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Introduction: Catheter ablation of persistent atrial fibrillation yields sub-optimal success rates partly due to the considerable heterogeneity within the patient population. Identifying distinct patient phenotypes based on post-ablation prognosis could improve patient selection for additional therapies and optimize treatment strategies., Methods: We studied all patients who underwent catheter ablation of persistent atrial fibrillation in the DECAAF II trial. Out of 44 participating centers, 25% were randomly chosen as a validation set. A Gradient Boosting Method determined essential features for arrhythmia recurrence prediction and the number of clusters was determined according to the average silhouette width. K-medoids cluster analysis identified subgroups based on these features, and Kaplan-Meier curves were further compared among different clusters., Results: Among 815 patients, 570 served as a training set and 245 as a validation set. Using the training set, the GBM model achieved an AUC of 0.874. K-medoids cluster analysis used LA volume, BMI, baseline fibrosis, and age, resulting in two clusters. Cluster 1 patients were older, had higher baseline fibrosis, higher BMI, and greater LA volume compared to Cluster 2. Atrial arrhythmia recurrence rates were significantly higher in Cluster 1 (51.7% vs. 35.0%, p = 0.0002), and survival analysis showed a significant difference in primary recurrence outcomes (HR = 1.71, p < 0.0001). The validation set confirmed these findings., Conclusion: Utilizing machine learning, we identified a high-risk cluster for procedural failure in catheter ablation of persistent atrial fibrillation within the DECAAF II trial population. The primary differentiating factors of this high-risk cluster include older age, high left atrial fibrosis, elevated BMI, and increased left atrial volume., (© 2024 Wiley Periodicals LLC.)

Background: There is a strong relationship between left atrial (LA) remodeling and ischemic stroke (IS) risk in atrial fibrillation (AF) patients. The Efficacy of Delayed Enhancement MRI-Guided Ablation vs. Conventional Catheter Ablation of Atrial Fibrillation (DECAAF-II) is the biggest MRI-based, randomized, multicenter clinical trial performed on persistent AF patients. The aim of this study is to evaluate the relationship between history of stroke and atrial fibrosis in the DECAAF II population., Methods: Persistent AF patients who underwent Late Gadolinium Enhancement Magnetic Resonance Imaging (LGE-MRI) were included in the study and divided into two different groups: those with a history of stroke and those without. Propensity score matching was performed to adjust for covariates. Atrial fibrosis was compared in both groups. Then, patients were divided into different fibrosis groups, using three different cut-offs of baseline atrial fibrosis: ≥ 15%, ≥ 20%, and ≥ 25%. Univariate logistic regression and adjusted multivariate analysis were performed to assess the effect of clinical characteristics and risk factors on baseline fibrosis., Results: Eight-hundred forty-three patients were recruited in DECAAF II, of whom 70 (8.3%) had a history of stroke. Patients with history of stroke had a higher prevalence of hypertension (p = 0.043), diabetes (p = 0.014), and hyperlipidemia (p = 0.001). Seventy patients with no history of strokes were matched with patients with history of stroke to adjust for covariates using propensity score analysis. Patients in the stroke group had a significantly higher level of fibrosis than those without (20.2% vs. 8.1%, p = 0.017). Increased age was a significant predictor of all three baseline fibrosis classes (≥ 15%, ≥ 20%, and ≥ 25%). Additionally, history of stroke was found to be a predictor of baseline fibrosis ≥ 25% even after adjusting for other clinical characteristics and risk factors (OR = 1.98 [1.14-3.43], p = 0.01)., Conclusions: Left atrial fibrosis level greater than 25% correlates with the history of previous stroke episodes in patients with persistent atrial fibrillation., Competing Interests: Declarations. Conflict of interest: NM reports having received consulting fees from Biosense Webster, Boston Scientific, and AtriCure. NM also reports being a speaker for Abbott, Biosense Webster, AtriCure, and Sanofi. NM also reports receiving research support Abbott, Medtronic, Biosense Webster, Siemens, GE, Boston Scientific, Sanofi, and Samsung. NM also reports having a family member as the CEO of Cardiac Designs. NM also reports being the founder of Marrek, being named in a patent issued for MRI fibrosis imaging, and being a previous shareholder of Cardiac Designs. All other co-authors have no relevant conflict of interest. The DECAAF II trial was funded by Medtronic, GE, Siemens, Boston Scientific, Biosense Webster, and Abbott., (© 2024. The Author(s).)

