Reperfused ST-elevation Myocardial Infarction Research Articles

Regional functional recovery after acute myocardial infarction: a cardiac magnetic resonance long-term study

We sought to analyze the trend of functional recovery after successful reperfused ST-elevation myocardial infarction (STEMI) in an optimally treated patient group over a 14 month follow-up in relation to ischemia-time and the presence of microvascular obstruction (MVO). First-pass perfusion-, cine- and late enhancement (LE)- cardiac MR were performed in 40 patients (33 male and 7 female, 54.8 ± 12.3 years) within 6 days as well as 4 and 14 months after successful primary percutaneous coronary intervention for STEMI. Significant recovery of segmental wall thickening (SWT %) occurred exclusively in infarcted segments reperfused within 4 h after symptom onset (group 1 with pain-to-balloon time <2 h: 59 ± 4 to 70 ± 4%; P < 0.02) (group 2 with pain-to-balloon-time 2-4 h: 51 ± 4 to 59 ± 3%, P < 0.05) during the first 4 months, whereas changes thereafter were not significant (P = NS). Infarcted segments with MVO showed lowest regional myocardial function at any time of assessment (all P < 0.001) and a lack of significant recovery during the study period. Significant recovery of regional myocardial function is related to rapid revascularization of the infarct-related artery and the absence of MVO. Improvement of SWT occurred exclusively within the first 4 months after acute myocardial infarction and remained unchanged thereafter.

439 Impact of the type and timeliness of reperfusion on left ventricular dysfunction amongst survivors of ST elevation myocardial infarction (STEMI) within a regional model of stemi care: Insights from the vancouver coastal health authority STEMI initiative

439 Impact of the type and timeliness of reperfusion on left ventricular dysfunction amongst survivors of ST elevation myocardial infarction (STEMI) within a regional model of stemi care: Insights from the vancouver coastal health authority STEMI initiative

Prognostic Value and Determinants of a Hypointense Infarct Core in T2-Weighted Cardiac Magnetic Resonance in Acute Reperfused ST-Elevation–Myocardial Infarction

A hypointense core of infarcted myocardium in T2-weighted cardiovascular MRI (CMR) has been used as a noninvasive marker for intramyocardial hemorrhage. However, the clinical significance of such findings not yet been established. The aim of this study was to evaluate determinants and prognostic impact of a hypointense infarct core in T2-weighted CMR images, studied in patients after acute, reperfused ST-elevation-myocardial infarction. We analyzed 346 patients with ST-elevation-myocardial infarction undergoing primary angioplasty < 12 hours after symptoms onset. T2-weighted, contrast-enhanced CMR was used for assessment of the area at risk, myocardial salvage, infarct size, hypointense core in T2-weighted images, and late microvascular obstruction. Patients were categorized into 2 groups defined by the presence or absence of a hypointense core. The primary end point of the study was occurrence of major adverse cardiovascular events defined as death, reinfarction, and congestive heart failure within 6 months after infarction. A hypointense core was present in 122 (35%) patients and was associated with larger infarcts, greater amount of microvascular obstruction, less myocardial salvage, and impaired left ventricular function (P < 0.001, respectively). The presence of a hypointense core was a strong univariable predictor of major adverse cardiovascular events (hazard ratio, 2.59; confidence interval, 1.27 to 5.27) and was significantly associated with an increased major adverse cardiovascular events rate (16.4% versus 7.0%, P = 0.006) 6 months after infarction. A hypointense infarct core within the area at risk of reperfused infarcted myocardium in T2-weighted CMR is closely related to infarct size, microvascular obstruction, and impaired left ventricular function, with subsequent adverse clinical outcome.

