Global cardiac evaluation without heart rate control: Preliminary experience with dual source CT (DSCT)

Aim. The aim of this work was to assess the role of dual source computed tomography (DSCT) in global cardiac evaluation without heart rate control, assessing the effect of average heart rate on coronary image quality, optimal reconstruction interval, ventricular function, and evaluation of left chamber valves. Methods. Fifteen consecutive patients underwent coronary CT angiography. For coronary evaluation, data sets were reconstructed in 5% steps from 30% to 80% of the RR interval. For the assessment of cardiac function, image were reconstructed with a slice thickness of 2.0 mm and 2.0 mm increment, at 10% steps from 0% to 90% of the RR interval. Two blinded independent readers assessed the image quality of the coronary arteries and left chamber valves. Results. The mean heart rate during the scan was 73±11.8 bpm (range 56-97). At the best reconstruction interval excellent diagnostic image quality (score 4) was achieved in 95.5% (43/45) of coronary arteries. Excellent inter-observer agreement was observed for image quality rating (k=0.82). No significant correlation was found between the average heart rate and the mean quality scores (rho=0.29). Comparison of image quality of the coronary arteries in systolic and diastolic reconstructions in each patient showed no statistically significant differences. Conclusion. DSCT is an excellent technique for global cardiac imaging, as it allows to obtain coronary arteries of excellent quality and evaluate ventricular function and valvular area independent of the heart rate.