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.
First-degree heart block means that impulses are moving through the AV node too slowly. 1  Second-degree heart block means that impulses are traveling through the heart's atria but are delayed in the AV node. Because of this delay, the ventricles do not beat at the right moment.