Successful Mechanical Reperfusion Research Articles

Impact of age on the effect of pre-hospital P2Y12 receptor inhibition in primary percutaneous coronary intervention for ST-segment elevation myocardial infarction: the ATLANTIC-Elderly analysis

The aim of the study was to examine the main results of the ATLANTIC trial in patients with ST-elevation myocardial infarction (STEMI), randomised to pre- versus in-hospital ticagrelor, according to age. Patients were evaluated by age class (<75 vs. ≥75 years) for demographics, prior cardiovascular history, risk factors, management, and outcomes. Elderly patients (≥75 years; 304/1,862) were more likely to be women, diabetic, lean, with a prior history of myocardial infarction and CABG, and with comorbidities (p<0.01 for all). Elderly patients presented more frequently with acute heart failure and less frequently had thromboaspiration, a stent implanted (p<0.01) and an aggressive antithrombotic regimen. Elderly patients had lower rates of pre- and post-PCI ≥70% ST-segment elevation resolution (43.9% vs. 51.6%; p=0.035), of pre- and post-PCI TIMI 3 flow (17.1% vs. 27.5%, p=0.0002), and a higher rate of the composite of death/MI/stroke/urgent revascularisation (9.9% vs. 2.9%; OR 3.67, 95% CI [2.27; 5.93], p<0.0001) and mortality (8.5% vs. 1.5%; OR 6.45, 95% CI [2.75; 15.11], p<0.0001). There was a non-significant trend towards more frequent major bleedings among elderly patients (TIMI major 2.3% vs. 1.1%; OR 2.13, 95% CI [0.88; 5.18], p=0.095). There was no significant interaction between time of ticagrelor administration (pre-hospital versus in-lab) and class of age for all outcomes. Elderly patients, who represented one sixth of the patients randomised in the ATLANTIC trial, had less successful mechanical reperfusion and a sixfold increase in mortality at 30 days, probably due to comorbidities and possible undertreatment. The effect of early ticagrelor was consistent irrespective of age.

Privremeni veštački vodič srčanog ritma u terapiji akutnog infarkta miokarda sa ST elevacijom

Left ventricular function is the most important predictor of early and late prognosis of patients with acute myocardial infarction. Another important cause of death during the acute phase is cardiac rhythm and conduction. While tachycardia is treated by a number of antiarrhythmics drugs and electrocardioversion or defibrillation, the greater the problem is bradycardia which disturb hemodynamics or cause the malignant cardiac arrhythmias and asystole. Successful early medication or mechanical reperfusion of infarct affected coronary arteries may prevent the occurrence thereof. In the case of their occurence, there are available a small number of drugs (atropine and aminophylline) and temporary artificial transcutaneous or intravenouse pacing.

Injeção intracoronariana de células tronco após infarto do miocárdio: subestudo da microcirculação

The injection of stem cells in the context of acute myocardial infarction (AMI) has been tested almost exclusively by anterograde intra-arterial coronary (IAC) delivery. The retrograde intravenous coronary (IVC) delivery may be an additional route. To compare the cell distribution and retention pattern in the anterograde and retrograde routes. To investigate the role of microvascular obstruction by magnetic resonance imaging in cell retention by cardiac tissue after the injection of bone marrow mononuclear cells (BMMC) in AMI. This was a prospective, open label, randomized study. Patients with AMI who presented: (1) successful chemical or mechanical reperfusion within 24 hours of symptom onset and (2) infarction involving more than 10% of the left ventricle (LV) at the myocardial scintigraphy were included in the study. One hundred million BMMC were injected into the infarction-related artery through IAC route, or vein through the IVC route. One percent of the injected cells were labeled with 99mTc-hexamethyl-propylene-amine-oxime (99mTc-HMPAO). Cell distribution was evaluated at 4 and 24 hours after the myocardial scintigraphy injection. Cardiac magnetic resonance imaging was performed before cell injection. Thirty patients were randomized into three groups. There were no serious adverse events related to the procedure. The early and late retention of labeled cells was higher in the IAC group than in IVC group, regardless of the presence of microcirculation obstruction. The injection using the retrograde approach was feasible and safe. Cell retention by cardiac tissue was higher using the anterograde approach. More studies are needed to confirm these findings.

