Objectives: Current preclinical models of pulmonary arterial hypertension do not reproduce the clinical characteristics of congenital heart anomalies. Aortocaval shunt is relevant to a variety of clinical conditions. The pathophysiology and possible determination of pulmonary hypertension in this model are still undefined.
Methods: A method to create a standardized and reproducible aortocaval shunt was developed in rats. After creation of the shunt, the animals were followed up for 20 weeks and a sham laparotomy was used as a control. The chronic effects of volume overload on the right and left ventricles and pulmonary hemodynamic modifications were evaluated by biventricular catheterization, echocardiography, and magnetic resonance. Pulmonary vascular changes were defined by histology.
Results: An increased right ventricular end-diastolic area was confirmed by echocardiography. Left ventricular overload and decreased biventricular ejection fraction were demonstrated by magnetic resonance after 20 weeks in the shunt group compared with the controls (left ventricle, 50% ± 5% vs 62% ± 3%, P = .029; right ventricle, 53% ± 2% vs 65% ± 2%, P = .036). Preload recruitable stroke work of left and right ventricles decreased after 20 weeks in shunt rats (left ventricle: 36 ± 7 vs 98 ± 5, P = .004; right ventricle: 19 ± 2 vs 32 ± 9, P = .047). At the same time point, catheterization showed that effective pulmonary arterial elastance was increased only in the shunt group (1.29 ± 0.20 vs 0.14 ± 0.06 mm Hg/μL; P = .004). Histology showed medial hypertrophy, small artery luminal narrowing, and occlusion.
Conclusions: The aortocaval shunt model reliably produces right ventricular volume overload and secondary pulmonary hypertension. Due to a combination of left ventricular dysfunction and pulmonary overflow, the pulmonary hypertension produced shows features similar to those found in patients with chronic atrial-level shunt.
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http://dx.doi.org/10.1016/j.jtcvs.2014.04.044 | DOI Listing |
Arterioscler Thromb Vasc Biol
February 2025
Department of Pediatrics (T.S., J.-R.M., Y.H.C., J.M.S., J. Kaplan, A.C., L.W., D.G., S.T., S.I., M.D., W.Y., A.L.M., M.R.).
Background: Computational modeling indicated that pathological high shear stress (HSS; 100 dyn/cm) is generated in pulmonary arteries (PAs; 100-500 µm) in congenital heart defects causing PA hypertension (PAH) and in idiopathic PAH with occlusive vascular remodeling. Endothelial-to-mesenchymal transition (EndMT) is a feature of PAH. We hypothesize that HSS induces EndMT, contributing to the initiation and progression of PAH.
View Article and Find Full Text PDFJ Endovasc Ther
November 2024
Department of Interventional Radiology, University Hospital Leuven, Leuven, Belgium.
Purpose: We described an alternative access for thoracic endovascular aortic repair (TEVAR) deployment using a transjugular intrahepatic portosystemic shunt (TIPS) needle for gaining transcaval access to the abdominal aorta.
Case Report: A 63-year-old man presented with a penetrating atherosclerotic ulcer in the descending aorta. Traditional transfemoral and transaxillary access were not possible.
Arterioscler Thromb Vasc Biol
December 2024
Vascular Biology and Therapeutics Program (W.Z., L.G., H.B., Z.L., R.T., J.L., Y.O., C.T., A.Y., B.Y., K.A.M., J.G., G.T., A.D.), Yale School of Medicine, New Haven, CT.
Background: Arteriovenous fistulae (AVF) are the preferred vascular access for hemodialysis in patients with end-stage kidney disease. Chronic kidney disease (CKD) is associated with endothelial injury, impaired AVF maturation, and reduced patency, as well as utilization. Because CKD is characterized by multiple pathophysiological processes that induce endothelial-to-mesenchymal transition (EndMT), we hypothesized that CKD promotes EndMT during venous remodeling and that disruption of endothelial TGF (transforming growth factor)-β signaling inhibits EndMT to prevent AVF failure even in the end-stage kidney disease environment.
View Article and Find Full Text PDFJA Clin Rep
August 2024
Department of Anesthesiology and Pain Clinic, Hyogo Prefectural Harima-Himeji General Medical Center, 3-264 Kamiya-Cho, Himeji, Hyogo, 670-8560, Japan.
Sci Rep
June 2024
Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, CT, USA.
Clinical outcomes of arteriovenous fistulae (AVF) for hemodialysis remain inadequate since biological mechanisms of AVF maturation and failure are still poorly understood. Aortocaval fistula creation (AVF group) or a sham operation (sham group) was performed in C57BL/6 mice. Venous limbs were collected on postoperative day 7 and total RNA was extracted for high throughput RNA sequencing and bioinformatic analysis.
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