Prior History Of Atrial Fibrillation Research Articles

The Arrhythmic Substrate for Atrial Fibrillation in Patients with Mitral Regurgitation.

Patients with severe mitral regurgitation commonly develop atrial fibrillation. The precise mechanisms of this relationship remain unknown. The objective of this study was to apply noninvasive electrocardiographic imaging of the atria during sinus rhythm to identify changes in atrial electrophysiology that may contribute to development of atrial fibrillation in patients with severe mitral regurgitation referred for mitral valve surgery. Twenty subjects (9 atrial fibrillation and mitral regurgitation, 11 mitral regurgitation alone) underwent electrocardiographic imaging. Biatrial electrophysiology was imaged with activation maps in sinus rhythm. The reconstructed unipolar electrograms were analyzed for voltage amplitude, number of deflections and conduction heterogeneity. In subjects with mitral regurgitation, left atrial biopsies were obtained at the time of surgery. Results: Subjects with history of atrial fibrillation demonstrated prolonged left atrial conduction times (110±25 ms vs. mitral regurgitation alone (85±21), p=0.025); right atrial conduction times were unaffected. Variable patterns of conduction slowing were imaged in the left atria of most subjects, but those with prior history of atrial fibrillation had more complex patterns of conduction slowing or unidirectional block. The presence of atrial fibrillation was not associated with the extent of fibrosis in atrial biopsies. Detailed changes in sinus rhythm atrial electrophysiology can be imaged noninvasively and can be used to assess the impact and evolution of atrial fibrillation on atrial conduction properties in patients with mitral regurgitation. If replicated in larger studies, electrocardiographic imaging may identify patients with mitral regurgitation at risk for atrial fibrillation and could be used to guide treatment strategies.

Cardiac Toxicity in Central Non-Small Cell Lung Tumors treated with Stereotactic Body Radiation Therapy (SBRT) – Is there a “No-Flutter Zone”?

Cardiac toxicity has been well-described following conventional radiotherapy to the thorax; however, the long-term cardiac effects of ablative stereotactic body radiotherapy (SBRT) doses are unknown. Furthermore, appropriate dose constraints to the heart to minimize long-term cardiac toxicity have not been well characterized, nor has the potential effect of pre-existing cardiac disease on toxicity risk. We conducted an institutional database review to assess cardiac events in patients treated with SBRT for central early-stage lung cancer or metastasis within 5 cm of the heart, prior to the year 2017 to allow sufficient follow up. Descriptive statistics were used to report patient and treatment information, and cardiac events. Linear regression was used to assess the relationship between cardiac events and age, gender, cardiac history, smoking history, tumor size, and cardiac dose (mean, maximum, volume receiving, 5Gy, 10Gy and 30Gy). Forty-seven patients met criteria, 39 patients with primary NSCLC, and 8 with central lung metastasis. Median follow up time after SBRT was 21.5 months (range 2.1-61). Mean tumor diameter was 4.3 cm (range 2.5-7.4). Seventeen (36.2%) patients had a pre-existing cardiac history, most commonly ischemia or MI. Median distance from the tumor to heart in all included patients was 1.8 cm (range 0.0-4.9). Eight of 47 patients (12.1%) had a cardiac event following SBRT (2 de novo, 6 in patients with cardiac history), at a median time of 30 months (range 17-34). Six of the 8 patients had tumors located within 1 cm of the heart. Maximum heart doses ranged from 20.8Gy to 61.7Gy (median 51 Gy), while MHD ranged from 2.3-7.8Gy (median 5.6Gy). Only one cardiac death attributed to atrial fibrillation causing stroke occurred, in a patient with a prior history of atrial fibrillation. On univariate analysis, previous history of cardiac disease (OR 4.4; p = 0.03) was with an increased risk of cardiac events. On multivariate analysis, there was a trend towards association between cardiac history and cardiac events, however this was not statistically significant (OR 5.2, p = 0.1). Mean and maximum heart dose, V5, V10, V30, were not significantly associated with cardiac disease (see Tables 5 and 6). Overall, current SBRT dose constraints for the heart appear to be safe with low risk of cardiac events, and our findings do not support previous reports of an association between cardiac events, death and SBRT dose. Cardiac history was the main predictor of cardiac event post-SBRT, and this should be considered when treating patients with SBRT for central tumors in close proximity to the heart.

