Onset Of Myocardial Infarction Symptoms Research Articles

Growth differentiation factor-15 — a new indicator of unfavorable prognosis in uncomplicated myocardial infarction

Aim. To evaluate the role of growth differentiation factor-15 (GDF-15) in long-term prognosis in patients with uncomplicated myocardial infarction (MI).Material and methods. The study included 118 patients with uncomplicated ST-elevation and non-ST-elevation MI. In addition to the routine examination, all patients were analyzed for GDF-15, as well as the N-terminal pro-brain natriuretic peptide (NT-proBNP) by enzyme immunoassay in the first 48 hours from the onset of MI symptoms. The changes in the patients' condition were assessed by questioning after 1, 3, 6, 12 months, as well as the analysis of medical records in the event of repeated cardiovascular events and deaths. The endpoints were cardiovascular death, hospitalization for recurrent MI, and/or unstable angina. To assess the value of quantitative variables in predicting recurrent cardiovascular events, the ROC analysis was used. The survival function of patients was assessed using the Kaplan-Meier method.Results. Twelve-month follow-up revealed 29 recurrent cardiovascular events, including 2 deaths and 8 recurrent MIs. GDF-15 was predictive of recurrent cardiovascular events with a sensitivity of 77,3% and a specificity of 56,2% (ROCAUC, 0,7±0,065 (95% confidence interval (CI), 0,572-0,827), p=0,004). Patients with GDF-15 ≥2,075 ng/mL had a higher risk of recurrent cardiovascular events (hazard ratio (HR), 3,4 (95% CI, 1,342-8,613), p=0,005). Another prognostic factor influencing the rate of recurrent cardiovascular events was NT-proBNP. An NTproBNP level ≥578 pg/mL was associated with an increased risk of cardiovascular death and rehospitalization for unstable angina and recurrent MI (HR, 4,3 (95% CI 1,828-10,239), p=0,00019).Conclusion. The combined increase in GDF-15 ≥2,075 ng/mL and NT-proBNP ≥578 pg/mL in patients with uncomplicated MI increases the risk of recurrent cardiovascular events over the next 12 months (HR, 4,5 (95% CI, 2,087-9,736), p=0,00018).

Optimal reperfusion time in patients with non-ST elevation acute myocardial infarction and low ischemic risk

The aim of the study was to identify the optimal time window for performing effective percutaneous coronary reperfusion in patients with non-ST-segment elevation acute myocardial infarction (NSTEMI) who are part of the low ischemic risk group. 252 patients with NSTEMI and low ischemic risk who underwent coronary angioplasty up to 30 days after the onset of the infarction were evaluated the second day post-procedurally and at a distance of 6 months. The general group was randomized depending on the echocardiographic evolution. 131 patients with unfavorable evolution and 121 with more complete restoration of left ventricular contractile function. The time windows from the onset of myocardial infarction symptoms in which percutaneous myocardial reperfusion was applied were studied. Following the study, the time interval of 73 hours -14 days proved to be optimal in which a more favorable clinical and echocardiographic evolution is ensured.

Predictors of anticipated coping behavior at myocardial infarction symptom onset among a nationwide sample of Korean adults.

OBJECTIVESThis cross-sectional study based on the health belief model investigated predictors of anticipated coping behavior at myocardial infarction (MI) symptom onset using secondary data from the 2017 Korea Community Health Survey.METHODSModifying variables (socioeconomic, health knowledge, perceived threat) were selected as independent variables and anticipated coping behavior at MI symptom onset as the dependent variable. Calling 911 was classified as the correct anticipated coping behavior, while visiting a hospital or an oriental hospital, calling family, and others were classified as incorrect.RESULTSOf 227,740 participants, 83.2% reported correct anticipated coping behaviors. The likelihood of calling 911 was low if participants experienced atypical symptoms (jaw, neck, back, arm, and shoulder pain), even if they were aware of those symptoms. However, 69.9% of participants who were aware of typical symptoms (chest pain) stated that they would call-911. Sex, age, hypertension, dyslipidemia, obesity, and awareness of MI symptoms affected the correct anticipated coping behavior.CONCLUSIONSCorrect coping abilities among the general public are vitally important for early treatment of MI patients and reduction of hospitalization time. Members of the general public in their 20s and 30s, 60 years of age or older, with cardiovascular risk factors (male sex, hypertension, dyslipidemia, and obesity), and who are not aware of MI symptoms should be educated about the typical and atypical symptoms of MI. Emergency medical services should be called without delay if needed, and public relations activities should be carried out to raise awareness that anyone can use emergency medical services.

