Slow recruitment

The current study is an amendment to a previously approved blinded randomized controlled trial (NCT02697812) which examines the rate at which the sternal retraction maneuver is performed during cardiac surgery (standard over 30 seconds versus. gradual over 15 minutes) and examines the incidence of chronic post-sternotomy pain 6 months following surgery.

Patients enrolled in the parent study will be identified at the 6 month follow-up and recruited in terms of whether they report chest pain. A total of 30 participants will be recruited (15 with and 15 with no pain) to undergo a single MRI session in which functional MRI will be done on the brain stem and spinal cord and anatomical MRI images will be collected for specific chest and neck structures. This will indicate whether there are long-term differences in pain processing and/or physical damage to neck and chest structures in those with and without chronic pain 6 months following coronary artery bypass graft surgery. All functional and anatomical MRI images will be reviewed and interpreted with study personnel blinded to whether the patient is reporting pain or no pain at their 6 month follow-up interview.

Inclusion Criteria:

• Elective Primary Coronary Artery Bypass Surgery
• Understanding and provision of written informed consent
• Age > 18 and < 75
• ASA class I, II or II

Exclusion Criteria:

Any combined or redo cardiac procedure

• Current alcohol or substance abuse
• Pre-existing chronic pain requiring chronic analgesic use
• Rest pain in proposed surgical area at baseline, preoperatively
• Chronic Steroid use
• Inability to perform post-operative assessments

The study population will be those enrolled in a parent blinded randomized controlled trial (NCT02697812). At their 6 month post-cardiac surgery interview, patients reporting no chest pain (n=15) or chest pain (n=15) will be recruited to undergo an MRI.