Insertion, replacement or removal of implantable defibrillator generator, if the patient has one of the following: (a) a history of haemodynamically significant ventricular arrhythmias in the presence of structural heart disease; (b) documented high-risk genetic cardiac disease; (c) ischaemic heart disease, with a left ventricular ejection fraction of less than 30% at least one month after experiencing a myocardial infarction and while on optimised medical therapy; (d) chronic heart failure, classified as New York Heart Association class II or III, with a left ventricular ejection fraction of less than 35% (despite optimised medical therapy); other than a service to which item 38212 applies (H) (Anaes.) (Assist.)