Different Types Of Atrial Fibrillation Research Articles

The role of the right atrial appendage and right atrium in post-radiofrequency ablation recurrence in different types of atrial fibrillation

To quantitatively evaluate the relationship between the anatomical parameters of the right atrium and the recurrence of atrial fibrillation (AF) after radiofrequency ablation, considering different types of AF, utilizing 256-slice spiral computed tomography (CT). A total of 297 patients with AF who underwent initial radiofrequency ablation were enrolled, divided into the paroxysmal atrial fibrillation (PaAF) group (n=230) and the persistent atrial fibrillation (PeAF) group (n=67). Subsequently, patients in each group were further stratified into recurrent and non-recurrent subgroups. In addition, 100 healthy outpatients were selected as the normal group. All patients underwent preoperative cardiac CT (CCT) examination. The volumes of the right atrium (RA), right atrial appendage (RAA), and left atrial (LA), RAA height, the length, short diameter, perimeter, and area of the RAA base, anteroposterior diameter of the RA, tricuspid annulus diameter, crista terminalis, and inferior vena cavotricuspid isthmus (CTI) on CCT images were measured. In both the PaAF group and the PeAF group, except for the crista terminalis thickness, the other measured parameters were greater than those in the normal group, and recurrent patients exhibited larger RAA base, crista terminalis and LA volume. Recurrent patients with PeAF presented larger RAVI, while recurrent patients with PaAF did not. The short diameter of the RAA base was an independent predictor of recurrence in patients with PaAF (p=0.001), while the height of the RAA, thickness of the crista terminalis, and hypertension were independent predictors of recurrence in PeAF (p<0.05). The ROC curve was used to analysis the predictive model in PaAF and PeAF group, the corresponding sensitivity and specificity were 0.604 and 0.864 in PaAF group, respectively (AUC=0.840, P=0.001), in PeAF group, the corresponding sensitivity and specificity were 0.967 and 0.892, respectively (AUC=0.959, P=0.001). The short diameter of RAA base > 22.15 mm had the highest predictive value for recurrence in PaAF patients, with a sensitivity of 0.887, and a specificity of 0.520 (AUC: 0.743, p=0.001). The RAA height > 28.95 mm has the highest predictive value for recurrence in PeAF, with a sensitivity of 0.633, and a specificity of 0.865 (AUC: 0.816, p=0.001). Recurrent patients both in the PaAF and PeAF groups demonstrated larger RAA base and RA structural parameters. Compared to patients with PaAF, recurrent patients with PeAF presented larger RA volume.

Effect of catheter ablation versus medical therapy on mental health and quality of life in patients with atrial fibrillation: a systematic review and meta-analysis of randomized controlled trials.

The association between atrial fibrillation (AF) and mental health is well-documented, but the relative benefits of catheter ablation versus medical therapy on mental health and quality of life are not clearly understood. This study assesses the impact of these interventions on AF patients' mental health and quality of life. Through a systematic review of PubMed, Scopus, and Cochrane databases, randomized controlled trials (RCTs) comparing catheter ablation to medical therapy for AF were analyzed. The study focused on a range of outcomes, particularly mental health and quality of life, measured by tools including the SF-36 mental component, HADS, SF-36 physical component, and AFEQT scores, among others. Analyses were stratified by AF type (paroxysmal versus persistent) and synthesized using random or fixed-effects models to calculate mean differences (MDs) or standardized mean differences (SMDs) with 95% confidence intervals (CIs). From 24 RCTs totaling 6,353 patients (51.4% receiving catheter ablation, 71.1% male, average age 59), catheter ablation was found to significantly improve mental health (SMD 0.34; 95% CI 0.05-0.63; p = 0.02) and quality of life as indicated by PCS SF-36 (MD 2.64; 95% CI 1.06-4.26; p < 0.01) and AFEQT scores (MD 6.24; 95% CI 4.43-8.05; p < 0.01), with no significant difference in outcomes between AF subtypes. Catheter ablation offers significant improvements in mental health and quality of life over medical therapy for AF patients, demonstrating its efficacy across different types of AF.

