Impact of obesity on atrial fibrillation ablation

Central illustration. Summary of strategies to improve atrial fibrillation (AF) ablation outcomes in obese patients. BMI: body mass index; BS: bariatric surgery; CT: computed tomography; CV: cardiovascular; EAM: electro-anatomical mapping system; EAT: epicardial adipose tissue; MRI: magnetic resonance imaging; NOAC: non-vitamin K antagonist oral anticoagulant; PAF: paroxysmal atrial fibrillation; TOE: transoesophageal echocardiography; TTE: transthoracic echocardiography; US: ultrasound; VKA: vitamin K antagonist.

     

The impact of malnutrition on atrial fibrillation recurrence post ablation

Background and aimsBoth malnutrition and atrial fibrillation (AF) are the major health problems in modern society. Only a few studies focused on the relationship between malnutrition and recurrence of atrial arrhythmias post AF ablation (AF recurrence), which used body mass index (BMI) as nutrition assessment tool. However, BMI can't credibly reflect body composition and has limitation in patients with water-sodium retention. In this study, we used controlling nutritional status score (CONUT score) and geriatric nutritional risk index (GNRI) to identify the malnutrition patients and explored the effect of malnutrition on AF recurrence.Methods and resultsThis retrospective study included 246 patients who underwent AF ablation. During a median 11-month follow-up, 77 patients (31.3%) experienced AF recurrence. The recurrence group had higher CONUT score (2.3 ± 1.5 vs. 0.9 ± 1.0, P < 0.001) and lower GNRI (99.9 ± 7.6 vs. 103.9 ± 5.6, P < 0.001). After balancing the traditional risk factors, both CONUT score (OR: 2.614, 95%CI: 1.831–3.731, P < 0.001) and GNRI (OR: 0.884, 95%CI: 0.828–0.944, P < 0.001) were the independent predictors for AF recurrence. Pre-ablation CONUT score ≥1 and GNRI≥95.66 are indicative of AF recurrence. Adding CONUT score or GNRI to the base prediction model for AF recurrence significantly improved the discrimination and calibration. However, adding BMI to the base prediction model did not improve the model performance.ConclusionsCONUT score and GNRI are ideal tools to evaluate the nutrition status of AF patients. Undernourished patients are more likely to suffer from AF recurrence. Improving nutrition status may be a potential target for reducing the postoperative recurrence rate.     

Low vitamin D levels predict left atrial thrombus in nonvalvular atrial fibrillation

Background and aimsWe determined the association between left atrial (LA) thrombus occurrence and a non-classic risk marker, plasma levels of vitamin D, in atrial fibrillation (AF) patients on continuous non-vitamin K antagonist oral anticoagulant (NOAC) therapy for ≥4 weeks. Low levels of plasma 25-hydroxy vitamin D (25-OHD) are predictive of fatal stroke. Vitamin D has anticoagulant effects on the coagulation cascade, which are indirectly targeted by NOAC therapy. The impact of plasma levels of vitamin D on the rate of LA thrombus detected by transesophageal echocardiography (TEE) in AF patients is unknown.Methods and resultsWe enrolled 201 (133 female) AF patients who were using continuous NOAC therapy for ≥4 weeks. All patients underwent transthoracic and TEE examination. Serum concentrations of 25-OHD, C-reactive protein (CRP) levels, CHA₂DS₂-VASc scores and parameters, LA size, and left ventricle ejection fraction (LVEF) were examined before the TEE procedure. LA thrombus occurrence was independently associated with serum levels of 25-OHD (OR: 0.884; 95% CI: 0.839–0.932; P < 0.001), LA diameter (OR: 1.120; 95% CI: 1.038–1.209; P = 0.003), and LVEF(OR: 0.944; 95% CI: 0.896–0.995; P = 0.032). Dense spontaneous echo contrast (SEC) presence was also inversely associated with 25-OHD concentrations.ConclusionsLow 25-OHD levels, as a non-classic risk factor, were independently and significantly associated with dense SEC and LA thrombus occurrence in AF patients under NOAC therapy, as well as LA enlargement and decreased LVEF. Further large-scale studies are needed to explain the role of vitamin D deficiency, or efficacy of replacement, on LA thrombus occurrence.     

