The distinction between coronary and myocardial reperfusion after thrombolytic therapy by clinical markers of reperfusion

Objectives. We sought to examine the hypothesis that rapid resolution of ST-segment elevation in acute myocardial infarction (AMI) patients with early peak creatine kinase (CK) after thrombolytic therapy differentiates among patients with early recanalization between those with and those without adequate tissue (myocardial) reperfusion.Background. Early recanalization of the epicardial infarct-related artery (IRA) during AMI does not ensure adequate reperfusion on the myocardial level. While early peak CK after thrombolysis results from early and abrupt restoration of the coronary flow to the infarcted area, rapid ST-segment resolution, which is another clinical marker of successful reperfusion, reflects changes of the myocardial tissue itself.Methods. We compared the clinical and the angiographic results of 162 AMI patients with early peak CK (≤12 h) after thrombolytic therapy with (group A) and without (group B) concomitant rapid resolution of ST-segment elevation.Results. Patients in groups A and B had similar patency rates of the IRA on angiography (anterior infarction: 93% vs. 93%; inferior infarction: 89% vs. 77%). Nevertheless, group A versus B patients had lower peak CK (anterior infarction: 1,083 ± 585 IU/ml vs. 1,950 ± 1,216, p < 0.01; and inferior infarction: 940 ± 750 IU/ml vs. 1,350 ± 820, p = 0.18) and better left ventricular ejection fraction (anterior infarction: 49 ± 8, vs. 44 ± 8, p < 0.01; inferior infarction: 56 ± 12 vs. 51 ± 10, p = 0.1). In a 2-year follow-up, group A as compared with group B patients had a lower rate of congestive heart failure (1% vs. 13%, p < 0.01) and mortality (2% vs. 13%, p < 0.01).Conclusions. Among patients in whom reperfusion appears to have taken place using an early peak CK as a marker, the coexistence of rapid resolution of ST-segment elevation further differentiates among patients with an opened culprit artery between the ones with and without adequate myocardial reperfusion.     

急性心肌梗死患者溶栓后血浆中脑钠素浓度变化的研究

目的研究血中脑钠素(BNP)水平与急性心肌梗死溶栓后左心室射血分数(LVEF)和心肌缺血程度的关系。方法将198例顺序入选的急性心肌梗死行链激酶静脉溶栓治疗的患者分为溶栓成功组(105例)和溶栓未成功组(93例),检测所有患者的血BNP水平及测定LVEF,比较溶栓成功组与溶栓未成功组LVEF>40%和LVEF≤40%的BNP水平。结果溶栓成功组BNP水平明显低于溶栓未成功组的BNP水平(725.4±169.8)ng/L(P<0.05),溶栓成功组和未成功组中LVEF>40%患者的BNP水平[(107.7±46.5)ng/L,(488.5±88.9)ng/L]明显低于LVEF≤40%患者的BNP水平[(515.5±121.2)ng/L,(856.7±129.5)ng/L,P<0.01]。结论急性心肌梗死患者血中BNP水平与LVEF和心肌缺血程度有关。     

Reperfusion arrhythmias: are they only a marker of epicardial reperfusion or continuing myocardial ischemia after acute myocardial infarction?

Reperfusion arrhythmias are associated with epicardial reperfusion but may also be a sign of vascular reperfusion injury which can be seen as no-reflow phenomenon on coronary angiography and predicts in-hospital complications and recovery of left ventricular (LV) function. No-reflow phenomenon (thrombolysis in myocardial infarction [TIMI] 相似文献   

Changes in Autonomic Tone Following Thrombolytic Therapy for Acute Myocardial Infarction:

