Aims : Presence of arrhythmogenic left atrial (LA) low-voltage substrate (LVS) is associated with reduced arthythmia freedom rates following pulmonary vein isolation (PVI) in persistent atrial fibrillation (AF). We hypothesized that LA-LVS modifies amplified sinus-P-wave (APW) characteristics, enabling identification of patients at risk for arrhythmia recurrences following PVI.Methods and results : Ninety-five patients with persistent AF underwent high-density (>1200 sites) voltage mapping in sinus rhythm. Left atrial low-voltage substrate (<0.5 and <1.0 mV) was quantified in a 10-segment LA model. Amplified sinus-P-wave-morphology and -duration were evaluated using digitized 12-lead electrocardiograms (40–80 mm/mV, 100–200 mm/s). 12-months arrhythmia freedom following circumferential PVI was assessed in 139 patients with persistent AF. Left atrial low-voltage substrate was most frequently (84%) found at the anteroseptal LA. Characteristic changes of APW were related to the localization and extent of LA-LVS. At an early stage, LA-LVS predominantly located to the LA-anteroseptum and was associated with APW-prolongation (≥150 ms). More extensive LA-LVS involved larger areas of LA-anteroseptum, leading to morphological changes of APW (biphasic positive–negative P-waves in inferior leads). Severe LA-LVS involved the LA-anteroseptum, roof and posterior LA, but spared the inferior LA, lateral LA, and LA appendage. In this advanced stage, widespread LVS at the posterior LA abolished the negative portion of P-wave in the inferior leads. The delayed activation of the lateral LA and LA appendage produced the late positive deflections in the anterolateral leads, resulting in the “late-terminal P”-pattern. Structured analysis of APW-duration and -morphology stratified patients to their individual extent of LA-LVS (Grade 1: mean LA-LVS 4.9 cm2 at <1.0 mV; Grade 2: 28.6 cm2; Grade 3: 42.3 cm2; P < 0.01). The diagnostic value of APW-duration for identification of LA-LVS was significantly superior to standard P-wave-amplification (c-statistic 0.945 vs. 0.647). Arrhythmia freedom following PVI differed significantly between APW-predicted grades of LA-LVS-severity [hazard ratio (HR) 2.38, 95% confidence interval (CI) 1.18–4.83; P = 0.015 for Grade 1 vs. Grade 2; HR 1.79, 95% CI 1.00–3.21, P = 0.049 for Grade 2 vs. Grade 3). Arrhythmia freedom 12 months after PVI was 77%, 53%, and 33% in Grades 1, 2 and 3, respectively.Conclusion : Localization and extent of LA-LVS modifies APW-morphology and -duration. Analysis of APW allows accurate prediction of LA-LVS and enables rapid and non-invasive estimation of arrhythmia freedom following PVI.

Electro-anatomical voltage, conduction velocity (CV) mapping, and late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) have been correlated with atrial cardiomyopathy (ACM). However, the comparability between these modalities remains unclear. This study aims to (i) compare pathological substrate extent and location between current modalities, (ii) establish spatial histograms in a cohort, (iii) develop a new estimated optimized image intensity threshold (EOIIT) for LGE-MRI identifying patients with ACM, (iv) predict rhythm outcome after pulmonary vein isolation (PVI) for persistent atrial fibrillation (AF). Thirty-six ablation-naive persistent AF patients underwent LGE-MRI and high-definition electro-anatomical mapping in sinus rhythm. Late gadolinium enhancement areas were classified using the UTAH, image intensity ratio (IIR >1.20), and new EOIIT method for comparison to low-voltage substrate (LVS) and slow conduction areas <0.2 m/s. Receiver operating characteristic analysis was used to determine LGE thresholds optimally matching LVS. Atrial cardiomyopathy was defined as LVS extent ≥5% of the left atrium (LA) surface at <0.5 mV. The degree and distribution of detected pathological substrate (percentage of individual LA surface are) varied significantly (P < 0.001) across the mapping modalities: 10% (interquartile range 0–14%) of the LA displayed LVS <0.5 mV vs. 7% (0–12%) slow conduction areas 1.20, with most discrepancies on the posterior LA. Optimized image intensity thresholds and each patient’s mean blood pool intensity correlated linearly (R² = 0.89, P < 0.001). Concordance between LGE-MRI-based and LVS-based ACM diagnosis improved with the novel EOIIT applied at the anterior LA [83% sensitivity, 79% specificity, area under the curve (AUC): 0.89] in comparison to the UTAH method (67% sensitivity, 75% specificity, AUC: 0.81) and IIR >1.20 (75% sensitivity, 62% specificity, AUC: 0.67). Discordances in detected pathological substrate exist between LVS, CV, and LGE-MRI in the LA, irrespective of the LGE detection method. The new EOIIT method improves concordance of LGE-MRI-based ACM diagnosis with LVS in ablation-naive AF patients but discrepancy remains particularly on the posterior wall. All methods may enable the prediction of rhythm outcomes after PVI in patients with persistent AF.

