Does a brain attack necessarily mean high blood pressure?

There are many patients with cerebral infarction who do not necessarily have high blood pressure, mainly in the following cases, no cerebral infarction can also cause high blood pressure: First, coronary heart disease myocardial infarction, wind heart disease, long-term arrhythmia, atrial fibrillation or heart valve surgery, it is easy to form a thrombus in the atrium, and after the thrombus is dislodged, it is easy to cause cerebral embolism caused by blockage of blood vessels in the brain. Secondly, if a hypotensive patient has high fever, insufficient food or a large amount of diarrhea caused by insufficient blood volume, it is also easy to cause a decrease in blood pressure and a sudden cerebral infarction. Third, for young female patients, if they are taking oral contraceptives for a long time, it can also cause changes in blood viscosity and blood stagnation and cerebral infarction. The above three cases are all patients without hypertension have a cerebral infarction.