Heart Rate Variability in Acute MI. Introduction: Little data are available on changes in autonomic tone during the first 24 hours of acute infarction in patients undergoing thromholytic therapy. Particularly, the association of changes in autonomic tone to reperfusion of the infarctrelated artery has not been evaluated in man. Heart rate variability (HRV) is a noninvasive tool to assess cardiac autonomic tone, which carries prognostic information in postinfarction patients. Methods and Results: To assess changes in autonomic tone with ungiographically assessed success of thrombolysis in patients with acute infarction, the proportion of adjacent RR intervals different by greater than 50 msec (pNN50) was analyzed from 24-hour Holler monitoring initiated before the start of thrombolytic therapy in 103 consecutive patients. Mean heart rate (HR) and pNN50 were available in 95 of 103 patients and were separately analyzed for the first hour after initiation of thrombolysis (reperfusion phase) and the first 24 hours. As assessed by coronary angiography 90 minutes after start of thrombolysis, 74 patients (78%) had successful coronary artery reperfusion. HR averaged 72 ± 13/min for the first hour in all 95 patients and 74 ± 13/min for the first 24 hours. The respective values for pNN50 were 11±2%± 11±7% for the first hour and 9±7%± 9±2% for the first 24 hours. Patients with inferior myocardial infarction (MI) had a lower mean HR of 72 ± 12/min versus 76 ± 13/min (P = 0±11) and a higher pNN50 (11±2%± 9±8% versus 7±6%± 8±3%, P = 0±01) compared to patients with anterior MI. The mean HR correlated weakly with pNN50 (r = -0±33, P < 0±01). For patients with coronary artery patency after 90 minutes, mean HR was 70 ± 12/min for the first hour compared to 80 ± 13/min for patients without (P = 0±003). For the first 24 hours, these values were 72 ± 12/min compared to 80 ± 14/min (P = 0±02). For the first hour, pNN50 averaged 12±6%± 12±4% for patients with successful reperfusion compared to 6±6%± 7±3% for patients without (P = 0±024). For the first 24 hours, these values were 9±2%± 8±5% compared to 11±5%± 11±3% (P = NS). Patients with inhospital ventricular fibrillation (n = 8) had a higher mean HR throughout the first 24 hours (88 ±16/min vs 73 ± 12/min, P = 0±008) compared to patients with an uneventful course. Additionally, there was a trend toward a lower HRV in patients with ventricular fibrillation. Conclusion: Thrombolysis-induced reperfusion of the infarct-related artery results in a higher vagal tone during the early hours of MI as compared to failed reperfusion. This finding is independent from intfarct location and associated with a trend toward a lower incidence of ventricular fibrillation during the acute phase of infarction.     

Comparison of late results of percutaneous coronary intervention among stable patients ≤65 versus >65 years of age with an occluded infarct related artery (from the Occluded Artery Trial)

Although opening an occluded infarct-related artery >24 hours after myocardial infarction in stable patients in the Occluded Artery Trial (OAT) did not reduce events over 7 years, there was a suggestion that the effect of treatment might differ by patient age. Baseline characteristics and outcomes by treatment with percutaneous coronary intervention (PCI) versus optimal medical therapy alone were compared by prespecified stratification at age 65 years. A p value <0.01 was prespecified as significant for OAT secondary analyses. The primary outcome was death, myocardial infarction, or New York Heart Association class IV heart failure. Patients aged >65 years (n = 641) were more likely to be female, to be nonsmokers, and to have hypertension, lower estimated glomerular filtration rates, and multivessel disease compared to younger patients (aged ≤65 years, n = 1,560) (p <0.001). There was no significant observed interaction between treatment assignment and age for the primary outcome after adjustment (p = 0.10), and there was no difference between PCI and optimal medical therapy observed in either age group. At 7-year follow-up, younger patients tended to have angina more often compared to the older group (hazard ratio 1.21, 99% confidence interval 1.00 to 1.46, p = 0.01). The 7-year composite primary outcome was more common in older patients (p <0.001), and age remained significant after covariate adjustment (hazard ratio 1.42, 99% confidence interval 1.09 to 1.84). The rate of early PCI complications was low in the 2 age groups. The trend toward a differential effect of PCI in the young versus the old for the primary outcome was likely driven by measured and unmeasured confounders and by chance. PCI reduces angina to a similar degree in the young and old. In conclusion, there is no indication for routine PCI to open a persistently occluded infarct-related artery in stable patients after myocardial infarction, regardless of age.     

