Onset Of Paroxysmal Atrial Fibrillation Research Articles

The role of the TAPSE/PASP ratio in the prediction of paroxysmal atrial fibrillation in patients with acute ischemic stroke

Aims: Atrial fibrillation (AF) remains the most prevalent cause of cardioembolic stroke. Paroxysmal AF (PAF) is often difficult to be diagnosed and is sometimes first detected during embolic stroke. Yet, TAPSE and PASP can be easily revealed in routine transthoracic echocardiography (TTE). Then, the TAPSE/PASP ratio is often shown to have prognostic significance in many cardiac disorders. Nevertheless, the insufficient scholarly knowledge of the relationship between this ratio and the development of PAF became the primary motive of the present study.
 Methods: We carried out this study with 114 patients experiencing acute ischemic stroke without a previous diagnosis of AF. We noted down the patients’ blood parameters and prescribed drugs and calculated TAPSE/PASP ratio relying on their TTE findings. We also recorded the 24-hour heart rhythm findings of each patient through Holter monitoring. After categorizing PAF attacks (i.e.,PAF attack was (not) observed), we explored any statistical relationship between the TAPSE/PASP ratio and the presence of PAF.
 Results: The findings revealed a significant difference between the TAPSE/PASP ratios between the groups with PAF (0.62±0.07) and without PAF (0.77±0.08). Moreover, the receiver operating characteristic (ROC) curve analysis yielded the TAPSE/PASP ratio to demonstrate a diagnostic value in predicting PAF (area under the ROC curve [AUC]=0.89;82.7%; p

PS-R02-10: SYNCOPE ASSOCIATED WITH PAROXYSMAL ATRIAL FIBRILLATION AND ITS TREATMENT WITH CRYOABLATION

Aims: The main objective to present this case is creating awareness about syncope attacks and cryoablation procedure. Case report: A 60-year-old female patient was admitted to the cardiology department of Suleyman Demirel University Research and Education Hospital from an external center with the complaint of syncope attacks. The patient stated that she fainted with loss of consciousness while working. Patient was diagnosed before with hypertension and is being under treatment with 5 mg of ramipril (1x1). Patient was examined with echocardiography and electrocardiogram, after evaluating results, pathology was not founded. Ejection fraction (EF) %60, mitral regurgitation and tricuspid regurgitation were minimum, pulmonary artery pressure was 28 mmHg. For further examination, rhythm Holter and tension Holter were preferred. As results of tension holter, tension was regular and there was no hypotension. As results of rhythm holter, multiple paroxysmal atrial fibrillation attacks with the longest 5.3 pause was observed. Average heart rate was 55 beats per minute, for this reason beta blockers werent chosen as a treatment. Patient was recommend to undergo cryoablation procedure. Cryoablation procedure was performed with Medtronic The Arctic Front Advance through femoral vein. Afterwards, a transeptal passage was made from the right atrium to the left atrium with a Brockenbrough needle. Four pulmonary veins in order of left lower, left upper, right lower, right upper were isolated from extra focuses electrophysiologically without complication. The patient was called for monthly checkups and prescribed with edoksaban tosilat. After checkups, syncope attacks and palpitations were not founded. In three month checkup, the patient was examined with rhythm Holter, pause and paroxysmal atrial fibrillation were not observed. Results: Syncope is a sudden consciousness with a loss of postural tone which caused by pathologies. Epidemiology and prognosis of syncope is various in general population. Syncope can be caused by neurological diseases or cardiovascular problems. Since syncope attacks occur as a symptom of many diseases, they ought to be investigated gradually. Patients with syncope associated with paroxysmal atrial fibrillation are predisposed to an abnormal neural response during both sinus rhythm and arrhythmia. In some patients the onset of atrial fibrillation triggers vasovagal syncope. However, in our case, there were pauses due to atrial fibrillation with a slow ventricular response, and syncope probably developed due to this phenomenon. Therefore, ablation was a curative treatment in our patient. As a conclusion further studies are needed to figure out the relationship between syncope and cardivascular diseases.

The characteristics of pre-excitation syndrome concomitant with atrial tachyarrhythmia and the effect of radiofrequency ablation.

