Long-term prognosis of first myocardial infarction according to the electrocardiographic pattern (ST elevation myocardial infarction, non-ST elevation myocardial infarction and non-classified myocardial infarction) and revascularization procedures

The aim of this study was to describe differences in the characteristics and short- and long-term prognoses of patients with first acute myocardial infarction (MI) according to the presence of ST-segment elevation or non-ST-segment elevation. From 2001 and 2003, 2,048 patients with first MI were consecutively admitted to 6 participating Spanish hospitals and categorized as having ST-segment elevation MI (STEMI), non-ST-segment elevation MI (NSTEMI), or unclassified MI (pacemaker or left bundle branch block) according to electrocardiographic results at admission. The proportions of female gender, hypercholesterolemia, hypertension, and diabetes were higher among NSTEMI patients than in the STEMI group. NSTEMI 28-day case fatality was lower (2.99% vs 5.26%, p = 0.02). On multivariate analysis, the odds ratio of 28-day case fatality was 2.23 for STEMI patients compared to NSTEMI patients (95% confidence interval 1.29 to 3.83, p = 0.004). The multivariate adjusted 7-year mortality for 28-day survivors was higher in NSTEMI than in STEMI patients (hazard ratio 1.31, 95% confidence interval 1.02 to 1.68, p = 0.035). However, patients with unclassified MI presented the highest short- and long-term mortality (11.8% and 35.4%, respectively). The excess of short-term mortality in unclassified and STEMI patients was mainly observed in those patients not treated with revascularization procedures. In conclusion, patients with first NSTEMI were older and showed a higher proportion of previous coronary risk factors than STEMI patients. NSTEMI patients had lower 28-day case fatality but a worse 7-year mortality rate than STEMI patients. Unclassified MI presented the worst short- and long-term prognosis. These results support the invasive management of patients with acute coronary syndromes to reduce short-term case fatality.     

Mortality of myocardial infarction

Coronary disease is a major cause of death and disability. From 1975 to 2000, coronary mortality was reduced by half. Better treatments and reduction of risk factors are the main causes. This phenomenon is observed in most developed countries, but mortality from coronary heart disease continues to increase in developing countries. In-hospital mortality of ST elevation myocardial infarction (STEMI) is in the range of 7 to 10% in registries. In infarction without ST segment elevation (NSTEMI), in-hospital mortality is around 5%. More recent studies found a similar in-hospital mortality for STEMI and NSTEMI. Because of patient selection and monitoring, mortality in clinical trials is much lower. After adjustment for the extent of coronary disease, age, risk factors, history of myocardial infarction, the excess mortality observed in women is fading. Many clinical, biological and laboratory parameters are associated with mortality in myocardial infarction. They refer to the immediate risk of death (ventricular rhythm disturbances, shock…), the extent of infarction (number of leads with ST elevation on the ECG, release of biomarkers, ejection fraction…), the presence of heart failure, the failure of reperfusion and the patient's baseline risk (age, renal function…). Risk scores, and more specifically the GRACE risk score, synthesize these different markers to predict the risk of death in a given patient. However, their use for the treatment of myocardial only concerns NSTEMI. Only a limited number of mechanical or pharmacological interventions reduces mortality of heart attack. The main benefits are observed with reperfusion by thrombolysis or primary angioplasty in STEMI, aspirin, heparin, beta-blockers, angiotensin converting enzyme inhibitors. Some medications such as bivalirudin and fondaparinux reduce mortality by decreasing the incidence of hemorrhagic complications. The guidelines classify interventions according to their benefit and especially their ability to reduce mortality. Organized care systems that improve implementation of guidelines also reduce mortality. Finally, some new therapeutic approaches such as post-conditioning and new therapeutic classes offer encouraging prospects for further reducing the mortality of myocardial infarction.     