LONG-TERM PROGNOSTIC VALUE OF MYOCARDIAL SALVAGE ASSESSED BY CARDIOVASCULAR MAGNETIC RESONANCE IN ACUTE REPERFUSED MYOCARDIAL INFARCTION

Objective In acute myocardial infarction, cardiovascular magnetic resonance (CMR) allows for quantifying the extent of salvaged myocardium after reperfusion as a potential strong end point for clinical trials. The aim of this study was to investigate whether the early prognostic significance of myocardial salvage assessed by CMR is sustained at long-term clinical follow-up in patients with ST-elevation myocardial infarction (STEMI) undergoing primary angioplasty. Design, setting, patients We analysed 208 consecutive patients with STEMI undergoing primary angioplasty Results The median MSI was 48 (IQR 27 to 73). Long-term follow-up was available in 202 patients (97%) at a median of 18.5 months (IQR 13.8 to 20.8). Major adverse cardiovascular events occurred in 33 patients (16%), with a significantly lower event rate in the MSI ≥ median group (7 vs 26 events, p Conclusions MSI assessed by CMR predicts long-term clinical outcome in acute reperfused STEMI. Therefore, our data support the use of myocardial salvage as an end point for clinical trials investigating novel reperfusion strategies. Trial registration number http://www.ClinicalTrials.gov: NCT00952224.

Determinants of microvascular damage recovery after acute myocardial infarction: results from the acute myocardial infarction contrast imaging (AMICI) multi-centre study

Microvascular damage (MD) occurring soon after primary percutaneous coronary intervention (PPCI) may reverse or remain sustained within the first week after ST-elevation myocardial infarction (STEMI). We investigated the incidence, determinants, and long-term clinical relevance of MD reversal after PPCI. Serial two-dimensional echocardiograms (2DE) and a myocardial contrast study were obtained within 24 h of PPCI (T1) and at pre-discharge (T2) in 110 successfully re-perfused STEMI patients. Six months 2DE and 2-year clinical follow-up were obtained. After PPCI myocardial re-perfusion was normal at T1 only in 40 patients (36%, 'normal reflow'), recovered at T2 in 33 (30%, 'reversible MD'), and remained abnormal in 37 (34%, 'sustained MD'). At follow-up, normal reflow and reversible MD were coupled with a significant reduction in the infarct area, decrease in cardiac volumes, and a slight non-significant improvement in systolic function. Conversely, in the sustained MD group, the infarct area did not change and cardiac volumes significantly increased with a parallel worsening in systolic function. By multivariate analysis, independent predictors of reversible MD were: absence of family history of coronary artery disease (CAD), younger age, shorter time to re-perfusion, and absence of diabetes. The 2-year combined events rate was significantly lower in reversible MD (log-rank test P= 0.03) compared with sustained MD patients. In STEMI patients treated according to the current guidelines, MD frequently occurs soon after re-perfusion but it is reversible in ~50% of cases and it is associated with a favourable functional and clinical outcome. Family history of CAD, aging, time to re-perfusion, and diabetes are independent predictors of MD reversibility.

Growth-differentiation factor 15 as predictor of mortality in acute reperfused ST-elevation myocardial infarction: insights from cardiovascular magnetic resonance

ObjectiveGrowth-differentiation factor 15 (GDF-15), a stress-responsive member of the transforming growth factor beta cytokine superfamily, has emerged as a biomarker of increased mortality in cardiovascular disease. However, the exact pathophysiological...

Prognostic value and determinants of a hypointense core in T2-weighted cardiac magnetic resonance in acute reperfused ST-elevation myocardial infarction

A hypointense core of infarcted myocardium in T2-weighted CMR has been used as a noninvasive marker for intramyocardial hemorrhage and was related with adverse remodelling in recently published clinical trials. However, the clinical significance of such findings is not yet established.

Gender differences in myocardial salvage and clinical outcome in patients with acute reperfused ST-elevation myocardial infarction

There is conflicting evidence regarding gender-based differences in outcomes in patients after myocardial infarction. Recently, a study demonstrated greater myocardial salvage assessed with SPECT imaging in women than in men. However, SPECT imaging has several limitations including its low spatial resolution particularly of subendocardial infarcts and as a result cardiac magnetic resonance imaging (CMR) has emerged as the reference method to assess myocardial salvage.

