Effects of β-blocker Administration on Cardiac Function: A CoronaryComputed Tomography Angiography Study

BACKGROUND: β-blockers are widely used for lowering heart rate (HR) during coronary computed tomography angiography (CCTA); however, they should be used with caution for patients with heart failure as they may have a negative inotropic effect. OBJECTIVE: To clarify the effects of β-blockers (oral and intravenous injection) on cardiac function using CCTA. METHODS: A total of 244 patients (men: women = 166: 78; mean age, 64.4 years old) suspected of having ischemic cardiac disease and had undergone echocardiography within 3 months before and after CCTA were included in the study. Systematic errors in ejection fraction (EF) were corrected by calculating ΔEF from the EF difference between echocardiography and CCTA in patients not using β- blockers. Univariate and multivariate analyses were performed for factors affecting ΔEF. In addition, HR between, before, and during CCTA were compared by Wilcoxon's test. RESULTS: Temporary oral or intravenous administration of β-blockers at the CCTA had no significant effects on EF (p = 0.70), whereas HR was significantly decreased (p < 0.001). However, regular administration of β-blockers increases the EF on CCTA. CONCLUSION: The administration of β-blockers immediately before CCTA affects HR but not EF. Premedication with β-blockers can be safely used for patients who undergo CCTA, and CCTA is useful for EF evaluation, independent of the use of β-blockers.