Daily Cardiology Research Analysis
Analyzed 143 papers and selected 3 impactful papers.
Summary
Three impactful cardiology studies span mechanisms, risk stratification, and intervention outcomes. A Nature Communications study identifies Dlat-driven mitochondrial protein hyperacetylation that suppresses fatty acid oxidation as a mechanistic driver of HFpEF. Large clinical cohorts show that integrating LVEF with GLS and cardiac index improves prognosis in cardiac amyloidosis, and that left-sided heart failure phenotype strongly influences outcomes after transcatheter tricuspid repair.
Research Themes
- Mitochondrial acetylation and metabolic remodeling in HFpEF
- Multimodal prognostic stratification in cardiac amyloidosis
- Heart failure phenotype and outcomes after transcatheter tricuspid repair
Selected Articles
1. Pyruvate metabolism enzyme Dlat induces mitochondria protein hyperacetylation to limit fatty acid oxidation in the HFpEF heart.
This mechanistic study shows that Dlat acts as a mitochondrial transacetylase driving protein hyperacetylation in HFpEF, especially in the fatty acid oxidation pathway. Dlat acetylates HADHA at K728 to inhibit activity; genetic modulation of Dlat bidirectionally alters FAO and HFpEF phenotypes, nominating mitochondrial acetylation/Dlat as therapeutic targets.
Impact: It uncovers a previously unrecognized, targetable mitochondrial acetylation mechanism linking Dlat to FAO inhibition and HFpEF pathogenesis, providing a concrete molecular entry point in a syndrome lacking disease-modifying therapies.
Clinical Implications: Targeting mitochondrial protein acetylation or Dlat (e.g., small-molecule inhibitors or acetylation modulators) could restore FAO and ameliorate HFpEF; human tissue validation and translational studies are needed.
Key Findings
- HFpEF hearts exhibit marked mitochondrial protein hyperacetylation enriched in the fatty acid oxidation pathway.
- Dlat is identified as a key mitochondrial transacetylase driving hyperacetylation.
- Dlat overexpression increases FAO protein acetylation and worsens cardiac lipid metabolic disturbances; Dlat knockdown rescues FAO and HFpEF phenotypes.
- Dlat directly acetylates HADHA at K728, inactivating HADHA enzymatic activity.
Methodological Strengths
- Mechanistic causality established via gain- and loss-of-function of Dlat in vivo/in vitro.
- Site-specific post-translational modification mapping linking Dlat to HADHA K728 acetylation and functional readouts.
Limitations
- Preclinical models; human validation across diverse HFpEF endotypes is pending.
- Potential off-target or systemic effects of manipulating acetylation require safety evaluation.
Future Directions: Validate Dlat-HADHA acetylation axis in human HFpEF tissue; develop selective Dlat inhibitors; test pharmacologic modulation of mitochondrial acetylation in large-animal HFpEF models and early-phase trials.
Increased protein acetylation is frequently observed in the failing heart, including in hearts with heart failure with preserved ejection fraction (HFpEF). However, its role in the pathogenesis of HFpEF remains insufficiently investigated. Here, we found that HFpEF hearts displayed significantly protein hyperacetylation, which were predominantly localized to mitochondria and particularly enriched in fatty acid oxidation (FAO) pathway. Notably, Dlat, a pyruvate metabolism enzyme, was identified as the key transacetylase for mitochondrial protein hyperacetylation. Dlat overexpression enhanced FAO-related protein acetylation and exacerbated cardiac lipid metabolism disturbances, whereas Dlat knockdown effectively mitigated FAO inhibition and HFpEF phenotypes.
2. Cardiac amyloidosis across the spectrum of left ventricular function: multimodal functional and prognostic insights.
In 2,244 patients with cardiac amyloidosis, 39% presented with HFmrEF/HFrEF. A decision tree integrating LVEF, GLS, and cardiac index identified four prognostic groups with distinct 4-year mortality risks and was externally validated, supporting multimodal stratification beyond LVEF alone.
Impact: Defines a practical, validated multimodal framework that refines prognosis across EF phenotypes, a key gap in managing amyloidosis with heterogeneous ventricular function.
Clinical Implications: Incorporate GLS and cardiac index with LVEF to improve risk stratification, guide surveillance intensity, and inform timing of disease-modifying therapies (e.g., TTR silencers/stabilizers or AL-directed therapy).
Key Findings
- Among 2,244 CA patients, 39% had HFmrEF or HFrEF at presentation.
- LVEF correlated moderately with GLS and weakly with cardiac index, indicating complementary prognostic information.
- A decision tree combining LVEF, GLS, and CIx defined four prognostic groups with HRs for 4-year mortality ranging from 1.6 to 3.7.
- Findings were externally validated in an independent French cohort.
Methodological Strengths
- Large, phenotypically diverse national cohort with external validation.
- Integration of imaging (LVEF, GLS) and hemodynamics (CIx) with decision-tree modeling.
