Long-term impact of postconditioning on infarct size and left ventricular ejection fraction in patients with ST-elevation myocardial infarction

Background: Ischemic postconditioning (PostC), reperfusion in brief cycles, is known to induce short-term reduction in infarct size in patients with ST elevation myocardial infarction (STEMI), especially among those with large myocardium at risk (MaR). The aim of the present study was to investigate the long-term effect of PostC on infarct size and left ventricular ejection fraction (LVEF). Methods: Sixty-eight patients with a first STEMI were randomised to primary percutaneous coronary intervention (PCI) (n = 35) or PCI followed by PostC (n = 33). MaR was determined as abnormally contracting segments on left ventricular angiogram. Cardiac magnetic resonance was performed at 3 and 12 months for the determination of infarct size and LVEF. Results: Overall there was no difference in infarct size expressed in percentage of MaR between patients randomised to the control (31%; 23, 41) and PostC (31%; 23, 43) groups at 12 months. Likewise there was no difference in LVEF between control (49%; 41, 55) and PostC (52%; 45, 55). In contrast, patients in the PostC group with MaR in the upper quartile had a significantly smaller infarct size (29%; 18, 38) than those in the control group (40%; 34, 48; p < 0.05) at 12 months. In these patients LVEF was higher in the PostC (47%; 43, 50) compared to the control group (38%; 34, 42; p < 0.01). Conclusions: In this long-term follow-up study PostC did not reduce infarct size in relation to MaR or improved LVEF in the overall study population. However, the present data suggest that PostC exerts long-term beneficial effects in patients with large MaR thereby extending previously published short-term observations

Myocardium at risk by magnetic resonance imaging: head-to-head comparison of T2-weighted imaging and early gadolinium enhanced steady state free precession

AIMS: To determine the myocardial salvage index, the extent of infarction needs to be related to the myocardium at risk (MaR). Thus, the ability to assess both infarct size and MaR is of central clinical and scientific importance. The aim of the present study was to explore the relationship between T2-weighted cardiac magnetic resonance (CMR) and contrast-enhanced steady-state free precession (CE-SSFP) CMR for the determination of MaR in patients with acute myocardial infarction. METHODS AND RESULTS: Twenty-one prospectively included patients with first-time ST-elevation myocardial infarction underwent CMR 1 week after primary percutaneous coronary intervention. For the assessment of MaR, T2-weighted images were acquired before and CE-SSFP images were acquired after the injection of a gadolinium-based contrast agent. For the assessment of infarct size, late gadolinium enhancement images were acquired. The MaR by T2-weighted imaging and CE-SSFP was 29 ± 11 and 32 ± 12% of the left ventricle, respectively. Thus, the MaR with T2-weighted imaging was slightly smaller than that by CE-SSFP (-3.0 ± 4.0%; P < 0.01). There was a significant correlation between the two MaR measures (r(2)= 0.89, P < 0.01), independent of the time after contrast agent administration at which the CE-SSFP was commenced (2-8 min). CONCLUSION: There is a good agreement between the MaR assessed by T2-weighted imaging and that assessed by CE-SSFP in patients with reperfused acute myocardial infarction 1 week after the acute event. Thus, both methods can be used to determine MaR and myocardial salvage at this point in time

Circulating endothelial and platelet derived microparticles reflect the size of myocardium at risk in patients with ST-elevation myocardial infarction

Objectives: Microparticles (MP) are small membrane vesicles, released from activated, damaged and apoptotic endothelial cells (EMP) or platelets (PMP) that may actively modulate inflammation, coagulation and vascular function. We tested the hypothesis that the number of circulating EMP or PMP in acute myocardial infarction correlates with the myocardium at risk (MaR) and infarct size (IS). Methods: EMP were quantified in plasma samples of 36 patients (age: 63 +/- 10 years) with first time ST-elevation myocardial infarction (STEMI) using flow cytometry. EMP were defined as CD31(+)/CD42(-) MP and CD144(+) MP and PMP as CD31(+)/CD42(+) MP. MaR and IS was determined by cardiovascular magnetic resonance imaging one week after the index event. Results: Plasma levels of CD31(+)/CD42(-) EMP were 251.0 +/- 178.8/mu l and CD144(+) 106.3 +/- 33.7/mu l. PMP levels were 579.2 +/- 631.8/mu l. MaR was 31.0 +/- 11.2% of the left ventricle and IS was 11.4 +/- 7.1% of the left ventricle. Patients with STEMI in the left anterior descending artery had higher levels of CD31(+)/CD42(-) EMP and PMP than those with other infarct-related arteries (p<0.05). The numbers of CD31(+)/CD42(-) EMP and PMP correlated to MaR, but not to IS. Conclusions: Circulating EMP and PMP correlate to the size of MaR in patients with STEMI suggesting that they reflect the severity of the endothelial injury and platelet activation during myocardial ischemia. (C) 2011 Elsevier Ireland Ltd. All rights reserved

