Within a year of being diagnosed with PMR I complained of exercise intolerance. My PCP took it seriously and ordered an exercise tolerance test which was interpreted as normal.

Sometime during my second year on Prednisone I noticed that my pulse was irregular. My PCP ordered an EKG which documented an arrhythmia and left ventricular hypertrophy (LVH). Uncontrolled high blood pressure is the usual cause of LVH. My PCP told me to check my blood pressure frequently even though I didn't have any history of high blood pressure.
https://www.mayoclinic.org/diseases-conditions/left-ventricular-hypertrophy/symptoms-causes/syc-20374314
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It didn't take me too long to get a blood pressure reading of 210/110 but I thought my little blood pressure machine was inaccurate. Fortunately I worked at a hospital so I asked some nurses to check my blood pressure. They got blood pressure readings in excess of 200/100 and took me to the emergency room. Before long, 3 blood pressure medications were started for uncontrolled blood pressure.

I took those blood pressure medications for 10 years until the I was able to taper off Prednisone. Within a year of coming off Prednisone, low blood pressure readings were being recorded. One by one my blood pressure medications were stopped. Within 2 years of discontinuing Prednisone, I was off all my blood pressure medications.

Anyone on Prednisone should be checking their blood pressure frequently. Elevated blood pressure is sometimes asymptomatic. until heart damage occurs.
https://connect.mayoclinic.org/discussion/prednisone-and-cardiac-symptoms/