Effects of G-CSF on systemic inflammation, coagulation and platelet activation in patients with acute myocardial infarction

Introduction In the prospective, randomised, double-blind, placebo-controlled Regenerate Vital Myocardium by Vigorous Activation of Bone Marrow Stem Ce lls (REVIVAL)-2 trial patients with acute myocardial infarction (AMI) and successful mechanical reperfusion received granulocyte-colony stimulating factor (G-CSF, 10 μg/kg KG s.c.) or placebo for 5 days. Aim of this substudy was to assess the impact of G-CSF on systemic inflammatory and procoagulant responses and platelet activation. Methods and Results Before and five days after G-CSF (n = 56) or placebo (n = 58) circulating cytokine concentrations of interleukin (IL)-1ß, IL-6, IL-8, IL-10, IL-12 and Tumor-Necrosis Factor-α (TNF-α were measured. Prothrombin fragment F1 + 2 and Tissue Factor activity served as a measure for activated coagulation. Platelet activation was characterized by cell surface expression of the activated fibrinogen receptor (PAC-1), P-selectin and CD40L by flow cytometry. Administration of G-CSF was associated with elevated TNF-α and CRPconcentrations compared to the placebo group after 5 days. Other cytokines (IL-1ß, IL-6, IL-8, IL-10, IL-12) were comparable after treatment with G-SCF or placebo. Similarly, circulating prothrombin fragments F1 + 2, TF activity and platelet activation did not differ in both groups. Conclusion Treatment with G-CSF in patients with AMI was associated with enhanced proinflammatory TNF-α and CRP levels but no activation of coagulation.

Prevalence, Predictors, Time Course, and Long-Term Clinical Implications of Left Ventricular Functional Recovery After Mechanical Reperfusion for Acute Myocardial Infarction

This study prospectively evaluated the prevalence, predictors, time course, and prognostic impact of left ventricular (LV) functional recovery after successful primary percutaneous coronary intervention in 228 consecutive patients with acute myocardial infarctions (AMIs) and LV dysfunction. Serial echocardiographic exams were performed within 24 hours (time 1) and at 1 month (time 2) and 6 months (time 3) after AMI. Overall, 133 patients (58%) showed significant LV functional recovery (> or =10% ejection fraction increase compared with time 1 or ejection fraction > or =50%) at time 3. Early (from time 1 to time 2) and late (from time 2 to time 3) functional recovery patterns were detected in 102 patients (45%) and 31 patients (14%), respectively. Independent predictors of LV functional recovery were enzymatic infarct size (p = 0.0001), time from symptom onset to reperfusion (p = 0.022), extent and severity of baseline LV wall motion abnormalities (p = 0.007), and female gender (p = 0.031). Six-month LV remodeling rates were 36% and 64% in patients with and without LV functional recovery (p = 0.0001). The five-year cardiac death rate was significantly lower in patients with LV functional recovery than in those without (8% vs 18%, respectively, p = 0.024). The time course of LV functional recovery during 6 months did not significantly affect long-term survival. In conclusion, after successful mechanical reperfusion of AMIs, nearly half of patients showed poor LV functional recovery. The presence of significant LV functional recovery 6 months after reperfused AMI, but not the specific time course of recovery, is clearly associated with a better long-term clinical outcome. Simple baseline variables can predict the improvement of cardiac function after reperfused AMI.

Stem cell mobilization by granulocyte-colony-stimulating factor in acute myocardial infarction: lessons from the REVIVAL-2 trial

Experimental studies and early-phase clinical trials suggest that mobilization of bone marrow stem cells by granulocyte-colony-stimulating factor (G-CSF) can be used to improve cardiac regeneration after acute myocardial infarction (AMI). In order to more fully evaluate this intervention in patients with AMI, we conducted the Regenerate Vital Myocardium by Vigorous Activation of Bone Marrow Stem Cells (REVIVAL-2) clinical trial. Following successful reperfusion by percutaneous coronary intervention for AMI, patients were randomly assigned to receive a subcutaneous daily dose of 10 microg/kg G-CSF or placebo for 5 days. Treatment with G-CSF produced a significant mobilization of stem cells. After 4-6 months the reduction in infarct size from baseline, as determined by technetium-99-labeled single-photon-emission CT, did not differ significantly between the G-CSF group and the placebo group. Furthermore, the improvement in left ventricular ejection fraction, as assessed by late-enhancement MRI, did not differ significantly between the two groups. G-CSF treatment did not increase the risk of adverse clinical events and did not promote restenosis. Our trial demonstrates that stem cell mobilization by G-CSF does not improve infarct size, left ventricular function, or coronary restenosis in patients with AMI who have had successful mechanical reperfusion.

