For patients with pheochromocytoma, when malignant pheochromocytoma occurs and leads to hypertensive crisis, it often causes severe blood pressure increases, with blood pressure even reaching over 300 mmHg. At the same time, patients present with significant symptoms such as arrhythmia, tachycardia, palpitations, and shortness of breath. Some patients may also experience prominent chest pain, labored breathing, respiratory distress, and even marked sensations of urgency or anxiety, as well as a feeling of impending doom. Additionally, some patients may experience transient vascular constriction dysfunction due to severe hypertension, leading to cerebral hemorrhage.