Machine learning-based atrial fibrillation detection and onset prediction using QT-dynamicity

Objective. This study examines the value of ventricular repolarization using QT dynamicity for two different types of atrial fibrillation (AF) prediction. Approach. We studied the importance of QT-dynamicity (1) in the detection and (2) the onset prediction (i.e. forecasting) of paroxysmal AF episodes using gradient-boosted decision trees (GBDT), an interpretable machine learning technique. We labeled 176 paroxysmal AF onsets from 88 patients in our unselected Holter recordings database containing paroxysmal AF episodes. Raw ECG signals were delineated using a wavelet-based signal processing technique. A total of 44 ECG features related to interval and wave durations and amplitude were selected and the GBDT model was trained with a Bayesian hyperparameters selection for various windows. The dataset was split into two parts at the patient level, meaning that the recordings from each patient were only present in either the train or test set, but not both. We used 80% on the database for the training and the remaining 20% for the test of the trained model. The model was evaluated using 5-fold cross-validation. Main results. The mean age of the patients was 75.9 ± 11.9 (range 50–99), the number of episodes per patient was 2.3 ± 2.2 (range 1–11), and CHA2DS2-VASc score was 2.9 ± 1.7 (range 1–9). For the detection of AF, we obtained an area under the receiver operating curve (AUROC) of 0.99 (CI 95% 0.98–0.99) and an accuracy of 95% using a 30 s window. Features related to RR intervals were the most influential, followed by those on QT intervals. For the AF onset forecast, we obtained an AUROC of 0.739 (0.712–0.766) and an accuracy of 74% using a 120s window. R wave amplitude and QT dynamicity as assessed by Spearman’s correlation of the QT-RR slope were the best predictors. Significance. The QT dynamicity can be used to accurately predict the onset of AF episodes. Ventricular repolarization, as assessed by QT dynamicity, adds information that allows for better short time prediction of AF onset, compared to relying only on RR intervals and heart rate variability. Communication between the ventricles and atria is mediated by the autonomic nervous system (ANS). The variations in intraventricular conduction and ventricular repolarization changes resulting from the influence of the ANS play a role in the initiation of AF.

Clinical outcomes of radiofrequency catheter ablation guided by intracardiac echocardiography for Chinese atrial fibrillation patients: a single-center, retrospective study.

Intracardiac echocardiography (ICE) is a novel technology with certain advantages in treatment of atrial fibrillation (AF), yet there is limited research on the use of ICE in radiofrequency ablation for AF treatment in China. The aim of this study was to investigate the total fluoroscopy time and dose, safety, and effectiveness of ICE guided vs. traditional fluoroscopy (non-ICE) guided radiofrequency ablation for AF in China. We conducted a single-center retrospective analysis of patients who underwent ICE or traditional fluoroscopy-guided radiofrequency ablation for AF. The primary endpoint of this study was total fluoroscopy time, and the secondary endpoints included total fluoroscopy dose, acute surgery failure, transseptal puncture time, ablation time, total procedure time, and 6-month surgery success (no AF recurrence or atrial flutter). As an exploratory analysis, outcomes of interest by different types of AF were examined. A total of 97 patients were included in the analysis. Forty-eight were in the ICE group and 49 were in the non-ICE group with comparable demographic and clinical characteristics at the baseline. None of patients experienced acute surgery failure with no major procedure-related complications occurred. The fluoroscopic time and dose were significantly lower in the ICE group compared to the non-ICE group (0.00 vs. 9.67±4.88 min, P<0.001; 0.00 vs. 77.10±44.28 mGy/cm2, P<0.001, respectively). There were no statistically significant differences in transseptal puncture time, ablation time and total procedure time between the two groups. There were two AF recurrences observed during the 6-month follow-up in each group (P>0.99). ICE significantly reduced the fluoroscopic time and dose for radiofrequency catheter ablation in AF patients. There were no significant differences in safety or effectiveness outcomes between the ICE and non-ICE groups.

Quantitative assessment of left ventricular myocardial work in patients with different types of atrial fibrillation by non-invasive pressure-strain loop technique.

This study aimed to analyze myocardial work in patients with atrial fibrillation (AF) using a noninvasive pressure strain loop (PSL) technique to provide a basis for the quantitative assessment of left ventricular (LV) systolic function. LV myocardial work of 107 AF patients (56 with paroxysmal atrial fibrillation and 51 with persistent atrial fibrillation) and 55 healthy individuals were assessed by the noninvasive PSL and then compared. Global longitudinal strain (GLS) in absolute values, global work index (GWI), global constructive work (GCW), and global work efficiency (GWE) were significantly lower in the AF group than control group, whereas peak strain dispersion (PSD) and global wasted work (GWW) were significantly higher (P<.05). Further subdivision according to the AF type revealed that, compared with the controls, GLS in absolute values and GWE decreased significantly; PSD and GWW increased significantly in the paroxysmal AF group (P<.05). Nevertheless, GWI and GCW were not significantly different between paroxysmal AF and control groups (P>.05). Compared to paroxysmal AF, persistent AF induced a further decrease in absolute GLS and GWE and a further increase in GWW (P<.05), but PSD did not increase further (P>.05). Multiple linear regression analysis showed that GWI and GCW were independently associated with systolic blood pressure. GWW was associated with types of AF and left atrial volume index (LAVI). GWE was correlated with age, types of AF, disease duration, and LAVI. Receiver operating characteristic curve analysis showed that the area under the curve predicting myocardial injury was higher for GWE and GWW than for GLS (area under the curve: .880, .846, and .821, respectively). Non-invasive PSL can quantitatively assess LV systolic function in patients with different kinds of AF and detect early subclinical myocardial injury in patients with paroxysmal AF. GWE and GWW outperform GLS and LV ejection fraction when assessing myocardial injury. Systolic blood pressure, type of AF, LVAI, disease duration, and age may be associated with myocardial injury in patients with AF.