Rapid myoglobin analysis to assess coronary artery reperfusion after acute myocardial infarction

Background: Coronary artery reperfusion significantly improves outcome in patients with acute myocardial infarction. A noninvasive method for assessing reperfusion in the early stage of infarction should be helpful in patient management. Hypothesis:We sought to assess whether release pattern of myoglobin is helpful in identifying patients with and without reperfusion following thrombolytic therapy for myocardial infarction. Methods: Myoglobin was measured before thrombolysis, half hourly for 4 h, then every 2 h for 10 h. Myoglobin was analyzed using a ward-based “rapid” and automated analyzer that yielded quantitative results within 10 min of blood collection. Results: In the 15 patients with coronary reperfusion, the time from thrombolysis to peak myoglobin levels (mean ± SD, 2.4 ± 1.5 h) was significantly lower than in nonreperfused patients (5.1 ± 2.9, p < 0.01). As an indicator for reperfusion, a doubling of myoglobin 1 h after streptokinase achieved a sensitivity of 80%, a specificity of 80%, and a predictive accuracy of 80%. Conclusions: The difference in myoglobin release kinetics is useful in identifying patients without coronary reperfusion and should aid in their management.     

Abnormal Q waves on the admission electrocardiogram of patients with first acute myocardial infarction: Prognostic implications

Background: Q waves developed in the subacute and persisting into the chronic phase of myocardial infarction (MI) usually signify myocardial necrosis. However, the mechanism and significance of Q waves that appear very early in the course of acute MI (<6 h from onset of symptoms), especially if accompanied by ST elevation, are probably different. Hypothesis: This study assesses the prognostic implications of abnormal Q waves on admission in 2,370 patients with first acute MI treated with thrombolytic therapy <6 h of onset of symptoms. Results: Patients with abnormal Q waves in ≥2 leads with ST-segment elevation (n = 923) were older than patients without early Q waves (n = 1,447) (60.6 ±11.9 vs. 58.8 ±11.9 years, respectively; p = 0.0003), and had a greater incidence of hypertension (34.3 vs. 30.5% p = 0.05) and anterior MI (60.6 vs. 41.1 % p<0.0001). Time from onset of symptoms to therapy was longer in patients with Q waves upon admission (208 ± 196 vs. 183 ± 230 min; p = 0.01). Peak serum creatine kinase (2235 ± 1544 vs. 1622 ± 1536 IU; p<0.0001), prevalence of heart failure during hospitalization (13.8 vs. 7.0%, p<0.0002), hospital mortality (8.0 vs. 4.6% p = 0.02), and cardiac mortality (6.6 vs. 4.5%, p = 0.11) were higher in patients with anterior MI and with abnormal Q waves than in those without abnormal Q waves upon admission. There was no difference in peak creatine kinase, prevalence of heart failure, in-hospital mortality, and cardiac mortality between patients with and without abnormal Q waves in inferior MI. Multivariate regression analysis confirmed that mortality is independently associated with presence of Q waves on admission (odds ratio 1.61; 95% CI 1.04–2.49; p = 0.04 for all patients; odds ratio 1.65; 95% CI 0.97–2.83; p=0.09 for anterior wall MI. Conclusion: Abnormal Q waves on the admission electrocardiogram (ECG) are associated with higher peak creatine kinase, higher prevalence of heart failure, and increased mortality in patients with anterior MI. Abnormal Q waves on the admission ECG of patients with inferior MI are not associated with adverse prognosis.     

Coronary and left ventricular angiographic anatomy and prognosis of survivors of first acute myocardial infarction

To relate coronary anatomy and left ventricular function to prognosis, 197 of 269 consecutive survivors of a first myocardial infarction (MI) ≤ 60 years old underwent prospective cardiac catheterization a median of 2 weeks after admission and were followed up for a median of 24 months (range 12 to 61). Seventy-two patients were excluded from angiography because of early death (9), severe noncoronary disease (44), MI complications (6), or patient refusal (13). The prevalence of multivessel disease was low (30%) and unrelated to the site of MI or presence of Q waves but was increased in patients with previous angina pectoris (p = 0.05) or those in Killip class II or III (p = 0.02). There were only 8 deaths from heart disease. The survival rate at 12 months was 97 ± 1% and at 24 and 36 months, 95 ± 2%. Nineteen patients underwent coronary revascularization surgery. As the number of deaths was small, the differences in survival between patients with single or multivessel disease and normal or depressed ejection fractions failed to reach significance. Survivors of a first MI ≤ 60 years old have a low prevalence of multivessel disease and a good prognosis.     

