left ventricular ejection fraction (LVEF) is crucial for cardiac patient risk stratification and management.
• Imaging modalities providing both anatomical and functional data are highly desirable.
• Electrocardiographic (ECG) gated multi-detector computed tomographic (MDCT) imaging can assess LV function, but past systemic errors were linked to slow gantry rotation speeds.

Purpose of the Study:

• To evaluate the accuracy of ECG-gated MDCT in assessing LVEF and LV dimensions.
• To compare the performance of 16-slice and 64-slice MDCT scanners against echocardiography (ECHO) and Tc-99m gated single-photon-emission computed tomography (SPECT).

Main Methods:

• 306 patients underwent ECG-gated cardiac CT studies; 69 with available CT data and recent ECHO/SPECT were included.
• ECG-gated data sets were acquired using either 16-slice or 64-slice MDCT.
• Functional MDCT data were reconstructed in 10 cardiac phases and interpreted by blinded observers.

Main Results:

• The 64-slice MDCT showed very good correlation with combined ECHO/SPECT (r=0.86), ECHO (r=0.89), and SPECT (r=0.90) for LVEF.
• The 16-slice MDCT demonstrated fair correlation with combined ECHO/SPECT (r=0.56), poor with ECHO (r=0.26), and good with SPECT (r=0.76).
• LVEF values from 64-slice MDCT were similar to those from ECHO and SPECT.

Conclusions:

• 64-slice MDCT provides accurate LVEF and LV dimension assessments comparable to echocardiography and Tc-99m gated SPECT.
• The 64-slice MDCT (330 ms gantry rotation) demonstrates superior accuracy compared to 16-slice MDCT (420 ms gantry rotation) for cardiac function evaluation.
• ECG-gated 64-slice MDCT is a valuable tool for assessing cardiac function in patients.