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Background: Left atrial (LA) fibrosis is thought to be a substrate for atrial fibrillation (AF) and can be quantified by late gadolinium enhancement magnetic resonance imaging (LGE‐MRI). Fibrosis formation in LA is a dynamic process and may either progress or regress following AF ablation. We examined the impact of postablation progression in LA fibrosis on AF recurrence. Methods: LA enhancement in LGE‐MRI was quantified in 127 consecutive patients who underwent first time AF ablation. Serial LGE‐MRIs were done prior to AF ablation, 3 months postablation and at least 12 months after second LGE‐MRI. Transient postablation lesion (TL) was defined as atrial enhancement caused by ablation lesions that was detected on the first (3 month) but not on the second postablation LGE‐MRI. New fibrosis (NF) was defined as atrial enhancement detected on the most recent LGE‐MRI, at least 15 months after the ablation procedure. AF recurrence and its correlation with TL and NF was assessed in all patients during the follow‐up period. Results: An increase of 1% NF increased the chance of postablation AF recurrence by 3% (hazard ratio [HR] 1.03, 95% CI 1‐1.06, P =.05). TL had no significant impact on recurrence (P =.057). After adjusting for cardiovascular risk factors, HR increased as NF became greater. Greater volume of NF (≥21%) corresponded with lower arrhythmia‐free survival (37% vs 62%, P =.01). Conclusion: NF formation postablation of AF is a novel marker of long‐term procedural outcome. Extensive NF is associated with significantly higher risk of atrial arrhythmia recurrence. [ABSTRACT FROM AUTHOR]

Introduction: Besides the traditional concept of atrial fibrillation (AF) perpetuating atrial structural remodeling, there is increasing evidence that atrial fibrosis might precede AF, highlighting the need for better characterization of the fibrotic substrate. We aimed to assess atrial fibrosis by use of late gadolinium enhancement magnetic resonance imaging (LGE‐MRI) in non‐AF individuals and to identify predisposing risk factors. A second aim was to establish a risk score for the prevalence of AF using atrial fibrosis in addition to established clinical variables. Methods and Results: Non‐AF individuals without structural heart disease (n = 91) and matched AF controls (n = 91) underwent MRI for assessment of LGE. According to the established UTAH classification, atrial LGE ≥20% was considered extensive. Mean left atrial (LA) fibrosis in non‐AF and AF individuals were 8.8 ± 6.5% and 12.5 ± 5.8%, respectively. Body mass index (BMI) >30 kg/m 2 and LA volume were predictors of atrial fibrosis. Diastolic function was not significantly different with respect to atrial fibrosis. A novel scoring system for the prevalence of AF (2 points for arterial hypertension and/or left ventricular ejection fraction <55%; 3 points for atrial fibrosis >6%) was derived demonstrating that patients in the intermediate/high‐risk group had a significantly increased risk of AF. Conclusion: This study reports unexpectedly high atrial fibrosis in non‐AF patients without apparent heart disease, highlighting the concept that structural fibrotic alterations may precede AF onset in a significant proportion of individuals. BMI as a predictor of atrial fibrosis suggests that lifestyle and drug intervention, that is, weight reduction, could positively influence fibrosis development. The derived risk score for AF prevalence provides the basis for prospective studies on AF incidence. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the risk of heart disease related death (HDRD) following radiation therapy (RT) for esophageal cancer (EC)., Methods: Using the Surveillance, Epidemiology, and End Results (SEER) database, two cohorts of patients with EC were created: (I) patients who received RT with their initial therapy; and (II) those who did not. Heart disease specific survival (HDSS) was analyzed using Kaplan-Meier methods. Cox proportional-hazards regression methods were used for univariate and multivariate analyses., Results: We identified 40,778 patients with EC. A total of 26,377 patients received RT and 14,401 did not. HDSS analysis revealed increased risk of HDRD in those receiving RT (P<0.05), with an absolute risk of HDRD of 2.8%, 5.3% and 9.4% at 5-, 10- and 20-year, respectively. Log rank test of HDSS revealed the risk of HDRD became significant at 8 months (P<0.05). The following were associated with HDRD: RT, age, race, stage at presentation, time period of diagnosis, and known comorbid condition keeping one from esophagectomy. On multivariate analysis, RT remained predictive of HDRD [hazard ratio (HR) 1.46, P<0.05]. When considering only candidates for definitive therapy, RT remained predictive of HDRD on univariate (HR 1.53, P<0.0001) and multivariate (HR 1.62, P<0.0001) analyses., Conclusions: The use of RT leads to increased risk of HDRD that is detectable as early as eight months from diagnosis. More research is needed to define optimal dose volume parameters to prevent cardiac death. Consideration should be given to this risk in relation to prognosis and the expected benefits of RT.

Aim: Late gadolinium enhanced (LGE) magnetic resonance imaging (MRI) is a useful tool for facilitating ventricular tachycardia (VT) ablation. Unfortunately, most VT ablation candidates often have prophylactic implantable cardioverter-defibrillator (ICD) and do not undergo cardiac MRI largely due to image artefacts generated by ICD. A prior study has reported success of 'wideband' LGE MRI for imaging myocardial scar without image artefacts induced by ICD at 1.5T. The purpose of this study was to widen the availability of wideband LGE MRI to 3T, since it has the potential to achieve higher spatial resolution than 1.5T., Methods and Results: We compared the performance of standard and wideband LGE MRI pulse sequences in phantoms and canines with myocardial lesions created by radiofrequency ablation. Standard LGE MRI produced image artefacts induced by ICD and 49% accuracy in detecting 97 myocardial scars examined in this study, whereas wideband LGE MRI produced artefact-free images and 94% accuracy in detecting scars. The mean image quality score (1 = nondiagnostic, 2 = poor, 3 = adequate, 4 = good, 5 = excellent) was significantly (P < 0.001) higher for wideband (3.7 ± 0.8) than for standard LGE MRI (2.1 ± 0.7). The mean artefact level score (1 = minimal, 2 = mild, 3 = moderate, 4 = severe, 5 = nondiagnostic) was significantly (P < 0.001) lower for wideband (2.1 ± 0.8) than for standard LGE MRI (4.0 ± 0.6). Wideband LGE MRI agreed better with gross pathology than standard LGE MRI., Conclusion: This study demonstrates the feasibility of wideband LGE MRI for suppression of image artefacts induced by ICD at 3T., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.)