Update on Rate Response

• by Pollyanna
• 2010-06-18 12:06:55
• Conditions, Meds & Tests
• 1511 views
• 1 comments

Hello to all,
My visit to the pacemaker clinic this morning was a huge success. This was a follow up to a treadmill test last week which revealed that although my pacemaker was working well and pacing the ventricle 100% of the time the atrium was not working well and was not able to keep up with the demands of exercise. The ECG showed that while I was on the treadmill my heart rate rose to 113bpm and then suddenly dropped to 60bpm (my lower limit). I managed 4 minutes on the treadmill and collapsed.
Lots of adjustments were made and this morning the treadmill test was repeated. I managed 15 minutes on the treadmill and although I felt exhausted I didn’t collapse like last week. I also recovered very quickly once I stopped. I feel so much better already!
The pacemaker technician has been very helpful and was happy to answer my questions. I am now much clearer about how my heart is functioning and about how the pacemaker is helping. He explained that as my pacemaker was implanted for complete heart block the rate response had been on at a very low setting as it was thought that I wouldn’t need it. The atrium had appeared to be working as it should. At my six month check the ventricle was pacing 100% while the atrium was only pacing at about 5% as the pacemaker only paced it when the rate went below 60bpm. The pacemaker was not able to tell that the atrium was not functioning well as its job was simply to pass on the atrial pulse to the ventricles. This meant that any physical activity was very difficult and I was often short of breath and lightheaded. Today the rate response has been turned up to very high and is now able to sense that the atrium is not responding properly when I am exercising and so the pacemaker takes over and paces the atrium. I feel really good at the moment and will be taking the dogs for a long walk on the fen later, who knows I might even jog the seven miles around the fen!!!!
I hope my explanation is understandable and that it might be useful to others experiencing the same problems. It looks as though the rate response is not needed for heart block unless the heart block is accompanied by problems with the atrium and that this particular problem (not quite sure what that is) does not show up on a resting ECG but it does show up on an ECG while exercising on a treadmill.
I would welcome any comments on this and any corrections if you think I have misunderstood. There is so much to take in and I am easily confused!
Best wishes to all
Pollyanna