Question: what does it mean when your heart rate jumps up and down?
Answer: An episode of supraventricular tachycardia (SVT) occurs when abnormal electrical impulses suddenly start in the upper chambers of the heart, and override the heart's natural rhythm. SVT is sometimes called paroxysmal supraventricular tachycardia (PSVT). Paroxysm means a sudden temporary disturbance of heart rhythm.