Remote Ischaemic Postconditioning in the Clinical Setting of NSTEACS and Urgent PCI

A Study Investigating the Cardioprotective Benefits of Remote Ischaemic Postconditioning in Patients Presenting With Non ST Elevation Acute Coronary Syndromes Undergoing In-hospital Percutaneous Coronary Intervention

This study investigates the cardioprotective effect of remote ischaemic pre-/postconditioning in patients presenting with a NSTEMI/Unstable angina undergoing PCI.

Patients presenting with Non ST elevation acute coronary syndromes (NSTEACS) - NSTEMI and Unstable angina patients are enrolled in this study. Eligible patients are approached, with patient information sheets and are consented for involvement into the study. Patients are randomised to intervention or control. Patients randomised to intervention will receive 3 x 5 minutes of forearm ischaemia (with the cuff inflated to 200 mmHg) separated by 5 minutes of reperfusion between each cuff inflation, prior coronary angiography. This protocol of episodic forearm ischaemia/reperfusion has been demonstrated to confer remote ischaemic preconditioning-induced protection. Prior to the intervention, a blood sample will be taken to measure serum troponin T and CK-MB (baseline level). Following PCI patients will be reviewed on the wards and their ongoing recovery will be assessed and reviewed prior to discharge from the study. Troponin T and CK-MB levels will be measured for the 24 hours after PCI, at various time points (6 hour, 12 hour, 24 hour) as a measure of the degree of myocardial damage, and levels compared between the different treatment groups. Primary end point Myocardial injury (Peri-procedural Myocardial Infarction and Injury) measured by cTnT and CK-MB release over 24 hours after primary PCI.

Patients will receive a standard remote ischaemia preconditioning protocol comprising a blood pressure cuff placed on arm and inflated to 200mmHg for 5 minutes and then deflated for 5 minutes, a cycle repeated three times, prior to the PCI procedure.

Patients will receive a standard sham remote ischaemia preconditioning protocol with an un-inflated cuff be placed on the arm in this group of patients for 30 minutes. This is the sham intervention for this group.

A Blood pressure cuff will be placed on the arm and inflated to 200mm hg for 5 minutes, and then deflated for 5 minutes, a cycle repeated 3 times.

Peri-Procedural Myocardial Injury will be assessed by the number of patients with peak troponin-T>3x 99th percentile upper reference limit

Inclusion Criteria: Patients admitted with NSTEMI/ Unstable angina undergoing percutaneous intervention Exclusion Criteria: Known renal failure Known liver disease Peripheral vascular disease involving upper limbs Inability to consent