Chronicity Of Atrial Fibrillation Research Articles

Abstract 14467: Left Atrial Functional Index is a Predictor of Persistent/permanent Non-valvular Atrial Fibrillation

Introduction: Chronicity of atrial fibrillation (AF) has been associated with poor cardiovascular outcomes. Left atrial function index (LAFI) is a rhythm-independent measure of LA reservoir function adjusted for LA size and stroke volume and is an established marker of risk for cardiac disease states. We sought to evaluate the role of LA function by LAFI in predicting persistent/permanent AF. Hypothesis: LAFI is a predictor of chronicity of AF. Methods: Patients attending our institution between Jan 2013 and Dec 2017 were assessed. Patients with history of non-valvular AF who received transthoracic echocardiogram (TTE) evaluation were included. In these patients, we evaluated demographic profiles, AF history, clinical comorbidities and echocardiographic data. We excluded patients with valvular AF, poor quality TTE images and incomplete clinical data. Results: Of the 665 patients (67.78±13.62years, 52% male) included, 27.8% had persistent/permanent AF. Persistent/permanent AF was associated with older age (p<0.01), heart failure (p<0.01), diabetes mellitus (p=0.02), ischaemic heart disease (p=0.02), obstructive sleep apnoea (p=0.04), renal impairment (p<0.01), lower left ventricular ejection fraction (p<0.01), higher E/e’ (p<0.01), larger LA volume index (p<0.01) and lower LAFI (p<0.01). Multi-variable analysis revealed both heart failure (OR 3.024, 95%CI 1.737 to 5.265, p<0.01) and LAFI (OR 4.881, 95%CI 2.503 to 9.519, p<0.01) as independent predictors of persistent/permanent AF. Receiver operating characteristic curve showed LAFI (see Figure; AUC 0.75, 95%CI 0.703 to 0.793, p<0.01) of less than 16.5 to have a 70% sensitivity and 70% specificity in detecting persistent/permanent AF. Conclusions: LAFI, an echocardiographic measure of atrial mechanical function, may be a useful tool in risk stratification for patients with non-valvular AF.

365 Left Atrial Functional Index is a Predictor of Persistent/permanent Non-Valvular Atrial Fibrillation

Chronicity of atrial fibrillation (AF) has been associated with poor cardiovascular outcomes. Left atrial function index (LAFI) is a rhythm-independent measure of LA reservoir function adjusted for LA size and stroke volume and is an established marker of risk for cardiac disease states. We sought to evaluate the role of LA function by LAFI in predicting persistent/permanent AF. Patients attending our institution between Jan 2013 and Dec 2017 were assessed. Patients with history of non-valvular AF who received transthoracic echocardiogram (TTE) evaluation were included. In these patients, we evaluated demographic profiles, AF history, clinical comorbidities and echocardiographic data. We excluded patients with valvular AF, poor quality TTE images and incomplete clinical data. Of the 665 patients (67.78±13.62years, 52% male) included, 27.8% had persistent/permanent AF. Persistent/permanent AF was associated with older age (p<0.01), heart failure (p<0.01), diabetes mellitus (p=0.02), ischaemic heart disease (p=0.02), obstructive sleep apnoea (p=0.04), renal impairment (p<0.01), lower left ventricular ejection fraction (p<0.01), higher E/e’ (p<0.01), larger LA volume index (p<0.01) and lower LAFI (p<0.01). Multi-variable analysis revealed both heart failure (OR 3.024, 95% CI 1.737 to 5.265, p<0.01) and LAFI (OR 4.881, 95% CI 2.503 to 9.519, p<0.01) as independent predictors of persistent/permanent AF. Receiver operating characteristic curve showed LAFI (Figure1; AUC 0.75, 95% CI 0.703 to 0.793, p<0.01) of less than 16.5 to have a 70% sensitivity and 70% specificity in detecting persistent/permanent AF LAFI, an echocardiographic measure of atrial mechanical function, may be a useful tool in risk stratification for patients with non-valvular AF.

