heart function following ablation

I recently had a successful AV node ablation for sick sinus syndrome which was not adequately controlled by high doses of drugs (pacemaker already in place). I no longer have to take the drugs and feel much better for this.  My remaining problem relates to physical activity.  I find that I have considerable problems with stairs or walking up even mild slopes.  The pacemaker does not seem to allow my heart rate to increase adequately, and it is irregular for a time once I stop the activity.  This has happened with the pacemaker set high (90 for the first month) or lower - it is now at 60.  The main problem is central chest pain when doing these activities, and for some time afterwards, associated with breathlessness.  My situation is somewhat complicated by the fact that I had a pneumonectomy 5 years ago (for bronchial carcinoid), and this may well be a factor, although the symptoms have become significantly worse since the ablation.  I wonder if this is a situation that is unlikely to change, or if there is any other action I can take? I would be interested to know also if you have encountered patients with similar problems with long-term arrhythmias following pneumonectomy - my cardiologist thinks that there is no connection, but the electrophysiologist thinks there is.
Thank you.

[CCF-M.D.-CRC]

Dear irene,

It may be possible to adjust your pacemaker to give you a faster heart rate sooner when you start to exercise.  The feature on the pacemaker that does this is called "rate-response".  There are different sensitivity settings for this feature.  Therefore if the sensitivity is increased then the heart rate will go up will less activity. I would ask about the possibility of changing the rate-response at your next visit.  

I personally haven't had any patients with arrhythmias after pneumonectomy but I suppose it is possible there is a link.  Any other readers of the forum notice this connection?

[beachjay]

I had a lung resection in 1995 for a carcinoid tumor. Two years ago developed severe arrhythmia.I hadn't thought of any connection.