Medical Mystery, Something Broke?
I am hoping to tap into the collective wisdom of forum members on a perplexing problem.
Background: I am 66 yrs old, fairly active; exercising for 3-4 days a week by walking 3-5 miles at a time. I had a complex set of symptoms that delayed diagnosis until I saw an EP doc. I had brachycardia and sick sinus syndrome; in addition I had cervical spinal stenosis affecting innervation of my respiratory muscles, resulting in low oxigenation at rest and on exercise.
I had the PM (Medtronic Azure XT) implanted on Dec. 7, 2018, and set to pace resting HR 60 bpm and highest rate of 155, and am pacing 95% of the time. Prior to surgery I asked the EP doc if they could put the PM more medial to avoid my backpack shoulder straps rubbing on the implanted device. In post-op the EP doc informed us that due to the location of the pump he could only place the atrial lead, so I am pacing only the atria. I still could not exercise until I had cervical spine decompression and fusion performed Jan. 23rd 2019. After I recovered I began exercising, and was getting my HR up to 151 bpm when I exercised. My pulse Ox ranged from 95-98%. Exercise felt great, and I regained my energy with no fatigue. Everything was great.
In early April my energy decreased and I felt fatigue in the late afternoon, My excercise tolerance began decreasing, and by the middle of May it was difficult to walk 1 mile. My bp also had increased in spite of PB medication. I began to have episodes of feeling faint at the top of our stairs (but no syncope), and my HR increased only 10-12 bpm and I am fatigued.
Thursday I golt into the PM lab and they downloaded the data. The pacemaker is functioning normally, but they did increase the rate responsiveness. They could see that my heart rate had been decreasing since the problem crept up. To further diagnose the issue and tweak settings they have me taking a stress test next Thursday (June 6).
So what is happening? Has anyone else experienced this? And what was the problem? Could the lead be dislodged? BTW, the PM is not on a recall list.