The investigators will compare the effects of PSGB(percutaneous stellate ganglion block) in patients with recurrent sustained VT(ventricular tachycardia)/VF(ventricular flutter) in spite of appropriate medical therapy and cardio-version/ defibrillation after correction of underlying correctable factors with those without PSGB by prospective randomized trail. PSGB(percutaneous stellate ganglion block) will be performed every 3 days by anesthesiology specialist after cardiologist's request, until the stabilization of VT(ventricular tachycardia)/VF(ventricular flutter). We will compare the frequency and episode number of VT(ventricular tachycardia)/VF(ventricular flutter), procedure related complication, acute and long-term mortality.

Treatment

1. Research registration for medically refractory ventricular tachycardia
2. Treatment of Antiarrhythmic drug in both the experimental group and the control group
3. In addition, the experimental group implements percutaneous stellate ganglion block.

< Study Arms >
•Experimental : Antiarrhythmic drug + percutaneous stellate ganglion block
•Active Comparator : Antiarrhythmic drug group

4. Treat according to assigned group
5. Additional treatments are performed three days after the implementation of the percutaneous stellate ganglion block.
6. Continuous ECG monitoring and ICD interrogation during post-procedure hospitalization
 - Evaluation of the frequency of continuous ventricle tachycardia and ICD shock + anti-tachycardia pacing (ICD-insert patient) after treatment begins
7. Evaluation of the frequency of death and persistence of tachycardia and ICD shock + anti-tachycardia pacing (ICD-insert patient) in each group thereafter
8. Outpatient tracking after discharge
 - Assess all side effects that occur in each group

Arm Label

Target Number of Participant

Arm Type

Arm Description

◦Drug: Antiarrhythmic drug
◦Procedure: percutaneous stellate ganglion block (PSGB)
 - The subjects of this study were in a highly unstable blood flow condition and therefore difficult to move to the treatment room, making it the most likely to be conducted a method of the percutaneous stellate ganglion block for ultrasonography in bedside under these clinical circumstances.
The percutaneous stellate ganglion block is performed in the cardiac intensive care unit where can monitor blood pressure, pulse, oxygen saturation, body temperature, and electrocardiogram on experienced and skilled anesthesia pain medicine specialists.

Arm Label

Target Number of Participant

Arm Type

Arm Description

It's a drug treatment group that takes antichromatic drugs.

Gender

Age

Description

1. Over 19 years old or The legal age at which consent for the target can be provided under national law.
2. Patient are diagnosed Refractory Ventricular tachycardia
 - Patients who have generated Refractory Ventricular tachycardia despite of defibrillation and drug therapy
 - Patients with ICD have generated ICD shock or anti-tachycardia pacing despite of defibrillation and drug therapy

1. Patients who do not agree with study inclusion
2. Patients who do not taken stellate ganglion block due to unstable hemodynamic status
3. Patients have experienced major hemorrhagic complication
4. Patients of the DNR(do not resuscitate) status
5. Patients with malignancy tumor, major neurogenic disease or gastrointestinal disease

Comparison of frequency changes in persistent ventricular fibrillation that occurred 24 hours before and after treatment began in each group.

24 hours before and after treatment begins

Comparison of Frequency Changes in persistent ventricular fibrillation in 5 Days  in each group

5 days after randomization

mortality

on discharge, 1 month and 1 year after the discharge,

For ICD(implantable cardioverter defibrillator) patients, anti - tachycardia + shock occurrence and frequency

at every visit after treatment

major complication related to stellate ganglion block.

after treatment