Early Reperfusion in STEMI Influences Transmural Injury Characteristics and Electrocardiographic Manifestations

Background: Transmural injury in myocardial infarction (MI) has been regarded to develop Q wave. However, early reperfusion seemes to modify geometry of myocardial fibrosis. Thus, we assesses hypothesis that early reperfusion during acute MI may influence transmural injury patterns and Q wave manifestations on electrocardiogram (ECG). Methods and Results: Total 25 patients with anterior wall ST elevation myocardial infarction (STEMI) (58±12 years, male 84%) were enrolled in this study. All underwent cardiac magnetic resonance (CMR) and ECG 14±10 days after reperfusion therapy with direct percutaneous coronary intervention (PCI) (n=23, 92%) and thrombolytics (n=2, 8%). Transmurality patterns in CMR were divided into two types, diffuse and patchy (mottled or islets). Presence of Q wave and fragmented QRS (fQRS) complex in precordial leads were analyzed. All showed transmural enhancement in CMR (percentage enhanced area: 32±2%). Q wave was observed in 28% and non Q wave group was in 72%. 6 of 7 (86%) patients with Q wave group had diffuse pattern. All patients with non-Q wave showed patchy pattern including mottled (n=12, 67%) and islets (n=6, 33%). 15 of 18 (83%) patients with non-Q wave had fQRS in V1∼V5. Transmurality pattern showed differenent between two groups (diffuse pattern: 86% in Q wave group vs patchy pattern: 100% in non Q wave group; p=0.001). Conclusions: Early reperfusion in STEMI affects transmural injury patterns and Q wave manifestations.

002 Rapid improvement in reperfusion strategy in europe: temporal trends in performance measures for reperfusion therapy in ST elevation myocardial infarction

Rate and type of reperfusion, and delay to reperfusion are related to mortality and used as performance measures (PM) in ST elevation myocardial infarction (STEMI). Improvements in PM contribute to reduced mortality. Litte information exists about the improvement of PM in clinical practice in Europe. Euro Heart Survey ACS-III dataset. We selected patients (pts) with STEMI eligible for reperfusion. Pts were divided into 4 periods of 6 months, by date of admission. Rate and type of reperfusion, plus door-to-needle and -artery times were compared between periods. Timely reperfusion was defined as a door-to needle time<30 minutes (min) or a door to artery time <90 min. Independent predictors of timely reperfusion were determined by logistic regression. 7655 had STEMI and were eligible for reperfusion. Overall reperfusion rate increased from 79.2 to 82.3% from period 1 to 4, with primary percutaneous coronary intervention (P-PCI) in 69.9% and thrombolytic therapy (TT) in 20.8%. There was a significant decrease in use of TT (25.4 to 17.3%) & an increase in P-PCI (70.4 to 79.3%) (p < 0.001 for trend). Door-to-needle and -artery times decreased significantly, from 20 to 11 min (p = 0.01) and from 60 to 45 min (p < 0.0001) respectively. The number of pts reperfused in a timely manner increased from 66.7 to 77.6% (p < 0.0001). Independent predictors of timely reperfusion were: Killip class >2, increased systolic blood pressure on admission, female sex, admission to high volume center and admission period. In-hospital mortality decreased from 8.1% to 6.6%, p = 0.047. In Europe, from 2006 to 2008, PM for reperfusion in STEMI improved significantly, particularly reperfusion rate, with more use of PCI. The rate of patients reperfused in a timely manner also increased, through a significant reduction in door to needle and door to artery times. Associated with these improvements, we observed a significant decrease of hospital mortality from 8.1% to 6.6%.

