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Ultra-high-frequency ECG quantifies residual electrical dyssynchrony during left bundle branch area pacing in patients with wide QRS: a paired within-patient study.

BACKGROUND: Left bundle branch area pacing (LBBAP) may restore a more physiological pattern of ventricular activation in patients with conduction delay; however, QRS narrowing alone may incompletely characterize electrical resynchronization. Ultra-high-frequency ECG (UHF-ECG) provides quantitative markers of ventricular activation timing and dyssynchrony. OBJECTIVE: To quantify paired OFF-to-ON changes in conventional ECG and UHF-ECG metrics during LBBAP in patients with baseline wide QRS and to assess the relationship between paced R-wave peak time (RWPT) and residual UHF-ECG dyssynchrony. METHODS: In this prospective single-center paired study, 21 patients with bradycardia and baseline wide QRS underwent standard ECG and UHF-ECG assessment during intrinsic rhythm (pacing OFF) and during LBBAP (pacing ON). Endpoints included QRS duration, signed VED16, absolute VED16 (|VED16|), mean ventricular delay (meanVD), and a clinically interpretable distance-to-normal metric defined as dist&#xa0;=&#xa0;max(|VED16|-20, 0). Paired changes were summarized as medians with bootstrap 95% confidence intervals and tested using the Wilcoxon signed-rank test. Associations between paced RWPT and residual dyssynchrony during pacing were evaluated using Pearson and Spearman correlation coefficients. RESULTS: LBBAP significantly narrowed QRS duration from 136.8 [130.2-153.6] ms during intrinsic rhythm to 116.0 [107.8-125.6] ms during pacing (median &#x394; -21.0&#xa0;ms; 95% CI -33.9 to -18.6; p&#xa0;<&#xa0;0.001). Signed VED16 did not change significantly (median &#x394; 0.4&#xa0;ms; p&#xa0;=&#xa0;1.000), consistent with the mixed conduction-phenotype composition of the cohort. In contrast, severity-oriented UHF-ECG endpoints improved: |VED16| decreased numerically (median &#x394; -5.2&#xa0;ms; p&#xa0;=&#xa0;0.070), whereas dist decreased significantly (median &#x394; -0.7&#xa0;ms; 95% CI -14.4 to 0.0; p&#xa0;=&#xa0;0.015). The proportion of patients within the normal dyssynchrony band (|VED16|&#xa0;&#x2264;&#xa0;20&#xa0;ms) increased from 7/21 (33.3%) to 12/21 (57.1%). Median paced RWPT was 66.6 [58.6-74.6] ms, and shorter RWPT correlated with lower residual |VED16| during pacing (Pearson r&#xa0;=&#xa0;-0.45, p&#xa0;=&#xa0;0.038). CONCLUSIONS: In patients with baseline wide QRS, LBBAP produces marked QRS narrowing, whereas UHF-ECG provides complementary quantification of residual electrical dyssynchrony. Severity-oriented UHF-ECG endpoints, particularly a distance-to-normal metric, may offer an interpretable mechanistic framework beyond conventional ECG alone. Shorter paced RWPT was associated with lower residual dyssynchrony during pacing, supporting physiological coherence between procedural and high-resolution electrocardiographic markers.

Humans

Efficacy and Safety of Ultra-Low Starting Dose Febuxostat Titration in Male Patients With Primary Gout.

BACKGROUND: Since gout is a common metabolic arthritis caused by urate crystal deposition, urate-lowering therapy (ULT) is clearly indicated, but the initiation of ULT frequently causes paradoxical acute flares that in turn impair patient adherence. OBJECTIVE: This study sought to assess the effectiveness and safety of an ultra-low-dose initiation strategy for febuxostat (10&#x2009;mg/day) compared to the standard starting dose (20&#x2009;mg/day) in reducing initiation-related flares while maintaining long-term urate control. METHODS: 120 male patients with primary gout presenting with acute arthritis were randomly assigned to initiate febuxostat at 10&#x2009;mg/day (Group A) or 20&#x2009;mg/day (Group B), with protocol-mandated biweekly titration. The primary outcomes were gout flare frequency over 24&#x2009;weeks (assessed using Poisson regression), serum uric acid (SUA) target attainment, and the incidence of adverse events. RESULTS: Although both groups achieved comparable target SUA levels by week 24, Group A demonstrated a significantly lower overall flare incidence (36.7% vs. 70.0%; p&#x2009;<&#x2009;0.001), along with a greater percentage of flare-free patients (70.0% vs. 46.7%; p&#x2009;=&#x2009;0.016). Multivariable Poisson regression revealed that Group B had an approximately twofold higher risk of flares compared to Group A (Incidence Rate Ratio&#x2009;=&#x2009;1.95; p&#x2009;=&#x2009;0.012), with obese patients deriving the most pronounced benefit from the ultra-low-dose approach. To avert one additional flare, the calculated number needed to treat was 4.3. Additionally, the occurrence of clinically significant liver injury (ALT/AST >&#x2009;3&#xd7; ULN) was low in both groups, with 3.3% in Group A and 1.7% in Group B. Multivariable regression analysis confirmed that LDL-C is an independent predictor of ALT (&#x3b2;&#x2009;=&#x2009;12.90, p&#x2009;=&#x2009;0.009), while febuxostat dosage was not linked to hepatotoxicity. CONCLUSION: Initiating febuxostat at a dose of 10&#x2009;mg/day with gradual titration demonstrates a superior safety profile by effectively reducing early acute flares without compromising long-term urate control, which is particularly advantageous for high-risk cohorts, including obese patients.

