Arrhythmia and Zytiga

[bean1008]

I have been on abiraterone for about a year and a half along with Lupron. I’m currently seeing a cardiologist because the last two weeks I’ve developed heart palpitations/arrhythmia. Of course it’s always hard to pin the blame but I wonder if anybody else had heart issues when they were taking abiraterone? I just finished a week of a heart monitor looking for an answer and this is all making me a bit anxious! I’m wondering if I should request to my MO to end the drug and just stay on Lupron or try something different. And if I did end the abiraterone, will my heart return to normal (assuming that’s the cause)? So many questions…Just wondering if anyone out there went through something similar.

Thanks!

[Tall_Allen]

ADT can cause in arrhythmias:

academic.oup.com/jes/articl...

In this study, Zytiga didn't:

ncbi.nlm.nih.gov/pmc/articl...

Perhaps switching to Firmagon (or Orgovyx or orchiectomy) may help:

pubmed.ncbi.nlm.nih.gov/286...

[tango65]

Zytiga will cause arrhythmias if there is very low potassium (hypokalemia). If your K is normal, then the arrhythmia have other cause.

[Carlosbach in reply to tango65]

Yeah, my potassium levels dropped dramatically on ADT. Even though my heart has always been strong, my Dr. cautioned me about arrhythmia while I was working to stabilize my potassium.

[tango65 in reply to Carlosbach]

They may need to increase the dose of prednisone or add inspra to try to stabilize the K.

[bean1008]

Good questions… I have not had any blood work to check for things like magnesium, potassium… I even read about possible anemia or thyroid issues can cause this. The plan is to go in next week for a follow up to the monitor and then hopefully we can get some answers! Sure is frustrating.

[bean1008]

Thank you all for your comments! The cardiologist thinks possibly nothing to worry about but I don’t know if he understands the potential issues with the ADT drugs. I feel like my oncologist needs to talk to the cardiologist or vice a versa and hopefully I can make that happen. Another instance of having to be our own best advocate!

[bean1008]

Thanks so much, Nakakrats!

[middlejoel]

Hi,In December 2019, I became resistant as Lupron failed and PSA continued to rise. I was put on Provenge and Zytiga and due to good results went on a holiday in June 2020. Psa returned in early 2021 and I did a 5-day SBRT. It was around 2019-20 about the time that I was put on Provenge and Zytiga that I developed A-Fib and continued until a few months

past the date when I stopped Zytiga. Was the heart issues caused by Zytiga or was it a coincidence?

[bean1008 in reply to middlejoel]

That’s where I am at as well… makes you wonder! But in talking to my sister yesterday I discovered that she has an arrhythmia as well so maybe it is genetic?

[ck42]

Started Zytiga, ( along with Lupron from beginning ), 6/2019, developed persistent A Fib 11/2021. Oncologist thinks it might be Zytiga so I dropped it 3/15/22 as test. So far, still in A Fib; thankfully PSA still undetect 4/17. Next blood test 5/17 - will decide future then. Did try electro cadioversion 2/22 - unsuccessful. Thinking about Orgovyx in place of Lupron but no convincing guidance yet. Cardiac guy wants to do catheter ablation but I want to wait a while.

[bean1008 in reply to ck42]

Ck42 it sounds like we are in a similar spot. I got my diagnosis last night for left ventricular hypertrophy. I’ve been on the abiraterone for close to 15 months now… I wrote to my oncologist this morning to ask about discontinuing it as I believe it’s a contributing factor in the heart issue. I had an ultrasound treadmill test only last August and I’d checked out fine. The only change in my life since has been the addition of the Lupron and Zytiga. I read about a new field called cardio oncology… I asked if I should transfer care from my current cardiologist. Maybe we should both be on Regulix instead? Keep me posted!

[timotur]

I had occasional palpitations related to caffeine intake before PCa dx, but when I was on Zytiga, I had a couple of events that scared me-- one palpitation episode lasted about 15-20 minutes and I couldn't stop it as I usually could by drinking water and laying down for a few minutes. Zytiga was also causing high BP from 115/75 to 165/98, so I dropped it after six months and continued on Lupron for another year.

[bean1008 in reply to timotur]

I know my oncology team does not want me to drop the zytiga. I’m wondering if I should just stick to the Lupron like you. Thanks Timotur!

[timotur in reply to bean1008]

I did about six months of Zytiga and 18 months of Lupron-- used both two months before heading into Brachy/IMRT radiation treatment, where I think I got the most bang for the buck-- sensitizing the PCa to radiation and weakening or killing any hormone-sensitive PCa cells. Reading your bio, it appears you may be headed to salvage radiation as a next step after RP & resection, and with Gleason 9, I would try to stay on Zytiga, at least until you have salvage radiation. Perhaps, discuss with your MO a reduced dose of Zytiga, 3/4 or 1/2 dose, leading up to your next treatment, and then re-evaluate. Definitely, have a cardiologist do an EKG, and ask him to comment on whether you have "lengthening of the QT interval", which is associated with ADT, which may contribute to arrhythmias. Just MO-- Tim

[bean1008 in reply to timotur]

Thanks Tim! Cardiologist does not seem too concerned and neither does my oncologist so I will try and stick with the status quo. I’ve been reading interesting things about adding the radiation at the end of the ADT so it sounds like you are on a good path! I was in a clinical trial for a new type of radiation called neutron radiation and I will be looking into that as an option… I was in the control group during the study (only drug therapy) but was told that if I wanted to try the radiation in the future I was welcome. Supposedly it’s a very intense beam but it’s extremely narrow in focus. It’s been used successfully and throat cancer and the lead radiologist was very hopeful about it having success with prostate cancer. I need to follow up with them and see how the study is going! Best wishes to you!

[timotur in reply to bean1008]

Ok great, good news on your QT interval, which means that is not adding to the problem. One other tip on arrhythmias you probably already know is to stay hydrated and drink electrolytes, especially after exercising. I had my worst palpitation once after running in hot weather, which started reoccurred every two hours, until I went to the ER to get an IV to replace fluids.

On salvage radiation, I would guess that it would be similar to my IMRT that followed Brachy-- which was 25 sessions of 1.8gy . For this, you would want a large coverage area rather than a narrow beam I believe. Best to you..! -- Tim

[bean1008]

P.s. my qt interval was 381 so right in the normal range.