Recently diagnosed w/ PSVT. I underwent brain CAT Scan, heart ultrasound, ECGs, & blood testing; all were normal. Only after a Holter was PSVT diagnosed. Cause unknown and I do have blood tests scheduled to check for adrenal / thyroid problems. My heart rate is normally 60-70 BPM resting & BP 120-130 Systolic / 80-86 diastolic (w/o medication) but at times it goes to 100-130 BPM & 150-160 Systolic / 90-110 Diastolic. Sometimes I noticed it & sometimes not but Holter showed it. 1) What causes this? I have noticed if I eat too much (beyond feeling full) PSVT occurs. My BP was a little high before but is now normal even while unmedicated. I eat healthy, exercise, and in early 20s. 2) Could anxiety be the cause? I take Metoprolol (for about a week now) & my heart is 55-62 BPM. My BP is between 118-125 S and 78-82 D. 3) What is a BPM I should be concerned w/ (if my heart rate drops below *blank* BPM, seek help)? I take 50mg Meto. at 10 AM & 25mg at 10 PM. I experience an inability to get an erection. 4) Can Viagra safely be taken while on Meto. w/ my BP at 118-125 S & 78-82 D & rate at 55-62 BPM? 5) Is there another way to solve the ED while on the drug? 6) Given my dosings of 50mg and 25mg daily, what is the method to stop taking Meto.? I know you cannot stop outright but gradually decrease dosage over time until weaned off. 7) Given my dosage, what's a safe way to wean off (I will not do this until I have the ok)? 8) Will I have problems once off Meto.? I have no other heart problems & rhythms are normal even during PSVT. The PSVT was infrequent: few times monthly, if that.