Long-term prognosis of late spontaneous reperfusion after failed thrombolysis for acute myocardial infarction

BACKGROUND: Early reperfusion improves left ventricular (LV) function and survival after acute myocardial infarction (MI). Thrombolytic therapy achieves early patency of the infarct artery in about two-thirds of patients. In nearly half of the remaining patients, in whom early reperfusion was not achieved with thrombolytic therapy, the infarct artery might reopen by the time of predischarge angiography. However, the impact of such late spontaneous reperfusion after failed thrombolytic therapy on LV function and long-term survival remained unclear. HYPOTHESIS: This study was undertaken to assess implication of late spontaneous reperfusion after failed thrombolytic therapy on LV function and long-term survival after acute MI. METHODS: The study consisted of 198 patients with anterior acute MI who underwent thrombolytic therapy and predischarge angiography: 160 patients with infarct artery patent early and late after therapy (persistent patency), 17 patients with infarct artery occluded early after therapy but patent at predischarge angiography (late spontaneous reperfusion), and 21 patients with infarct artery occluded early and late after therapy (persistent occlusion). RESULTS: Persistent patency was associated with enhanced improvement in LV ejection fraction (7.7 +/- 11.8%) compared with late spontaneous reperfusion (0.0 +/- 9.6%, p = 0.03) and persistent occlusion (-1.4 +/- 9.7%, p = 0.003). Persistent patency was associated with better long-term survival than with late spontaneous reperfusion (p < 0.001) and persistent occlusion (p < 0.001). Multivariate analysis comparing persistent patency and late spontaneous reperfusion showed that early reperfusion was an independent predictor of long-term survival. CONCLUSION: Late spontaneous reperfusion after failed thrombolytic therapy was associated with poor LV function and long-term survival, emphasizing the importance of early reperfusion.     

Eligibility for and benefit of thrombolytic therapy in inferior myocardial infarction: Focus on the prognostic importance of right ventricular infarction

Objectives. This study was undertaken to determine eligibility for and benefit of thrombolytic therapy in patients with acute inferior myocardial infarction with or without right ventricular involvement.Background. Right ventricular involvement commonly complicates acute inferior myocardlal infarction and is considered to have prognostic relevance. We hypothesized that the presence of right ventricular infarction, diagnosed early by ST segment elevation in the right precordial lead (V₄R), may be of clinical importance in identifying patients who will benefit most from thrombolytic therapy.Methods. We studied 200 consecutive patients with acute inferior myocardial infarction to assess the prognostic impact of right ventricular infarction in those considered eligible or ineligible for reperfusion therapy. Prognostic analyses were based on the in-hospital period and a 1- to 6-year follow-up (mean [±SD] 37 ± 12 months).Results. ST segment elevation in lead V₄R was a reliable marker of right ventricular infarction (sensitivity 88%, specificity 78%, diagnostic efficiency 83%) in 107 patients (54%) with inferior myocardial infarction. Seventy-one eligible patients (36%) received thrombolytic therapy and had a lower mortality (8% [6 of 71]) and complication (31% [22 of 71]) rate than ineligible patients (mortality rate 25% [32 of 129], p < 0.001; complication rate 56% [72 of 129], p < 0.01). However, the overall benifit of thrombolysis was restricted to patients with right ventricular infarction complicating acute inferior myocardial infarction (with vs. without thrombolysis, respectively: mortality rate 10% vs. 42%, p < 0.005; complication rate 34% vs. 54%, p < 0.05). In the absence of right ventricular infarction, no difference was observed in the mortality (7% vs. 6%, p = NS) and major in-hospital complication (27% vs. 29%, p = NS) rates, whether or not the patient underwent thrombolytic therapy. Posthospital course over 37 ± 12 months was not different in patients with and without right ventricular infarction but was best in all patients considered for reperfusion therapy.Conclusions. During acute inferior myocardial infarction, the right precordial electrocardiogram is a simple but promising variable to identify a subgroup of patients with an unfavorable course who will benefit most from thrombolytic therapy.     

