Device-detected Atrial Fibrillation Research Articles

Abstract 21319: Racial Differences in the Prevalence of Atrial Fibrillation in Patients With Dual-Chamber Pacemakers

Introduction: Several cohort studies have reported racial differences in prevalence of atrial fibrillation (AF). This may be due to ascertainment bias. Thus, we aimed to determine incidence of AF with respect to race in patients with sinus node dysfunction and conduction disease. Hypothesis: Ethnicity may have significant impact on development of AF in patients with sinus node dysfunction and conduction disease requiring pacemaker. Methods: All patients followed at the University of Chicago with a dual-chamber pacemaker implanted between January 2005 to December 2011 and sinus node dysfunction (SND) or high-degree atrio-ventricular block (HGAVB) requiring dual chamber pacemaker were included. Patients were identified retrospectively. Electronic medical records, ECGs, device interrogation data, and procedure notes were examined. Logistic regression analysis was used to evaluate the association of race and device-detected AF incidence, controlling for clinical characteristics and medical comorbidities, including age, gender, HTN, diabetes, chronic obstructive pulmonary disease, obstructive sleep apnea, coronary artery disease (CAD), chronic kidney disease (CKD), and valvular heart disease. Results: Three-hundred and twenty-four patients met criteria, including 125 (38%) Caucasians, 173 (53%) African Americans, 7 (2.2%) Hispanics, and 10 (3.1%) Asian-Americans. Average age was 68.9 +/- 14.8, 185 (57%) were female. Chi-squared analysis revealed no significant relationship between race and diabetes, CAD, or valvular disease in this population. Hypertension (p<0.01) and CKD (p=0.02) were associated with race; both were more common in African Americans and Hispanics. In a multivariate analysis, younger age (p=0.01; OR=1.02 (1.005-1.04)), African American race (p=0.03; OR=0.6 (0.3-0.9)), and Asian American race (p=0.04; OR=0.2 (0.03-0.8)) were associated with a decreased risk of device-detected AF. Conclusions: African American race was associated with a decreased incidence of AF in patients with continuous monitoring, despite a relatively increased rate of CKD and hypertension in this population. This suggests that racial differences in AF cannot be fully explained by ascertainment bias.

Detection of new atrial fibrillation in patients with cardiac implanted electronic devices and factors associated with transition to higher device-detected atrial fibrillation burden

In patients with cardiac implanted electronic devices, detection of new atrial fibrillation (AF) is associated with an increased risk of stroke. To characterize daily AF burden at first detection and the rate of temporal transition to higher device-detected AF burden. A pooled analysis of data from 3 prospective projects was analyzed, and 6580 patients (mean age 68 ± 12 years, 72% male) with no history of AF and no use of anticoagulants at baseline were identified. Various thresholds of daily AF burden (5 minutes and 1, 6, 12, and 23 hours) were analyzed. Among the study population of 6580 patients, a new AF, with an AF burden of ≥5 minutes, was detected in 2244 patients (34%) during a follow-up period of 2.4 ± 1.7 years. Among these patients, 1091 (49.8%) transitioned to a higher AF-burden threshold during follow-up. A higher duration of daily AF burden manifest at first detection and CHADS2 score ≥2 were associated with faster transition to a subsequent higher burden. Approximately 24% of patients transitioned from a lower threshold to a daily AF burden of ≥23 hours during follow-up. More than one-third of patients with no history of AF developed device-detected AF, with attainment of different thresholds of daily AF burden over time. Continuous long-term monitoring, especially when the initial detection corresponds to a higher daily AF burden and the CHADS2 score is ≥2, could support timely clinical decisions on anticoagulation by capturing transitions to higher AF-burden thresholds.

