Asymptomatic Paroxysmal Atrial Fibrillation Research Articles

Skin sympathetic nerve activity in symptomatic and asymptomatic paroxysmal atrial fibrillation

BackgroundThe causes of symptoms in patients with paroxysmal atrial fibrillation (AF) remains unclear. ObjectiveThe purpose of this study was to correlate the magnitudes of skin sympathetic nerve activity (SKNA) with symptoms in patients with AF. MethodsWe prospectively enrolled patients with symptomatic paroxysmal AF for ambulatory electrocardiography and SKNA recording. Heart rhythms at the time of symptoms were categorized as AF or normal sinus rhythm (NSR). Maximal and average skin sympathetic nerve activity (aSKNA) and heart rate (HR) were compared between symptomatic and asymptomatic AF and NSR episodes using mixed effects models to account for within-patient correlations. ResultsAmong the 31 enrolled patients, 16 (52%) had at least 1 episode of AF, and 24 (77%) endorsed symptoms during the monitoring period. Compared with asymptomatic AF episodes, symptomatic AF episodes had higher maximal aSKNA (1.260 [interquartile range (IQR) 1.114–1.723] μV vs 1.108 [IQR 0.974–1.312] μV; P <0.001) and higher maximal HR (152 ± 24 bpm vs 132 ± 19 bpm; P <.001). Symptomatic NSR episodes were associated with higher maximal aSKNA (1.612 [IQR 1.287–2.027] μV vs 1.332 [IQR 1.033–1.668] μV; P = .001) and higher maximal HR (152 ± 24 bpm vs 105 ± 16 bpm; P <.001) than asymptomatic NSR episodes. Of the symptomatic episodes, 66 (73%) occurred during NSR and 24 (27%) during AF. All P values were obtained from mixed effects models. ConclusionSymptomatic episodes in patients with paroxysmal AF were more frequently associated with NSR than AF. Symptomatic AF and NSR episodes were associated with higher aSKNA than asymptomatic episodes. In patients with paroxysmal AF, symptoms correlate better with SKNA than heart rhythm.

Real-World Patent Foramen Ovale (PFO) Closure in Japan - 30-Day Clinical Outcomes From the AmplatzerTM PFO Occluder Japan Post-Marketing Surveillance Study.

The AmplatzerTM PFO Occluder was approved for marketing in Japan in May 2019, and the Amplatzer PFO Occluder Japan Post-marketing Surveillance (PFO Japan PMS) study was initiated in December 2019. This analysis presents 30-day clinical outcomes for PFO Japan PMS study patients.Methods and Results: PFO Japan PMS is a prospective single-arm non-randomized multicenter clinical study. Eligible patients were indicated for patent foramen ovale (PFO) closure and underwent an implant attempt with the AmplatzerTM PFO Occluder. Technical success was defined as successful delivery and release of the occluder; procedural success was defined as technical success with no serious adverse events (SAEs) within 1 day of the procedure. The primary safety endpoint includes predefined device- and/or procedure-related SAEs through 30 days after the procedure. From December 2019 to July 2021, 500 patients were enrolled across 53 Japanese sites. The mean (±SD) patient age was 52.7±15.4 years, and 29.8% of patients were aged >60 years. Technical and procedural success rates were both high (99.8% and 98.8%, respectively). Further, there was only one primary safety endpoint event (0.2%): an episode of asymptomatic paroxysmal atrial fibrillation that occurred 26 days after the procedure. In this real-world Japanese study with almost one-third of patients aged >60 years, PFO closure with the AmplatzerTM PFO Occluder was performed successfully and safely, with a low incidence of procedure-related atrial arrhythmias.

Characteristics of successful termination of atrial fibrillation by atrial antitachycardia pacing in patients with cardiac implantable electronic devices.

