Feasibility of Dual-Source Cardiac CT Angiography with High-Pitch Scan Protocols

OBJECTIVES: Cardiac CT angiography (CCTA) has become a frequently used diagnostic tool in clinical practice, but concern remains about the radiation exposure. Because of the second x-ray acquisition system, dual-source CT systems might allow for high-pitch CT data acquisition and thus for examination of the whole heart during a single heart beat, with the potential for radiation dose reduction. We assessed the feasibility of a high-pitch scan mode with a dual-source CT system.

METHODS: High-pitch modes were used in patients undergoing CCTA with a dual-source CT system. Diagnostic image quality for cardiac structures and coronary arteries was assessed. Radiation dose was estimated from the scanner-generated dose-length product (DLP).

RESULTS: CCTA was performed in 14 patients during a single heart beat applying a pitch value of 3.4. Mean heart rate during examination was 56.4+/-8.1 beats/min. Diagnostic image quality for the assessment of larger cardiac structures was obtained in all patients, whereas diagnostic image quality could be achieved in 82% of all coronary segments. With a mean DLP of 145+/-47 mGy x cm, the resulting estimated radiation dose was 2.0+/-0.7 mSv.

CONCLUSIONS: This proof-of-concept study shows the ability of dual-source CT scanners to scan the whole heart during one single heart beat at low radiation dose.

PMID: 19577211

Posted in Computed Tomography and tagged , .


  1. This is an important concept, which has become possible with dual-source technology. Stay tuned!

  2. High-pitch CTA has real potential for vascular imaging – even without ECG-gating. Very fast, Very low dose.

  3. This is a very innovative concept giving a different use to the second beam source in DSCT. This proof-of-concept shows the capacity of the scanner to create diagnostic cardiac images (not necessarily of the coronaries) minimizing the radiation dose – however, at the expense of the temporal resolution. This technique appears very promising for the younger patient with a low suspicion of CAD and a low regular heart rate.

  4. This is a proof of concept study and the results apply to the FLASH scanner. This is what makes the FLASH scanner so fast.

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