Background: Cardiac catheterization is the common procedure undertaken to assess and treat coronary heart diseases. After the procedure, the patient remains on bed rest.for at least 6–24 hours in order to reduce the chance of vascular complications at the groin site. Objectives: to investigate the effect of noncompliance and compliance patients on the outcome of Diagnostic Coronary Angiography in terms of hematoma or bleeding, and pain. Methodology: It was a descriptive prospective cross-sectional hospital-based study conducted at Ahmed Gasim Cardiac Center in Sudan. Data collected among 151 Sudanese adult patients presenting for diagnostic coronary angiography, Data relevant to the study were collected by questioners and observational checklist and analyzed using (SPSS). Result: Fortunately, the majority of the participants, 76.2%, were compliant with the routine bed rest post-procedure and only 23.8% were non-compliant, the compliance of patients was not shown to have an effect on patients 94.4% up to 100% did not experience back pain.Conclusion: altering a patient's position by elevating the head of the patient's bed and side-to-side positioning was safe. This will enhance patient comfort, reduce back pain, and enable them to meet self-care needs. No difference in the incidence of vascular complications.