@jolly said in Pacemaker:
https://nypost.com/2021/04/15/former-vp-mike-pence-recovering-after-receiving-a-pacemaker/
From the article:
"Pence disclosed his medical history when he was nominated for vice president in 2016, including the diagnosis of asymptomatic left bundle branch block, the statement said."
A left bundle branch block will not require a pacemaker. The electrical stimulus to the ventricles arises from the AV (atrial-ventricular) node. From there, the stimulus travels via two bundles of conductive tissue - one to the right ventricle, and one to the left ventricle. The one to the left ventricle bifurcates into anterior and posterior portions. The fact that he had a LBB indicates that the sick part of the bundle is before that bifurcation.
Many people live with asymtomatic LBBB, and most don't even know it. The major physiologic effect of it is that the right and left ventricles don't contract at the same time (perhaps 120 milliseconds apart). With a LBBB, the stimulus goes down the right bundle, and then has to go back up the left ventricle - it takes a detour. Since the stimulus is going retrograde up the LV, the efficiency of the LV contraction is not as good as it could be.
The fact that he required a pacemaker indicates that his disease progressed, probably to the point that no signal was getting past the AV node, and it started firing on it's own (it'll do that if not stimulated from above, in the atria), but at a slower rate - usually in the 40s or 50s.
This is more than you wanted to know, of course, but I just find this kind of stuff fascinating.
https://www.verywellhealth.com/left-bundle-branch-block-lbbb-1745784
Is a Permanent Pacemaker Required?
Unless there is a reason to insert a CRT pacemaker to re-coordinate the function of the ventricles, most people with left bundle branch block never require a pacemaker.1 However, in some cases, the presence of left bundle branch block indicates a more general disorder of the cardiac electrical conducting system.
In such people, the heart's electrical signal can become disrupted in several ways, and significant bradycardia (slow heart rate) may eventually develop, and a permanent pacemaker might be required.11 For this reason alone, people with left bundle branch block should make sure they have regular medical checkups.
