Hi muchostinky - do you know why they have said you would probably have to have an epidural? It could be because epidurals lower blood pressure, which can be a good thing depending on the nature of your heart condition. But they can also slow down labour, and tend to make the pushing stage harded - which is not necessarily a good thing if you don't want to be pushing for too long or too forcefully. If you do have an epidural, it might be worth asking if they will allow passive descent, that is basically avoiding any pushing at all until the baby is almost crowning. It can take a little longer but it takes a lot of stress off you and the baby.
In terms of the baby currently being in a breech position, the first thing is that you are 35 weeks - could still be 5-7 weeks to go, so there is still time for your baby to turn. You could also consider some of the "natural" ways to encourage him or her to turn such as acupuncture, moxibustion or hypnosis. Chiropractors with experience of something called the Webster Technique might also be able to help. There are loads of ideas on the net if you google it.
But if you get to 37 weeks and baby has not turned, you do have the option of the ECV. As another poster said they should do this in combination with ultrasound to see what position baby is in - bottoms and heads can feel very similar at this stage! Yes ECV can be uncomfortable, but they shouldn't be really painful, and they may be able to offer you some gas and air during it. Yes it's true that sometimes they don't work, although sometimes they can work on a second try if not on the first. Of course if it works then all well and good!
The main thing really at this stage is to think about what you really want. I can completely understand you feeling stressed and hormonal but is opting for a section just to get your own back on an unpleasant Dr. really a good idea?! Bear in mind things like the recovery period afterwards, impact on your future fertility, plus increased risk of problems such as placenta previa with future pregnancies, as well as the impact on the baby - in general vaginal births are safer for babies than elective cesareans. Of course with a breech baby there are more risks with vaginal births, but these still have to be weighed up against the risk of a cesarean.
Bear in mind too that if you have the ECV and baby does not turn, you might have the option of allowing yourself to go into labour naturally before having the cesarean. This might be worth asking your Dr. about. This would give your baby the benefits of the hormones your body will create when labour begins, which means they are less likely to have breathing difficulties etc when they are born (a common problem with elective cesareans).
The other thing is - would you and/or your doctor consider a vaginal birth even if the baby does not turn or is that completely out of the question? Remember that you can always opt for a cesarean at any stage if things look dicey (and if you do have the epidural, can be whipped straight into theatre).
Can you sit down with a piece of paper and write down all the pros and cons of each course of action i.e elective section, ECV, etc. ? Sometimes this can help to make things clearer.
Good luck with whatever you decide - only you know what is right or wrong for you and your baby.