Apparently it was a good idea in theory, but had few takers.
The AMA CPT agenda for February 2017 is out, and Agenda Tab 13 is:
[details after the break]
Delete Code 46762
Sphincteroplasty, adult, implantation of artificial sphincter.
The code was only used 10-15 times per year in recent years, in Medicare data (about once per each 4M beneficiaries). 60% of procedures were hospital outpatient, 40% hospital inpatient, and the Medicare surgeon's fee was $946.74.
Despite the low utilization, there is a trickle of publications in this field, e.g. here and here.
Fecal incontinence is a serious and not uncommon issue, but as a solution, implantation of artificial sphincter did not seem to have much adoption.
There may have been more demand in 2017.