Telemedicine fighting acute coronary syndromes

Introduction Telemedicine allows exchange of information and has therefore become an important tool for optimizing patient treatment in the field of cardiology. Transmission of electrocardiograms (ECGs) from the prehospital setting to the receiving hospital is the most widespread technology in the prehospital setting. Providing a diagnostic ECG from patients with acute coronary syndromes to health care professionals with decision-making power has proven pivotal for an early diagnosis, ideal triage, and initiation of reperfusion therapy of the large group of patients presenting with ST-elevation myocardial infarction (STEMI). This urgent triage could be expanded to several diagnosis in cardiology, primarily the non–ST-elevation presenters. Purpose The purpose of the present article is to briefly describe the history the teletransmitted ECG and some of the recent results obtained when used in routine practice for acute triage and referral for primary percutaneous coronary intervention. Conclusions Transmitting 12-lead ECGs from the community directly to attending cardiologists should become routine. Time to reperfusion in STEMI has decreased, explaining much of the observed decrease in STEMI mortality. This technology allows for increasingly complex and individualized prehospital medical care and could be expanded to a broader number of cardiovascular diagnoses.

Reperfusion strategy in Europe: temporal trends in performance measures for reperfusion therapy in ST-elevation myocardial infarction

The rate and type of reperfusion, as well as time delays to reperfusion are directly associated with mortality and are established as performance measures (PMs) in the treatment of ST elevation myocardial infarction (STEMI). To date, little information exists about PMs for reperfusion in clinical practice in Europe and their temporal changes. Using the Euro Heart Survey ACS-III data set (2 years of inclusions between 2006 and 2008, 138 centres in 21 countries), we selected patients with STEMI eligible for reperfusion therapy. Recorded variables corresponded to the CARDS data set. The rate and type of reperfusion, as well as door to needle and door to artery times were assessed and compared between periods. Timely reperfusion was defined as a door to needle time < 30 min, or a door to artery time < 90 min. We assessed changes in PMs for reperfusion over the 2 years of recruitment. Among 19 205 patients included in the registry, 7655 had STEMI, and 6481 were admitted within the first 12 h and eligible for reperfusion. The rate of patients who underwent reperfusion increased from 77.2 to 81.3%, with an increase in the use of primary percutaneous coronary intervention (P-PCI). The door to needle and door to artery times decreased significantly during the study period, from 20 to 15 min (P = 0.0011) and from 60 to 45 min (P < 0.0001) respectively. As a result, the number of eligible patients receiving reperfusion therapy in a timely manner increased from 53.1 to 63.5% (P < 0.0001). In parallel, over the 2-year period, in-hospital mortality decreased from 8.1 to 6.6% (P = 0.047). In centres participating in the Euro Heart Survey ACS III, PMs for reperfusion in STEMI improved significantly between 2006 and 2008, with greater use of PCI. Similarly, the rate of patients reperfused in a timely manner also increased, with a significant reduction in door to needle and door to artery times.

Right ventricular involvement in anterior myocardial infarction: a translational approach

The aim of the present study was to evaluate the involvement of the right ventricle (RV) in reperfused anterior ST-elevation myocardial infarction (STEMI). Left anterior descending (LAD)-perfused area (using thioflavin-S staining after selective infusion in proximal LAD artery, %), infarct size (using triphenyltetrazolium chloride staining, %), and salvaged myocardium (% of LAD-perfused area) in the right and left ventricle (LV) were quantified in a 90-min LAD occlusion 3-day reperfusion model in swine (n = 8). Additionally, we studied, using cardiovascular magnetic resonance, 20 patients with a first STEMI due to proximal LAD occlusion treated with primary angioplasty. Area at risk (T2-weighted sequence, %), infarct size (late enhancement imaging, %), and salvaged myocardium (% of area at risk) in the right and LV were quantified. In swine, a large LAD-perfused area was detected both in the right and LV (30 +/- 5 vs. 62 +/- 15%, P< 0.001) but more salvaged myocardium (94 +/- 6 vs. 73 +/- 11%, P< 0.001) resulted in a smaller right ventricular infarct size (2 +/- 1 vs. 16 +/- 5%, P< 0.001). Similarly, in patients a large area at risk was detected both in the right and LV (34 +/- 13 vs. 43 +/- 12%, P = 0.02). More salvaged myocardium (94 +/- 10 vs. 33 +/- 26%, P < 0.001) resulted in a smaller infarct size (2 +/- 3 vs. 30 +/- 16%, P< 0.001) in the RV. In reperfused extensive anterior STEMI, a large area of the RV is at risk but the resultant infarct size is small.

