Identifying left ventricular dysfunction using prospective electrocardiogram-triggered coronary computed tomography angiography

Abstract

PurposeCoronary computed tomography angiography (CCTA) is an important non-invasive tool for the assessment of coronary artery disease and the delivery of information incremental to coronary anatomy. CCTA measured left ventricular (LV) mid-diastolic volume (LVMDV) and LV mass (LVMass) have important prognostic information but the utility of prospectively ECG-triggered CCTA to predict reduced left ventricular ejection fraction (LVEF) is unknown. The objective of this study was to determine if indexed LVMDV (LVMDVi) and the LVMDV:LVMass ratio on CCTA can identify patients with reduced LVEF. Materials/methods8179 patients with prospectively ECG-triggered CCTA between November 2014 and December 2019 were reviewed. A subset derivation cohort of 4352 healthy patients was used to define normal LVMDVi and LVMDV:LVMass. Sex-specific thresholds were tested in a validation cohort of 1783 patients, excluded from the derivation cohort, with cardiac disease and known LVEF. The operating characteristics for 1 SD above the mean were tested for the identification of abnormal LVEF, LVEF≤35 ​% and ≤30 ​%. ResultsThe derivation cohort had a mean LVMDVi of 61.0 ​± ​13.7 ​mL/m2 and LVMDV:LVMass of 1.11 ​± ​0.24 ​mL/g. LVMDVi and LVMDV:LVMass were both higher in patients with reduced LVEF than those with normal LVEF (98.8 ​± ​40.8 ​mL/m2 vs. 63.3 ​± ​19.7 ​mL/m2, p ​< ​0.001, and 1.32 ​± ​0.44 ​mL/g vs. 1.05 ​± ​0.28 ​mL/g, p ​< ​0.001). Both mean LVMDVi and LVMDV:LVMass increased with the severity of LVEF reduction. Sex-specific LVMDVi thresholds were 79 ​% and 80 ​% specific for identifying abnormal LVEF in females (LVMDVi ​≥ ​69.9 ​mL/m2) and males (LVMDVi ​≥ ​78.8 ​mL/m2), respectively. LVMDV:LVMass thresholds had high specificity (87 ​%) in both females (LVMDVi:LVMass ​≥ ​1.39 ​mL/g) and males (LVMDVi:LVMass ​≥ ​1.30 ​mL/g). ConclusionOur study provides reference thresholds for LVMDVi and LVMDV:LVMass on prospectively ECG-triggered CCTA, which may identify patients who require further LV function assessment.