Related Experiment Video
Updated: Jun 4, 2025
O-Ring Aortic Banding Versus Traditional Transverse Aortic Constriction for Modeling Pressure Overload-Induced Cardiac Hypertrophy
Published on: October 6, 2022
The global effect of aortic coarctation on carotid and renal pulsatile hemodynamics
Deniz Rafiei1, Niema M Pahlevan1,2
1Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, California, United States of America.
Insights
Coarctation of the aorta (CoA) increases harmful blood flow and energy to the brain. However, it reduces blood flow and energy to the kidneys, impacting end-organ health.
Area of Science:
- Cardiovascular Physiology
- Biomedical Engineering
- Medical Devices
Background:
- Coarctation of the aorta (CoA) is a congenital narrowing of the aorta with high mortality if untreated.
- Previous research focused on local hemodynamic effects, neglecting global impacts on end-organs.
- Clinical observations suggest coarctation may damage brain and kidney hemodynamics.
Purpose of the Study:
- To investigate the mechanisms of altered wave dynamics in coarctation of the aorta.
- To assess the impact of coarctation on pulsatile hemodynamics in end-organs (brain and kidney).
Main Methods:
- Utilized a physiologically accurate in-vitro experimental setup simulating systemic circulation.
- Conducted experiments across varied cardiac outputs, heart rates, and coarctation degrees.
- Employed aortas with a wide range of stiffness to simulate diverse patient conditions.
Main Results:
- Coarctation of the aorta significantly increases cerebral blood flow and pulsatile energy transmission to the brain.
- Conversely, renal blood flow and pulsatile energy transmission to the kidneys are reduced in coarctation.
- These hemodynamic changes were observed across all tested levels of aortic stiffness.
Conclusions:
- Coarctation of the aorta alters systemic hemodynamics, leading to differential effects on brain and kidney blood flow and energy transmission.
- Increased pulsatile energy to the brain may contribute to neurological complications.
- Reduced renal blood flow and energy in coarctation could underlie kidney damage.
Abstract:
Coarctation of the aorta (CoA) is a congenital disease characterized by the narrowing of the aorta, typically the descending portion after the left subclavian artery. If left untreated, by the time individuals reach 50 years of age, the mortality rate can reach 90%. Previous studies have highlighted the adverse effects of CoA on local hemodynamics. However, no study has investigated the global hemodynamic effects of CoA in end-organ (brain and kidney) damage. Clinical studies have shown that coarctation acts as a reflection site, potentially damaging the hemodynamics of the brain and kidneys. Our goal in this study is to investigate the underlying mechanisms of these altered wave dynamics and their impacts on the pulsatile hemodynamics of end-organs. In this study, we use a physiologically accurate in-vitro experimental setup that simulates the hemodynamics of systemic circulation. Experiments are conducted across various cardiac outputs, heart rates, and coarctation degrees using aortas across a wide range of aortic stiffnesses. Our principal finding is that CoA increases cerebral blood flow and harmful pulsatile energy transmission to the brain. Conversely, both renal blood flow and pulsatile energy transmission to the kidneys are reduced in CoA at every level of aortic stiffness.
Related Concept Videos
01:16Pulse
The pulse serves as a clinical...
01:19Cardiac Output I:Effect of Heart Rate on Cardiac Output
Cardiac output (CO) refers to the total amount of blood ejected by one of the ventricles in liters per minute (L/min). In a resting adult, CO ranges from 5 to 6 L/min, adjusting according to the body's metabolic requirements.
Effect of Heart Rate on Cardiac Output
Cardiac output adapts to metabolic demands during stress, physical activity, or illness. The autonomic nervous system regulates heart rate via the sinoatrial node. The parasympathetic nervous system decreases heart...
01:18Hypertension and Regulation of Blood Pressure
01:17Autoregulation of Blood Flow
Chemical Signaling in Autoregulation
Chemical signaling operates at the precapillary sphincter level, inciting either contraction or relaxation....
01:17Measurement of Blood Pressure
01:18Neural Regulation of Blood Pressure
Baroreceptor Reflex
Baroreceptors, located in the carotid sinuses and aortic arch, detect changes in blood pressure. When blood pressure rises, these stretch-sensitive receptors...