HATCH VERSUS CHA2DS2-VASC SCORE AS PREDICTORS OF NEW-ONSET ATRIAL FIBRILLATION AFTER CATHETER ABALTION OF TYPICAL ATRIAL FLUTTER

Catheter ablation of cavotricuspid isthmus (CTI) is recommended procedure for typical atrial flutter (AFL), but patients remain at an increased risk for new-onset of atrial fibrillation (AF). Previously HATCH score was proposed to be independent predictor for both AF recurrence after AF ablation and incidence of new-onset of AF after typical AFL ablation. However, there are limited date to compare better predictability of new-onset of AF between the HATCH score and CHA2DS2-VASc score after typical AFL ablation without a prior history of AF.

CHA2DS2-VASc Score as a Predictor of New-Onset Atrial Fibrillation After Catheter Ablation of Typical Atrial Flutter.

PurposeCavotricuspid isthmus (CTI) ablation is an effective procedure for typical atrial flutter (AFL), but patients remain at an elevated risk for developing new atrial fibrillation (AF). Currently, there are limited data on the utility of CHA2DS2-VASc score to predict new-onset AF after typical AFL ablation. In this study, we assessed whether the CHA2DS2-VASc score is a useful predictor of new-onset AF after CTI ablation in typical AFL patients without a prior history of AF.MethodsThis was a retrospective study of 103 typical AFL patients with no prior history of AF, who underwent successful CTI ablation. The endpoint was occurrence of new-onset AF during follow-up.ResultsDuring a mean follow-up period of 24.6 ± 16.9 months, at least one episode of AF occurred in 33 (32%) patients. Multivariate Cox regression analysis revealed that CHA2DS2-VASc score (hazard ratio = 1.736; 95% confidence interval = 1.370–2.201; P < 0.001) was significantly associated with postablation new-onset AF (area under the curve = 0.797). A cutoff value of three stratified these patients into two groups with different incidences of postablation new-onset AF (67.9 vs. 18.7%, P < 0.001).ConclusionThe CHA2DS2-VASc score is a useful tool for the prediction of new-onset AF after ablation of typical AFL. Patients with CHA2DS2-VASc score ≥3 are more likely to develop new-onset AF and should be monitored more closely.

High incidence of subclinical atrial fibrillation in patients with syncope monitored with implantable cardiac monitor

ObjectiveThe use of implantable cardiac monitors (ICM) is highly useful in syncope workup. Latest-generation devices can detect asymptomatic episodes of atrial fibrillation. The main objective of this study was to determine the incidence of subclinical atrial fibrillation (AF) detected in a patient population undergoing prolonged electrocardiographic monitoring with an ICM for the etiological workup of syncope. MethodsProspective observational study carried out in a tertiary hospital from April 2014 to October 2019. All consecutive adult patients monitored with a latest-generation ICM for syncope with no prior history of AF were included in the analysis. ResultsOf a total of 509 ICMs implanted during the study period, 208 patients fulfilled the inclusion criteria. 42 patients (20.2%) were found to have AF on ICM. The incidence of AF was 11.7 cases per 100 person-years (95% CI: 8.7–15.9 per 100 person-years). The median burden of AF was 0.2% (IQR 0–0.8%). Age, the presence of hypertension, chronic kidney disease, the size of the septum and left atrium on electrocardiogram and the presence of broad QRS on baseline electrocardiogram were predictors for the appearance of AF in the univariate analysis. ConclusionThe incidental finding of atrial fibrillation in patients with syncope monitored with ICM is common. The burden of AF is low, and it is generally subclinical. These findings create added value for the use of ICM in the workup for syncope, although further studies are needed to determine the clinical benefit of documenting subclinical AF.

Transsulfuration metabolites and the association with incident atrial fibrillation – An observational cohort study among Norwegian patients with stable angina pectoris

Background/aimPlasma total homocysteine (tHcy) is elevated in patients with persistent vs. paroxysmal atrial fibrillation (AF), and has been related to increased risk of new-onset AF. Homocysteine is degraded to cystathionine (Cysta) and cysteine (Cys). All three metabolites have been linked to potential proarrhythmic traits such as inflammation and atrial fibrosis. We evaluated the prospective association between these metabolites and new-onset AF among patients with suspected stable angina pectoris. MethodsInformation regarding AF was obtained by linking patient data to national health registries. Risk associations were explored by Cox regression and potential improvements in risk reclassification were calculated by the continuous net reclassification index (NRI > 0). ResultsAt baseline, 3535 patients without any prior history of AF were included. During median follow-up of 7.4 years, 392 patients (10.2%) were registered with incident AF. Higher plasma tHcy and tCys were associated with increased risk of incident AF [age and gender adjusted HRs (95% CI) per 1 log transformed SD 1.23 (1.12–1.35) and 1.23 (1.11–1.38)]; multivariate adjustment yielded similar results. Plasma tHcy and tCys also improved reclassification of patients (NRI > 0 (95% CI)) for tHcy 0.118 (0.02–0.22) and tCys 0.107 (0.002–0.21). No association was seen between plasma Cysta and incident AF. ConclusionPlasma tHcy and tCys, but not Cysta, were associated with, and improved risk classification of, new-onset AF among patients with stable angina pectoris. Our results motivate further studies to explore the relationship between homocysteine metabolism and cardiac arrhythmias.