Humans

Teaching Acute Coronary Syndrome High-Risk ECG Interpretation and Clinical Decision-Making Through FOAMed Videos and Podcast Versus Print-Based Materials Among Emergency Care Providers: Randomized Controlled Mixed Methods Trial.

BACKGROUND: Accurate interpretation of high-risk acute coronary syndrome (ACS) electrocardiograms (ECGs) is essential for early diagnosis and timely reperfusion, yet substantial deficits persist across health care professions. Digital self-learning formats such as FOAMed (Free Open Access Medical Education) are widely used, but their effectiveness has rarely been evaluated for complex, high-risk ACS ECG patterns. Existing ECG education studies often focus on students or single professional groups and established ST-segment elevation myocardial infarction (STEMI) criteria, leaving newer guideline-recognized STEMI equivalents, selected emerging occlusion myocardial infarction (OMI)-related patterns, and interprofessional emergency care underrepresented. OBJECTIVE: This study aimed to compare the effectiveness of FOAMed podcast and videos versus traditional print-based materials for teaching high-risk ACS ECG patterns and related clinical decision-making in emergency providers. METHODS: We conducted a prospective, interprofessional, controlled mixed methods trial across 5 training sites in Germany. Paramedics, prehospital emergency physicians, and emergency department clinicians received either a FOAMed multimedia module or print-based materials through concealed allocation; deviations from the intended 1:1 ratio resulted from participant no-shows. The intervention consisted of a 30-minute supervised self-learning session. In total, 103 participants were allocated to FOAMed (n=45) or print-based materials (n=58). Two coprimary outcomes were assessed: ECG interpretation accuracy and text-based ACS clinical decision-making. Secondary outcomes included subjective confidence, learning experience, and exploratory qualitative free-text responses. Outcome assessment was automated and blinded; mixed ANOVA was the primary analysis. The study was not prospectively registered because it assessed educational outcomes in health care professionals rather than patient health outcomes. RESULTS: All 103 participants completed the study. Both groups improved, with greater gains in the FOAMed group: ECG interpretation increased from 55% to 65.5% and text-based ACS clinical decision-making from 45% to 68%, versus 57% to 60% and from 47% to 63%, respectively, in the print-based group. Effect sizes were &#x3b7;&#xb2;=0.055 for ECG interpretation and &#x3b7;&#xb2;=0.044 for clinical decision-making. Exploratory subgroup analyses provided no evidence of differential effects across age, gender, or professional background and were likely underpowered. Qualitative responses (46 and 37 entries) provided contextual insights into perceived clarity, engagement, and practical relevance supporting the quantitative findings. CONCLUSIONS: This study is innovative in directly comparing a curated FOAMed multimedia module with selected print-based materials in an interprofessional emergency care population. It differs from existing research by focusing on subtle, emerging ischemic patterns and evaluating realistic, time-limited self-learning formats. The findings provide evidence that curated FOAMed resources can produce greater short-term improvements in ECG interpretation and text-based ACS clinical decision-making than traditional print-based materials in this setting. Although implications for clinical performance remain hypothetical, concise, high-quality digital modules may represent a practical supplement to structured continuing education in emergency care.

Humans

Ultra-high-field 7T MRI reveals neural abnormalities of attention networks in relation to cognitive impairment in hypertension.

Hypertension is a significant risk factor for cognitive impairment (CI), yet the corresponding neural network abnormalities remain underexplored. In this study, we examined the associations among global and domain-specific cognitive dysfunction, neuroimaging measures, and blood pressure in a subgroup of hypertensive patients with CI (N&#xa0;=&#xa0;41) from a randomized controlled trial who underwent ultra-high-field 7&#xa0;T MRI. Structural atrophy related to CI was localized to regions overlapping the attention networks. Both whole-brain and within-network dysfunction of the attention networks were associated with worse global cognitive performance. Notably, hyperconnectivity within key attention network hubs, including the right anterior insula and posterior intraparietal sulcus, was associated with declined processing speed in hypertensive patients, mediating the association between pulse pressure and processing speed. These findings provide new insights into the neural pathophysiology of hypertension-related CI and suggest potential network-based targets for intervention.

