Blood Levels of Angiotensinogen and Hypertension in the Multi-Ethnic Study of Atherosclerosis (MESA).

BACKGROUND: Angiotensinogen is the proximal precursor of the angiotensin peptide hormones of the renin-angiotensin-aldosterone system (RAAS). Clinical trials are ongoing targeting angiotensinogen for the treatment of hypertension and heart failure. The epidemiology of angiotensinogen is not well defined, particularly its relationship to ethnicity, sex, and blood pressure (BP)/hypertension. OBJECTIVES: The authors sought to determine the relationship of circulating angiotensinogen levels to ethnicity, sex, BP, incident hypertension, and prevalent hypertension in a modern sex-balanced ethnically diverse cohort. METHODS: Plasma angiotensinogen levels were measured in 5,786 participants from the MESA (Multi-Ethnic Study of Atherosclerosis). Linear, logistic, and Cox proportional hazards models were utilized to examine the associations of angiotensinogen with BP, prevalent hypertension, and incident hypertension, respectively. RESULTS: Angiotensinogen levels were significantly higher in females than males and differed across self-reported ethnicities with the ordering (from highest to lowest): White, Black, Hispanic, and Chinese adults. Higher levels were associated with higher BP and odds of prevalent hypertension, after adjusting for other risk factors. Equivalent relative differences in angiotensinogen were associated with greater differences in BP in males vs females. In males not taking RAAS-blocking medications, a standard deviation increment in log-angiotensinogen was associated with 2.61 mm Hg higher systolic BP (95% CI: 1.49-3.80), while in females the same increment in angiotensinogen was associated with 0.97 mm Hg higher systolic BP (95% CI: 0.30-1.65). CONCLUSIONS: Significant differences in angiotensinogen levels are present between sexes and ethnicities. A positive association is present between levels and prevalent hypertension and BP, which differs between sexes.

Angiotensinogen: More Than its Downstream Products: Evidence From Population Studies and Novel Therapeutics.

The renin-angiotensin-aldosterone system (RAAS) is a well-defined pathway playing a key role in maintaining circulatory homeostasis. Abnormal activation of RAAS contributes to development of cardiovascular disease, including heart failure, cardiac hypertrophy, hypertension, and atherosclerosis. Although several key RAAS enzymes and peptide hormones have been thoroughly investigated, the role of angiotensinogen-the precursor substrate of the RAAS pathway-remains less understood. The study of angiotensinogen single-nucleotide polymorphisms (SNPs) has provided insight into associations between angiotensinogen and hypertension, congestive heart failure, and atherosclerotic cardiovascular disease. Targeted drug therapy of RAAS has dramatically improved clinical outcomes for patients with heart failure, myocardial infarction, and hypertension. However, all such therapeutics block RAAS components downstream of angiotensinogen and elicit compensatory pathways that limit their therapeutic efficacy as monotherapy. Upstream RAAS targeting by an angiotensinogen inhibitor has the potential to be more efficacious in patients with suboptimal RAAS inhibition and has a better safety profile than multiagent RAAS blockade. Newly developed therapeutics that target angiotensinogen through antisense oligonucleotides or silencer RNA technologies are providing a novel perspective into the pathobiology of angiotensinogen and show promise as the next frontier in the treatment of cardiovascular disease.

Apixaban: Alternative Anticoagulation for HeartMate 3 Ventricular Assist Device.

Patients with left ventricular assist devices currently require long-term anticoagulation with warfarin. Warfarin requires frequent blood tests and is associated with adverse events when not in the therapeutic range. Apixaban is a possible alternative that is potentially better for compliance and requires no additional testing. The purpose of this study was to compare adverse events in patients with a HeartMate 3 LVAD receiving apixaban versus warfarin. Thirty-five patients underwent HM3 implantation between January 01, 2016 to January 31, 2021. The groups compared were apixaban (n = 15, 43%) and warfarin (n = 20, 57%). All patients received 325 mg aspirin daily. Stroke, bleeding, and death were identified as primary outcomes after LVAD implant. Univariate nonparametric statistical analysis was performed. The median duration of treatment with apixaban was 148 days (37-606 days). The groups were comparable in terms of age (56 vs. 54 years), gender (male, 85% vs. 75%), and renal function (Cr 1.5 vs. 1.4). The apixaban group had significantly higher mean pulmonary artery pressure (41 vs. 34, p = 0.03) and there were more (p < 0.05) ischemic cardiomyopathy and INTERMACS profile >3 in the warfarin group. At 6 months, thrombotic complications and death were not different between the groups. The two deaths in the apixaban group were from right heart failure. The apixaban group had clinically lower rates of bleeding complications (5% vs. 30%). The adverse events of bleeding, stroke, and death were similar in HM3 patients receiving warfarin or apixaban. Apixaban may be a safe alternative anticoagulant therapy in HM 3 LVAD patients.

Transcatheter edge-to-edge mitral valve repair for annuloplasty ring dehiscence: The peri-ring approach.

Recurrent severe primary mitral regurgitation from annuloplasty ring dehiscence is very rare and is associated with adverse outcomes. We present a case where transcatheter edge-to-edge mitral repair with MitraClip was used in high surgical risk patient using a peri-ring approach due to unfavorable anatomy for a conventional intra-ring approach.

Cardiac Lymphoma Presenting with Recurrent STEMI.

The incidence of primary cardiac tumors is exceedingly rare, whereas secondary cardiac tumors are more common in the global population. Cardiac involvement is seen in approximately 18% of patients with non-Hodgkin's lymphoma at the time of autopsy. Clinical manifestations of cardiac involvement are subtle and often go unrecognized until advanced stages of the disease. We present a rare case of metastatic cardiac lymphoma that presented as an ST-segment elevation myocardial infarction complicated by left ventricular free wall rupture and cardiogenic shock due to transmural myocardial necrosis from malignant cell infiltration.

Mesenchymal Niche-Derived Neuregulin-1 Drives Intestinal Stem Cell Proliferation and Regeneration of Damaged Epithelium.

Epidermal growth factor (EGF) maintains intestinal stem cell (ISC) proliferation and is a key component of organoid growth media yet is dispensable for intestinal homeostasis, suggesting roles for multiple EGF family ligands in ISC function. Here, we identified neuregulin 1 (NRG1) as a key EGF family ligand that drives tissue repair following injury. NRG1, but not EGF, is upregulated upon damage and is expressed in mesenchymal stromal cells, macrophages, and Paneth cells. NRG1 deletion reduces proliferation in intestinal crypts and compromises regeneration capacity. NRG1 robustly stimulates proliferation in crypts and induces budding in organoids, in part through elevated and sustained activation of mitogen-activated protein kinase (MAPK) and AKT. Consistently, NRG1 treatment induces a proliferative gene signature and promotes organoid formation from progenitor cells and enhances regeneration following injury. These data suggest mesenchymal-derived NRG1 is a potent mediator of tissue regeneration and may inform the development of therapies for enhancing intestinal repair after injury.