We appreciate the careful and critical reading of our work by Eltawil et al [...].
We appreciate the careful and critical reading of our work by Eltawil et al [...].
Low QRS voltage relative to left ventricle (LV) thickness is one of the red flag characteristics in the diagnosis of cardiac amyloidosis, and it can be measured by specific indexes. Few studies have clearly defined the diagnostic threshold of voltage indexes for light chain amyloidosis cardiomyopathy (AL-CA) patients and other patients with LV hypertrophy. This case-control study analyzed electrocardiograms and echocardiograms of patients with AL-CA, hypertrophic cardiomyopathy (HCM), and hypertension left ventricular hypertrophy (HTN-LVH) seen at a single university center from 2008 to 2022. Low QRS voltage and three different precordial voltage indexes were evaluated. Diagnostic thresholds for rule-in and rule-out were calculated for AL-CA against each control group. A single voltage-mass ratio based on cross-sectional area (CSA) exhibited most accurate diagnostic accuracy, and the value of ≤1.72 aids the rule-in of AL-CA against other causes of left ventricular hypertrophy, providing a positive predictive value (PPV) of 86% versus HCM and 75% versus HTN-LVH.
Fontan patients experience anatomical remodeling over time, yet the mechanisms driving these changes remain unclear. This study aimed to characterize full-route Fontan remodeling and evaluate whether observed morphological changes arise from somatic growth alone or from the combined influence of conduit properties, surgical design, thoracic anatomy, and mechanical forces. Five Fontan patients (four extracardiac, one lateral tunnel) underwent analysis using two MRI-derived 3D models obtained between 1 and 4 years apart. Directional displacement was assessed using 3D shape overlays, surface geometry was quantified using the Koenderink Shape Index (KSI), and patient-specific growth mapping estimated localized tissue dynamics. Statistical analyses included a one-sample t-test for mean anterior displacement, the Grubbs' test for outlier detection, and the Wilcoxon signed-rank test for KSI comparisons across time points. All patients exhibited anterior displacement of the Fontan route, with a mean shift of 0.29″ ± 0.33″ and one significant outlier (lateral tunnel, 0.87″). Four of five patients showed increased convexity over time. Growth mapping revealed minimal, heterogeneous native-tissue expansion, with localized growth up to 0.2 mm/year. Individual remodeling trajectories varied and did not consistently align with localized anterior growth, indicating that Fontan route remodeling is highly individualized and cannot be explained by somatic growth alone. This retrospective longitudinal case series study highlights the value of quantitative 3D geometric tools for assessing subtle Fontan route remodeling and supports the feasibility of growth-aware, patient-specific modeling frameworks in single-ventricle physiology.
Machine learning is increasingly applied to cardiovascular disease prediction yet reported performance metrics often appear implausibly high due to methodological errors. Recent work has reported nearly perfect predictive accuracy (≈99%) using a k-Nearest Neighbors (kNN) model on CDC heart-disease data. Such performance greatly exceeds typical BRFSS-based benchmarks and strongly indicates data leakage. In this commentary, we replicate and re-analyze the original workflow, showing that the authors applied the SMOTE-ENN resampling method prior to the train/test split, thereby allowing synthetic data generated from the full dataset to contaminate the test set. Combined with an excessively small neighborhood parameter (k = 2), this produced misleadingly high accuracy. It is noted that (1) with SMOTE-ENN performed globally, synthetic samples appear nearly identical to test points, leading to near-perfect classification, and (2) this kNN choice is unusually small for a dataset of this scale and further amplifies leakage bias. Correcting the workflow by restricting oversampling to the training data or using undersampling restores realistic results, reducing predictive accuracy to approximately 80%, confirming the inflation caused by pre-split resampling and aligning with literature norms. This case underscores the critical importance of rigorous validation, transparent reporting, and leakage-free pipelines in medical AI. We outline practical guidelines for avoiding such pitfalls and ensuring reproducible, realistic, and clinically reliable machine-learning studies.
