Daily Cardiology Research Analysis
Analyzed 122 papers and selected 3 impactful papers.
Summary
Analyzed 122 papers and selected 3 impactful articles.
Selected Articles
1. Ferroptosis promotes aortic stenosis through 5-lipoxygenase.
Across human valves, cells, mice, and population cohorts, the study identifies lipid peroxidation-driven ferroptosis centered on ALOX5–ACSL4 as a key mechanism of calcific aortic valve disease. Pharmacologic ALOX5 inhibition reduced valve thickening and improved hemodynamics in vivo, while arachidonic acid levels predicted valve calcification and incident aortic stenosis in SCAPIS and UK Biobank.
Impact: This work provides a mechanistic, druggable pathway for a disease lacking medical therapy and links it to population-level risk, supporting rapid translational trajectories.
Clinical Implications: ALOX5 inhibition and ferroptosis-modulating strategies merit evaluation as disease-modifying therapies for calcific aortic valve disease; arachidonic acid and ferroptosis biomarkers may enhance risk stratification.
Key Findings
- Intra-leaflet haemorrhage correlated with calcification and circulating ferroptosis markers in human valves.
- Single-cell and bulk transcriptomics pinpointed lipid peroxidation via ALOX5 as a dominant ferroptosis pathway in valves.
- Induced ferroptosis in human VICs triggered lipid peroxidation and calcification, reversible by targeting the ALOX5–ACSL4 axis.
- ALOX5 inhibition reduced valve thickness and improved hemodynamics in vivo.
- Higher arachidonic acid predicted aortic valve calcification (SCAPIS) and incident aortic stenosis (UK Biobank).
Methodological Strengths
- Multi-platform integration: bulk/single-cell omics, histology, human VICs, and two in vivo models.
- External validation in two large population cohorts (SCAPIS and UK Biobank).
Limitations
- Causality in humans remains inferential; interventional human data are lacking.
- Potential off-target or safety considerations of chronic ALOX5 inhibition were not addressed.
Future Directions: Early-phase clinical trials of ALOX5 inhibitors or ferroptosis modulators in CAVD; longitudinal validation of ferroptosis biomarkers and arachidonic acid for risk prediction.
BACKGROUND AND AIMS: Calcific aortic valve disease (CAVD) culminates in severe aortic stenosis, currently lacking pharmacological treatment. Intra-leaflet haemorrhage-induced iron overload promotes valvular ferroptosis. This study identifies a druggable ferroptosis pathway and validates its translational relevance across large-scale population cohorts. METHODS: Bulk- and single-cell transcriptomics, whole-mount histology, immunohistochemistry, and primary human valvular interstitial cell (VIC) models of 212 aortic valves from surgical patients were integrated for mechanistic insights. In vivo, valvular ferroptosis and thickness were assessed in a doxorubicin-induced ferroptosis mice model, and a wire injury model with ferroptosis inhibition was utilized to evaluate remodelling and haemodynamic obstruction. A total of 4874 participants of the Swedish CArdioPulmonary bioImage Study (SCAPIS) underwent cardiac computed tomography for aortic valve calcification determination and 273 550 individuals from the UK Biobank were followed for aortic stenosis incidence.
2. A Slc5a6-Deficient Mouse Model Reveals Metabolically Driven Cardiomyopathy with Therapeutic Potential for Vitamin-Based Intervention.
Loss of SLC5A6-mediated biotin and pantothenate transport causes a metabolically driven dilated cardiomyopathy with mitochondrial dysfunction and ECM remodeling. Cardiac-specific Slc5a6 knockout mice develop progressive failure that is fully prevented by preconception vitamin supplementation, mirroring better outcomes in an early-treated patient.
Impact: Identifies a treatable, mechanism-based cause of cardiomyopathy and demonstrates prevention by a low-risk vitamin strategy in vivo, informing precision medicine.
Clinical Implications: Consider SLC5A6 genetic testing in early-onset or familial DCM; prompt biotin/pantothenate supplementation—ideally preconception/early life—may prevent disease in at-risk genotypes; prospective trials are warranted.
Key Findings
- Two unrelated families with SLC5A6 mutations presented with early-onset dilated cardiomyopathy.
- Cardiac-specific Slc5a6 knockout mice showed progressive dysfunction, hypertrophy, fibrosis, and impaired CoA synthesis, leading to premature death.
- Proteomics at 8 weeks revealed early mitochondrial metabolic disruption and ECM upregulation before overt dysfunction.
- Preconception vitamin supplementation (biotin/pantothenate) prevented cardiac phenotype and preserved survival.
- Early-treated patient improved, whereas untreated patient required heart transplant.
Methodological Strengths
- Human genetics linked to a cardiac-specific knockout model enabling causality testing.
- Multimodal assessment (CMR, ECG, proteomics) and a rescue-by-supplementation experiment.
Limitations
- Human sample size is small (two families), limiting generalizability.
- Preventive effect was shown with preconception supplementation; efficacy when started later remains uncertain.
Future Directions: Design genotype-guided clinical trials to define optimal dosing/timing of vitamin supplementation; evaluate newborn screening and carrier counseling strategies.
