Role of Cardiac Computed Tomography for Etiology Evaluation of Newly Diagnosed Heart Failure with Reduced Ejection Fraction

Abstract

Delayed-enhanced dual-energy computed tomography (DECT) can evaluate the extent and degree of myocardial fibrosis while coronary CT angiography (CCTA) is a widely accepted coronary artery evaluation method. We sought to describe the role of combined cardiac CT for the evaluation of underlying etiology in patients with newly diagnosed heart failure with reduced ejection fraction (HFrEF). Sixty-three consecutive patients (31 men, 63 ± 16 years) with newly diagnosed HFrEF were enrolled in this prospective study. Coronary artery disease and myocardial fibrosis were evaluated on CCTA and DECT, respectively, and the tentative underlying etiologies of heart failure (HF) were determined with combinations of findings from both CTs. Concordance between tentative etiologies from cardiac CT and final etiologies from clinical decisions within a 2-year follow-up was assessed. Eighteen patients were diagnosed with ischemic HF on initial cardiac CT, and the final diagnosis was not changed. Another 45 patients with nonischemic HF included tentative etiologies of dilated cardiomyopathy (n = 32, 71.1%), sarcoidosis or myocarditis (n = 8, 17.8%), amyloidosis (n = 2, 4.4%), noncompaction (n = 2, 4.4%) and arrhythmogenic right ventricular cardiomyopathy (n = 1, 2.2%). Five nonischemic HF patients showed different etiologies between initial cardiac CT and clinical decisions. The concordance between cardiac CT and clinical decisions was 92.1%. A high degree of concordance was achieved between tentative etiologies from cardiac CT and final diagnoses from clinical decisions. Combined cardiac CT is a feasible, safe and effective imaging tool for the initial evaluation of newly diagnosed HFrEF patients.

Keywords: coronary computed tomographic angiography; delayed-enhanced cardiac computed tomography; etiology; heart failure with reduced ejection fraction.

Figure 1

Flow diagram for cardiac CT scanning. CCTA = coronary computed tomographic angiography; DECT = dual-energy computed tomography.

Figure 2

Tentative etiologies of heart failure from cardiac CT findings. Numbers in parentheses mean the number of patients for each category. Red color means the presence of significant coronary artery disease in accordance with ischemic heart failure criteria. ARVC = arrhythmogenic right ventricular cardiomyopathy, LV = left ventricular, EP = epicardial pattern, MDE = myocardial delayed enhancement, MW = midwall pattern, PA = patchy pattern, SE = subendocardial pattern, TR = transmural pattern.

Figure 3

Representative cases of nonischemic heart failure. No MDE is noted on the LV (Group I) (A). Ill-defined midwall MDE (arrow heads) is presented in the mid LV septum (Group III) (B). Multifocal epicardial MDEs (arrows) are noted in the basal septum (Group IV) (C). Global subendocardial MDE (open arrows) is demonstrated along the LV (Group V) (D). LV = left ventricle, MDE = myocardial delayed enhancement.

Figure 4

Representative case of ischemic heart failure. On coronary CT angiography (A), total occlusion of the proximal left anterior descending artery (white arrow) is noted, and this finding was confirmed on conventional coronary angiography (black arrow) (B). On delayed-enhanced dual-energy CT with the four-chamber plane (C), subendocardial delayed enhancement is noted on the apical left ventricle and septal wall of the mid left ventricle (white open arrows), which was confirmed on cardiac MR (black open arrows) (D).

Figure 5

Differences between tentative etiologies from cardiac CT and final etiologies from clinical decisions. Numbers in parentheses mean the number of patients for each category. ARVC = arrhythmogenic right ventricular cardiomyopathy, LV = left ventricular.