Atrial high-rate episodes predict clinical outcome in patients with cardiac resynchronization therapy

Objectives. Up to 50% of patients qualified for cardiac resynchronization therapy (CRT) have documented atrial fibrillation (AF) prior to CRT-implantation. This finding is associated with worse prognosis but few studies have evaluated the importance of post-implant device-detected AF. This study aimed to assess the prognostic impact of device-detected atrial high-rate episodes (AHRE), as a surrogate for AF. Design. Data were retrospectively obtained from consecutive patients receiving CRT. Baseline clinical data and data from CRT device-interrogations, performed at a median of 12.2 months after CRT-implantation, were evaluated with regard to prediction of the composite endpoint of death, heart transplant or appropriate shock therapy. Median follow-up time was 51 months post-implant. Results. The study included 377 patients. Preoperative AF was present in 49% and associated with worse outcome. The cumulative burden of AHRE at 12 months post-implant was an independent predictor of the primary endpoint. During the first 12 months after CRT-implantation, AHRE were detected in 25% of the patients with no preoperative diagnosis of AF. This finding was not associated with worse outcome. Conclusions. In CRT recipients, the cumulative burden of AHRE during the first year of follow-up was associated with worse long-term clinical outcome. Prospective trials are needed to determine if a rhythm control strategy is to be preferred in patients with CRT.

Incidence of Device-Detected Atrial Fibrillation and Long-Term Outcomes in Patients With Hypertrophic Cardiomyopathy

Atrial fibrillation (AF) is a common complication of hypertrophic cardiomyopathy (HC) and associated with adverse clinical outcomes, such as thromboembolisms. Cardiac implantable electronic devices (CIEDs) enable early detection of AF. The aim of this study was to assess the incidence of device-detected AF and the impact on long-term outcomes in patients with HC. The cohort consisted of 132 patients (63% men, mean age 52 ± 16years) with a diagnosis of HC and a CIED. Follow-up started at the date of CIED implantation to assess the incidence of device-detected AF. Patients with persistent AF at the time of implantation were excluded from the analysis of the incidence of AF. End points were all-cause and cardiac mortality, device-detected AF, and thromboembolism (stroke, transient ischemic attack, or peripheral arterial embolism). In total, 114 patients were in sinus rhythm at time of CIED implantation. During the median 2.8 (interquartile range 1.2 to 5.4) years of follow-up, device-detected AF occurred in 29 patients (25%), resulting in an annual incidence of 7.0%/year. Device-detected AF led to a change in the clinical management in 22 patients (76%). Anticoagulation therapy was started in 13 (45%), antiarrhythmic medication in 9 (31%), and electrical cardioversion in 8 (28%) patients. Six patients (5%) suffered a thromboembolic complication. All-cause mortality was 27 (20%), and cardiac mortality was 21 (16%). A history of AF at time of implantation was an independent predictor of cardiac death (hazard ratio 4.7, p= 0.003). In conclusion, the incidence of device-detected AF in patients with HC was 7.0%/year, leading to a change in clinical management in the majority (76%) of cases to reduce the risk of thromboembolic complications. These findings stress the importance of AF detection in HC and advocate vigilant interrogation of the device.

Abstract 14997: Subclinical Device-Detected Atrial Fibrillation is Associated With a Higher Risk of Adverse Cardiovascular Outcomes to the Same Extent as Clinical Atrial Fibrillation

