A 37-year-old patient complains of throbbing headache in the frontal region, frequent episodes of nausea, palpitations, and elevated blood pressure of 240/140 mm Hg. According to the patient's medical history, two days ago she experienced an episode of debilitating headache, palpitations, pulsation of blood vessels, dyspnea, and fear of approaching death. At that time, her face became pale and her hands and feet became sweaty. After examination, elevated levels of metanephrines were detected in the patient's urine. What is the most likely diagnosis in this case?