Left Atrial Fibrosis Assessed with Cardiac MRI in Patients with Paroxysmal and Those with Persistent Atrial Fibrillation.

Background Electrophysiology studies have demonstrated that left atrial late gadolinium enhancement (LGE) is associated with the chronicity of atrial fibrillation (AF). To date, cardiac MRI has been used to assess the extent of atrial LGE but not the distribution pattern of LGE in the left atrium. Purpose To determine whether the MRI pattern of left atrial fibrosis is associated with the chronicity of AF. Materials and Methods This retrospective study included patients with AF who underwent LGE MRI between June 2017 and May 2018. The presence of left atrial LGE was assessed at nine left atrial segments; the extent was determined by the number of segments involved. According to the chronicity of AF, patients were separated into paroxysmal AF (PAF) and persistent AF (PeAF) groups. The location and extent of left atrial LGE were compared between PAF and PeAF by using the χ2 test and logistic regression analysis. Results Of the 195 patients (mean age, 55 years ± 10 [standard deviation], 161 men), 74 (38%) had PAF and 121 (62%) had PeAF. Of all patients, 114 (58.4%) had at least one left atrial LGE segment. The mean number of LGE segments was higher (1.4 ± 1.1 vs 0.6 ± 0.7, P = .002) in the PeAF group than in the PAF group. The incidence of LGE at the left inferior pulmonary vein (LIPV) antrum was higher in the PeAF group than in the PAF group (39.2% [29 of 74] vs 7.4% [nine of 121]; P < .001). In multivariable analysis, LGE at the LIPV antrum was independently associated with PeAF (odds ratio = 4.2; 95% confidence interval: 1.7, 10.5; P < .001). Conclusion The presence of fibrosis assessed with late gadolinium enhancement MRI of the left inferior pulmonary vein antrum was associated with persistent atrial fibrillation. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Almeida in this issue.

Epicardial Fat Thickness and Free Fatty Acid Level are Predictors of Acute Ischemic Stroke with Atrial Fibrillation.

BACKGROUNDIncreased epicardial fat is known to be associated with the presence and chronicity of atrial fibrillation (AF). Free fatty acids (FFAs) are major components of epicardial fat; however, their potential association with AF in ischemic stroke has not been investigated. We aimed to assess the performance of echocardiographic epicardial fat thickness (EFT) and plasma FFA level in identifying patients with ischemic stroke and AF.METHODSWe enrolled a total of 214 consecutive patients (mean age, 66.8 ± 12.3 years; 39.7% women) diagnosed with acute ischemic stroke between March 2011 and June 2014. The patients were divided into two groups: ischemic stroke with AF (n = 35, 16.4%) and ischemic stroke without AF (n = 179, 83.6%).RESULTSThe ischemic stroke with AF group showed significantly higher serum FFA level (1379.7 ± 717.5 vs. 757.8 ± 520.5 uEq/L, p < 0.0001) and EFT (6.5 ± 1.2 vs. 5.3 ± 1.2 mm, p < 0.001) than the group without AF. Multivariable logistic regression analysis demonstrated that age (odds ratio [OR], 1.112), serum FFA level (OR, 1.002), and EFT (OR, 1.740) were independently associated with the ischemic stroke group with AF. EFT and FFA significantly improved the goodness-of-fit and discriminability of the simple regression model including age as a covariate (log likelihood difference, 21.35; p < 0.001; c-index difference, 17.9%; p < 0.001).CONCLUSIONSHigh EFT and serum FFA level were associated with ischemic stroke in patients with AF. Echocardiographic EFT and serum FFA level can play a significant role in identifying ischemic stroke with AF.

Increased epicardial fat is independently associated with the presence and chronicity of atrial fibrillation and radiofrequency ablation outcome.

