Abstract 307: Incremental Prognostic Significance of Left Ventricular Dysfunction to Coronary Artery Disease Detection by 64-Detector Row Coronary Computed Tomographic Angiography for the Prediction of All-Cause Mortality: Results From a Two-Center Study of 5,646 Patients
Background: Early reports suggest a potential prognostic value of coronary artery disease (CAD) detection by coronary computed tomographic angiography (CCTA), although these studies have been limited by small samples in single centers. Further, the incremental prognostic value of left ventricular ejection fraction (EF) above and beyond CAD detection by CCTA has not been assessed.
Methods: We evaluated 5,646 consecutive adults with suspected CAD undergoing CCTA at two centers without prior CAD. Luminal diameter stenosis severity by CCTA was graded as none (0%), mild (1– 49%), moderate (50 – 69%) or severe (>70% stenosis) for each coronary artery. 2.3±0.7 year follow-up of all-cause mortality was evaluated using multivariate and Cox proportional hazards models. In risk-adjusted models, patient demographics and traditional CAD risk factors were included. During follow-up, 115 deaths occurred (2.0%). Deaths were verified by the Social Security Death Iindex.
Results: In risk-adjusted models, CCTA detection of any severe CAD of luminal stenosis >70% predicted all-cause death (hazards ratio [HR] 2.31, 95% confidence interval [CI] 1.55–3.44, p<0.001). In comparison to individuals without severe CAD, increased risk of death was identified for those with severe one- (8.8%), two- (8.6%) and three- (18.3%) vessel CAD (p<0.001 for comparison). Importantly, in comparison to the presence of any CAD by CCTA, the absence of CAD was associated with very low rates of death during the follow-up period (0.43% vs. 1.22%, p50%, those with EF<50% exhibited a trend towards higher rates of death (HR 1.45, 95% CI 0.97–2.15, p=0.069). The presence of reduced EF<50% revealed significant interaction with severe CAD for incremental prediction of risk of all-cause mortality (p<0.001). The annualized mortality rate in individuals with 50% was very low (0.65%), and increased accordingly for individuals with 50% (1.74%); and >70% luminal stenosis and EF<50% (4.30%) [log-rank test p<0.001].
Conclusions: In a large two-center cohort, severe CAD detection by CCTA predicted incident death by the absolute presence of as well as increasing number of vessels with severe CAD. The addition of EF measures by CCTA enhanced risk prediction of death in individuals with severe CAD.