Limitations
- Observational design with potential referral/selection bias.
- Lack of interventional testing of risk-guided strategies; generalizability beyond reference centers uncertain.
Future Directions: Prospective studies to test risk-guided treatment pathways; calibration in broader health systems; incorporation of biomarkers and amyloid burden imaging into multimodal models.
BACKGROUND: Although cardiac amyloidosis (CA) is often considered to be a cause of heart failure with preserved ejection fraction (HFpEF), many patients present with mildly reduced (HFmrEF) or reduced ejection fraction (HFrEF). Recognising CA across this spectrum is essential for diagnosis and risk stratification. METHODS: We studied 2244 patients with CA (557 light chain amyloidosis, 392 hereditary transthyretin amyloidosis, 1137 wild-type transthyretin amyloidosis) at the French national reference centre. Left ventricular ejection fraction (LVEF) was classified according to European Society of Cardiology guidelines. We evaluated the prognostic relevance of LVEF and its interaction with global longitudinal strain (GLS) and cardiac index (CIx). Survival was assessed with a Kaplan-Meier analysis, and a decision tree combined LVEF, GLS and CIx. Our findings were confirmed externally in an independent, French validation cohort.
3. Left-sided heart failure determines outcomes in patients with severe tricuspid regurgitation undergoing percutaneous repair.
In 1,773 patients undergoing T-TEER, left-sided HF phenotypes had distinct procedural success rates, mortality, and predictors of survival. Procedural success (TR ≤ moderate) improved outcomes across all phenotypes, with the prognostic benefit unfolding over time particularly in HFpEF.
Impact: Provides phenotype-specific prognostic insights for T-TEER and emphasizes the central role of left-sided pathophysiology, informing patient selection, counseling, and follow-up strategies.
Clinical Implications: Assess and incorporate left-sided HF phenotype (LVEF and PCWP) when selecting candidates for T-TEER and defining goals (procedural success). Tailor surveillance to phenotype-specific predictors (e.g., RV function vs right-sided pressures).
Key Findings
- Among 1,773 T-TEER patients, distribution was 30% HFmrEF/HFrEF, 44% HFpEF, 26% non-overt left-sided HF.
- Procedural success (TR ≤ moderate) was highest in non-overt left-sided HF (87%) and lowest in HFmrEF/HFrEF (78%).
- Estimated 2-year mortality was 25.0% (HFmrEF/HFrEF), 20.3% (HFpEF), and 13.1% (non-overt left-sided HF).
- Procedural success improved outcomes in all groups; phenotype-specific predictors of survival differed (e.g., RV function vs right-sided pressures).
Methodological Strengths
- Large multicenter registry with phenotype stratification using LVEF and PCWP.
- Clinically meaningful outcomes (2-year all-cause mortality) and consistent benefit of procedural success.
Limitations
- Observational design with potential confounding and selection bias.
- Hemodynamic assessment methods (PCWP) and procedural nuances may vary across centers.
Future Directions: Prospective, phenotype-guided trials to optimize selection and timing of T-TEER; standardized hemodynamic criteria and imaging endpoints to refine procedural targets.
AIMS: Tricuspid regurgitation (TR) frequently coexists with left-sided heart failure (HF). Tricuspid valve transcatheter edge-to-edge repair (T-TEER) has emerged as a treatment for severe TR, yet the prognostic role of coexisting HF phenotypes remains unclear. METHODS AND RESULTS: In the EuroTR registry, we assessed the impact of HF subtypes on 2-year all-cause mortality after T-TEER. Patients were stratified by left ventricular ejection fraction (LVEF) into reduced/mildly reduced (HFmrEF/HFrEF <50%) and preserved (≥50%). Those with preserved LVEF were further divided by pulmonary capillary wedge pressure (PCWP) into HFpEF (>15 mmHg) and non-overt left-sided HF (≤15 mmHg). Among 1,773 patients, 30% had HFmrEF/HFrEF, 44% HFpEF, and 26% non-overt left-sided HF. Procedural success (TR ≤moderate) was highest in non-overt left-sided HF (87%) and lowest in HFmrEF/HFrEF (78%). Symptom burden improved across all groups (p<0.001). Estimated 2-year mortality was 25.0% in HFmrEF/HFrEF, 20.3% in HFpEF, and 13.1% in non-overt left-sided HF. Procedural success was associated with improved outcomes in all groups (p<0.01). Among successfully treated patients, survival was comparable between HFmrEF/HFrEF and HFpEF at 1-year but better in HFpEF at 2-years (p=0.027). Predictors of survival differed by phenotype: right ventricular function for HFmrEF/HFrEF, right-sided pressures for HFpEF, and baseline TR severity for non-overt left-sided HF. CONCLUSION: Consideration of left-sided pathologies in patients with significant TR is important as outcomes and predictors for survival differ. Across HF phenotypes, procedural success is associated with survival but the prognostic impact of TR reduction may unfold over time especially in HFpEF.