Heart Failure Support Group
Heart failure is a condition that can result from any structural or functional cardiac disorder that impairs the ability of the heart to fill with or pump a sufficient amount of blood throughout the body. It is often undiagnosed due to a lack of a universally agreed definition and difficulties in diagnosis, particularly when the condition is considered "mild."
I'd be more concerned about the number of issues that have arisen. You might want to consult an independent Electrophisiologist to get another opinion. This is a very common procedure (implant) and it sounds like amateur hour. Granted this does happen but is rare.
And while I think your 5 % number is a bit low, cardiac resynchronization devices are implanted far too often and do not benefit the patient. The number one this she should have to justify a CRT (3 lead device) is LBBB (Left bundle branch block. The device is used to force the ventricles to beat simultaneously improving the heart output (ejection fraction EF).
Good luck
Good luck