Magnetic Resonance Imaging

Effects of aerosol aging on composition and light-absorbance of nitrogen-containing organic compounds: Evidences from ultra-high-resolution mass spectrometry analysis.

Nitrogen-containing organic compounds (NOCs) are key components of particulate matter (PM), but their compositional evolution and light-absorbing properties during atmospheric aging remain poorly understood. In this study, ultra-high-performance liquid chromatography coupled with Orbitrap mass spectrometry was used to semi-quantitatively analyze 59 PM1 samples collected in Shanghai. NOCs accounted for 31 % and 64 % of the detected species in negative (ESI-) and positive (ESI+) ionization modes, respectively. Atmospheric aging significantly reduced the molecular diversity of polar organics, with both the number and mass concentration percentages of CHON- compounds showing significant negative correlations with aging degree. Van Krevelen analysis demonstrated a decrease in the number of carboxylic-rich alicyclic molecules and their CHON- contributions during the aging process (from 37.7 % in fresh samples to 21.2 % in aged samples). CHN+ compounds, a major NOCs group in ESI+ mode, also decreased with aging. Correlation analyses involving the Bep/(Bep+Bap) ratio, relative humidity, and mass absorption efficiency at 365 nm revealed a decline in light absorption capacity with aging, suggesting aqueous-phase oxidation as a dominant aging mechanism. CHON- and CHN+ compounds were identified as the principal light-absorbing constituents in PM1. This work provides new insights into the aging-induced transformations of NOCs in urban PM1, and their changing role in light absorption, highlighting the need for further investigation of the aging mechanisms of NOCs.

Aerosols

Reliability-aware hierarchical learning for Chagas disease screening from 12-lead ECGs: tackling label uncertainty and class imbalance.

Objective.Chagas disease, a neglected tropical disease (NTD) with significant cardiovascular impact, remains underdiagnosed in resource-limited regions. Electrocardiogram (ECG) screening offers a low-cost tool for detecting cardiac involvement, yet algorithm development is challenged by label noise, data scarcity, and the latent nature of infection. This study proposes a robust ECG-based screening framework that explicitly addresses these constraints.Approach.We introduce aReliability-Aware Hierarchical Learningstrategy that calibrates supervision according to data provenance, prioritizing serology-confirmed labels over noisy self-reports. To mitigate data scarcity, we compare a specialized convolutional neural network (CNN) trained from scratch with a transfer learning approach based on a Spatio-Temporal ECG foundation Model (FM). Performance is evaluated across varying data scales, and the representation structure is analyzed to interpret model behavior.Main results.On the official hidden test set of the George B. Moody PhysioNet/Computing in Cardiology Challenge 2025, our approach achieved a Challenge Score of 0.163. We observe that while the specialized CNN performs competitively in data-rich regimes, the FM exhibits superior robustness in extreme low-resource settings. Furthermore, performance reaches a plateau imposed by underlying disease physiology. Bimodal score distributions suggest that models distinguish established cardiomyopathy from indeterminate infection, which remains electrophysiologically indistinguishable from healthy controls.Significance.These findings clarify both the potential and intrinsic limits of ECG-based AI screening for NTD-associated cardiac involvement. Reliability-aware supervision and data-efficient transfer learning provide a practical framework toward scalable and clinically meaningful ECG screening systems in resource-constrained environments.

Humans

Spatial proximity or vector orientation? Re-evaluating ECG interpretation in anterior myocardial infarction using cardiac magnetic resonance.

BACKGROUND: The electrocardiogram (ECG) is widely used to infer infarct location and extent in anterior myocardial infarction (MI), based on either anatomical lead proximity or vectorial orientation of ST-segment deviation. However, the validity of these approaches against direct imaging of myocardial injury remains uncertain. METHODS: In this prospective study, 105 patients with anterior MI underwent cardiac magnetic resonance (CMR) imaging 3-7&#xa0;days after presentation. Admission ECGs were analyzed using (1) conventional ECG localization categories, and (2) simplified frontal and horizontal ST-axis orientation. CMR-defined injury distribution was assessed using late gadolinium enhancement and myocardial edema imaging. RESULTS: Conventional ECG localization categories demonstrated no significant association with CMR-defined infarct distribution (P&#xa0;=&#xa0;0.24), with poor agreement (&#x3ba;&#xa0;=&#xa0;0.122) and substantial overlap across categories. Simplified ST-axis orientation showed modest and inconsistent associations with infarct location and did not meaningfully explain infarct size. In contrast, global ST-segment burden was associated with CMR-defined infarct size (&#x3a3;STE: standardized &#x3b2;&#xa0;=&#xa0;0.307, P&#xa0;=&#xa0;0.002; lead count: standardized &#x3b2;&#xa0;=&#xa0;0.267, P&#xa0;=&#xa0;0.007). CONCLUSIONS: In this selected cohort of reperfused LAD-related anterior STEMI patients undergoing early CMR, conventional ECG localization categories and simplified ST-axis orientation showed poor or inconsistent correspondence with CMR-defined infarct distribution, whereas global ST-segment burden showed a modest association with infarct size. These findings suggest that, in this cohort, the ECG may be better suited to reflect the extent of myocardial injury rather than its precise anatomical location.

