Sustained Arrhythmia Research Articles

Atrial fibrillation: primary prevention, secondary prevention, and prevention of thromboembolic complications: part 1.

Atrial fibrillation (AF), is the most common sustained cardiac arrhythmia. It was once thought to be benign as long as the ventricular rate was controlled, however, AF is associated with significant cardiac morbidity and mortality. Increasing life expectancy driven by improved health care and decreased fertility rates has, in most of the world, resulted in the population aged ≥65 years growing more rapidly than the overall population. As the population ages, projections suggest that the burden of AF may increase more than 60% by 2050. Although considerable progress has been made in the treatment and management of AF, primary prevention, secondary prevention, and prevention of thromboembolic complications remain a work in progress. This narrative review was facilitated by a MEDLINE search to identify peer-reviewed clinical trials, randomized controlled trials, meta-analyses, and other clinically relevant studies. The search was limited to English-language reports published between 1950 and 2021. Atrial fibrillation was searched via the terms primary prevention, hyperthyroidism, Wolff-Parkinson-White syndrome, catheter ablation, surgical ablation, hybrid ablation, stroke prevention, anticoagulation, left atrial occlusion and atrial excision. Google and Google scholar as well as bibliographies of identified articles were reviewed for additional references. In these two manuscripts, we discuss the current strategies available to prevent AF, then compare noninvasive and invasive treatment strategies to diminish AF recurrence. In addition, we examine the pharmacological, percutaneous device and surgical approaches to prevent stroke as well as other types of thromboembolic events.

Reviewing Atrial Fibrillation Pathophysiology from a Network Medicine Perspective: The Relevance of Structural Remodeling, Inflammation, and the Immune System.

Atrial fibrillation (AF) is the most common type of sustained arrhythmia. The numerous gaps concerning the knowledge of its mechanism make improving clinical management difficult. As omics technologies allow more comprehensive insight into biology and disease at a molecular level, bioinformatics encompasses valuable tools for studying systems biology, as well as combining and modeling multi-omics data and networks. Network medicine is a subarea of network biology where disease traits are considered perturbations within the interactome. With this approach, potential disease drivers can be revealed, and the effect of drugs, novel or repurposed, used alone or in combination, may be studied. Thus, this work aims to review AF pathology from a network medicine perspective, helping researchers to comprehend the disease more deeply. Essential concepts involved in network medicine are highlighted, and specific research applying network medicine to study AF is discussed. Additionally, data integration through literature mining and bioinformatics tools, with network building, is exemplified. Together, all of the data show the substantial role of structural remodeling, the immune system, and inflammation in this disease etiology. Despite this, there are still gaps to be filled about AF.

Real-world utilization of the pill-in-the-pocket method for terminating episodes of atrial fibrillation: data from the multinational Antiarrhythmic Interventions for Managing Atrial Fibrillation (AIM-AF) survey.

Atrial fibrillation (AF) is the most common sustained arrhythmia encountered in clinical practice. Episodes may stop spontaneously (paroxysmal AF); may terminate only via intervention (persistent AF); or may persist indefinitely (permanent AF) (see European and American guidelines, referenced below, for more precise definitions). Recently, there has been renewed interest in an approach to terminate AF acutely referred to as 'pill-in-the-pocket' (PITP). The PITP is recognized in both the US and European guidelines as an effective option using an oral antiarrhythmic drug for acute conversion of acute/recent-onset AF. However, how PITP is currently used has not been systematically evaluated. The recently published Antiarrhythmic Interventions for Managing Atrial Fibrillation (AIM-AF) survey included questions regarding current PITP usage, stratified by US vs. European countries surveyed, by representative countries within Europe, and by cardiologists vs. electrophysiologists. This manuscript presents the data from this planned sub-study. Our survey revealed that clinicians in both the USA and Europe consider PITP in about a quarter of their patients, mostly for recent-onset AF with minimal or no structural heart disease (guideline appropriate). However, significant deviations exist. See the Graphical abstract for a summary of the data. Our findings highlight the frequent use of PITP and the need for further physician education about appropriate and optimal use of this strategy.

L1 cell adhesion molecule may be a protective molecule for atrial fibrillation in patients with valvular heart disease

