Introduction: A family history of premature CAD may promote enhanced development of coronary atherosclerosis in a sibling population. Baseline CV algorithms may underestimate the risk of coronary incidents in individuals at familial risk. Cardiac CT provides high diagnostic performance for the detection of coronary plaques. There is little data on the use of this technology in the initial diagnostic approach of these patients. The prognostic value of early detection of coronary plaques by cardiac CT remains unknown in this population.
Objectives: The study aimed to estimate the global CV risk and the pre-test probability of CAD in patients with a family history of premature CAD. We investigated the potential role of cardiac CT imaging in the assessment of coronary risk in patients from high-risk families. We sought to remind the 2019 ESC guidelines for screening for CAD in asymptomatic subjects.
Methods: Fifty siblings of patients with premature CAD were investigated. The pre-test probability of CAD was determined with the Clinical Model of the CAD consortium. The risk of CV disease was calculated and compared with three different risk algorithms (SCORE, FRS, PROCAM). All patients underwent cardiac CT with both non-contrast and contrast imaging. Coronary artery calcium (CAC) scoring was calculated and CT angiograms were analyzed. Patients with suspected CT obstructive CAD underwent coronary angiography. Clinical outcomes in terms of treatment were analyzed.
Results: The pre-test probability of CAD was low: CAD consortium <10% in 60%, SCORE <5% in 100%, FRS <10% in 88%, CAC scoring <100% in 68%. However, PROCAM was <10% in 16 cases (32%). Only 12 patients (24%) presented normal CCTA findings. In patients with abnormal CCTA findings (n = 38), PROCAM was higher than FRS in 20 patients (53%). Coronary angiography was performed in 31 cases (62%) for suspected CT obstructive CAD. Most patients presented no significant lesions (55%). Revascularization was performed in 8 patients (16%), 6 of them (75%) presented CAC scoring <100, 4 of them (50%) presented CAC scoring <400. After investigation, lipid-lowering therapy was enhanced by 66%.
Conclusion: Coronary atherosclerotic-phenotyping using cardiac CT may provide discriminatory information allowing earlier identification of patients at familial risk of premature CAD. This diagnostic workup strategy may help to guide and improve the management of these patients. However, there is a paucity of data concerning the prognostic significance of this technology in relatives at familial risk of premature CAD. Therefore, further randomized controlled trials are needed to assess the incremental risk-predictive value of this approach in this population.
Keywords: Coronary atherosclerosis; cardiac computed tomography; cardiovascular risk assessment; coronary artery calcium scoring.