Impact of mechanical reperfusion on clinical outcome in elderly patients with right ventricular infarction

Previous reports suggest that elderly patients with acute right ventricular infarction suffer in-hospital mortality of 50% and that hemodynamic compromise is irreversible. We hypothesized that mechanical reperfusion would improve such outcomes. We retrospectively analyzed in-hospital morbidity and mortality in 54 patients >70 years of age with acute inferior myocardial infarction undergoing primary angioplasty. The presence of right ventricular infarction was determined by a two dimensional echocardiogram. Overall, 18 (33%) patients had inferior myocardial infarction and right ventricular infarction, whereas 36 (67%) patients had inferior myocardial infarction alone. All patients with inferior myocardial infarction alone were successfully reperfused, whereas one patient with right ventricular infarction suffered reperfusion failure. Right ventricular infarction patients more commonly suffered hemodynamic and arrhythmic complications (hypotension in 33 vs. 2.8%, P<0.01; ventricular arrhythmias in 61 vs. 25%, P<0.01; and bradyarrhythmias in 78 vs. 25%, P<0.01). Overall, 72% of right ventricular infarction patients survived, including many with hemodynamic compromise. In-hospital mortality, however, was greater in those with right ventricular infarction than in those without (28 vs. 8.3%, P=0.19). Elderly patients with inferior myocardial infarction complicated by right ventricular infarction suffer greater morbidity and mortality than those without. With successful mechanical reperfusion, however, the majority survives, including those with hemodynamic compromise.

Stem Cell Mobilization by Granulocyte Colony-Stimulating Factor in Patients With Acute Myocardial Infarction&lt;SUBTITLE&gt;A Randomized Controlled Trial&lt;/SUBTITLE&gt;

Experimental studies and early phase clinical trials suggest that transplantation of blood-derived or bone marrow-derived stem cells may improve cardiac regeneration and neovascularization after acute myocardial infarction. Granulocyte colony-stimulating factor (G-CSF) induces mobilization of bone marrow stem cells. To assess the value of stem cell mobilization by G-CSF therapy in patients with acute myocardial infarction. Randomized, double-blind, placebo-controlled trial of patients diagnosed with ST-segment elevation acute myocardial infarction who had successful reperfusion by percutaneous coronary intervention within 12 hours after onset of symptoms in Germany between February 24, 2004, and February 2, 2005. Patients were randomly assigned to receive subcutaneously either a daily dose of 10 microg/kg of G-CSF or placebo for 5 days. The primary end point was reduction of left ventricular infarct size according to technetium Tc 99m sestamibi scintigraphy performed at baseline and at 4 to 6 months after randomization. Secondary end points included improvement of left ventricular ejection fraction measured by magnetic resonance imaging and the incidence of angiographic restenosis. Of the 114 patients, 56 were assigned to receive treatment with G-CSF and 58 were assigned to receive placebo. Treatment with G-CSF produced a significant mobilization of stem cells. Between baseline and follow-up, left ventricular infarct size according to scintigraphy was reduced by a mean (SD) of 6.2% (9.1%) in the G-CSF group and 4.9% (8.9%) in the placebo group (P = .56) and left ventricular ejection fraction was improved by 0.5% (3.8%) in the G-CSF group and 2.0% (4.9%) in the placebo group (P = .14). Angiographic restenosis occurred in 19 (35.2%) of 54 patients in the G-CSF group and in 17 (30.9%) of 55 patients in the placebo group (P = .79). The most common adverse event among patients assigned to G-CSF was mild to moderate bone pain and muscle discomfort. Stem cell mobilization by G-CSF therapy in patients with acute myocardial infarction and successful mechanical reperfusion has no influence on infarct size, left ventricular function, or coronary restenosis. ClinicalTrials.gov Identifier: NCT00126100.

