Rate Response Performance and Adjustment

• by brady
• 2023-03-18 21:48:57
• Checkups & Settings
• 66 views
• 0 comments

I wish to share my experience in adjusting the rate response of my leadless dual chamber pacemakers.

The Abbott Aveir Leadless Dual Chamber Pacemakers use temperature base rate response. I could not find any publication that discusses the implementation of rate response using temperature, nor could I find any for the accelerometer base implementation.  All I could find out is the range of temperature change in the body during exercise is about 1 deg C. For the Aveir, the range of control is from 0/7 to 7/7 that is 8 increments.

In January 2023, I had my PMs for 3 months. My PMs settings were: base rate 50, max rate 120, RR 2/7. I did several experiments by walking up and down the stairs at YMCA. It took about 10 mins for the HR to rise from starting 55 to the highest 90 bpm, by then I was out of breath. So during followup, I showed the HR RR plots to the Abbott engineer and requested him to increase the RR. He agreed and changed to 5/7 and 140bpm max HR.

I then walked in the parking lot and climbed the stairs in the hospital many times; each time checked the HR rise time. I found that HR surged to max within 2-3 min. I was stressed out.  So I immediately went back to the engineer and request him to reduced the RR.  He changed to 4/7 and 120 max HR.

When I went home and did the stair climb, the rise time reduced to 5min (instead of 10) and reached 120bpm (instead of 90), the max HR. I felt good and wasn’t out of breath anymore. But there was a serious problem:  for no reason, my HR would surge to 120; when I ate, HR 120, when I urinated HR 120; ….. During each surge, I had uncomfortable palpitation. The constant surges and palpitations made my life unbearable. So I requested an urgent followup, which was granted, to have the RR back to 2/7 and 120 max HR, that were the original settings.

In summary, for this temperature based leadless pacemakers, doubling the rate response setting decreased the HR RR rise time by half and also reached a higher final HR. This made me feel better in exercise. However, faster RR caused frequent surges to max heart rate and unbearable palpitations. Cause for the surges is unknown

The tools I used was Apple Watch and the Heart Analyzer app. The former measures the heart rate every 5 seconds while the latter plots out the HR vs time. I measure my HR 24/7. This setup allows me to plot out the rate response vs time at will.