Are you currently covered, and thinking of a change? Have you had any gaps in your coverage?
If you aren't covered at all, generally the Blue Cross/Blue Shields will cover even those with pre-existing conditions.
If you are covered and looking at a change, you may have rights under a federal law called HIPAA, that guarantees access to insurance.
go work for a company that has group health insurance. some state allow you to start a company with 2 employees to have guaranteed group health insurance.