Final answer:
Missing QRS complexes on an ECG indicate a partial heart block where only half of the P waves are followed by QRS complexes and T waves, showing an intermittent conduction problem in the heart.
Step-by-step explanation:
If QRS complexes are missing on an electrocardiogram (ECG), it indicates that there is an issue with the electrical conduction system of the heart. Specifically, when there's a mention of 'filling look like if miss QRS,' it appears to relate to a pattern where not all P waves are followed by QRS complexes and T waves. This is characteristic of second-degree or partial heart block. Half of the P waves are followed by QRS complexes and T waves, while the other half are not, denoting an intermittent failure of the atrial impulse to conduct through the AV node to the ventricles.