Myocardial infarction in young adults: Risk factors and natural history

The risk factors and clinical course of 165 patients under 40 years of age (mean age 35) having an initial myocardial infarction (MI) (Group I) were compared to 100 patients over 40 (mean age 50) (Group II). Six risk factors were analyzed: smoking 20 pack-years, hyperlipidemia, hypertension, family history of ischemic disease, diabetes mellitus, and obesity. Only two patients in Group I and six patients in Group II had no risk factors, but the mean number of risk factors in Group I (3) differed from Group II (2) (p< 0.05). Group I had only 18% of patients without either obesity, hyperlipidemia, hypertension, or diabetes mellitus as risk factors while Group II had 41 patients with similar findings (p< 0.001). Group I had hyperlipidemia, obesity, and family history more commonly than did Group II while hypertension was more frequent in the older patients. A prior history of angina was present in nearly half of Group I and II but physical exertion just prior to MI was more common in Group I (32%) than in Group II (20%) (p < 0.05). Death at the time of MI was more frequent in Group II (p < 0.001) but congestive failure occurred in 17% of both groups. On follow-up, 45% of both groups had no complications, and the rates of subsequent MI and angina pectoris were similar in both groups. However, late death was less frequent in Group I than in Group II. Patients under 40 with myocardial infarction have more risk factors than those over 40 which may play some role in pathophysiology of young myocardial infarction. Physical exertion at the time of myocardial infarction is more common in younger patients. The complication rate is similar in both young and older myocardial infarction patients but the mortality rate, both early and late, is lower in young myocardial infarction patients.     

Time as an adjunctive agent to thrombolytic therapy

Thrombolytic therapy has dramatically reduced mortality following acute myocardial infarction (MI) with the major effect coming fromearly achievement of infarct-related artery patency. A major factor in achieving rapid reperfusion is early treatment with thrombolytic therapy. Recent trials have shown that mortality can be reduced if time to treatment is shortened: In the Thrombolysis in Myocardial Infarction (TIMI) 2 trial, for each hour earlier that thrombolytic therapy was started, approximately 10 lives were saved per 1000 patients treated. Thus, one must considertime as an adjunctive agent to thrombolytic therapy. There are four components of the time delay between the onset of MI and achievement of reperfusion: (1) patient delays in seeking medical attention; (2) transport delays; (3) the so-called door to needle time, the interval between the patient's arrival at the medical facility and the initiation of thrombolytic therapy; and (4) thrombolytic reperfusion time, the time between the administration of thrombolytic therapy and the achievement of reperfusion. Efforts to reduce each of these components will lead to additive benefits in improving time to reperfusion and survival of patients with acute MI.     

Medical and surgical management of early Q wave myocardial infarction. I. Effects of surgical reperfusion on survival, recurrent myocardial infarction, sudden death and functional class at 10 or more years of follow-up

