Highly Accelerated Real-time Cine MRI Pulse Sequence for Cardiac Implantable Electronic Devices and Arrhythmias

Purpose To compare the image quality and temporal resolution of a 32-fold accelerated real-time cine MRI pulse sequence (19.3-msec temporal resolution) with those of a previously described 16-fold accelerated Cartesian real-time cine sequence (39.8-msec temporal resolution) in patients with cardiac implantable electronic devices (CIEDs) and arrhythmias. Materials and Methods This retrospective study included patients with CIEDs and arrhythmias scanned using both radial and Cartesian real-time cine MRI pulse sequences with gradient-recalled echo readouts at 1.5 T from March 2022 to March 2024. Image quality was assessed visually by clinical raters using a five-point Likert scale for each of four categories (namely, conspicuity, temporal fidelity of wall motion, artifact, and noise) and quantitatively using the signal-to-noise-and-artifact ratio metric. The authors used the Wilcoxon signed rank test and paired <i>t</i> test to compare differences for non-normally and normally distributed variables, respectively. Results The study included 23 patients with CIEDs and arrhythmias (nine female and 14 male patients; mean age, 66.5 years ± 13.3 [SD]). The radial real-time cine sequence yielded significantly higher median summed visual scores than the Cartesian real-time cine sequence across all myocardial segments (radial, 17.5-18, Cartesian, 14.5-16; <i>P</i> < .001). The mean signal-to-noise-and-artifact ratio was significantly higher for radial than for Cartesian (radial, 18.3 ± 5.6, Cartesian, 9.4 ± 4.1; <i>P</i> < .001). Conclusion The proposed 32-fold accelerated radial real-time cine MRI pulse sequence provided higher temporal resolution and superior image quality than the 16-fold accelerated Cartesian real-time cine pulse sequence in patients with CIEDs and arrhythmias. <b>Keywords:</b> MR Imaging, Cardiac, Heart, Left Ventricle, Right Ventricle, Artifacts, Cardiac Assist Devices, Imaging Sequences, Radial K-Space, CIED, Arrhythmia, GRASP, Compressed Sensing, Real-Time, Freebreathing <i>Supplemental material is available for this article.</i> © RSNA, 2025.