Daily Cardiology Research Analysis
Analyzed 221 papers and selected 3 impactful papers.
Summary
Analyzed 221 papers and selected 3 impactful articles.
Selected Articles
1. Direct Oral Anticoagulants Versus Dual Antiplatelet Therapy Following Left Atrial Appendage Closure in Atrial Fibrillation.
Across three randomized trials totaling 704 patients undergoing LAAC, DOAC-based regimens reduced device-related thrombosis and bleeding compared with DAPT, with no differences in stroke or all-cause mortality in the early post-implant period. These data favor DOACs as a short-term post-LAAC antithrombotic option in appropriately selected AF patients.
Impact: Clarifies a core management uncertainty with randomized evidence synthesis, supporting a shift from DAPT to DOACs after LAAC to improve safety while maintaining effectiveness.
Clinical Implications: For AF patients post-LAAC, short-term DOAC therapy can be considered instead of DAPT to lower device-related thrombosis and bleeding, pending individual bleeding/thrombotic risk assessment and device-specific protocols.
Key Findings
- Meta-analysis of three RCTs (ADRIFT, ADALA, ANDES; n=704) comparing DOAC vs DAPT after LAAC
- DOAC regimens reduced device-related thrombosis compared with DAPT
- DOAC regimens reduced bleeding events versus DAPT
- No significant differences in stroke or all-cause mortality in the early post-implant period
Methodological Strengths
- Randomized controlled trials synthesized with predefined efficacy and safety endpoints
- Comparative evaluation of clinically actionable outcomes (device-related thrombosis, bleeding)
Limitations
- Total sample size remains modest across three trials, limiting power for rare outcomes
- Short early post-implant follow-up; longer-term regimen implications remain uncertain
Future Directions: Head-to-head RCTs powered for clinical events across devices and patient subgroups, evaluation of regimen duration and de-escalation strategies, and integration with imaging/CFD-derived thrombosis risk.
BACKGROUND: Percutaneous left atrial appendage closure (LAAC) is an established alternative to oral anticoagulants for preventing thromboembolic events for selected atrial fibrillation (AF) patients. However, optimal post-procedural antithrombotic therapy remains uncertain, particularly regarding the use of direct oral anticoagulants (DOACs) versus dual antiplatelet therapy (DAPT). OBJECTIVE: This meta-analysis aimed to compare the efficacy and safety outcomes of DOACs versus DAPT in the early post-implant period following LAAC in AF patients. METHODS: We systematically searched PubMed and Embase until November 2025 to identify randomized controlled trials (RCTs) that compared DOACs with DAPT after LAAC. Efficacy outcomes included device-related thrombosis, stroke, and all-cause mortality, whereas safety outcomes encompassed major and minor bleeding. Pooled effect estimates were calculated as odds ratios (ORs) with 95% confidence intervals (CIs). Where appropriate, fixed- or random-effects models were applied according to between-study heterogeneity. RESULTS: Three RCTs (ADRIFT, ADALA, ANDES) involving 704 patients (mean age 75.8-78.4 years; 65% males) were included, with 368 assigned to DOAC and 336 to DAPT. Baseline thromboembolic and bleeding risk were high (mean CHA
2. Impact of device implantation depth on blood flow dynamics after left atrial appendage closure.
In a 10-centre cohort of 285 LAAC patients, deeper device implantation produced adverse flow features on patient-specific CFD (lower surface velocities, higher ECAP, more recirculation) and higher DRT incidence. A composite CFD-derived DRT risk score (AUC 0.81) outperformed anatomical depth alone, suggesting flow-based metrics can refine risk stratification.
Impact: Provides mechanistic, patient-specific evidence linking implantation depth to thrombogenic flow and DRT, and introduces a validated CFD risk tool that outperforms anatomy-only assessment.
Clinical Implications: Aim for proximal, flush implantation when anatomically feasible and consider CFD-informed risk assessment to individualize surveillance and antithrombotic strategies after LAAC.
Key Findings
- Proximal implants had higher device surface velocity (0.11 vs 0.09 m/s; p=0.002) and lower ECAP (0.75 vs 0.90; p=0.003)
- Recirculation zones were markedly fewer with proximal implantation (40.5% vs 74.6%; p<0.001)
- DRT incidence rose with increasing implantation depth in parallel with adverse CFD indices
- A CFD-based composite DRT risk score achieved AUC 0.81, outperforming anatomical depth alone (AUC 0.71)
Methodological Strengths
- Multicentre cohort with patient-specific CFD using CT and echo-derived boundary conditions
- Objective, quantitative flow indices and externally derived composite risk score with AUC comparison
Limitations
- Observational design; residual confounding cannot be excluded
- CFD assumptions and boundary conditions may vary across centres; limited integration of clinical variables
Future Directions: Prospective studies integrating CFD metrics with clinical risk factors to guide implantation strategy and antithrombotic therapy; testing CFD-informed interventions to reduce DRT.
