Daily Cardiology Research Analysis
Analyzed 184 papers and selected 3 impactful papers.
Summary
Three impactful cardiology studies span translational, methodological, and imaging sciences. A Circulation mechanistic study identifies endothelial Hrd1 as a ubiquitin ligase that exacerbates myocardial ischemia-reperfusion injury by suppressing ALDH2 activity, nominating Hrd1 as a therapeutic target. In parallel, a JACC pooled analysis validates the KCCQ-12 as interchangeable with KCCQ-23 in >18,000 HFmrEF/HFpEF trial participants, and a JACC Cardiovascular Imaging study shows that effective RVEF on CMR outperforms conventional RVEF for mortality risk in functional tricuspid regurgitation.
Research Themes
- Ubiquitin-proteasome signaling in myocardial ischemia-reperfusion injury
- Patient-reported outcomes optimization in heart failure trials
- Imaging-derived physiologic metrics for right ventricular function in tricuspid regurgitation
Selected Articles
1. Targeting E3 Ubiquitin Ligase Hrd1 Prevents Myocardial Ischemia-Reperfusion Injury Through Enhancing ALDH2 Enzymatic Activity.
Integrative ubiquitinome, proteomic, and single-cell analyses identified endothelial Hrd1 upregulation after myocardial I/R. Genetic Hrd1 loss-of-function in mice (global heterozygous and EC-specific) mitigated endothelial dysfunction and injury, mechanistically linked to preservation of ALDH2 enzymatic activity. The study nominates endothelial Hrd1 as a druggable node to limit reperfusion injury by sustaining ALDH2 function.
Impact: This study uncovers a previously unrecognized endothelial ubiquitin ligase (Hrd1) that drives I/R injury via ALDH2 suppression, offering a mechanistically grounded cardioprotective target.
Clinical Implications: Although preclinical, targeting endothelial Hrd1 or boosting ALDH2 activity could inform next-generation cardioprotective strategies in myocardial infarction reperfusion and cardiac surgery.
Key Findings
- Endothelial protein ubiquitination is heightened after myocardial I/R and associates with endothelial dysfunction.
- Hrd1, an E3 ligase, is significantly upregulated in cardiac endothelial cells post-I/R based on integrated ubiquitinome/proteomic/single-cell analyses.
- Genetic reduction of Hrd1 (global heterozygous and endothelial cell–specific) ameliorates I/R injury, mechanistically linked to preservation/enhancement of ALDH2 enzymatic activity.
Methodological Strengths
- Unbiased global ubiquitinome profiling integrated with proteomics and single-cell RNA-seq
- Use of both global heterozygous and endothelial cell–specific Hrd1 loss-of-function mouse models
Limitations
- Preclinical animal models without human interventional validation
- Sample sizes and dosing/therapeutic windows for clinical translation are not detailed
Future Directions: Validate Hrd1–ALDH2 axis in human myocardial tissue, test pharmacologic Hrd1 inhibitors or ALDH2 activators in large-animal I/R models, and design early-phase cardioprotection trials.
BACKGROUND: Myocardial ischemia-reperfusion (I/R) injury presents a significant clinical challenge characterized by a complex pathological mechanism. The role of protein ubiquitination in I/R injury has not been systematically investigated. Global ubiquitinome profiling was conducted to identify the potential key players in myocardial I/R injury. METHODS: The ubiquitination levels of proteins in mouse hearts subjected to either sham surgery or I/R injury were analyzed using ubiquitinome. A combined analysis of ubiquitinome, single-cell RNA sequencing (RNA-seq), and proteomics data was employed to predict potential E3 ubiquitin ligases associated with myocardial I/R injury. Global heterozygous 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase degradation 1 (Hrd1) knockout, endothelial cell (EC)-specific Hrd1 deficiency (Hrd1 RESULTS: Ubiquitinome analysis revealed that protein ubiquitination exacerbates endothelial dysfunction after myocardial I/R injury. Integrative analysis of the ubiquitinome, proteomics, and single-cell RNA-seq revealed a significant upregulation of the E3 ubiquitin-protein ligase Hrd1 in CD45 CONCLUSIONS: Our findings demonstrated a previously unidentified crucial role of cardiac EC Hrd1 in myocardial I/R injury. Hrd1 may serve as a therapeutic target for preventing myocardial I/R injury.
