What is this instrument for (at the arrow) ?    

What is this instrument for?  

What is this instrument for (at the arrow) ?    

Out of the three conditions shown below, which would mostly likely have the highest blood pressure and heart rate?

Identify the arrhythmia shown in B (be specific). .  

Identify the indicated structure in  blue (include left or right as appropriate).  

Identify the indicated structure  in RED (indicate left or right).

Identify the arrhythmia shown in B (be specific). .  

Identify the indicated structure  in RED (indicate left or right).

Name the indicated region of the heart.