Wolff-Parkinson-White (WPW) concomitant with atrial tachyarrhythmia (ATA) has not been systemically characterized. Detailed electroanatomical mapping of the right atrium (RA) and/or left atrium (LA) was performed using three-dimensional mapping and the accessory pathway (AP) was mapped. WPW syndrome with ATA was diagnosed in 11 patients (median age 60 years). The characteristic of unidirectional anterograde conduction over the AP was displayed in nine patients, six of whom were intermittent. Sustained atrial tachycardia, that is, counterclockwise atrial flutter (AFL) with a median tachycardia cycle length (TCL) of 225 (220-275) ms, was mapped in eight patients; furthermore, "figure 8" right atrial reentry was mapped with TCL 250ms in one patient with a surgical history of ventricular septal defect repair. The remaining two patients underwent mitral annulus-dependent AT after paroxysmal atrial fibrillation (PAF) ablation and LA micro-reentry AT, respectively. In four patients, the location of the APs was left posterior. Left-lateral APs were identified in four patients. The locations of the APs in the remaining three patients were the right posterior and middle septum. All ATAs and APs were successfully ablated. After a median follow-up of 37 (15-72) months, no anterograde conduction over the AP was recorded, new onset of PAF was recorded in three patients, and all of them underwent circumferential pulmonary vein isolation. WPW with concomitant ATA frequently had continuous anterograde conduction over the AP with a rapid ventricular rate. Most WPWs displayed the characteristic of unidirectional anterograde conduction.

Association Between TCF21 Gene Polymorphism with the Incidence of Paroxysmal Atrial Fibrillation and the Efficacy of Radiofrequency Ablation for Patients with Paroxysmal Atrial Fibrillation.

PurposeAtrial fibrillation (AF) is the most common sustained arrhythmia with a high rate of recurrence after catheter ablation. The gene encoding transcription factor 21 (TCF21) has been linked to coronary artery disease risk by human genome-wide association studies in multiple racial ethnic groups. However, the association of TCF21 with AF remains unclear.Patients and MethodsCirculating leukocytes in patients with paroxysmal AF (PAF) and 92 age-matched controls without a history of cardiovascular disease, AF and other arrhythmias were collected. A total of 224 PAF patients receiving radiofrequency ablation had an 18-month scheduled follow-up study for recurrence of AF. Three single-nucleotide polymorphisms (SNPs) of TCF21 (rs2327429, rs2327433 and rs12190287) were genotyped by PCR, and serum levels of TCF21 were measured by ELISA.ResultsMore males and smokers were observed in the PAF group compared with controls. C allele of rs2327429, G allele and GG genotype of rs12190287 were markedly associated with the increased onset of PAF. The levels of serum TCF21 were significantly higher in PAF group than those in control group (1.96 ± 0.85 vs 0.86 ± 0.49 ng/mL, P<0.001). Based on logistic regression analysis, we confirmed that risk allele at rs12190287 and serum TCF21 concentration were independently correlated with the incidence of PAF. Furthermore, GG genotype of rs12190287 enhanced the susceptibility of AF recurrence after ablation.ConclusionG allele and GG genotype of rs12190287 in TCF21 and elevated TCF21 concentration are significantly associated with the onset of PAF and recurrence after ablation.

Sleep apnea and atrial fibrillation: the spell of Groundhog Day.

Sleep apnea and atrial fibrillation: the spell of Groundhog Day.

Scanning of paroxysmal atrial fibrillation as an etiological risk factor in patients with acute ischemic stroke: prospective study.

