Comparison of prospective versus retrospective electrocardiogram-gating 320-detector computed tomography coronary angiography with sing heartbeat

Abstract

Objective To compare the diagnostic performance of prospective electrocardiogram (ECG)-gating 320-detectorcomputed tomography coronary angiography (CTCA) versus retrospective ECG-gating CTCA. Methods 500consecutive patients suspected coronary artery disease with heart rate of less than 65 bpm were performed coronary computed tomography angiography (CCTA) with prospective (group P)and retrospective (group R) ECG gating in turn. The image quality was divided into four levels. Success rates, effective radiation dose,image quality and diagnosis were evaluated. Results Success rates of examination in group P and R are100%.Mean patient radiation dose was significantly different in group P (3.28±1mSv) and R(14.36 ±2.3 mSv).131 and 142 of 3750 segments (250 patients x 15 segments per patient) were too small(1.5mm)tobe characterized in group P and R. 96. 51% (3619/3750) and 96.12% (3608/3750) characterized segments were not significantly different in group P and R. 95.09% segments received a score of 4 and 1.09% segments received a score of 3 in group P, while 95.23% and 0.74% in group R.The cause of 2 and 3 points in the two groups was motion artifact. Stair-step artifacts and images scored as 1were not found.Compared with CAG,the sensitivity,specificity,false positive andfalse negative value in group P(86. 49% ,98. 70% ,88. 89% ,98.38%) and R(83. 87% ,98.74% ,89. 65%,97.93%) were not significantly different. Conclusion Although the patient radiation exposure was significantly lower, the diagnostic performance of prospective ECG-gating 320-detector CTCA was comparable with that of retrospective ECG-gating 320-detector CTCA on patients with stable heart rates less than 65 bpm. Key words: Tomography,X-Ray computed; Gated blood-pool imaging; Coronary angiography/MT