ST-segment elevation myocardial infarction

Opinion statement ST-segment elevation myocardial infarction (MI) is an emergency medical condition. Expediting the steps leading to coronary reperfusion is of critical importance in improving survival after acute MI. After the diagnosis of acute MI is made, patients should be treated with oxygen, aspirin, nitroglycerin, beta-blockers, heparin, and analgesics, barring any contraindications. If an experienced cardiac catheterization laboratory is available within 60 to 90 minutes, then catheter-based reperfusion therapy is recommended; otherwise, thrombolysis should be considered as an alternate therapy. Therapy with a reduced-dose thrombolytic agent and a glycoprotein IIb/IIIa receptor inhibitor appears to be of an added benefit in establishing TIMI (Thrombolysis in Myocardial Infarction) 3 flow, but this approach awaits final approval prior to widespread use. The adjunctive use of glycoprotein IIb/IIIa receptor inhibitors with percutaneous transluminal coronary angioplasty, with or without stenting, appears to be beneficial and is being used more frequently in the acute setting. Coronary angiography should be performed in patients who fail to respond to thrombolytic therapy or who have evidence of recurrent ischemia. This procedure should not be routinely performed in patients who have responded to thrombolytic therapy. Four to 6 days after an acute MI event, assessment of left ventricular function is recommended. Submaximal exercise test (with or without nuclear or echocardiographic imaging) should be considered in patients prior to discharge from the hospital—an exception can be made in patients with one-vessel disease treated successfully with percutaneous transluminal coronary angioplasty. After discharge, a regular exercise test should be obtained 4 to 6 weeks after an uncomplicated acute MI event. Secondary prevention measures such as weight loss, cessation of smoking, aspirin, beta-blockers, lipid-lowering agents, and angiotensin-converting enzyme inhibitors should be considered in all patients, barring contraindications.     

Infarct-related coronary artery patency and medication use prior to ST-segment elevation myocardial infarction

In patients who have ST-segment elevation myocardial infarction (STEMI), a patent infarct-related artery on the initial angiogram is associated with improved clinical outcomes, including decreased mortality. The present study assessed the influence of administering aspirin, beta blockers, statins, and angiotensin-converting enzyme inhibitors before STEMI on infarct-related artery patency. Our data demonstrate that patients who have STEMI and receive these medications on an outpatient basis before the event have a higher likelihood of having a patent infarct-related artery compared with patients who do not receive these medications. Further, our data demonstrate a graded association according to the number of such medications being administered: the likelihood of a patent infarct-related artery increased to >50% as the number of these medications increased.     

Patient-reported symptoms in acute myocardial infarction: differences related to ST-segment elevation: the MONICA/KORA Myocardial Infarction Registry

Kirchberger I, Meisinger C, Heier M, Kling B, Wende R, Greschik C, von Scheidt W, Kuch B. (Central Hospital of Augsburg, Augsburg; and Institute of Epidemiology, Neuherberg; Germany). Patient‐reported symptoms in acute myocardial infarction: differences related to ST‐segment elevation. J Intern Med 2011; 270 : 58–64. Abstract. Objectives. The early recognition of symptoms of myocardial infarction (MI) is crucial for patients with both ST‐segment elevation (STEMI) and non‐STEMI (NSTEMI). However, to date, only a few studies have examined the differences between patients with STEMI and NSTEMI with regard to the range of presenting MI symptoms. Design. The study population comprised 889 individuals with STEMI and 1268 with NSTEMI, aged 25–74, hospitalized with a first‐time MI between January 2001 and December 2006 recruited from a population‐based MI registry. The occurrence of 13 symptoms was recorded during a standardized patient interview. Results. Patients with STEMI were significantly younger, more likely to be smokers and less likely to have a history of hypertension or sleep disturbances prior to the acute MI (AMI) event than those with NSTEMI. A total of 50% of the patients attributed their experienced symptoms to the heart. Logistic regression modelling revealed that patients with STEMI were significantly more likely than patients with NSTEMI to complain of vomiting [odds ratio (OR) 2.34, 95% confidence interval (CI) 1.76–3.05], dizziness (OR 1.63, 95% CI 1.30–2.03) and diaphoresis (OR 1.49, 95% CI 1.23–1.81). Furthermore, patients with STEMI were less likely to experience dyspnoea (OR 0.81, 95% CI 0.68–0.98) or pain in the throat/jaw (OR 0.80, 95% CI 0.66–0.98). Conclusions. Only half of all patients correctly attributed their symptoms to the heart. Patients with STEMI and NSTEMI showed differences regarding several presenting symptoms. Further research is needed to replicate our results, and public awareness of AMI symptoms needs to be improved.     

Effect of clopidogrel on 1-year mortality in hospital survivors of acute ST-segment elevation myocardial infarction in clinical practice.

