0057: Ischemic postconditioning reduces infarct size: systematic review and meta-analysis of randomized controlled trials

Abstract

To provide an updated synthesis on the efficacy of IPost on accurate surrogate markers of IS. Infarct size (IS) is a major determinant of patient outcome after acute ST-segment elevation myocardial infarction (STEMI). Interventions aiming at reducing reperfusion injury such as cardiac ischemic postconditioning (IPost) may reduce IS and improve clinical outcomes. IPost, was shown to be feasible in patients with STEMI treated by primary percutaneous coronary intervention (PPCI). We performed a meta-analysis of randomized controlled trials that evaluated the efficacy of IPost in STEMI patients undergoing PPCI. Main outcome was the area under the curve (AUC) of serum CK release (CK-AUC). Secondary outcomes were other surrogate biomarkers of IS, complete ST-segment resolution (cSTR), direct measure of IS by single-photon emission computed tomography (SPECT) or estimate of the IS by cardiac magnetic resonance (CMR). Eleven studies were selected including 1313 STEMI patients undergoing PPCI with or without IPost. Compared to control, we observed a significant reduction of CK-AUC (SMD –2.84, 95%CI-5.43 to –0.25 IU/L, p=0.03). Other surrogate markers like CMR (SMD –0.36, 95%CI [–0.88, 0.15], p=0.16) showed a non-significant IS reduction in the IPost group. This meta-analysis dealing with accurate surrogates of IS such as CK-AUC suggests that IPost reduces IS. These results should be interpreted cautiously because of limited samples sizes. Whether this translates into cardiac function and patient’s prognosis improvement still needs to be demonstrated in larger prospective sufficiently powered randomized controlled studies. Abstract 0057 – Figure: Forest plots of biologic surrogates of infarct size