I take blood thinners and suffer from vascular and heart problems. What are the precautions I should take before the vaccine??

Even with the intake of various diluents and anticoagulants, the Astrazynx vaccine is effective and safe. You can continue with these fluids without fear or anxiety.
But what are the necessary precautions before the vaccine?
First. The doctor must be informed of this in order to take into account the use of a thinner needle to inject the vaccine (25 or 23), and the injection site must be pressed steadily for more than two minutes without moving.
The appearance of slight bleeding at the site of the injection is possible in the case of taking diluted medicines (such as aspirin or clopidogrel), and it is a simple matter that does not worry at all.
If you are taking warfarin, the dose should be fixed and the last reading to analyze the fluidity within the correct limits.
And you are well, healthy and well
Dr. Orwa Mohamed Hani El-Mally

German International Academy of Medicine and Research
Source . British Heart Association
https://www.bhf.org.uk/informationsupport/heart-matters-magazine/news/coronavirus-and-your-health/coronavirus-vaccine-your-questions-answered