What Causes Elevated Blood Pressure In A Heart Patient?

I saw my primary care today. My blood pressure was taken 4 different times because the reading had such a wide spread as he doctor put it. It was 176 over 40 He did speak with my cardiologist on the phone for the ok to let me go home and not the hospital. The card. said it s ok and to make an appt. to see him asap for an echocardiogram. I do have a heart murmer, cardiomyapathy and a pace maker. What could possibly cause my bp to be so strange and how concerned should I be? I know that sounds bad, but trying to put it straight.