Impact of Remote Ischemic Preconditioning Preceding Coronary Artery Bypass Grafting on Inducing nEuroprotection

Summary

Coronary artery disease (CAD) is the leading cause of death worldwide. Patients with severe CAD are often treated with coronary artery bypass grafting (CABG). Novel treatment strategies need to be pursued to respond to the continuous increase in the risk profile of contemporary CABG patients. Surgical myocardial revascularization is commonly performed with the use of cardiopulmonary bypass (CPB). Neurological impairment following CABG may take on the form of a new-onset motor deficit or postoperative cognitive dysfunction. The former is rare, but potentially devastating. Conversely, declines in attention, memory and fine motor skills can frequently be documented.

Ischemic preconditioning is a phenomenon of an endogenous protective response to organ ischemia, which is triggered by brief cycles of nonlethal ischemia and reperfusion in tissues known to be more resistant to ischemic insults. In clinical practice remote ischemic preconditioning (RIPC) is achieved by inflicting short periods of ischemia with intermittent restitution of flow to the upper extremity. This intervention has been shown to be effective in the reduction of myocardial injury in cardiac surgical patients. The hypothesis tested in this research proposal is that RIPC will decrease the extent of postoperative neurological injury following CABG.

In this research project, 70 patients scheduled for an elective CABG will be recruited at a single center. They will be randomly allocated to either undergo RIPC (intervention arm) or a sham procedure (control arm). Inflating a blood pressure cuff to 200 mmHg for 5 min will induce RIPC, thereby inducing a brief period of ischemia. This will be followed by a 5-minute arm reperfusion. In total, three cycles of arm ischemia and reperfusion will be induced in this fashion.

All patients will undergo pre- and post-procedural magnetic resonance imaging (MRI) of the brain, as well as neurocognitive testing. The array of MRI tools that will be used for the quantification of brain injury will include fluid attenuated inversion recovery, diffusion weighted and susceptibility weighted imaging, coupled with resting state functional MRI.

The investigators aim to determine whether RIPC can reduce the adverse impact of CPB on neurological outcome as evaluated by MRI detectable brain ischemia and neurocognition.

Conditions

• Brain Ischemia
• Postoperative Confusion

Interventions

PROCEDURE

Remote ischemic preconditioning

A blood pressure cuff will be placed on the left arm and three cycles of 5 min ischemia followed by 5 min reperfusion will be applied.

PROCEDURE

Control

The cuff will be placed around the arm but not inflated.

Sponsors & Collaborators

• Clinical Hospital Centre Zagreb

  collaborator OTHER

• University of Zagreb

  lead OTHER

Principal Investigators

• Hrvoje Gašparović, MD, PhD · University of Zagreb School of Medicine

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

TRIPLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2014-03-31

Primary Completion

2015-10-31

Completion

2016-03-31

Countries

• Croatia

Study Locations