Daily Cardiology Research Analysis
Three studies stood out today: the first randomized trial in MINOCA demonstrated that etiology-guided, stratified care significantly improves angina-related health status; a mechanistic study revealed that the ALDH2 rs671 variant amplifies platelet activation via mitochondrial complex I disruption, with NAD+ supplementation mitigating thrombosis; and a double-blind RCT in CKD showed dapagliflozin reduces left ventricular mass index, illuminating a cardiac remodeling pathway.
Summary
Three studies stood out today: the first randomized trial in MINOCA demonstrated that etiology-guided, stratified care significantly improves angina-related health status; a mechanistic study revealed that the ALDH2 rs671 variant amplifies platelet activation via mitochondrial complex I disruption, with NAD+ supplementation mitigating thrombosis; and a double-blind RCT in CKD showed dapagliflozin reduces left ventricular mass index, illuminating a cardiac remodeling pathway.
Research Themes
- Stratified, etiology-guided management in MINOCA
- Genetic-mitochondrial mechanisms of thrombosis (ALDH2 rs671) and NAD+ rescue
- SGLT2 inhibitors and cardiac remodeling in chronic kidney disease
Selected Articles
1. Stratified treatment of myocardial infarction with non-obstructive coronary arteries: the PROMISE trial.
This first multicenter RCT in MINOCA shows that an etiology-guided, stratified management strategy significantly improved Seattle Angina Questionnaire scores at 12 months versus standard care. Although MACE rates were numerically lower, the trial was underpowered for hard outcomes and was stopped early for benefit.
Impact: It establishes proof-of-concept that individualized, etiology-guided care improves patient-reported outcomes in MINOCA, a previously evidence-free zone. This can shift diagnostic and management paradigms toward routine comprehensive workups.
Clinical Implications: Clinicians should consider comprehensive diagnostic evaluation (e.g., coronary vasomotion testing, intravascular imaging, myocarditis workup) to tailor therapy after MINOCA, as this may meaningfully improve angina-related quality of life. Larger pragmatic trials are needed before guideline changes for MACE reduction.
Key Findings
- Stratified treatment improved SAQ summary score by +9.38 points at 12 months (95% CI 6.81–11.95; p<0.001).
- Numerically fewer MACE with stratified care (2.2% vs 8.5%; p=0.18), but underpowered for hard outcomes.
- Trial was stopped early due to benefit in the intervention arm and potential harm in controls.
Methodological Strengths
- Randomized, multicenter design directly comparing stratified treatment versus standard care.
- Patient-centered primary endpoint (SAQ) with clinically meaningful difference.
Limitations
- Small sample size (n=92 analyzed) and early termination limiting power for MACE.
- Open-label nature likely; potential performance and detection bias.
Future Directions: Conduct adequately powered, multicenter RCTs with longer follow-up to test MACE reduction; standardize diagnostic workup protocols and decision algorithms for MINOCA.
BACKGROUND AND AIMS: Myocardial infarction with non-obstructive coronary arteries (MINOCA) is associated with a significant risk of mortality, rehospitalisation, and angina burden. Despite its clinical impact, no randomized clinical trials have hitherto evaluated optimal management strategy for MINOCA. The PROMISE trial was designed to assess whether a stratified treatment improves clinical outcomes in patients with MINOCA as compared to standard care. METHODS: PROMISE is a multicentre randomised trial. Patients with MINOCA were randomised 1:1 to either a stratified treatment based on a comprehensive diagnostic workup aimed at identifying the underlying aetiology, or to standard care. The primary endpoint was the between-group difference in the change in angina status at 12 months, assessed by the Seattle Angina Questionnaire summary score (SAQSS). The secondary endpoint was the incidence of major adverse cardiovascular events (MACE), defined as the composite of all-cause mortality, myocardial infarction, stroke, heart failure hospitalization and repeated coronary angiography. The trial was terminated early upon recommendation by the Data and Safety Monitoring Board due to clear benefits observed in the intervention group and potential harm in the control group. RESULTS: Of 101 randomized patients, 92 were confirmed as MINOCA and included in the final analysis (mean age 62±13 years, 48% women; stratified treatment n=45; standard care n=47). At 12-month follow-up, SAQSS was significantly higher in the stratified treatment than in standard care group, with a mean between-group difference of +9.38 in favour of the stratified treatment (95% confidence interval 6.81 to 11.95; p<0.001). MACE occurred in 1 patient (2.2%) in the stratified treatment and in 4 patients (8.5%) in the standard care group, though the difference was not statistically significant (p= 0.18). CONCLUSIONS: In this first randomized trial of treatment strategies in MINOCA, a stratified treatment, based on comprehensive diagnostic assessment and aetiology-guided therapy, led to a significant improvement in angina-related health status. While the study findings provide the first evidence supporting individualized management in this heterogeneous and often under-recognized patient population, these results require confirmation in a larger prospective study with longer follow-up.