AIMS: We sought to assess the effect of clopidogrel on clinical events 1 year after discharge in survivors of ST-elevation myocardial infarction (STEMI) in clinical practice. METHODS AND RESULTS: We analysed data of consecutive survivors of acute STEMI and either concomitant therapy with aspirin or aspirin plus clopidogrel at discharge, who were prospectively enrolled in the Acute Coronary Syndromes (ACOS) registry between July 2000 and November 2002. A total of 5886 (3795 with and 2091 without clopidogrel) patients were included into this analysis. Patients were divided into three groups according to the initial reperfusion therapy: no reperfusion therapy (n=1445), fibrinolysis (n=1734), or primary PCI (n=2707). The multivariable analysis for 12+2 month mortality after discharge using the propenstiy score with adjustment for baseline characteristics and treatments (age, sex, diabetes mellitus, hypertension, prior MI, hyperlipidaemia, renal insufficiency, cardiogenic shock, heart rate, systolic blood pressure, anterior infarct location, reduced left ventricular function, elective revascularization, beta-blockers, statins, ACE-inhibitors) showed that mortality was significantly lower in the aspirin plus clopidogrel group compared with the aspirin group in the total group and patients with reperfusion therapy [total group odds ratio (OR) 0.48, 95% confidence interval (CI) 0.48-0.61; no reperfusion therapy OR 0.96, 95% CI 0.65-1.45; fibrinolysis OR 0.53, 95% CI 0.32-0.87; primary percutaneous coronary intervention OR 0.38, 95% CI 0.23-0.62]. CONCLUSION: In clinical practice, adjunctive therapy with clopidogrel, in addition to aspirin, in survivors after STEMI is associated with a reduction in 1-year mortality in patients treated with early reperfusion therapy.     

Current characteristics and management of ST elevation and non-ST elevation myocardial infarction in the Tokyo metropolitan area: from the Tokyo CCU network registered cohort

Limited data exists on ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) managed by a well-organized cardiac care network in a metropolitan area. We analyzed the Tokyo CCU network database in 2009–2010. Of 4329 acute myocardial infarction (AMI) patients including STEMI (n = 3202) and NSTEMI (n = 1127), percutaneous coronary intervention (PCI) was performed in 88.8 % of STEMI and 70.4 % of NSTEMI patients. Mean onset-to-door and door-to-balloon times in STEMI patients were shorter than those in NSTEMI patients (167 vs 233 and 60 vs 145 min, respectively, p < 0.001). Coronary artery bypass graft surgery was performed in 4.2 % of STEMI and 11.4 % of NSTEMI patients. In-hospital mortality was significantly higher in STEMI patients than NSTEMI patients (7.7 vs 5.1 %, p < 0.007). Independent correlates of in-hospital mortality were advanced age, low blood pressure, and high Killip classification, statin-treated dyslipidemia and PCI within 24 h were favorable predictors for STEMI. High Killip classification, high heart rate, and hemodialysis were significant predictors of in-hospital mortality, whereas statin-treated dyslipidemia was the only favorable predictor for NSTEMI. In conclusion, patients with MI received PCI frequently (83.5 %) and promptly (door-to-balloon time; 66 min), and had favorable in-hospital prognosis (in-hospital mortality; 7.0 %). In addition to traditional predictors of in-hospital death, statin-treated dyslipidemia was a favorable predictor of in-hospital mortality for STEMI and NSTEMI patients, whereas hemodialysis was the strongest predictor for NSTEMI patients.     

Left ventricular assessment in myocardial infarction: the VALIANT registry

BACKGROUND: How often echocardiography and cardiac catheterization are used to evaluate left ventricular (LV) function in patients with myocardial infarction (MI) and how they are associated with quality of care is unknown. METHODS: Patients with MI in the Valsartan in Acute Myocardial Infarction (VALIANT) registry were divided into those with (n = 1423) and without (n = 3968) heart failure (HF), and the use of either echocardiography or cardiac catheterization for LV assessment in each group was compared along with associated baseline characteristics. We evaluated the association between LV assessment and discharge medications. Using a multivariable model with a propensity analysis, we evaluated the association of LV assessment with in-hospital outcomes. RESULTS: Of the patients with HF, 322 (22.6%) had no LV assessment. Patients with HF with LV assessment were discharged more frequently under treatment with aspirin (81.3% vs 70.0%; P<.001), beta-blockers (65.6% vs 56.4%; P = .008), clopidogrel (30.4% vs 14.0%; P<.001), and statins (45.9% vs 34.2%; P<.001). Patients without HF who underwent LV assessment were discharged more frequently under treatment with an angiotensin-converting enzyme inhibitor (53.8% vs 41.5%; P<.001). After adjustment for regional use, other covariates, and revascularization, LV assessment was associated with lower in-hospital mortality in patients with HF (adjusted odds ratio [OR], 0.45; P<.001) and in patients without HF (adjusted OR, 0.30; P<.001). After excluding deaths during the first 2 days, LV assessment remained associated with lower mortality in patients with HF (adjusted OR, 0.59; P = .03) and in patients without HF (adjusted OR, 0.41; P<.001). CONCLUSION: Left ventricular assessment was frequently not performed during the in-hospital stay of patients with acute MI, including those with clinical HF, and its use was associated with better quality of care.     

