People with high blood pressure can have circulatory problems & sitting in a cramped plane seat can lead to the development of deep vein thrombosis. To decrease the risk wear flight socks to improve circulation and walk up and down the aisles regularly do not forget to request an aisle seat. Stretch and move around in your seat as much as is possible, avoid alcohol and drink plenty of water to stay hydrated.
Don't forget to keep your medication in your hand luggage but make sure you comply with current airport security procedures contact your departure airport and airline for information.
When you arrive at your destination try not to over indulge and remember your good habits from home. Avoid prolonged exposure to cold temperatures as this causes the blood vessels to constrict in an attempt conserve body heat, so increasing heart rate and blood pressure, and therefore increasing the likelihood of heart attack or stroke. Take a jumper out with you in the evening even if it has been a hot day. Don't travel to high altitudes as there is less oxygen in the air and this could aggravate your condition.
Stay relaxed while away by being organised and planning ahead. Leave plenty of time to travel to and from airports and hotels. Avoid lifting heavy luggage, luggage with wheels is recommended.
Be mindful that being at high altitude forces the heart to work harder and raises blood pressure, so be sure to consult your doctor prior to travel.