Background: Cardiac pain arising from acute coronary syndrome (ACS) is a multi-factorial phenomenon. Historically, episodes of cardiac pain have been captured using a one-dimensional numeric pain rating scale. Lacking in clinical practice are acute pain assessments that employ a comprehensive evaluation of an emergent ACS episode. Aim: To examine the sensory-discriminative, motivational-affective and cognitive-evaluative dimensions of ACS-related pain. Methods: A descriptive-correlational, repeated-measure design was used to collect data on 121 ACS patients of their cardiac pain intensity. The (numeric rating scale-NRS 0-10 scale) measured chest pain "Now" and "Worst pain in the previous 2 hours over 8 hours" and the McGill Pain Questionnaire Short-Form (MPQ-SF) measured pain at 4 hours. Results: Mean age was 67.6 ± 13, 50% were male, 60% had unstable angina and 40% had Non-ST-elevation myocardial infarction. Cardiac pain intensity scores remained in the mild range from 1.1 ± 2.2 to 2.4 ± 2.7. MPQ-SF: 66% described pain as distressing and 26% reported pain was horrible or excruciating. Participants described ACS pain quality as acute injury (nociceptive pain: heavy, cramping, stabbing), as nerve damage (neuropathic: gnawing, hot-burning, shooting) and as a mixture of acute and chronic pain qualities (aching, tender and throbbing).