Prognostic value of coronary computed tomography angiography in diabetic patients without chest pain syndrome.

Aims: Diabetic patients with coronary artery disease (CAD) are often free of chest pain syndrome. A useful modality for non-invasive assessment of CAD is coronary computed tomography angiography (CTA). However, the prognostic value of CAD on coronary CTA in diabetic patients without chest pain syndrome is relatively unknown. Therefore, the aim was to investigate the long-term prognostic value of coronary CTA in a large population diabetic patients without chest pain syndrome.

Methods: Between 2005 and 2013, 525 diabetic patients without chest pain syndrome were prospectively included to undergo coronary artery calcium (CAC)-scoring followed by coronary CTA. During follow-up, the composite endpoint of all-cause mortality, non-fatal myocardial infarction (MI), and late revascularization (>90 days) was registered.

Results: In total, CAC-scoring was performed in 410 patients and coronary CTA in 444 patients (431 interpretable). After median follow-up of 5.0 (IQR 2.7-6.5) years, the composite endpoint occurred in 65 (14%) patients. Coronary CTA demonstrated a high prevalence of CAD (85%), mostly non-obstructive CAD (51%). Furthermore, patients with a normal CTA had an excellent prognosis (event-rate 3%). An incremental increase in event-rate was observed with increasing CAC-risk category or coronary stenosis severity. Finally, obstructive (50-70%) or severe CAD (>70%) was independently predictive of events (HR 11.10 [2.52;48.79] (P = .001), HR 15.16 [3.01;76.36] (P = .001)). Obstructive (50-70%) or severe CAD (>70%) provided increased value over baseline risk factors.

Conclusion: Coronary CTA provided prognostic value in diabetic patients without chest pain syndrome. Most importantly, the prognosis of patients with a normal CTA was excellent.