The following symptoms and complaints may indicate atrioventricular block (AV block):
- 1st-degree AV block
- No symptoms (sinus node rate = heart rate).
- AV block 2nd degree
- Mobitz type I (Wenckebach block)
- Heart rate usually rhythmic with sudden pause, thus often bradycardia (< 60 beats/min) (sinus node rate > heart rate)
- Mobitz type II (Mobitz block).
- Heart rate is arhythmic (failure of a ventricular action to respond to atrial excitation without the PQ interval having previously been prolonged; in this case, only every 2nd, 3rd, or 4th atrial action may also be regularly transmitted to the ventricle (2:1 or 3:1 or 4:1 block))
- Mobitz type I (Wenckebach block)
- 3rd degree AV block (asystole/ arrest of electrical and mechanical cardiac action if no replacement rhythm occurs!).
Accompanying symptoms depending on
- Length of the break
- Nausea (sickness)
- Paleness
- Vertigo (dizziness)
- Cardiogenic shock (form of shock caused by weakened pumping action of the heart).
- Speed of replacement rhythm
- Bradycardia (heartbeat too slow: < 60 beats per minute) → cerebral underperfusion/inferior brain supply (easy fatigability, dizziness, apathy (listlessness), cognitive impairment), heart failure (cardiac insufficiency), dyspnea (shortness of breath)
If the heart is pre-damaged, the replacement rhythm of the AV node may be absent, which may lead to prolonged cardiac arrest with immediate unconsciousness.
