Diagnostic accuracy of prospectively gated, 128‐slice or greater CTCA at high heart rates: a systematic review and meta‐analysis

INTRODUCTION: Prospectively gated 64‐slice CT coronary angiography (CTCA) may be contraindicated for heart rates (HRs) over 65 beats per minute (bpm) due to reduced diagnostic sensitivity. Newer CT scanners typically provide 128 or more slices and superior temporal resolution compared with older models; consequently, diagnostic accuracy for current technology prospectively gated CTCA may be adequate at HRs above 65 bpm. The aim of this systematic review was to investigate the diagnostic accuracy of CTCA using 128‐slice or greater CT technology when compared with conventional coronary angiography for patients with HRs >65 bpm. METHODS: A systematic search of PubMed, CINAHL, EMBASE and Scopus was performed as well as unpublished databases, sources and reference lists. Titles and abstracts were screened by two independent reviewers. Full‐text screening was then performed. Studies that determined diagnostic accuracy of coronary artery stenosis in adult patients with high heart rates utilising prospectively gated 128 detector or greater scanners were included. Studies that were included in the review underwent critical appraisal using the QUADAS‐2 tool. RESULTS: Ten studies were included in the systematic review, with nine of these included in a diagnostic test accuracy meta‐analysis, including six of which reported data at the patient level. Meta‐analysis indicated very high pooled sensitivity 100% (95% CI 0.99, 1.00); however, pooled specificity was less at 79% (95% CI 0.69, 0.88). CONCLUSIONS: Prospectively gated CT coronary angiography may be justifiable at heart rates above 65 bpm if performed on a 128‐slice or greater CT unit. Caution regarding the implication of a positive result is recommended due to reduced specificity. Further evidence is required before consideration of a new higher heart threshold.