what will my heart do?

Hello! Just to preface this, I am not preggo get but want to be soon. Ive talked to my doctors already about it but want to see anyone else's experience.

Last year in Nov, I was hospitalized for "sinoatrial reentry tachycardia." Basically, this means that my heart is really sensitive and my baseline heart rate is high anyway. I'm 22, and when I was in high school I was on Metoprolol for palpitations and tachycardia, but insurance changed so it was expensive and I stopped taking it after like two and a half years. Last year I was working (im an RN at a hospital) and started feeling awful, went to the ER after trying to work for 2 hours. My heart rate as 160. They gave me some IV Metoprolol that worked for 30 or so minutes, then gave me something else that accidentally made it go up to 180. So I got admitted for 3 days. Since then I've been stable on Metoprolol. Talked to my cardiologist and my family doc. Metoprolol is class C so I've come off it. My cardiologist put in a prescription for me that's safe in 2nd and 3rd tri but not first so I can't take it until 2nd tri. I've been off everything since the 19th. I've been getting really tachycardic from 2pm-4pm daily. Usually around 140heart rate as high as 160. What can I expect when I actually get pregnant? If you've had this type of experience.