Statin Use in the Early Phase of ST-Segment Elevation Myocardial Infarction Is Associated With Decreased QTc Dispersion.

Although there is strong evidence supporting the use of statin therapy after myocardial infarction (MI), some mechanistic gaps exist regarding the benefits of this therapy at the very onset of MI. Among the potential beneficial mechanisms, statins may improve myocardial electrical stability and reduce life-threatening ventricular arrhythmia, as reported in stable clinical conditions. This study was designed to evaluate whether this mechanism could also occur during the acute phase of MI. Consecutive patients with ST-segment elevation MI were treated without statin (n = 57) or with a simvastatin dose of 20 to 80 mg (n = 87) within the first 24 hours after MI symptom onset. Patients underwent digital electrocardiography within the first 24 hours and at the third and fifth days after MI. The QTC dispersion (QTcD) was measured both with and without the U waves. Although QTcD values were equivalent between the groups at the first day (80.6 ± 36.0 vs 80.0 ± 32.1; P = 0.36), they were shorter among individuals using simvastatin than in those receiving no statins on the third (90.4 ± 38.6 vs 86.5 ± 36.9; P = .036) and fifth days (73.1 ± 31 vs 69.2 ± 32.6; P = .049). We obtained similar results when analyzing the QTcD duration including the U wave. All values were adjusted by an ANCOVA model after propensity-score matching. Statins administered within 24 hours of ST-segment elevation MI reduced QTc dispersion, which may potentially attenuate the substrate for life-threatening ventricular arrhythmias.

Risk of myocardial infarction immediately after alcohol consumption.

Habitual moderate alcohol consumption is associated with a lower risk of acute myocardial infarction (MI), whereas heavy (binge) drinking is associated with higher cardiovascular risk. However, less is known about the immediate effects of alcohol consumption on the risk of acute MI and whether any association differs by beverage type or usual drinking patterns. We conducted a case-crossover analysis of 3869 participants from the Determinants of Myocardial Infarction Onset Study who were interviewed during hospitalization for acute MI in one of the 64 medical centers across the United States in 1989-1996. We compared the observed number of times that each participant consumed wine, beer, or liquor in the hour preceding MI symptom onset with the expected frequency based on each participant's control information, defined as the number of times the participant consumed alcohol in the past year. Among 3869 participants, 2119 (55%) reported alcohol consumption in the past year, including 76 within 1 hour before acute MI onset. The incidence rate of acute MI onset was elevated 1.72-fold (95% confidence interval [CI] = 1.37-2.16) within 1 hour after alcohol consumption. The association was stronger for liquor than for beer or wine. The higher rate was not apparent for daily drinkers. For the 24 hours after consumption, there was a 14% lower rate (relative risk = 0.86 [95% CI = 0.79-0.95]) of MI compared with periods with no alcohol consumption. Alcohol consumption is associated with an acutely higher risk of MI in the subsequent hour among people who do not typically drink alcohol daily.

Triggering of acute coronary occlusion by episodes of anger.

