Abstract 342: Usefulness of Coronary CT Angiography in Patients With Suspected Coronary Artery Disease and a Positive Exercise Test
Objective: Functional testing is a cornerstone in the diagnostic evaluation of patients with suspected significant coronary artery disease (CAD). However, a suboptimal diagnostic specificity of exercise ECG testing (exECG) may result in unnecessary invasive coronary angiography (CAG). We evaluated the diagnostic impact of coronary CT angiography (CTA) in patients with suspected CAD and a positive exECG.
Material and methods: CTA and CAG were performed in 63 patients with suspected CAD due to chest pain and a positive exECG. A positive stress test was defined as the development of horizontal or descending ST-depression ≥ 1mV measured 80ms from the J point, typical chest pain, ventricular arrhythmia (>3 sustained premature ventricular beats), and/or >20 mmHg drop in systolic blood pressure. A positive CTA was defined as a coronary lumen reduction ≥ 50%, or the presence ≥ 1 non-evaluable coronary segments with quantitative CAG as reference (≥ 50% lumen reduction).
Results: Mean (SD) age was 62 (±8) years, 48% of the patients were men. Four, 33 and 26 patients had low, intermediate or high pretest likelihood of significant CAD, respectively. The prevalence of significant CAD was 32%. CTA diagnostic sensitivity (95% confidence interval) was 100% (83–100), specificity 81% (67–92), positive predictive value 71% (51–89) and negative predictive value 100% (90–100). Significant CAD was excluded by CTA in 35 of 63 (55%) patients with a positive exECG (figure⇓).
Conclusion: In patients with suspected CAD and a positive exercise ECG test, coronary CT angiography seems efficient in ruling-out significant CAD.