Characterization of retinal microvasculature and structure in atrial fibrillation.

Quantitative changes in retinal microvasculature are associated with subclinical cardiac alterations and clinical cardiovascular diseases (i.e., heart failure and coronary artery disease). Nonetheless, very little is known about the retinal vascular and structural changes in patients with atrial fibrillation (AF). Our study aims to characterize the microvasculature and structure of the retina in AF patients and explore their differences in different types of AF (paroxysmal and sustained AF). This cross-sectional study was conducted at the Departments of Neurology and Cardiology in West China Hospital, Chengdu, China. Individuals aged 40 years or older with a diagnosis of AF were eligible for inclusion and underwent an evaluation and diagnosis confirmation before enrollment. Control individuals aged 40 years or older and without a history of AF, ocular abnormalities/disease, or any significant systemic illness were recruited. The retinal vascular and structural parameters were assessed using swept-source optical coherence tomography (SS-OCT)/SS-OCT angiography. Echocardiographic data of left atrium (LA) diameter were collected in patients with AF at the time of inclusion. A total of 242 eyes of 125 participants [71 men (56.8%); mean (SD) age, 61.98 (8.73) years] with AF and 219 eyes of 111 control participants [53 men (47.7%); mean (SD) age, 62.31 (6.47) years] were analyzed. In our AF cohort, 71 patients with paroxysmal AF and 54 patients with sustained AF (i.e., persistent/permanent AF) were included. Decreased retinal microvascular perfusion (β coefficient = -0.08; 95% CI, -0.14 to -0.03) and densities (β coefficient = -1.86; 95% CI, -3.11 to -0.60) in superficial vascular plexus (SVC) were found in the eyes of the participants with AF. In regard to retinal structures, thinner ganglion cell-inner plexiform layer (GCIPL; β coefficient = -2.34; 95% CI, -4.32 to -0.36) and retinal nerve fiber layer (RNFL) thicknesses (β coefficient = -0.63; 95% CI, -2.09 to -0.18) were observed in the eyes of the participants with AF. The retinal parameters did not significantly differ between paroxysmal and sustained AF (all P > 0.05). However, significant interactions were observed between LA diameter and AF subtypes with the perfusion and densities in SVC (P < 0.05). This study found that individuals with AF had decreased retinal vascular densities and perfusion in SVC, as well as thinner GCIPL and RNFL thickness compared with age- and sex-matched control participants. The differences of the retinal microvasculature in SVC between paroxysmal and sustained AF depend on the LA diameter. Given our findings, further longitudinal studies with our participants are of interest to investigate the natural history of retinal microvascular and structural changes in individuals across the clinical process of AF and AF subtypes.

An Observational Study: Clinical Manifestations and Prognosis of Left Atrial Thrombosis in Atrial Fibrillation.

We did this study to find out the clinical manifestations and prognosis of left atrial thrombosis in different types of atrial fibrillation and the relationship with systemic thromboembolism, hoping to find a better therapy strategy. A single-center retrospective study enrolled patients with definite diagnosis of atrial fibrillation complicated with left atrial thrombosis. Data of general clinical information, anticoagulation medications, thromboembolism events, and thrombosis prognosis were recorded and analyzed. A total of 103 patients were enrolled. Compared with non-valvular atrial fibrillation (NVAF), thrombosis outside the left atrial appendage (LAA) was much more common in valvular atrial fibrillation (VAF) with p=0.003. Total prevalence of systemic thromboembolism was 33.0%. Thrombi disappeared in 78 cases (75.7%) under anticoagulation treatment within 2 years. There was no significant difference between warfarin, dabigatran, and rivaroxaban on thromboembolism events and thrombosis prognosis in NVAF, with p=0.740 and 0.493, respectively. Atrial fibrillation patients with LA thrombosis have a high risk of systemic thromboembolism events. Compared with NVAF, patients with VAF had higher incidence of thrombosis outside the LAA. Standard stroke-preventing doses of anticoagulants might not be sufficient to deplete all LA thrombi. There was no statistically difference between warfarin, dabigatran, and rivaroxaban for depleting LA thrombi in NVAF patients.