Humans

First evaluation of a novel recombinant eCG molecule in ewes reveals a discrepancy between ovulatory response and pregnancy outcome.

This study evaluated the reproductive performance and clinical safety of a novel recombinant eCG (r-eCG) in ewes. Two weeks prior to study onset (Day 0: intravaginal progesterone device insertion), 45 ewes were randomly assigned to negative control (NC; no eCG; n&#x202f;=&#x202f;10), positive control (PC; 400IU commercial non-recombinant eCG; n&#x202f;=&#x202f;20), or treatment group (T; 400IU r-eCG; n&#x202f;=&#x202f;15). Ewes were inseminated with fresh-diluted semen (200&#x202f;&#xd7;&#x202f;106 sperm). Ultrasonography assessed follicle count/diameter (days 11, 13), ovulation (day 13), corpus luteum (CL) number/characteristics (day 20), and pregnancy (day 44). Serum progesterone was measured on day 20; Group T underwent clinical/hematological evaluations (days 0, 20, and 44). Estrus signs were more frequent (P&#x202f;<&#x202f;0.01) in T (100%) than NC (50%), while PC (85%) did not differ. Ovulation rates were similar between T (93%) and PC (95%), but higher than NC (50%; P&#x202f;<&#x202f;0.05). On day 13, largest follicle diameter did not differ (P&#x202f;>&#x202f;0.05) among groups; however, fewer follicles > 2&#x202f;mm occurred in PC than NC and T (P&#x202f;<&#x202f;0.05). CL number was higher in T than PC (2.0&#x202f;&#xb1;&#x202f;0.3 vs. 1.0&#x202f;&#xb1;&#x202f;0.0, P&#x202f;<&#x202f;0.01), while NC did not differ (1.0&#x202f;&#xb1;&#x202f;0.25). Conversely, pregnancy rate was higher (P&#x202f;<&#x202f;0.05) in PC (70%) than T (28.6%) and NC (20%). Among ovulated ewes, progesterone concentration and progesterone/CL ratio did not differ among groups (P&#x202f;=&#x202f;0.92 and P&#x202f;=&#x202f;0.08, respectively). No relevant r-eCG-related clinical or hematological alterations occurred. In conclusion, 400IU r-eCG effectively induces estrus and ovulation without adverse effects; however, the discrepancy between ovulatory response and pregnancy rate underscores the need for further study refinement to improve fertility.

Animals

Fundamentals of pacemakers ECG interpretation - part 2.

BACKGROUND: Modern pacemakers incorporate arrhythmia-response algorithms, ventricular pacing minimization protocols, and safety mechanisms that generate ECG patterns indistinguishable from pathological AV block, sensing malfunction, or device-mediated tachycardia. Failure to recognize these algorithm-driven signatures leads to unnecessary interventions, misdiagnosis, and inappropriate device reprogramming. This manuscript is the second in a two-part series on pacemaker ECG interpretation. METHODS: We conducted a narrative review of peer-reviewed literature and device-specific documentation on algorithm-driven ECG behavior, synthesizing evidence across arrhythmia recognition, upper rate physiology, ventricular pacing minimization, mode switching, safety mechanisms, and hysteresis algorithms. RESULTS: Pacemaker-mediated tachycardia produces regular paced wide-complex tachycardia locked at the upper tracking rate, initiated by any event with retrograde VA conduction. Ventricular tachycardia is identified by QRS morphology diverging from the known paced pattern, absent pacing spikes, and AV dissociation. Upper rate Wenckebach behavior mimics Mobitz type I AV block; 2:1 upper rate response mimics second-degree AV block. Ventricular pacing minimization algorithms produce isolated nonconducted P waves and prolonged AV intervals that simulate pathological conduction disease. Mode switching causes abrupt rate drops misidentified as output failure. Ventricular safety pacing generates a conspicuously short, fixed AV interval. Three discrete pacing artifacts reflect AV-sequential cardiac resynchronization therapy (CRT), ventricular safety pacing in CRT, or His-bundle pacing with backup RV output. Rate and AV hysteresis produce pauses and wandering AV intervals mimicking oversensing or Wenckebach periodicity. CONCLUSIONS: Recognizing algorithm-driven ECG patterns requires knowledge of device timing intervals and refractory periods, which lets clinicians distinguish programmed behavior from true malfunction or cardiac arrhythmia.

Humans

Second-Generation ELZA-sub400 Protocol: Individualized High-Fluence Cross-Linking for Ultra-Thin Keratoconus Corneas.

