52 Years Old Man Suffering From Right Bundle Branch Block With Heart Burn. Had Also One Bypass And One Valve Replacement

Hello doc, My dad is 52 yrs old,around a week ago he complained of a burning sensation in the chest followed by weakness and when the BP was chesked it was way too low.When he got an Ecg done,docs told us he has had an attack and needs to be shiufted to ICU.Following which he was performed an angiogram ,That revealed 4 blocks,3 of which were 100% blocks and 1 was 90% block.Now he has undergone a bypass.My dad gets done ECG tests almost evry months and was detected RBBB which the docs ignored. I done understand how he might have developed such huge blocks in so less a time.Moreover he has never shown any symptoms like breathlessness , dizziness etc.He has a family history of 1 bypass and 1 valve replacement .He also smokes.Kindly explain.Alsso can you enumerate on where the blocks ould have been?