The predictive value of left atrium epicardial adipose tissue on recurrence after catheter ablation in patients with different types of atrial fibrillation

BackgroundA growing body of evidence supports that the left atrium epicardial adipose tissue (LA-EAT) is related to the occurrence and recurrence of atrial fibrillation (AF). The relationship between LA-EAT and the recurrence after radiofrequency catheter ablation (RFCA) in patients with different types of AF is still unclear. This study aims to evaluate the predictive value of LA-EAT on the recurrence of AF after RFCA in patients with different types of AF. Methods301 AF patients who underwent RFCA for the first time were divided into the paroxysmal atrial fibrillation (PAF) group (n = 181) and the persistent atrial fibrillation (PersAF) group(n = 120), which were followed up at 3, 6, and 12 months. All patients underwent left atrial computed tomography angiography (CTA) examination before the operation, and LA-EAT was measured using software (Advantage Workstation4.6, GE, USA). ResultsAfter a median follow-up of 10.7 months, 73/301 patients (24.25%) had a recurrence of AF, including 43 /120(35.83%) patients with PersAF and 30/181(16.57%) patients with PAF. In multivariable Cox regression analysis, LA-EAT volume (OR = 1.053;95%CI: 1.024–1.083, p < 0.001), attenuation (OR = 0.949;95%CI:0.911–0.988, p = 0.012) and left atrial diameter (LAD) (OR = 1.063;95%CI:1.002–1.127，p = 0.043) were independent risk factors for recurrence in patients with PersAF but not in patients with PAF. ConclusionLA-EAT volume and attenuation are independent risk factors for recurrence after RFCA in patients with PersAF.

Impact of non-valvular atrial fibrillation on global cognitive function and executive function

Objective: To explore the impact of non-valvular atrial fibrillation (AF) on the global cognitive function and executive function of patients without dementia, and to observe the differences between different types of AF. Methods: This research is a prospective and cross-sectional study. Non-dementia patients admitted to the department of neurology in the third people's hospital of Chengdu from July 2018 to July 2019 were included. Patients with non-valvular AF were included in the AF group and those with sinus rhythm were included in the control group. General clinical data and compared global cognitive function (mini-mental state examination (MMSE) and montreal cognitive assessment (MOCA)) and executive function (shape trails test (STT) and stroop color and word test (SCWT)) data were obtained and compared between 2 groups, and between different AF type groups. Results: A total of 386 participants were included, including 203 in AF group (52.6%), age was 68 (63, 71) years old, 119 were male (58.6%) and 183 in control group, age was 68 (63, 71) years old, 101 were male (55.2%). MMSE(28 (27, 29)) and MOCA (25 (22, 26)) scores were lower in AF group than those in control group (P<0.05), while STT-A time (84 (64, 140) s), STT-B time (248 (184, 351) s), STT time difference((159 (106, 245) s), SCWT-A time (50 (50, 50) s), SCWT-B time (55 (46, 63) s), SCWT-C time (100 (86, 120) s) and SCWT time interference (46 (34, 65) s) were higher than those in control group (P<0.05). Moreover, there was no difference in above indexes between paroxysmal AF and non-paroxysmal AF. Conclusion: The global cognitive function and executive function of patients with non-valvular AF are both decreased, while there is no obvious difference of the global cognitive function and executive function between paroxysmal AF and non-paroxysmal AF patients.

Maximum time between cardiac cycles in atrial fibrillation for assessing the risk of arterial thromboembolism

Aim. To assess the development of thromboembolic events in different types of atrial fibrillation (AF), which differ in the maximum time between cardiac cycles.Material and methods. The main group included 80 patients with permanent AF, while the control one — 88 people without AF. The following investigations were performed: echocardiography, 24-hour electrocardiographic (ECG) monitoring; ultrasound of extracranial arteries, aortic branches, lower limb arteries; sphygmography of the common carotid and posterior tibial arteries. If required, coronary angiography, cerebral angiography, brain computed tomography were performed. According to 24-hour ECG monitoring, all patients of the main group were divided into 2 subgroups (A and B) depending on the maximum time between cardiac cycles in AF: subgroup A (n=42) — patients with a maximum time between cardiac cycles &lt;1,5 seconds, subgroup B (n=38) — ≥1,5. The followup period lasted 1 year. During the follow-up period, the development of arterial thromboembolic events was analyzed.Results. The patients were comparable in key paraclinical characteristics and comorbidity profile. One-year follow-up period revealed a significantly higher incidence of stroke, transient ischemic attack, myocardial infarction, and distal arterial embolism of lower limb arteries in subgroup B. With an increase in the maximum time between cardiac cycles in AF, an increase in hemodynamic parameters of arterial vessels occurred as both proximal and distal arteries. A similar trend was also observed in the analysis of arterial kinetic parameters.Conclusion. Not only the fact of AF presence is important for assessing the risk of arterial thromboembolism, but also its features. The most unfavorable for prognosis is AF with a maximum time between cardiac cycles ≥1,5 seconds. An increase in intra-arterial hemodynamic parameters after a long pause between ventricular contractions in AF without intracardiac thrombosis can become a key factor in the development of complications with existing plaques, which can become a source of distal embolism.

