EP Practice Lab · Case 3 of 12
Coronary Sinus Activation Sequence
Interpret an illustrative distal-to-proximal atrial activation pattern without overcalling mechanism.
Question
What is the safest conclusion from the displayed CS sequence?
Practice Lab principle
Describe what you observe first. Then connect the observation to mechanism, troubleshooting, or next-step reasoning. Avoid jumping from one clue to a final diagnosis.
Educational scope: All cases are synthetic and simplified. They are designed for conceptual practice, not clinical decision-making or independent procedural guidance.