Asymptomatic paroxysmal atrial fibrillation (AF) is often found in patients implanted with cardiac implantable electronic devices (CIEDs). Second-generation atrial antitachycardia pacing (A-ATP) is effective in managing AF in patients implanted with CIEDs. The purpose of this study was to evaluate the efficacy and safety of A-ATP in patients implanted with CIEDs. This was a single-center retrospective study involving 91 patients (male 46 patients, mean age 74 ± 9years) implanted with Reactive A-ATP equipped devices (84 patients with pacemakers, 6 with ICDs, and 1 with a CRT-D). The AF burden, rate of AF termination, and details of the activation of the A-ATP were analyzed in each patient. During a mean follow-up period of 21 ± 13months, A-ATP was activated in 45 of 91 patients (49.5%). No patients had adverse events. Although the efficacy of the A-ATP varied among the patients, the median rate of AF termination was 44%. In comparison to the A-ATP start time, "0min" had a higher AF termination rate by the A-ATP (39.4% vs. 24.4%, P = 0.011). The rate of termination by the A-ATP was high for AF with a long cycle length and a relatively regular rhythm. A-ATP successfully terminated AF episodes in some patients implanted with CIEDs. The optimal settings of the A-ATP will be determined in future studies.

Current management of atrial fibrillation in routine practice according to the last ESC guidelines: an EHRA physician survey-how are we dealing with controversial approaches?

Although guidelines for the management of atrial fibrillation (AF) are regularly published, many controversial issues remain, limiting their implementation. We aim to describe current clinical practice among European Heart Rhythm Association (EHRA) community according to last guidelines. A 30 multiple-choice questionnaire covering the most controversial topics related to AF management was distributed through the EHRA Research Network, National Societies, and social media between January and February 2023. One hundred and eighty-one physicians responded the survey, 61% from university hospitals. Atrial fibrillation screening in high-risk patients is regularly performed by 57%. Only 42% has access to at least one programme aiming at diagnosing/managing comorbidities and lifestyle modifications, with marked heterogeneity between countries. Direct oral anticoagulants are the preferred antithrombotic (97%). Rhythm control is the preferred strategy in most AF phenotypes: symptomatic vs. asymptomatic paroxysmal AF (97% vs. 77%), low vs. high risk for recurrence persistent AF (90% vs. 72%), and permanent AF (20%). I-C drugs and amiodarone are preferred while dronedarone and sotalol barely used. Ablation is the first-line therapy for symptomatic paroxysmal AF (69%) and persistent AF with markers of atrial disease (57%) and is performed independently of symptoms by 15%. In persistent AF, 68% performs only pulmonary vein isolation and 32% also additional lesions. There is marked heterogeneity in AF management and limited accordance to last guidelines in the EHRA community. Most of the discrepancies are related to the main controversial issues, such as those related to AF screening, management of comorbidities, pharmacological treatment, and ablation strategy.

Coronary artery embolism as a silent killer due to asymptomatic paroxysmal atrial fibrillation.

Coronary artery embolism as a silent killer due to asymptomatic paroxysmal atrial fibrillation.

Accuracy of wristwatch-type photoplethysmography in detecting atrial fibrillation in daily life.

Detection of asymptomatic paroxysmal atrial fibrillation is challenging. Smartphone- or smartwatch-based photoplethysmography is efficient at detecting irregular rhythms using pulse waves but is too complex for older patients. We aimed to evaluate the detection accuracy of atrial fibrillation by a wristwatch-type continuous pulse wave monitor (PWM) in daily life. Patients at high risk of atrial fibrillation but with no history of atrial fibrillation (n = 163; mean CHADS2 score, 1.9) and patients with known atrial fibrillation (n = 123, including 34 with persistent atrial fibrillation) underwent PWM and telemetry electrocardiogram recording for 3 days. Risk of atrial fibrillation was judged using the 'Kyorin Atrial Fibrillation Risk Score', a scoring system based on previously reported atrial fibrillation risk scoring systems. The PWM assessed the presence of atrial fibrillation at 30 min intervals, and the results were compared with the telemetry electrocardiogram findings. The PWMs accurately diagnosed two patients with paroxysmal atrial fibrillation in the high-risk group. The PWMs accurately diagnosed 48 of the 55 patients with atrial fibrillation in the known-atrial fibrillation group. The PWM accuracy in detecting patients with atrial fibrillation was as follows: sensitivity, 98.0%; specificity, 90.6%; positive predictive value, 69.4%; negative predictive value, 99.5%. The respective values for intervals with atrial fibrillation were 86.9%, 98.8%, 89.6%, and 98.5%. The wristwatch-type PWM has shown feasibility in detecting atrial fibrillation in daily life and showed the possibility of being used as a screening tool.

Clinical and health economic evaluation of a post-stroke arrhythmia monitoring service.