Stem-cell therapy after acute myocardial infarction: the focus should be on those at risk

In today's Lancet, Stefans Janssens and colleagues report the first randomised double-blind placebo-controlled trial of stem-cell therapy for restoration of ventricular function after myocardial infarction.1 These investigators studied 66 patients presenting with ST-elevation myocardial infarction who had had a successful mechanical reperfusion. All patients subsequently received optimum medical therapy, with over 90% of patients on aspirin, clopidogrel, angiotensin-converting-enzyme inhibitors, β blockers, and statins.

Left Ventricular Remodeling and Systolic Deterioration in Acute Myocardial Infarction: Findings from the Stent‐PAMI Study

Left ventricular systolic deterioration (LVSD) develops in some patients despite successful percutaneous intervention and medical therapy for myocardial infarction (MI). We sought to determine predictors of LVSD by comparing demographic, procedural, angiographic variables, and 6-month major adverse cardiac events (MACE) in patients with and without LVSD after MI. We performed a posthoc analysis of patients prospectively enrolled in the Stent-PAMI trial if they had successful percutaneous intervention for MI (<50% residual stenosis and TIMI-3 grade flow), normal left ventricular systolic function on index ventriculogram, and protocol driven coronary angiography with ventriculography at 6 months. We defined LVSD as an absolute decrease in ejection fraction > or =15% compared to baseline value. Of the 900 patients enrolled in Stent-PAMI, 187 patients met the inclusion criteria. LVSD developed in 30 patients (16%) and occurred independent of demographic, procedural, angiographic variables, and 6-month MACE. Multivariate predictors of LVSD were higher baseline ejection fraction (P = 0.0065, OR 1.09; 95% CI = 1.02-1.16) and peak creatine phosphokinase (CPK) level (P = 0.0022, OR 1.04; 95% CI = 1.02-1.07). LVSD occurs in a minority of patients despite successful mechanical reperfusion and occurred independent of procedural, angiographic variables, target vessel revascularization, reinfarction, and combined MACE. Infarct size (determined by peak CPK) and high baseline ejection fraction predicted development of LVSD at 6 months. LVSD in this population likely occurred by negative left ventricular remodeling.

Correlation between ECG and myocardial perfusion after mechanical reperfusion of acute myocardial infarction

The identification of viable myocardium after myocardial infarction (MI) carries major prognostic impact. Due to myocardial stunning early after successful mechanical reperfusion of acute myocardial infarction, analysis of myocardial perfusion but not of contractile function can be used to differentiate between necrotic and viable myocardium. Although being widely regarded as an indicator of infarct transmurality, the relation between post-infarct Q-wave formation and the amount of viable myocardium has not been studied. We hypothesized that there was a correlation between the extent of Q-wave formation and the extent of perfusion abnormalities on myocardial contrast echocardiography early after successful mechanical reperfusion of first acute myocardial infarction and that the extent of post-infarct Q-wave formation might therefore be used as a simple estimate of the amount of viable myocardium. Methods and results 47 patients with first MI and treated by direct PCI were enrolled. Patients were divided into 3 groups according the presence and number of abnormal Q waves (group A—no abnormal Q wave; group B—≤2 abnormal Q waves, group C—≥3 abnormal Q waves). Left ventricular pumpfunction was defined by ejection fraction (EF) on ventriculography and wall motion score index (WMSI) on echocardiography. Myocardial perfusion was defined by perfusion score index (PSI) on myocardial contrast echocardiography. Patients in group A had significantly better LV function than patients in other groups [EF 57 ± 5 vs. 48 ± 11% (group B) and 47 ± 10% (group C); p < 0.05], also WMSI was the best in this group [1.34 ± 0.22 vs. 1.67 ± 0.39 (group B) and 1.68 ± 0.31 (group C); p < 0.01]. Myocardial perfusion assessed by PSI was best in group A (1.2 ± 0.3, p < 0.05). With respect to PSI, there was a significant difference between group B and C (1.41 ± 0.21 vs. 1.56 ± 0.29; p < 0.05), even though EF and WMSI did not differ in these groups. The amount of perfused segments with severe wall motion abnormality was higher in group B compared to group C (47% vs. 25%; p < 0.05). Conclusion In patients after successful mechanical reperfusion of first MI, the extent of Q-wave formation on ECG may be regarded as a corollary of the amount of myocardial microvascular damage and may, therefore, be used to estimate the amount of viable myocardium post-infarct.

