heart rhythm and meds

Hi about 2 weeks ago my heart just started to race and was having trouble breathing went to er my bp was 171/121 they kept me over night and doc  at er said to not keep taking the zestril i was allready on for my bp and put me on metoprolol 50 mg by the end of the next week i felt i couldent breathe went back to er another doc put me back on zestril 20mg twice a day and hctz 25mg once a day then after few days again felt couldent breathe also each time seemed my heart pounded some then my doc ck my heartbeat said he heard a clicking sound and swooshing sound said i might have mvp and put me on 1 zestril 20mg metoprolol 25mg and hctz 25mg and set me up for a cardiagram which i had today but havent heard anything yet on it anyways while taking all of the meds over the weekend my bp dropped to low once was 91/54 so i only took half of the zestril and the hctz and third of the metoprolol and doc said to go ahead taking them like that until he gets results from the cardiagram can anyone tell me why my heart seems to be beating to hard? can mvp cause that or is the meds causing it.