Atrial fibrillation (AF) is a major cause of recurrent stroke and transient ischaemic attack (TIA) in the UK. As many patients can have asymptomatic paroxysmal AF, prolonged arrhythmia monitoring is advised in selected patients following a stroke or TIA. This service evaluation assessed the clinical and potential health economic impact of prolonged arrhythmia monitoring post-stroke using R-TEST monitoring devices. This was a prospective, case-controlled, service evaluation in a single health board in the North of Scotland. Patients were included if they had a recent stroke or TIA, were in sinus rhythm, and did not have another indication for, or contraindication to, oral anticoagulation. A health economic model was developed to estimate the clinical and economic value delivered by the R-TEST monitoring. Approval to use anonymised patient data in this service evaluation was obtained. During the evaluation period, 100 consecutive patients were included. The average age was 70 ± 11 years, 46% were female. Stroke was the presenting complaint in 83% of patients with the other 17% having had a TIA. AF was detected in seven of 83 (8.4%) patients who had had a stroke and one of 17 (5.9%) patients with a TIA. Health economic modelling predicted that adoption of R-TEST monitoring has a high probability of demonstrating both clinical and economic benefits. In conclusion, developing a post-stroke arrhythmia monitoring service using R-TEST devices is feasible, effective at detecting AF, and represents a probable clinical and economic benefit.

The relationship between morning blood pressure surge and asymptomatic episodes of paroxysmal atrial fibrillation in patients with systemic arterial hypertension.

Hypertension is a known risk factor for developing atrial fibrillation. However, there is limited data to investigate the association between morning blood pressure surge (MBPS) and paroxysmal atrial fibrillation (PAF). We conducted the present study to determine whether there is a relationship between asymptomatic PAF and MBPS and whether MBPS may be a predictor of asymptomatic PAF episodes. This prospective study comprised 264 adult patients who were newly diagnosed with essential hypertension or were previously diagnosed but not receiving regular antihypertensive therapy. We evaluated the patients in 2 groups according to their 24-h electrocardiography monitoring results: group 1 included patients who exhibited PAF (n = 32, 23 females/9 males; mean age 60.2 ± 7.4 years) and group 2 included patients with no signs of PAF as a control group (n = 232, 134 females/98 males; mean age 56.9 ± 9.4 years). We calculated the MBPS as the difference between mean systolic blood pressure (SBP) in the 2 h after getting up and the minimum nocturnal SBP. : MBPS values were significantly higher in group 1 than in group 2 (35.3 ± 7.0 vs. 22.0 ± 6.7, p < 0.001). MBPS was positively associated with left atrial diameter (LAD) (r = 0.441, p < 0.001), left ventricle mass index (LVMI) (r = 0.235, p < 0.001), the ratio of early (E) peak of mitral inflow velocity to early (Em) diastolic mitral annular velocity (E / Em) (r = 0.239, p < 0.001), 24-h mean (r = 0.270, p < 0.001) and daytime SBP (r = 0.291, p < 0.001). We determined a cut-off value for MBPS as 28.6 for predicting PAF episodes development and identified LAD and MBPS as independent risk factors for PAF. Patients who had larger MBPS were observed to have higher PAF incidence. MBPS values may be sensitive in predicting asymptomatic episodes of paroxysmal atrial fibrillation.

How Will Machine Learning Inform the Clinical Care of Atrial Fibrillation?

Machine learning applications in cardiology have rapidly evolved in the past decade. With the availability of machine learning tools coupled with vast data sources, the management of atrial fibrillation (AF), a common chronic disease with significant associated morbidity and socioeconomic impact, is undergoing a knowledge and practice transformation in the increasingly complex healthcare environment. Among other advances, deep-learning machine learning methods, including convolutional neural networks, have enabled the development of AF screening pathways using the ubiquitous 12-lead ECG to detect asymptomatic paroxysmal AF in at-risk populations (such as those with cryptogenic stroke), the refinement of AF and stroke prediction schemes through comprehensive digital phenotyping using structured and unstructured data abstraction from the electronic health record or wearable monitoring technologies, and the optimization of treatment strategies, ranging from stroke prophylaxis to monitoring of antiarrhythmic drug (AAD) therapy. Although the clinical and population-wide impact of these tools continues to be elucidated, such transformative progress does not come without challenges, such as the concerns about adopting black box technologies, assessing input data quality for training such models, and the risk of perpetuating rather than alleviating health disparities. This review critically appraises the advances of machine learning related to the care of AF thus far, their potential future directions, and its potential limitations and challenges.