For the past decade, cell-based therapies have been the focus of research to investigate their potential to treat ischemic heart disease. The translation to human clinical studies depends on the demonstration of therapeutic efficacy and safety, particularly when transplanted in the subacute and chronic post-MI phase. A number of studies were identified that reported the effect of hiPSC-CMs on cardiac outcomes when transplanted at least 7 days post-myocardial infarction. The mean sample size of the published studies was 30 (±17) animals with a mean follow-up duration of 51 (±37) days. hiPSC-CM transplantation enhanced systolic function through augmented myocardial contractility, decreased infarct size, attenuated ventricular remodeling, and enhanced angiogenesis in the infarct and border zones in both small and large animal models. This effect was enhanced by co-transplantation with cells of vascular or adipose origin and is associated with high expression of VEGF in most studies. Despite this effect, transplanted hiPSC-CMs were structurally immature with limited survival at the endpoint. Epicardial delivery was associated with better efficacy outcomes and lower rates of arrhythmia. No study reported teratoma formation or immune rejection. From the current literature, there appears to be no consensus on the extent to which hiPSC-CMs improved systolic function, nor the degree to which this arises directly from integration of the new myocardium or from a paracrine-mediated mechanism. The nature of this paracrine mechanism and ways to improve the maturity and survival of implanted cardiomyocytes are issues that have yet to be resolved. In summary, while therapeutic benefit from cell therapy is clear, further research is required to establish whether the key mechanisms require a cellular component.
Background: Stage B heart failure (SBHF) increases the risk of symptomatic HF. Current guideline criteria for SBHF lack sex and ethnic thresholding and cardiac magnetic resonance (CMR) imaging cut-offs. We aimed to assess the prevalence of SBHF in a large cohort of people with type 2 diabetes (T2D) and healthy controls and propose a refined CMR definition for SBHF.
Methods: Sex- and ethnic-specific thresholds for imaging criteria were derived from 373 healthy controls, who underwent CMR cine imaging. The current definition for SBHF and refined criteria was applied to our prospectively recruited and intensively phenotyped cohort of asymptomatic people with T2D and no evidence of cardiovascular disease. The prevalence of SBHF by different definitions was calculated and patient characteristics, including exercise capacity, were compared between those classified as Stage A vs. B HF. Finally, the refined criteria were also applied to the following two historical cohorts with symptomatic cardiovascular disease: severe aortic stenosis (AS n = 70) and HF with preserved ejection fraction (HFpEF n = 136).
Results: A total of 423 people with T2D and a subset of 102 healthy controls who underwent echocardiography were prospectively recruited. Current guideline criteria classified 91% of those with T2D and 69% of the healthy controls as SBHF, suggesting a lack of specificity. Applying derived sex- and ethnicity-specific thresholds, combining echo and CMR measures, the prevalence of SBHF was reduced to 30% in those with T2D. Using the refined definition, those with Stage B HF had lower exercise capacity than those with Stage A HF (percentage predicted maximal oxygen consumption 81 ± 16% vs. 91 ± 20%, p < 0.001). Applying the refined definition to symptomatic AS and HFpEF participants classified 89% and 85% with abnormal cardiac remodelling.
Conclusion: Current guideline criteria for SBHF are non-specific and likely of limited value in clinical practice. Refining these criteria with sex- and ethnic-specific thresholds may improve identification of those at risk of developing symptomatic disease. Further research is required to validate these criteria.
Background and objective: Evidence of percutaneous left atrial appendage closure (LAAC) and oral anticoagulants (OACs) in non-valvular atrial fibrillation (NVAF) patients with intermediate-to-borderline high stroke risk is scarce. We aimed to compare the efficacy and safety of these treatments in the latter clinical population.
Methods: This retrospective cohort study included NVAF patients with CHA2DS2-VA scores of 1-2 and used 1:1 propensity score matching (184 patients per group) to compare efficacy and safety outcomes. The primary efficacy outcome was a composite of stroke, transient ischemic attacks, systemic embolism, and cardiovascular death during follow-up. Adverse safety events were categorized into peri-procedure (LAAC group) and non-procedural (both groups) events.
Results: Over a mean follow-up of 48.93 ± 28.50 months, a total of 26 patients (7.07%) reached the primary composite efficacy endpoint. The LAAC group showed a significantly higher incidence of the efficacy endpoint compared to the OAC group (HR = 3.09; 95% CI 1.22-7.85; log-rank p = 0.01). Procedure-related events occurred in five LAAC patients (one contributing to primary endpoint), while non-procedural bleeding rates were similar (0.54% vs. 1.09%; p = 0.56). Subgroup analyses suggested concomitant ablation of NVAF in LAAC group did not significantly improve efficacy composite endpoints (HR = 0.47).
