The purpose of this study was to determine the influence of the resistance of the terminal vascular bed of an occluded coronary artery on collateral blood flow and collateral resistance. In 6 anesthetized dogs, left anterior descending coronary artery (LAD) was ligated, cannulated, and the terminal vascular bed was occluded by latex microspheres (diameter: 25 mu). Retrograde flow was measured using a new technique, which allowed control of outflow pressure of retrograde flow (PRF) at the LAD cannula. When retrograde flow was interrupted, pressure in the occluded vessel represented collateral perfusion pressure (CPP) within the border zone of the ischemic vessel. Collateral resistance was determined dividing the pressure difference across the collateral bed (CPP-PRF) by retrograde flow. Variation of PRF was used as a model for changes in resistance of the ischemic bed. Retrograde flow fell when PRF was increased from 11.0 +/- 3.0 ml X min-1 X 100 g-1 (PRF = 0) to 8.3 +/- 2.4 (p less than 0.01)(PRF = 24.6 +/- 6 mm Hg). For the same PRF range, collateral resistance fell from 9.68 +/- 2.96 to 8.30 +/- 2.50 mm Hg X ml-1 X min X 100 g (p less than 0.01). These results indicate that the vascular resistance of the terminal ischemic bed may considerably influence collateral blood flow and resistance.
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Dokl Biochem Biophys
January 2025
Laboratory of Microangiopathic Mechanisms of Atherogenesis, St. Petersburg State University, St. Petersburg, Russia.
The aim of this study was to describe the features of myocardial lymph flow using a new combined method of visualization of the lymphatic system. The study was performed on pig hearts harvested from a local slaughterhouse. The original dye, consisting of lipid-soluble chlorophyll and lipiodol, was injected stepwise into the lymphatic vessels.
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January 2025
From the Department of Radiology (J.L., E.A.B., C.B., J.C., R.K., W.B., D.F.K), and Department of Neurologic Surgery (Y.C.S., R.K., W.B.), Mayo Clinic, Rochester, MN, United States; Department of Stroke Research (J.L.), Vall d'Hebron Research Institute, Barcelona, Spain; From the Global Institute of Future Technology (Y.L.), Shanghai Jiao Tong University, Shanghai, China; Department of Neurointerventional Radiology (J.C.), Bicetre University Hospital, Le Kremlin Bicetre, France.
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J Thorac Dis
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College of Chemistry and Life Science, Beijing University of Technology, Beijing, China.
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View Article and Find Full Text PDFAnn Pediatr Cardiol
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