Remote Ischaemic preconditioning reduces myocardial injury in patients undergoing cardiac surgery with cold blood cardioplegia:a randomised controlled trial.

Heart. 2009 Jun 8; Venugopal V, Hausenloy DJ, Ludman A, Di Salvo C, Kolvekar S, Yap J, Lawrence D, Bognolo G, Yellon DMOBJECTIVE: Remote ischaemic preconditioning (RIPC) induced by brief limb ischaemia reduces myocardial injury in coronary artery bypass (CABG) surgery patients receiving predominantly cross-clamp fibrillation for myocardial protection. However, cold-blood cardioplegia is the more commonly used method worldwide. This study was designed to assess whether RIPC is cardioprotective in CABG patients receiving cold-blood cardioplegia. DESIGN: Single centre, single-blinded, randomised controlled trial. SETTING: Tertiary referral hospital in London. PATIENTS: Adults patients (18-80 years) undergoing elective CABG surgery with or without concomitant aortic valve surgery with cold-blood cardioplegia. Patients with diabetes, renal failure (serum creatinine >130 mmol/L), hepatic or pulmonary disease, unstable angina or myocardial infarction within the last 4 weeks were excluded. INTERVENTIONS: Patients were randomised to receive either RIPC (n=23) or control (n=22) following anaesthesia. RIPC comprised three 5-min cycles of right forearm ischaemia, induced by inflating a blood pressure cuff on the upper arm to 200mmHg, with an intervening 5 min reperfusion. The control group had a deflated cuff placed on the upper arm for 30min. MAIN OUTCOME MEASURES: Serum troponin-T was measured pre-operatively and at 6, 12, 24, 48 and 72 hours post-surgery and the area under the curve (AUC72hrs) calculated. RESULTS: RIPC reduced absolute serum troponin-T release by 42.4% (AUC72hours 31.53+/-24.04 microg/L.72hrs in RIPC vs 18.16+/-6.67microg/L.72hrs in control; 95% CI 2.4-24.3; p=0.019). CONCLUSIONS: Remote ischaemic preconditioning induced by brief ischaemia of the arm reduces myocardial injury in CABG patients receiving cold-blood cardioplegia making this non-invasive cardioprotective technique widely applicable clinically.