Left atrial strain for predicting atrial fibrillation in hypertrophic cardiomyopathy

Patients with hypertrophic cardiomyopathy (HCM) are prone to develop atrial fibrillation (AF) due to diastolic dysfunction and left atrial (LA) remodeling. According to guidelines, 48-hour ambulatory ECG is recommended every 12–24 months in stable patients and every 6–12 months in case of LA dimension ≥ 45 mm or if new palpitations. The aim of this study is to investigate the predictive value of LA speckle tracking in detecting paroxysmal atrial fibrillation in HCM patients with enlarged left atrium. We enrolled 62 patients with HCM in sinus rhythm and LA diameter ≥ 45 mm. All patients had previously underwent 24 or 48-hour ambulatory ECG in the last 12 months without detecting any paroxysmal AF. In this study, all our patients underwent standard echocardiographic with left ventricular (LV) and LA speckle tracking examination followed by 7-days long-term ambulatory ECG monitoring. Among 62 patients, 19 patients (30.6%) were diagnosed with asymptomatic paroxysmal AF detected by 7-days long-term ambulatory ECG recorder (group1). In the same conditions, no paroxysmal FA was detected in the remaining 43 patients (group2). Group 1 patients showed no differences from group 2 patients with regards to mean ages, BMI, LV dimensions and ejection fraction, E/e’ ratio and even in LA diameter. However, they had significantly impaired left atrial strain indices with significantly lower LA conduit strain 12.15 ± 3.7% vs.17.34 ± 4.08% ( P < 0.01), lower LA reservoir strain 24.78 ± 4.49% vs. 32.18 ± 5.6% ( P < 0.001) and lower LA contractile strain −12.02 ± 3.91% vs. −15.16 ± 4.12% ( P < 0.01). Among HCM patients with enlarged LA, those with impaired LA strain indices were prone to higher risk for paroxysmal FA. Thus, LA strain may provide additional functional information for predicting AF susceptibility and may lead in case of impaired indices to propose prolonged ECG monitoring in order to enhance the detection of undiagnosed AF.

USEFULNESS OF LEFT VENTRICULAR SPECKLE TRACKING ECHOCARDIOGRAPHY IN DIAGNOSING PAROXYSMAL ATRIAL FIBRILLATION IN ISCHEMIC STROKE AND TRANSIENT ISCHEMIC ATTACK PATIENTS

Background: Asymptomatic paroxysmal atrial fibrillation (PAF) is often assumed to be the cause of the cryptogenic ischemic strokes (IS) or transient ischemic attacks (TIA). We examined whether measures obtained by 2D speckle tracking improves the diagnosis of PAF in patients with IS and TIA.

Cryptogenic ischemic stroke and prevalence of asymptomatic atrial fibrillation: a prospective study.

Atrial fibrillation is responsible for up to one-third of ischemic strokes, and is also associated with silent cerebral infarctions and transient ischemic attacks (TIAs). The self-terminating and often asymptomatic nature of paroxysmal atrial fibrillation (PAF) may lead to its underdiagnosis. A continuous and long-term heart rhythm monitoring can be useful in unmasking PAF episodes. Prevalence of asymptomatic PAF in patients suffering a cryptogenic stroke, at risk for atrial fibrillation but without any history of arrhythmia or palpitations, using a continuous electrocardiographic monitoring. One hundred and forty-two consecutive patients were admitted to the Stroke Unit of 'Città della Salute e della Scienza' Hospital of Turin between June 2010 and March 2013 and discharged with the diagnosis of ischemic cryptogenic stroke. Sixty fulfilled predefined inclusion criteria. Follow-up was carried on and completed for the 54 patients who consented to implantable loop recorder (ILR) implantation. After ILR implantation, trans-telephonic data were collected monthly. Atrial fibrillation episodes lasting more than 5 min were recorded in 25 patients (46%), median detection time was 5.4 months (range 1-18) and median duration of atrial fibrillation episodes was 20 h (range 7 min-8 days) with 19 patients (76%) remaining asymptomatic and the others experiencing weakness and dyspnoea but not palpitations. Long-term heart rhythm monitoring is successful in unmasking silent atrial fibrillation in 46% of patients suffering a cryptogenic stroke with concomitant atrial fibrillation risk factors, but without history of arrhythmia or palpitations.

