I've been having episodes of heart palpitations and shortness of breath. It usually comes on either when I'm nervous , afraid , or when I have low blood
sugar. ( I have reactive hypoglycemia) . Anyway, I had an episode last night that showed up at random. It consisted of fast rapid heart rate, body chills, shortness of breath, and intense fear. could this be anxiety? Or perhaps another explanation. Maybe supraventricular tachardyia? symptoms last usually 10 to 30 minutes. sometimes bit longer