I am a mild mvp patient, every time I wakeup in the morning my mouth is filled with saliva, today my mouth is filled with blood. Is these too related?

Unusual. Probably unrelated. Check with dentist or oral regarding salivary glands , infections, etc. Bleeding site likely in mouth! any sore spots, tongue bitten? Bad tooth/ teeth? Unlikely to relate to heart unless florid heart failure?
Not related to MVP . You may have bit your tongue or have bruxism.