Purpose of Review: To examine the concept of time in target range for blood pressure (BP) management, exploring its calculation methods, implications for patient outcomes, and potential use in patient care., Recent Findings: Recent post-hoc analyses of clinical trials and observational studies highlight the importance of BP time in target range in predicting cardiovascular outcomes. Higher time in target range correlates with reduced risks of major adverse cardiovascular events including heart failure, stroke, myocardial infarction and all-cause mortality. Additionally, longer time in target range decreases the risk of incident atrial fibrillation and risk of developing dementia. BP time in target range is a novel metric offering valuable insights into BP control and its impact on clinical outcomes. Higher time in target range is consistently associated with better cardiovascular outcomes across various patient populations. However, the clinical application of BP time in target range requires further investigation through prospective clinical trials and real-world studies. Integrating wearable devices for continuous BP monitoring could enhance the practical utility of BP time in target range in hypertension management., (© 2024. The Author(s).)

Background: Catheter ablation (CA) improves clinical outcomes in patients with atrial fibrillation (AF) and heart failure (HF) with reduced ejection fraction (HFrEF). We aimed to evaluate the impact of CA on clinical and quality-of-life outcomes across HF subtypes., Methods: All patients undergoing AF ablation at a tertiary center were enrolled in a prospective registry and included in this study (2013-2021). The primary end point was AF recurrence. Secondary end points included AF-related hospitalizations and quality-of-life outcomes. Patients were categorized according to their HF status: no HF, HFrEF, HF with mildly reduced ejection fraction (HFmrEF), and HF with preserved ejection fraction (HFpEF)., Results: A total of 7020 patients were included (80% no HF, 8% HFrEF, 7% HFmrEF, and 5% HFpEF). Over 3 years, the cumulative incidence of AF recurrence after ablation was as follows: HFpEF (53%), HFmrEF (41%), HFrEF (41%), and no HF (34%); P <0.01. Multivariable Cox analyses confirmed these findings using no HF group as reference (HFpEF: hazard ratio, 1.47 [95% CI, 1.21-1.78]; HFmrEF: hazard ratio, 1.23 [95% CI, 1.04-1.45]; and HFrEF: hazard ratio, 1.17 [95% CI, 1.01-1.37]; P <0.05 for all). In all groups, CA resulted in a significant reduction of AF-related hospitalization (mean rate per 1 patient-years [before and after CA]; HFpEF [1.8 versus 0.3], HFmrEF [1.1 versus 0.2], HFrEF [1.1 versus 0.2], and no HF [1 versus 0.1]; P <0.01 for each comparison) and significant improvement in quality of life as measured by both the AF symptom severity score and the AF burden score ( P <0.01 for the comparison between baseline and follow-up for each score when tested separately)., Conclusions: AF recurrence rates after CA were higher in patients with HF compared with those without HF, with patients with HFpEF being at the highest risk of recurrence. Nonetheless, CA was associated with a significant reduction in AF symptoms, AF-related hospitalization, and HF symptoms in most patients irrespective of HF subtypes., Competing Interests: Dr Hussein receives research grant support from Boston Scientific. The other authors report no conflicts.

