This part of the Simplified in Practice series explains ECG characteristics of complete heart block along with its possible causes. Additionally, a simplified explanation of AV blockages on the ECG is included in the article.
Complete heart block is characterised by the lack of AV conduction, with no supraventricular impulses reaching the ventricles. Junctional or ventricular escape rhythms sustain the perfusing beat. Alternately, the patient may have a ventricular standstill that results in syncope (if self-terminating) or abrupt cardiac death (if prolonged).
Electrocardiogram (ECG) characteristics of complete heart block
- Severe bradycardia because AV conduction is absent.
- The electrocardiogram reveals full AV dissociation, with separate atrial and ventricular rates.
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