2. Cardiac Effects of Dapagliflozin in People with Chronic Kidney Disease.
In a 6‑month, randomized, double‑blind trial of 222 CKD patients, dapagliflozin significantly reduced left ventricular mass index versus placebo, suggesting early reverse remodeling as a mechanism for cardioprotection in CKD. The cohort was heterogeneous and included low diabetes prevalence.
Impact: Provides mechanistic evidence that SGLT2 inhibition reduces LV mass in CKD, aligning biological plausibility with prior clinical benefits and supporting broader use beyond diabetes.
Clinical Implications: Supports SGLT2 inhibitor initiation in CKD patients to improve cardiac structure, potentially lowering future heart failure risk; long-term outcome confirmation remains needed.
Key Findings
- Randomized, double-blind design; 222 CKD patients assigned to dapagliflozin vs placebo for 6 months.
- Dapagliflozin reduced LV mass index versus placebo (estimated mean difference approximately −8.44 g/m²).
- Benefits observed in a heterogeneous CKD population with low diabetes prevalence, suggesting kidney-centric cardioprotection.
Methodological Strengths
- Randomized, double-blind, placebo-controlled design with prespecified echocardiographic endpoints.
- Mechanistic focus complements prior outcome trials, enhancing biological plausibility.
Limitations
- Single-center design and relatively short 6-month follow-up.
- Primary endpoint is surrogate (LV mass index) rather than clinical outcomes.
Future Directions: Multicenter trials with longer follow-up to link LV mass regression to reduced HF events in CKD; explore dose-response and interaction with RAAS blockade and diuretics.
BACKGROUND: Adverse cardiac remodeling is common in people with chronic kidney disease and contributes to increased cardiovascular risk. Although sodium-glucose cotransporter 2 (SGLT2) inhibitors have shown cardioprotective effects in patients with chronic kidney disease, the underlying mechanisms are still not completely understood. This trial evaluated the impact of SGLT2 inhibitors on cardiac structure and function in patients with chronic kidney disease. METHODS: Effects of Dapagliflozin on EChOcardiographic Measures of CarDiac StructurE and Function in Patients with Chronic Kidney Disease (DECODE-CKD) was a 6-month, single-center, randomized, double-blind trial comparing dapagliflozin with placebo in patients with an estimated glomerular filtration rate of 20 to 59 or greater than or equal to 60 ml/minute/1.73 m RESULTS: Of 268 screened individuals, 222 were randomly assigned. The mean age was 67.5 years; 29.3% were women. Cardiovascular disease was present at enrollment in 34.2%, heart failure in 5.9%, hypertension in 75.7%, and diabetes in 8.6%. The most common causes of chronic kidney disease were hypertensive nephropathy (25.7%) and polycystic kidney disease (16.7%). The estimated mean difference in left ventricular mass index between the dapagliflozin group compared with placebo was -8.44 g/m CONCLUSIONS: In a heterogeneous population of patients with chronic kidney disease, dapagliflozin significantly reduced left ventricular mass index compared with placebo. These findings provide mechanistic insights into the early treatment benefits of SGLT2 inhibitors seen previously in chronic kidney disease. Further research is needed to replicate and further define these early treatment benefits. (Funded by the Danish Cardiovascular Academy and Novo Nordisk Foundation; ClinicalTrials.gov number, NCT05359263.).