Introduction: Atrial fibrillation (AF) is a known risk factor for adverse cardiovascular (CV) outcomes in patients with implantable cardioverter-defibrillators (ICDs). As the use of ICDs becomes more common, subclinical device-detected atrial fibrillation (SAF) is increasingly being identified. Studies have shown an association between SAF and increased risk of thromboembolic events. However, no study has compared the risk of adverse CV outcomes of SAF vs. clinical AF (CAF). Hypothesis: In patients with ICDs, SAF is associated with adverse CV outcomes to the same extent as CAF. Methods: We identified patients who had ICD implantation at the University of Minnesota Medical Center between Jan 1, 2003 and Dec 31, 2009. Baseline data on demographics, CV risk factors, diagnoses, and medications were collected. Follow-up was through Dec 31, 2012. Our primary outcome was a composite CV outcome (see table). CAF episodes were identified from clinical documents confirmed by ECGs. SAF episodes of any duration were identified from ICD interrogation reports. We fit a multivariable Cox proportional hazards model and used backwards stepwise selection to identify the most parsimonious model to predict the outcome (0.05 threshold). Results: We included 371 patients; 37 had incident or recurrent CAF; 88 had SAF. Median follow up was 490 days. The full model included age, sex, coronary artery disease, diabetes, ejection fraction, hypertension, and use of beta-blockers, anticoagulants, and ACE inhibitors. The table shows the most parsimonious model for prediction of the composite outcome. Conclusions: SAF and CAF were significantly associated with a greater than 11-fold and 9-fold increased risk of adverse CV outcomes, respectively. This study indicates that SAF is associated with increased risk of CV outcomes to the same extent as CAF. More research is needed to determine whether treatment of SAF (e.g., anticoagulation) will lead to improved outcomes in patients with ICDs.

Detection of occult atrial fibrillation in patients with embolic stroke of uncertain source: a work in progress.

Atrial fibrillation accounts for a substantial proportion of ischemic strokes of known etiology and may be responsible for an additional subset of the 25–40% of strokes of unknown cause (so-called cryptogenic). Oral anticoagulation is significantly more effective than antiplatelet therapy in the secondary prevention of atrial fibrillation-related strokes, providing justification for developing more sensitive approaches to detecting occult paroxysms of atrial fibrillation. In this article, we summarize the current state of knowledge regarding the value of in-hospital and out-patient monitoring for detecting atrial fibrillation in the context of cryptogenic stroke. We review the evidence for and against screening with standard Holter monitors, external loop recorders, the newer real-time continuous attended cardiac monitoring systems, cardiac implantable electronic devices, and insertable loop recorders. We review key questions regarding prolonged cardiac arrhythmia monitoring, including the relationship between duration of the atrial fibrillation episode and risk of thromboembolism, frequency of monitoring and its impact on the diagnostic yield in detecting occult or subclinical atrial fibrillation, and the temporal proximity of device-detected atrial fibrillation to stroke events. We conclude by proposing avenues for further research.

Role of atrial fibrillation burden in assessing thromboembolic risk.

Stroke represents the most devastating complication of atrial fibrillation (AF). Our understanding of the pathophysiology of thromboembolism in patients with AF remains incomplete, and as such, our assessment and management of this risk is imperfect. Current guidelines regard the risk of thromboembolism as independent of the frequency or duration of AF.1 Paradoxically, standard practice in the pericardioversion period considers thromboembolic risk to accrue after 48 hours of AF.1 This recommendation, however, is based on limited data, including an observational study of 357 patients which demonstrated that the risk of thromboembolic events was <1% in patients with AF lasting <48 hours who cardioverted without prolonged anticoagulation therapy or a transesophageal echocardiogram.2 No strong randomized control trial data exist to specifically support a 48-hour safety cut-off, and recent data suggest that the duration of AF associated with a significantly increased risk of stroke may in fact be less.3–8 The emergence of technology to allow absolute quantification of the frequency and duration, or burden, of AF offers the opportunity to refine our assessment and management of thromboembolic risk associated with AF. It has been 200 years since William Wood described a ball thrombus in the left atrium of a patient with mitral stenosis9 and 170 years since Virchow identified the critical components required for thrombus formation.10 It took until 1930 for Harvey and Levine to first declare that “auricular fibrillation definitely increases the incidence of auricular thrombosis” in an autopsy series of patients with mural thrombi.11 Uncertainty as to whether nonrheumatic AF resulted in stroke continued for the next 40 plus years until Wolfe and colleagues, in their landmark analysis using the Framingham population data, identified a 5.6-fold increased risk of stroke in patients with chronic nonvalvular AF.12 With time it would become …

The epidemic of inadequate biventricular pacing in patients with persistent or permanent atrial fibrillation and its association with mortality.