Prognostic Significance of Acute Kidney Injury After Reperfused ST-Elevation Myocardial Infarction: Synergistic Acceleration of Renal Dysfunction and Left Ventricular Remodeling

Background Acute kidney injury (AKI) after myocardial infarction is associated with poor clinical outcome. However, mechanisms of the adverse effect of AKI on clinical outcome after reperfused ST-elevation myocardial infarction (STEMI) have not been fully elucidated. Methods and Results We examined 141 consecutive patients with reperfused first anterior STEMI. AKI was defined as an increase in serum creatinine of ≥0.3 mg/dL within 48 hours after admission. Patients with AKI had higher incidence of in-hospital cardiac death ( P = .0004) and major adverse cardiac events (MACE, P = .020) during a mean of 39 ± 40 (range, 1 to 96) months than those without, in association with adverse left ventricular (LV) remodeling. White blood cell count on admission and peak C-reactive protein were higher in patients with than those without AKI. Plasma norepinephrine on admission, interleukin-6, brain natriuretic peptide, and malondialdehyde-modified low-density lipoprotein 2 weeks after STEMI were higher in patients with AKI than those without AKI. Cox proportional hazards model analysis revealed AKI was an independent predictor of MACE (hazard ratio = 2.38, P = .019). Conclusions AKI was a strong predictor of MACE in association with adverse LV remodeling. Enhanced inflammatory response, oxidative stress, and neurohormonal activation may synergistically accelerate renal dysfunction and LV remodeling after STEMI.

Broadening Our Understanding of Survival After Myocardial Infarction

As clinicians and scientists, it is common to presume that clinical outcomes after myocardial infarction (MI) are most profoundly influenced by the pathogenesis of the disease itself, including genetics, cardiovascular risk factors, inflammatory state, disease severity (eg, the number and severity of obstructed coronary arteries), and the treatments that we offer. Consequently, our efforts to optimize the outcomes of our patients are aimed at following clinical guidelines in care for individual patients.1–3 When our profession seeks to influence systems of care and public policy, our focus has been on increasing access to lifesaving therapies.4 Because they appear outside of physicians’ locus of control, risk factors related to patients’ socioeconomic status are often not considered targets for intervention. Article see p 375 Although numerous studies have defined an adverse association between lower socioeconomic status and post-MI treatment5 and outcomes,6–8 little work has been done to develop interventions to overcome these disparities. We also have not sought to systematically understand mediating factors that may influence the prognostic associations of socioeconomic risk factors with outcomes. The reasons there have been such little progress in overcoming socioeconomic status barriers, despite the national priorities to create equity in health care,9–11 are multifactorial and include both the difficulties in measuring socioeconomic status and the challenges in overcoming them. In a critical review of the science linking socioeconomic status to health outcomes, Braveman and colleagues12 demonstrated that different measures of socioeconomic status are not interchangeable, …

Impact of Systemic Acidosis on the Development of Malignant Ventricular Arrhythmias After Reperfusion Therapy for ST-Elevation Myocardial Infarction