Aims: Traditional atrial fibrillation (AF) recurrence after catheter ablation is reported as a binary outcome. However, a paradigm shift towards a more granular definition, considering arrhythmic or symptomatic burden, is emerging. We hypothesize that ablation reduces AF burden independently of conventional recurrence status in patients with persistent AF, correlating with symptom burden reduction., Methods and Results: Ninety-eight patients with persistent AF from the DECAAF II trial with pre-ablation follow-up were included. Patients recorded daily single-lead electrocardiogram (ECG) strips, defining AF burden as the proportion of AF days among total submitted ECG days. The primary outcome was atrial arrhythmia recurrence. The AF severity scale was administered pre-ablation and at 12 months post-ablation. At follow-up, 69 patients had atrial arrhythmia recurrence and 29 remained in sinus rhythm. These patients were categorized into a recurrence (n = 69) and a no-recurrence group (n = 29). Both groups had similar baseline characteristics, but recurrence patients were older (P = 0.005), had a higher prevalence of hyperlipidaemia (P = 0.007), and had a larger left atrial (LA) volume (P = 0.01). There was a reduction in AF burden in the recurrence group when compared with their pre-ablation burden (65 vs. 15%, P < 0.0001). Utah Stage 4 fibrosis and diabetes predicted less improvement in AF burden. The symptom severity score at 12 months post-ablation was significantly reduced compared with the pre-ablation score in the recurrence group, and there was a significant correlation between the reduction in symptom severity score and the reduction in AF burden (R = 0.39, P = 0.001)., Conclusion: Catheter ablation reduces AF burden, irrespective of arrhythmia recurrence post-procedure. There is a strong correlation between AF burden reduction and symptom improvement post-ablation. Notably, elevated LA fibrosis impedes AF burden decrease following catheter ablation., Competing Interests: Conflict of interest: N.M. reported Marrek (founder) and ECG Check (previous shareholder) outside the submitted work; a patent was issued for MRI fibrosis imaging. No other disclosures were reported., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Background: The WEAICOR (Wearables to Investigate the Long Term Cardiovascular and Behavioral Impacts of COVID-19) study was a prospective observational study that used continuous monitoring to detect and analyze biometrics. Compliance to wearables was a major challenge when conducting the study and was crucial for the results., Objective: The aim of this study was to evaluate patients' compliance to wearable wristbands and determinants of compliance in a prospective COVID-19 cohort., Methods: The Biostrap (Biostrap USA LLC) wearable device was used to monitor participants' biometric data. Compliance was calculated by dividing the total number of days in which transmissions were sent by the total number of days spent in the WEAICOR study. Univariate correlation analyses were performed, with compliance and days spent in the study as dependent variables and age, BMI, sex, symptom severity, and the number of complications or comorbidities as independent variables. Multivariate linear regression was then performed, with days spent in the study as a dependent variable, to assess the power of different parameters in determining the number of days patients spent in the study., Results: A total of 122 patients were included in this study. Patients were on average aged 41.32 years, and 46 (38%) were female. Age was found to correlate with compliance (r=0.23; P=.01). In addition, age (r=0.30; P=.001), BMI (r=0.19; P=.03), and the severity of symptoms (r=0.19; P=.03) were found to correlate with days spent in the WEAICOR study. Per our multivariate analysis, in which days spent in the study was a dependent variable, only increased age was a significant determinant of compliance with wearables (adjusted R 2 =0.1; β=1.6; P=.01)., Conclusions: Compliance is a major obstacle in remote monitoring studies, and the reasons for a lack of compliance are multifactorial. Patient factors such as age, in addition to environmental factors, can affect compliance to wearables., (©Mario Mekhael, Chan Ho, Charbel Noujaim, Ala Assaf, Hadi Younes, Abdel Hadi El Hajjar, Humza A Chaudhry, Brennan Lanier, Nour Chouman, Noor Makan, Botao Shan, Yichi Zhang, Lilas Dagher, Omar Kreidieh, Nassir Marrouche, Eoin Donnellan. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 05.04.2023.)