We classified patients' atrial fibrillation (AF), assessed its impact on biventricular pacing (BIVP%), and determined whether AF classification or BIVP% independently correlate with mortality in cardiac resynchronization therapy defibrillator patients. Cardiac resynchronization therapy defibrillator patients were classified as permanent (daily mean AF burden ≥23 hours), persistent (≥7 consecutive days of AF ≥23 hours/d), paroxysmal (≥1 day with AF ≥6 hours), or no/little AF (all others) using device-detected AF during the 6 months postimplant. We evaluated subsequent all-cause mortality using a multivariable Cox proportional hazard regression. Among 54 019 patients (age, 70±11 years; 73% male; follow-up, 2.3±1.2 years), 8% of patients each had permanent (N=4449), persistent (N=4237), and paroxysmal AF (N=4219). A high proportion of patients with permanent (69%) and persistent (62%) AF did not achieve high BIVP (>98%). Relative to no/little AF, patients with AF had increased mortality after adjusting for age, sex, BIVP, and shocks (permanent: hazard ratio=1.28 [1.19-1.38]; P<0.001; persistent: hazard ratio=1.51 [1.41-1.61]; P<0.001). Relative to patients with BIVP >98%, patients with reduced BIVP had increased mortality after adjusting for age, sex, AF, and shocks (90%-98%: hazard ratio=1.20 [1.15-1.26]; P<0.001; <90%: hazard ratio=1.32 [1.23-1.41]; P<0.001). High BIVP% was associated with the greatest mortality improvement in permanent AF among the AF classifications. High BIVP% was not achieved in two thirds of 8686 patients with persistent or permanent AF, and these patients had an increased risk of death. A shift toward more aggressive rate control and more pacing may be necessary in patients with AF to maximize the benefits of cardiac resynchronization therapy.

Clinical significance of atrial fibrillation detected by cardiac implantable electronic devices

The detection of atrial fibrillation (AF) by a cardiac implantable electronic device (CIED) in patients without a prior history of AF is increasing. This trend is the result of the increased number of CIEDs being implanted in a population whose multiple medical comorbidities are known to predispose to AF. Cardiac implantable electronic device-detected atrial fibrillation (CDAF) is independently associated with the development of ischemic stroke, and the annual risk may depend on both total AF burden and individual risk factors. No data evaluating the benefit of oral anticoagulation in this population are available, which makes the decision to initiate anticoagulation challenging. This review analyzes the available data on CDAF and the associated risk of ischemic stroke, and it presents a rationale for the use of long-term oral anticoagulation in this population.

Device-detected atrial fibrillation and risk for stroke: an analysis of &gt;10 000 patients from the SOS AF project (Stroke preventiOn Strategies based on Atrial Fibrillation information from implanted devices)

ObjectiveThe aim of this study was to assess the association between maximum daily atrial fibrillation (AF) burden and risk of ischaemic stroke.BackgroundCardiac implanted electronic devices (CIEDs) enhance detection of AF, providing a comprehensive measure of AF burden.Design, setting, and patientsA pooled analysis of individual patient data from five prospective studies was performed. Patients without permanent AF, previously implanted with CIEDs, were included if they had at least 3 months of follow-up. A total of 10 016 patients (median age 70 years) met these criteria. The risk of ischaemic stroke associated with pre-specified cut-off points of AF burden (5 min, 1, 6, 12, and 23 h, respectively) was assessed.ResultsDuring a median follow-up of 24 months, 43% of 10 016 patients experienced at least 1 day with at least 5 min of AF burden and for them the median time to the maximum AF burden was 6 months (inter-quartile range: 1.3–14). A Cox regression analysis adjusted for the CHADS2 score and anticoagulants at baseline demonstrated that AF burden was an independent predictor of ischaemic stroke. Among the thresholds of AF burden that we evaluated, 1 h was associated with the highest hazard ratio (HR) for ischaemic stroke, i.e. 2.11 (95% CI: 1.22–3.64, P = 0.008).ConclusionsDevice-detected AF burden is associated with an increased risk of ischaemic stroke in a relatively unselected population of CIEDs patients. This finding may add to the basis for timely and clinically appropriate decision-making on anticoagulation treatment.

