The RIPOST-MI study, assessing remote ischemic perconditioning alone or in combination with local ischemic postconditioning in ST-segment elevation myocardial infarction.

Local ischemic postconditioning (IPost) and remote ischemic perconditioning (RIPer) are promising cardioprotective therapies in ST-elevation myocardial infarction (STEMI). We aimed: (1) to investigate whether RIPer initiated at the catheterization laboratory would reduce infarct size, as measured using serum creatine kinase-MB isoenzyme (CK-MB) release as a surrogate marker; (2) to assess if the combination of RIPer and IPost would provide an additional reduction. Patients (n = 151) were randomly allocated to one of the following groups: (1) control group, percutaneous transluminal coronary angioplasty (PTCA) alone; (2) RIPer group, PTCA combined with RIPer, consisting of three cycles of 5-min inflation and 5-min deflation of an upper-arm blood-pressure cuff initiated before reperfusion; (3) RIPer+IPost group, PTCA combined with RIPer and IPost, consisting of four cycles of 1-min inflation and 1-min deflation of the angioplasty balloon. The CK-MB area under the curve (AUC) over 72 h was reduced in RIPer, and RIPer+IPost groups, by 31 and 29 %, respectively, compared to the Control group; however, CK-MB AUC differences between the three groups were not statistically significant (p = 0.06). Peak CK-MB, CK-MB AUC to area at risk (AAR) ratio, and peak CK-MB level to AAR ratio were all significantly reduced in the RIPer and RIPer+IPost groups, compared to the Control group. On the contrary, none of these parameters was significantly different between RIPer+IPost and RIPer groups. To conclude, starting RIPer therapy immediately prior to revascularization was shown to reduce infarct size in STEMI patients, yet combining this therapy with an IPost strategy did not lead to further decrease in infarct size.

Microparticle release in remote ischemic conditioning mechanism.

Remote ischemic conditioning (RCond) induced by short periods of ischemia and reperfusion of an organ or tissue before myocardial reperfusion is an attractive strategy of cardioprotection in the context of acute myocardial infarction. Nonetheless, its mechanism remains unknown. A humoral factor appears to be involved, although its identity is currently unknown. We hypothesized that the circulating microparticles (MPs) are the link between the remote tissue and the heart. MPs from rats and healthy humans undergoing RCond were characterized. In rats, RCond was induced by 10 min of limb ischemia. In humans, RCond was induced by three cycles of 5-min inflation and 5-min deflation of a blood-pressure cuff. In the second part of the study, rats underwent 40 min myocardial ischemia followed by 2 h reperfusion. Infarct size was measured and compared among three groups of rats: 1) myocardial infarction alone (MI) (n = 6); 2) MI + RCond started 20 min after coronary ligation (n = 6); and 3) MI + injection of RCond-derived rat MPs (MI + MPs) (n = 5). MPs from endothelial cells (CD54(+) and CD146(+) for rats and humans, respectively) and procoagulant MPs (Annexin V(+)) markedly increased after RCond, both in rats and humans. RCond reduced infarct size (24.4 ± 5.9% in MI + RCond vs. 54.6 ± 4.7% in MI alone; P < 0.01). Infarct size did not decrease in MI + MPs compared with MI alone (50.2 ± 6.4% vs. 54.6 ± 4.7%, not significantly different). RCond increased endothelium-derived and procoagulant MPs in both rats and humans. However, MP release did not appear to be a biological vector of RCond in our model.

RISK and SAFE signaling pathway interactions in remote limb ischemic perconditioning in combination with local ischemic postconditioning.

Local ischemic postconditioning (IPost) and remote ischemic perconditioning (RIPer) are promising methods to decrease ischemia-reperfusion (I/R) injury. We tested whether the use of the two procedures in combination led to an improvement in cardioprotection through a higher activation of survival signaling pathways. Rats exposed to myocardial I/R were allocated to one of the following four groups: Control, no intervention at myocardial reperfusion; IPost, three cycles of 10-s coronary artery occlusion followed by 10-s reperfusion applied at the onset of myocardial reperfusion; RIPer, 10-min limb ischemia followed by 10-min reperfusion initiated 20 min after coronary artery occlusion; IPost+RIPer, IPost and RIPer in combination. Infarct size was significantly reduced in both IPost and RIPer (34.25 ± 3.36 and 24.69 ± 6.02%, respectively) groups compared to Control (54.93 ± 6.46%, both p < 0.05). IPost+RIPer (infarct size = 18.04 ± 4.86%) was significantly more cardioprotective than IPost alone (p < 0.05). RISK pathway (Akt, ERK1/2, and GSK-3ß) activation was enhanced in IPost, RIPer, and IPost+RIPer groups compared to Control. IPost+RIPer did not enhance RISK pathway activation as compared to IPost alone, but instead increased phospho-STAT-3 levels, highlighting the crucial role of the SAFE pathway. In IPost+RIPer, a SAFE inhibitor (AG490) abolished cardioprotection and blocked both Akt and GSK-3ß phosphorylations, whereas RISK inhibitors (wortmannin or U0126) abolished cardioprotection and blocked STAT-3 phosphorylation. In our experimental model, the combination of IPost and RIPer improved cardioprotection through the recruitment of the SAFE pathway. Our findings also indicate that cross talk exists between the RISK and SAFE pathways.

Diagnosis and Treatment of Iron Deficiency in Heart Failure: OFICSel study by the French Heart Failure Working Group.

AIMS: Iron deficiency (ID) occurs in about 50% of patients with heart failure (HF). The European Society of Cardiology (ESC) recommends ID diagnostic testing in newly diagnosed patients with HF and during follow-up, with intravenous iron supplementation (IS) only recommended in patients with HF with reduced ejection fraction (HFrEF). This study aimed to assess prevalence, clinical characteristics, and application of ESC guidelines for ID and IS in patients with HF in the real-life clinical setting. METHODS AND RESULTS: The French transversal multicentre OFICSel registry (300 cardiologists) conducted in 2017 included patients hospitalized for HF at least once in the previous 5 years. Diverse adult patients were eligible including inpatients and outpatients and those with acute and chronic HF. Data were collected from cardiologists and patients using study-specific surveys. Data included demographic and clinical data, as well as HF and ID management data. Overall, 2822 patients, mainly male (69.3%) with a median age of 69 years (interquartile range 58-78), were included. A total of 1075 patients (38.1%) were tested for ID, with 364 (33.9%) diagnosed. Of these, 168 (46.2%) received IS: 128 (76.2%) intravenous IS and 40 (23.8%) oral. Among the 201 patients with HFrEF diagnosed with ID, 99 (49.3%) received IS: 79 (79.8%) intravenous IS and 20 (20.2%) oral. CONCLUSIONS: In clinical practice, only one-third of patients with HF had a diagnostic test for ID. In patients with ID with HFrEF, only 39.3% received intravenous IS as recommended. Thus, in general, cardiologists should be encouraged to follow the ESC guidelines to ensure optimal treatment for patients with HF.