BACKGROUND:
Coronary computed tomography angiography (CCTA) is a cost-effective and reliable non-invasive diagnostic tool with high sensitivity for detecting coronary artery disease (CAD). Guidelines recommend CCTA for patients with intermediate pretest probability of CAD. As the German Federal Joint Committee has included outpatient CCTA in statutory health insurance in 2024, further evaluation of the optimal patient cohort for CCTA is warranted.
METHODS:
This dual-center retrospective study included patients who underwent invasive coronary angiography following CCTA between January 2022 and January 2025 due to suspected or progressive CAD. CCTA findings were compared to results of coronary angiography to assess concordance and therapeutic relevance. Clinical, echocardiographic, and laboratory parameters were also analyzed.
RESULTS:
89 patients (mean age 70.6±10.3 years, 66.3% male) underwent coronary angiography after abnormal CCTA. Patients exhibited a high cardiovascular risk profile with arterial hypertension (84.3%), diabetes mellitus (32.6%), hypercholesterolemia (91.3%), elevated pretest probability (24.3±11.9%), and risk according to SCORE2 (12.6±7.9). CAD was previously diagnosed in 16.9% and prior myocardial infarction in 10.1%. CCTA demonstrated high sensitivity for detecting relevant stenoses (high-grade stenosis) of the left anterior descending artery (LAD) (95.9% [85.2%]), left circumflex artery (LCx) (80.0% [82.4%]), and right coronary artery (RCA) (92.1% [70.4%]), while specificity was moderate (LAD 27.5%, LCx 54.7%, RCA 64.0%). CCTA diagnosed CAD more often than angiography in the LAD (85.4% vs. 55.1%, p<0.01), LCx (59.1% vs. 40.4%, p<0.01), and RCA (60.2% vs. 43.8%, p<0.01). For severe disease, detection rates were higher for the LAD (51.7% vs. 30.3%, p<0.01) and LCx (35.2% vs. 19.1%, p<0.01), but not RCA (37.5% vs. 30.3%, p=0.29). Significant left main coronary artery (LM) disease was found in one patient but not confirmed invasively. CCTA identified high-grade stenoses in 69.7%, while 30.3% had non-high-grade lesions. Patients with high-grade stenosis had more often typical angina pectoris (19.4% vs. 11.1%, p=0.34) and a higher SCORE2 (14.2±8.4 vs. 9.5±5.9, p=0.01). Revascularization (coronary intervention or coronary artery bypass graft) was necessary in 49.4% of all patients, and more often in patients with high-grade stenosis in CCTA (61.3% vs. 22.2%, p<0.01). These patients also more often reported typical angina pectoris (25.0% vs. 8.9%, p=0.04), while risk factors and scores did not differ. No treatment was recommended in the remaining 50.6% of patients (38.7% of patients with suspected high-grade stenosis and 77.8% without high-grade stenosis in CCTA).
CONCLUSION:
This real-world cohort of patients with suspected or known CAD all underwent invasive coronary angiography after CCTA, but only half ultimately required coronary revascularization. Notably, one-third underwent coronary angiography despite the absence of high-grade stenosis in CCTA. These findings highlight that clinical decision-making extends beyond imaging results and is strongly influenced by clinical judgment, symptoms, and cardiovascular risk. CCTA demonstrated high sensitivity but moderate specificity, often overestimating stenosis severity, which underscores the need for careful patient selection and integration of clinical context.