Trends and predictors of early ablation for Atrial Fibrillation in a Nationwide population under age 65: a retrospective observational study

BackgroundCatheter ablation (CA) has emerged as an effective treatment for symptomatic atrial fibrillation (AF). However practice patterns and patient factors associated with referral for CA within the first 12 months after diagnosis are poorly characterized. This study examined overall procedural trends and factors predictive of catheter ablation for newly-diagnosed atrial fibrillation in a young, commercially-insured population.MethodsA large nationally-representative sample of patients age 20 to 64 from years 2010 to 2016 was studied using the IBM MarketScan® Commercial Database. Patients were included with a new diagnosis of AF in the inpatient or outpatient setting with continuous enrollment for at least 1 year pre and post index visit. Patients were excluded if they had prior history of AF or had filled an anti-arrhythmic drug (AAD) in the pre-index period.ResultsEarly CA increased from 5.0% in 2010 to 10.5% in 2016. Patients were less likely to undergo CA if they were located in the Northeast (OR: 0.80, CI: 0.73–0.88) or North Central (OR: 0.91, CI: 0.83–0.99) regions (compared with the West), had higher CHA2DS2-VASc scores, or had Charlson Comorbidity Index (CCI) score of 3 or greater (OR: 0.61; CI: 0.51–0.72).ConclusionsCA within 12 months for new-diagnosed AF increased significantly from 2010 to 2016, with most patients still trialed on an AAD prior to CA. Patients are less likely to be referred for early CA if they are located in the Northeast and North Central regions, have more comorbidities, or higher CHA2DS2-VASc scores.

Hypertension prevalence but not control varies across the spectrum of risk in patients with atrial fibrillation: A RE-LY atrial fibrillation registry sub-study

BackgroundAlthough hypertension is the most common risk factor for atrial fibrillation (AF), whether blood pressure (BP) control varies across the spectrum of stroke risk in patients with AF or by adequacy of their thromboprophylaxis management is unclear.MethodsWe examined data from the RE-LY AF registry conducted at 164 emergency departments (EDs) in 47 countries between December 2007 and October 2011.ResultsOf the 15,400 patients in the registry, we analyzed the 9929 (mean age 67.5 years, 51.9% men) with a prior history of AF and complete BP data. While 6508 (66.5%) AF patients had hypertension, the prevalence varied widely depending on comorbidity profiles: from 45.4% in those without other cardiovascular risk factors to 82.5% in those with AF and diabetes. Although 93.9% of AF patients with hypertension were on at least one antihypertensive agent, fewer than half had BP levels ≤ 140/90 with no difference across risk profiles: 45.9% of those with NVAF and CHADS2 scores of 1 and 45.6% of those with NVAF and CHADS2 scores of 2 or more (46.9% and 45.3% for CHA2DS2-VASc scores of 1 versus 2 or more). BP control rates were not significantly better in those NVAF patients receiving guideline concordant thromboprophylaxis management (47.2%, aOR 1.03, 95%CI 0.89–1.20) than in those not receiving guideline-concordant antithrombotic therapy (45.3%).ConclusionsHypertension was common in patients with AF but BP control rates were sub-optimal and varied little across the spectrum of stroke risk or by adequacy of thromboprophylaxis. This highlights the need for an increased focus on total atherosclerotic risk rather than just thromboprophylaxis management in AF patients.

P970 Significant differences in atrial structural and functional parameters leading to differing mechanisms of atrial fibrillation in athletes compared to non-athletes

