Assessment of Diffuse Ventricular Fibrosis in Atrial Fibrillation Using Cardiac CT-Derived Myocardial Extracellular Volume Fraction

Introduction: Previous cardiac MRI studies reported that the baseline diffuse LV fibrosis status should be evaluated before performing catheter ablation (CA) to identify the responders early and triage them with appropriate treatment. However, no study has been conducted to evaluate diffuse LV fibrosis in conjunction with pre-ablation planning cardiac CT. Objectives: The purpose of this study was to quantify diffuse left ventricular (LV) fibrosis by the CT-derived extracellular volume fraction (CT-ECV%) in conjunction with cardiac CT performed for CA planning and evaluate its determinants in patients with atrial fibrillation (AF). Methods: Prior to AF ablation, 98 patients (50 patients with paroxysmal AF and 48 patients with persistent AF) underwent pre-ablation planning cardiac CT. Additionally, delayed cardiac CT was performed to measure CT-ECV% as an index of diffuse myocardial fibrosis. Results: Persistent AF patients more frequently had a history of heart failure. Left atrial (LA) volume index was greater in persistent AF patients compared with paroxysmal AF patients. CT-ECV% of persistent AF patients was significantly higher than that of paroxysmal AF patients (30 ± 5 % vs. 26 ± 5 %, p < 0.001). Univariate and multivariate analysis revealed that only persistent AF was independent associated with CT-ECV%. Furthermore, CT-ECV% in recurrence group after CA for AF was higher than that in non-recurrence group (29 ± 4 % vs. 26 ± 5 %, p = 0.013). Multivariate logistic regression analysis revealed that CT-ECV% was significantly correlated with AF recurrence after CA for AF. Receiver operating characteristic analysis showed that more than 28 % in the CT-ECV% was a significant predictor of AF recurrence (area under the curve 0.692, log-rank test: p < 0.001). Conclusions: The quantification of diffuse LV fibrosis by CT-ECV% in conjunction with pre-ablation planning cardiac CT is feasible in AF patients, and persistent AF is independently associated with increasing diffuse LV fibrosis. Furthermore, CT-ECV% was significantly associated with AF recurrence after CA for AF. These findings suggested that it was more important to evaluate cardiac remodeling using CT and intervene early in AF.

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Left ventricular fibrosis by extracellular volume fraction and the risk of atrial fibrillation recurrence after catheter ablation

Cardiovascular Diagnosis and Therapy ◽

10.21037/cdt.2019.12.03 ◽

2019 ◽

Vol 9 (6) ◽

pp. 578-585

Author(s):

Songnan Li ◽

Lei Zhao ◽

Xiaohai Ma ◽

Rong Bai ◽

Jie Tian ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Volume Fraction ◽

Extracellular Volume ◽

Extracellular Volume Fraction ◽

Left Ventricular ◽

Atrial Fibrillation Recurrence ◽

Ventricular Fibrosis

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A Framework of Whole Heart Extracellular Volume Fraction Estimation for Low-Dose Cardiac CT Images

IEEE Transactions on Information Technology in Biomedicine ◽

10.1109/titb.2012.2204405 ◽

2012 ◽

Vol 16 (5) ◽

pp. 842-851 ◽

Cited By ~ 10

Author(s):

Xinjian Chen ◽

Marcelo S. Nacif ◽

Songtao Liu ◽

Christopher Sibley ◽

Ronald M. Summers ◽

...

Keyword(s):

Low Dose ◽

Cardiac Ct ◽

Volume Fraction ◽

Extracellular Volume ◽

Extracellular Volume Fraction ◽

Ct Images ◽

Whole Heart

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Extracellular volume fraction by T1 mapping predicts omprovement of left ventricular ejection fraction after catheter ablation in patients with non-ischemic cardiomyopathy and atrial fibrillation

European Heart Journal ◽

10.1093/ehjci/ehaa946.0261 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

M Azuma ◽

S Kato ◽

S Kodama ◽

K Hayakawa ◽

M Kagimoto ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Myocardial Fibrosis ◽

T1 Mapping ◽

Volume Fraction ◽

Extracellular Volume ◽

Extracellular Volume Fraction ◽

Left Ventricular ◽

Left Ventricular Ejection ◽

Risk Of Death

Abstract Background The Catheter Ablation versus Standard Conventional Therapy in Patients with Left Ventricular Dysfunction and Atrial Fibrillation (CASTLE-AF) trial has shown that the catheter ablation (CA) for atrial fibrillation (AF) significantly reduced the risk of death and hospitalization for heart failure in patients with non-ischemic dilated cardiomyopathy (NIDCM) and AF (N Engl J Med 2018; 378:417–27). In addition, the Catheter Ablation Versus Medical Rate Control in Atrial Fibrillation and Systolic Dysfunction (CAMERA-MRI) study demonstrated that the absence of myocardial fibrosis on late gadolinium enhanced (LGE) magnetic resonance imaging (MRI) is associated with improvement of left ventricular systolic function after CA in NIDCM patients with AF (J Am Coll Cardiol 2017; 70:1949–61). Extracellular volume fraction (ECV) by T1 mapping has emerges as a non-invasive mean to quantify diffuse myocardial fibrosis. Purpose The aim of this study was to compare the predictive value of LGE-MRI and ECV by T1 mapping for the prediction of improvement of LVEF after CA in NIDCM patients. Methods A total of twenty-eight patients with NIDCM and AF (age: 67±10 years; 25 (89%) male; LVEF: 34.1±8.8%) were studied. Using a 1.5T MR scanner and 32 channel cardiac coils, cine MRI, LGE-MRI, pre- and post- T1 mapping images of LV wall at mid-ventricular level (modified Look-Locker inversion recovery sequence) were acquired. Myocardial fibrosis on LGE was defined as area with >5SD signal intensity of normal myocardium. ECV from six segments of mid ventricular level were averaged for each patient. All patients underwent CA for AF, and the improvement of LVEF before and after CA were evaluated by echocardiography. Results All patients restored sinus rhythm after CA at the time of echocardiography. The mean LVEF was 34.1±8.8% before CA and 49.1±12.0% after CA (p<0.001), resulting an improvement of 15.0±11.8%. Significant correlation was found between improvements in LVEF and amount of fibrosis on LGE-MRI (r=−0.40, p=0.034), improvement of LVEF and ECV (r=−0.55, p=0.008). In the ROC analysis, ECV had a higher discriminative ability for the improvement of LVEF after CA compared with amount of fibrosis on LGE-MRI (AUC 0.885 vs 0.650) (Figure). Conclusions In NIDCM patients with AF, ECV by T1 mapping had better predictive ability for improvement of LVEF after CA in comparison to LGE-MRI. ROC curves of ECV and LGE-MRI Funding Acknowledgement Type of funding source: None

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