There does appear to be a prolonging PR interval before some dropped beats (second degree type I AV ... (2:1 AV block). Note the irregular R-R intervals making 3rd degree heart block unlikely.

In second-degree type II AV nodal block (a.k.a. Mobitz Type II AV block), the AV node becomes completely refractory to conduction on an intermittent basis. For example, three consecutive P waves ...

Bradycardia is a condition characterized by a slower than normal heart rate. While a normal adult heart beats between 60 and ...

The first is the least serious and you may not have symptoms. A second degree heart block sometimes causes troublesome symptoms that need treatment and a third degree heart block is the most serious.