BACKGROUND: Device-related thrombus (DRT) remains a concern after left atrial appendage closure (LAAC), particularly when the device is deeply implanted. However, the mechanistic links between implantation depth, flow dynamics, and DRT risk are not well understood. AIMS: We therefore aimed to evaluate the impact of LAAC device implantation depth on local flow characteristics and its association with DRT using patient-specific computational fluid dynamics (CFD). METHODS: The study included 285 patients undergoing LAAC with either Amplatzer Amulet or WATCHMAN devices at 10 centres. Patient-specific CFD simulations were performed using postprocedural computed tomography and echocardiography-derived boundary conditions to assess blood flow dynamics. The primary endpoint was the comparison of CFD-derived flow indices - device surface velocity index (DSVI), endothelial cell activation potential (ECAP), and the presence of eddies/stagnated flow - between proximal and distal device implantation groups. Secondary analyses explored the relationship between these flow features and DRT. RESULTS: Proximal implants (57.2%) showed more favourable flow patterns: higher DSVI (0.11 m/s vs 0.09 m/s; p=0.002), lower ECAP (0.75 vs 0.90; p=0.003), and fewer recirculating zones (40.5% vs 74.6%; p<0.001). DRT incidence increased with greater implantation depth, paralleled by worsening flow indices. A composite CFD-based DRT risk score, incorporating ECAP, implantation depth, and flow complexity, demonstrated good discrimination (area under the receiver operating characteristic curve [AUC] 0.81), outperforming anatomical depth alone (AUC 0.71). CONCLUSIONS: Deeper LAAC device implantation is associated with adverse flow profiles and a higher risk of DRT. CFD-based flow characterisation may enhance risk stratification beyond anatomical criteria alone. Further studies incorporating clinical variables are warranted to validate these methods.
3. Spatial and single-cell RNA sequencing reveals the immune microenvironment of human ascending thoracic aortic aneurysms.
High-throughput scRNA-seq integrated with Visium HD spatial profiling mapped 187,163 immune cells across ATAA and controls, identifying eight major immune types enriched in ATAA and strong intercellular signaling. Analyses highlighted interferon, AP-1, and NF-κB pathways and synergistic immune crosstalk as potential drivers of aneurysm remodeling.
Impact: This is the first high-resolution immune atlas of human ATAA integrating spatial context, revealing actionable inflammatory pathways. It reframes aneurysm biology around immune cell orchestration beyond structural cells.
Clinical Implications: While not immediately practice-changing, the data nominate interferon/AP-1/NF-κB signaling and immune cell interactions as targets, supporting development of anti-inflammatory strategies and biomarker-guided trials in ATAA.
Key Findings
- Profiled 187,163 immune cells across ATAA and control aortas, defining eight major immune cell types enriched in ATAA.
- CellChat analyses showed strong immune–immune signaling networks in ATAA, suggesting synergistic remodeling effects.
- Interferon, AP-1, and NF-κB pathways were highlighted as potential therapeutic targets.
Methodological Strengths
- Integration of single-cell RNA-seq with high-definition spatial transcriptomics for spatially resolved immune mapping
- Comparative design including ATAA patients and external control datasets with computational interaction analyses (CellChat)
Limitations
- Modest number of donors (8 ATAA, 9 controls) and cross-sectional design limit causal inference
- Lack of in vivo functional validation or direct linkage to clinical outcomes
Future Directions: Prospective studies correlating immune signatures with progression and outcomes; functional perturbation of interferon/AP-1/NF-κB pathways; testing targeted anti-inflammatory strategies in ATAA.
BACKGROUND: Ascending thoracic aortic aneurysm (ATAA) is a fatal vascular disease characterized by immune dysregulation. However, the cellular composition, spatial localization, and functional diversity of immune cells in the ATAA microenvironment remain poorly understood. OBJECTIVE: To construct a high-resolution immune cell atlas of human ATAA and explore the immune-mediated vascular remodelling mechanisms associated with its progression. METHOD: We conduct high-throughput single-cell RNA sequencing (scRNA-seq) of aortic tissues from eight ATAA patients and nine controls, including six from the GEO database. In the ATAA group, CD45 RESULTS: A total of 187 163 high-quality immune cells are identified, encompassing eight major immune cell types. Immune cells are significantly enriched in ATAA tissues compared with the controls. CellChat analysis reveals strong immune cell interactions in ATAA, which may contribute to its occurrence and progression. CONCLUSION: This study presents the first high-resolution immune cell atlas of human ATAA, offering novel insights into its immune-mediated vascular remodelling mechanism. KEY POINTS: What is currently known about this topic? ATAA is a vascular disease characterized by medial degeneration and chronic inflammation. Previous single-cell transcriptomic studies have revealed the cellular heterogeneity of the aortic wall and identified alterations in the populations of smooth muscle, fibroblasts and endothelial cells. However, the immune landscape of ATAA remains unclear. Recent single-cell and spatial analyses of aortic dissections and abdominal aortic aneurysms have revealed dynamic immune remodelling involving macrophage polarization, T-cell activation and cytokine-driven matrix degradation. Nevertheless, the spatial resolution of immune heterogeneity and cross-lineage signalling in human ATAA is poorly understood.