2. Interchangeability of the KCCQ-12 and KCCQ-23 Across >18,000 Participants Enrolled in 4 Large-Scale Trials of Heart Failure.
Across 18,216 HFmrEF/HFpEF patients from four landmark RCTs, KCCQ-12 overall summary closely mirrored KCCQ-23 (ρ=0.987), with comparable discrimination for CV death/HF hospitalization and near-identical treatment responsiveness (<1-point differences). Findings support KCCQ-12 as a lower-burden alternative endpoint for HF trials.
Impact: Reduces patient and site burden in large HF trials without compromising prognostic or treatment-effect information, enabling broader adoption of PROs.
Clinical Implications: Trials and clinics can preferentially use KCCQ-12 to streamline assessments while preserving prognostic validity in HFmrEF/HFpEF populations.
Key Findings
- KCCQ-12 overall summary strongly correlated with KCCQ-23 (Spearman ρ=0.987), stable across subgroups and visits.
- Comparable prognostic discrimination for cardiovascular death and HF hospitalization (C-index 0.586 vs 0.583).
- Treatment effects on KCCQ changes were virtually identical across instruments (all differences <1 point on 0–100 scale).
Methodological Strengths
- Participant-level pooled analysis from four large randomized heart failure trials
- Consistent validation across multiple therapies, time points, and subgroups
Limitations
- KCCQ-12 scores were derived from KCCQ-23 items rather than independently administered forms
- Generalisability primarily to HFmrEF/HFpEF; external contexts (languages, settings) require confirmation
Future Directions: Prospectively administer KCCQ-12 standalone across HF phenotypes, assess measurement equivalence across languages, and integrate into digital PRO workflows.
BACKGROUND: The 23-item Kansas City Cardiomyopathy Questionnaire (KCCQ-23) is formally qualified by the Food and Drug Administration as a valid patient-reported outcome measure for use in heart failure (HF) clinical trials. However, its length may increase respondent burden. The 12-item version (KCCQ-12) provides a more efficient alternative but was originally developed and validated in HF with reduced left ventricular ejection fraction (LVEF), and its performance relative to the KCCQ-23 has not been evaluated in HF with mildly reduced or preserved LVEF (HFmrEF/HFpEF). OBJECTIVE: The purpose of this study is to examine the interchangeability of KCCQ-12 and KCCQ-23 in patients with HFmrEF/HFpEF. METHODS: We conducted a participant-level pooled analysis of 4 randomized clinical trials (TOPCAT, PARAGON-HF, DELIVER, and FINEARTS-HF), including adults with HFmrEF/HFpEF. All trials collected the KCCQ-23 at baseline and follow-up visits. In this study, the KCCQ-12 overall summary scores (OSS) were derived from individual items of the KCCQ-23 OSS. Both scores ranged from 0 (worst) to 100 (best). We assessed concordance between KCCQ-12 OSS and KCCQ-23 OSS and compared prognostic discrimination and treatment-related changes. RESULTS: Of 18,216 participants (mean age: 72 ± 9 years; female: 46%; NYHA functional class II: 72%; mean LVEF: 55 ± 8%; median N-terminal pro-B-type natriuretic peptide levels: 987 [IQR: 517-1,781] pg/mL), baseline KCCQ-23 OSS was 65.5 ± 21.4, and KCCQ-12 OSS was 64.1 ± 21.7. Baseline KCCQ-12 OSS strongly correlated with KCCQ-23 OSS (Spearman ρ = 0.987), consistent across major subgroups and follow-up visits (all Spearman ρ > 0.980). Prognostic discrimination for cardiovascular death and HF hospitalization was comparable (C index: 0.583 for KCCQ-23 vs 0.586 for KCCQ-12). Treatment effects of HF drugs on KCCQ-OSS were similar across the 2 instruments in each trial and at each time point (all the differences between KCCQ-23 and KCCQ-12 were <1 point on a 0-100 scale). CONCLUSIONS: In patients with HFmrEF/HFpEF, the KCCQ-12 closely parallels the KCCQ-23, demonstrating comparable prognostic performance and treatment responsiveness. These findings support the KCCQ-12 as a lower-burden alternative for use in HF clinical trials. (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist; NCT00094302; Prospective Comparison of Angiotensin Receptor-Neprilysin Inhibitor with Angiotensin Receptor Blocker Global Outcomes in HF with Preserved Ejection Fraction; NCT01920711; Dapagliflozin Evaluation to Improve the Lives of Patients With Preserved Ejection Fraction Heart Failure; NCT03619213; Finerenone Trial to Investigate Efficacy and Safety Superior to Placebo in Patients with Heart Failure; NCT04435626).
