Prospective ECG triggering reduces prosthetic heart valve-induced artefacts compared with retrospective ECG gating on 256-slice CT

Abstract

Objectives Multidetector computed tomography (MDCT) has diagnostic value for the evaluation of prosthetic heart valve (PHV) dysfunction but it is hampered by artefacts. We hypothesised that image acquisition using prospective triggering instead of retrospective gating would reduce artefacts related to pulsating PHV. Methods In a pulsatile in vitro model, a mono- and bileaflet PHV were imaged using 256 MDCT at 60, 75 and 90 beats per minute (BPM) with either retrospective gating (120 kV, 600 mAs, pitch 0.2, CTDI vol 39.8 mGy) or prospective triggering (120 kV, 200 mAs, CTDI vol 13.3 mGy). Two thresholds (>175 and <0.03) but not at 90 BPM. Conclusions Compared with retrospective gating, prospective triggering reduced most artefacts related to pulsating PHV in vitro. Key Points • Computed tomographic images are often degraded by prosthetic heart valve-induced artefacts • Prospective triggering reduces prosthetic heart valveinduced artefacts in vitro • Artefact reduction at 90 beats per minute occurs without image noise reduction • Prospective triggering may improve CT image quality of moving hyperdense structures. © European Society of Radiology 2012.