Site vs. core laboratory variability in computed tomographic angiography-derived SYNTAX scores in the SYNTAX III trial.

AIMS: To investigate the variability between site and core laboratory (CL) calculation of the anatomical SYNTAX score (SS) based on coronary computed tomography angiography (CTA) alone and functional SS based on coronary CTA and fractional flow reserve derived from computed tomography (FFRCT) in the SYNTAX III trial. METHODS AND RESULTS: The SYNTAX III trial was a multicentre, international study that included 223 patients with three-vessel disease with or without left main involvement. Functional SS was computed by subtracting non-flow limiting stenoses (FFRCT > 0.80) from anatomical SS. SS was combined with clinical information to generate the SYNTAX score II (SS II) that provides treatment recommendations. The mean anatomical SS based on coronary CTA alone was 33.4 ± 12.7 by sites and 37.1 ± 13.4 by CL (P < 0.001). The mean functional SS based on coronary CTA and FFRCT was 30.5 ± 13.0 by sites and 33.3 ± 13.6 by CL (P < 0.001). The intraclass correlation coefficient was 0.49 [95% confidence interval (CI) 0.37-0.59) in anatomical SS and 0.62 (95% CI 0.52-0.70) in functional SS. The Cohen's κ comparing treatment recommendation between sites and CL was 0.68 (95% CI 0.58-0.78) based on anatomical SS and 0.71 (95% CI 0.60-0.82) based on functional SS. CONCLUSION: The mean anatomical SS derived from coronary CTA alone and functional SS based on coronary CTA and FFRCT were higher when assessed by the CL than by the sites themselves. However, substantial agreement in treatment recommendation by SS II between sites and CL was demonstrated. CLINICAL TRIALS.GOV IDENTIFIER: NCT02385279.

Long-term prognostic utility of computed tomography coronary angiography in older populations.

AIMS: The long-term prognostic value of coronary computed tomography angiography (CCTA)-identified coronary artery disease (CAD) has not been evaluated in elderly patients (≥70 years). We compared the ability of coronary CCTA to predict 5-year mortality in older vs. younger populations. METHODS AND RESULTS: From the prospective CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter) registry, we analysed CCTA results according to age <70 years (n = 7198) vs. ≥70 years (n = 1786). The severity of CAD was classified according to: (i) maximal stenosis degree per vessel: none, non-obstructive (1-49%), or obstructive (>50%); (ii) segment involvement score (SIS): number of segments with plaque. Cox-proportional hazard models assessed the relationship between CCTA findings and time to mortality. At a mean 5.6 ± 1.1 year follow-up, CCTA-identified CAD predicted increased mortality compared with patients with a normal CCTA in both <70 years [non-obstructive hazard ratio (HR) confidence interval (CI): 1.70 (1.19-2.41); one-vessel: 1.65 (1.03-2.67); two-vessel: 2.24 (1.21-4.15); three-vessel/left main: 4.12 (2.27-7.46), P < 0.001] and ≥70 years [non-obstructive: 1.84 (1.15-2.95); one-vessel: HR (CI): 2.28 (1.37-3.81); two-vessel: 2.36 (1.33-4.19); three-vessel/left main: 2.41 (1.33-4.36), P = 0.014]. Similarly, SIS was predictive of mortality in both <70 years [SIS 1-3: 1.57 (1.10-2.24); SIS ≥4: 2.42 (1.65-3.57), P < 0.001] and ≥70 years [SIS 1-3: 1.73 (1.07-2.79); SIS ≥4: 2.45 (1.52-3.93), P < 0.001]. CCTA findings similarly predicted long-term major adverse cardiovascular outcomes (MACE) (all-cause mortality, myocardial infarction, and late revascularization) in both groups compared with patients with no CAD. CONCLUSION: The presence and extent of CAD is a meaningful stratifier of long-term mortality and MACE in patients aged <70 years and ≥70 years old. The presence of obstructive and non-obstructive disease and the burden of atherosclerosis determined by SIS remain important predictors of prognosis in older populations.