Evaluation of the Efficacy and Safety of Nifekalant Hydrochloride (NIF) Injection.

Inclusion Criteria:

• Patients with persistent ventricular tachycardia or ventricular fibrillation who havea combined physical heart disease, or who have a conventional drug ineffective orpersistent idiopathic ventricular tachycardia with amiodarone indications;

• Age ≥ 18 years old, gender is not limited.

Exclusion Criteria:

• Patients with prolonged ventricular tachycardia with QT interval and patients with QTcinterval of more than 500 ms before administration;

• Patients with torsades de pointes (Tdp);

• Patients with Brugada syndrome;

• Patients with severe atrioventricular block and without pacing protection;

• Patients with hypertrophic cardiomyopathy (HCM) with ventricular septal thickness or (and) left ventricular wall ≥ 15 mm;

• Pregnant or lactating women;

• Patients who are not suitable for the study, considered by investigators.