Abstract 12671: Left Atrial Volumes Corrected for Heart Size are Superior Echocardiographic Measures for Diagnosing Paroxysmal Atrial Fibrillation in Ischemic Stroke and Transient Ischemic Attack Patients

Introduction: The underlying cause of ischemic strokes (IS) and transient ischemic attacks (TIA) is not identified in 25% of the cases. However, asymptomatic paroxysmal atrial fibrillation (PAF) is often assumed to be the cause of the cryptogenic IS or TIA Hypothesis: The aim of this study was to examine if echocardiographic measures of LA volume (LAV) corrected for the left ventricular (LV) length (LAVMax/Min/LV length) could predict PAF in patients with IS and TIA. Methods: We retrospectively included 218 patients who after acute IS or TIA underwent a transthoracic echocardiographic examination in sinus rhythm. Patients were designated as PAF-patients if they had one or more reported incidents of AF before or after their echocardiographic examination. Results: Patients in the PAF group were significantly older (62±13 vs. 52±14 years, p&lt;0.001), had higher CHA2DS2-VASc score (3.3±1.3 vs. 3.8±1.3, p=0.042) and higher National Institutes of Health Stroke Scale (NIHSS) score (2.9±4.9 vs. 1.4±3.3, p=0.016) than patients without PAF. Besides these, no other baseline characteristics (sex, hypertension, diabetes, cholesterol) were associated with PAF. None of the conventional echocardiographic parameters (LV ejection fraction, LV volumes, E/A-ratio, E-wave deceleration time, LAVmax) were significantly associated with PAF. However, the atrial measures corrected for LV length (LAVMax/LV length and LAVMin/LV length) were significantly higher (LAVMax/LV length: 7.6±3.3 mL/cm vs. 6.5± 2.0 mL/cm, p=0.009; LAVMin/LV length: 3.7± 2.1 mL/cm vs. 2.8±1.1 mL/cm, p&lt;0.001) in patients with PAF (Figure), even after adjustment for age, gender, CHA2DS2-VASc and NIHSS scores. Conclusion: In patients with IS and TIA, measures of LA size corrected for LV length are independently associated with the presence of PAF. Applying these may yield better risk stratification for PAF-presence in patients suffering cryptogenic IS and TIA.

CORRELATION BETWEEN HEART RHYTHM AND SYMPTOMS IN PATIENTS WITH PAROXYSMAL ATRIAL FIBRILLATION AFTER CATHETER ABLATION AND ANTIARRHYTHMIC THERAPY BASED ON DATA OBTAINED FROM IMPLANTABLE CARDIAC MONITORS

Purpose: to reveal a correlation between the symptoms and heart rhythm as well as to evaluate the incidence of symptomatic and asymptomatic paroxysmal atrial fibrillation (AF) in patients with paroxysmal AF after catheter ablation and antiarrhythmic drug therapy (AAD) through long-term observation based on data from implantable cardiac heart monitors (ICM). Materials and Methods: 92 patients with paroxysmal AF were randomly broken into two groups: 1) AF catheter ablation + ICM (Group I; n=46); 2) AAD + ICM (Group II; n=46). The data recorded by the device were matched against the symptoms diaries kept by the patients. Results: through the follow-up period (24 months), 17 (40%) patients of the catheter ablation Group and another 33 (71.8%) patients belonging to the AAD Group had AF relapse, whereas in 4 (23.5%) patients of the catheter ablation group and in 1 (3%) patients of the AAD group the paroxysms were asymptomatic. Only 30% of episodes recorded by the ICM in the AF catheter ablation + ICM Group and 78% of episodes in patients receiving AAD + ICM were found to be true AF paroxysms. Summary: the rhythm status did not match the patients’ symptoms in terms of AF, which was observed in 70% of the cases after catheter ablation and in 22% of cases in the AAD group. Asymptomatic AF was more common among the patients belonging to the catheter ablation group (23.5%) if compared to those who underwent AAD (3%). The subjective evaluation of the symptoms done by the patients regarding their arrhythmia did not reflect the true state of things related to the heart rhythm, which makes such evaluation not reliable if employed to judge the treatment efficiency.

Atrial fibrillation detection after cryptogenic stroke.