Impact of medication therapy discontinuation on mortality after myocardial infarction

BACKGROUND: Nonadherence to medications is common, but the determinants and consequences are poorly defined. The objectives of this study were to identify patient and myocardial infarction (MI) treatment factors associated with medication therapy discontinuation and to assess the impact of medication discontinuation 1 month after MI on 12-month mortality. METHODS: This was a multicenter prospective cohort of patients with MI enrolled in the Prospective Registry Evaluating Myocardial Infarction: Event and Recovery study. The outcomes were use of aspirin, beta-blockers, and statins at 1 month after MI hospitalization among patients discharged with all 3 medications as well as 12-month mortality. RESULTS: Of 1521 patients discharged with all 3 medications, 184 discontinued use of all 3 medications, 56 discontinued use of 2 medications, 272 discontinued use of 1 medication, and 1009 continued taking all 3 medications at 1 month. In multivariable analyses, patients not graduating from high school (odds ratio [OR], 1.76; 95% confidence interval [CI], 1.20-2.60) were more likely to discontinue use of all medications. The effect of increasing age on medication therapy discontinuation was greater for females (OR, 1.77; 95% CI, 1.34-2.34) than males (OR, 1.23; 95% CI, 1.02-1.47). Patients who discontinued use of all medications at 1 month had lower 1-year survival (88.5% vs 97.7%; log-rank P<.001) compared with patients who continued to take 1 or more medication(s). In multivariable survival analysis, medication therapy discontinuation was independently associated with higher mortality (hazards ratio, 3.81; 95% CI, 1.88-7.72). Results were consistent when evaluating discontinuation of use of aspirin, beta-blockers, and statins separately. CONCLUSIONS: Medication therapy discontinuation after MI is common and occurs early after discharge. Patients who discontinue taking evidence-based medications are at increased mortality risk. These findings suggest the need to improve the transition of care from the hospital to outpatient setting to ensure that patients continue to take medications that have mortality benefit.     

ST-segment elevation versus non-ST-segment elevation myocardial infarction in current smokers after newer-generation drug-eluting stent implantation

We compared the 2-year major clinical outcomes between ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) in patients who are current smokers who underwent successful percutaneous coronary intervention (PCI) with newer-generation drug-eluting stents (DESs). The availability of data in this regard is limited.A total of 8357 AMI patients were included and divided into 2 groups: the STEMI group (n = 5124) and NSTEMI group (n = 3233). The primary endpoint was the occurrence of major adverse cardiac events (MACE), defined as all-cause death, recurrent myocardial infarction (re-MI), or coronary repeat revascularization. The secondary endpoints were the cumulative incidences of the individual components of MACE and stent thrombosis (definite or probable).After propensity score-matched (PSM) analysis, 2 PSM groups (2250 pairs, C-statistics = 0.795) were generated. In the PSM patients, both for 1 month and at 2 years, the cumulative incidence of MACE (P = .183 and P = .655, respectively), all-cause death, cardiac death, re-MI, all-cause death or MI, any repeat revascularization, and stent thrombosis (P = .998 and P = .341, respectively) was not significantly different between the STEMI and NSTEMI groups. In addition, these results were confirmed using multivariate analysis.In the era of contemporary newer-generation DESs, both during 1 month and at 2 years after index PCI, the major clinical outcomes were not significantly different between the STEMI and NSTEMI groups confined to the patients who are current smokers. However, further research is needed to confirm these results.     

