In patients with atrial fibrillation (AF), the atria generate as many as 500 action potentials per minute, causing the atria to spasm instead of contracting as a coordinated unit. A maze procedure involves making incisions in the atria and sewing them back together, resulting in the formation of scar tissue in the atria. How might this procedure prevent atrial fibrillation?
A. The scar tissue would isolate the atrioventricular bundle from the atrioventricular node, electrically insulting the atria.
B. Scar tissue is composed of connective tissue, which does not conduct electrical impulses. This means that action potentials in one atrium will not spread to the other atrium
C. This procedure damages the atrioventricular node, making it impossible for the atria to generate action potentials
D. The maze procedure damages the sinoatrial node, making n impossble for the atria to generate action potentials
Ans: B. Scar tissue is composed of connective tissue, which does not conduct electrical impulses. This means that action potentials in one atrium will not spread to the other atrium
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