What is the conduction velocity of the heart?
Cardiac conduction velocity is the velocity at which a depolarization wave moves through the myocardium, the muscular middle layer of the heart, and it’s measured in meters per second.
What determines conduction velocity in the heart?
Because conduction velocity depends on the rate of tissue depolarization, which is related to the slope of phase 0 of the action potential, conditions (or drugs) that alter phase 0 will affect conduction velocity.
What does the internodal pathway do?
The internodal pathways are the primary source of the transmission of signals from the sinoatrial node and the atrioventricular node. The signals from the sinoatrial node also travel to the interatrial pathway to connect the other atrium and the cardiac muscles.
What has the fastest conduction velocity in the heart?
Cells within the sinus node have the fastest rate of spontaneous depolarization, and, therefore, the sinus node is the main pacemaker region of the heart. The AV node has the second fastest rate of spontaneous depolarization, which allows it to create an escape rhythm if the sinus node is diseased.
How do you calculate conduction velocity?
The conduction velocity of the action potential is determined by measuring the distance traveled (length of the nerve in m) and dividing by the time (sec) taken to complete the reflex arc, also called the latency. Conduction velocity = distance (m)/time (sec).
Where is Bachmann’s bundle?
left atrium
In the heart’s conduction system, Bachmann’s bundle (also called the Bachmann bundle or the interatrial tract) is a branch of the anterior internodal tract that resides on the inner wall of the left atrium.
What are Internodal Fibres?
The interatrial or internodal conduction tracts are bands of specialised myocytes which are believed to lie between the sinuatrial node and the atrioventricular node. Previously, conduction between the two nodes was thought to occur through direct stimulation and conduction between normal atrial myocytes.
What are the 3 Internodal tracts?
Electric impulses are generated in the sinoatrial node (located superiorly in the right atrium at the junction with the superior vena cava) and the conduction of depolarization waves from the sinoatrial node across the right atrium to the atrioventricular node occurs through three internodal tracts, the anterior, the …
Which part of the heart has the slowest conduction velocity?
the A-V node
The atrio-A-V nodal junction is the region of lowest safety factor and slowest conduction velocity (about 0.05 M./sec.). The conduction velocity within the A-V node is about 0.12 M./sec.
Why is conduction velocity slowest in AV node?
In part, the slow conduction velocity of the AV node is the result of the small diameter of nodal myocytes (conduction velocity is function of cell diameter) and the complex arrangement of the myocytes (nodal myocytes can be separated by extensive connective tissue), which is expected to slow conduction, because the …
How do you calculate conduction?
The equation for conduction tells us that the rate of heat transfer (Q/t) in Joules per second or watts, is equal to the thermal conductivity of the material (k), multiplied by the surface area of the objects in contact (A), multiplied by the difference in temperature between the two materials (T2 – T1), divided by the …
What is meant by conduction velocity?
Also called an electroneurography, EneG, or nerve conduction study, a nerve conduction velocity (NCV) test is a measurement of the speed of conduction of an electrical impulse through a nerve. NCV can determine nerve damage and destruction.