Disease management: atrial fibrillation and Home Monitoring

Device-detected atrial fibrillation (AF) episodes predict poor clinical outcome regardless of symptoms. Potential benefits of remote monitoring are early arrhythmia detection and patient continuous monitoring. Several studies of device remote monitoring consistently demonstrated that AF represents the most common clinical alert and that detailed information on arrhythmia onset, duration, and burden as well as on the ventricular rate may be early available for clinical evaluation. Reaction time to AF alerts was very short in all series involving either pacemakers or defibrillators and action ability of AF alerts was very high. In the Home Guide Registry, in which 1650 patients were enrolled, AF was detected in 16.3% of patients and represented 36% of all cardiovascular events during the follow-up. Timely anticoagulation introduction in asymptomatic patients may impact on the stroke rate. According to the results of repeated Monte Carlo simulations based on a real population of 166 patients, daily monitoring may reduce the 2-year stroke risk by 9-18% with an absolute reduction of 0.2-0.6%, compared with conventional inter-visit intervals of 6-12 months. In the COMPAS trial, the incidence of hospitalizations for atrial arrhythmias and related stroke was significantly higher in the control group than in the remote monitoring group. Major questions will be addressed by the ongoing IMPACT trial in which a remote monitoring guided anticoagulation strategy based on AF detection will be compared with a physician-directed standard strategy. In patients with heart failure, AF early detection combined with other indexes may help prevent hospitalizations.

Tracking Down Atrial Fibrillation in the Stroke Unit

See related article, p 2689. Optimal treatment after stroke or transient ischemic attack (TIA) requires identification of atrial fibrillation (AF) if it is present. Standard antithrombotic therapy for patients not known to have AF consists of antiplatelet agents such as aspirin or clopidogrel.1 However, antiplatelet therapy is inferior to anticoagulant therapy for secondary stroke prevention in patients with AF.2,3 Therefore, failure to detect underlying AF as a cause of stroke or TIA results in inadequate antithrombotic therapy and an unnecessarily heightened risk of recurrent stroke. Despite the high stakes, diagnosing AF in patients with stroke or TIA can be difficult. A routine 12-lead electrocardiogram will readily identify persistent AF, but AF often takes an asymptomatic and paroxysmal form that eludes detection. In a study of patients with pacemakers or implanted defibrillators, those with new device-detected AF after stroke or TIA manifested this arrhythmia a median of 5 minutes per day, and most had no AF at all on >90% of days.4 Unfortunately, intermittent AF seems to pose the same risk of stroke as sustained AF.5 Recent data indicate that a single period of AF lasting only 6 minutes independently confers a heightened risk of stroke.6 To ensure appropriate antithrombotic therapy for secondary stroke prevention, these elusive forms of AF must be reliably ruled out. In line with …

Threshold crossing of device-based intrathoracic impedance trends identifies relatively increased mortality risk