The aim of this study was to report the association between episodes of anger and acute myocardial infarction (MI) in patients with angiographically confirmed coronary occlusion. 313 participants with acute coronary occlusion (Thrombolysis In Myocardial Infarction 0 or 1 at emergency angiography) reported frequency of anger episodes in the 48 h prior to MI. In primary analysis, anger exposures within 2 h and 2-4 h prior to symptom onset were compared with subjects' own usual yearly exposure to anger using case-crossover methodology. Anger level ≥5 (on an anger scale of 1-7) was reported by seven (2.2%) participants within 2 h of MI. Compared with usual frequency, the relative risk of onset of MI symptoms occurring within 2 h of anger level ≥5 (defined as very angry) was 8.5 (95% confidence interval 4.1-17.6). Anger level <5 was not associated with onset of MI symptoms. Compared with 24-26 h pre MI, anxiety scores >75th percentile on State-Trait Personality Inventory were associated with a relative risk of 2.0 (95% confidence interval 1.1-3.8) and in those above the 90th percentile, the relative risk of MI symptom onset was 9.5 (95% confidence interval 2.2-40.8). Findings confirm that episodes of intense anger, defined as being 'very angry, body tense, clenching fists or teeth' (within 2 h) are associated with increased relative risk for acute coronary occlusion. Additionally, increased anxiety was associated with coronary occlusion. Further study, including the role of potential modifiers, may provide insight into prevention of MI during acute emotional episodes.

ATRIAL FIBRILLATION ASSOCIATED WITH MYOCARDIAL INFARCTION OF DIFFERENT LOCALIZATIONS

Aim. To specify the mechanism of atrial fibrillation (AF) development and to evaluate the function of left atrium after restoration of sinus rhythm in patients with AF and acute myocardial infarction (MI) without significant reduction in left ventricular systolic function. Material and methods. 52 patients with MI were enrolled into the study and divided into 2 groups. The first group included 29 patients with inferior MI, the second one – 23 patients with anterior MI. All patients underwent percutaneous intervention within first 24 hours after the onset of MI symptoms. Time and triggering factors of AF symptoms onset, its duration, the size of the heart chambers and time of left atrium function recovery were evaluated. Results. In patients with anterior MI AF developed later than in those with inferior MI (on day 2 in 12 patients and on day 3 – in 11 patients with anterior MI versus on day 1 in 25 patients and on day 2 – in 4 patients with inferior MI, p&lt;0.05). Besides, in case of inferior MI the AF paroxysms were less persistent. The average duration in the first and second groups was 5.3±4.8 vs 42.3±12.1 hours, respectively; p&lt;0.0001. There were also differences in the triggering factors of AF paroxysms. So, only 5 patients with inferior MI had congestive heart failure class KIllip II or higher, while in the second group it was present in 20 patients; p&lt;0.0001. AF paroxysms in patients with anterior MI were accompanied by severe hemodynamic disorders and significantly worsened the prognosis. The assessment of left atrium function showed that it’s often not impaired in inferior MI after sinus rhythm restoration (we observed normal peak A on the Doppler transmitral flow image in 25 patients). In case of anterior MI the effective atrial systole was absent for at least 7 days in 13 patients; p&lt;0.005. Conclusion. AF has less favorable course in anterior MI. In this category of patients AF paroxysms are followed by hemodynamic disorders, and after the restoration of sinus rhythm the majority of patients has consistently impaired mechanical function of the left atrium, which is related to an increased risk of thromboembolic complications.

The impact of successful manual thrombus aspiration on in-stent restenosis after primary PCI

