What is ventricular depolarization simple?

Ventricular depolarization occurs in part via an accessory pathway (AP) directly connecting the atrium and ventricle and thus capable of conducting electrical impulses into the ventricle bypassing the AV-His Purkinje conduction system.

What happens during ventricular depolarization?

The depolarization spreads from the atrioventricular node to the septum and the walls of both ventricles through the bundle of His and Purkyne fibres. The ventricular depolarization causes the QRS complex in the ECG (fig. 1.3). At the same moment, the atria are repolarized to produce the atrial T (Ta) wave in the ECG.

What does depolarization in the heart mean?

What is meant by depolarization of the heart? Depolarization of the heart is the orderly passage of electrical current sequentially through the heart muscle, changing it, cell by cell, from the resting polarized state to the depolarized state until the entire heart is depolarized.

What is ventricular depolarization and repolarization?

Ventricular depolarization (activation) is depicted by the QRS complex, whereas ventricular repolarization is defined by the interval from the beginning of the QRS complex to the end of the T- or U-wave. On the surface ECG, ventricular repolarization components include the J-wave, ST-segment, and T- and U-waves.

What wave is ventricular depolarization?

QRS wave complex The three waves of the QRS complex represent ventricular depolarization.

What is atrial and ventricular depolarization?

Atrial depolarization is reflected by the P wave, and ventricular depolarization is reflected by the QRS complex, whereas the T wave reflects ventricular repolarization, see Figure 6.10. Atrial repolarization cannot usually be discerned from the ECG since it coincides with the much larger QRS complex.

Is ventricular depolarization the same as contraction?

Ventricular depolarization will lead to ventricular contraction and the start of systole. Remember that systole is the cardiac phase in which the heart, especially the ventricles, contracts to move blood forward into the pulmonary artery and aorta.

Is ventricular depolarization systole or diastole?

Initially, both the atria and ventricles are relaxed (diastole). The P wave represents depolarization of the atria and is followed by atrial contraction (systole).

Is depolarization the same as contraction?

Terms in this set (35) Depolarization is the same as contraction. False, depolarization occurs before contraction. If the wave of depolarization moves toward the positive electrode, the waveform recorded on ECG graph paper will be upright (+).

What causes depolarization?

Depolarization is caused by a rapid rise in membrane potential opening of sodium channels in the cellular membrane, resulting in a large influx of sodium ions. Membrane Repolarization results from rapid sodium channel inactivation as well as a large efflux of potassium ions resulting from activated potassium channels.

Why does depolarization cause contraction in the heart?

Implications of pacemaker activity on global cardiac depolarization. Synchronous contraction: all cardiomyocytes (including pacemaker cells) are electrically coupled through gap junctions. An action potential in one cell will cause all neighbouring cells to depolarize, allowing the heart chambers to act as a unit.