A recent Cardiology digest,
as sent to subscribers

Study Type: Prospective cohort study (pooled analysis of Nurses' Health Study and Health Professionals Follow-Up Study)

Key Question: Does adherence to healthy dietary patterns after myocardial infarction (MI), and changes in adherence over time, influence long-term survival in MI survivors?

Key Findings:

• Across 8 dietary quality indices, highest vs lowest adherence quintiles were associated with 23–34% lower total mortality (HRs 0.66–0.77), with concordant reductions in cardiovascular death and recurrent nonfatal MI.
• Improving diet quality (Alternate Healthy Eating Index) from pre- to post-MI was associated with 14% lower mortality (HR 0.86, 95% CI 0.76–0.97); worsening adherence was linked to higher mortality across most patterns.
• Benefits were consistent across Mediterranean, DASH, plant-based, and anti-inflammatory/insulinaemic dietary constructs, suggesting a generalisable "diet quality" effect rather than one specific pattern.

Clinical Relevance: Supports incorporating structured dietary quality counselling (not restricted to Mediterranean or DASH diets specifically) into UK secondary prevention pathways and cardiac rehabilitation programmes for MI survivors.

Limitations: Observational design in US health professionals limits causal inference and generalisability to a more diverse UK population.

Study Type: Preclinical mechanistic study (animal models and in vitro assays, with limited human correlative data).

Key Question: Does METTL7B, a novel RNA m6A methyltransferase, regulate vascular smooth muscle cell (VSMC) function and blood pressure, and can it be therapeutically targeted?

Key Findings:

• METTL7B acts as a METTL3-independent m6A methyltransferase; VSMC-specific knockout worsened angiotensin II-induced hypertension and vascular remodeling, while overexpression was protective.
• Mechanism: METTL7B recruits HNRNPH1 to methylate FILIP1L mRNA, reducing FLNA-mediated F-actin polymerisation and VSMC contractility; FILIP1L overexpression rescued the knockout phenotype (m6A-site mutation did not).
• Stress-activated KLF4 suppresses METTL7B transcription; the repurposed drug netarsudil activated METTL7B and lowered blood pressure in vivo, with effects abolished in VSMC-specific knockouts.

Clinical Relevance: Identifies a novel epitranscriptomic pathway and a repurposable FDA-approved drug (netarsudil) with potential as a future antihypertensive strategy, relevant to NHS efforts in developing novel therapies for treatment-resistant hypertension.

Limitations: Findings are derived from murine models and in vitro systems; human translational and clinical efficacy data are lacking.

Study Type: Translational research combining human proteomic cohort analysis with mechanistic in vitro/in vivo experiments.

Key Question: Does site-specific glycation of apo AI impair HDL function and contribute to atherosclerosis in patients with type 2 diabetes?

Key Findings:

• Glycation at apo AI residues K96 and K106/107 distinguished diabetic patients with coronary atherosclerosis (n=860) from diabetic controls without CAS (n=294); a derived Apo AI Glycation Index was independently associated with CAS/CAD and inversely correlated with reverse cholesterol transport and LCAT activity.
• A glycation-resistant apo AI mutant (apo AICL) preserved structural stability, LCAT binding, and cholesterol efflux, reducing HDL dysfunction and atherosclerotic burden in diabetic mouse models.
• Mechanistically, glycated apo AI activates RAGE–ERK1/2–NF-κB signalling, upregulating NR2C2 and suppressing LXRα-driven macrophage cholesterol efflux.

Clinical Relevance: Identifies a novel, biologically plausible biomarker (Apo AI Glycation Index) and therapeutic target relevant to residual cardiovascular risk in diabetic patients, a population of major concern within NHS cardiometabolic services.

Limitations: Findings are largely mechanistic and preclinical; clinical utility of the glycation index requires prospective validation and outcome-based studies before adoption.

Study Type: Retrospective multicenter cohort study (25 centres, international)

Key Question: How effective are ICDs at preventing sudden cardiac death in patients with hypertrophic cardiomyopathy across a large, real-world global population?

Key Findings:

• 16% of 3387 patients received ≥1 appropriate ICD therapy (2.6%/year); rates were higher for secondary prevention (35%, 6.4%/year) than primary prevention (15%, 2.2%/year).
• Among primary prevention patients, median time to first appropriate therapy was 4 years, with 16% occurring ≥10 years post-implant and 47% experiencing multiple interventions.
• HCM-related mortality was low (0.3%/year); 10- and 20-year survival free from HCM-related death were 97% and 91% respectively; sudden death despite ICD occurred in only 0.4%.

Clinical Relevance: Provides the largest, most robust international evidence base supporting current primary prevention ICD strategies in HCM, reinforcing UK/NICE risk-stratification practice and long-term device follow-up planning.