Effect of radiofrequency catheter ablation on left atrial structure and function in patients with different types of atrial fibrillation

Radiofrequency catheter ablation (RFCA) is widely used to treat atrial fibrillation (AF), but its effect on left atrial (LA) remodeling in patients with AF is not completely clarified. Few studies have reported the changes in structure and function of the left atrium in patients with different types of AF after RFCA. To analyze the effect of RFCA on the LA structure and function in patients with nonvalvular paroxysmal AF, persistent AF and long-standing persistent AF (LSPAF). RFCA was performed in 180 patients with paroxysmal AF, persistent AF and LSPAF. The changes of LA structure and function in echocardiogram and speckle-tracking echocardiography findings were compared before the procedure, and at 1, 2, 3, 4 weeks, and 2, 3, 6, and 9–12 months after the procedure. There were 60 patients in the paroxysmal AF group, 60 in the persistent AF group and 60 patients in LSPAF group. The pre-procedure LA diameter and volume were smaller in the paroxysmal AF group than persistent AF and LSPAF group. There was no significant change of in the LA structure and function in the paroxysmal AF group within 1 year. In the persistent AF and LSPAF groups, LA structure (anteroposterior diameter, LA volume) significantly decreased, but remained larger than that in paroxysmal AF group. In persistent and LSPAF, function (LA ejection fraction, strain, strain rate) increased significantly within 1 week, then gradually increased. RFCA improved the LA structure and function and resulted in heart reverse remodeling, especially for persistent AF and LSPAF.

Atrial fibrillation: the difference in thromboembolic events prognosis

Abstract Funding Acknowledgements Type of funding sources: None. Aim To identify the difference between the thromboembolic events in different types of atrial fibrillation (AF). Materials and methods We included 188 patients with permanent AF (of them were 99 men and 89 women). According to the data of 24-hours ECG monitoring, all patients were divided into 3 groups depending on the duration of maximum pauses between ventricular complexes in AF: 1. Patients with a pause &amp;lt; 1 second (64 people). 2. Patients with a pause of ≥1, but &amp;lt;2 seconds (62 people). 3. Patients with a pause ≥ 2 seconds or more (62 people). In control group we included 80 patients without AF. All groups were identical in age, sex and comorbidities. All patients underwent transthoracic or transesophageal echocardiography (we excluded the intra-chamber thrombosis in all the patients as well as the left ventricle aneurisms), Doppler ultrasound of the brachiocephalic vessels, branches of the aorta, arteries of the lower extremities, renal arteries, lipids level. If it was indicated, we performed stress echocardiography, coronary angiography, renal artery angiography, computed tomography of brain with contrast. The patients of all groups were on the standard therapy recommended by current ESC guidelines. We were observing the patients for 1 year after the beginning of the investigation. The endpoints were at 3, 6 and 12 months after the primary visit. During these endpoints, we analyzed the development of thromboembolic complications. Results We analyzed the data obtained on thromboembolic complications in 1 year in patients of 1, 2, 3 groups and compared them with the control group. The most frequent incidence of complications was in group 3 compared with other groups and the control group. We believe that the risk factor for thromboembolic complications is not only the fact of permanent form of AF, but also what type of AF. The most unfavorable is AF with pauses between ventricular contractions of 2 seconds or more. Conclusion We consider to use the proposed functional classification of AF in clinical practice. Determination of the type of AF will largely determine the further management tactics of each patient, the prognosis of the thromboembolic complications. We supplemented the CHA2DS2-VASc score with the new independent risk factor – type of AF – in accordance to the maximum duration of pauses between cardiocycles.