The sodium-dependent multivitamin transporter, encoded by SLC5A6, mediates cellular uptake of biotin and pantothenic acid, essential cofactors for energy metabolism. We identified two families with SLC5A6 mutations presenting with early-onset dilated cardiomyopathy (DCM). To investigate the link between vitamin deficiency and cardiomyopathy, we generated a cardiac-specific SLC5A6 knockout (Slc5a6cKO) mouse model and evaluated the impact of vitamin supplementation. Slc5a6cKO mice developed progressive cardiac dysfunction, culminating in cardiac pathology and premature death at 26 weeks; earlier stages exhibited cardiomyocyte hypertrophy, fibrosis, impaired Coenzyme A synthesis, and metabolic imbalance, indicating progression toward cardiomyopathy. Cardiac magnetic resonance imaging and ECG confirmed progressive functional decline. Proteomic analysis revealed early mitochondrial metabolic disruption and extracellular matrix protein upregulation at 8 weeks, preceding overt cardiac dysfunction. Strikingly, vitamin supplementation from preconception onwards prevented the cardiac phenotype, preserving cardiac structure, function, morphology and survival. This paralleled the clinical outcome in one patient who received early vitamin treatment, compared to another who required a heart transplant without vitamin treatment. This study establishes a direct link between SLC5A6-mediated vitamin transport, mitochondrial function, and cardiac health. It highlights how vitamin deficiency contributes to cardiomyopathy pathogenesis and supports early vitamin supplementation as a potential therapeutic strategy for metabolic cardiomyopathies.
3. Diagnostic Yield of Cardiac CT to Detect Cardiac Thrombi in Patients With Acute Ischemic Stroke (AIS of HEARTS).
In 3919 AIS patients, acute cardiac CT identified intracardiac thrombi in 6.2% and outperformed transthoracic echocardiography in detectability. Cardiac thrombus presence was associated with higher mortality, supporting integration of cardiac CT into acute stroke pathways to refine etiologic work-up and management.
Impact: Demonstrates feasibility and superior yield of cardiac CT within time-sensitive stroke imaging, with direct implications for acute care workflows and secondary prevention decisions.
Clinical Implications: Centers may consider adding ECG-gated/non-gated cardiac CT to acute stroke imaging to identify thrombi that alter anticoagulation and procedural strategies; protocols must balance added time and radiation.
Key Findings
- Cardiac CT detected thrombi in 243 of 3919 AIS patients (6.2%).
- Compared with transthoracic echocardiography (n=1323), cardiac CT had a higher yield (OR 7.4, 95% CI 4.0–15.1).
- Implementation added scan time and radiation but was feasible within acute workflows.
- Presence of cardiac thrombus was associated with higher 90-day mortality, not higher stroke recurrence.
Methodological Strengths
- One-stage individual patient data meta-analysis of four prospective cohorts.
- Adjusted outcome analyses with comprehensive clinical covariates.
Limitations
- Observational design without randomization may introduce selection and imaging-protocol heterogeneity.
- Radiation dose and ECG-gating varied; cost-effectiveness not assessed.
Future Directions: Randomized or pragmatic studies to compare stroke workflows with vs. without cardiac CT; standardized protocols and cost-effectiveness analyses.
BACKGROUND: Cardiac computed tomography (CT) acquired during the acute stroke imaging protocol is an emerging modality to detect cardiac thrombi. We determined its yield in patients with acute ischemic stroke. METHODS: We performed a 1-stage individual patient data meta-analysis of 4 prospective observational cohorts (AIS of HEARTS [Acute Ischemic Stroke of Heart-Related Embolic Sources Detected on Acute Cardiac CT Scans]), including patients with acute ischemic stroke who underwent ECG-gated or non-ECG-gated cardiac CT between May 2018 and June 2024. We excluded patients with transient ischemic attack or stroke mimics. The primary outcome was the proportion of patients with a thrombus on cardiac CT. Secondary outcomes were additional scan time, radiation dose, comparison with echocardiography, and 90-day outcomes. We performed logistic regression analyses to compare 90-day outcomes between patients with and without thrombus, adjusting for age, sex, history of atrial fibrillation, ischemic heart disease, chronic heart failure, stroke or transient ischemic attack, anticoagulant use, prestroke modified Rankin Scale score, National Institutes of Health Stroke Scale score, large vessel occlusions, and intravenous thrombolysis, as appropriate for each outcome. RESULTS: We included 3919 patients (median age, 74 [interquartile range (IQR), 63-82], 58% male, median National Institutes of Health Stroke Scale score 6 [IQR, 3-12]). Cardiac CT detected a thrombus in 243 (6.2%) patients. Among 1323 patients that underwent both cardiac CT and transthoracic echocardiography, cardiac CT had a higher yield than transthoracic echocardiography (odds ratio, 7.4 [95% CI, 4.0-15.1]; CONCLUSIONS: Implementing cardiac CT into the acute stroke imaging protocol is feasible, detects thrombi in ≈6% of patients, and has a higher yield than transthoracic echocardiography. Cardiac thrombi were associated with higher mortality, but not higher stroke recurrence. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT07165093.