Ischemic stroke is a significant cause of mortality and of serious long-term morbidity. It is estimated that cryptogenic stroke (stroke whose underlying causes remain unknown despite a complete work-up,) accounts for about 20–40 % of all ischemic events, one quarter of which tend to be recurrent [1]. Paroxysmal and persistent atrial fibrillation (AF) is a well-recognized cause of ischemic stroke, and the risk may be reduced with anticoagulation. However, only 5 % of patients are diagnosed to have AF after an ischemic stroke. Indeed the use of traditional monitoring techniques may not detect episodes of asymptomatic paroxysmal AF, which might underlie some apparently ‘‘cryptogenic’’ strokes. Therefore, the most effective duration of ECG monitoring has not been determined by current guidelines [2]. Nowadays, external and implanted loop recorders may allow identification of silent AF, thus increasing AF detection rate. However, the effectiveness of prolonged heart rhythm monitoring in patients with cryptogenic stroke is still unproved [3, 4].

140 Does The Gore Septal Occluder Offer Excellent Closure of all PFO Phenotypes when Guided by 3D Imaging?

PurposeDevice characteristics are key in ensuring effective sealing of Patent Foramen Ovale (PFO). With a unique design and biocompatible material allowing device conformity to varying PFO anatomies, the Gore Septal...

9 Demographic and Electrocardiographic Characteristics to Predict Paroxysmal Atrial Fibrillation. Insights from an Implantable Loop Recorder Population

<h3>Introduction</h3> There is growing evidence that paroxysmal atrial fibrillation (PAF) carries the same thromboembolic stroke risk as permanent AF. With up to half of episodes asymptomatic PAF frequently eludes detection on routine 12-lead electrocardiogram (ECG) as well as Holter monitor testing. The loop recorder (LR) is emerging as a powerful tool in the diagnosis of asymptomatic PAF with impressive sensitivity and specificity, detecting paroxysmal AF in those with a normal ECG and Holter recording. LR use is not however entirely without associated morbidity as well as significant cost implications. The aim of this study is to evaluate features of the baseline ECG at LR implantation which might delineate increased propensity to paroxysmal atrial fibrillation. <h3>Methods</h3> We retrospectively studied a population of 192 adult patients who underwent LR implantation from January 2010 to March 2013 for the investigation of syncope or palpitations. LRs were checked every 3 months or whenever patients activated the LR. Information regarding demographics and co-morbidities were collected. Baseline ECG characteristics were collected at implant date. All the ECGs and EGMs were scrutinised by two blinded investigators. PAF incidence was defined as episodes lasting &gt;30 sec recorded in the LR memory. Multivariate logistic regression was used. <h3>Results</h3> Our LR population consists of 192 patients, 99 (52%) male, with a median age of 64 years (range 18–88), in whom LR was implanted for the investigation of syncope (65%), palpitations (17%) or both (18%). PAF was detected by LR in 39 patients. Median age of this group was 76 (range 38<b>–</b>88), 25 (65%) were male. 24 (62%) recorded a symptomatic event on the LR. Multivariate logistic regression analysis identified age (OR 1.05, 95% CI 1.01–1.08, p = 0.004), cigarette smoking (OR 3.82, 95% CI 1.45–10.02, p = 0.007) and RBBB (OR 6.57, 95% CI 2.23–19.36, p = 0.0007) as significant predictors of AF. The major finding was the increased prevalence of RBBB at baseline, detected in 15 (38%) of patients who went on to demonstrate PAF (5 complete and 10 incomplete RBBB). <h3>Conclusion</h3> In our study we looked at incidence and burden of paroxysmal episodes of AF in a loop recorder population. Predictive factors included advancing age, cigarette smoking and right bundle branch block. Incomplete right bundle branch block has already been postulated as a predictive factor for atrial fibrillation, and our study supports that hypothesis, using a larger sample population. Knowledge that these three factors may predispose to atrial fibrillation may be a useful guide when deciding whether to further investigate individuals to minimise thromboembolic risk and to develop an optimal anti-arrhythmic strategy.Future research should be directed toward identifying the relationship between RBBB and PAF.