PURPOSE: To evaluate the safety and efficacy of a second-generation individualized corneal cross-linking (CXL) protocol (ELZA-sub400) using high-fluence UV-A irradiation in ultrathin ectatic corneas. DESIGN: Retrospective, single-center, consecutive interventional case series. METHODS: Twenty-nine eyes of 24 patients with progressive keratoconus or post-LASIK ectasia and a post-soak intraoperative thinnest stromal thickness <400 &#xb5;m were included. After epithelial removal and riboflavin soaking, continuous UV-A irradiation (365 nm) at 3 or 9 mW/cm&#xb2; was delivered with total fluence titrated up to 10 J/cm&#xb2; based on intraoperative ultrasound pachymetry and a previously published nomogram targeting an uncross-linked stromal margin of approximately 70 &#xb5;m above the endothelium. Outcomes were assessed at baseline and up to 12 months using corrected distance visual acuity (CDVA) and corneal parameters measured using Scheimpflug tomography and anterior segment OCT (AS-OCT) with Placido-based topography. The main outcome measure was the proportion of eyes without progression at 12 months, defined as <1.0 D increase in maximum keratometry (Kmax). Secondary outcomes included changes in CDVA, refraction, Kmax, stromal thickness, demarcation line depth, densitometry, and safety parameters. RESULTS: At 12 months, 22/29 eyes (76%; 95% CI, 57.9%-87.8%) met the nonprogression criterion. Mean change in Kmax was -0.77 &#xb1; 5.10 D (95% CI, -2.71 to 1.17; P = .418). Mean demarcation line-to-anterior stroma distance was 205 &#xb1; 64 &#xb5;m (95% CI, 180.7-229.3), and demarcation line-to-endothelium distance was 64 &#xb5;m (IQR, 49-152). All demarcation lines remained within the stromal layer; 15/29 eyes (51.7%) had a demarcation line located &#x2264;70 &#xb5;m from the endothelium. Median CDVA changed from 0.10 to 0.32 logMAR (P = .142). Minimum stromal thickness showed a median change of -4.0 &#xb5;m (P = .309). No significant change was observed in densitometry, and no eye developed deep stromal haze or endothelial decompensation. CONCLUSIONS: Second-generation ELZA-sub400 CXL halted ectasia progression in 76% of ultrathin corneas at 12 months and was associated with an acceptable short-term safety profile, including stromal-confined demarcation line formation and no observed endothelial decompensation. The numerical decline in spectacle CDVA observed in this severely affected cohort did not reach statistical significance but is clinically important and warrants confirmation in larger prospective studies.

Humans

A New Highly Concentrated Insulin Aspart AT278 (500&#x2009;U/mL) Demonstrates Ultra-Rapid Pharmacokinetic and Pharmacodynamic Properties in Type 2 Diabetes Regardless of BMI.

AIMS: To evaluate the pharmacokinetics, pharmacodynamics, and safety of a novel U500 insulin aspart formulation (AT278 [500&#x2009;U/mL]; AT278-U500) compared with standard concentration insulin aspart (InsAsp [100&#x2009;U/mL]; InsAsp-U100) and U500 human regular insulin (HumIns [500&#x2009;IU/mL]; HumIns-U500). MATERIALS AND METHODS: This single-centre, randomised, double-blind crossover 12-h euglycaemic clamp study was conducted in 41 overweight and obese people with type 2 diabetes (BMI 25.0-38.7&#x2009;kg/m2) receiving a single subcutaneous dose (0.5&#x2009;U/kg) of AT278-U500 and InsAsp-U100. HumIns-U500 was consecutively studied open label in a 24-h clamp. RESULTS: AT278-U500 exhibited a significantly faster insulin absorption than InsAsp-U100 and HumIns-U500 (t Early50%Cmax: 9&#x2009;min vs. 35&#x2009;min vs. 55&#x2009;min), leading to a significantly higher glucose-lowering effect within the first hour (AUCGIR,0-60min) compared with both InsAsp-U100 (treatment ratio 2.02 [95% CI 1.64; 2.50]) and HumIns-U500 (3.91 [2.89; 5.27]). When divided by median BMI (29.7&#x2009;kg/m2), AUCGIR,0-60min was significantly higher with AT278-U500 in both the low-BMI and high-BMI subgroup compared to InsAsp-U100. Linear regression showed a significant inverse relationship between BMI and AUCGIR,0-60min for InsAsp-U100 (slope -0.142, p&#x2009;<&#x2009;0.0001), whereas AT278-U500 showed no such relationship. Overall insulin exposure was similar for AT278-U500 and InsAsp-U100, while overall glucose-lowering effect was comparable across all three treatments. CONCLUSIONS: AT278-U500 maintains its ultra-rapid onset characteristics independent of BMI, representing the first ultra-rapid U500 option for prandial dosing in insulin-resistant people with type 2 diabetes requiring high-dose therapy. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT05754424.

Humans

Reliability of resting heart rate measurements in atrial fibrillation.