This study sought to investigate the impact of successful manual thrombus aspiration on angiographic in-stent restenosis and clinical outcome in patients treated by bare metal stent implantation for ST-segment elevation acute myocardial infarction. There are very limited data on the impact of manual thrombus aspiration on the occurrence of in-stent restenosis after bare metal stent implantation. This was a prospective, randomized, single-center study. Patients (N=60) presenting within 12 h of ST-segment elevation acute myocardial infarction symptom onset were randomized to primary percutaneous coronary intervention (PCI) with (N=30) or without (N=30) upfront manual thrombus aspiration using the Export aspiration catheter. All patients underwent control coronary angiography after 6 months. Baseline, clinical, and angiographic preprocedural findings did not differ between the two groups. Patients who underwent successful manual thrombus aspiration had significantly higher minimal lumen diameter after 6 months (2.25±0.90 vs. 1.63±0.76, P=0.005), significantly lower percentage diameter stenosis (28.81 vs. 45.03%, P=0.017), and significantly lower late lumen loss (0.73±0.84 vs. 1.18±0.79, P=0.035). There was a trend for lower rate of major adverse cardiocerebrovascular events such as death, myocardial reinfarction, stroke, and target lesion revascularization in the same group of patients (16.67 vs. 26.67%, P=0.347). Successful upfront manual thrombus aspiration during primary PCI showed beneficial effects on the reduction of in-stent restenosis after bare metal stent implantation compared with standard PCI.

Risk of Acute Myocardial Infarction After the Death of a Significant Person in One's Life

Background— Acute psychological stress is associated with an abrupt increase in the risk of cardiovascular events. Intense grief in the days after the death of a significant person may trigger the onset of acute myocardial infarction (MI), but this relationship has not been systematically studied. Methods and Results— We conducted a case-crossover analysis of 1985 participants from the multicenter Determinants of Myocardial Infarction Onset Study interviewed during index hospitalization for an acute MI between 1989 and 1994. We compared the observed number of deaths in the days preceding MI symptom onset with its expected frequency based on each patient's control information, defined as the occurrence of deaths in the period from 1 to 6 months before infarction. Among the 1985 subjects, 270 (13.6%) experienced the loss of a significant person in the prior 6 months, including 19 within 1 day of their MI. The incidence rate of acute MI onset was elevated 21.1-fold (95% confidence interval, 13.1–34.1) within 24 hours of the death of a significant person and declined steadily on each subsequent day. The absolute risk of MI within 1 week of the death of a significant person is 1 excess MI per 1394 exposed individuals at low (5%) 10-year MI risk and 1 per 320 among individuals at high (20%) 10-year risk. Conclusions— Grief over the death of a significant person was associated with an acutely increased risk of MI in the subsequent days. The impact may be greatest among individuals at high cardiovascular risk.

Circulating microRNAs are new and sensitive biomarkers of myocardial infarction

AimsCirculating microRNAs (miRNAs) may represent a novel class of biomarkers; therefore, we examined whether acute myocardial infarction (MI) modulates miRNAs plasma levels in humans and mice.Methods and resultsHealthy donors (n = 17) and patients (n = 33) with acute ST-segment elevation MI (STEMI) were evaluated. In one cohort (n = 25), the first plasma sample was obtained 517 ± 309 min after the onset of MI symptoms and after coronary reperfusion with percutaneous coronary intervention (PCI); miR-1, -133a, -133b, and -499-5p were ∼15- to 140-fold control, whereas miR-122 and -375 were ∼87–90% lower than control; 5 days later, miR-1, -133a, -133b, -499-5p, and -375 were back to baseline, whereas miR-122 remained lower than control through Day 30. In additional patients (n = 8; four treated with thrombolysis and four with PCI), miRNAs and troponin I (TnI) were quantified simultaneously starting 156 ± 72 min after the onset of symptoms and at different times thereafter. Peak miR-1, -133a, and -133b expression and TnI level occurred at a similar time, whereas miR-499-5p exhibited a slower time course. In mice, miRNAs plasma levels and TnI were measured 15 min after coronary ligation and at different times thereafter. The behaviour of miR-1, -133a, -133b, and -499-5p was similar to STEMI patients; further, reciprocal changes in the expression levels of these miRNAs were found in cardiac tissue 3–6 h after coronary ligation. In contrast, miR-122 and -375 exhibited minor changes and no significant modulation. In mice with acute hind-limb ischaemia, there was no increase in the plasma level of the above miRNAs.ConclusionAcute MI up-regulated miR-1, -133a, -133b, and -499-5p plasma levels, both in humans and mice, whereas miR-122 and -375 were lower than control only in STEMI patients. These miRNAs represent novel biomarkers of cardiac damage.