Paroxysmal atrial fibrillation occurs often in cryptogenic ischaemic stroke. Final results from the SURPRISE study

Atrial fibrillation (AF) increases the risk of stroke fourfold and is associated with a poor clinical outcome. Despite work-up in compliance with guidelines, up to one-third of patients have cryptogenic stroke (CS). The prevalence of asymptomatic paroxysmal atrial fibrillation (PAF) in CS remains unknown. The SURPRISE project aimed at determining this rate using long-term cardiac monitoring. Patients with CS after protocolled work-up including electrocardiography (ECG) and telemetry were included after informed consent. An implantable loop recorder (ILR) was implanted subcutaneously. PAF was defined by events of atrial arrhythmia >2min with a correlating one-lead ECG confirming the diagnosis. Eighty-five patients were monitored for a mean of 569days (SD ±310). PAF was documented in 18 patients (20.7%) during the study period and detected by ILR in 14 patients (16.1%). In three patients PAF was detected by other methods before or after monitoring and was undiscovered due to device sensitivity in one case. The first event of PAF was documented at a mean of 109days (SD ±48) after stroke onset. PAF was asymptomatic in all cases and occurred in episodes lasting predominantly between 1 and 4h. Four recurrent strokes were observed, three in patients with PAF; all three patients were on oral anticoagulation (OAC). One in five patients with CS had PAF, which occurred at low burden and long after stroke. Future studies should determine the role of implantable cardiac monitors after stroke and determine the potential therapeutic benefit of OAC treatment of patients with PAF.

The Effects of Ranolazine on Paroxysmal Atrial Fibrillation in Patients with Coronary Artery Disease: A Preliminary Observational Study.

The impact of ranolazine, an anti-ishemic agent with antiarrhythmic properties, on paroxysmal atrial fibrillation (PAF) in patients with coronary artery disease (CAD) remains unclear. Pacing devices can be useful tools for disclosing even asymptomatic PAF. Purpose of this study is to assess the effect of ranolazine on atrial fibrillation (AF), in patients with CAD, PAF and a dual-chamber pacemaker. We studied 74 patients with CAD, PAF, and sick sinus syndrome or atrio-ventricular block, treated with pacemakers capable to detect PAF episodes. The total time in AF, AF burden, and the number of PAF episodes within the last 6 months before enrolment in the study, mean AF duration per episode, and the QTc interval were initially assessed. Subsequently, patients were randomized into additional treatment with ranolazine (375 mg twice daily) or placebo. Following six months of treatment, all parameters were reassessed and compared to those before treatment. Ranolazine was associated with shorter total AF duration (81.56±45.24 hours versus 68.71±34.84 hours, p=0.002), decreased AF burden (1.89±1.05% versus 1.59±0.81%, p=0.002), and shortened mean AF duration (1.15±0.41 hours versus 0.92±0.35 hours, p=0.01). In the placebo group no such differences were observed. In both groups, no significant differences in the number of PAF episodes and QTc duration were observed. We conclude that in patients with CAD and PAF, ranolazine reduces the total time in AF, AF burden, and mean AF duration. These findings may imply additional antiarrhythmic properties of ranolazine on atrial myocardium and might indicate the necessity of its use in ischemic patients with PAF.

Progression to the Persistent Form in Asymptomatic Paroxysmal Atrial Fibrillation

This study investigated the progression of paroxysmal atrial fibrillation (AF) to the persistent form in Japanese asymptomatic AF patients. Data were derived from a single hospital-based cohort in the Shinken Database 2004-2012 (n=19,994), in which 1,176 patients were diagnosed as having paroxysmal AF. AF progression occurred in 115 patients (6.0%/year) during the mean follow-up period (1,213±905 days). Although patients who were asymptomatic at the initial visit (n=468) had a low-risk profile compared with symptomatic patients, they had greater AF progression at follow-up (unadjusted hazard ratio, 1.611; 95% CI: 1.087-2.389; P=0.018). Absence of symptoms, male sex, and cardiomyopathy were independent predictors for AF progression in the multivariate model. It was noted that asymptomatic patients were less likely to undergo pulmonary vein isolation (PVI). In addition, the interaction term between asymptomatic AF and absence of PVI could be another independent predictor for AF progression. Prognosis was similar between asymptomatic and symptomatic patients with AF. Irrespective of low-risk profile, patients with asymptomatic paroxysmal AF had greater progression of AF compared with symptomatic patients. This paradoxical result appeared to be the result of less intensive clinical management, including invasive rhythm control.