RESUMEN
BACKGROUND: Electronic health records contain vast amounts of cardiovascular data, including potential clues suggesting unrecognized conditions. One important example is the identification of left ventricular hypertrophy (LVH) on echocardiography. If the underlying causes are untreated, individuals are at increased risk of developing clinically significant pathology. As the most common cause of LVH, hypertension accounts for more cardiovascular deaths than any other modifiable risk factor. Contemporary healthcare systems have suboptimal mechanisms for detecting and effectively implementing hypertension treatment before downstream consequences develop. Thus, there is an urgent need to validate alternative intervention strategies for individuals with preexisting-but potentially unrecognized-LVH. METHODS: Through a randomized pragmatic trial within a large integrated healthcare system, we will study the impact of a centralized clinical support pathway on the diagnosis and treatment of hypertension and other LVH-associated diseases in individuals with echocardiographic evidence of concentric LVH. Approximately 600 individuals who are not treated for hypertension and who do not have a known cardiomyopathy will be randomized. The intervention will be directed by population health coordinators who will notify longitudinal clinicians and offer to assist with the diagnostic evaluation of LVH. Our hypothesis is that an intervention that alerts clinicians to the presence of LVH will increase the detection and treatment of hypertension and the diagnosis of alternative causes of thickened myocardium. The primary outcome is the initiation of an antihypertensive medication. Secondary outcomes include new hypertension diagnoses and new cardiomyopathy diagnoses. The trial began in March 2023 and outcomes will be assessed 12 months from the start of follow-up. CONCLUSION: The NOTIFY-LVH trial will assess the efficacy of a centralized intervention to improve the detection and treatment of hypertension and LVH-associated diseases. Additionally, it will serve as a proof-of-concept for how to effectively utilize previously collected electronic health data to improve the recognition and management of a broad range of chronic cardiovascular conditions. TRIAL REGISTRATION: NCT05713916.
RESUMEN
The embryotoxicity of co-planar PCBs is regulated by the aryl hydrocarbon receptor (Ahr), and has been reported to involve oxidative stress. Ahr participates in crosstalk with another transcription factor, Nfe2l2, or Nrf2. Nrf2 binds to antioxidant response elements to regulate the adaptive response to oxidative stress. To explore aspects of the crosstalk between Nrf2 and Ahr and its impact on development, we used zebrafish (Danio rerio) with a mutated DNA binding domain in Nrf2a (nrf2a(fh318/fh318)), rendering these embryos more sensitive to oxidative stress. Embryos were exposed to 2 nM or 5 nM PCB126 at 24 h post fertilization (prim-5 stage of pharyngula) and examined for gene expression and morphology at 4 days post fertilization (dpf; protruding - mouth stage). Nrf2a mutant eleutheroembryos were more sensitive to PCB126 toxicity at 4 dpf, and in the absence of treatment also displayed some subtle developmental differences from wildtype embryos, including delayed inflation of the swim bladder and smaller yolk sacs. We used qPCR to measure changes in expression of the nrf gene family, keap1a, keap1b, the ahr gene family, and known target genes. cyp1a induction by PCB126 was enhanced in the Nrf2a mutants (156-fold in wildtypes vs. 228-fold in mutants exposed to 5 nM). Decreased expression of heme oxygenase (decycling) 1 (hmox1) in the Nrf2a mutants was accompanied by increased nrf2b expression. Target genes of Nrf2a and AhR2, NAD(P)H:quinone oxidoreductase 1 (nqo1) and glutathione S-transferase, alpha-like (gsta1), showed a 2-5-fold increase in expression in the Nrf2a mutants as compared to wildtype. This study elucidates the interaction between two important transcription factor pathways in the developmental toxicity of co-planar PCBs.
