Coronary flow reserve
Encyclopedia
Coronary flow reserve is the maximum increase in blood flow through the coronary arteries above the normal resting volume. Its measurement is often used in medicine to assist in the treatment of conditions affecting the coronary arteries and to determine the efficacy of treatments used.
of the coronary arteries has the ability to reduce, and this can increase the volume of blood passing through the blood vessels. This reduction occurs because the arteries dilate
, which causes an increase in the diameter of the lumen
. The greatest potential for this change is normally in the branches (arterioles) of the coronary artery that penetrate the myocardium, rather than those on the surface of the heart.
, doppler echocardiography
, and positron emission tomography
(PET).
, for example, and the measurement of CFR enables the efficacy of such interventions to be measured.
In patients suffering from Anderson-Fabry disease, there is evidence to suggest that CFR can be reduced.
When coronary flow reserve is used in medicine, it is often expressed with a numerical value, which is formed by dividing the maximal coronary blood flow by resting blood flow. This allows for an objective view, which can aid diagnosis and treatment.
Overview
When demand for oxygen in the myocardium is increased, the vascular resistanceVascular resistance
Vascular resistance is a term used to define the resistance to flow that must be overcome to push blood through the circulatory system. The resistance offered by the peripheral circulation is known as the systemic vascular resistance , while the resistance offered by the vasculature of the lungs...
of the coronary arteries has the ability to reduce, and this can increase the volume of blood passing through the blood vessels. This reduction occurs because the arteries dilate
Vasodilation
Vasodilation refers to the widening of blood vessels resulting from relaxation of smooth muscle cells within the vessel walls, particularly in the large arteries, smaller arterioles and large veins. The process is essentially the opposite of vasoconstriction, or the narrowing of blood vessels. When...
, which causes an increase in the diameter of the lumen
Lumen (anatomy)
A lumen in biology is the inside space of a tubular structure, such as an artery or intestine...
. The greatest potential for this change is normally in the branches (arterioles) of the coronary artery that penetrate the myocardium, rather than those on the surface of the heart.
Measurement
Coronary flow reserve can be measured through a variety of methods, including digital subtraction cineangiography with coronary catheterizationCoronary catheterization
A coronary catheterization is a minimally invasive procedure to access the coronary circulation and blood filled chambers of the heart using a catheter. It is performed for both diagnostic and interventional purposes....
, doppler echocardiography
Doppler echocardiography
Doppler echocardiography is a procedure which uses ultrasound technology to examine the heart. An echocardiogram uses high frequency sound waves to create an image of the heart while the use of Doppler technology allows determination the speed and direction of blood flow by utilizing the Doppler...
, and positron emission tomography
Positron emission tomography
Positron emission tomography is nuclear medicine imaging technique that produces a three-dimensional image or picture of functional processes in the body. The system detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide , which is introduced into the body on a...
(PET).
Medical implications
Coronary flow reserve is used in diagnostics and treatment of patients suffering from conditions such as coronary artery disease and syndrome X. In the treatment of these conditions, vasodilators are used to allow sufficient blood to flow past a stenosisStenosis
A stenosis is an abnormal narrowing in a blood vessel or other tubular organ or structure.It is also sometimes called a stricture ....
, for example, and the measurement of CFR enables the efficacy of such interventions to be measured.
In patients suffering from Anderson-Fabry disease, there is evidence to suggest that CFR can be reduced.
When coronary flow reserve is used in medicine, it is often expressed with a numerical value, which is formed by dividing the maximal coronary blood flow by resting blood flow. This allows for an objective view, which can aid diagnosis and treatment.