Diagnostic performance of cardiac imaging methods to diagnose ischaemia-causing coronary artery disease when directly compared with fractional flow reserve as a reference standard: A meta-analysis

Aims The aim of this study was to determine the diagnostic performance of single-photon emission computed tomography (SPECT), stress echocardiography (SE), invasive coronary angiography (ICA), coronary computed tomography angiography (CCTA), fractional flow reserve (FFR) derived from CCTA (FFR_CT), and cardiac magnetic resonance (MRI) imaging when directly compared with an FFR reference standard. Method and results PubMed andWeb of Knowledge were searched for investigations published between 1 January 2002 and 28 February 2015. Studies performing FFR in at least 75% of coronary vessels for the diagnosis of ischaemic coronary artery disease (CAD) were included. Twenty-three articles reporting on 3788 patients and 5323 vessels were identified. Meta-analysis was performed for pooled sensitivity, specificity, likelihood ratios (LR), diagnostic odds ratio, and summary receiver operating characteristic curves. In contrast to ICA, CCTA, and FFR_CT reports, studies evaluating SPECT, SE, and MRI were largely retrospective, single-centre and with generally smaller study samples. On a per-patient basis, the sensitivity of CCTA (90%, 95% CI: 86-93), FFR_CT (90%, 95% CI: 85-93), and MRI (90%, 95% CI: 75-97) were higher than for SPECT (70%, 95% CI: 59-80), SE (77%, 95% CI: 61-88), and ICA (69%, 95% CI: 65-75). The highest and lowest perpatient specificity was observed for MRI (94%, 95% CI: 79-99) and for CCTA (39%, 95% CI: 34-44), respectively. Similar specificities were noted for SPECT (78%, 95% CI: 68-87), SE (75%, 95% CI: 63-85), FFR_CT (71%, 95% CI: 65-75%), and ICA (67%, 95% CI: 63-71). On a per-vessel basis, the highest sensitivity was for CCTA (pooled sensitivity, 91%: 88-93), MRI (91%: 84-95), and FFR_CT (83%, 78-87), with lower sensitivities for ICA (71%, 69-74), and SPECT (57%: 49-64). Per-vessel specificity was highest for MRI (85%, 79-89), FFR_CT (78%: 78-81), and SPECT (75%: 69-80), whereas ICA (66%: 64-68) and CCTA (58%: 55-61) yielded a lower specificity. Conclusions In this meta-analysis comparing cardiac imaging methods directly to FFR, MRI had the highest performance for diagnosis of ischaemia-causing CAD, with lower performance for SPECT and SE. Anatomic methods of CCTA and ICA yielded lower specificity, with functional assessment of coronary atherosclerosis by SE, SPECT, and FFR_CT improving accuracy.