Thromboembolism and stroke are dreaded complications in atrial fibrillation (AF). Established risk stratification models identify susceptible patients, but their discriminative properties are poor. Atrial cardiomyopathy (ACM) is associated to thromboembolism and stroke in smaller studies, but the modalities used for ACM-diagnosis (MRI and endocardial mapping) are unsuitable for widespread population screening. We aimed to investigate an ECG-based diagnosis of ACM using amplified p-wave analysis (APWA) for stratification of thromboembolic risk and cardiovascular outcome. In this case–control study, ACM-staging was performed using APWA on digital 12-lead sinus rhythm-ECGs in patients with LAA-thrombus and a propensity-score-matched control-cohort. Left atrial contractile function and thrombi were evaluated by transesophageal echocardiography (TEE). Outcome for MACCE including death was assessed using official registries and structured phone interviews. Left-atrial appendage [LAA]-thrombi and appropriate sinus rhythm-ECGs for ACM-staging were found in 109 of 4086 patients that were matched 1:1 to control patients without thrombus (218 patients in total). Both cohorts were comparable regarding cardiovascular risk factors, anticoagulants and CHA2DS2-VASC-score. ACM-stages 1 to 3 (equivalent to no, moderate and extensive ACM) were found in 63 (57.8%), 36 (33.0%) and 10 (9.2%) of patients without and 3 (2.8%), 23 (21.1%) and 83 (76.1%) of patients with LAA-thrombi. Atrial contractile function decreased from ACM-stages 1 to 3 (LAA-flow velocities 38 ± 16 cm/s, 31 ± 15 cm/s and 21 ± 12 cm/s; p < 0.0001), while the likelihood for LAA-thrombus increased (2.8%, 21.1% and 76.1%, p < 0.001). Multivariable analysis confirmed an independent odds ratio for LAA-thrombus of 24.6 (p < 0.001) per ACM-stage. Two-year survival free of stroke/TIA, hospitalization for heart failure, myocardial infarction or all-cause death was strongly reduced in ACM-stage 3 (53.8%) compared to no or moderate ACM (82.8% and 84.7%, respectively; p < 0.0001). Electrocardiographic diagnosis of ACM identifies patients with atrial contractile dysfunction and atrial thrombi at risk for adverse cardiovascular outcomes and death.

