With your left bundle branch block, low ejection fraction, and your symptoms
, you are probably a good candidate for a biventricular pacemaker
(paces left and right ventricle) and an intracardiac defibrillator. This is a single device that does both functions. I think at the minimum, I biventricular pacemaker ICD would help, but would not rule out a PVI (pulm vein isolation or ablation). It is worth thinking about once you know all the risks and benefits.
I hope this helps. Happy holidays.