Motion artifacts on coronary CT angiography images in patients with a pericardial effusion

Abstract

BackgroundPatients with a pericardial effusion can have a pendulum-like movement of the heart. No reports associate the presence of pericardial fluid with coronary CT angiography (CTA) images that are degraded by motion artifact. ObjectiveWe tested the hypothesis that patients with pericardial effusion have coronary CTA images compromised by motion artifacts, even when other known causes of motion artifact in coronary imaging are minimized. MethodsAmong the prospectively electrocardiogram-gated single heart beat 320-detector row coronary CTA studies performed from September 2009 to May 2013, 13 consecutive studies acquired with a heart rate <60 beats/min that indicate a pericardial effusion formed an effusion cohort. A control cohort included 13 studies with no pericardial fluid performed by the same CT scanner; these were pair-matched to the effusion cohort for heart rate, sex, age, and body mass index. All studies were free of arrhythmia and respiratory motion. Motion artifact was separately assessed (3-point scale) at 8 coronary segments by 2 cardiovascular imaging teams. ResultsThe mean pericardial effusion volume for the effusion cohort was 129 ± 57 mL (range, 39–222 mL). Intra-observer/interobserver reproducibility of the motion artifact scores were good (κ = 0.636–0.791). Motion artifacts were more frequently observed in the effusion cohort for the left circumflex (no, mild, severe artifact, 54%, 46%, 0% vs 81%, 19%, 0%, respectively, for effusion vs control; P = .039) and right coronary arteries (no, mild, severe artifact = 41%, 44% 15% vs 79%, 21%, 0%, respectively, for effusion vs control; P < .001), especially for the middle or distal segments. Larger effusion volumes were associated with more severe motion artifacts. ConclusionPatients with pericardial effusion have coronary CTA images compromised by cardiac motion artifacts, particularly in the left circumflex and right coronary arteries.