Background: There is uncertainty regarding the best measure for prediction of long term outcome following coronary CT angiography (CCTA).
Methods: We evaluated predictors of death or myocardial infarction (MI) (MACE) over 8.0±4.3 yrs following 64-slice CCTA and coronary artery calcium (CAC) score in 400 pts (age 58±13 yrs, 38% female) with chest pain but without previously known coronary artery disease (CAD). CAD was assessed as presence of any luminal obstruction ≥50% (Obstruction), total number of coronary arterial segments with atheroma (All Segs), number of proximal segments with ≥50% luminal stenosis (Prox Segs), and total CAC score (Agatston method). Outcome predictors were examined using Cox univariate and multivariate regression analysis.
Results: MACE occurred in 64 pts (death in 51, non-fatal MI in 19). Univariate CCTA predictors of MACE were Obstruction, All Segs, Prox Segs and CAC and clinical predictors were age and diabetes mellitus. After adjustment for age, gender and diabetes, CAC remained a significant independent predictor of MACE (Table).
Conclusions: In symptomatic pts undergoing 64-slice CCTA, several measures of CAD were associated with 8 year MACE. However, CAC which reflects total burden of calcified coronary atheroma, was the only independent CT predictor of long term outcome after adjustment for clinical risk.