BackgroundAtrial fibrillation (AF) is the most prevalent sustained arrhythmia. L1 cell adhesion molecule (L1CAM) served as a crucial regulator of signaling pathways. This research sought to examine the clinical value and functions of soluble L1CAM in the serum of AF patients. MethodsIn total, 118 patients (valvular heart disease patients [VHD, total: n = 93; AF: n = 47; sinus rhythm (SR): n = 46] and healthy controls [n = 25]) were recruited in this retrospective study. Plasma levels of L1CAM were detected by enzyme-linked immunosorbent assays. The Pearson's correlation approach, as applicable, was used for analyzing the correlations. The L1CAM was shown to independently serve as a risk indicator of AF in VHD after being analyzed by the multivariable logistic regression. To examine the specificity and sensitivity of AF, receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used. A nomogram was developed for the visualisation of the model. We further evaluate the prediction model for AF using calibration plot and decision curve analysis. ResultsThe plasma level of L1CAM was substantially decreased in AF patients as opposed to healthy control and SR patients (healthy control = 46.79 ± 12.55 pg/ml, SR = 32.86 ± 6.11 pg/ml, AF = 22.48 ± 5.39 pg/ml; SR vs. AF, P < 0.001; control vs. AF, P < 0.001). L1CAM was significantly and negatively correlated with LA and NT-proBNP (LA: r = −0.344, P = 0.002; NT-proBNP: r = −0.380, P = 0.001). Analyses using logistic regression showed a substantial correlation between L1CAM and AF in patients with VHD (For L1CAM, Model 1: OR = 0.704, 95%CI = 0.607–0.814, P < 0.001; Model 2: OR = 0.650, 95% CI = 0.529–0.798, P < 0.001; Model 3: OR = 0.650, 95% CI = 0.529–0.798, P < 0.001). ROC analysis showed that inclusion of L1CAM in the model significantly improved the ability of other clinical indicators to predict AF. The predictive model including L1CAM, LA, NT-proBNP and LVDd had excellent discrimination and a nomogram was developed. The model had good the calibration and clinical utility. ConclusionL1CAM was shown to independently serve as a risk indicator for AF in VHD. In AF patients with VHD, the prognostic and predictive effectiveness of models incorporating L1CAM was satisfactory. Collectively, L1CAM may be a protective molecule for atrial fibrillation in patients with valvular heart disease.

Prevalence of arrhythmia in COVID-19 patients with mild/moderate and severe illness: a prospective cohort study

ABSTRACT Objectives The type of arrhythmias, and their prevalence in mild/moderate and severe COVID-19 patients admitted to the hospital are unknown from a prospective cohort study. Methods We did continuous electrocardiograms along with multiple ECGs in 305 consecutive hospitalized COVID-19 patients. Results The incidence of arrhythmias was 6.8% (21/305) in the target population. The incidence of arrhythmias was 9.2% (17/185) in patients with severe COVID-19 illness and 3.3% (4/120) in patients with mild/moderate COVID-19 illness with no significant difference (p = 0.063). All the arrhythmias were new-onset arrhythmias in this study. 95% (20/21) of these arrhythmias were atrial arrhythmia with 71.42% (15/21) being atrial fibrillation and one episode of sustained polymorphic ventricular tachycardia. No episode of high-grade atrioventricular block, sustained monomorphic ventricular arrhythmia, or torsades de pointes arrhythmias were observed in this study. The patients with arrhythmias were admitted to the intensive care unit (80.9% vs. 50.7%; p: 0.007), were on a ventilator (47.6% vs. 21.4%; p: 0.006), and had high in-hospital mortality (57.1% vs. 21.1%; p: 0.0001) than patients without arrhythmias. Conclusion Atrial arrhythmias were the most frequent arrhythmias in hospital-admitted COVID-19 patients with atrial fibrillation being the most common arrhythmia. Trial registration Clinical Trial Registry India (CTRI) (CTRI/2021/01/030788). (https://www.ctri.nic.in/)

Cross-Fourier analysis for differentiating prolonged and self-terminating ventricular tachycardia in isolated rat hearts

The interaction between the ventricles and atria in the heart is an important aspect of cardiac function. During ventricular arrhythmias, such as ventricular tachycardia and ventricular fibrillation, the atrial interbeat interval appears different from that of normal sinus rhythm, even though there is no direct electrical connection between the ventricles and atria. To understand this phenomenon, bivariate time-series Fourier analysis was performed on ventricular and atrial signals. The results showed different levels of correlation from the ventricles to the atria during ventricular arrhythmias. We found that low interaction was associated with self-terminating ventricular arrhythmias, while strong connections were mostly seen in sustained ventricular arrhythmias. These findings suggest that the underlying mechanism behind this interaction may be due to the presence of mechano-electrical coupling, which serves as a bridge from the ventricles to the atria (reciprocal connections).

Long-term safety and efficacy of renal sympathetic denervation in atrial fibrillation: 3-year results of the AFFORD study

BackgroundAtrial fibrillation (AF) is the most common sustained arrhythmia which has been associated with increased sympathetic nervous system activity and hypertension. Recent evidence indicated that renal sympathetic denervation (RDN) could safely contribute to an improvement in AF burden.ObjectiveTo investigate the long-term safety and efficacy of radiofrequency RDN in hypertensive patients with symptomatic AF.MethodsThis pilot study included patients with symptomatic paroxysmal or persistent AF (European Hearth Rhythm Association class ≥ II) despite optimal medical therapy, office systolic blood pressure (BP) ≥ 140 mmHg and ≥ 2 antihypertensive drugs. AF burden was measured using an implantable cardiac monitor (ICM), implanted 3 months prior to RDN. ICM interrogation and 24-h ambulatory BP monitoring were performed at baseline and at 3/6/12/24/36 months post RDN. The primary efficacy outcome was daily AF burden. Statistical analyses were performed using Poisson and negative binomial models.ResultsA total of 20 patients with a median age [25th–75th percentiles] of 66.2 [61.2–70.8] years (55% female) were included. At baseline, office BP ± standard deviation (SD) was 153.8/87.5 ± 15.2/10.4 mmHg, while mean 24-h ambulatory BP was 129.5/77.3 ± 15.5/9.3 mmHg. Baseline daily AF burden was 1.4 [0.0–10.9] minutes/day and throughout a 3-year follow-up period, no significant change was observed (− 15.4%/year; 95% confidence interval (CI) − 50.2%, + 43.7%; p = 0.54). The number of defined daily doses of antiarrhythmic drugs and antihypertensive drugs remained stable over time, while mean 24-h ambulatory systolic BP decreased with − 2.2 (95% CI − 3.9, − 0.6; p = 0.01) mmHg/year.ConclusionsIn patients with hypertension and symptomatic AF, stand-alone RDN reduced BP but did not significantly reduce AF burden up until 3 years of follow-up.Graphical abstract