Limitations: Retrospective design across heterogeneous centres/eras introduces variability in implantation criteria, device technology, and follow-up practices.

Study Type: Preclinical experimental study (transcriptomic profiling, genetically engineered mouse models, and human engineered heart tissue).

Key Question: Can combined activation of a proliferation stimulator (Nfyb) and inhibition of a cytokinesis repressor (Nr3c1) enhance cardiomyocyte regeneration after myocardial infarction?

Key Findings:

• Nfyb overexpression promoted cardiomyocyte cell-cycle gene transcription and improved post-MI repair; Nr3c1 inhibition independently increased proliferation, improved cardiac function, and reduced infarct size.
• A spatiotemporally controlled AAV9 system combining inducible Nfyb overexpression with CRISPR-mediated Nr3c1 deletion produced synergistic new cardiomyocyte formation (28% clustered, >28-fold vs control) in clonal MADM analysis.
• Benefits were replicated in post-MI mice and human engineered heart tissue, supporting translational relevance.

Clinical Relevance: This dual-gene approach offers a novel, controllable regenerative strategy that could inform future myocardial repair therapies for NHS patients with post-MI heart failure, though remains preclinical.

Limitations: Findings are based on animal models and human tissue constructs, not clinical trials, so safety, delivery, and efficacy in humans remain unproven.

Study Type: Prospective single-centre registry with propensity score-weighted comparative analysis

Key Question: Does pulsed field ablation (PFA) carry a different 30-day risk of stroke/TIA compared with radiofrequency ablation (RFA) for atrial fibrillation?

Key Findings:

• 30-day stroke/TIA rate was significantly higher with PFA (0.47%, 10/2144) than RFA (0.10%, 2/2077); weighted risk difference 0.36% (95% CI 0.03–0.70%; P=0.03).
• Events were spread evenly across the study period and operators (no operator with ≥2 events), arguing against a learning-curve or device-adoption effect.
• PFA procedures were shorter (108 vs 144 min) and more often included posterior wall isolation (57% vs 31%); mediation analysis did not identify ablation extent as an independent risk factor, though power was limited.

Clinical Relevance: As UK centres rapidly adopt PFA (Farawave, Sphere-9, Varipulse, PulseSelect) based on presumed superior safety, this signals a need for cautious interpretation and robust post-market surveillance rather than assumed neurological safety advantage over RFA.

Limitations: Single-centre, non-randomised design with low absolute event numbers limits generalisability and causal inference regarding mechanism.

Study Type: Scientific statement (expert consensus/narrative review) — not original research.

Key Question: How should clinicians distinguish and manage primary versus secondary Raynaud phenomenon (RP), including emerging diagnostic and therapeutic approaches?

Key Findings:

• PRP is typically benign, affects younger women, and rarely causes tissue damage, whereas SRP occurs later in life secondary to systemic disease (e.g., connective tissue disorders) and carries risk of digital ischaemia/ulceration.
• Evidence base for RP treatment is limited; management combines lifestyle measures with pharmacotherapy, with botulinum toxin and surgery reserved for severe/refractory SRP.
• Advanced imaging (e.g., nailfold capillaroscopy) may enable earlier identification of SRP and underlying systemic disease.

Clinical Relevance: UK cardiologists and vascular specialists should recognise SRP as a marker of systemic disease requiring prompt investigation and multidisciplinary management to prevent ischaemic complications, relevant to NHS rheumatology-cardiology referral pathways.

Limitations: As a consensus statement rather than primary research, conclusions rely on heterogeneous, often low-quality evidence with few randomised trials.

Study Type: Clinical primer/narrative review (expert guidance, not original research)

Key Question: How should clinicians select and titrate vasoactive agents in cardiogenic shock based on pharmacology, phenotype, and evolving hemodynamics?

Key Findings:

• Proposes a stepwise framework: (1) emergently protect mean arterial pressure, (2) define hemodynamic phenotype and identify/address underlying etiology in parallel, (3) set hemodynamic goals beyond MAP, (4) iteratively tailor pharmacotherapy based on perfusion reassessment.
• Emphasises matching vasoactive agent choice to the pathophysiology of specific cardiogenic shock phenotypes rather than a one-size-fits-all approach.
• Summarises pharmacologic profiles and comparative effectiveness data for currently available vasoactive agents.

Clinical Relevance: Offers UK cardiology teams (including cardiac ICU/CCU staff) a practical, phenotype-driven framework to standardise vasopressor/inotrope selection in cardiogenic shock, an area with limited high-quality comparative trial evidence.

Limitations: As a narrative primer rather than systematic review or trial, recommendations rely on expert synthesis and existing (often limited) comparative data rather than new empirical evidence.