AimsThreshold crossings of impedance trends detected by implanted devices have been associated with clinically relevant heart failure events, but long-term prognosis of such events has not been demonstrated. The aim of this study is to examine the relationship between alterations in intrathoracic impedance and mortality risk in patients with implantable devices.Methods and resultsWe reviewed remote monitoring data in the de-identified Medtronic CareLink® Discovery Link that captured intrathoracic impedance trends for >6 months. The initial 6 months of the cardiac and impedance trends were used as the observation period to create the patient groups and cross-referenced with the Social Security Death Index for mortality data. In our study cohort of 21 217 patients, 36% experienced impedance threshold crossing within the initial 6 months of monitoring (defined as the ‘early threshold crossing’ group). Patients with early threshold crossings demonstrated an increased risk of age- and gender-adjusted all-cause mortality [hazard ratio (HR) 2.15, 95% confidence interval (CI) 1.95–2.38, P< 0.0001]. Increased mortality risk remained significant when analysed in subgroups of patients without defibrillator shock (HR 2.10, 95% CI 1.90–2.34, P< 0.0001, n= 1621) or within those patients without device-detectable atrial fibrillation (AF) during the initial 6 months of monitoring (HR 2.09, 95% CI 1.86–2.34, P< 0.0001, n= 17 235). Both the number and the duration of early threshold crossings of impedance trends detectable by implanted devices were associated with increased mortality risk. Furthermore, the improvement of altered impedance trends portends more favourable prognosis.ConclusionsThreshold crossing of impedance trends detectable by implanted devices is associated with relatively increased mortality risk even after adjusted for demographic, device-detected AF, or defibrillator shocks.

Device-Detected Atrial Fibrillation: Perils and Pitfalls

Atrial fibrillation (AF) is the most common sustained arrhythmia encountered in clinical practice, and has an estimated prevalence as high as 9% in elderly people. The risk of stroke is increased 5-fold in patients with nonrheumatic AF and 17fold in patients with rheumatic AF. One of the foremost goals of managing AF is the reduction of thromboembolic strokes and systemic embolism. Implantable heart rhythm devices, such as implantable cardioverter-defibrillators (ICDs), cardiac resynchronization therapy (CRT) devices (pacemakers [CRT-P] and defibrillators [CRT-D]), and permanent pacemakers (PPMs) are increasingly being used worldwide. These devices are capable of sensing intrinsic atrial activity and often detect spontaneous atrial high rate events (AHREs) in asymptomatic patients. Barring any spurious causes, AHREs seen by these devices are supposedly tantamount to having AF or atrial flutter (AFL), because several studies have documented a correlation between AHRE and electrocardiogram (ECG)-documented episodes of AF/ AFL with a high degree of sensitivity and specificity. However, the critical duration, frequency, or overall burden of AHRE that increases stroke risk is still unknown, and thus the threshold level of AHREs that warrants anticoagulation is still unclear. This article reviews the current literature on the risk of stroke with device-detected AHREs and raises questions that need further clarification.

The Relationship Between Daily Atrial Tachyarrhythmia Burden From Implantable Device Diagnostics and Stroke Risk

Background— It is unknown if brief episodes of device-detected atrial fibrillation (AF) increase thromboembolic event (TE) risk. Methods and Results— TRENDS was a prospective, observational study enrolling patients with ≥1 stroke risk factor (heart failure, hypertension, age ≥65 years, diabetes, or prior TE) receiving pacemakers or defibrillators that monitor atrial tachycardia (AT)/AF burden (defined as the longest total AT/AF duration on any given day during the prior 30-day period). This time-varying exposure was updated daily during follow-up and related to TE risk. Annualized TE rates were determined according to AT/AF burden subsets: zero, low (&lt;5.5 hours [median duration of subsets with nonzero burden]), and high (≥5.5 hours). A multivariate Cox model provided hazard ratios including terms for stroke risk factors and time-varying AT/AF burden and antithrombotic therapy. Patients (n=2486) had at least 30 days of device data for analysis. During a mean follow-up of 1.4 years, annualized TE risk (including transient ischemic attacks) was 1.1% for zero, 1.1% for low, and 2.4% for high burden subsets of 30-day windows. Compared with zero burden, adjusted hazard ratios (95% CIs) in the low and high burden subsets were 0.98 (0.34 to 2.82, P =0.97) and 2.20 (0.96 to 5.05, P =0.06), respectively. Conclusions— The TE rate was low compared with patients with traditional AF with similar risk profiles. The data suggest that TE risk is a quantitative function of AT/AF burden. AT/AF burden ≥5.5 hours on any of 30 prior days appeared to double TE risk. Additional studies are needed to more precisely investigate the relationship between stroke risk and AT/AF burden.

