Aim of the study:
The study aims at a preliminary assessment of the occurrence of PTSD among patients awaiting major heart surgery and the assessment off the reliability of the Impact of Event Scale – Revised (IES-R).

Subject or material and methods:
100 consecutive patients scheduled to non-emergency cardiac surgery were screened using a brief list of PTSD symptoms. Those who responded affirmatively, were ask to fill in the IES-R and then underwent structured Mini International Neuropsychiatric Interview (MINI) and a clinical assessment according to the DSM-5 criteria.

Results:
Fourteen of fifteen patients who completed the IES-R obtained results indicating a possibility of PTSD. Five of them refused to undergo a psychiatric examination. Four of nine patients whose IES-R scores indicated PTSD, met its criteria according to MINI. and DSM-5. One PTSD case was related to cardiological problems.

Discussion:
The results of the present study do not support the hypothesis that heart disease is a stressor causing PTSD in patients awaiting cardiac surgery. Moreover, the results impair the conclusions suggesting high rate of PTSD occurrence among some populations of cardiological patients, in research conducted with self-rating scales. The results of the presented study demonstrate that clinical psychiatric examination is necessary to properly confirm a PTSD diagnosis.

Conclusions:
The prevalence of PTSD (4%) in the study group was higher than in the general population in Poland, but the heart related stressor was found only in one case (1%), that is equal with the rate of PTSD. The reliability of IES-R is low due to a large number of false-positives.