Heart block

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Cardiac block is a disease or inherited condition that causes heart pacemaker impairment due to some kind of obstruction (or "block") in the heart's electrical conduction system. Despite the name that sounds severe, heart blocks often do not cause symptoms at all in some cases, or sometimes heart rate loss in other cases (which can cause dizziness, syncope, and palpitations), or may require a pacemaker artificial. implanted, depending on exactly where the conduction of the heart is being disturbed and how significant it is affected.

In severe cases where the heart's ability to control and trigger a heartbeat may be completely ineffective or unreliable, the heart block can usually be treated by inserting an artificial pacemaker, a medical device that provides the correct electrical impulse to trigger a heartbeat , compensate for the inability of a natural pacemaker. Therefore, heart blocks often have no effect, or mild and occasional, and non-life-threatening effects in most cases, and can usually be treated in more serious cases.

The human heart uses electrical signals to maintain and initiate a normal heartbeat to a living person; incorrect conduction can cause mild or serious symptoms depending on the location of the blockage and how severe the conduction is being blocked. Conduction is initiated by the sinoatrial node ("sinus node" or "SA node"), and then proceeds to the atrioventricular node ("AV node") which also contains a secondary "pacemaker" which acts as a reserve for the SA node, then to his bundle and then through the bundle branches to the top of the fascicular branches (shown in the diagram on the right). Therefore, the blockage is classified according to where the occurrence of blockage - ie SA node ("Sinoatrial block"), AV node ("AV block" or AVB ), and at or under his own bundle (" Intra-Hisian "or" Infra-Hisian block "respectively). Infra-Hisian blocks can occur in the left or right bundle branch ("bundle branch block") or the fascicles of the left bundle branch ("fasciculus block" or "Hemiblock"). The SA and AV node blocks are each divided into three degrees, with second degree blocks being divided into two types (written either "type I or II" or "type 1 or 2"). The term "Wenckebach block" is also used for second type 1-degree blocks of SA or AV node; in addition to second-degree blocks of types 1 and 2 are also sometimes known as "Mobitz 1" and "Mobitz 2".

Clinically, the block tends to have a more serious potential that is closer to the 'end' of the electrical pathway (the heart muscles are regulated by heart rate), and the less serious effects draw nearer to 'start' (in the SA node), because the potential for the disturbance to be greater because more 'paths' are 'blocked' from the 'end' point. Therefore, most of the important heart blocks are nodal AV blocks and infra-Hisian blocks. The SA block usually has a lower clinical significance, because in the case of the SA block, the AV node contains a secondary pacemaker that will still retain a heart rate of around 40-60 beats per minute, enough for consciousness and a lot of daily life in the majority of individuals.

Video Heart block

Jenis

Following the electrical signal path, the places where conduction can be blocked cause various types of heart block:

The SA and AV node blocks are each divided into three degrees, with second degree blocks being divided into two types (written either "type I or II" or "type 1 or 2"). In SA blocks, electrical impulses are delayed or blocked on the way to the atria, thus delaying atrial depolarization. In contrast, AV blocks occur in the AV node and delay ventricular depolarization. The term "Wenckebach block" is also used for some heart blocks, and can refer to type I block of second degree in either the SA node or AV node, but the ECG features of the two are quite different.

nodal block SA

The SA block rarely gives severe symptoms, because even if one has a complete block at the level of conduction system (which is not common), the secondary pacemaker will be in the AV node, which will light up at 40 to 60 minute beats, sufficient to maintain awareness within state of rest. However, SA blocks are capable of causing troublesome symptoms, and may also signal conduction problems elsewhere in the heart, and therefore SA blocks - albeit a lower life-threatening risk level - are still "the most common indications for pacemaker implantation heart in the United States ".

Jenis blok nodal SA meliputi:

SA node Wenckebach (Mobitz I)
SA node Mobitz II
Blokir pintu keluar SA

In addition to the above block, the SA node can be suppressed by other arrhythmias that achieve it. These include retrograde conduction of the ventricle, ectopic atrial beats, atrial fibrillation, and atrial flutter.

The difference between the SA node block and the SA node suppression is that in the SA node it blocks the electrical impulses generated by the SA node that does not make the atria contract. In SA node suppression, on the other hand, the SA node does not generate an electrical impulse as it is reset by an electrical impulse entering the SA node.

AV nodal blocks

There are three basic types of AV nodal blocks:

First level AV block
Second degree AV block
- Type I second-degree AV block (Mobitz I), also known as Wenckebach block
- Type 2 second-level AV blocks (Mobitz II) - because a block in or under the bundle
Third-degree AV block (complete heart block)

Infra-Hisian Block

Infra-Hisian Block is a distal conduction system. Types of infra-Hisian blocks include:

Type 2 of the second degree of cardiac blockbuster (Mobitz II) - a block of AV block because of blocks inside or under the bundle
- Anterior fascicular block left
- Posterior posterior fasciculus block
Right bundle branch block

From this type of infra-Hisian block, the Mobitz II heart block is considered the most important because of the possible development to complete the heart block.