Firstly, the decision on the drug to treat needs to be based on the cause of the heartburn.
For asymptomatic sinus tachycardia, observation is usually the norm and no treatment is needed. In the case of atrial fibrillation and atrial flutter, amiodarone, for example, is needed to turn the heart rate around. If the heart rate is too fast, a beta-blocker is needed to slow it down. If the blood supply to the coronary arteries is inadequate, the patient needs to be given medication that is specific to coronary artery disease.