The aim of the present study was to examine the effect of systemic acidosis on the development of malignant ventricular arrhythmias, including sustained ventricular tachycardia and ventricular fibrillation (VT/VF), after reperfused ST-elevation myocardial infarction (STEMI). A total of 157 consecutive patients with a reperfused STEMI were examined. Patients were divided into 2 groups according to the presence or absence of systemic acidosis, defined as arterial blood pH <7.40 on admission. Serum creatine kinase and C-reactive protein (CRP) levels were serially measured. Systemic acidosis was observed in 53 patients (34%). There was no significant difference in coronary risk factors and arrival time from onset between the 2 groups. Estimated glomerular filtration rate (eGFR) on admission was lower in patients with acidosis than in those without (P=0.001). Patients with acidosis had a higher incidence of VT/VF (26% vs 4%, P<0.0001), especially within 48 h after STEMI (23% vs 3%, P=0.0002), than those without. The peripheral white blood cell count on admission was higher in patients with than in those without acidosis. Multivariate analysis showed that systemic acidosis was a strong independent predictor of VT/VF (relative risk =8.79, P=0.002) among variables including prior MI and eGFR <60 ml . min(-1) . 1.73 m(-2). Systemic acidosis was a significant determinant of VT/VF after reperfused STEMI and was associated with elevated serum CRP level. Systemic acidosis and subsequent inflammation after ischemia reperfusion may play an important role in the development of VT/VF.

Acute coronary syndrome registry from four large centres in United Arab Emirates (UAE-ACS Registry)

ObjectiveTo identify the characteristics, treatments and hospital outcomes of patients diagnosed as having acute coronary syndrome (ACS) in the United Arab Emirates (UAE).DesignA 3-year prospective registry.SettingFour tertiary care hospitals in...

Reproducibility of myocardial salvage index in acute myocardial infarction by cardiac magnetic resonance imaging - validation against an angiographic score

Methods In 20 patients with reperfused ST-elevation myocardial infarction breath-hold T2-weighted (area at risk [AAR]) and delayed enhancement (infarct size [IS]) images were acquired repeatedly on 2 consecutive days to assess myocardial salvage index (AAR-IS/AAR). Reproducibility, interobserver, and intraobserver variabilities were assessed and compared by Bland-Altman methods. In addition, the AAR at risk in % of left ventricle (%LV) determined by MRI was compared to an angiographic AAR score.

Growth-differentiation factor-15 as predictor of mortality in acute reperfused ST-elevation myocardial infarction: Insights from cardiovascular magnetic resonance

Growth-differentiation factor-15 as predictor of mortality in acute reperfused ST-elevation myocardial infarction: Insights from cardiovascular magnetic resonance

B-type Natriuretic Peptide as Predictor of Heart Failure in Patients with Acute ST Elevation Myocardial Infarction, Single-vessel Disease, and Complete Revascularization: Follow-up Study

To assess the concentration of B-type natriuretic peptide (BNP) as a predictor of heart failure in patients with acute ST elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PCI) with successful and complete revascularization. Out of a total of 220 patients with acute STEMI admitted to the Sisters of Mercy University Hospital in the period January 1 to December 31, 2007, only patients with acute STEMI undergoing primary PCI who had single vessel disease and were successfully revascularized were included in the study. Selected patients had no history of myocardial infarction or heart failure and a normal or near-normal left ventricular ejection fraction (> or =50%) assessed by left ventriculography at admission. Only 58 patients met the inclusion criteria for the study. Out of those, 6 patients refused to participate in the study, and another 5 could not be followed up, so a total of 47 patients were evaluated. Blood samples were taken for measurement of BNP levels at admission, 24 hours later, and 7 days later. Patients were followed up for 1 year. The primary outcome was reduction in left ventricular ejection fraction (LVEF) to <50% after 1 year. Patients who developed echocardiographic signs of reduced systolic function defined as LVEF<50% had significantly higher values of BNP (> or =80 pg/mL) at 24 hours (P=0.001) and 7 days (P=0.020) after STEMI and successful reperfusion. Patients who had BNP levels > or =80 pg/mL after 7 days were 21 times more likely to develop LVEF<50 (odds ratio, 20.8; 95% confidence interval, 2.2-195.2; P=0.008). BNP can be used as a predictor of reduced systolic function in patients with STEMI who underwent successful reperfusion and had normal ejection fraction at admission.