At least 40 U.S. veterans died waiting for appointments at the Phoenix Veterans Affairs Health Care system, many of whom were placed on a secret waiting list.

The secret list was part of an elaborate scheme designed by Veterans Affairs managers in Phoenix who were trying to hide that 1,400 to 1,600 sick veterans were forced to wait months to see a doctor, according to a recently retired top VA doctor and several high-level sources.

Internal e-mails obtained by CNN show that top management at the VA hospital in Arizona knew about the practice and even defended it.

When a veteran comes in seeking an appointment, "they enter information into the computer and do a screen capture hard copy printout. They then do not save what was put into the computer so there's no record that you were ever here,"

The information was gathered on the secret electronic list and then the information that would show when veterans first began waiting for an appointment was actually destroyed.

"That hard copy, if you will, that has the patient demographic information is then taken and placed onto a secret electronic waiting list, and then the data that is on that paper is shredded."

"So the only record that you have ever been there requesting care was on that secret list," he said. "And they wouldn't take you off that secret list until you had an appointment time that was less than 14 days so it would give the appearance that they were improving greatly the waiting times, when in fact they were not."