PROGNOSTIC VALUE OF PATHOLOGIC Q-WAVE AND TIME OF ITS APPEARANCE IN PATIENTS WITH MYOCARDIAL INFARCTION: COMPARISON STUDY

Aim. To evaluate short- and long-term prognosis of myocardial infarction (MI) depending on occurrence of pathologic Q-wave on ECG and time of its appearance. Material and methods. 616 patients with initial ST-elevated MI were included into the study — 254 women and 362 men, aged 62.1±11.2. All patients were split up three groups depending on occurrence of pathologic Q-wave on ECG and time of its appearance. First group consisted of 311 patients with early Q-wave (during first 6 hours from onset of MI symptoms). Second group consisted of 120 patients with late Q-wave (from 6 to 24 hours from onset of MI symptoms). Third group consisted of 185 patients with non-Q-wave MI. Results. The hospital lethality in the patients with early Q-wave was significantly higher than this in patients of the second and the third groups. However, we didn’t reveal significant differences between patients with late Q-wave and patients without Q-wave on ECG. The incidences of cardiac death (sudden death and fatal MI), non-fatal MI and hospitalization because of unstable angina was assessed during next two years. During the follow-up period patients of three groups had similar incidences of the non-fatal MI and hospitalization because of unstable angina. However, incidence of cardiac death was significantly higher in early Q-wave group in comparison with non-Q-wave group. Conclusion. Occurrence of pathologic Q-wave on ECG and time of its appearance should be taken into account to assessed short- and long-term prognosis of MI.

Abstract 5019: Circulating MicroRNAs as New Biomarkers of Myocardial Infarction in Man

Background and objective: microRNAs (miRs) are small non-coding RNAs that regulate translation of messenger RNAs (mRNA) into proteins. Recently, it has been suggested that circulating miR may represent a novel class of biomarkers in cancer and liver disease, however no data are available in cardiovascular diseases. Our objective was to examine miR plasma levels in humans and mice with acute myocardial infarction (MI). Results: We analyzed the expression of 365 human miRs in plasma from healthy donors (n=9) and patients (n=11) with acute MI and ST-segment elevation (STEMI). In STEMI patients, during the initial 1 to 7 hours after the onset of MI symptoms, miR 1, 133a, 133b and 499 plasma levels increased over 10–190-folds (p&lt;0.05) and at day 5 they were back to control values; in contrast, miR 122 and miR 375, at day 0 exhibited a 60 and 80 % decrease, respectively, and at day 30 they were still 50% lower than control (p&lt;0.05). In 4 additional MI patients miR plasma levels were measured simultaneously and in the same blood samples with total CPK and TnI, at frequent intervals after reaching the hospital. All patients were reperfused within 4 hours after admission to the hospital. Both CPK and TnI had their peak expression 6 hours after reaching the hospital; in contrast miR 1, 133a and 133b peak increase was achieved within 3h whereas miR 499 peak occurred at 12 hours. Additional studies were performed in a mouse model of MI and miR plasma levels were measured at a single time point, i.e. 3 hr after coronary artery occlusion. Experiments in sham operated control (n=4) and MI (n=9) mice showed that circulating miR 1, 133a, 133b and 499 increased 10–18 folds (p&lt; 0.01); this miR signature closely mimicked the results in humans. Conclusions: miR 1, 133a, 133b and 499 plasma levels are strongly upregulated after MI and may represent novel and sensitive biomarkers of cardiac damage. The negative regulation of miR 122 and 375 observed in humans raises the possibility that in man, during severe cardiac ischemia, miR release from cardiac cells may be due also to the modulation of active transport mechanisms and not only to cardiac necrosis.