PCSK9 inhibitors and incidence of arrhythmias in clinical practice: a phase IV multicentric study

Abstract Funding Acknowledgements Type of funding sources: None. Background PCSK9 inhibitors (PCSK9i) are a novel drug class indicated for the treatment of dyslipidaemia. PCSK9i have been shown to remarkably reduce cardiovascular events in patients at high risk, but little data is currently available regarding the incidence of atrial fibrillation, no reports exist on ventricular events or other cardiac arrhythmias, and is not documented if this drug class is safe regarding arrhythmias as a potential side effect. Purpose To study the incidence of arrhythmias in patients before and after treatment with PCSK9i. Methods All consecutive patients starting treatment with PCSK9 inhibitors, either evolocumab or alirocumab, were consecutively enrolled in two high-volume Italian arrhythmia centres. All patients were treated according to ESC guidelines for primary and secondary prevention. All patients failed to achieve the recommended LDL goals with standard treatment before the introduction of PCSK9i. Patients with familial hypercholesterolemia were excluded. All arrhythmic endpoints were collected in a one-year time frame before and after the first dose of PCSK9i. Results 191 patients were enrolled (mean age 63±15 years, 76.6% males) and followed up for one year. 13.2% were labelled as "statin-intolerant" and were treated only with ezetimibe, all the others had PCSK9i prescription on top of both statin and ezetimibe. The recommended LDL threshold was reached in 45.1% of patients at very high-risk and 76.7% at high-risk. 14.9% of all patients had a history of PACs and 15.6% had a history of PVCs. 7.8% had a previous diagnosis of atrial fibrillation, 2.1% of TRNAV and 6.4% of sustained ventricular arrhythmias. These 6.4% all had an ICD implanted for secondary prevention, while another 0.9% had a primary prevention indication. The total number of PACs in 24 hours decreased from 1260 to 800, although the difference was not statistically significant (p=0.058). Similar results were noted for PVCs (from 271 to 195 in 24 hours; p=0.089). The one-year incidence was 6.1% for atrial fibrillation, 2.3% for TRNAV and 3.8% for sustained ventricular arrhythmias, with no difference between the year before (all p=NS). Of all patients with an ICD and a history of appropriate ICD therapies (n=11, 5.7%) only one experienced appropriate therapies in the year after PCSK9i started. Conclusions The treatment with PCSK9 inhibitors does not significantly modify the risk of supraventricular or ventricular arrhythmias in patients with non-familial hypercholesterolemia. Preliminary data support the safety of this class of drug also regarding arrhythmic events.

The novel left atrial anterior 'seatbelt' line reduces sustained atrial arrhythmia by 72% compared to pulmonary vein isolation alone in a cohort of 400 virtual atria models

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No.860974. Background The success-rate of pulmonary vein isolation (PVI) is modest in persistent atrial fibrillation (AF), but additional empirical ablation, such as posterior wall isolation (PWI), has not been shown to reduce the rate of AF recurrence. The "seatbelt", an anterior linear ablation lesion connecting the right superior pulmonary vein to the mitral annulus, is a novel substrate modification approach that is yet to be tested in a large-scale randomised clinical trial. Purpose To use in-silico trials with human-based modelling and simulation to compare the efficacy of (i) PVI alone, (ii) PVI and PWI (PVI+PWI), or (iii) PVI and seatbelt (PVI+SB) for the prevention of atrial arrhythmia in large populations of virtual patient models. Methods AF was simulated in a cohort of 400 virtual atrial models with anatomical and electrophysiological variability, with AF persisting for &amp;gt;7 seconds defined as sustained. Models which sustained AF were each independently subjected to all three ablation approaches before repeating the AF induction protocol. Results Three hundred forty-four (86%) atrial models developed sustained AF at baseline. After applying the ablation lesions, substantially fewer models sustained atrial arrhythmias in the PVI+SB group (50 [14%] vs. 134 [39%] with PVI+PWI vs. 172 [50%] with PVI). PVI+SB was more effective than PVI and PVI+PWI in preventing both AF and atrial flutter (i.e., presence of a single rotor), since PVI and PVI+PWI led to the formation of anatomical re-entries around the rings of the pulmonary veins and the posterior wall of the left atrium, respectively (Figure). Therefore, PVI+SB restricted atrial flutter mainly to the right atrium (either anatomical, around the inferior cava vein, or functional, meandering throughout the venous portion of the right atrium, Figure). Importantly, in all three ablation strategies, the likelihood of AF recurrence was directly proportional to the surface area of the right atrium (AF probability increased 0.95%/cm², 0.88%/cm² and 0.56%/cm² after PVI+SB, PVI+PWI and PVI, respectively). The role of the right atrial size was less accentuated for PVI alone, since after the ablation the entire left atrial body was still available for rotor anchoring. Moreover, an enlarged left atrium enabled the appearance of micro-re-entries in the anterior and inferior wall of the left atrium, even after applying floor and roof lines. One atrial model additionally presented a rotor in the posterior wall of the left atrium after completely isolating it from the left atrial body. Conclusion(s) In a cohort of 400 virtual atrial models, PVI+SB reduced sustained atrial arrhythmias by 72% compared to PVI alone and by 64% to PVI+PWI, but AF could still originate in an enlarged right atrium.