Implantable cardiac devices in adult patients with repaired tetralogy of Fallot

Objectives: Implantable cardiac devices are common in patients with tetralogy of Fallot (ToF) (18.3–21.3%) according to previous reports from large centres. We conducted this study to investigate the prevalence and incidence of cardiac devices in a less selected population of patients with ToF and assess factors other than arrhythmia associated with having a device.  Design: 530 adult (≥18 years) patients with repaired ToF were identified in the national registry of congenital heart disease (SWEDCON) and matched with data from the Swedish pacemaker registry. Patients with implantable cardiac devices were compared with patients without devices.  Results: Seventy-five patients (14.2%) had a device; 51 (9.6%) had a pacemaker and 24 (4.5%) had an implantable cardioverter defibrillator. The incidence in adult age (≥18 years) was 5.9/1000 patient years. Estimated device free survival was 97.5% at twenty, 87.2% at forty and 63.5% at sixty years of age. Compared with previous studies, the prevalence of devices was lower, especially for ICD. In multivariate logistic regression, cardiovascular medication (odds ratio [OR] 3.5, 95% confidence interval [CI] 1.8–6.8), impaired left ventricular function, (OR 2.6, 95%CI 1.3–5.0) and age (OR 1.02, 95%CI 1.002–1.05) were associated with having a device.  Conclusion: The prevalence of devices in our population, representing a multicenter register cohort, was lower than previously reported, especially regarding ICD. This can be due to differences in treatment traditions with regard to ICD in this population, but it may also be that previous studies have reported selected patients with more severe disease

Effect of Postconditioning on Infarct Size in Patients With ST-elevation Myocardial Infarction

Background Small studies suggest that postconditioning reperfusion interrupted by brief repetitive cycles of reocclusions, may protect the myocardium in the clinical setting. Objective To test the hypothesis that postconditioning limits infarct size in relation to the area at risk in patients with ST elevation myocardial infarction (STEMI). Methods 76 patients (aged 37-87 years) eligible for primary percutaneous coronary intervention due to STEMI were randomised to standard percutaneous coronary intervention (n=38) or postconditioning, consisting of four cycles of 60 s reperfusion and 60 s of reocclusion before permanent reperfusion (n=38). Results The area at risk was determined from angiographic abnormally contracting segments. Infarct size was quantified from delayed enhancement MRI on days 6-9. Infarct size, expressed in relation to the area at risk, did not differ between the control group (44%; 30, 56) (median and quartiles) and the post-conditioned group (47%; 23, 63). The slope of the regression lines relating infarct size to the area at risk differed between the two groups. Infarct size was significantly (p=0.001) reduced by postconditioning in patients with large areas at risk. The area under the curve and peak troponin T release and CKMB during 48 h did not differ between patients in the control and postconditioning groups. Conclusions This prospective, randomised trial suggests that postconditioning does not reduce infarct size in patients with STEMI in the overall study group. The data indicate that postconditioning may be of value in patients with large areas at risk

Helicobacter pylori and Pro-Inflammatory Protein Biomarkers in Myocardial Infarction with and without Obstructive Coronary Artery Disease

Myocardial infarction (MI) with obstructive coronary artery disease (MI-CAD) and MI in the absence of obstructive coronary artery disease (MINOCA) affect different populations and may have separate pathophysiological mechanisms, with greater inflammatory activity in MINOCA compared to MI-CAD. Helicobacter pylori (Hp) can cause systemic inflammation and has been associated with cardiovascular disease (CVD). We aimed to investigate whether Hp infection is associated with concentrations of protein biomarkers of inflammation and CVD. In a case-control study, patients with MINOCA (n = 99) in Sweden were included, complemented by matched subjects with MI-CAD (n = 99) and controls (n = 100). Protein biomarkers were measured with a proximity extension assay in plasma samples collected 3 months after MI. The seroprevalence of Hp and cytotoxin-associated gene A (CagA) was determined using ELISA. The associations between protein levels and Hp status were studied with linear regression. The prevalence of Hp was 20.2%, 19.2%, and 16.0% for MINOCA, MI-CAD, and controls, respectively (p = 0.73). Seven proteins were associated with Hp in an adjusted model: tissue plasminogen activator (tPA), interleukin-6 (IL-6), myeloperoxidase (MPO), TNF-related activation-induced cytokine (TRANCE), pappalysin-1 (PAPPA), soluble urokinase plasminogen activator receptor (suPAR), and P-selectin glycoprotein ligand 1 (PSGL-1). Hp infection was present in one in five patients with MI, irrespective of the presence of obstructive CAD. Inflammatory proteins were elevated in Hp-positive subjects, thus not ruling out that Hp may promote an inflammatory response and potentially contribute to the development of CVD