Refractory hypertension is a difficult problem in the treatment of hypertension. With an aging population and the increase in obesity, sleep apnea hypoventilation syndrome, and chronic kidney disease, RH is becoming an increasingly common clinical problem. Poor blood pressure control can lead to target organ damage such as heart, brain and kidney, thus promoting the occurrence of clinical vascular events, and actively and effectively bringing blood pressure up to standard is an important part of hypertension treatment. 1, the definition of RH On the basis of improving lifestyle, the application of a reasonable tolerable amount of adequate ≥ 3 antihypertensive drugs (including diuretics) treatment > 1 month blood pressure still does not reach the standard, or take ≥ 4 antihypertensive drugs to effectively control, known as RH. 2, the epidemiology and prevalence of RH At present, there is no accurate epidemiological data, according to relevant data presumed that the prevalence of RH is 5%-30%. 3.The etiology and pathophysiological mechanism of RH The etiology and pathophysiological mechanism of RH are various. There are basic etiologies, as well as central and local neurohumoral mechanisms. Studies have shown that enhanced and sustained sympathetic as well as RAAS activity is one of the important pathogenic mechanisms, and multiple factors combine to influence sympathetic as well as RAAS activation. The kidney has an important role in the pathogenesis of RHD. Among them, local sympathetic over-activation in the kidney is one of the pathogenetic bases of RH and an important pathophysiological mechanism. 4, Diagnostic methods of RH Blood pressure measurement as the main diagnostic tool, it is recommended that newly diagnosed hypertensive patients for 2 consecutive weeks, and patients with significant blood pressure fluctuations for 3-7 d, 2 times in the morning and 2 times in the evening (in the morning before taking medication and in the evening at least 12 h after taking medication in the morning or before going to bed) for home self-measurement of blood pressure, each time 3 times, and calculate the average of the closest 2 times. Patients are advised to bring their electronic sphygmomanometer to the clinic for measurement in order to check the patient’s measurement technique and the accuracy of the instrument (compared with a desktop mercury sphygmomanometer).