Abstract Background/Introduction: There is an increased incidence of atrial fibrillation (AF) in endurance athletes. We sought to evaluate the likely mechanistic basis for this phenomenon. Methods 36 endurance athletes in sinus rhythm, with a previous history of AF (ATH-AF) were compared to age and gender matched endurance athletes with no prior history of AF (ATH), non athletes with paroxysmal AF (NONATH-AF) and age and gender matched healthy controls (CONTROL). A detailed transthoracic echocardiogram was performed with all groups in sinus rhythm, with detailed left atrial (LA) and left ventricular (LV) measurements, including strain analysis. Results All athletes had increased LA and LV size when compared with healthy controls (Table 1). Non athletes with paroxysmal AF had increased LA size when compared with controls. However, indexed LA/LV ratio was preserved in athletes and similar to healthy individuals, whilst AF patients had significantly increased LA/LV ratio. Athletes with AF had higher e’ velocity and lower E/e’, whereas e’ was reduced and E/e’ elevated in non-athlete AF patients. Athletes had impaired LA reservoir and contractile strain, and reduced LV global longitudinal strain (GLS) compared with healthy controls. Conclusions Compared to healthy controls, athletes have reduced LA and LV strain, with preserved LV diastolic function and LA/LV ratio. In contrast, altered diastolic function with differential increase in LA volume was observed in AF patients. The increased risk of AF in athletes is likely mediated by different mechanistic processes other than an atrial myopathy consequent to diastolic dysfunction as observed in non-athletes with AF. Table 1. LA and LV parameters Parameter ATH-AF ATH NONATH-AF CONTROL P value LVEDV indexed (ml/m2) 84 ± 12 79 ± 14 57 ± 10 51 ± 13 &amp;lt;0.001 LVESV indexed (ml/m2) 35 ± 6 34 ± 7 25 ± 8 27 ± 33 0.02 LV ejection fraction (%) 58 ± 4 56 ± 4 56 ± 10 58 ± 8 0.586 LV global longitudinal strain (%) 19.2 ± 1.7 18.9 ± 2.1 21 ± 3.1 21.7 ± 2.9 &amp;lt;0.001 e’ vel (cm/s) 10 ± 2 10 ± 3 8 ± 2 9 ± 2 0.007 E/e’ 5.7 ± 1.3 5.9 ± 1.8 9.1 ± 3.3 7.5 ± 1.5 &amp;lt;0.001 LAV max indexed (ml/m2) 45 ± 11 43 ± 12 38 ± 11 27 ± 8 &amp;lt;0.001 Indexed LAV/LVEDV ratio 0.5 ± 0.1 0.6 ± 0.2 0.7 ± 0.2 0.5 ± 0.1 &amp;lt;0.001 LA reservoir strain (%) 27.2 ± 4.8 28.2 ± 3.7 27.9 ± 8.4 33.2 ± 7.0 &amp;lt;0.001 LA conduit strain (%) 14.2 ± 4.5 14.4 ± 4.0 14.9 ± 5.5 16.6 ± 6.3 0.182 LA contractile strain (%) 13.0 ± 3.1 13.8 ± 3.6 13.0 ± 5.1 16.6 ± 3.1 &amp;lt;0.001 LV = left ventricular, LAV = left atrial volume, LA = left atrial

Advanced interatrial block: A predictor of covert atrial fibrillation in embolic stroke of undetermined source

AimsOne third of ischemic strokes are of unknown etiology. Interatrial block (IAB) is a marker of atrial electromechanical dysfunction that may predispose to the development of atrial fibrillation (AF). We hypothesized that IAB, especially in its advanced form, could be a marker of covert AF in patients with embolic stroke of undetermined source (ESUS). MethodsWe reviewed a single center cohort of ESUS patients with no prior history of AF. According to P-wave analysis of baseline ECG we distinguished 3 groups: normal P-wave duration (P-wave < 120 ms), partial IAB (P-IAB, P-wave ≥ 120 ms) and A-IAB (A-IAB, P-wave ≥ 120 ms with biphasic morphology in inferior leads). Follow-up was done 1, 6 and 12 months after discharge; then every 6 months. AF episodes, frequent premature atrial contractions (PACs) (>1%) and atrial tachyarrhythmias (runs of >3 consecutive PACs) were detected on 24 h Holter. The primary endpoint was new-onset AF detection on follow-up by any means. ResultsA high prevalence of both P-IAB (n = 30, 40%) and A-IAB (n = 23, 31%) was found in 75 ESUS patients. After a 521 day mean follow-up, 14 patients (19%) were diagnosed of AF. A-IAB independently predicted AF diagnosis (p =0.042) on follow-up. 24 h Holter analysis showed greater frequency of PACs and atrial tachyarrhythmia episodes in patients with IAB (p = 0.0275). ConclusionsIn this hypothesis-generating study, A-IAB in the setting of ESUS is an independent risk predictor of covert AF. Although additional randomized clinical trials are warranted, A-IAB identifies ESUS patients with advanced atrial disease that could potentially benefit from early oral anticoagulation in secondary prevention.

Potential Utility of Neurosonology in Paroxysmal Atrial Fibrillation Detection in Patients with Cryptogenic Stroke.

