Blood tests are standard for anyone who follows doctor's advice and has a checkup once a year. The blood is an excellent indicator of what is going on inside of the body, and carries markers for several diseases, just like many other tests performed on a routine basis.
There are parameters that indicates if you are reducing your risk of another HA (like cholesterol), and others that can be used to detect failures in kidneys and liver due to medication and others to check that you are not loosing critical mineral for your heart to work (Sodium and Potassium).
Those are about the minimum assuming that you have not suffered major damage in your heart.
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