Prevalence and severity of coronary artery disease in asymptomatic military air crew in the Netherlands: a prospective, cross-sectional study (SUSPECT)

OBJECTIVE: Coronary artery disease (CAD) is a main cause of incapacitating adverse cardiac events in aviation. Military aircrew ≥40 years in the Netherlands undergo a 5-year exercise ECG (X-ECG), which lacks precision to identify relevant CAD. The study aim was to identify the screening value of cardiac CT (CCT) in asymptomatic military aircrew. DESIGN: Prospective, single-centre, cross-sectional study. SETTING: Conducted at the Centre for Man in Aviation, Royal Netherlands Air Force. CT scans were performed at the University Medical Centre, Utrecht. PARTICIPANTS: Asymptomatic military aircrew ≥40 years were asked to undergo CCT, with coronary artery calcium score (CACS) and coronary CT angiography (CCTA), following their aeromedical exam. CCT was performed in 211 participants (median age 49.3 years (43.6-52.8), 98% men, 65% pilots). OUTCOME MEASURES: The main objective was to determine the prevalence of relevant CAD. Clinically relevant CAD (CR-CAD) is defined as CACS ≥100 and/or a stenosis ≥50%. Aeromedically relevant CAD (AR-CAD) includes CR-CAD and/or a left main stenosis >30% or an aggregate stenosis ≥120%. Secondary objectives included assessing the prevalence of mild coronary stenosis (defined as 25%-49% stenosis), the presence of high-risk plaque (HRP) features and CCT safety. RESULTS: CR-CAD was found in 25 male aircrew (12%), with a CACS of ≥100 in 21 (10%) and a stenosis ≥50% in 10 (5%), including two with CACS 0. Two additional men had ≥120% aggregate stenosis, bringing total AR-CAD to 27 (13%). Twenty-nine men (14%) had mild stenosis. HRP features were present in 44 (21%). There were no CT-related complications. Of 196 participants who underwent X-ECG, seven showed abnormal results; one had relevant CAD. CONCLUSIONS: Contrast-enhanced CCTA provides additional information both on high-risk features and obstructive CAD compared with CACS only. CCT is safe and is of additional value to X-ECG in a low-risk population with a high-hazard occupation. TRIAL REGISTRATION NUMBER: NCT05508893.