Background: Occult paroxysmal atrial fibrillation (PAF) is a common and potential treatable cause of cryptogenic stroke (CS). We sought to prospectively identify independent predictors of atrial fibrillation (AF) detection in patients with CS and sinus rhythm on baseline electrocardiogram (ECG), without prior AF history. We had hypothesized that cardiac arrhythmia detection during neurosonology examinations (Carotid Duplex (CDU) and Transcranial Doppler (TCD)) may be associated with higher likelihood of AF detection. Methods: Consecutive CS patients were prospectively evaluated over a six-year period. Demographics, clinical and imaging characteristics of cerebral ischemia were documented. The presence of arrhythmia during spectral waveform analysis of CDU/TCD was recorded. Left atrial enlargement was documented during echocardiography using standard definitions. The outcome event of interest included PAF detection on outpatient 24-h Holter ECG recordings. Statistical analyses were performed using univariate and multivariate logistic regression models. Results: A total of 373 patients with CS were evaluated (mean age 60 ± 11 years, 67% men, median NIHSS-score 4 points). The rate of PAF detection of any duration on Holter ECG recordings was 11% (95% CI 8%–14%). The following three variables were independently associated with the likelihood of AF detection on 24-h Holter-ECG recordings in both multivariate analyses adjusting for potential confounders: age (OR per 10-year increase: 1.68; 95% CI: 1.19–2.37; p = 0.003), moderate or severe left atrial enlargement (OR: 4.81; 95% CI: 1.77–13.03; p = 0.002) and arrhythmia detection during neurosonology evaluations (OR: 3.09; 95% CI: 1.47–6.48; p = 0.003). Conclusion: Our findings underline the potential utility of neurosonology in improving the detection rate of PAF in patients with CS.

Frontline Treatment with Ibrutinib with Rituximab (IR) Combination Is Highly Effective in Elderly (≥65 years) Patients with Mantle Cell Lymphoma (MCL) - Results from a Phase II Trial

Frontline Treatment with Ibrutinib with Rituximab (IR) Combination Is Highly Effective in Elderly (≥65 years) Patients with Mantle Cell Lymphoma (MCL) - Results from a Phase II Trial

Association of Total Reproductive Years With Incident Atrial Fibrillation, and Subsequent Ischemic Stroke in Women With Natural Menopause.

The association of lifetime exposure to endogenous sex hormone with incident atrial fibrillation (AF) and subsequent ischemic stroke has never been studied. This study involved 4 638 299 natural postmenopausal waomen aged ≥40 years without prior history of AF and with national breast cancer check-up between January 1, 2009 and December 31, 2014. The primary end point was incident AF, and the secondary end point was subsequent ischemic stroke once AF has developed. Cox proportional hazard regression analysis was used to estimate the risk of end points. During the mean follow-up of 6.3 years, shorter total reproductive years (<30 years) were associated with 7% increased risk of AF after adjusting for confounding variables (adjusted hazard ratio [aHR], 1.07 [95% CI, 1.05-1.09]). Risk of AF declined progressively with every 5-yearly increment in total reproductive years (P-for-trend <0.001). However, the prolonged (≥2 years) use of hormone replacement therapy after menopause was paradoxically associated with a 3% increase in AF risk (aHR, 1.03 [95% CI, 1.01-1.05]). For the secondary end point analysis, the risk of ischemic stroke after AF development significantly decreased with each 5-yearly increment in total reproductive years (with <30 years as reference; aHR, 0.93 [95% CI, 0.88-0.99] for 30-34 years; aHR, 0.84 [95% CI, 0.79-0.89] for 35-39 years; and aHR, 0.88 [95% CI, 0.80-0.97] for ≥40 years, P-for-trend <0.001). In women with natural menopause, shorter lifetime exposure to endogenous sex hormone, that is, shorter total reproductive years, was significantly associated with a higher risk of AF and subsequent ischemic stroke. Paradoxically, prolonged exogenous hormone replacement therapy increased the risk of incident AF.

Impact of Pre-Existing and New-Onset Atrial Fibrillation on Outcomes After Transcatheter Aortic Valve Replacement

