Which rhythm is often recognized by huge dips after the QRS complex?

The rhythm characterized by significant dips after the QRS complex is often associated with a complete heart block, known as a third-degree AV block. In this condition, the electrical signals from the atria do not properly conduct to the ventricles, resulting in a dissociation between the atrial and ventricular rhythms. This leads to the QRS complexes occurring at a slower and often irregular rate, generating the notable dips or pauses after each QRS.

The dips can be particularly pronounced because the atrial activity continues independently while the ventricles beat based on their escape rhythm, creating a situation where one might see irregular pacing. This pattern can lead to significant bradycardia and symptoms such as dizziness or syncope due to reduced cardiac output.

In contrast, other conditions such as ventricular fibrillation show chaotic, irregular electrical activity without recognizable QRS complexes, which is not consistent with dips occurring after them. Myocardial infarction might cause ST segment changes but does not typically feature consistent large dips after the QRS. Lastly, atrial flutter presents a characteristic "sawtooth" pattern in the atrial activity but does not lead to the significant dips after the QRS complex seen in a third-degree AV block.