Diagnostic accuracy of computed tomography coronary angiography in patients with high heart rates: a systematic review

Abstract

Introduction: An understanding of the diagnostic accuracy of computed tomography coronary angiography (CTCA) is critical for clinicians and guideline developers to determine the appropriate use and position of the scan in the diagnostic pathway. Current imaging guidelines, which are based on evidence from non-contemporary CT technology, only recommend the routine use of CTCA in patients with low heart rates (HR). The aim of this systematic review was to investigate the diagnostic accuracy of CT coronary angiography using state-of-the-art scanner technology, in comparison with invasive coronary angiography, for patients with high HRs. Methods: Methods for the systematic review were determined a priori, based on a previously published protocol. A systematic search of PubMed, CINAHL, Embase and Scopus was performed as well as a search of unpublished sources and reference lists. Titles and abstracts were screened by two independent reviewers. Full-text screening was then performed on all studies that met the criteria for inclusion in the systematic review at the title and abstract level. Studies were included that described diagnostic accuracy metrics in patients with high HR. Studies that did not compare CTCA to invasive coronary angiography were excluded. Only current generation scanners with greater than 128 detectors were included. Included studies underwent critical appraisal using the QUADAS-2 tool. All critically appraised studies were then included in the final review regardless of methodological quality. Data extraction was then undertaken and the results were collated and analysed through narrative synthesis and a diagnostic test accuracy meta-analysis. Results: Twelve studies were included in the systematic review; 11 of these studies were also included in a diagnostic test accuracy meta-analysis. Meta-analysis indicated high level pooled sensitivity 99% (95% CI: 97%,100%) in CTCA at high HR. Pooled specificity was lower at 79% (95% CI: 72%, 85%). Diagnostic accuracy performed better at artery level (pooled sensitivity 96% (95% CI: 93%, 97%) and pooled specificity 93% (95% CI: 90%, 96%)); and segment level (pooled sensitivity 91% (95% CI: 88%, 93%) and pooled specificity 96% (95% CI 95%, 98%)). The prevalence of clinically significant coronary artery disease was high in each of the included studies. There were insufficient data to effectively evaluate the accuracy of CTCA at individual HRs. No significant difference was evident between different CT makes and models included in the review in terms of diagnostic accuracy. Conclusion: Diagnostic sensitivity of CTCA is high at elevated HRs. Consequently, CTCA can still be performed when standard HR control is contraindicated or ineffective as it is an effective test to rule out coronary artery disease. However, the modest results for sensitivity indicate a positive result should be assessed with caution. Implications for Practice: CT scanning is still appropriate in patients with high HRs when contraindications to HR lowering medications exist or are ineffective and when the CTCA is performed in order to rule out rather than quantify coronary artery stenosis. Implications for Future Research Further research is required to better understand the effect high HRs have on important patient outcomes, such as over-testing and anxiety related to false negative results.