ObjectivesThis study sought to evaluate impact of new-onset and pre-existing atrial fibrillation (AF) on transcatheter aortic valve replacement (TAVR) long-term outcomes compared with patients without AF. BackgroundPre-existing and new-onset AF in patients undergoing TAVR are associated with poor outcomes. MethodsThe study identified 72,660 patients ≥65 years of age who underwent nonapical TAVR between 2014 and 2016 using Medicare inpatient claims. History of AF was defined by diagnoses on claims during the 3 years preceding the TAVR, and new-onset AF was defined as occurrence of AF during the TAVR admission or within 30 days after TAVR in a patient without prior history of AF. Outcomes included all-cause mortality, and readmission for bleeding, stroke, and heart failure (HF). ResultsOverall, 40.7% had pre-existing AF (n = 29,563) and 6.8% experienced new-onset AF (n = 2,948) after TAVR. Mean age was 81.3, 82.4, and 83.8 years in patients with no AF, pre-existing, and new-onset AF, respectively. Pre-existing AF patients had the highest burden of comorbidities. After follow-up of 73,732 person-years, mortality was higher with new-onset AF compared with pre-existing and no AF (29.7, 22.6, and 12.8 per 100 person-years, respectively; p < 0.001). After adjusting for patient characteristics and hospital TAVR volume, new-onset AF remained associated with higher mortality compared with no AF (adjusted hazard ratio: 2.068, 95% confidence interval [CI]: 1.92 to 2.20; p < 0.01) and pre-existing AF (adjusted hazard ratio: 1.35; 95% CI: 1.26 to 1.45; p < 0.01). In competing risk analysis, new-onset AF was associated with higher risk of bleeding (subdistribution hazard ratio [sHR]: 1.66; 95% CI: 1.48 to 1.86; p < 0.01), stroke (sHR: 1.92; 95% CI: 1.63 to 2.26; p < 0.01), and HF (sHR: 1.98; 95% CI: 1.81 to 2.16; p < 0.01) compared with pre-existing AF. ConclusionsIn patients undergoing TAVR, new-onset AF is associated with increased risk of mortality and bleeding, stroke, and HF hospitalizations compared with pre-existing AF or no AF.

P6545Pacing as new predictor for atrial high rate episodes in patients with dual-chamber pacemakers and no history of atrial fibrillation

Abstract Introduction Both atrial and ventricular pacing (AP/VP) have been related to a higher risk of clinical atrial fibrillation (AF) documented on ECG. Subclinical AF is detected as atrial high rate episodes (AHRE) by cardiac implantable electronic devices and is related to a higher risk of stroke. Purpose The aim of this study was to determine whether the percentage of AP and/or VP in patients with pacemakers and no history of AF is related with the future development of subclinical AF (AHRE) and/or clinical AF (ECG documented). Methods From February 2012 to September 2015 we recruited patients with dual chamber pacemakers and no prior history of AF. Patients were followed at 3 months and every year then after. Subclinical AF, clinical AF and cardiovascular events were registered. AHRE (subclinical AF) was defined as an episode of atrial rate ≥225 bpm with a minimum duration of 5 min. Clinical AF was defined as ECG documented AF. Percentage of AP/VP was determined as the mean AP/VP during the first three visits. Mortality and cardiovascular events (including AF, stroke and hospitalization for heart failure) were also recorded. Results 249 patients (57% men; 75±9 years-old) were included. Mean time from pacemaker implantation was 9 months and the main indication was AV-block in 53% of the patients. Mean CHA2DS2-VASc score was 3.5±1.5. After a mean follow-up of 33±11 months, 38.5% of patients developed subclinical AF and 10.4% clinical AF. Patients with AP≥50% presented significantly higher risk of AHRE (62.5% vs 32.3%, OR 3.48; 95% CI [1.93–6.4] p&lt;0.01) and clinical AF (18.7% vs 8.6%, OR 2.4; 95% CI [1.05–5.52] p&lt;0.05). Patients with VP≥50% presented significantly higher risk of AHRE (46.4% vs 31.6%, OR 1.87; 95% CI [1.10–3.24] p&lt;0.05) and clinical AF (25.9% vs 9.7%, OR 2.7; 95% CI [1.13–7.72] p&lt;0.05). The percentage of AP and VP were not related to a higher risk of cardiovascular events or mortality. Multivariate analysis showed that AP≥50% was an independent predictor for AHRE (OR 2.4; 95% CI [1.19–4.97] p=0.014). Conclusions Pacing is related to a higher risk for developing subclinical and clinical AF in patients with dual-chamber pacemakers and no history of previous AF. Our data suggest, that patients presenting a high percentage of AP and VP should be closely followed during routinely pacemaker check-ups assessing for subclinical AF, especially in those with AP ≥50%.

