Biventricular and biatrial assessment using low-dose cine computed tomography during recirculation phase of contrast agent: Comparison to cine cardiac magnetic resonance.

BACKGROUND: The purpose of this study was to evaluate the accuracy of biventricular and biatrial volume and function measurements by low-dose cardiac cine computed tomography (CT) during recirculation phase of contrast agent with cine cardiac magnetic resonance (CMR) as the reference standard.

METHODS: Thirty patients who underwent low-dose cine CT on a third-generation dual-source CT scanner within 30 days of CMR were retrospectively studied. Left and right ventricular (LV, RV) end-diastolic volume (EDV) and end-systolic volume, stroke volume, ejection fraction (EF), and LV mass were measured using the Simpson's method on short-axis images. Left and right atrial (LA, RA) maximum volume, minimum volume, and emptying fraction were measured using the biplane area-length method on 2-chamber and 4-chamber images (LA) and area-length method on 4-chamber images (RA).

RESULTS: All low-dose cine CT-derived parameters strongly correlated with those from CMR (r ​= ​0.771-0.974). Mean differences (limits of agreement) between low-dose cine CT and CMR were small for LV EDV (10.0 ​mL [-17.9 to 38.0]), LV EF (-0.4% [-9.5 to 8.6]), and RV EF (0.8% [-7.4 to 8.9]), as well as for atrial volumes and emptying fractions. All low-dose cine CT measurements also showed excellent intra- and inter-rater reproducibility. The median effective radiation dose for the low-dose cine CT was 0.85 ​mSv.

CONCLUSION: Low-dose cine CT during recirculation phase of contrast agent provides accurate, reproducible quantification of biventricular and biatrial volume and function compared with cine CMR as the reference, while achieving substantial radiation dose reduction without requiring additional contrast agent.