Multidetector computed tomography angiography evaluation of coronaries arteries with intracycle motion correction algorithm

Abstract

Purpose: Multidetector computed tomography coronary angiography (MDCT-CA) is a reliable diagnostic modality for evaluating patients with suspected CAD, with high diagnostic performance for the detection of significant coronary lesions. However, previous multicenter studies have documented lack in the MDCT-CA diagnostic performance in case of high heart rate (HR), large coronary calcification and severely elevated body mass index. Coronary arterial motion is one of the most common limitations reported, with up to 12% of coronary artery segments judged as non-evaluable. Motion artifacts are more pronounced at higher heart rates and irregular heart rhythms. Among the numerous technological solutions offered to reduce motion artifact, a novel vendor-specific motion-correction (MC) algorithm, the IntraCycle Motion Correction SnapShot Freeze (SSF), has been developed. The method utilizes information from adjacent cardiac phases within a single cardiac cycle to characterize and compensate for coronary motion. The aim of the study was to compare the global evaluability and image quality score of MDCT-CA with SSF to standard (STD) reconstructions. Methods: 60 patients with HR variability > 5 bpm during the scanning irrespective of HR before scanning or with HR before the scanning > 70 bpm were enrolled in our study (mean age 65,8±10,7 years, 41 males). MDCT-CA studies for both SSF and STD reconstructions have been presented to two blinded readers in random sequence. The number of artifacts, sub-analysis of the type of artifacts, image quality score and global evaluability of coronaries were compared in the 2 groups. Results: In 45 patients iv metoprolol (average dose 14±7.7 mg) has been administered before scanning. The average HR during the scan was 70±9 bpm. The post-processing with SSF in comparison to STD showed a significant lower number of severe artifacts (27 vs 178, p<0.0001) and slice misalignement artifacts (8 vs 143, p<0.0001), an improvement of image quality score (356 segments judged as excellent vs 129, p<0.0001) and of global coronary evaluability (97% vs 80.6%, p<0.0001). Conclusions: Use of MC algorithm SSF facilitate improvements in image quality and global coronary evaluability in patients with high and variable HR