Aims: Despite advances in interventional treatment strategies, atrial fibrillation (AF) remains associated with significant morbidity and mortality. Fibrotic atrial myopathy (FAM) is a main factor for adverse outcomes of AF-ablation, but complex to diagnose using current methods. We aimed to derive a scoring system based entirely on easily available clinical parameters to predict FAM and ablation-success in everyday care. Methods: In this multicenter, prospective study, a new risk stratification model termed AF-SCORE was derived in 220 patients undergoing high-density left-atrial(LA) voltage-mapping to quantify FAM. AF-SCORE was validated for FAM in an external mapping-validation cohort (n = 220) and for success following pulmonary vein isolation (PVI)-only (without adjunctive left- or right atrial ablations) in an external outcome-validation cohort (n = 518). Results: FAM was rare in patients < 60 years (5.4%), but increased with ageing and affected 40.4% (59/146) of patients ≥ 60 years. Sex and AF-phenotype had additional predictive value in older patients and remained associated with FAM in multivariate models (odds ratio [OR] 6.194, p < 0.0001 for ≥ 60 years; OR 2.863, p < 0.0001 for female sex; OR 41.309, p < 0.0001 for AF-persistency). Additional clinical or diagnostic variables did not improve the model. AF-SCORE (+ 1 point for age ≥ 60 years and additional points for female sex [+ 1] and AF-persistency [+ 2]) showed good discrimination to detect FAM (c-statistic 0.792) and predicted arrhythmia-freedom following PVI (74.3%, 54.7% and 45.5% for AF-SCORE ≤ 2, 3 and 4, respectively, and hazard ratio [HR] 1.994 for AF-SCORE = 3 and HR 2.866 for AF-SCORE = 4, p < 0.001). Conclusions: Age, sex and AF-phenotype are the main determinants for the development of FAM. A low AF-SCORE ≤ 2 is found in paroxysmal AF-patients of any age and younger patients with persistent AF irrespective of sex, and associated with favorable outcomes of PVI-only. Freedom from arrhythmia remains unsatisfactory with AF-SCORE ≥ 3 as found in older patients, particularly females, with persistent AF, and future studies investigating adjunctive atrial ablations to PVI-only should focus on these groups of patients. Graphical

Background and Aims: Lipoprotein apheresis (LA) is the only approved treatment for patients with elevated lipoprotein(a) [Lp(a)]. The Lp(a)FRONTIERS APHERESIS trial investigated whether pelacarsen reduces the need for LA in patients from Germany with elevated Lp(a) and established cardiovascular disease (CVD). Methods: Adult patients with Lp(a) levels >60 mg/dl who had undergone ≥35 LA sessions in the prior year were randomized to receive pelacarsen 80 mg or placebo every 4 weeks for 52 weeks. Weekly LA sessions were performed if the Lp(a) measurement from the prior visit was >60 mg/dL. The primary endpoint was the rate of performed LA sessions normalized to the weekly LA schedule (the number of actual LA sessions divided by the number of planned LA sessions during the 52-week period). Secondary endpoints were time to LA avoidance (for ≥24 consecutive weeks) and total LA avoidance from week 12 to week 52. Results: Fifty-one patients were randomized (mean age 61.7 years, mean Lp(a) at baseline 85.4 mg/dL, and mean 44.0 LA sessions in the past 12 months), with 25 of 26 (96.2%) in the pelacarsen arm and 23 of 25 (92.0%) in the placebo arm completing the study. Baseline characteristics were generally balanced between treatment arms. Pelacarsen reduced the mean rates of LA (0.16 vs 0.93 in placebo, odds ratio 0.006, 95% confidence interval [CI] 0.003, 0.013; P < .0001) and substantially increased the hazard of achieving LA avoidance (hazard ratio: 88.3; P = .0014; median time to achieve LA avoidance: 6.1 weeks) and total LA avoidance (odds ratio: 163.2; P = .0005). The placebo-adjusted Lp(a) change from baseline at week 52 was −72% (95% CI: −79%, −61%; P < .0001). Treatment emergent adverse events were similar between arms, except for mostly mild injection site erythema (pelacarsen 38.5%; placebo 0%). Conclusions: Pelacarsen is a highly effective and well-tolerated Lp(a)-targeted therapy that substantially reduces the need for LA in patients with elevated Lp(a) and established CVD. ClinicalTrials.gov, identifier: NCT05305664.