Prevention of recurrence of stroke depends on recognition of the underlying mechanism of ischemia. To screen patients who were hospitalized with diagnosis of acute ischemic stroke in terms of atrial fibrillation (AF) with repeated Holter electrocardiography recordings. Prospective study conducted at Konya Education and Research Hospital, Turkey. Patients with a diagnosis of acute ischemic stroke, without atrial fibrillation on electrocardiography (ECG), were evaluated. Their age, gender, histories of previous ischemic attack, occurrences of paroxysmal atrial fibrillation (PAF) and other risks were assessed during the first week after acute ischemic stroke and one month thereafter. ECG recordings were obtained from 130 patients through 24-hour ambulatory Holter. Patients without PAF attack during the first Holter were re-evaluated. PAF was detected through the first Holter in 33 (25.4%) out of 130 acute ischemic stroke patients. A second Holter was planned for 97 patients: 53 (54.6%) of them could not attend due to COVID-19 pandemic; while 44 (45.3%) patients had the second Holter and, among these, 4 (9.1%) had PAF. The only parameter associated with PAF was older age. Four (10.8%) of the 37 patients with PAF had also symptomatic carotid stenosis. Detecting the presence of PAF by screening patients with no AF in the ECG through Holter ECG examinations is valuable in terms of changing the course of the treatment. It should be kept in mind that the possibility of accompanying PAF cannot be ruled out in the presence of other factors that pose a risk of stroke.

Obstructive sleep apnea and nocturnal attacks of paroxysmal atrial fibrillation.

Obstructive sleep apnea (OSA) is commonly seen in patients with atrial fibrillation (AF), but it is unclear to what extent this relationship is one of causation or association. We examined a cohort of patients with paroxysmal AF to determine whether the presence of OSA (apnea-hypopnea index ≥ 15 events/h) affects the time of onset of symptomatic AF episodes. Patients with a recent emergency department visit for a symptomatic episode of paroxysmal AF were recruited from an AF clinic. The time of onset of the AF attack was classified as occurring in "sleeping hours" or "waking hours" based on direct history from the patient and emergency department visit documentation. Of 152 patients with paroxysmal AF, 67 underwent polysomnography; 1 (1.5%) had central sleep apnea, 46 (68.7%) had mild or no OSA, and 20 (29.8%) had OSA. In the OSA group, 14/20 (70.0%) had their symptomatic AF attack during sleeping hours compared to 12/46 (26.1%) in the mild or no OSA group (P = .001). Compared with those who had a paroxysmal AF attack during waking hours, and adjusting for confounders, those who had a paroxysmal AF attack during sleeping hours had almost 6 times the odds of having OSA (odds ratio, 5.53; P = .007). Compared to patients with paroxysmal AF with mild or no OSA, those with OSA were far more likely to have a symptomatic AF attack during sleeping hours, supporting a causal role for OSA in the pathogenesis of AF in this population. These findings strongly suggest that patients who have nocturnal AF attacks should be evaluated for OSA. Lin C-H, Timofeeva M, O'Brien T, Lyons OD. Obstructive sleep apnea and nocturnal attacks of paroxysmal atrial fibrillation. J Clin Sleep Med. 2022;18(5):1279-1286.

Autonomic Tone Variations Prior to Onset of Paroxysmal Atrial Fibrillation.

BackgroundVariations of heart rate variability (HRV) before paroxysmal atrial fibrillation (PAF) onset are still controversial. We aimed to observe the autonomic tone variations before PAF onset based on HRV analysis.Material/MethodsWe prospectively investigated 24-h Holter recordings of 60 patients with PAF (M/F: 34/26) and 40 healthy people in sinus rhythm (M/F: 18/12). According to clinical information and Poincaré scatter plot, 60 PAF patients were divided into sympathetic group (n=20) and vagus group (n=40). Time domain and frequency domain parameters of HRV were respectively measured before PAF episodes in 3 subgroups. Five time periods were studied using the ANOVA.ResultsNo significant variations were observed for the HRV parameters during 60 minutes preceding PAF in sympathetic group. A significant and linear change in SDNN, RMSSD, PNN50, HF and LF/HF during 60 minutes preceding PAF onset in vagus group. Compared with controls, RMSSD, LF and HF were significantly longer in patients with PAF during 60 minutes before PAF. Comparing sympathetic group and vagus group, we observed the same pattern of autonomic variations with a progressive decrease in LF and HF. A progressive decrease in PNN50 and LF/HF of sympathetic group and a significant increase in PNN50 and LF/HF of vagus group were also observed.ConclusionsPatients with PAF mediated by different autonomic nerves have HRV variations, especially vagus PAF, there was a progressive increase with vagal tone during 60 minutes before PAF onset. The findings may help clinicians better intervene in PAF.