Proteomics and recurrence of atrial fibrillation: a pilot study nested in the PREDIMAR trial

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Instituto de Salud Carlos III (ISCIII): Fondo de Investigación Sanitaria y Fondo Europeo de Desarrollo Regional and Proteored Regional Government of Navarra. Introduction Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia worldwide. Although catheter ablation is the most efficacious therapy to decrease AF recurrences, relapses occur in 30% of patients in the first year after ablation. Novel biomarkers of recurrence are needed for a better prediction and management of AF. Purpose In this pilot study we aimed to analyze the baseline proteome of subjects included in a case-control study nested within the PREDIMAR, a secondary prevention trial, to find differential proteins associated with AF recurrence. Methods We selected 18 cases defined as AF recurrence and 18 controls without AF recurrence matched by age. After QC process, baseline serum proteomics data (354 proteins) from 16 cases and 17 controls were obtained. Results Ten proteins were differentially represented in cases vs controls. keratin type I cytoskeletal 17 (K17) (FC=2.14; p=0.017) and endoplasmic bifunctional protein (GDH/6PGL) (FC=1.65; p=0.032). Eight proteins were underregulated among cases vs controls: c4b-binding protein alpha chain (C4bpA) (FC=0.64; p=0.006), coagulation factor XI (FXI) (FC=0.83; p=0.011), chloride intracellular channel protein 1 (CLIC1) (FC=0.62; p=0.017), haptoglobin (FC=0.37; p=0.021), immunoglobulin heavy constant alpha 2 (Ig alpha-2 chain C region) (FC=0.49; p=0.022), c4b-binding protein beta chain (C4bpB) (FC=0.73; p=0.028), N-acetylglucosamine-1-phosphotransferase subunit gamma (GlcNAc-1-phosphotransferase subunit gamma) (FC=0.61; p=0.033) and platelet glycoprotein Ib alpha chain (GP-Ib alpha) (FC=0.84; p=0.038). In multivariate logistic models, we found that even after the adjustment for age, sex, BMI, T2D and hypertension the direct association between K17 and the inverse association between C4bpA, F11, CLIC1, IGHA2, GNPTG and GP1BA with AF recurrence maintained the statistical significance. F11, C4bpA, C4bpB and CLIC1 have been previously associated with first arrhythmia or AF. This pilot study suggests that the circulating proteome may serve as a predictor of AF recurrence after catheter ablation.

Prevalence of sustained atrial arrythmias and treatment with zero fluoroscopy or near zero fluoroscopy catheter ablation in Slovenian orthotopic heart transplant recipients

Abstract Funding Acknowledgements Type of funding sources: None. Background Due to advances in surgical techniques and immunosuppression survival of heart transplant (HT) recipients has improved significantly, with that the prevalence of sustained atrial arrhythmias (SAA) in these patients is increasing. In HT recipients antiarrhythmic therapy options are limited. Radiofrequency ablation (RFA) represents a viable but underutilized option after other etiologies of SAA such as acute allograft rejection and vasculopathy are excluded. Limiting radiation exposure in HT recipients, who are exposed to 3,5 times (1) greater radiation dose compared to general population and are significantly more susceptible to develop malignancies, is essential. Purpose Our aim was to analyse prevalence and type of SAA in Slovenian orthotopic HT recipients and analyse feasibility and procedural outcomes of zero (ZF) or near zero fluoroscopy (NZF) RFA treatment approaches. Methods We performed a retrospective analysis of HT recipients between 2002 and 2022. We re-evaluated all available ECGs of suspected arrhythmias of included patients for presence and type of SAA. We further analysed HT patients that underwent RFA for SAA at our centre. All procedures were performed primarily with 3D electroanatomical mapping system and intracardiac echocardiography guidance. Either ZF or NZF approaches were used. The primary endpoint of all procedures was SAA termination and acute success was deemed when subsequent attempts to reinduce SAA failed. Long-term success was defined as the absence of any spontaneous SAA during 12-month follow-up. Results Among 364 consecutive HT recipients 19 patients (5,2%) were evaluated for SAA. Of those 7 (37%) presented as typical atrial flutters (AFL), 9 (47%) as atypical AFL, 2 (11%) as focal atrial tachycardia (FAT) and 1 (5%) as slow-fast atrioventricular nodal reentry tachycardia. In 2 (11%) patients with AFL, SAA was a result of acute allograft rejection. In 10 (53%) patients SAA occurred in first 3 months after HT. In the remaining 9 patients SAA occurred late, median 6,6 years after HT (25th-75th IQR: 7,7 years). RFA was performed in 7 (37%) patients. In all patients procedures were acutely successful however in 2 patients additional RFA procedures were needed for long-term success. All in all, 10 RFA procedures were performed (Table 1). All cases had macro or micro reentrant AFL with a median of 2,0 re-entry circuits mapped (25th-75th IQR: 3,3 re-entry circuits) during the procedure – that included typical cavotricuspid isthmus AFL, perimitral AFL, and several right atrium (RA) scar-related or incision related AFL. In 2 cases additional RA FAT were ablated. Five (50%) procedures were performed with ZF. No major procedure related complications were observed. Conclusion In HT recipients ZF or NZF RFA of SAA appears to be feasible and safe, but still underutilised, treatment option. Our case series demonstrates favourable acute and long-term outcomes however larger data is needed to support these results.