Comparative early and late outcomes after primary percutaneous coronary intervention in ST-segment elevation and non-ST-segment elevation acute myocardial infarction (from the CADILLAC trial)

We determined the outcomes of patients with acute ST-segment elevation (STE) myocardial infarction (STEMI) and non-STEMI (NSTEMI) after primary percutaneous coronary intervention (PCI). The prognosis after primary PCI in STEMI has been extensively studied and defined. Outcomes of patients who undergo primary PCI for NSTEMI are less well established. In total, 2,082 patients with ongoing chest pain for > 30 minutes consistent with acute MI were randomized to balloon angioplasty versus stenting, each with/without abciximab. Of 1,964 patients, STEMI was present in 1,725 (87.8%) and NSTEMI in 239 (12.2%). Compared with STEMI, those with NSTEMI were more likely to have delayed time-to-hospital arrival (2.4 vs 1.8 hours, p = 0.0002) and increased door-to-balloon time (3.2 vs 1.9 hours, p < 0.0001). Patients with NSTEMI were more likely to have Thrombolysis In Myocardial Infarction grade 3 flow at baseline (37.3% vs 19.4%, p < 0.0001) and higher ejection fraction (58.7% vs 55.8%, p = 0.001), but similar rates of postprocedural Thrombolysis In Myocardial Infarction grade 3 flow. At 1 year, patients with NTEMI had similar mortality (3.4% vs 4.4%, p = 0.40) but higher rates of major adverse cardiac events (24.0% vs 16.6%, p = 0.007) that was driven by more frequent ischemic target vessel revascularization (21.8% vs 11.9%, p <0.0001). In conclusion, patients with acute MI without STE who are treated with primary PCI have marked delays to treatment, similar late mortality, and increased rates of ischemic target vessel revascularization compared with patients with STEMI, despite more favorable angiographic features at presentation and similar reperfusion success. The adverse prognosis of patients with NSTEMI should be recognized and efforts made to decrease reperfusion times.     

Feasibility of determining myocardial infarction type from medical record review

BACKGROUND

Hospital discharge data are used extensively in health research. Given the clinical differences between ST segment elevation myocardial infarction (STEMI) and non-ST segment elevation myocardial infarction (NSTEMI), it is important that these entities be distinguishable in a medical record. The authors sought to determine the extent to which the type of MI is recorded in medical records, as well as the consistency of this designation within individual records.

METHODS

Records of all MI patients admitted to a tertiary care centre in Canada from April 1, 2000, to March 31, 2001, were reviewed. Documentation and consistency of the use of the terms STEMI (Q wave, ST elevation or transmural MI) or NSTEMI (non-Q wave, subendocardial or nontransmural MI) were assessed in the admission history, progress notes, coronary care unit summary and discharge summary sections of each record.

RESULTS

Missing data were common; each chart section mentioned MI type in fewer than one-half of charts. When information was combined, it was possible to determine the type of MI in 81.1% of cases. MI type was consistently described as STEMI in 48.7% of cases, and as NSTEMI in 32.4%. Of concern, MI type was discrepant across sections in 10.5% of cases and missing entirely in 8.4% of cases.

CONCLUSIONS

The designation of MI cases as STEMI or NSTEMI is both incomplete and inconsistent in hospital records. This has implications for health services research conducted retrospectively using medical record data, because it is difficult to comprehensively study processes and outcomes of MI care if the type cannot be retrospectively determined.     

Diabetes and myocardial infarction.

Myocardial infarction (MI) is a common cause of mortality in people with diabetes. The case fatality from MI is high and may be reduced by thrombolysis and treatment with aspirin, beta-blockers and angiotensin-converting enzyme inhibitors. Poor metabolic control is common among diabetic patients with MI, but the importance of controlling blood glucose during and following an MI is debatable. Treatment with statins reduces cardiovascular end-points in diabetic patients with previous MI (secondary prevention). Large studies in diabetic patients without existing heart disease have shown statistically insignificant reductions in heart disease and MI with improved glycaemic control of the diabetes (primary prevention). The treatment of hypertension in people with diabetes prevents cardiovascular end-points, and studies on whether the treatment of hyperlipidaemia reduces heart disease and MI are proceeding.     