Convolutional neural networks predict the onset of paroxysmal atrial fibrillation: Theory and applications.

In this study, we aimed to detect paroxysmal atrial fibrillation episodes before they occur so that patients can take precautions before putting their and others' lives in potentially life-threatening danger. We used the atrial fibrillation prediction database, open data from PhysioNet, and assembled our process based on convolutional neural networks. Conventional heart rate variability features are calculated from time-domain measures, frequency-domain measures using power spectral density estimations, time-frequency-domain measures using wavelet transform, and nonlinear Poincaré plot measures. In addition, we also applied an alternative heart rate normalization, which gave promising results only in a few studies, before calculating these heart rate variability features. We used these features directly and their normalized versions using min-max normalization and z-score normalization methods. Thus, heart rate variability features extracted from six different combinations of these normalizations, in addition to no normalization cases, were applied to the convolutional neural network classifier. We tuned the classifiers' hyperparameters using 90% of feature sets and tested the classifiers' performances using 10% of feature sets. The proposed approach resulted in 87.76% accuracy, 91.30% precision, 80.04% recall, and 87.50% f1-score in heart rate variability with z-score feature normalization. When the heart rate normalization was also utilized, the suggested method gave 100% accuracy, 100% precision, 100% recall, and 100% f1-score in heart rate variability with z-score feature normalization. The proposed method with heart rate normalization and z-score normalization methods resulted in better classification performance than similar studies in the literature. By comparing the existing studies, we conclude that our approach provides a much better tool to determine a near-future paroxysmal atrial fibrillation episode. However, although the achieved benchmarks are impressive, we note that the approach needs to be supported by other studies and on other datasets before clinical trials.

Self-Reported Onset of Paroxysmal Atrial Fibrillation Is Related to Sleeping Body Position.

Background: Because stretch of the atrial myocardium is proarrhythmic for atrial fibrillation (AF) and a left lateral body position increases atrial dimensions in humans, we hypothesized that left lateral recumbence is a frequent AF-triggering body position in AF patients.Methods: We performed a questionnaire study of symptomatic paroxysmal AF (episodes of AF < 1 week) patients scheduled for a first AF ablation therapy at Catharina Hospital, Eindhoven, the Netherlands and at University Hospital, Bordeaux, France.Results: Ninety-four symptomatic paroxysmal AF patients were included [mean age 61 ± 11 years, median AF history of 29(48) months, 31% were females]. Twenty-two percent of patients reported a specific body position as a trigger of their AF symptoms. The triggering body position was left lateral position in 57% of cases, supine position in 33%, right lateral position in 10%, and prone position in 5% (p = 0.003 overall difference in prevalence). Patients with positional AF had a higher body mass index compared to patients without nocturnal/positional AF [28.7(4.2) and 25.4(5.2) kg/m2, respectively, p = 0.025], but otherwise resembled these patients.Conclusion: Body position, and the left lateral position, in particular, is a common trigger of AF in symptomatic AF patients. Moreover, positional AF is associated with overweight. Understanding of the underlying mechanisms of positional AF can contribute to AF treatment and prevention.

Probabilistic domain-knowledge modeling of disorder pathogenesis for dynamics forecasting of acute onset

Disease pathogenesis, a type of domain knowledge about biological mechanisms leading to diseases, has not been adequately encoded in machine-learning-based medical diagnostic models because of the inter-patient variabilities and complex dependencies of the underlying pathogenetic mechanisms. We propose 1) a novel pathogenesis probabilistic graphical model (PPGM) to quantify the dynamics underpinning patient-specific data and pathogenetic domain knowledge, 2) a Bayesian-based inference paradigm to answer the medical queries and forecast acute onsets. The PPGM model consists of two components: a Bayesian network of patient attributes and a temporal model of pathogenetic mechanisms. The model structure was reconstructed from expert knowledge elicitation, and its parameters were estimated using Variational Expectation-Maximization algorithms. We benchmarked our model with two well-established hidden Markov models (HMMs) – Input-output HMM (IO-HMM) and Switching Auto-Regressive HMM (SAR-HMM) – to evaluate the computational costs, forecasting performance, and execution time. Two case studies on Obstructive Sleep Apnea (OSA) and Paroxysmal Atrial Fibrillation (PAF) were used to validate the model. While the performance of the parameter learning step was equivalent to those of IO-HMM and SAR-HMM models, our model forecasting ability was outperforming those two models. The merits of the PPGM model are its representation capability to capture the dynamics of pathogenesis and perform medical inferences and its interpretability for physicians. The model has been used to perform medical queries and forecast the acute onset of OSA and PAF. Additional applications of the model include prognostic healthcare and preventive personalized treatments.