Value of implant-based telemonitoring in the high-risk population of ventricular assist device patients

Abstract Funding Acknowledgements Type of funding sources: None. Background Telemonitoring of heart failure (HF) patients is an evolving field. Prior studies presented promising results. However, the relevance of telemonitoring in the specific cohort of end-stage HF patients on ventricular assist device (VAD) therapy has not been analysed yet. Purpose This study aimed to evaluate the benefit of daily implant-based multiparameter-telemonitoring in high-risk HF-patients on VAD therapy with an implantable cardioverter-defibrillator (ICD) or a cardiac resynchronization defibrillator (CRT-D) including telemonitoring function. Beyond that, patients’ outcome and complication rates were evaluated. Methods A total of 30 end-stage HF-patients (65 ± 10 years, 89 % male) with a VAD and an ICD or a CRT-D with telemonitoring function were included in this observational single center study. Long-term follow-up data (4.28 ± 2.62 years) were assessed. Results All patients (n=30, 100%) received daily ICD or CRT-D telemonitoring. In the majority of patients (73%, n=22) the telemedical center had to take actions a mean of 3 times. Most events (84%, n=45) were identified within 24 hours. An acute alert due to sustained ventricular arrhythmias (VAs) occurred in 13 patients (65%) with 46% of them (n=6) requiring a shock delivery. Eight patients (62%) were hospitalized due to symptomatic VAs. Inadequate shocks were recognized in 3 patients (23%). In 12 patients (92%) immediate medication adjustments were recommended. Relevant lead problems were revealed in 13 patients (43%) with 6 patients (46%) undergoing consecutive lead revisions. Device-reprogramming was recommended in 50% of all VAD-patients (n=15). Compared to HF-patients without remote monitoring, daily telemonitoring significantly reduced the number of in-hospital device controls by 44% (p&amp;lt;0.01). Conclusions Daily implant-based-telemonitoring increased patient safety as it allowed for pre-emptive interventions and an immediate detection of cardiac arrhythmias and device/lead problems. Even in this high-risk HF-patient population, telemonitoring significantly reduced the number of in-hospital device-controls. Further studies are warranted to confirm these initial observations.

Cryoballoon ablation for atrial fibrillation in octogenarians: a propensity-score matching comparison with a cohort of younger patients

Abstract Funding Acknowledgements Type of funding sources: None. Background Atrial fibrillation (AF) is the most frequent sustained cardiac arrhythmia in adults with a current estimated prevalence between 2-4% in the general population. AF prevalence increases with advancing age and it is estimated that nearly 10% of octogenarians may be affected by this arrhythmia. In terms of safety and efficacy Cryoballoon ablation (CB-A) has become a valid option for achieving pulmonary vein isolation (PVI) in patients affected by AF. However, data regarding CB-A in octogenarians are still scarce and limited to single center experiences, therefore the present multicenter study aimed to compare the outcomes and complications of index CB-A in patients older than 80 years-old with a cohort of younger patients. Methods and Results We retrospectively enrolled 97 consecutive patients aged ≥ 80 years who underwent PVI by means of the second generation CB-A. This group was compared with a younger cohort of patients using a 1:1 Propensity score matching. After the matching, 70 patients of the elderly group were analyzed and compared with 70 younger patients (control group). Mean age was 81.4 ± 1.9 years among octogenarians and 65.2 ± 10.2 years in the younger cohort. The global success rate after a median follow up of 23 [18 - 32.5] months was 60.0% in the elderly group and 71.4% in the control group (p = 0.17) (Fig.1). Phrenic nerve palsy (PNP) was the most common complication occurring in a total of 11 patients (7.9%): in 6 (8.6%) patients for the elderly group and in 5 patients (7.1%) of the younger group (p = 0.51). PNP always recovered within the day after CB-A and did not hinder electrical isolation of any of the septal PVs. Only 2 (1.4 %) major complications occurred: 1 (1.4%) small femoral artery pseudoaneurysm in the control group, which resolved with a tight groin bandage without the need of surgical repair and 1 (1.4%) case of urosepsis in the elderly group with subsequent acute kidney failure and need of renal replacement therapy. Arrhythmia recurrence during the blanking period (BP) and need of electrical cardioversion (ECV) to restore sinus rhythm after PVI were found to be the only independent predictors of late arrhythmia relapses (Fig.2). Conclusions The present study showed that CB-A PVI is as feasible, safe and effective among octogenarians as it is in younger patients.

