Bradycardic from PVC's overriding ICD

[Brnvc]

I have a Medtronic Virtuoso set at 60 bpm but have recently started suffering from frequent PVC's that give me a bp monitor heart rate of 45-50 and I feel awful. I had open heart surgery in May of 2007 -- a full maze procedure (cutting and cryo), an MV repair and LAA resection. It was very successful. Now my drs tell me my heart is being paced at 60 but because of the PVC's I can't feel it and it doesn't register on my monitor. In fact, it FEELS like 45 bpm and I have no stamina. For years I suffered from severe MVP, HCM, had V-Tachs, and finally developed Afib. MY EF was always somewhat normal.

My first ICD was put in in 2003 and, with Amiodarone, produced three years of great results until the Amiodarone attacked my thyroid (AIT) in 2005 and the Afib went out of control.

Prior to the surgery, I had frequent Afib and had to be cardioverted because my heart couldn't tolerate it and I wouldn't self-convert. After the surgery, I continued on Atenolol and a small amount of Lisinopril to keep me out of Aflutter, but am virtually Afib-free. In general, the surgery was successful... only suddenly the PVC's have become very frequent, persistent and are causing much discomfort, tiredness, etc. I have an elongated Q curve so most anti-arrhythmic drugs are contraindicated and I can no longer take the Amiodarone.

Are these PVC's (as many as 360 an hour in tri- and bi-geminals) dangerous and are they effecting my EF? Is there a medication, herbal supplement, or another procedure I should undergo?

I feel worse than I did before I had the ICD in 2003 which made me feel normal -- because my heart rate stayed at 60 bpm or above! My doctors are dismissive of my distress now. We're both worn out and I'm feeling pretty hopeless of late. I've been through a lot and feel like I'm becoming an invalid again.

Thanks for any advice you can give me. - Julia

[Michael J. McWilliams, M.D.]

Are these PVC's (as many as 360 an hour in tri- and bi-geminals) dangerous and are they effecting my EF? Is there a medication, herbal supplement, or another procedure I should undergo?

That is tough situation.  If I saw a patient in clinic with a similar situation, I would try the following.  I do not think there is good data to have an evidenced based plan, but this is what I would consider.

1. I would increase the base rate of your ICD first to 70 and then to 80 to see I could overdrive the PVCs.
2. I would re evaluate the amiodarone issue.  some thyroid issues can be managed with amiodarone.  If it causes hyperthyroidism, I would consider radio ablating the thyroid and restarting the amio.  If it causes hypo thyroidism, I would consider simply treating  you with amio and synthroid.
I would only do these measure if your quality of life was significantly affected by the PVCs.

There is not a herbal that is known to help.

If the PVC is of a single morphology (shape), it might be possible to ablate it.  I would exhaust all medication options for I considered this.

I hope this helps Julia, thanks for posting.

[Brnvc]

Thank you, Michael. This is a terrible predicament as I've been studying it. I see that drugs to suppress the symptoms are dangerous and I agree with that. The AIT caused a fluctuation between hypo and hyper thyroidism so it would have to be ablated or removed. After that, my lungs will be at risk. Do you know if Dronedarone is available anywhere in the world? I would travel to obtain it. Increasing the base rate is a fascinating possibility.

I feel that my arrhythmia has simply morphed into another form. It's like the electrical demon will out one way or another. I am cured of the afib, had one severe episode of aflutter, and now this. Maybe it too will pass. I do not know about the morphology but each peak looks similar on the strip. The EP lab at MGH is very bad but my Calif EP is David S. Cannom so I will probably have him treat it -- or go to Cleveland. At least with Dr. Cannom I will be less fearful.

Again, thank you.