Objective: Heart chymase rather than angiotensin converting enzyme has higher specificity for angiotensin (Ang) I conversion into Ang II in humans. A new pathway for direct cardiac Ang II generation has been revealed through the demonstration that Ang-(1-12) is cleaved by chymase to generate Ang II directly. We address here whether Ang-(1-12) and chymase gene expression and activity are detected in the atrial appendages of 44 patients (10 females) undergoing heart surgery for the correction of valvular heart disease, resistant atrial fibrillation or ischemic heart disease.
Methods And Results: Immunoreactive Ang-(1-12) expression was 54% higher in left atrial compared with right atrial appendages. This was associated with higher abundance of left atrial appendage chymase gene transcripts and chymase activity, but no differences in angiotensinogen mRNA. Atrial chymase enzymatic activity was highly correlated with left atrial but not right atrial enlargement as determined by echocardiography, while both tyrosine hydroxylase and neuropeptide Y atrial appendage mRNAs correlated with atrial angiotensinogen mRNAs.
Conclusions: Higher Ang-(1-12) expression and upregulation of chymase gene transcripts and enzymatic activity from the atrial appendages connected to the enlarged left versus right atrial chambers of subjects with left heart disease defines a role of this alternate Ang II forming pathway in the processes accompanying adverse atrial and ventricular remodeling.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5823505 | PMC |
http://dx.doi.org/10.1177/1753944715589717 | DOI Listing |
Cardiovasc Eng Technol
January 2025
Institute for Medical Engineering and Science, Massachusetts Institute of Technology, MA, Cambridge, USA.
Purpose: Atrial fibrillation (AF) is the most common chronic cardiac arrhythmia that increases the risk of stroke, primarily due to thrombus formation in the left atrial appendage (LAA). Left atrial appendage occlusion (LAAO) devices offer an alternative to oral anticoagulation for stroke prevention. However, the complex and variable anatomy of the LAA presents significant challenges to device design and deployment.
View Article and Find Full Text PDFRev Port Cardiol
January 2025
Cardiology Department, Hospital Santa Cruz, Centro Hospitalar Lisboa Ocidental, Lisbon, Portugal.
Introduction And Objectives: Pulmonary vein (PV) isolation is one of the cornerstones of rhythm-control therapy for symptomatic atrial fibrillation (AF) patients. Pulsed field ablation (PFA) is a novel ablation modality that involves the application of electrical pulses causing cellular death, and it has preferential tissue specificity. In this study, we aimed to share a one-year single center experience of AF ablation with PFA.
View Article and Find Full Text PDFAm Heart J
January 2025
Kaufman Center for Heart Failure Treatment and Recovery, Heart Vascular and Thoracic Institute, Cleveland Clinic, Cleveland, OH. Electronic address:
Background: We aim to validate NT-proBNP nonresponse score (NNRS) previously derived from the PROTECT and BATTLESCARRED studies in comparison with standard health status measures in predicting natriuretic peptide responses in patients with heart failure with reduced ejection fraction.
Methods: Data on the GUIDE-IT trial were used to derive the NNRS based on 4 predictors including baseline NT-proBNP, heart rate, NYHA functional class, and history of atrial fibrillation. The discriminative capacity of the NNRS and health status measures for having NT-proBNP >1,000 pg/mL at 12 months was assessed and compared with baseline or follow-up health status measures including Kansas City Cardiomyopathy Questionnaire Overall Summary Score (KCCQ-OSS), Duke Activity Status Index (DASI), and 6-minute walk distance.
JAMA Neurol
January 2025
Department of Neurology, UAB Heersink School of Medicine, University of Alabama at Birmingham, Birmingham.
Importance: In the Atrial Cardiopathy and Antithrombotic Drugs in Prevention After Cryptogenic Stroke (ARCADIA) randomized clinical trial, anticoagulation did not prevent recurrent stroke among patients with a recent cryptogenic stroke and atrial cardiopathy. It is unknown whether anticoagulation prevents covert infarcts in this population.
Objective: To test the use of apixaban vs aspirin for prevention of nonlacunar covert infarcts after cryptogenic stroke in patients with atrial cardiopathy.
Curr Cardiol Rep
January 2025
Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
Purpose Of Review: This review aims to explore how a diagnosis of LMNA-related cardiomyopathy (LMNA-CM) informs clinical management, focusing on the prevention and management of its complications, through practical clinical strategies.
Recent Findings: Longitudinal studies have enhanced our understanding of the natural history of LMNA-CM including its arrhythmic and non-arrhythmic complications. A LMNA specific ventricular arrhythmia risk prediction strategy has been integrated into clinical practice guidelines.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!