Question

During A-Fib no single impulse completely depolarizes both _____, so there are no ____ waves, just rapid series of tiny, erratic spikes on EKG.

Answer 1

During atrial fibrillation, the lack of coordinated impulses to the atria leads to the absence of P waves on an EKG, presenting as erratic spikes rather than the regular P-QRS-T pattern associated with normal heart rhythm or specific types of heart blocks.

Step-by-step explanation:

During atrial fibrillation (A-Fib), no single impulse completely depolarizes both atria, so there are no P waves, just rapid series of tiny, erratic spikes on an EKG. The P wave represents the depolarization of the atria, and without a coordinated depolarization during A-Fib, these waves are absent. Such ECG abnormalities reflect the erratic electrical activity that characterizes this condition, distinguishing it from the regular pattern seen in normal sinus rhythm or different types of heart blocks, such as second-degree block or third-degree block. In contrast to A-Fib, with a third-degree or complete block, there is no correlation between the atrial activity (P wave) and the ventricular activity (QRS complex). Atrial fibrillation is just one of many potential ECG abnormalities stemming from various forms of cardiac arrhythmias.