Cardiac Autonomic Dysfunction and Incidence of de novo Atrial Fibrillation: Heart Rate Variability vs. Heart Rate Complexity.

BackgroundThe REACT DX registry evaluates standard therapies to episodes of long-lasting atrial tachyarrhythmias and assesses the quality of sensing and stability of the lead and the implantable cardioverter-defibrillator (ICD) (BIOTRONIK Lumax VR-T DX and successors) over at least a 1-year follow-up period.ObjectiveTo study the association between the risk of de novo device-detected atrial fibrillation (AF), the autonomic perturbations before the onset of paroxysmal AF and a 7-days heart rate variability (7dHRV) 1 month after ICD implantation.MethodsThe registry consists of 234 patients implanted with an ICD, including 10 with de novo long-lasting atrial tachyarrhythmias with no prior history of AF. The patients were matched via the propensity-score methodology as well as for properties directly influencing the ECGs recorded using GE CardioMem CM 3000. Heart rate variability (HRV) analysis was performed using standard parameters from time- and frequency-domains, and from non-linear dynamics.ResultsNo linear HRV was associated with an increased risk of AF (p = n.s.). The only significant approach was derived from symbolic dynamics with the parameter “forbidden words” which distinguished both groups on all 7 days of measurements (p < 0.05), thereby quantifying the heart rate complexity (HRC) as drastically lower in the de novo AF group.ConclusionCardiac autonomic dysfunction denoted by low HRC may be associated with higher AF incidence. For patients with mild to moderate heart failure, standard HRV parameters are not appropriate to quantify cardiac autonomic perturbations before the onset of AF. Further studies are needed to determine the individual risk for AF that would enable interventions to restore autonomic balance in the general population.

Detection algorithm of paroxysmal atrial fibrillation with sparse coding based on Riemannian manifold

In order to solve the problem that the early onset of paroxysmal atrial fibrillation is very short and difficult to detect, a detection algorithm based on sparse coding of Riemannian manifolds is proposed. The proposed method takes into account that the nonlinear manifold geometry is closer to the real feature space structure, and the computational covariance matrix is used to characterize the heart rate variability (RR interval variation), so that the data is in the Riemannian manifold space. Sparse coding is applied to the manifold, and each covariance matrix is represented as a sparse linear combination of Riemann dictionary atoms. The sparse reconstruction loss is defined by the affine invariant Riemannian metric, and the Riemann dictionary is learned by iterative method. Compared with the existing methods, this method used shorter heart rate variability signal, the calculation was simple and had no dependence on the parameters, and the better prediction accuracy was obtained. The final classification on MIT-BIH AF database resulted in a sensitivity of 99.34%, a specificity of 95.41% and an accuracy of 97.45%. At the same time, a specificity of 95.18% was realized in MIT-BIH NSR database. The high precision paroxysmal atrial fibrillation detection algorithm proposed in this paper has a potential application prospect in the long-term monitoring of wearable devices.

Autonomic modulation before and after paroxysmal atrial fibrillation events in patients with ischemic heart disease.

