When the systole pressure is greater than 180 that is considered a high risk for a stroke. The high pressure can burst the small vessels of the brain causing a stroke so it is necessary to seek immediate treatment to lower the blood pressure.
Thanks for sharing you wife's medical concerns on this forum, and even though there may not be any symptoms, medical attention is necessary. Take care and keep us informed.
More than be concerned you need to get her to an emergency room immediately for this type of blood pressure ...she is at a high risk of having a CVA or stroke and that is not a good thing at all....that is a very dangerous blood pressure and it needs to be monitored....i would take her to the E,R, immediately if you are still getting those readings. Do not take chances with her life it is like playing Russian Roulette with a blood pressure that high.............good luck to you both......