Causes of death in patients with acute myocardial infarction treated with angiotensin-converting enzyme inhibitors: Findings from the Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto (GISSI)–3 trial

The causes of death occurring in clinical trials of myocardial infarction (MI) are scarcely reported in the literature. The present analysis is aimed to describe the inhospital causes of death in patients with acute MI stratified to angiotensin converting enzyme (ACE) inhibitor treatment/no treatment, as described in the GISSI-3 trial. Furthermore, the 5-year survival analysis of GISSI-3 patients is reported. An independent committee assigned the definition of causes of death of GISSI-3 based on clinical and/or anatomical data. Univariate and multivariable analyses were performed to identify the predictors of early and late deaths. Kaplan-Meier mortality curves were used to describe the effects of ACE-I treatment on mortality on a median follow-up period of 56 months. Patients receiving lisinopril had fewer inhospital cardiac deaths than patients allocated to the no-lisinopril group (4.7% vs 5.3%, P = .052), corresponding to a 12% relative risk reduction. The risk of dying from cardiac rupture was reduced by 39% by lisinopril treatment. The improvement in survival associated with the lisinopril treatment was mainly due to a reduction in cardiac rupture, electromechanical dissociation, and pump failure occurring early (within 4 days) from the onset of MI symptoms. The beneficial effects of lisinopril observed at 6 weeks (8 fewer deaths per 1000 treated patients) were maintained up to nearly 5 years (10 fewer deaths per 1000). Early administration of ACE inhibitors in unselected patients with acute MI should be considered standard therapy to reduce early deaths, specifically those due to cardiac rupture. The early beneficial effect persisted up to nearly 5 years.

Exposure to Traffic and Cardiovascular Disease

MS7-12 Abstract: The impact of traffic exposures based on questionnaire data and myocardial infarction (MI) onset was assessed earlier (N Engl J Med. 2004;351:1721–1730). The purpose of this presentation is to describe an analysis of diary data over the extended time period from February 1999 to December 2003. Hospitalized MI survivors age 25 to 74 years are routinely registered in the study area. Activities of the patients on the day of the MI and during the 3 days before the MI were recorded in a standardized, interview-based diary, including sleeping periods, activity levels during the day, times spent outdoors, means of transportation used, location within the study area, angina pectoris symptoms, occurrence of extreme anger or joy, and exposure to dust or solvents. Conditional logistic regression models were used to assess the association between transient individual level traffic exposures and MI. One-hour periods in the 0 to 6 hours before MI onset were selected as case periods. Each case period was matched with 1-hour periods 24, 48, and 72 hours before the case period. In a second approach, control exposures were defined as exposure of the same case 24 to 71 hours before MI onset. Over the 6-year period, 1454 patients with MI provided activity data in the hours before MI symptom onset and in at least one control period. Exposure to traffic was associated with an odds ratio (OR) of 3.20 (95% confidence interval [CI]: 2.46–4.14) when 3 control periods spaced 24 hours apart were considered. The results were consistently estimated for the time period from February 1999 to July 2001 (OR: 3.16, 95% CI: 2.19–4.54) and from August 2001 to December 2003 (OR: 3.25, 95% CI: 2.26–4.67). When considering all controls available, the OR was 3.09 with 95% CI from 2.59 to 3.68 confirming the results published earlier. The data presented here might indicate that high exposures to freshly emitted exhaust particles during these time periods might in part contribute to the risk of MI onset. Further investigations are needed to identify the risk factors associated with times spent in traffic to reduce the risk in potentially vulnerable subpopulations.

Circadian variation in the onset of myocardial infarction: effect of duration of diabetes.

