Atrioventricular block (AVB) is a cardiac arrhythmia in which there is a disturbance in the conduction of the electrical stimulus between the different chambers of the heart, atria and ventricles. In second-degree AVB, one or more atrial stimuli are not conducted to the ventricles (not all P waves are followed by QRS on the electrocardiogram).
There are two types:
- Type I - Mobitz I or Wenckebach.
- Type II - Mobitz II
In second-degree AVB Mobitz II there is an intermittent block of the electrical stimulus generated in the atria that do not lead to the ventricles.
The most frequent cause is the lack of coronary irrigation to the myocardial cells, called ischemic heart disease.
It manifests with weakness, shortness of breath, chest pain, loss of consciousness and sudden cardiac arrest.
Diagnosis is based on clinical examination and physical examination. It is confirmed with an electrocardiogram showing an electrical conduction block.
In symptomatic cases, the patient should be stabilized with medication that accelerates the heart rate. If symptoms are severe or the arrhythmia causes organ failure, urgent pacemaker placement is recommended until definitive pacemaker placement.
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