Evaluation of MADIT II risk stratification score among registry of heart failure patients with primary prevention ICD/CRTD device

Abstract Funding Acknowledgements Type of funding sources: None. Background Current guidelines advocate primary prevention ICD implantation for all symptomatic heart failure (HF) patients with low LVEF. As most patients will not use their device during lifetime, a score delineating subgroups with differential ICD benefit is crucial. The MADIT Risk Stratification Score (MRSS) based on 5 parameters including: age&amp;gt;70, Creatinine &amp;gt;1.4 mg/dl, QRS width &amp;gt;120ms, presence of AF, and NYHA &amp;gt;2, was developed for this purpose. Objective Evaluate MRSS among Israeli nationwide registry of HF patients implanted with prophylactic ICD/CRTD. Endpoints included overall mortality, sustained ventricular arrhythmia (VA), and competing risk of arrhythmic (VA-related) versus non-arrhythmic death, a surrogate for potential ICD survival benefit. Methods Study based on comprehensive registry of ICD/CRTDs implanted in Israel between 2011-2018. All registry patients were categorized into MRSS-based risk-groups (low-risk- MRSS 0, intermediate-risk- MRSS 1-5, very high-risk (VHR) group defined by Creatinine &amp;gt;2.5mg/dL). Univariate and Kaplan Meier analysis used to evaluate the association of risk groups with study endpoints. Results 2177 HF patients, implanted with a primary prevention ICD (1255, 58%) or CRTD (922, 42%) were included. There were 189 (8.7%) patients with sustained VA and 316 (14.5%) deaths during median follow-up (F/U) period of 2.5 years. A significant correlation was found between MRSS-based risk subgroups and overall mortality (p 0.001). However, MRSS association with sustained VA was weak (p 0.2). Notably, the MRSS-based very high-risk (VHR) subgroup had an exceptionally high mortality but low VA incidence. Competing risk of arrhythmic versus non-arrhythmic death revealed a large and significant ICD survival benefit among the low and intermediate MRSS-based risk subgroups, with 10.2 and 12.3 months survival gained over 3-year F/U period among these subgroups, respectively (p 0.001). The VHR subgroup in contrast, showed a minimal non-significant ICD survival benefit. Conclusions Use of MRSS among a contemporary real-world registry of HF patients revealed subgroups with differing ICD survival benefit, suggesting it as a universal tool to predict ICD survival benefit. MRSS-based VHR subgroup may not gain survival benefit from prophylactic ICD implant.

Left-ventricular non-compaction and ventricular arrhythmias

Abstract Funding Acknowledgements Type of funding sources: None. Background Left ventricular non-compaction (LVNC) is a rare, although underdiagnosed, cardiomyopathy deriving from the incomplete development of myocardial tissue. Its presentations range from heart failure to embolism and arrhythmic events with the latter being the most frequent cause of death. Purpose To define the incidence of arrhythmic complications in LVNC and describe the interplay between systolic dysfunction and ventricular events. Methods This is a retrospective evaluation of a prospectively-collected database including all consecutive patients with a definitive diagnosis of LVNC followed-up at the Cardiomyopathy Clinic of our institution from October 2009 to August 2022. We conducted a follow-up analyzing the possible correlation between baseline characteristics and a composite outcome of ventricular arrhythmias (sustained VT or VF), appropriate ICD interventions and sudden cardiac death (SCD). We also extracted a sample from our population with preserved LVEF and compared global longitudinal strain (GLS) in compacted and non-compacted segments. Results 44 patients (29 males, 65.9%) were enrolled in the study; 36 patients (81.8%) underwent a cardiac MRI and 34 (77.3%) resulted positive for Petersen criteria. 26 patients (59.1%) had positive echocardiographic criteria, while 18 patients (40.9%) were positive for both MRI and echocardiographic criteria. Five patients (11%) experienced an arrhythmic event during a median follow-up of 2 years (1 VT, 1 VF and 3 patients with appropriate ICD interventions). No clinical, ECG or lab predictors were found for arrhythmic events apart from a history of non-sustained or sustained ventricular arrhythmias, which was associated with a 36% increased risk of subsequent VT/VF episodes (RR 1.36; 95% CI 1.01-1.85; p=0.01). Notably, LVEF (which was ≤35% in 11% of the patients) was not able to significantly discriminate arrhythmic risk (50.7±13.0% vs. 50.2±7.8%; p=ns). Out of 9 patients with normal LVEF and normal GLS, the segmental LS resulted better in non-compacted cardiac segments vs. compacted ones (-20.0±4.6% vs. -17.5±4.9%; p=0.03). This was mainly due to an increase deformation of endocardial layers of non-compacted segments (-26.4±6.6% vs. -19.7±6.6%; p≤0.001), while epicardial layers were similar in compacted versus non-compacted segments. Conclusions LVNC represents a poorly understood condition where a mixture of genetic and molecular mechanisms create a fertile substrate for the origin of ventricular arrhythmias. Our population reflects this pattern by showing a high percentage (5.5%/year) of patients experiencing the composite outcome. GLS was higher in non-compacted segments due to an apparent hyperdeformation of endocardial layers. In our opinion, this evidence represents a valid resource and a useful weapon to distinguish LVNC from other differential diagnoses such as, for example, dilated cardiomyopathy.

