Sand should be part of the topdressing used to topdress your field after aerating and before overseeding. However, this section on sand is for a different use of sand. Sanding the baseball field turf, especially the infield, is a good practice.and should be part of the topdressing used to topdress your field after aerating and before overseeding. However, this section on sand is for a different use of sand. Sanding the baseball field turf, especially the infield, is a good practice.
Atrioventricular (AV) Block. A slow heart rate can be due to many causes, including the earlier described sick sinus syndrome (SSS). Another cause, atrioventricular block (AV block), is due to abnormally slowed electrical conduction of the sinus impulse through the AV node.
Conduction block: The electrical pathway may also be blocked near the AV node, in between the atria and ventricles. A conduction block doesn't completely stop the heartbeat because another set of cells in the AV node or ventricles act as a secondary pacemaker. When this backup system goes into effect, the heartbeat is slower than when it is regulated by the SA node, which serves as the atrial pacemaker.