SVT episode, how long is too long or when to go to ER?

An electrically disordered heart is undergoing a progression of the disorder. For some hearts it can mean several months, while for others it can take several long years for the progression to more difficult stages to manage. I don't know how long we're talking about for you, but it seems as if the bills are beginning to come due for you. You are moving along into a more advance stage.
Consult an electrophysiologist and do some serious research into catheter ablation. Unless you are willing to begin experimenting with anti-arrhythmic drugs, I do feel that you should get an ablation (if a qualified person, not me, knows it is likely to stave off further progression for a good long time).
I have had two ablations for AF. The failure rate for an index ablation to treat AF is a rather disappointing 25%, but much of that is due to both the early nature of catheter ablation, the uniqueness of each patient, and the skill and experience of the EP. Repeated ablations have a higher success rate. I don't know the stats for SVT, but I feel that they must be somewhat the same, maybe better. Again, more research for you, including finding the best EP out there near you who specializes in advanced stages of your disorder.

Thank you, @gloaming, for your thoughtful reply. I have consulted two electrophysiologists over the past year and receive ongoing care from one of them. From the initial diagnosis, I have been pressured by the EPs and other physicians to get an ablation but have been unwilling to proceed, after lots of research. (Remember, I do not have AF.) The thought of having repeat ablations for PSVT is anathema to me. Absent scientific information to the contrary, I will consider an ablation to be a life style decision, in my case.

I am happy to pass on whatever in my past may be the least bit relevant. A lot of how receptive or prescriptive an EP is going to be depends on how you say you experience your arrhythmia. Providing the burden is not high, and if you have no atrial or ventricular enlargement, or valvular degradation, you could leave well enough alone. But, if you complain that it really detracts from your sense of well-being, if you can feel a sensation that is quite objectionable, then the symptoms and their management become more important in the consideration. I was told this, as well, by my sister-in-law, now a retired oncology nurse. She said that explaining how your condition affects you, sensorily and mentally, or with other physical symptoms, is what often elicits the best care from a physician. I listened, naturally.
I hope I don't put you in an uncomfortable position, but we at afibbers.org go to great lengths to encourage patients to find the best EP money can buy, especially if they have a great track record of successful ablation and have a lot of experience with the condition presented. In some cases, you need someone who specializes in more advanced or complex cases. But, if you are comfortable with your EP, by all means go with that person. I rejected offers of referrals to other private experts when I was contemplating my own ablation because I had already met a good EP with a solid reputation. I was content with letting him try. It took him two goes, but he got 'er done the second time. 🙂

My mom has an upcoming appointment for ablation evaluation.. Her primary referred her after wearing a 2 week monitor. She has. SVT. It bothers her occasionally and she doesn’t want to take meds for it, though she is taking one now. She wants it done soon, but earliest intake appointment isn’t until mid November. Sigh.

Why not go to an electrophysiologist known for excellence and request a loop recorder to be placed under the skin in your left chest? It’s simple, painless ( they numb the skin with lidocaine) and is outpatient. Then you won’t have to wonder about what your heart rhythm has been doing. My loop recorder is from Medtronic and comes with an App that needs to stay opened at all times on your phone. A record of every heartbeat is sent to a clinic connected to your EP’s practice. They monitor everything and notify you if there is a concerning rhythm. They use this info.to determine dosages of medications.

As far as potential damage to your heart muscle’s ability to pump blood, the standard test is a simple, non-invasive echocardiogram.

Make sure to sign up on the cancellation list.

Right. I’ll do that.

RN here, long history of svt, psvt...?...managed over last few years by low dose metoprolol ER succ, 25 mg twice a day...as episodes became more frequent, and lasting longer... ablation was discussed.
I did not want to try that, as the % of success is not the greatest... MD put me on FLECAINIDE low dose. 50 mg per day...
I was leary about the warnings listed for that, but needed to make a choice... It has been a game changer for me.. I hardly ever have an episode, and if i do, it lasts less than a minute.
i have ekgs as needed, see the cardiologist every 6 months...
i know longer feel like i have a but of a handicap...
Best if luck to you, Sue

I have been debating whether to try Flecainide, which can have terrible side effects. Your message is making me think I should try Flecainide if the “rescue” med (Lopressor) is no longer doing the job, at any safe dosage. Your input has really helped, thank you Sue. Good luck to you as well.

one more thing... no one should have episodes lasting 12
hours...actually a great time to get to the office, or ER for a 12 gauge EKG......easier said than done, if you are not in a close radius of either... your risk of stroke increases with the time span of the event.
a great choice is to see an electrocardiologist, versus a cardiologist...If you can be referred, you would get much more info about your own problem... as you said, do those episodes cause increased weakening, etc?