High blood pressure. High blood pressure (hypertension) is by far the most important risk factor for CVD. If your blood pressure is too high, it can damage your artery walls and increase your risk of developing a blood clot.igh blood pressure. High blood pressure (hypertension) is by far the most important risk factor for CVD. If your blood pressure is too high, it can damage your artery walls and increase your risk of developing a blood clot.