Aims: The aim of our study was to assess differences in post-ablation atrial fibrillation (AF) recurrence and burden and to quantify the change in LVEF across different congestive heart failure (CHF) subcategories of the DECAAF-II population., Methods and Results: Differences in the primary outcome of AF recurrence between CHF and non-CHF groups was calculated. The same analysis was performed for the three subgroups of CHF and the non-CHF group. Differences in AF burden after the 3-month blanking period between CHF and non-CHF groups was calculated. Improvement in LVEF was calculated and compared across the three CHF groups. Improvement was also calculated across different fibrosis stages. There was no significant differences in AF recurrence and AF burden after catheter ablation between CHF and non-CHF patients and between different CHF subcategories. Patients with heart failure with reduced ejection fraction (HFrEF) experienced the greatest improvement in EF following catheter ablation (CA, 16.66% ± 11.98, P < 0.001) compared to heart failure with moderately reduced LVEF, and heart failure with preserved EF (10.74% ± 8.34 and 2.00 ± 8.34 respectively, P-value < 0.001). Moreover, improvement in LVEF was independent of the four stages of atrial fibrosis (7.71 vs. 9.53 vs. 5.72 vs. 15.88, from Stage I to Stage IV respectively, P = 0.115)., Conclusion: Atrial fibrillation burden and recurrence after CA is similar between non-CHF and CHF patients, independent of the type of CHF. Of all CHF groups, those with HFrEF had the largest improvement in LVEF after CA. Moreover, the improvement in ventricular function seems to be independent of atrial fibrosis in patients with persistent AF., Competing Interests: Conflicts of interest: Dr. Marrouche reports receiving grant support and consulting fees from Abbott, Medtronic, Biosense Webster, Boston Scientific, and Siemens, receiving consulting fees from Preventice, and holding equity Cardiac Design. All other authors have no conflicts of interest associated with the content of this manuscript., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Background: Lower neighborhood median household income (nMHI) is associated with increased adverse outcomes in patients with atrial fibrillation (AF). However, its effect on mortality is yet unknown., Methods: Data from the regional United States (U.S.) electronic medical records database, Research Action for Health Network (REACHnet), was extracted for adult patients with AF at Tulane Medical Center over 10 years. Annual nMHI & neighborhood high school graduation (HSG) data was collected from the US Census bureau. Only African Americans (AA) and Caucasians (CC) who had socioeconomic data were included. Low nMHI and low HSG were defined as ≤$25,000 & <90% respectively. High nMHI and HSG were defined as >$50,000 & ≥90% respectively. Primary endpoints were all cause and cardiovascular (CV) mortality. Cox-proportional hazard ratios were used to evaluate the endpoints., Results: We included 4616 patients diagnosed with AF. During a median follow up of 4.6 years, 434 patients died of which 32.7% patients had CV mortality. There was a stepwise decrease in incidence of both all-cause and CV mortality as nMHI increased. Patients with low nMHI had the greatest risk of all-cause mortality (HR 1.9, C.I. 1.2-3.2, P 0.004). The association between low nMHI and all-cause mortality persisted after adjusting for age, sex, race, HSG and stroke risk factors using CHA 2 DS 2 VASC, delta CHA 2 DS 2 VASC scores and oral anticoagulant use. CV mortality followed a similar trend as all-cause mortality, however, this association was not significant after adjusting for the above variables. Apart from low nMHI, CHA 2 DS 2 VASC delta CHA 2 DS 2 VASC were statistically significant independent predictors of both all-cause and CV mortality., Conclusion: Low nMHI is an independent risk factor for all cause and CV mortality in AF. Higher burden of co-morbidities is the driving force behind this disparity. Future studies should evaluate the role of educational and therapeutic intervention in these populations to reduce mortality., Competing Interests: Declaration of Competing Interest Dr. Marrouche reports consulting fees from Abbott, Biotronik, Wavelet Health, Cardiac Design, Medtronic, Preventice, Vytronus, Biosense Webster, Marrek Inc., and Boston Scientific; research funding from Abbott, Boston Scientific, GE Healthcare, Siemens, Biotronik, Vytronus, and Biosense Webster; ownership interest in Marrek Inc. and Cardiac Designs; contracted research with Biosense Webster, Medtronic, St. Jude Medical, and Boston Scientific; and reports consulting fees from Biotronik and Preventice. The remaining authors have no disclosures to report., (Published by Elsevier Inc.)

