The value of calcium scoring in hypertensive patients as a referral criterion for the prediction of coronary artery disease detected on computed tomography coronary angiography

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Introduction The current national guidelines do not address the inequity between the increasing demand of Computed Tomography Coronary Angiography (CTCA) and the contrasting constrained imaging capacity. In a previous study we showed hypertension to be the strongest independent predictor of Coronary Artery Disease (CAD) detected on CTCA. In this study, the use of Coronary Calcium Scoring (CCS) for CTCA referrals is reviewed to identify the main parameters upon which CTCA referrals for the investigation of CAD, should be based. Methods After excluding TAVI and graft assessment patients, the individual electronic health records of 420 consecutive patients who underwent CTCA between July and November 2020, were reviewed with a mean age 59.1 years. Risk factors were recorded including smoking (23%), hyperlipidaemia (37%), positive family history (22%), systemic hypertension (51%), diabetes mellitus (30%) and male gender (50%). Referral criteria were also recorded for statistical analyses. Ethnicity, cardiac and past medical history were recorded. Patients were stratified into four groups according to CAD severity: absent, mild, moderate and severe disease, as seen on CTCA reports. The mean CCS for each CAD category was compared between hypertensive and non-hypertensive patients. Mean CCS were further compared in regard to the number of coronary arteries affected and the severity of CAD in each artery. Results Out of the total cohort, 247 (50.9%) patients were hypertensive. 249 (59.3%) CCS were interpreted in the very low risk category, 57 (13.6%) low risk, 58 (13.8%) moderate risk, 23 (5.48%) moderately high risk and 33 (7.86%) high risk. A significant difference in mean CCS and CAD severity was observed between mild, moderate and severe CAD (P = 0.015 and P < 0.001). Comparison of CCS between hypertensives and non-hypertensives, across the four CAD severity categories, revealed a significant difference in mean CCS in the severe CAD category (P = 0.013). Further comparison of CCS between hypertensives with chest pain and hypertensives without chest pain was non-significant. A higher number of affected coronary arteries was associated with a higher mean CCS and a significant difference in CCS was observed between hypertensives and non-hypertensives for the number of arteries affected. Similar results were observed when comparing mean CCS in moderate-severely affected coronary arteries. Conclusions Hypertensive patients with a high CCS were associated with higher incidence of severe CAD. Further, in those with hypertension, additional symptoms appear to have no effect on CCS. These results suggest that the incorporation of CCS in the investigation of CAD on CT angiography, may pose a powerful adjunct in proposing an alternative paradigm for the assessment of patients with hypertension and stable chest pain, in the progress of angiographic coronary disease.