Angiographic lesion severity and subsequent myocardial infarction

We sought to determine the angiographic severity of coronary lesions leading to ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) with a focus on determining the impact of interval from initial angiogram to subsequent clinical event. In the late 1980s angiographic data on lesion characteristics that culminated in STEMI and NSTEMI were obtained from angiograms obtained several months before MI. It is not clear whether the conclusions on lesion severity would be different if elapsed interval from baseline angiogram to clinical event was factored in the analysis. From 2003 through 2010, we identified 84 patients with NSTEMI and 41 patients with STEMI in vessels without previous intervention. These patients had ≥1 previous angiographic study at our center. Angiograms were reanalyzed with quantitative coronary angiography, and relevant clinical data were obtained from medical records. Similar to previous studies, 71% of patients with STEMI and 63% of patients with NSTEMI had <50% baseline stenosis at the culprit site when the interval from initial angiogram to MI was >3 months. Interestingly, lesions that led to STEMI ≤3 months after evaluation were more severe than those leading to STEMI in >3 months (59 ± 31% vs 36 ± 21%, p = 0.02) with 57% of lesions having >50% stenosis. Although most MIs occurred at sites that did not have significant obstruction when examined >3 months before MI, most baseline lesions showed significant luminal narrowing when examined ≤3 months before STEMI. In conclusion, high-grade coronary stenosis may be an important predictor of STEMI in subsequent months.     

Impact of acute beta-blocker therapy for patients with non-ST-segment elevation myocardial infarction

Purpose

Early use of beta-blockers is a quality indicator for the treatment of patients with non-ST-segment elevation myocardial infarction (NSTEMI), despite limited data from randomized clinical trials in this population. We sought to determine the impact of acute beta-blocker therapy on outcomes in patients with NSTEMI.

Subjects and Methods

We examined acute (<24 hours) beta-blocker use in 72,054 patients with NSTEMI from the Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes with Early Implementation of the American College of Cardiology/American Heart Association Guidelines (CRUSADE) initiative at 509 US hospitals from 2001-2004. We analyzed patient and provider factors associated with beta-blocker use and the impact of beta-blocker therapy on unadjusted, risk-adjusted, and propensity matched outcomes in the overall sample and among selected high-risk subgroups.

Results

A total of 82.5% of patients without documented contraindications received acute beta-blocker therapy. Factors strongly associated with acute beta-blocker use included prior beta-blocker use, higher presenting systolic blood pressure, lower heart rate, lack of signs of heart failure, and cardiology care. Acute beta-blocker use was associated with lower in-hospital mortality (unadjusted 3.9% vs 6.9%, P <.001, adjusted odds ratio 0.66, 95% confidence interval 0.60-0.72), lower adjusted mortality among most of 6 subgroups determined by propensity to receive acute beta-blockers, and lower adjusted mortality in patients with and without signs of heart failure and in those <80 years and those ≥80 years old.

Conclusions

The majority of NSTEMI patients receive acute beta-blocker therapy. Certain patient subgroups remain undertreated. Because treatment with acute beta-blockers was associated with improved clinical outcomes in nearly all patient subgroups assessed, broader use in patients with NSTEMI appears warranted.     

Measurement of microvascular function in patients presenting with thrombolysis for ST elevation myocardial infarction,and PCI for non-ST elevation myocardial infarction

BackgroundIn this prospective study, we compared the invasive measures of microvascular function in two subsets: patients with pharmacoinvasive thrombolysis for STEMI, and patients undergoing percutaneous coronary intervention (PCI) for NSTEMI.MethodsThe study consisted of 17 patients with STEMI referred for cardiac catheterisation post thrombolysis, and 20 patients with NSTEMI. Coronary physiological indexes were measured in each patient before and after PCI.ResultsThe median pre-PCI index of microcirculatory function (IMR) at baseline was significantly higher in the STEMI group than the NSTEMI group (26 units vs. 15 units, p = 0.02). Following PCI, IMR decreased in both groups (STEMI 20 units vs. NSTEMI 14 units, p = 0.10). There was an inverse correlation between post PCI IMR and left ventricular ejection fraction (LVEF) (r = −0.52, p = 0.001). Furthermore, post PCI IMR was an independent predictor of index admission LVEF in the total population (β = −0.388, p = 0.02).ConclusionInvasive measures of microvascular function are inferior in a pharmacoinvasive STEMI group compared to a clinically stable NSTEMI group. In the STEMI population, the IMR following coronary intervention appears to predict LVEF.     

