Introduction and aim:
Dual Source CT (DSCT) scanners, with an increased temporal resolution (83 ms), are becoming widely available. To evaluate the current potential of this scanner in the clinical arena, we performed a head-to-head comparison with conventional coronary angiography (CCA) taking into account the following parameters: radiation exposure, procedure time and contrast load.
Methods:
During a one-year period (april 2006 to march 2007) we compared a consecutive patient group who underwent DSCT (318 patients, 222 male, mean age 68±11 years) and CCA (352 patients, 258 male, mean age 61±12) respectively. Patients with previous bypass surgery were excluded. In DSCT, the volume of iodinated contrast material was adapted to the scan time. A contrast bolus was injected in an antecubital vein at a flow rate of 5.0 ml/s followed by a saline chaser of 40 ml at 5.0 ml/s. Each tube provided 412 mAs/rot (maximum), and full X-ray tube current was given during 25–70% of the RR-interval. Exposure data were collected using the x-ray dosimetrical reports from DSCT and CCA.
Results:
The mean procedure time using DSCT and CCA was 16.1±4.7 min and 44.1±25.5 min (p<0.001), respectively. The mean contrast load in DSCT and CCA was 77.9±7.6 ml and 175.3±4.3ml (p<0.001), respectively. The overall radiation exposure for DSCT and CCA was calculated as 15.3±4.0 mSv and 5.7±4.3 mSv, respectively. Radiation exposure with DSCT was significantly lower (p<0.001) in patients with a heart rate of >70 bpm (12.9±3.1 mSv ) as compared with patients with heart rates <70 bpm (16.4±3.8 mSv).
Conclusion:
In today’s practice currently available DSCT scanners perform favorably as compared with CCA, considering procedure time and patient contrast load. Radiation exposure with DSCT remains higher but should not be considered a major disadvantage taking into account the relatively old age group that generally undergoes coronary angiography and the major benefit of not being exposed to the risks of an invasive procedure.
Comparison of Myocardial Bridging by Dual-Source CT With Conventional Coronary Angiography