Evaluating left atrial appendage function in a subtype of non-valvular atrial fibrillation using transesophageal echocardiography combined with two-dimensional speckle tracking

The use of transesophageal echocardiography (TEE) is a clinically feasible method for quantitative analysis of left atrial appendage (LAA) function. LAA dysfunction is closely associated with atrial fibrillation (AF)-related stroke. However, there are few studies on the changes in LAA function in patients with different types of AF. This study aimed to observe changes in LAA systolic motion and function in patients with different types of AF by using speckle-tracking echocardiography (STE). A retrospective study of 216 patients with non-valvular AF was conducted. The LAA was divided into three parts: the basal segment (B), middle segment (M), and top segment (A). Speck -racking technology was used to measure and record the forward strain values of the basal segment (B), middle segment (M), and top segment (A) of the LAA, and the peak positive strain dispersion of the LAA was calculated. The left atrial appendage mechanical dispersion (LAAMD) was defined as the standard deviation (SD) of the peak positive strain at each segment of the R-R interval. Partial speckle-tracking parameters of the LAA showed statistical significance between the two groups. The peak strain on the top segment of the LAA was reduced in the persistent atrial fibrillation (per-AF) group compared to the paroxysmal atrial fibrillation (par-AF) group [11.87 (6.47-20.12) vs. 16.02 (9.76-24.50); 12.66 (6.66-21.22) vs. 20.16 (14.16-30.56); both P<0.01]. In the group with lower LAAMD, the proportion of patients with persistent AF (per-AF) was higher (66.3% vs. 33.7%; P<0.001), the left atrial dilatation was more significant (45.80±5.656 vs. 42.85±4.867; P<0.001), the LAA filling velocity and LAA empty velocity were lower (42.35±20.354 vs. 51.0±20.599; 38.71±24.39 vs. 51.62±21.282; both P<0.001), the LAA ejection fraction was significantly lower (52.16±25.538 vs. 70.85±20.741; P=0.000), and the peak positive strains of the M and A of the LAA were lower than those in the higher LAAMD group. The deformability of the LAA is decreased diffusely in per-AF, especially in the A of the LAA. Compliance with LAA was worse in patients with per-AF than in those with par-AF.

Linear increase in the number of non-pulmonary vein triggers from paroxysmal to persistent and long-standing persistent AF in patients undergoing repeat procedure after successful isolation of pulmona

Abstract Introduction This study evaluated the prevalent triggers responsible for recurrence following successful PVI in different types of atrial fibrillation (AF). Methods Consecutive AF patients undergoing repeat catheter ablation with permanently isolated PV were included in the analysis. High-dose isoproterenol challenge (20- 30μg/min for 15–20min) was used to confirm PV reconnection and identify non-PV triggers. Circular mapping catheter (CMC) was used to map the site of origin of significant ectopic activity by comparing the activation sequence of the sinus beat with that of the ectopic beat. For the coronary sinus (CS), ablation catheter was positioned at the level of the mitral valve annulus, parallel to the one positioned in the CS. Left atrial appendage (LAA) firing was detected by placing the CMC in the left superior PV and thus recording far-field potentials from the LAA. Results This prospective study included 1850 AF patients undergoing repeat AF ablation (Table 1), of which 573 (31%) had received one and the remaining 1277 patients had received 2 earlier ablations. Permanent PVI was confirmed with isoproterenol challenge. Table 1 shows the distribution of non-PV triggers. A linear increase in the number of non-PV triggers was observed from PAF to PerAF to LSPAF. Significantly higher number of LSPAF patients had detectable non-PV triggers compared to PerAF and PAF cases. Conclusion We observed a linear increase in the number of non-PV triggers in PAF to PerAF and LSPAF patients experiencing recurrence with successful isolation of PVs. As non-PV triggers are often not targeted by operators, this could be the underlying mechanism for more frequent recurrences in non-paroxysmal AF. Funding Acknowledgement Type of funding sources: None. Table 1

Diagnostic accuracy of MicroRNA 208b level with respect to different types of atrial fibrillation

MicroRNAs (miRNA) are prerequisite for cardiovascular functions. miRNA miR-208 b is a cardio-specific miRNA with tissue (atrial) levels elevated in atrial fibrillation (AFib) and blood levels significantly elevated in myocardial infarction. We calculated serum levels of miR-208 b in paroxysmal and persistent AFib, embolic cerebrovascular accident patients with AFib as possible etiology and controls. There was a statistically significant change of miR-208 b levels in paroxysmal (p = 0.044) and persistent (p = 0.040) AFib patients, but not for embolic CVA patients. miR-208 b could serve as a new serum marker for paroxysmal AFib.