There are conflicting reports regarding circadian variation in the onset of acute myocardial infarction (MI) among patients with diabetes. We therefore, studied the circadian pattern of the incidence of acute MI in patients (n = 3,882) who were enrolled in the Onset Study stratified by the presence, type, and duration of diabetes. The Onset Study was conducted at 64 U.S. medical centers between August 1989 and September 1996. We used harmonic regression model to evaluate the circadian variation of MI symptom onset in patients with and without diabetes. Subgroup analysis was performed according to the presence, type, and duration of diabetes by the chi(2) test (dividing the day into four 6-h intervals). Patients without diabetes exhibited a prominent morning peak in the incidence of acute MI symptom onset (P < 0.001). In contrast, patients with type 1 diabetes and type 2 diabetes > or =5 years had a marked attenuation of the morning peak. Patients who had type 2 diabetes diagnosed within the previous 5 years had a pattern of onset of acute MI similar to patients without diabetes. Patients with type 1 diabetes and those with type 2 diabetes > or =5 years have an attenuation of the morning peak in acute MI. Inconsistency in observation of such an effect in patients with diabetes in the past may well have been due to difference in the duration of diabetes and thus the variable extent of underlying autonomic dysfunction.

Decrease in Acute Myocardial Infarction Symptom Onset to Emergency Department Arrival Time Following a Community Outreach Program

Decrease in Acute Myocardial Infarction Symptom Onset to Emergency Department Arrival Time Following a Community Outreach Program

Implications of the timing of onset of cardiogenic shock after acute myocardial infarction: a report from the SHOCK Trial Registry

OBJECTIVESWe sought to examine the implications of the timing of onset of cardiogenic shock (CS) after acute myocardial infarction (MI).BACKGROUNDLittle information is available about the relationships between timing, clinical substrate, management and outcomes of shock.METHODSThe multinational SHOCK Trial Registry enrolled MI patients with CS from 1993 to 1997. Cardiogenic shock was predominantly attributable to left ventricular (LV) failure in 815 Registry patients for whom temporal data were available. We examined factors related to the timing of shock onset and the relation of temporal onset to in-hospital outcomes.RESULTSOverall, shock developed a median of 6.2 h after MI symptom onset. Shock onset varied by culprit artery: left main, median 1.7 h; right, 3.5 h; circumflex, 3.9 h; left anterior descending (LAD), 11.0 h; saphenous vein graft, 10.9 h (p = 0.025). Early shock (<24 h) occurred in 74.1% and was associated with chest pain at shock onset, ST-segment elevation in two or more leads, multiple infarct locations, inferior MI, left main disease and smoking. Late shock (≥24 h) was associated with recurrent ischemia, Q waves in two or more leads and LAD culprit vessel. Mortality was higher in patients with early versus late shock (62.6% vs. 53.6%, p = 0.022).CONCLUSIONSShock onset after acute MI occurred within 24 h in 74% of the patients with predominant LV failure. Mortality was slightly higher in patients developing shock early rather than later. Many factors influence when shock develops, which has implications for its management.

Relationship of symptom-onset-to-balloon time and door-to-balloon time with mortality in patients undergoing angioplasty for acute myocardial infarction.

Rapid time to treatment with thrombolytic therapy is associated with lower mortality in patients with acute myocardial infarction (MI). However, data on time to primary angioplasty and its relationship to mortality are inconclusive. To test the hypothesis that more rapid time to reperfusion results in lower mortality in the strategy of primary angioplasty. Prospective observational study of data collected from the Second National Registry of Myocardial Infarction between June 1994 and March 1998. A total of 661 community and tertiary care hospitals in the United States. A cohort of 27,080 consecutive patients with acute MI associated with ST-segment elevation or left bundle-branch block who were treated with primary angioplasty. In-hospital mortality, compared by time from acute MI symptom onset to first balloon inflation and by time from hospital arrival to first balloon inflation (door-to-balloon time). Using a multivariate logistic regression model, the adjusted odds of in-hospital mortality did not increase significantly with increasing delay from MI symptom onset to first balloon inflation. However, for door-to-balloon time (median time 1 hour 56 minutes), the adjusted odds of mortality were significantly increased by 41% to 62% for patients with door-to-balloon times longer than 2 hours (for 121-150 minutes: odds ratio [OR], 1.41; 95% confidence interval [CI], 1.08-1.84; P=.01; for 151-180 minutes: OR, 1.62; 95% CI, 1.23-2.14; P<.001; and for >180 minutes: OR, 1.61; 95% CI, 1.25-2.08; P<.001). The relationship in our study between increased mortality and delay in door-to-balloon time longer than 2 hours (present in nearly 50% of this cohort) suggests that physicians and health care systems should work to minimize door-to-balloon times and that door-to-balloon time should be considered when choosing a reperfusion strategy. Door-to-balloon time also appears to be a valid quality-of-care indicator. JAMA. 2000.