3. ALDH2 rs671 variant enhances platelet activation and thrombosis by disrupting mitochondrial complex I assembly.
Across human carriers and murine Aldh2-deficient/knock-in models, ALDH2 rs671 drives collagen-triggered platelet hyperreactivity via impaired mitochondrial complex I assembly and ROS signaling. NAD+ supplementation reverses hyperreactivity and reduces thrombosis, suggesting a genotype-directed preventive strategy.
Impact: Identifies a mitochondria-centered mechanism linking a highly prevalent East Asian variant to thrombosis and provides an actionable, low-cost intervention (NAD+) with translational potential.
Clinical Implications: Genotype-informed risk assessment for ALDH2 rs671 carriers may be warranted; NAD+ supplementation emerges as a potential adjunct to mitigate platelet hyperreactivity and thrombotic risk, meriting clinical trials.
Key Findings
- ALDH2 rs671 carriers showed enhanced collagen-induced platelet reactivity versus noncarriers in CAD patients.
- Aldh2−/− and Aldh2E487K/E487K mice exhibited increased aggregation, degranulation, and αIIbβ3 activation.
- ALDH2 deficiency impaired mitochondrial complex I assembly, increasing ROS via GPVI/NOX1 signaling.
- NAD+ supplementation reversed platelet hyperreactivity and reduced thrombosis in mice and human subjects.
Methodological Strengths
- Convergent evidence across human participants and multiple murine genetic models.
- Mechanistic depth using immunoprecipitation, mass spectrometry, RNA-seq, and interventional NAD+ rescue.
Limitations
- Clinical endpoints not tested; human sample size and demographics not fully detailed in abstract.
- Long-term safety/optimal dosing of NAD+ supplementation remains to be established.
Future Directions: Prospective trials testing NAD+ supplementation in rs671 carriers with validated platelet endpoints and thrombotic outcomes; explore interactions with antiplatelet regimens.
AIMS: Aldehyde dehydrogenase 2 (ALDH2) is a critical mitochondrial enzyme responsible for aldehyde detoxification and maintenance of redox homeostasis. The rs671 variant, a prevalent loss-of-function mutation in East Asian populations (30-50% carrier frequency), diminishes ALDH2 enzymatic activity by 60-90% and is associated with elevated thrombotic risk. Although platelet activation is known to play a central role in thrombosis formation, the specific contribution of ALDH2 to this process has not been fully elucidated. This study was designed to investigate the functional role of ALDH2 in platelet activation and thrombus formation. METHODS AND RESULTS: Platelet activation and thrombus formation were assessed in wild-type (WT), systemic Aldh2-knockout (Aldh2-/-), and systemic Aldh2E487K/E487K-knockin mice, as well as patients with coronary artery disease (CAD) and healthy volunteers. Mechanistic studies were performed using immunoprecipitation, mass spectrometry, and RNA sequencing. Nicotinamide adenine dinucleotide (NAD+) supplementation was evaluated for its potential to mitigate the effects of ALDH2 variant. Patients with CAD carrying the ALDH2 rs671 variant exhibited enhanced platelet reactivity to collagen compared with those without the variant. Collagen-induced platelet aggregation, granule release, and integrin αIIbβ3 activation were significantly enhanced in Aldh2-/- mice compared with WT mice. Mechanistically, ALDH2 deficiency disrupted mitochondrial complex I assembly and function. This increased reactive oxygen species production via the collagen/glycoprotein VI (GPVI)/NAD phosphate oxidase 1 (NOX1) pathway and enhanced platelet reactivity. Similar results were observed in Aldh2E487K/E487K-knockin mice. NAD+ supplementation effectively counteracted ALDH2 variant-induced platelet hyperreactivity and thrombosis in both mice and human subjects. CONCLUSION: The ALDH2 rs671 variant enhances collagen-induced platelet activation and thrombosis by impairing mitochondrial complex I assembly and function. NAD+ supplementation offers a promising strategy to mitigate thrombotic risk in individuals carrying this variant.