Comparative non-persistence in the first year of treatment with oral anticoagulants in patients with atrial fibrillation: A French comprehensive nationwide study

BackgroundDirect oral anticoagulants (DOACs) were developed as an alternative to vitamin K antagonists (VKAs) and are commonly used for stroke prevention in patients with non-valvular atrial fibrillation (NVAF). Unlike VKAs, DOACs do not require Internal Normalized Ratio (INR) monitoring, but regular intake is as important for effective anticoagulation.ObjectivesThis study examined treatment persistence among patients receiving oral anticoagulants (OACs) for NVAF.MethodsWithin the French healthcare claims database (SNDS), we assessed and compared the rates of non-persistence (≥ 30-day treatment gap) among patients with NVAF initiating an OAC between January 2014 and December 2016. The time-to-event of non-persistence was computed and plotted using a cumulative incidence function accounting for the competing risk of mortality. After adjusting on confounding factors, the risk for non-persistence was compared between apixaban and each other OACs using a Cox proportional hazard model, or Fine and Gray models.ResultsIn a cohort of 321,501 OAC-naive patients with NVAF, the cumulative incidence of non-persistence at 12 months considering competing risk was 44.3%, 31.0%, 41.3% and 46.8% for VKAs, apixaban, rivaroxaban and dabigatran, respectively. Median therapy duration before non-persistence ranged between 70 and 121 days. Non-persistence was lower with apixaban compared with VKAs (HR = 0.63, 95%CI = [0.62–0.64]), rivaroxaban (HR = 0.71, 95%CI = [0.70–0.73]), and dabigatran (HR = 0.60, 95%CI = [0.59–0.62]).ConclusionsIn this nationwide observational study, non-persistence rates of oral anticoagulant treatment were high in patients treated for NVAF. Apixaban-treated patients seem to experience lowest discontinuation rates 12 months after treatment initiation compared to patients treated with any other OAC.     

Clinical validation of an artificial intelligence algorithm offering cross-platform detection of atrial fibrillation using smart device electrocardiograms

BackgroundSeveral smart devices are able to detect atrial fibrillation automatically by recording a single-lead electrocardiogram, and have created a work overload at the hospital level as a result of the need for over-reads by physicians.AimTo compare the atrial fibrillation detection performances of the manufacturers’ algorithms of five smart devices and a novel deep neural network-based algorithm.MethodsWe compared the rate of inconclusive tracings and the diagnostic accuracy for the detection of atrial fibrillation between the manufacturers’ algorithms and the deep neural network-based algorithm on five smart devices, using a physician-interpreted 12-lead electrocardiogram as the reference standard.ResultsOf the 117 patients (27% female, median age 65 years, atrial fibrillation present at time of recording in 30%) included in the final analysis (resulting in 585 analyzed single-lead electrocardiogram tracings), the deep neural network-based algorithm exhibited a higher conclusive rate relative to the manufacturer algorithm for all five models: 98% vs. 84% for Apple; 99% vs. 81% for Fitbit; 96% vs. 77% for AliveCor; 99% vs. 85% for Samsung; and 97% vs. 74% for Withings (P < 0.01, for each model). When applying our deep neural network-based algorithm, sensitivity and specificity to correctly identify atrial fibrillation were not significantly different for all assessed smart devices.ConclusionIn this clinical validation, the deep neural network-based algorithm significantly reduced the number of tracings labeled inconclusive, while demonstrating similarly high diagnostic accuracy for the detection of atrial fibrillation, thereby providing a possible solution to the data surge created by these smart devices.     

Thromboembolic events in atrial fibrillation: Different level of risk and pattern between peripheral artery disease and coronary artery disease

A. Clinical outcomes (ischaemic stroke, ischaemic stroke/systemic thromboembolism and systemic thromboembolism) among patients with atrial fibrillation (AF) without coronary artery disease (CAD) or peripheral artery disease (PAD). B. Clinical outcomes among patients with AF and only CAD. C. Clinical outcomes among patients with AF and only PAD. D. Clinical outcomes among patients with AF and both CAD and PAD.