3. Redefining Right Ventricular Function: Incremental Prognostic Utility of Effective RVEF on CMR in Functional Tricuspid Regurgitation-A Multicenter Validation Study.
In functional TR, CMR-derived effective RVEF (forward volume/RV EDV) independently predicted all-cause mortality and improved model performance beyond conventional RVEF and clinical markers. An eRVEF ≤25% identified high-risk patients, with external validation confirming findings across two cohorts.
Impact: Provides a physiologically anchored RV performance metric that outperforms conventional RVEF for risk stratification in TR, potentially informing timing of intervention and follow-up.
Clinical Implications: Incorporating eRVEF into TR assessment may refine risk stratification and clinical decision-making, especially when conventional RVEF underestimates risk.
Key Findings
- Effective RVEF (forward volume/RV EDV) ≤25% was associated with higher mortality (derivation HR 1.72; external validation HR 2.66–2.86).
- eRVEF remained independently predictive after adjusting for age, RV size, TR severity, conventional RVEF, and right-sided congestion.
- Adding eRVEF improved mortality prediction over RVEF (chi-square 30.6→37.0; P=0.011), whereas adding RVEF to eRVEF did not.
Methodological Strengths
- Derivation and external validation across three multicenter CMR cohorts
- Rigorous adjustment for conventional RV metrics and clinical TR risk markers
Limitations
- Observational design limits causal inference
- Threshold derived on mortality may require calibration in different populations and scanners
Future Directions: Prospective studies to test eRVEF-guided management strategies and integration with intervention timing; evaluate reproducibility across vendors and imaging protocols.
BACKGROUND: Right ventricular ejection fraction (RVEF) is a known predictor of adverse outcomes; however, its prognostic value diminishes in tricuspid regurgitation (TR). OBJECTIVES: This study aims to assess whether effective right ventricular ejection fraction (eRVEF) offers a more physiologic assessment of RV function and improves risk stratification in patients with TR. METHODS: The derivation cohort comprised 453 consecutive patients with at least moderate functional TR (regurgitant fraction ≥30% or volume ≥30 mL) on cardiac magnetic resonance (CMR). eRVEF was calculated as the ratio of forward volume to RV end-diastolic volume. The eRVEF threshold (≤25%) was derived based on all-cause mortality data. Clinical data were collected from standardized questionnaires at the time of CMR and supplemented with electronic health records; the primary outcome was all-cause mortality. External validation was performed in 2 independent cohorts, totaling 316 patients using identical inclusion criteria. RESULTS: In the derivation cohort, impaired eRVEF was associated with more advanced biventricular remodeling, worse biventricular function, and greater burden of late gadolinium enhancement (P < 0.05 for all), which was paralleled by higher TR volume and fraction (both P < 0.05). Over a median follow-up period of 2.7 years (Q1-Q3: 0.6-6.6 years), 20% of the patients died; mortality was higher in patients with impaired versus preserved eRVEF (28% vs 12%; HR: 1.72 [95% CI: 1.16-2.54]; P = 0.007). After adjusting for known TR risk markers including age, RV size, TR severity, conventional RVEF, and clinical markers of right-sided congestion, eRVEF remained independently predictive of mortality (HR: 0.49 [95% CI: 0.24-0.97]; P = 0.042). Adding eRVEF to a model inclusive of RVEF improved mortality prediction (chi-square from 30.6 to 37.0; P = 0.011) whereas adding RVEF to eRVEF did not (chi-square from 35.4 to 37.0; P = 0.199). External validation confirmed the prognostic significance of eRVEF ≤25% in both cohorts (HR: 2.66-2.86; both P < 0.05). CONCLUSIONS: eRVEF independently predicts mortality in TR and provides incremental prognostic value over conventional prognostic markers.