The autonomic activity plays a critical role in generating paroxysmal atrial fibrillation (PAF). This study aimed to evaluate the changes in the autonomic nerve activity before and after PAF events in patients with and without ischemic heart disease (IHD). The study included 49 patients (71.43±12.24years old, 26 males) with PAF events lasting more than 30s during 24-hr ambulatory Holter monitoring. The 20-min intervals before and after PAF events were divided into eight segments of 5min each. Heart rate variability (HRV) analyses of the time and frequency domains were applied to each time segment. Patients with IHD had significant increases in the root mean square successive differences (r-MSSD, p=.008) and HF component (p=.04), followed by a significant increase in the LF/HF ratio (p=.02) preceding the onset of PAF. Patients without IHD had only a significant increase in the r-MSSD (p=.045) preceding the onset of PAF. During the termination of PAF events, patients in both the IHD and control groups had a significantly decreased r-MSSD and HF, respectively. Ischemic heart disease causes a sympathovagal imbalance in the initiation of PAF. Decreased parasympathetic activity regulated the termination of PAF in both the IHD and control groups. The modification of the autonomic nervous system (ANS) activity should be individualized due to the autonomic complexity in AF arrhythmogenesis and termination.

Flickering of cardiac state before the onset and termination of atrial fibrillation.

Complex dynamical systems can shift abruptly from a stable state to an alternative stable state at a tipping point. Before the critical transition, the system either slows down in its recovery rate or flickers between the basins of attraction of the alternative stable states. Whether the heart critically slows down or flickers before it transitions into and out of paroxysmal atrial fibrillation (PAF) is still an open question. To address this issue, we propose a novel definition of cardiac states based on beat-to-beat (RR) interval fluctuations derived from electrocardiogram data. Our results show the cardiac state flickers before PAF onset and termination. Prior to onset, flickering is due to a "tug-of-war" between the sinus node (the natural pacemaker) and atrial ectopic focus/foci (abnormal pacemakers), or the pacing by the latter interspersed among the pacing by the former. It may also be due to an abnormal autonomic modulation of the sinus node. This abnormal modulation may be the sole cause of flickering prior to termination since atrial ectopic beats are absent. Flickering of the cardiac state could potentially be used as part of an early warning or screening system for PAF and guide the development of new methods to prevent or terminate PAF. The method we have developed to define system states and use them to detect flickering can be adapted to study critical transition in other complex systems.

Comparison of apolipoprotein-A1 levels between paroxysmal atrial fibrillation patients and healthy subjects.

Introduction: Studies found that the inflammation plays a key role in the pathogenesis of paroxysmal atrial fibrillation (PAF). It is well-known that apolipoprotein-A1 (Apo-A1) demonstrates antiinflammatory and anti-oxidant properties in a healthy physiological system. In the present study, we aimed to determine whether there is any difference of Apo-A1 levels in patients with PAF and healthy subjects. Methods: In this prospective cohort study, we enrolled a total of 35 PAF patients and 34 comparable healthy participants. Apo-A1 levels were measured from each subject using an immunophelometric method. All enrolled subjects were followed-up for one year during the study period. Results: Serum high-sensitivity C-reactive protein (hs-CRP) levels were statistically higher in PAF patients compared to healthy subjects (1.54±1.99 vs. 1.06±2.01, P = 0.016, respectively). Of note, patients with PAF had lower Apo-A1 levels (1.84±0.74 vs. 2.55±0.44, P = 0.001, respectively). There was no statistical difference between the groups in terms of apolipoprotein-B levels (1.08±0.36 vs. 0.99±0.38, P = 0.339, respectively). We did not find any correlation between Apo-A1 levels and PAF attacks in the study. Conclusion: The main finding of this study was that Apo-A1 levels were significantly lower in PAF patients compared to healthy participants. Based on our results, we considered that Apo-A1 may have a key role in the pathogenesis of PAF.

Huge Hiatal Hernia Mimicking a Mass with Compressive Effects on the Left Atrium Causing Paroxysmal Atrial Fibrillation

An 82-year-old female patient presented with complaints of dyspnea and increasing palpitations caused by food reflux. There was no risk factor except hypertension. On physical examination, the heart rate was 120 beats/min and arrhythmic and blood pressure was 130/80 mmHg. Electrocardiography showed high-rate atrial fibrillation. Laboratory parameters were unremarkable. Echocardiography illustrated a hyperechogenic and well-circumscribed mass, 40×55 mm size, in the posterior left atrium (Figure 1, Video 1). The mass size increased with breathing and the Valsalva maneuver. There was no pathology on chest radiography. The atrial fibrillation returned to sinus rhythm spontaneously, but paroxysmal atrial fibrillation attacks were observed, which were related to food reflux at follow-up. Subsequently, cardiac computed tomography, performed to determine the etiology, failed to demonstrate any pathological findings involving the left atrium. However, there was a sliding hernia in the paraesophageal region compressing the left atrium from the inferior-posterior region (Figure 2). Hiatal hernia surgery was recommended on account of the intermittently repeating symptoms. The patient refused the operation, and she is under follow-up with medical treatment.

