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:
Severe breathing difficulty, especially at rest
Fainting or collapse
Chest pain that is severe, persistent, or accompanied by sweating or nausea
A sustained rapid heartbeat with dizziness, weakness, or breathlessness
Signs of stroke, such as facial drooping, arm weakness, or speech difficulty
Do not drive yourself to emergency care if you are faint, severely breathless, or having possible stroke or heart attack symptoms.
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
Contact your heart team promptly if established symptoms noticeably worsen, your weight rises quickly with swelling, you become short of breath at rest, or you receive an alert or shock from an implanted heart device.
3
Does any of this apply?
Book an appointment
Arrange a routine medical review if you develop gradually increasing breathlessness, ankle swelling, tiredness, palpitations, or reduced exercise ability.
Also seek routine assessment if a close relative has been diagnosed with dilated cardiomyopathy or an associated genetic variant, even if you feel well.
Every sign above is quoted from the sofidex article on Familial dilated cardiomyopathy. If you are not sure, err upward — it is always reasonable to be checked.