To define the outcome of patients given medical or surgical therapy for Q wave myocardial infarction, 387 patients were followed up for 10 to 13 years (mean 11.4). On study entry the groups had similar distributions for variables such as mean age, gender, previous myocardial infarction, abnormal creatine kinase activity, area of infarction, number of vessels diseased and clinical classification. The hospital mortality rate of the medical versus surgical group was 11.5% (23 of 200) versus 5.8% (11 of 187) (p = 0.07). Early reperfusion (that is, less than or equal to 6 h) resulted in a lower mortality rate than did medical therapy--2% (2 of 100) versus 11.5% (23 of 200) (p less than 0.05)--whereas the hospital mortality rate with late reperfusion was 10.3% (9 of 87). The long-term mortality rate of the medical and surgical groups was 41% (82 of 200) versus 27% (51 of 187) (p = 0.0007) with use of an adjusted Cox proportional hazards model. In the survivors, the differences between medical and surgical groups in recurrent myocardial infarction, mortality associated with reinfarction and sudden death were prospectively followed and evaluated by the life table method. Recurrent myocardial infarction was not prevented by surgical reperfusion or medical therapy (23% in both groups), however, the mortality rate in patients with recurrent infarction was higher in the medical therapy group--36.6% (15 of 41) versus 17.5% (7 of 40) (p = 0.04). The mortality difference did not depend on early or late surgical reperfusion. In the in-hospital survivors, the incidence of sudden death was 17.5% in the medical (31 of 177) versus 7.4% (13 of 176) in the surgical group (p = 0.01). This difference was much more pronounced in the early reperfusion group. Functional class was significantly lower than that for medical therapy in the early reperfusion but not the late reperfusion group. Thus, in comparable groups given medical and surgical therapy for acute myocardial infarction and followed up for greater than or equal to 10 years, surgical reperfusion appears to offer improved longevity in selected cases (when implemented early) but does not prevent recurrent myocardial infarction. The associated mortality with recurrent myocardial infarction is less as is the incidence of sudden death. Finally, lower functional class occurs most often in patients given early reperfusion.     

Does angina the week before protect against first myocardial infarction in elderly patients?

Mortality rates for coronary artery disease are greater in elderly patients. Although prodromal angina occurring shortly before an acute myocardial infarction (MI) has protective effects against ischemia, this effect has not been well documented in older patients. This study investigated whether angina 1 week before a first MI provides protection in this group of patients. A total of 290 consecutive elderly (>64 years old, n = 143) and adult patients (<65 years old, n = 147) with a first MI were examined to assess the effect of preceding angina on the short- and long-term prognosis. Elderly patients with a history of prodromal angina were less likely than those without angina to experience in-hospital death, heart failure, or the combined end point of in-hospital death and heart failure (6% vs 20.4%, p = 0.02; 10% vs 23.7%, p = 0.07; 14% vs 32.3%, p = 0.01, respectively). Left ventricular function was more frequently depressed (ejection fraction <40%) in elderly patients without (44.8%) than with (26%, p = 0.04) preinfarction angina, and the incidence of arrhythmias (complete heart block and ventricular fibrillation) was greater in the former group (16.1% vs 4%, p = 0.03). Multivariate analysis confirmed that the presence of preinfarction angina was an independent predictor of in-hospital death and heart failure in older patients (odds ratio 0.28, p = 0.009). The occurrence of angina 1 week before a first MI may confer protection against in-hospital adverse outcomes, and may preserve left ventricular function in older patients.     

Age-Specific Differences in the Use of Thrombolytic Therapy and Hospital Outcomes in Patients with Acute Myocardial Infarction: A Community-Wide Perspective

Background: Relatively limited information is available about recent, and trends over time, use of thrombolytic therapy in patients of different ages hospitalized with acute myocardial infarction and the association between use of thrombolytic therapy and hospital outcomes. Methods: We conducted an observational study of 5601 residents of the Worcester, Massachusetts, metropolitan area (1990 census = 437,000) with confirmed acute myocardial infarction in all local hospitals during 6 one-year periods between 1990 and 1999. Results: Despite relatively stable use of thrombolytic therapy between 1990 and 1995, decreases in the use of thrombolytic therapy in all patients with acute myocardial infarction were observed in 1997 and 1999. There was a 1.6 fold decrease in the use of thrombolytic therapy between 1990 and 1999 in patients <65 years. Patients 65–74 years (33.7% 1990; 11.7% 1999) and those 75 years and older (10.8% 1990; 6.7% 1999) experienced marked decreases in the receipt of thrombolytic therapy over time. Use of thrombolytic therapy was associated with reduced hospital mortality in each of the four age-specific groups under study (<55, 55–64, 65–74, 75) through the degree of benefit on hospital death rates associated with the use of thrombolytic therapy was attenuated after adjustment for additional confounders. Conclusions: Our findings indicate recent declines in the use of thrombolytic therapy in middle-aged and elderly patients with acute myocardial infarction. The impact of thrombolytic therapy on hospital outcomes was observed in each of our age strata under study though the magnitude of absolute and relative benefit varied according to age. Miniabstract. Declines in the use of thrombolytic therapy were observed between 1900 and 1999 in a population-based sample of patients with acute myocardial infarction. Use of thrombolytic therapy was associated with improved hospital survival to varying degrees in each of the age groups under study.     

