Cardioplegia, also known as propafenone, has an oral minimum maintenance dose of roughly 300mg and an intravenous minimum maintenance dose at 70mg. Clinically, it is mainly used for paroxysmal ventricular tachycardia and supraventricular tachycardia, prevention of supraventricular tachycardia, atrial flutter or atrial fibrillation in people with preexcitation syndrome, and the treatment of various types of premature beats. cardioplegia is well-absorbed in gastrointestinal tract and eliminated through dual pathways of the liver and the kidneys, and the plasma concentration reaches the peak in 2 to 3 hours after taking it. Oral maintenance dose of 300-600mg per day, the minimum maintenance dose of 300mg, divided into 2-4 times. Note that propafenone should be swallowed with a drink or food after a meal and should not be chewed. Intravenous minimum maintenance dose of 70mg, each time 70mg diluted with 5% dextrose solution, injected slowly over 10 minutes; if necessary, repeat 1 time in 10-20 minutes, the total amount does not exceed 210mg. IV push followed by IV drip (to maintain therapy) at a drip rate of 0.5 to 1 mg/min. Adverse effects such as dizziness, headache, dyskinesia, and metallic taste in the mouth can occur with cardioplegia and can cause worsening of congestive heart failure. Propafenone is contraindicated in patients with severe hypotension, myocardial ischemia in coronary artery disease, myocardial infarction, as well as in those who are allergic to propafenone. In summary, if you need to use this drug, you should strictly follow the doctor’s instructions for use, do not blindly use the drug, specific medication, treatment, please refer to the doctor’s interview guidance.