Abstract 759: Circulating Preoperative microRNA-29, Biomarkers of Collagen Synthesis, and Age Predictive of Postoperative Atrial Fibrillation After Coronary Artery Bypass Grafting

Background: Postoperative atrial fibrillation (PoAF) is a common complication occurring in 35-50% patients within 2-3 days after cardiac surgery. Identification of patients, especially those with no prior history of atrial fibrillation before surgery, is a challenge. A pre-existing atrial substrate appears to be an important factor in the development of PoAF. The aim of this study was to assess the role of biomarkers in identifying patients at risk of PoAF in a pathophysiology-based risk predictive model by combining clinical and biochemical risk factors. Methods: Preoperative blood from patients undergoing cardiac surgery with no previous history of AF was assessed for circulating levels of biomarkers reflecting collagen synthesis/degradation and extracellular matrix remodeling using ELISA. Reverse transcriptase polymerase chain reaction assessed microRNA29 in the serum and correlated to extent of atrial fibrosis. Echocardiographic evaluation of LA mechanics was performed preoperatively using M-mode, 2D Doppler, and 3D Speckle tracking. Results: Out of 55 patients, 31 patients (56.4%) who developed PoAF after surgery during their hospital stay were older in age (70.0 ± 4.0 years vs.63.4±9.9; p&lt;0.01) with abnormal global longitudinal stain (6.9±0.69 vs.10.9±0.93, p=0.007), higher amino-terminal peptide procollagen III (PIIINP) levels (101.1±42.7 vs.36.6±20.0; p=0.043) with increased collagen to myocardial ratio (0.20±0.09 vs. 0.09±0.01, p= 0.026), and reduced preoperative circulating microRNA-29a, -29b and -29c levels. By combining the clinical risk factors, circulating biochemical and molecular biomarkers, we developed a model that identified PoAF patients (AUC=0.7987; 95% CI, 0.6174—0.98) with reduced preoperative atrial ejection fraction (32±2% vs. 42±2 %; p=0.01) as an independent risk factor for PoAF. Conclusion: Our study developed a noninvasive tool to identify those who are at risk for new-onset PoAF in patients with no previous history of AF when combining age, biomarkers of collagen synthesis and microRNA-29a.

Electrocardiomatrix Facilitates Accurate Detection of Atrial Fibrillation in Stroke Patients.

Background and Purpose- Cardiac telemetry is a routine part of inpatient ischemic stroke/transient ischemic attack evaluation to assess for atrial fibrillation (AF). Yet, tools to assist stroke clinicians in the evaluation of the large quantities of telemetry data are limited. The investigators developed a new method to evaluate electrocardiographic signals, electrocardiomatrix, that was applied to stroke unit telemetry data to determine its feasibility, validity, and usefulness. Electrocardiomatrix displays telemetry data in a 3-dimensional matrix that allows for more accurate and less time consuming P-wave analysis. Methods- In this single-center, prospective, observational study conducted in a stroke unit, all telemetry data from ischemic stroke and transient ischemic attack patients were collected (April 2017-January 2018) for examination facilitated by electrocardiomatrix. AF>30 seconds was identified through review of electrocardiomatrix-generated matrices by a nonphysician researcher. Electrocardiomatrix results were compared with the clinical team's medical record documentation of AF identified through telemetry. A study cardiologist reviewed the standard telemetry associated with all AF episodes identified by electrocardiomatrix and each case of disagreement. Results- Telemetry data (median 46 hours [interquartile range: 22-90]) were analyzed among 265 unique subjects (88% ischemic stroke). Electrocardiomatrix was successfully applied in 260 (98%) of cases. The positive predictive value of electrocardiomatrix compared with the clinical documentation was 86% overall and 100% among the subset with no prior history of AF. For the 5 false-positive and 5 false-negative cases, expert overview disagreed with the clinical documentation and confirmed the electrocardiomatrix-based diagnosis. Conclusions- The application of electrocardiomatrix to stroke unit-acquired telemetry data is feasible and appears to have superior accuracy compared with traditional monitor analysis by noncardiologists.

New-onset atrial fibrillation is associated with 28-day mortality among patients with sepsis