BACKGROUND: Heart rate (HR) control in atrial fibrillation (AF) is commonly guided by resting HR measurements, usually with 12&#x2011;lead ECG or in-office pulse palpation. OBJECTIVES: We aimed to assess the reliability of resting HR measurements in AF patients with long-term ambulatory ECG and activity monitoring. METHODS: We included patients who had recorded a full-disclosure ambulatory ECG with a mobile cardiac telemetry device equipped with an accelerometer (PocketECG, MEDICALgorithmics, Poland), with at least 95% AF. Resting HR samples (&#x2264;20 per individual/day) were collected as 10-s daytime (8&#xa0;am to 8&#xa0;pm) measurements after &#x2265;10&#xa0;min of rest. These samples were compared to each individual's mean daytime resting HR. RESULTS: In 832 patients (median age 77 (interquartile range (IQR) 69-83) years, 42% women) with a median registration duration of 13&#xa0;days (IQR 7-22), the population mean daytime resting HR was 85 (&#xb1;15) beats per minute (bpm). A single resting HR differed from the mean daytime resting HR by a mean of &#xb1;10.4% (IQR 3.6-14.4%). When the mean daytime resting HR was &#x2265;110&#xa0;bpm, 29% of resting HR samples were&#xa0;<&#xa0;110&#xa0;bpm, and when the mean daytime resting HR was 80-109&#xa0;bpm,11% of samples were&#xa0;&#x2265;&#xa0;110&#xa0;bpm. Resting HR measurement variability decreased to 5.3% (IQR 1.9-7.5%) when four resting HR samples were averaged. CONCLUSION: In patients with AF, a single resting HR measurement often differs substantially from the mean daytime resting HR. When a precise measurement is clinically relevant, repeated resting HR sampling or ambulatory monitoring can address this measurement imprecision.

Humans

Evaluation of the difference between automated and measured QTc intervals in children.

BACKGROUND: The corrected QT interval (QTc) is obtained through automated ECG computations or manual physician measurements. We hypothesized that differences exist in children between the measured and automated QTc intervals within and between Healthy and hypertrophic cardiomyopathy (HCM) subjects with greater differences for HCM due to structural abnormalities. METHODS: QT measurements - Bazett correction- automated (aQTc) and measured (mQTc), were extracted from the GE MUSE database for 385 Healthy pediatric (single ECG) and 208 HCM subjects (2 ECGs), stratified by age&#xa0;<&#xa0;12 and&#xa0;&#x2265;&#xa0;12&#xa0;yrs., sex, race, and ethnicity. QTc means (SD), automated and measured differences, and the difference of the differences of aQTc and mQTc were analyzed overall and by subgroups. All ECGs were read by one pediatric cardiologist with a second cardiologist reading a random subset of HCM ECGs to evaluate intraclass correlations and agreement. RESULTS: The mQTc intervals were shorter than aQTc intervals within Healthy (p&#xa0;<&#xa0;0.001) and within first HCM ECGs (p&#xa0;<&#xa0;0.001) with both aQTc and mQTc shorter in Healthy than HCM (p&#xa0;<&#xa0;0.001). The difference in these differences was significant overall using HCM ECG 1 but not HCM ECG 2. Healthy subject aQTc and mQTc intervals differed by age, sex, and race (p&#xa0;<&#xa0;0.002). HCM ECG 1 aQTc- mQTc intervals differed for age&#xa0;<&#xa0;12&#xa0;yrs., as well as by sex and race. HCM ECG 2 intervals differed only for age&#xa0;<&#xa0;12&#xa0;yrs. CONCLUSIONS: Compared to measured values, automated QTc values were significantly longer in both Healthy and HCM subjects. Automated measurements may overestimate the QTc.

Humans

Molecular Landscape and Advanced Diagnostic Technologies for BRAF Mutations in Cancer: From Quantitative PCR and ddPCR to CRISPR-Based Platforms.

BRAF mutations are key oncogenic alterations across multiple malignancies, including melanoma, thyroid carcinoma, colorectal cancer, non-small cell lung cancer, glioma, and hairy cell leukemia. The most prevalent variant, BRAF-V600E, induces constitutive activation of the MAPK signaling pathway, promoting tumor progression and influencing therapeutic responsiveness. Accurate detection of BRAF alterations is therefore essential for molecular classification, prognostic assessment, treatment selection, and resistance surveillance. This review summarizes the molecular heterogeneity of BRAF mutations and critically evaluates current diagnostic methodologies. Conventional approaches such as allele-specific PCR and Sanger sequencing are compared with advanced quantitative platforms, including high-resolution melting analysis, droplet digital PCR, and next-generation sequencing, with emphasis on analytical sensitivity, mutation coverage, and clinical applicability. Emerging technologies such as CRISPR-based assays, rolling circle amplification systems, and nanoparticle-based biosensors and point-of-care diagnostic platforms are also discussed for their potential to enhance ultra-sensitive detection, particularly in liquid biopsy settings. These emerging tools are highlighted for their potential to enable ultra-sensitive, rapid, and decentralized mutation detection, particularly in liquid biopsy settings. Key challenges, including intratumoral heterogeneity, low allele-frequency variants, FFPE-associated artifacts, and clonal evolution under therapeutic pressure, are examined within a translational framework. In addition, we examine critical barriers to clinical implementation, including standardization, cost, and global accessibility of molecular diagnostics, and outline potential solutions through scalable technologies and decentralized testing strategies. We propose that optimal BRAF testing requires a mutation subclass-informed and clinically integrated strategy combining comprehensive baseline profiling with longitudinal molecular monitoring. Future diagnostic paradigms will likely integrate multi-omics data and artificial intelligence (AI)-assisted interpretation to refine precision oncology implementation. Looking forward, we propose that optimal BRAF testing will require integration of multi-omics profiling with AI-assisted interpretation, enabling automated variant classification, real-time clinical decision support, and improved prediction of therapeutic response and resistance.