Relationship between serum uric acid levels and different types of atrial fibrillation: An updated meta-analysis

AimIncreasing evidence supports the hypothesis that high serum uric acid (SUA) levels are related to atrial fibrillation (AF). However, the incidence of AF in patients with hyperuricemia and SUA levels in different types of AF is not entirely clear. This meta-analysis was designed to evaluate the relationship between SUA and incidence of AF, and the variation in SUA levels in different types of AF. Data synthesisRelevant reports were searched for in Embase, PubMed and the Cochrane Library. A fixed-effects model combining relative risk (RR) and the corresponding 95% confidence interval (95% CI) was used to evaluate the correlation between SUA and AF. The standardized mean differences (SMDs) of SUA values were calculated using a random-effects model to evaluate the differences in SUA levels among different types of AF.A total of 31 studies with 504,958 participants were included in this research. The results from 8 cohort studies showed that high SUA levels significantly increased the incidence of AF [RR (95% CI): 1.92 (1.68–2.20); P < 0.01]. The results from 29 studies revealed that SUA levels elevated in patients with AF [SMD (95% CI): 0.55 (0.43–0.66); P < 0.001]. Meanwhile, SUA levels in new-onset AF [SMD (95%CI): 0.24 (0.10–0.38); P = 0.001], paroxysmal AF [SMD (95%CI): 0.52 (0.33–0.72); P < 0.001] and persistent AF [SMD (95%CI): 1.23 (0.98–1.48); P < 0.001] were significantly higher than that in patients without AF. ConclusionsHigh SUA levels had an obvious correlation with the occurrence rate of AF. In addition, SUA levels were significantly different among patients with new-onset, paroxysmal and persistent AF.

Clinical Characteristics and Management Practice among Patients Diagnosed with Atrial Ibrillation in Benghazi Libya, A Cross Sectional Study

Introduction: There are no data so far regarding the frequency and outcome of the different types of atrial fibrillation (AF) in the clinical setting for Libyan patients. Furthermore, it is unknown whether the actual clinical management and therapy of AF in Libya conform to the international guidelines. The aim of this study was to determine the frequency, demographic, and clinical characteristics of AF patients. Patients and Methods: Three hundred patients attending the outpatient clinic and cardiology department at Benghazi Medical Center and National Cardiac Center between May 2020 and October 2020 were included. Patients' data were obtained through medical records using the chart review. Patients were categorized into a clinical type of AF, based on the physician's perception of the AF at the time of presentation. Results: Three hundred patients with an established diagnosis of AF were enrolled, including 210 (70%) females and 90 (30%) males. The mean age at the time of diagnosis was 49.5 ± 21.5 years, with an age range of 29–79 years. Of them 139 (46.3%) were diagnosed as permanent AF, 132 (44%) paroxysmal AF, while new-onset AF was diagnosed in 29 (9.7%). The three clinical categories of AF were enrolled under the care of both cardiologists and internal medicine physicians, but permanent AF patients were more often enrolled under the care of a cardiologist. Patients with permanent AF were older compared with those with paroxysmal subtype (61.8 ± 9 and 50.1 ± 12, respectively), with significant female predominance (P = 0.03), and more often had coronary artery disease (CAD), valvular heart disease, and a previous stroke/TIA (P = 0.01, P = 0.124, and P = 0.002, respectively). Diabetes was the most prevalent associated medical condition, followed by hypertension and hyperlipidemia. CAD was diagnosed among 122 patients. Of permanent AF patients, 28 patients (20.1%) previously suffered from a stroke, mostly TIA, in contrast to 14 patients (10.6%) of the other AF patients. Conclusion: Our AF patients were characterized by an unfavorable cardiovascular risk profile. We recognize a lower rate of oral anticoagulation prescription, which needs further evaluation.

Research of spontaneous and stimulated functional activity of platelets in patients with different types of atrial fibrillation.

Platelet function testing is widely used to diagnose disorders of the cellular link of hemostasis. The study of platelet aggregation activity is relevant for the prevention of thromboembolic complications in atrial fibrillation and monitoring the effectiveness and safety of therapy. In this study, a comparative analysis of spontaneous and stimulated platelet aggregation in groups of patients with two types of atrial fibrillation was performed - paroxysmal and persistent. The effect of β-adrenoblocker therapy on platelet aggregation activity in patients with atrial fibrillation was also studied. Platelet aggregation activity was studied using the method of G. Born in the modification of Z.A. Gabbasov on a two-channel laser analyzer "Biola". Collagen at a concentration of 2 mg / ml and adrenaline in a concentration range of 2.5-10 μg / ml were used as aggregation-promoting agents. It has been established that spontaneous aggregation potential and collagen-induced platelet aggregation depend on the type of atrial fibrillation, as well as on the presence or absence of β-blockers in therapy. The response of platelets to stimulation with adrenaline depends, first of all, on the type of atrial fibrillation and the concentration of adrenaline in the reaction medium. The most significant changes were noted in the group of patients with a paroxysmal form atrial fibrillation, taking β-blockers in therapy.

