What LVEF % justifies 2 wire or 3 wire? What determend if Med's working or not?
Your doctor chooses which type of pacemaker to implant, based on many variables. LVEF doesn't tell the whole story. Why is the LVEF low and will CRT help? If the reason is electrical, LBB for example, it probably will. If the problem is structural (eg damage from a heart attack) maybe not. In any case, the decision isn't your responsibility. Relax.
The meds question is pretty open ended. The meds are working if you're getting and feeling better. Sometimes you know they're working because you're still alive.
Your LV EF% tells us and you nothing about the *cause* of reduced LV function. You can see significantly reduced EF with lack of AV synchrony as reduced ventricular filling will reduce EF. Or from a cardiomyopathy which is a lot less fun.
What matters is the underlying cause - disease process - and what's available to improve things. In general (warning, sweeping generalisation follows), ventricular pacing alone doesn't seem to be the optimum and RV alone seems to be even worse for some patients. This is the basis of cardiac resynchronisation therapy for heart failure where the LV is specifically activated separately from the RV. And for some folk with reduced or no AV node function some therapies are impossible. Some patients do better on a given drug than others. There is a huge range of biological difference even within a diagnostic group - we're only at the beginning of understanding just how much of our genetic inheritance impacts our lives and diseases.
There are major conferences, trials etc about 'the best' treatment for each diagnostic sub-group with some big differences between countries.
All you can do is have a good, clear talk with your EP doc, discuss the available *evidence* about what's best for patients with your condition and then make a shared decision. Details - important details - about brand of PM, model of PM box, sensors, should also come into that discussion, but it's secondary to getting you to the best possible heart health and keeping you there for as long as possible while you get on with living your life. Please don't end up sweating over changes in EF - how you feel whilst living your life is the most important. It's still a useful number, but it's only a convenient marker of how well your heart muscle is performing and there's quite a lot of measurement variability involved - but a low EF is worrying and a normal EF is nicer.
What determines the type device you get, or even whether you get one is the most expensive device your insurance agrees to pay for.
Many benefits of medicines are hidden. For example, Beta Blockers help reduce the work load on your heart. You aren't going to feel anything but your heart is under less strain and can heal to,some as fastdegree, or at least not devolve
You know you're wired when...
You have a shocking personality.
Hang in there; it does get better every day!