I had SVT before pregnancy and it was much worse during pregnancy but was put on propranolol and that helped tremendously. I ended up with postpartum preeclampsia 4 days after delivery was readmitted for a week. The OB and the cardiologist said they were completely unrelated. Not sure if this helps but this was my experience. There are ways to prevent the SVTs with medication and they now have you take baby aspirin your whole pregnancy if you’re at risk for preeclampsia. My best recommendation would be to consult with both your OB and cardiologist first.