Background: New-onset atrial fibrillation (NO-AF) has been associated with adverse outcomes in sepsis. The definition of sepsis is based on organ dysfunction by use of the Sequential Organ Failure Assessment (SOFA) score. However, adult patients with suspected infection can be identified as being more likely to have poor outcomes typical of sepsis if they have at least two qSOFA criteria. We have analyzed the occurrence of NO-AF on admission and 28-day mortality among infected patients with two or more qSOFA criteria on admission.&#x0D; Methods: A prospective cohort study of infected patients aged 18 years or older admitted to the emergency department (ED) of Slagelse Hospital during 01.10.2017 – 31.03.2018 (171 days). The population in the area was 198.000. All patients with suspected or documented infection on arrival, and treated with antibiotics, were included. NO-AF was defined as episodes of atrial fibrillation (AF) within 4 hours from admission documented on a 12-lead electrocardiogram and without a history of prior AF. We used a logistic regression analysis to adjust for the potential confounding of the association between NO-AF and 28-day mortality. Survival status was obtained from the Danish Civil Registration System.&#x0D; Results: A total of 2.168 infected patients with median age of 73.1 years were included, and 181 (8.3%; 95% CI 4.7-13.3) fulfilled at least two qSOFA criteria on admission. The incidence of sepsis based on qSOFA criteria was estimated to 194/100,000. A total of 15 (8.3%, 95% CI 4.7-13.3) qSOFA patients developed NO-AF. The 28-day mortality among all qSOFA patients was 17.1% (95% CI 11.9-23.4), 40.0% (95 % 16.3-67.7) among patients with NO-AF and 15.1% (95% CI 10.0-21.4) among patients without NO-AF). Unadjusted odds ratio for 28-day mortality among NO-AF patients was 3.8 (95% CI 1.2-11.50) and 4.6 (95% CI 1.4-15.3) after adjustment for several potential confounders.&#x0D; Conclusion: New-onset atrial fibrillation is independently associated with 28-day mortality among patients with qSOFA defined sepsis.

Atrial arrhythmias after pulmonary thromboendarterectomy.

Atrial arrhythmias (AAs) are common after cardiac surgeries including pulmonary thromboendarterectomy (PTE). This study was done to identify patients at highest risk of developing post-PTE AA and their length of stay (LOS). We reviewed 521 consecutive patients referred to University of California San Diego (UCSD) for PTE and examined their demographics as well as their baseline pulmonary hemodynamics to determine risk factors for AA. Overall, 24.2% of patients developed an AA after PTE. Patients who developed AA had a significantly longer Intensive Care Unit (ICU) LOS (median: 5 vs 3 days, P < 0.001) and postoperative LOS (median: 14 vs 9 days; P < 0.001). Patients who developed AA were more frequently male (63.2% male, P = 0.003), older (mean age 60.8 vs 50.7 years, P < 0.001), had a prior history of atrial fibrillation (80.2% of those who developed AA) and were more likely to have undergone concomitant Coronary Artery Bypass Graft (12.7% vs 6.6%, P = 0.028). Compared to those who did not develop AA, the cardiopulmonary bypass time was longer among those who developed AA (261.6 vs 253.8 minutes, P = 0.027). In a multivariate logistic regression model, the preoperative variables that predicted AA were age (odds ratio [OR], 1.058 per year, 95% confidence interval [CI]: 1.038-1.078), male sex (OR, 1.68, 95% CI: 1.06-2.64), prior AA (OR, 2.52, 95% CI: 1.23-5.15) and baseline right atrial pressure (OR, 1.039 per mm Hg, 95% CI: 1.000-1.079). While mortality rates were similar, patients who developed AA had more bleeding complications and more postoperative delirium. AA is common after PTE surgery. The strongest risk factors for AA after PTE included the previous history of AA, age and male sex. Development of AA was associated with longer lengths of stay and more postoperative complications.

Prophylactic pulmonary vein isolation during cavotricuspid isthmus ablation for atrial flutter: A meta-analysis.

Atrial arrhythmias (AA), including atrial fibrillation (AF), have been reported in patients after cavotricuspid isthmus (CTI) ablation for typical atrial flutter (AFL). Several studies have examined the effect of performing concomitant pulmonary vein isolation (PVI) with CTI on recurrent AA. These studies were analyzed to determine the overall effect of this approach on recurrent AA. PubMed and Google Scholar were searched for randomized trials comparing the incidence of AA after CTI versus CTI + PVI until June 2018. Only patients without prior history of AF were included in the recurrent AA analysis. All patients were included in the analyses of other clinical outcomes. Four randomized control trials were included in the meta-analysis. In the recurrent AA analysis, a total of 314 patients were randomized in the studies (n=158 CTI, n=156 CTI + PVI). Freedom from AA at 1 year was significantly higher in the CTI + PVI group versus CTI alone (odds ratio [OR] 0.25 [0.14, 0.44] 95% confidence interval [CI], P<0.00001). A total of 550 patients (n=336 CTI, n=214 CTI + PVI) were included in analyses for procedure time, fluoroscopy time, and complications rates. Procedure time and fluoroscopy time were significantly longer in the CTI + PVI group (mean difference [MD]: 103.31 min [94.40, 112.23] 95% CI, P<0.00001) and (MD: 16.47 min [14.89, 18.05] 95% CI, P<0.00001), respectively. Total complications were statistically similar between groups. This meta-analysis shows addition of a prophylactic PVI during CTI ablation significantly reduces recurrent AA at 1 year without significantly increasing major complications.