Background: Patients with COVID-19 have increased sleep disturbances and decreased sleep quality during and after the infection. The current published literature focuses mainly on qualitative analyses based on surveys and subjective measurements rather than quantitative data., Objective: In this paper, we assessed the long-term effects of COVID-19 through sleep patterns from continuous signals collected via wearable wristbands., Methods: Patients with a history of COVID-19 were compared to a control arm of individuals who never had COVID-19. Baseline demographics were collected for each subject. Linear correlations among the mean duration of each sleep phase and the mean daily biometrics were performed. The average duration for each subject's total sleep time and sleep phases per night was calculated and compared between the 2 groups., Results: This study includes 122 patients with COVID-19 and 588 controls (N=710). Total sleep time was positively correlated with respiratory rate (RR) and oxygen saturation (SpO 2 ). Increased awake sleep phase was correlated with increased heart rate, decreased RR, heart rate variability (HRV), and SpO 2 . Increased light sleep time was correlated with increased RR and SpO 2 in the group with COVID-19. Deep sleep duration was correlated with decreased heart rate as well as increased RR and SpO 2 . When comparing different sleep phases, patients with long COVID-19 had decreased light sleep (244, SD 67 vs 258, SD 67; P=.003) and decreased deep sleep time (123, SD 66 vs 128, SD 58; P=.02)., Conclusions: Regardless of the demographic background and symptom levels, patients with a history of COVID-19 infection demonstrated altered sleep architecture when compared to matched controls. The sleep of patients with COVID-19 was characterized by decreased total sleep and deep sleep., (©Mario Mekhael, Chan Ho Lim, Abdel Hadi El Hajjar, Charbel Noujaim, Christopher Pottle, Noor Makan, Lilas Dagher, Yichi Zhang, Nour Chouman, Dan L Li, Tarek Ayoub, Nassir Marrouche. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 05.07.2022.)

Background: Interlesion gaps and transmurality of lesions after catheter ablation can precipitate suboptimal efficacy in preventing arrhythmias., Aims: We aim to assess predictors of acute transmural lesion formation and the interlesion distance threshold for creating a continuous, chronic scar after ventricular ablation., Materials and Methods: Ablation procedures were performed on 7 canines followed by late gadolinium enhancement MRI (LGE-MRI). Transmurality of lesions was assessed by 2 independent operators. Ablation parameters such as duration (s), power (W), temperature (C), contact force (CF) (g), were collected for each ablation point. After 7-12 weeks, LGE-MRI was performed, followed by euthanasia, and heart excision. Some lesions were created in pair. Lesion pairs were spaced 7-21 mm apart as measured by Electroanatomic mapping (EAM), with different operating parameters (power 35 or 50W, duration of energy delivery 10, 20 or 30s and contact force of 10g or above). We performed a logistic regression analysis to determine predictors of transmural lesion formation., Results: Eighty-one radiofrequency ablation were performed in total [33 in the Left ventricle (LV) and 48 in the Right ventricle (RV)]. Higher CF was a significant predictor of transmural lesion formation (β = 0.15, OR = 1.16, 95% CI [1.03 - 1.3], p = 0.01), and lesions delivered in the RV were more frequently transmural than lesions delivered in the LV (β = -2.43, OR = 0.09, 95%CI [0.02 - 0.34], p < 0.001). For the paired analysis, thirty-eight lesions were created contiguously: fourteen connected lesions and twenty-four unconnected lesions. EAM distance was significantly larger in unconnected lesions than connected lesions (16.17 ± 0.92 mm vs. 11.51 ± 0.68 mm, respectively, p < 0.05). We concluded that an interlesion distance of less than 10 mm is required to prevent gap formation. Average volumes in unconnected lesions ( n = 24) at the acute and chronic stages were 0.55 ± 0.11 cm 3 and 0.20 ± 0.02 cm 3 , respectively. On average, lesion volumes were 64% ( p < 0.05) smaller at the chronic stage compared to the acute stage. Among connected lesions ( n = 14), we observed a volume of 1.19 ± 0.8 cm 3 and 0.39 ± 0.15 cm 3 at the acute and chronic stages, respectively. These connected lesions reduced in volume by 67% on average., Conclusion: To create contiguous scars on the ventricular endocardial surface, paired lesions should be spaced less than ten millimeters apart. Higher contact force should be used in ventricular ablation to create transmural lesions., Competing Interests: NM reports receiving research grant support from Sanofi, Biosense Webster, Boston Scientific, Abbot, and Janssen; provides consulting services to Biosense Webster and Atricure; and received lecture honorarium from BMS, Biotronic, and Sanofi. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 El Hajjar, Mekhael, Huang, Noujaim, Zhang, Kholmovski, Ayoub, Lim and Marrouche.)