Monitored Atrial Fibrillation Duration Predicts Arterial Embolic Events in Patients Suffering From Bradycardia and Atrial Fibrillation Implanted With Antitachycardia Pacemakers

The aim of our study was to evaluate arterial embolism (AE) occurrence rates and predictors in patients suffering from bradycardia and wearing a pacemaker with antitachycardia pacing therapies. Atrial fibrillation (AF) is associated with a high incidence of AE. A total of 725 patients (360 men, age 71 +/- 11 years) were implanted with a DDDRP pacemaker (Medtronic AT500, Medtronic Inc., Minneapolis, Minnesota). At baseline 225 (31.0%) patients received antiplatelet therapy and 264 (36.4%) patients received anticoagulation agents. Over a median 22-month follow-up (25th to 75th interquartile range 16 to 30 months), AE occurred in 14 (1.9%) patients: 7 patients suffered a nonfatal ischemic stroke (0.6% per year), 4 patients had transient ischemic attack (0.34% per year), and 3 patients had embolic complications. Among baseline patients' characteristics, multivariate logistic analysis showed that embolic events are independently associated to ischemic heart disease (7.0 odds ratio [OR], 95% confidence interval [CI] 2.3 to 21.3, p = 0.001), prior embolic event (7.3 OR, 95% CI 1.2 to 43.9, p = 0.029), diabetes (5.0 OR, 95% CI 1.2 to 15.7, p = 0.032), and hypertension (4.1 OR, 95% CI 1.1 to 15.6, p = 0.036). The risk of embolism, adjusted for known risk factors, was 3.1 times increased (95% CI 1.1 to 10.5, p = 0.044) in patients with device-detected atrial fibrillation episodes longer than one day during follow-up. In a cohort of patients with bradycardia and AF, arterial embolism was common in patients with ischemic cardiopathy, hypertension, diabetes mellitus, and in patients with known stroke risk factors. Atrial fibrillation occurrences longer than one day were independently associated with embolic events.

Understanding Atrial Symptom Reports: Objective versus Subjective Predictors

Atrial fibrillation (AF) is the most common cardiac arrhythmia and is associated with a variety of symptoms such as dizziness, palpitations, shortness of breath, and other signs of heart failure, which in turn impact quality of life (QOL). Implantable cardioverter defibrillators with atrial therapies (ICDs-ATs) have been shown to reduce AF symptoms and improve QOL in select AF samples. This study examined the strength of relationships between objective (device-detected AF events) versus subjective (emotional symptoms) data and AF symptoms (number) reported as part of the Patient Atrial Shock Survey of Acceptance and Tolerance Study (N = 96, 72% men, M age = 65, SD = 12). Depression and anxiety were assessed via the Center for Epidemiological Studies--Depression Scale and the-State Trait Anxiety Inventory. AF disease burden was measured via a number of device-detected AF episodes and the Atrial Tachyarrhythmia Symptom Severity Scale. Hierarchical multiple regression analysis indicated that negative emotions accounted for a significant 13.2% of unique variance in AF symptom score (F change (1, 54) = 9.625, P = 0.003). On the other hand, the number of device-detected AF episodes accounted for non-significant 8.2% of unique variance in the AF symptom score (P = 0.167). The full model explained 25.7% of the variance in AF symptom score (F(6, 54) = 3.110, P = 0.011). Specifically, greater number of treated AF episodes (beta= 0.251, P = 0.043) and higher levels of negative emotions (beta= 0.369, P = 0.003) predicted greater number of reported AF symptoms. Therefore, psychological distress may be a significant confounding factor affecting patient's report of AF symptoms rather than the actual experience of recurrent AF episodes.