Humans

Misalignment between ultra-processed status and 'better for you' claims on premix alcohol products.

BACKGROUND: Premix alcohol products (also known as ready-to-drink beverages) are a rapidly expanding alcohol category and frequently marketed using 'better for you' claims (e.g., 'Low sugar', 'Natural'). Little is known about the extent to which these products are ultra-processed or whether marketing claims align with ultra-processed status. This study aimed to address this evidence gap by auditing ingredient disclosure on premix products, assessing the ultra-processed status of these products, and determining the prevalence of 'better for you' claims with a particular focus on claims relating to ultra-processed status. METHODS: 534 premix alcohol products sold in major Australian retail outlets were assessed. Products were evaluated for compliance with mandatory ingredient disclosure, classified according to ultra-processed status based on the presence of indicators of ultra-processing (additives and other industrial ingredients), and analysed to determine the prevalence and types of 'better for you' marketing claims. RESULTS: Only 79% of assessed products displayed an ingredients list. Among compliant products, 98% contained at least one additive or ingredient indicative of ultra-processing, most commonly flavours, carbonating agents, colours, and sweeteners. One-third (33%) of products containing an ultra-processing indicator displayed a claim suggesting naturalness or minimal processing. Substantially higher proportions of ultra-processed products than non-ultra-processed products carried health-related claims. DISCUSSION AND CONCLUSIONS: Premix beverages available in Australia are overwhelmingly ultra-processed, yet many are marketed in ways that may mislead consumers about their composition and healthfulness. Stronger regulatory oversight of ingredient disclosure and marketing claims in this sector is urgently needed to support informed consumer decision-making.

Alcoholic Beverages

Comparison between measured and synthesized posterior lead electrocardiograms during percutaneous coronary intervention-induced myocardial ischemia.

BACKGROUND: Posterior/inferolateral myocardial ischemia is frequently underrecognized on standard 12&#x2011;lead electrocardiography (ECG). Synthesized posterior leads derived from the standard 12&#x2011;lead ECG have been proposed as an alternative to directly measured posterior leads; however, their accuracy under controlled ischemic conditions has not been fully validated. METHODS: We prospectively enrolled 26 consecutive patients undergoing percutaneous coronary intervention (PCI) in whom simultaneously recorded measured and synthesized posterior lead ECGs (V7-V9) were obtained during balloon-induced myocardial ischemia. ST-segment deviation was measured at the ST junction (STJ), 40&#xa0;ms (ST1), and 80&#xa0;ms (ST2) thereafter. Agreement between measured and synthesized posterior leads was assessed using Pearson correlation and Bland-Altman analyses. As an exploratory patient-level analysis, diagnostic performance was compared with reciprocal anterior ST-segment depression (V1-V4). RESULTS: Strong correlations were observed between measured and synthesized posterior lead ST-segment deviations (V7: r&#xa0;=&#xa0;0.89; V8: r&#xa0;=&#xa0;0.86; V9: r&#xa0;=&#xa0;0.83; all P&#xa0;<&#xa0;0.001). Bland-Altman analysis demonstrated minimal systematic bias (within &#xb1;0.004&#xa0;mV) and narrow limits of agreement. Synthesized posterior leads showed higher diagnostic performance than reciprocal anterior ST-segment depression (AUC 0.917 vs. 0.708), although the difference was not statistically significant (DeLong test, P&#xa0;=&#xa0;0.197). Using a 0.05&#xa0;mV threshold, synthesized posterior leads demonstrated 83.3% sensitivity, 100% specificity, and 96.2% overall accuracy. CONCLUSIONS: Synthesized posterior leads closely reproduced measured posterior lead ST-segment deviations during percutaneous coronary intervention (PCI)-induced myocardial ischemia, supporting the technical validity of posterior lead reconstruction. Larger prospective studies are warranted to determine whether synthesized posterior leads provide incremental diagnostic value beyond careful interpretation of the standard 12&#x2011;lead ECG.

