Abstract 14849: Incremental Prognostic Value of Coronary CT Angiography over Coronary Calcium Score in Symptomatic Patients with Suspected Coronary Disease: Results from the CONFIRM Registry (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter Registry)
Background: While the prognostic value of coronary calcium scoring (CCS) has been well established in asymptomatic individuals, it is also commonly performed at the time of coronary computed tomographic angiography (CCTA) examinations. Whether CCTA findings of CAD adds incremental prognostic value over CCS in symptomatic individuals remains inadequately explored.
Methods: A total of 9231 symptomatic patients (4583 (50%) men, age 56±12years) without known history of CAD from an international multicenter CCTA registry underwent both CCS and CCTA. Patients were considered symptomatic if they had chest discomfort or dyspnea. CCTAs were graded for per-patient maximal obstructive CAD (>70% stenosis), and by a segment involvement score [SIS] (which summates the number of coronary segments exhibiting any CAD [score range 0-16]). Patients were followed up for a median duration of 24 months (Interquartile Range 17-40 months) for a composite endpoint of all cause mortality and nonfatal myocardial infarction (D/MI). Multiple nested Cox proportional hazard models were used to determine the incremental prognostic value of CCTA over CCS (included as a continuous variable).
Results: A total of 822 (9%) and 749 (8%) patients had CCS>400 and obstructive CAD on CCTA respectively. At follow-up, 152 patients experienced D/MI. In these symptomatic patients, CCS offered improved discriminatory ability beyond traditional Framingham risk scoring (FRS) (area under the receiver operator characteristics curve [AUC] 0.716 vs. 0.682, p<0.0001). When added sequentially to FRS and CCS, CCTA findings of obstructive CAD (0.779, p=0.01), Duke CAD prognostic index (0.781, p<0.0001), and SIS (0.787, p=0.04) improved discrimination of patients at risk for D/MI (Figure).
Conclusion: In symptomatic patients with suspected CAD, CCTA adds incremental prognostic value over and above conventional risk scoring and CCS.
- © 2011 by American Heart Association, Inc.