Impact of ST-segment depression resolution on mortality after successful mechanical reperfusion in patients with ST-segment elevation acute myocardial infarction

The aim of the present study was to evaluate the additional prognostic effect of ST-depression resolution in 610 patients who had ST-elevation myocardial infarction and underwent successful primary angioplasty (postprocedural Thrombolysis In Myocardial Infarction 3 flow and complete resolution of ST-segment elevation). Incomplete resolution of ST-segment depression (<70%) was observed in 50 patients (8.2%). These patients were older, had a higher Killip's class at presentation, had larger infarcts, and had an increased 1-year mortality (10% vs 2%, p = 0.0004). At multivariate analysis, incomplete resolution of ST-segment depression was an independent predictor of 1-year mortality (p = 0.028).

ST resolution after mechanical reperfusion closely correlates with myocardial salvage and associtated with patients prognosis after acute anteroseptal MI

Background: Early resolution of ST-segment elevation is an indicator of final infarct size and clinical outcomes. However, the relationship between the degree of ST resolution and the indexes derived from perfusion scintigraphy such as area at risk(AAR), infarct size(IR), and salvaged myocardium(SI) is unclear. Methods: Consecutive 65 patients with anteroseptal myocardial infarction with successful mechanical reperfusion, whose AAR, IS, and SI could be assessed by myocardial perfusion imaging, were studied. Serial 12 leads electrocardiograms were performed at baseline, 90 minutes after reperfusion. ST resolution was defined as complete (>70%, n = 16), partial (<70% to 30%, n = 36), or no resolution (<30%, n = 13). Results: Patients with no resolution group tended to be longer time to reperfusion (complete: 4.0 ± 7.5 partial: 6.5 ± 8.2 No: 7.4 ± 6.6). Peak CPK inversely correlated with level of ST resolution(complete:1689 ± 1395 partial:3078 ± 2577 No:5252 ± 2537 p < 0.01). As for the scintigraphical indexes such as AAR, IR, and SI, all these indexes had significant association with the level of ST resolution(AAR: complete 114 ± 54 partial 145 ± 58 no 178 ± 51 p < 0.05, IS:complete 21 ± 26 partial 66 ± 60 no 131 ± 31 p < 0.001, SI: complete 81.9 ± 16.2 partial 57.6 ± 29.4 no 27.7 ± 23.9 p < 0.001). Furthermore, patients with no resolutions experienced high prevalence of the occurrence of congestive heart failure than partial and complete resolution groups. Conclusion: Early resolution of ST-segment elevation closely correlated with AAR, IS, and SI as assessed by scintigraphy and closely associated with patients prognosis.

Clinical significance of in-hospital reocclusion after mechanical reperfusion and percutaneous transluminal coronary angioplasty for acute myocardial infarction.

To analyze the effects of in-hospital reocclusion of reperfused AMI culprit coronary arteries in mortality and to identify the predictors. The present study comprises a sample of 155 patients with AMI who underwent successful mechanical reperfusion by direct coronary angioplasty and angiographic control during hospitalization or before discharge. Patients were classified into group A: reoccluded patients (n=30) and group B: non-reoccluded patients (n=125). We identified in-hospital reocclusion predictors and found a greater significance in mortality among reoccluded patients (23,3% x 1.6%; p=0.00004). Silent reocclusion or typical angina at reocclusion had a good prognosis. The independent predictors of in-hospital mortality were hypertension, multiarterial lesions, totally occluded AMI culprit lesions, failed redilatation, failed redilatation in comparison with no intention to redilate, no redilatation in comparison with no attempt to redilate, and reocclusion within the first 48 to 72 hours. The decision to redilate, independently of the result, led to a 50.0% reduction in hospital mortality (p=0.0366). In-hospital AMI culprit coronary artery reocclusion had an adverse effect similar to that reported in clinical studies with high mortality rates (23.3% x 1.6%; p=0.00004). The major contribution of this study is to recommend the reopening of reoccluded AMI culprit coronary arteries as a means for the management of coronary artery reocclusion.