Sympathetic hyperactivity is a causal or a promoting factor in many diseases, under these conditions, some morphology changes due to the hyperactivity occur. Renal nerve is an important part in the autonomic nervous system regulation, especially in cardiovascular system, the modulation of the renal nerves used as a therapeutic strategy has been researched across the world. The purpose of this study is to evaluate and quantify the morphology changes in different diseases, make the modulation therapy more selective and effective.

People eligible for this study will be divided into 4 groups according to the eligibility criteria(Resistant Hypertension Group,Essential Hypertension Group, Chronic Heart Failure Group and Control Group), about 15 objects for each, totally 60 objects are going to be recruited.

Before the intravascular ultrasound examination, ambulatory blood pressure, ECG, plasma catecholamine hormones, renin-angiotension-aldosterone, ect. will be measured. An intravascular ultrasound examination will be taken after all of these have been done.

Inclusion Criteria:

1. Resistant hypertension group

   • blood pressure remains above goal in spite of the concurrent use of three or more anti-hypertensive agents(including a diuretic) at adequate doses.
   • agrees to have the study procedure(s) performed and additional procedures and evaluations

2. Essential hypertension group

   • systolic blood pressure ≥ 140 mmHg, diastolic blood pressure ≥ 90 mmHg, or current use of anti-hypertensive medication with a normal blood pressure or mean ambulatory blood pressure during the 24-hour≥130/80 mmHg.
   • not resistant to pharmacotherapy.
   • agrees to have the study procedure(s) performed and additional procedures and evaluations

3. Chronic heart failure group

   • New York Heart Association class II-III symptoms, or American College of Cardiology(ACC) / American Heart Association(AHA) heart failure classification B-C class of chronic heart failure.
   • currently or prior have the signs of heart failure, such as elevated jugular venous pressure, peripheral edema, pulmonary crepitations, ect.
   • Systolic left ventricular dysfunction as assessed by echocardiogram with left ventricular ejection fraction < 40%.
   • agrees to have the study procedure(s) performed and additional procedures and evaluations

4. Control group

   • no history of arterial hypertension, heart failure and diabetes
   • going to take a vascular interventional examination during hospitalization
   • agrees to have the study procedure(s) performed and additional procedures and evaluations

All patients have full capacity for civil conduct and agree to sign the Medical Informed Consent.

Exclusion Criteria:

• hemodynamically or anatomically significant renal artery stenosis.
• renal artery variation.
• renal artery diameter < 4 mm, trunk length < 20 mm.
• secondary hypertension with known causes and pseudo-hypertension.
• has experienced myocardial infarction, unstable angina pectoris, or cerebrovascular accident within 6 months.
• has an implantable cardioverter defibrillator (ICD) or pacemaker.
• requires respiratory support.
• is pregnant or planning to be pregnant.
• cardiovascular diseases with sever hemodynamic disorder.
• type 1 diabetes mellitus.
• currently enrolled in another investigational drug or device trial.
• civil disability or limited capacity for civil conduct.
• other conditions researchers considered unsuitable for enrolled in the trial.

Hospitalized patients who are going to take a vascular interventional examination.