Self-taught ultrasound-guided axillary vein access for pacemaker implantations - complication rates and outcomes

Abstract Funding Acknowledgements Type of funding sources: None. Background Cardiac implantable electronic devices (CIEDs) are the mainstream therapy for advanced atrioventricular block or sustained ventricular arrhythmia. EHRA survey (1) showed that cephalic vein dissection and blind subclavian vein puncture are the preferred techniques for the implantation of CIED leads in European centres. Ultrasound (US) guided axillary puncture has emerged as feasible alternative for safe and rapid venous access for lead implantation. However, insufficient evidence to support its widespread adoption. Aim To compare the complication rates and clinical outcomes of CIED implantations utilising self-taught US guided axillary puncture versus non-US guided venous access (Subclavian puncture and fluroscopy guided axillary puncture). Assess the mean time to gain venous access and overall success rate in US guided technique. Methods Retrospective , observational study across two sites involving all CIED implantations of four experienced implanters over the year from January 2021 - June 2022. Patient's demographics, venous access time, complications and clinical outcomes were extracted from electronic database. US axillary access technique was self-taught. Results and Outcomes Venous access was obtained by US Guided axillary puncture in 146 patients, non-US guided in 208 patients. Successful axillary venous access by ultrasound guidance is 97%(146/151) with mean time to venous access of 2.1 minutes. Baseline demographics (age, gender) and comorbidities (hypertension, diabetes, cardiomyopathy, coronary artery disease, dyslipidemia, renal failure, oral steroid use, nicotine use) were similar between both US-guide and non-US guided groups, usage of oral anticoagulations (32.9% vs 39.4%,p=0.208) and antiplatelet agents(28.1% vs 35.1%,p=0.164) were not statistically different. Greater proportion of dual chamber pacemakers were implanted in US guided access group versus non-US guided (39.7% vs 27.9%,p=0.015). US Guided axillary access resulted in lower overall complication rate (2.1% vs 8.9%, p=0.0196): lower risk of pneumothorax (0% vs 3.8%,p=0.0236), lower risk of haemathoma (0% vs 3.4%,p=0.0448). No difference in short term pocket/lead infection or lead displacement. Severe vascular complications remains low in both groups. Stepwise binary regression analysis demonstrated US guidance as independent predictor of lower overall complication rate, odd-ratio 0.195 (95% CI 0.054 - 0.706). Summary: This multi-centered, retospective observational study demonstrated that US guided axillary access has high overall success rate, not time consuming and resulted in lower complication rates (especially pneumothorax and pocket haemathoma), despite the US access technique being self-taught and have greater proportion of dual chamber device implantations. US guided axillary access is demonstrated to be independently associated with 5-fold lower risk of complications.

Diagnostic accuracy of smart gadgets/wearable devices in detecting atrial fibrillation in primary prevention: a meta-analysis

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Atrial fibrillation (AF) is the most common sustained arrhythmia and an important risk factor for stroke and heart. Recent technology advances have allowed for heart rhythm monitoring using smart gadgets/wearable devices which can be used for early AF diagnosis. Purpose We performed a systemic review and meta-analysis to assess the accuracy of AF diagnosis by smart gadgets/wearable devices in primary prevention. Methods We systematically searched Medline, Embase and Cochrane electronic databases up to September 22th, 2022 for observational studies of the diagnostic accuracy of smartphone application, wrist-worn wearables and external devices in detecting AF in primary prevention. Studies with 12-lead ECG or single-lead ECG interpreted by a cardiologist as gold standard were included. We calculated the area under the curve (AUC) of the summary receiver operating characteristic curves (SROC) and pooled sensitivities and specificities. Results A total of 28 studies were included enrolling 13463 patients, 57%(95% CI: 55-59%) male with average age of 65.3years (95% CI: 60.1 – 70.4). The pooled prevalence of AF was found to be 13% (95% CI 10 – 15%). In the overall analysis of all devices, the AUC was 0.99 (95% CI: 0.97-0.99)(Figure 1), the sensitivity 93%(95% CI: 89 – 95%) and the specificity 97%(95% CI: 95 – 98%) (Figure 2). Wrist-worn wearables had AUC of 0.97 (95% CI: 0.94-0.99), the sensitivity 83%(95% CI: 52 – 96%) and the specificity 98%(95% CI: 87 – 100%). Smartphone applications had AUC of 0.97 (95% CI: 0.96-0.98), the sensitivity 92%(95% CI: 77 – 98%) and the specificity 95%(95% CI: 91 – 97%). External devices had AUC of 0.99 (95% CI: 0.97-0.99), the sensitivity 94%(95% CI: 91 – 96%) and the specificity 97%(95% CI: 95 – 98%). Single-lead ECG had AUC of 0.99 (95% CI: 0.97- 0.99), the sensitivity 93%(95% CI: 88 – 96%) and the specificity 91%(95% CI: 78 – 97%). photoplethysmography pulse waveform technology (PPG) had AUC of 0.97 (95% CI: 0.96-0.98), the sensitivity 91%(95% CI: 78 – 97%) and the specificity 95%(95% CI: 91 – 97%). Pulse beat interval technology had AUC of 0.99 (95% CI: 0.98-0.99), the sensitivity 95%(95% CI: 90 – 98%) and the specificity 96%(95% CI: 93 – 98%) Conclusions Smartphone application, wrist-worn devices and external devices have excellent diagnostic accuracy in atrial fibrillation diagnosis in primary prevention.

