Figure 1

For all acquisitions the pulse sequence recorded in real-time the actual duration of each RR interval during scanning from which an instantaneous heart rate is determined. The variation in this beat-by-beat heart rate as a percentage of the fixed heart rate determined at the scan prescription stage is plotted as a function of heart beat number during the scan. Data for SMART1Map (o's) and MOLLI (x's) are shown and demonstrate heart rate variations can reach 20% across even these short breath-held scans.