The Southern Health Trust has set up a helpline to deal with concerns raised over outpatient appointments.
It follows claims by a senior consultant who works at the Craigavon Area Hospital.
He said patient safety was being put at risk because of a concentration on meeting targets.
Trust chief executive, Mairead McAlinden, has rejected this and said there was "no evidence" any patient had come to harm.
She met the health minister, Michael McGimpsey, on Thursday afternoon.
Afterwards, she said the trust had set up the information line because of "media coverage" on the appointments issue.
"It will be open from 1700 GMT this evening and we will be able to take calls from any patient who has a concern in relation to their outpatient review appointments," she added.
The trust said it was working on a solution for an increased demand for outpatient reviews.
Earlier, the consultant, who did not want to be identified, said post-operative patients had their case reviews postponed as doctors are too busy trying to meet new patient targets.
Hospitals have to meet targets for new patients but not for outpatients.
In response, Ms McAlinden said the trust would "cancel appointments for a number of reasons" and could not give an "absolute categorical assurance that on one occasion that did not happen".
But she said she was giving "an assurance today" the trust was "prioritising patients on the basis of their clinical priority and their condition".
The consultant also claimed patients that were being brought back for a review appointment were prioritised by the alphabetical order of their surname in order to meet the new patient targets. The trust has denied this claim.
One patient, Eric Quigley, told the BBC on Thursday that he had waited nine years for a review appointment after suffering major heart problems.
Ms McAlinden asked the Quigley family to contact her so she could investigate and explained the process for review appointments.
"The system works in three levels, anyone who requires a review within six weeks will be seen first," she added..
"Patients who are on special drug treatments and are required to be seen within a particular time frame are allowed review appointments next.
"The remaining non-urgent or routine patients are selected for booking in date order."
Ms McAlinden also expressed "disappointment" that staff at Craigavon were coming to the media with allegations instead of raising them with managers in the trust.
"I would once again ask that this colleague - or colleagues - making public allegations would come forward in complete confidence to either myself, our medical director, or any of our senior consultant medical team and we will make ourselves immediately available to discuss the details of their concerns."
She said she had reassured Mr McGimpsey that it was "properly managing" patients on the basis of "clinical priority and the urgency of their condition".
The number for the information helpline is 02838 614166. It will be open from 0800 GMT to 2000 GMT for an "interim period".