Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
1
Is any of this happening now?
Call 911
Call emergency services for:
Sudden or severe difficulty breathing
Fainting, especially during exercise or with palpitations
Chest pressure or pain that is severe, persistent, or accompanied by sweating or nausea
A very fast or irregular heartbeat with weakness, chest pain, or breathlessness
Stroke signs, such as facial drooping, arm weakness, or difficulty speaking
Other emergency signs, for anyone
Someone who is struggling to breathe, gasping, choking, or cannot get words out
Someone who has chest pain, tightness or pressure lasting more than a few minutes
Someone who has sudden weakness or drooping on one side of the face or body, slurred speech, or sudden confusion
Someone who is unconscious, or cannot be woken
Someone who is bleeding heavily and it will not stop with firm pressure
Someone who has had a seizure that will not stop, or does not wake up afterwards
Someone who has lips or skin that look pale, blue, grey or blotchy
Someone who you believe has taken an overdose or swallowed something poisonous
2
Is any of this happening?
Be seen today
Seek prompt medical advice if palpitations last longer than usual, keep returning, or occur with light-headedness.
New ankle swelling, breathlessness when lying flat, or waking at night short of breath also needs timely assessment.
A fever that persists, especially with chills, night sweats, unusual tiredness, or worsening breathlessness, needs prompt medical review because it can be a sign of infective endocarditis.
3
Does any of this apply?
Book an appointment
Arrange a routine medical appointment if you develop new palpitations, mild breathlessness, chest discomfort, or a gradual reduction in your ability to exercise.
These symptoms have many possible causes and should not automatically be blamed on the valve.
Every sign above is quoted from the sofidex article on Mitral valve prolapse. If you are not sure, err upward — it is always reasonable to be checked.