To determine whether intrathoracic fat volumes are associated with presence and chronicity of atrial fibrillation (AF) and radiofrequency ablation (RFA) treatment outcome. IRB approval was obtained and patient consent was waived for this HIPAA-compliant retrospective study. 169 patients with AF (75 non-paroxysmal and 94 paroxysmal) and 62 control patients underwent cardiac CT examination. Extrapericardial (EPFV) and epicardial fat volumes (EFV) were measured on CT, the sum of which is the total intrathoracic fat volume. Associations between these three fat volumes and presence and chronicity of AF, and outcome after RFA, were evaluated using logistic regression analysis. EFV was significantly associated with presence [OR 1.01 (95% CI 1.003-1.03), p = 0.01], chronicity of AF [1.008 (1.001-1.020), p = 0.03] and AF recurrence after RFA [1.009 (1.001-1.01), p = 0.02] after adjustment for age, gender and BMI. Patients with a larger EFV had a shorter time to AF recurrence (p = 0.017) and a higher rate of recurrence (54% vs 46%) (p = 0.002) after RFA. EPFV had no significant associations. Increased epicardial fat is associated with the presence and chronicity of AF, a higher probability of AF recurrence after RFA and a shorter AF-free interval. • Increased epicardial fat is associated with presence and chronicity of atrial fibrillation • Extensive epicardial fat is associated with earlier recurrences of AF after ablation • Extensive epicardial fat may reduce transmurality of ablation by affecting current dynamics.

Left Atrial Function and Maximum Volume as Determined by MDCT Are Independently Associated with Atrial Fibrillation

To assess whether left atrial (LA) volume, function, and diameter as determined by multidetector computed tomography (MDCT) are associated with the presence and chronicity of atrial fibrillation (AF). A total of 232 subjects, 156 with AF (43 with chronic and 113 with paroxysmal) and 76 normal subjects, formed the study population. AF subjects underwent MDCT of the pulmonary veins and LA, and normal subjects underwent coronary computed tomography (CT), on which LA volume, function, and diameter were measured. Associations between each MDCT LA parameter and presence and chronicity of AF were assessed using logistic regression analysis. The indexed LA maximum volume (odds ratio [OR]=2.42; 95% confidence interval [CI], 1.43-4.08; P=.0009) was significantly associated with chronicity and presence of AF (OR=1.06; 95% CI, 1.03-1.10; P=.0003) after adjustment for traditional risk factors. The LA function was associated with presence of AF (OR=0.93; 95% CI, 0.89-0.97; P=.0005), but not with AF chronicity (OR=1.12; 95% CI, 0.93-1.33; P=.21). Decreased LA function is associated with presence of AF, and increased LA maximum volume is associated with presence and chronicity of AF, independent of traditional risk factors.

Effect of Transvenous Electrical Cardioversion on Plasma Cardiac Troponin I Concentrations in Horses with Atrial Fibrillation

Whether electrical cardioversion of cardiac arrhythmias results in cardiomyocyte damage is unknown. To describe effect of transvenous electrical cardioversion (TVEC) on plasma cardiac troponin I (cTnI) concentration in horses. All horses presented to the Cornell University Hospital for Animals for cardioversion of atrial fibrillation between May 2006 and October 2008 were eligible for inclusion in the study. Owners of 14 horses elected for TVEC and each horse was then enrolled (16 procedures). Prospective observational study measuring concentrations of plasma cTnI before and after TVEC. Median cTnI concentration increased from 0.045 ng/mL at baseline (range 0.0-0.20 ng/mL) to 0.11 ng/mL after TVEC (range 0.0-3.73 ng/mL) (P= .036). This increase was not associated with the number of shocks delivered, maximal energy delivered, cumulative energy delivered, chronicity of atrial fibrillation before cardioversion, or positioning of the pulmonary artery catheter. The increase in cTnI is unlikely to be clinically important. The increase might be correlated with persistent atrial dysfunction after TVEC, suggesting that a longer convalescent period after the procedure could be warranted.