Conclusions: In NVAF patients with intermediate-to-high stroke risk, OACs were more effective than LAAC in preventing thromboembolic events, with comparable rates of clinically relevant bleeding.
Background: Atrial dilated cardiomyopathy (ADCM) related to homozygous Natriuretic Peptide Precursor A (NPPA) pathogenic variants is an exceptionally rare inherited atrial cardiomyopathy characterized by progressive atrial enlargement, supraventricular arrhythmias, and eventual atrial standstill. Case summary: We report the case of a 9-year-old girl identified through population genetic screening as a homozygous carrier of the NPPA c.449G>A (p.Arg150Gln) variant who subsequently developed symptomatic paroxysmal atrial fibrillation (AF) at the age of 18. Although baseline cardiac investigations were normal, her current evaluation shows biatrial enlargement with preserved ventricular function. She underwent radiofrequency pulmonary vein isolation; however, recurrent symptomatic AF persists, requiring ongoing antiarrhythmic therapy and long-term oral anticoagulation (CHA2DS2-VA: 0; HAS-BLED: 0). Notably, patients with NPPA-related ADCM have a markedly increased thromboembolic risk due to progressive atrial mechanical failure, and anticoagulation should therefore be considered irrespective of conventional clinical risk scores. Discussion and conclusions: This case highlights the importance of genetic testing in young patients with atrial fibrillation and no underlying structural heart disease. The early identification of NPPA-related atrial dilated cardiomyopathy may aid in risk stratification and guide rhythm and anticoagulation management. Expanding genetic screening in select individuals with isolated atrial fibrillation may facilitate earlier diagnosis in this exceptionally rare condition.
Despite the efficacy of catheter ablation in preventing recurrences of atrial fibrillation (AF), the reasons for its lack of success in some patients remain unknown. The aim of this study was to try to identify a new predictor of AF recurrence following catheter-based treatment. This prospective study enrolled a cohort of patients with AF. Based on the results of a one-year follow-up, patients were divided into two groups: Group 1 ("vein-dependent" AF)-patients who achieved a successful outcome after 1-2 catheter ablation procedures-and Group 2 ("non-vein-dependent" AF)-patients with confirmed complete pulmonary vein isolation (PVI) or with an identified "non-vein-dependent" AF substrate. Blood samples were collected prior to the procedure and biobanked. Initial proteomic profiling of the serum using protein microarrays identified several candidate proteins, whose elevated levels were subsequently confirmed by an enzyme-linked immunosorbent assay (ELISA). This article presents data on one such protein-TAG72. A comparison of TAG72 levels (%OD normalized units) between Group 1 ("vein-dependent" AF) and Group 2 ("non-vein-dependent" AF) revealed a statistically significant increase in the latter group (128.9 [98.2; 284.4] vs. 84.3 [73.8; 92.1], p < 0.001). These data provide the first evidence implicating TAG72 in the pathogenesis of AF.
Intravascular imaging (IVI) was introduced 35 years ago to assess coronary artery pathology and plaque vulnerability. However, from its first applications it became apparent that it can also be useful in percutaneous coronary intervention (PCI) planning and optimizing PCI results. In the early days of PCI, IVI was used to examine the efficacy of emerging endovascular devices and the vessel wall response to therapy, while in the drug-eluting stent (DES) era, IVI was used to guide DES implantation and assess final results post-intervention. The first studies assessing the role of IVI in guiding PCI with DES have failed to demonstrate a prognostic benefit for the use of IVI; however, more recent large-scale randomized trials have underscored its value in this setting. IVI, with its high resolution, allows optimal stent sizing, prompt identification and correction of common causes of stent failure, and it has been shown that it improves outcomes in complex procedures. This review summarizes the evidence supporting the role of IVI in PCI planning in DES era, synopsizes the studies that have highlighted the value of IVI in predicting stent failure, discusses the limitations of the first randomized trials that failed to demonstrate a prognostic benefit from its use, and presents the results of the more recent large-scale outcome studies that underscored its role in complex PCI planning.