Effects of catheter ablation on left atrial performance in different types of atrial fibrillation: a strain study

Abstract Background Atrial structural and functional changes may develop as a result of catheter ablation (CA) in patients with paroxysmal and persistent atrial fibrillation (AF). However, the relation between AF recurrence and atrial performance following CA is still under debate. Our aim is to describe the long-term effects of CA on LA remodeling and its correlates to the maintenance of sinus rhythm (SR). Methods We prospectively enrolled 178 consecutive patients (age: 63±9 years, 35% females) with paroxysmal AF undergoing first-CA (67%) or redo-CA (22%), and 20 individuals (11%) with long-standing persistent AF (PAF) undergoing first CA. All patients underwent comprehensive transthoracic echocardiography at baseline and at 12-month follow-up, including the assessment of reservoir and contractile strain (LAS) using two dimensional speckle tracking echocardiography in all three apical views. The study population was divided in two sub-groups according to AF recurrence during follow-up. Results During one-year follow-up, 144 (81%) patients maintained SR whereas 34 (19%) patients had AF recurrence [first-CA group 16 (13%), redo-CA group 8 (20%) and PAF group 10 (50%)]. Improvement of LAS was observed only in patients with paroxysmal and long-standing persistent AF who underwent the first CA and who remained in SR (Figure 1A, 1C). In contrast, recurrent AF was associated with absence of LAS improvement (Figure 1A, 1C). Different time course of LA performance was observed in the redo-CA group, i.e. LAS remained unchanged from baseline regardless of long-term maintenance of SR (Figure 1B). Moreover, at follow-up, no significant differences in LAS between redo-CA patients with SR versus AF were observed. Of note, in patients with long-standing persistent AF and SR, follow-up LAS increased to values observed in the redo-CA group. Conclusion LA performance following CA is strongly affected by complex interplay between extent of atrial electro-structural remodeling and CA procedure. Repeated wide CA might affects negatively LA compliance and contractility despite SR restoration. Figure 1. Reservoir and contractile LAS at Baseline and 12-month follow-up in the First-CA (1A), the Redo-CA (1B) and the long-standing persistent AF (1C) groups in patients who maintained SR versus patients who had AF recurrence. *p value &amp;lt;0.05 (baseline vs. follow-up). Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): International PhD programme in Cardiovascular Pathophysiology and Therapeutics (CardioPaTh).

Levels of platelet derived extracellular vesicles in the left atrial appendage are higher in patients with permanent atrial fibrillation

Abstract Introduction Atrial fibrillation (AF) is a frequent arrhythmic disease and one of the most important causes of thrombembolic disease due to intracardiac thrombus formation. The left atrial appendage has been identified as the structure, where thrombus formation typically takes place in AF patients. Previous studies have shown thrombus formation is more frequent in permanent, than in paroxysmal or persistent AF. Underlying causes for this finding, however, remain unclear. Recently, it has been shown, that large extracellular vesicles (Microvesicles, MVs) are mediators of platelet activation. The aim of this study is therefore to investigate if the AF subtype correlates with the regional abundance of platelet derived MVs in the left atrial appendage. Methods and results In order to address this question blood samples from 59 consecutive patients undergoing left and right atrial catheterization were collected from the right atrium (RA), the left atrium (LA) and the left atrial appendage (LAA). 49% of the patients had permanent AF, 34% had non-permanent AF and 17% had no history of AF. MVs were isolated from 150 μL citrate plasma by a four-step differential centrifugation protocol (20000g x 40 min as main pelleting step). The MVs were characterized by immunoblotting and nanoparticle tracking analysis. The size of the MVs ranged between 50 and 600 nm and the MVs were shown to carry typical markers such as Annexin V. For flowcytometric analysis and quantification, Calcein AM was used to identify vesicles and CD31-PE, CD41-APC, CD235a-PE-Cy7 were applied to differentiate between platelet-derived MVs (PMVs, CD41+ CD31+), endothelial cell-derived MVs (EMVs, CD41- CD31+) and Red blood cell-derived MVs (RMVs, CD235a+). Fluorescence minus one controls, a concentration row and detergent mediated degradation were used to confirm specific staining of MVs. Total MV numbers (Calcein + events) did not differ significantly between the three cardiac localizations. In the left atrial appendage, the proportion of PMV was significantly higher in permanent AF patients compared to non-permanent AF. EMV numbers only differed in the right atrium, where permanent AF patients exhibited significantly lower numbers of EMVs compared to no AF controls. No differences between the groups were detected for RMV. Conclusion In the present study, we found that PMV levels in the left atrial appendage correlate with the type of atrial fibrillation (permanent vs non-permanent). PMVs have been connected to platelet activation and thrombus formation. These results may help to better understand how different types of atrial fibrillation cause different rates of thrombus formation in the LAA. PMV and EMV numbers by AF subtype Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): Medical Faculty University Bonn