Prediction of PAF Attacks using Time-Domain Measures of Heart Rate Variability

Paroxysmal atrial fibrillation (PAF) is the mainly encountered type of arrhythmia and there is no validated method to predict a PAF attack before it occurs. In this study, predicting the PAF event was aimed using time-domain heart rate variability (HRV) measures in k- nearest neighbor (k-nn) classifier. Traditional time-domain HRV measures were analyzed in every 5-minute segments from 49 normal subjects, 25 patients with PAF attack and 25 patients with no attack within 45 minutes. All features were investigated whether they showed statistically significance. Significant features were classified by k-nn for odd numbers of neighbors between 1 and 19. This setup was run with two different configurations as study 1 to discriminate patients with PAF attack from normals and patients with no attack, and study 2 to discriminate patients with PAF attack from patients with no attack. SDNN, RMSSD and pNN50 measures were found to show statistically significant differences with p less than 0.05 in segments of 0-5 min, 2.5-7.5 min and 5-10 min intervals only. The maximum classification accuracy was obtained in the time interval of 2.5-7.5 minutes with %79 for Study 1 and just before attack with %80 for Study 2 in the time interval of 0-5 minutes. Results showed that the prediction of PAF events was possible when the classification between normal subjects from PAF patients was accurate. PAF attack can be determined 2.5 minutes earlier by simple classifier algorithms.

EP11 DOES TYPE OF CARDIOPLEGIA AFFECT THE INCIDENCE OF POSTOPERATIVE PAROXYSMAL ATRIAL FIBRILLATION IN PATIENTS UNDERGOING CARDIAC SURGERY?

Abstract Background and Aim: Paroxysmal atrial fibrillation (PAF) is the most frequent complication following cardiac surgery. Despite high incidence, its etiology remains uncler. Aim of our investigation was to analyze retrospectively the pathogenetic role of different types of cardioplegia on the onset of PAF. Methods: Sixty-hundred and sixty patients underwent on-pump cardiac surgery between January 2015 and October 2016. Redo operations and emergency surgery were excluded. The types of cardiolplegic solution administered were warm blood cardioplegia (Calafiore, n = 480), cold crystalloid extracellular cardioplegia (St. Thomas, n = 71), cold crystalloid intracellular cardioplegia (Custodiol, n = 109). The way of admistation was antegrade for all types of cardioplegic solution. Results: The incidence of postoperative PAF was 36.2% (239 patients). Two-hundred patients were initially treated by mens of amiodarone infusion that successfully allowed cardioversion in 167 cases (83.5%); in the other 39 patients were initially administered other drugs (i.e. verapamil e.v./per os, beta-blokers per os). A relation between the type of cardioplegic solution and the onset of postoperative PAF was not found (Calafiore, n = 180, 37.5%; St. Thomas, n = 22, 31%; Custodiol, n = 37, 34%; p = NS). Advanced age at operation (71.3 ± 8.7 vs. 65.7 ± 11 years) was the only independent predictor of PAF (p &lt; 0.001). Non-coronary surgery was found as risk factor for PAF at the univariate analysis only (p &lt; 0.01). Conclusions: The use of different type of cardioplegic solutions, and at different temperatures, does not correlate with the onset of postoperative PAF. Initial treatment strategy with amiodarone infusion allows pharmacological cardioversion of PAF in over 80% of cases.

5046The significance of early new onset of paroxysmal atrial fibrillation during acute myocardial infarction

5046The significance of early new onset of paroxysmal atrial fibrillation during acute myocardial infarction