Long-term effects on left ventricular function after late thrombolysis in patients with myocardial infarction

This open-label, uncontrolled, retrospective study assessed the long-term effects of late thrombolysis on left ventricular (LV) function. We studied 79 patients (52 men and 27 women; mean age, 51 ± 5 years) treated with alteplase (group 1) and 46 patients (33 men and 13 women; mean age, 52 ± 8 years) treated with heparin alone (group 2) at their first myocardial infarction (MI). Patients were eligible for the study if they were younger than 62 years, their duration of pain was longer than 6 hours, and they had no episodes of angina in the 48 hours preceding their MI. The peak of creatine kinase-muscle and brain subunits was significantly less in group 1 than group 2 (106 ± 67 vs 205 ± 102 IU/L). Both LV ejection fraction and wall-motion score were better in thrombolysed patients, and the cumulative frequency of radionuclide defects was higher in these patients during the 4-year follow-up. Our study supports the concept that thrombolysis reduces the incidence of long-term post-MI residual ischemia, improving global LV function even when given late after the onset of MI symptoms.

The Prehospital Electrocardiogram in Acute Myocardial Infarction: Is Its Full Potential Being Realized?

Objectives. This study sought to examine the management and subsequent outcomes of patients with a prehospital electrocardiogram (ECG) in a large, voluntary registry of myocardial infarction.Background. The prehospital ECG has been proposed as a means of rapidly identifying patients with acute myocardial infarction who might be eligible for reperfusion therapy.Methods. The characteristics and outcomes of patients with a prehospital ECG were compared with those without a prehospital ECG in the National Registry of Myocardial Infarction 2 data base. Included in the analysis were those patients who presented to the hospital within 12 h of an acute myocardial infarction. Excluded were patients with an in-hospital infarction, transferred-in referrals and self-transported patients.Results. Prehospital ECGs were obtained in 3,768 (5%) of 66,995 National Registry of Myocardial Infarction 2 patients meeting study criteria. Median time from myocardial infarction symptom onset until hospital arrival was longer among those having a prehospital ECG (152 vs. 91 min, p < 0.001). However, once in the hospital, the prehospital ECG group experienced a shorter median time to the initiation of either thrombolysis (30 vs. 40 min, p < 0.001) or primary angioplasty (92 vs. 115 min, p < 0.001). The prehospital ECG group was more likely to receive thrombolytic therapy (43% vs. 37%, p < 0.001) and to undergo primary angioplasty (11% vs. 7%, p < 0.001). Also, the prehospital ECG group was more likely to undergo coronary arteriography (55% vs. 40%, p < 0.001), angioplasty (24% vs. 16%, p < 0.001) or bypass surgery (10% vs. 6%, p < 0.001). The in-hospital mortality rate was 8% in patients with a prehospital ECG and 12% in those without a prehospital ECG (p < 0.001). After adjusting for baseline covariates utilizing multiple logistic regression analysis, this mortality difference remained statistically significant (odds ratio 0.83, 95% confidence interval 0.71 to 0.96, p = 0.01).Conclusions. The prehospital ECG is infrequently utilized for diagnosing myocardial infarction, and among patients with a prehospital ECG, is associated with a longer time from symptom onset to hospital arrival. Despite these shortcomings, the prehospital ECG is a test that may potentially influence the management of patients with acute myocardial infarction through wider, faster in-hospital utilization of reperfusion strategies and greater usage of invasive procedures, factors that may possibly reduce short-term mortality. Efforts to implement the prehospital ECG more widely and more rapidly may be indicated.(J Am Coll Cardiol 1997;29:498–505)