Diagnostic accuracy of smartwatch in detecting atrial fibrillation: a systemic review and meta-analysis

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Atrial fibrillation (AF) is the most common sustained arrhythmia and an important risk factor for stroke and heart. Recent technology advances allowed for heart rhythm monitoring using Smartwatches which can be used for early AF diagnosis. Purpose We performed a systemic review and meta-analysis to assess the accuracy of AF diagnosis by smartwatches. Methods We systematically searched Medline, Embase and Cochrane electronic databases up to September 28th, 2022 for observational studies of the diagnostic accuracy of smartwatches devices in detecting AF. Studies with 12-lead ECG or single-lead ECG interpreted by a cardiologist as gold standard were included. We calculated the area under the curve (AUC) of the summary receiver operating characteristic curves (SROC) and pooled sensitivities and specificities. Results A total of 20 studies were included enrolling 3447 patients, 57%(95% CI: 55-59%) male with average age of 68.3years (95% CI: 63 – 74). The pooled prevalence of AF was found to be 40% (95% CI 27 – 53%). In the overall analysis of all smartwatches, the AUC was 0.99 (95% CI: 0.98-1.00) (Figure 1), the sensitivity 94%(95% CI: 90 – 96%) and the specificity 97%(95% CI: 95 – 98%) (Figure 2). Smartwatches in primary prevention showed an AUC of 0.97 (95% CI: 0.96-0.99), sensitivity of 83%(95% CI: 52 – 96%) and specificity of 98%(95% CI: 87 – 100%) whereas in secondary prevention showed an AUC of 0.99 (95% CI: 0.98-1.00), sensitivity of 95%(95% CI: 94 – 97%) and specificity of 97%(95% CI: 96 – 98%). In the subgroup analysis by technology, smartwatches with single lead ECG showed an AUC of 0.99 (95% CI: 0.98-1.00), sensitivity of 95%(95% CI: 89 – 97%) and specificity of 97%(95% CI: 94 – 99%) whereas smartwatches with photoplethysmography pulse waveform technology showed an AUC of 0.99 (95% CI: 0.97-0.99), sensitivity of 95%(95% CI: 92 – 96%) and specificity of 97%(95% CI: 95 – 99%). Conclusions Smartwatches proved an excellent diagnostic accuracy for AF diagnosis.

Adverse events associated with AveirTM VR leadless pacemaker: A Food and Drug Administration MAUDE database study.

Leadless pacemaker (LP) offers an innovative approach for treating bradyarrhythmia, thus avoiding pacemaker pocket and lead-related complications. The Food and Drug Administration (FDA) has recently approved the Aveir™ leadless pacing system (screw-in type LP). We queried the FDA MAUDE database to study the safety profile and assess the types of complications with this relatively novel device technology. A MAUDE database search was conducted on January 20, 2023, for reports received post-FDA approval to capture all adverse events. A total of 98 medical device report were reported for Aveir™ LP. After excluding duplicate, programmer-related, or introducer-sheath-related entries (n = 34), 64 entries were included. The most commonly encountered problem was high threshold/noncapture (28.1%, 18 events), followed by stretched helix (17.2%, 11 events) and device dislodgement (15.6%, ten events-5 intraprocedural, while 5 in the postoperative Day 1). Other reported events included high impedance (14.1%, nine events), sensing issues (12.5%, eight events), bent/broken helix (7.8%, five events), premature separation (4.7%, three events), interrogation problem (3.1%, two events), low impedance (3.1%, two events), premature battery depletion (1.6%, one event) and inadvertent MRI mode switch (1.6%, one event) and miscellaneous (15.6%, n = 10). There were eight serious patient injury events-pericardial effusion requiring pericardiocentesis (7.8%, five events) due to cardiac perforation that resulted in two deaths (3.1%) followed by sustained ventricular arrhythmias (4.6%, n = 3). In our study assessing the real-world safety profile of the Aveir™ LP, serious adverse events have been reported-life-threatening ventricular arrhythmias, pericardial effusion, device explantation/reimplantation, and death.

P265 REAL–WORLD SINGLE CENTER EXPERIENCE WITH THE WEARABLE CARDIOVERTER DEFIBRILLATOR: SEX DIFFERENCES IN RISK STRATIFICATION FOR SUDDEN CARDIAC DEATH

Abstract Background Previous studies established a role for the wearable cardioverter defibrillator (WCD) in patients with transient risk os sudden cardiac death ( SCD) . The WEARIT–II Registry highlighted an higher burden of ventricular and atrial arrhythmic events in women than in men, in spite of a similar ICD implantation rates. Objectives We aimed to describe the sex differences in WCD use and compliance. Moreover we reviewed the rate of cardiac events detected with WCD and the rate of ICD implantation in women in a real–world single center experience. Methods and results Between August 2017 and June 2022, 60 consecutive patients receiving a WCD at Piacenza Hospitals were retrospectively included in this analysis: mean age 66.9±11.9 years, 56.6% with ischaemic cardiomyopathy, 38.3% with dilated cardiomyopathy, 5% after implantable cardioverter–defibrillator explant. 8 patients were women (13.3%). Women and men presented similar clinical characteristics. Median WCD usage period and median daily wear time were not different between women and men (49.6±25.3 vs 51.8±32.8 days, 23.6±0.3 vs 23.1±1.7 hours, respectively). No ventricular fibrillation was detected in the monitoring period. Non–sustained ventricular tachycardia and atrial arrhythmias were similar between women and men. However, ICD implantation rate at the end of WCD use was significantly lower in women than and men (25% vs 61.5%; p&amp;lt; 0.01). Conclusions In this real word analysis WCD was underused in women despite a nice compliance. A similar burden of ventricular and atrial arrhythmic events were detected, with a lower ICD implantation rate at the end of WCD use in women than in men.