ST deviation pattern in acute myocardial infarction is not related to lesion location

Background In ST-elevation MI (STEMI) the culprit artery is usually occluded, whereas non-STEMI (NSTEMI) it is usually patent. The location of the ruptured plaque may influence MI type. We examine whether the distance from the coronary ostium to the culprit lesion is different in STEMI as compared to NSTEMI. Methods We selected patients who presented with an acute MI and underwent coronary angiography during hospitalization. The analysis included 754 patients of whom 514 had STEMI and 240 had NSTEMI. The distance from the coronary ostium to the site of thrombosis was measured. Results For both STEMI and NSTEMI patients the first 60 mm of the coronary artery contained 75% of the culprit lesions. There were no significant differences in median distances from the vessel ostium to the site of thrombosis as well. Conclusions The distance from coronary ostium to culprit lesion is similar in STEMI and NSTEMI. Culprit lesion location does not appear to influence the development of STEMI as opposed to NSTEMI.     

Effect of prior stroke on the use of evidence-based therapies and in-hospital outcomes in patients with myocardial infarction (from the NCDR ACTION GWTG registry)

Patients with previous stroke are at high-risk for myocardial infarction (MI). Concern regarding increased risk of bleeding or recurrent stroke in this patient population might alter therapeutic decisions. Data were collected from 281 hospitals in the United States in the NCDR ACTION Registry. Patients with ST-segment elevation MI (STEMI; n = 15,997) or non-STEMI (NSTEMI; n = 25,514) entered into the registry from January 1, 2007 through December 31, 2007 were included. We assessed use of evidence-based medications and procedures in patients with and without previous stroke. Risk-adjusted odds ratio of death, major bleeding not related to coronary artery bypass grafting, and a composite outcome (major adverse cardiac events [MACEs], i.e., death/MI/stroke/cardiogenic shock/congestive heart failure) were calculated using logistic regression. Previous stroke was reported in 5.1% of patients with STEMI and 9.3% of those with NSTEMI. Of patients with STEMI eligible for reperfusion therapy, those with previous stroke were less likely to receive reperfusion therapy compared to patients without previous stroke. Patients with previous stroke had longer door-to-needle and door-to-balloon times. Of patients with STEMI and NSTEMI, those with previous stroke were less likely to receive evidence-based therapies. Death, MACEs, and major bleeding were more common with previous stroke. When adjusted for baseline risk, patients with previous stroke were at increased risk of death (only those with STEMI) and MACEs but not bleeding. In conclusion, patients with STEMI and previous stroke are at increased risk for death and patients with STEMI and NSTEMI are at increased risk of MACE. Despite this, previous stroke patients are less likely to receive guideline-based MI therapies.     

Acute treatment of myocardial infarction in Canada 1999-2002

BACKGROUND: Therapy for management of acute myocardial infarction (AMI) varies according to patient, prescriber and geographical characteristics. OBJECTIVES: To describe the in-hospital use of reperfusion therapy for ST elevation MI (STEMI) and discharge use of acetylsalicylic acid, beta-blockers, angiotensin-converting enzyme inhibitors (ACEIs) and statins in patients presenting with either STEMI or non-STEMI in Canada from 1999 to 2002. METHODS: Four Canadian registries (FASTRAK II, Canadian Acute Coronary Syndromes, Enhanced Feedback for Effective Cardiac Treatment and Improving Cardiovascular Outcomes in Nova Scotia) were used to identify patients with AMI in Canada and to measure in-hospital reperfusion and medication use. Use rates were compared by age, sex, time period and geographical area, according to available data. RESULTS: Use rates for reperfusion in STEMI patients ranged from 60% to 70%, primarily representing fibrinolytic therapy. A delay in presentation to hospital after symptom onset represented an impediment to timely therapy, which was particularly pronounced for women and elderly patients. Overall, less than 50% of patients met the door-to-needle target of less than 30 min. Medication use rates at discharge increased from 1999/2000 to 2000/2001 across the different data sources: acetylsalicylic acid, 83% to 88%; beta-blockers, 74% to 89%; ACEIs, 54% to 67%; statins, 41% to 53%; and calcium antagonists, 21% to 32%. CONCLUSIONS: Canadian and provincial rates of use of evidence-based medications for the treatment of AMI have increased over time, although there remains room for improvement. A single, comprehensive data source would supply better insights into the management of AMI in Canada.