Humans

Electrocardiographic correlates of pacing induced cardiomyopathy and response to cardiac resynchronization therapy.

BACKGROUND: Chronic right ventricular (RV) pacing (RVP) causes pacing-induced cardiomyopathy (PICM) in only a small number of patients. We evaluated ECG correlates of (i) PICM and (ii) response to cardiac resynchronization therapy (CRT) upgrade. METHODS: We conducted a retrospective case-control study by including all CRT upgrades for PICM (LVEF <50%) at our center between 2014 and 2018. Controls were patients with &#x2265;5 ECGs all demonstrating RVP over &#x2265;2&#xa0;years and all echocardiographic LVEF &#x2265;50%. Root-summed-squared (3D) ECG was obtained from reconstructed vectorcardiographic X-Y-Z leads. Predictors of PICM and CRT response were assessed as area under ROC curve (AUC) for pre-CRT and &#x394; (post-CRT - pre-CRT) ECG intervals and QRS voltage-time-integrals (VTI). RESULTS: We included 104 patients with CRT upgrade for PICM (age 73.7&#xa0;&#xb1;&#xa0;10.5&#xa0;years, female 29.1%, QRS duration 167.8&#xa0;&#xb1;&#xa0;25.2&#xa0;ms, LVEF 28.8&#xa0;&#xb1;&#xa0;8.0%, &#x394;LVEF 13.8&#xa0;&#xb1;&#xa0;10.3%) and 178 controls without PICM (age 73.2&#xa0;&#xb1;&#xa0;14.9&#xa0;years, female 52.8%, QRS duration 144.0&#xa0;&#xb1;&#xa0;20.9&#xa0;ms, LVEF 56.7&#xa0;&#xb1;&#xa0;5.2%). PICM was best identified by VTIQRS-3D (AUC 0.851; VTIQRS-3D&#xa0;&#x2265;&#xa0;80 &#x3bc;Vs sensitivity 87.5%, specificity 63.5%), VTIQRS-Y (0.846), and QRS duration (0.775). CRT response (LVEF increase &#x2265;10% at 3-12&#xa0;months) occurred in 73/104 (70.2%) patients. Lack of CRT response was best predicted by longer pre-CRT QRS duration (AUC 0.640; QRS duration &#x2265;180&#xa0;ms sensitivity 45.2%, specificity 83.6%), and less &#x394;VTIQRS-3D (0.609) and &#x394;VTIQRS-X (0.608). CONCLUSION: In patients with chronic RVP, VTIQRS-3D&#xa0;&#x2265;&#xa0;80 &#x3bc;Vs can be used as a screening test for echocardiographic confirmation of PICM. RV-paced QRS duration >180&#xa0;ms, on the other hand, identifies those who may not respond to CRT upgrade.

Humans

Feasibility and efficacy of left bundle branch area pacing guided by modified chest lead 1.

BACKGROUND: Left bundle branch area pacing (LBBAP) typically requires 12&#x2011;lead electrocardiogram (ECG) measurements using an electrophysiology (EP) recording system. However, a simplified approach using modified chest lead 1 (MCL1) is potentially feasible. This study aimed to compare the success rate and pacing outcomes of LBBAP guided by MCL1 with those guided by the 12&#x2011;lead ECG using an EP recording system. METHODS: This retrospective, single-center study included patients with preserved left ventricular ejection fraction who underwent LBBAP for bradyarrhythmia. LBBAP was either guided by 12&#x2011;lead ECG using an EP recording system or by MCL1. In the MCL1 group, a follow-up examination with a 12&#x2011;lead ECG using an EP recording system was conducted within one week postoperatively. RESULTS: A total of 65 patients underwent LBBAP (EP recording system group: n&#xa0;=&#xa0;35; MCL1 group: n&#xa0;=&#xa0;30). The overall success rate of LBBAP was 84.6%, with no significant difference between groups (88.5% vs. 80.0%, p&#xa0;=&#xa0;0.49). No significant differences were observed in the paced QRS duration (140.4&#xa0;&#xb1;&#xa0;8.0 vs. 141.9&#xa0;&#xb1;&#xa0;13.1&#xa0;ms, p&#xa0;=&#xa0;0.54), V6-V1 interpeak interval (39.7&#xa0;&#xb1;&#xa0;16.5 vs. 38.3&#xa0;&#xb1;&#xa0;15.6&#xa0;ms, p&#xa0;=&#xa0;0.79), or V6 R-wave peak time (69.8&#xa0;&#xb1;&#xa0;12.3 vs. 71.5&#xa0;&#xb1;&#xa0;12.1&#xa0;ms, p&#xa0;=&#xa0;0.68). CONCLUSIONS: MCL1-guided LBBAP was feasible and achieved a high success rate, with outcomes comparable to those of conventional EP recording system-guided implantation. This simplified approach may reduce procedural complexity and may allow LBBAP implantation without the routine use of an EP recording system.

Humans