ECG-gated coronary angiography enables submillisievert imaging in invasive cardiology

Background The median dose area products (DAP) and effective doses (ED) of patients arising from coronary angiography (CA) are considerable: According the 2013 National German Registry, they amount to 19.8 Gy × cm 2 and 4.0 mSv, respectively. Methods We investigated the feasibility of prospective electrocardiogram (ECG)-gated coronary angiography (CA)—a novel technique in invasive cardiology—with respect to possible reduction in irradiation effects. Instead of universally fix-rated radiographic acquisition within 7.5–15 frames/s, one single frame/heartbeat was triggered toward the diastolic moment immediately before atrial contraction (77 % of ECG-RR interval) most likely to provide motion-free and hence optimized resolution of the coronary tree. For 200 patients (body mass index 27.8 kg/m 2 , age 67.5 years, male 55 %, 68 bpm) undergoing ECG-gated CA, we measured various median (interquartile range) parameters for radiation exposure. Results The total DAP was 0.64 (0.46–1.00), radiographic fraction was 0.30 (0.19–0.43), and fluoroscopic fraction was 0.35 (0.21–0.57) Gy × cm 2 . Radiographic imaging occurred within 21.7 s (17.1–26.3), with 25 frames (20–30) over the course of 7 runs (6–8). Fluoroscopy time was 119 s (94–141). Radiographic DAP was 12.6 mGy × cm 2 /frame and 13.8 mGy × cm 2 /s. Fluoroscopic DAP was 0.8 mGy × cm 2 /pulse and 3.1 mGy × cm 2 /s. Patient reference point air kerma was 17.0 mGy (11.1–28.1) and contrast volume was 70 ml (60–85). Conclusion In conclusion, invasive ECG-gated coronary imaging is feasible in clinical routine and enables patient EDs of approx. 3 % of typical values in invasive cardiology: 0.13 mSv (0.09–0.20).