Additional ST segment elevation during the first hour of thrombolytic therapy: an electrocardiographic sign predicting a favorable clinical outcome.

OBJECTIVES. The aim of this study was to investigate the significance of further ST elevation that occurs during the 1st h of thrombolytic therapy before the expected resolution. BACKGROUND. Early resolution of ST segment elevation is commonly accepted as a marker of clinical reperfusion during thrombolytic therapy for acute myocardial infarction. Using frequent electrocardiographic recordings, we observed in some patients further ST elevation that occurred during hour 1 of thrombolysis before the expected resolution. METHODS. To investigate the significance of this pattern, we classified 177 consecutive patients with a first acute myocardial infarction into two groups: Group A, 98 patients with ST elevation > or = 1 mm above the initial ST elevation during the 1st h of thrombolytic therapy, and Group B, 79 patients without this finding. RESULTS. Although the presence or absence of additional ST elevation was not associated with a clinical or prognostic difference in patients with a first inferior or posterior acute myocardial infarction, its presence indicated a more favorable clinical outcome and prognosis in patients with anterior infarction. Among the patients with anterior infarction the 65 patients in Group A had a higher ejection fraction (44 +/- 9% vs. 35 +/- 11%, p < 0.01), less heart failure (15% vs. 35%, p = 0.02) and a lower in-hospital mortality rate (0% vs. 8%, p = 0.04) than did the 37 patients from Group B. CONCLUSIONS. Additional ST elevation early during thrombolytic therapy in patients with anterior infarction suggests a favorable clinical outcome and thus may be indicative of successful reperfusion.     

Prognostic value of predischarge radionuclide ventriculography at rest and exercise after acute myocardial infarction treated with thrombolytic therapy or primary coronary angioplasty

Background: Previous studies have demonstrated the prognostic value of radionuclide ventriculography at rest and exercise in patients post myocardial infarction (MI). The number of studies in patients treated with modern reperfusion techniques, including thrombolysis or primary angioplasty, however, is limited. Hypothesis: The aim of this study was to evaluate the prognostic significance of predischarge radionuclide ventriculography at rest and exercise in patients with acute MI treated with thrombolysis or primary angioplasty. Methods: A total of 272 consecutive patients with acute MI who were randomized to thrombolysis or primary coronary angioplasty underwent predischarge resting and exercise radionuclide ventriculography. Left ventricular ejection fraction at rest, decrease in ejection fraction during exercise >5 units below the resting value, angina pectoris, ST-segment depression, and exercise test ineligibility were related to subsequent cardiac events (cardiac death, nonfatal reinfarction) during follow-up. Results: During a mean follow-up of 30 ± 10 months, cardiac death occurred in 11 (4%) patients and nonfatal reinfarction in 14 (5%) patients. Resting left ventricular ejection fraction was the major risk factor for cardiac death. In patients with an ejection fraction <40%, cardiac death occurred in 16% compared with 2% in those with an ejection fraction ≥ 40% (p = 0.0004). In addition, cardiac death tended to be higher in patients ineligible than in those eligible for exercise testing (11 vs. 3%, p = 0.08). None of the other exercise variables (decrease in ejection fraction during exercise >5 units below the resting value, angina pectoris or ST-segment depression) were predictive for cardiac death. When all exercise test variables in each patient were combined and expressed as a risk score, a low risk (n = 185) and a higher risk (n = 87) group of patients could be identified, with cardiac death occurring in 1 and 10%, respectively. As the predictive accuracy of a negative test was high, radionuclide ventriculography was of particular value in identifying patients at low risk for cardiac death. Radionuclide ventriculography was not able to predict recurrent nonfatal MI. Conclusion: In patients with MI treated with thrombolysis or primary angioplasty, radionuclide ventriculography may be helpful in identifying patients at low risk for subsequent cardiac death. In this respect, left ventricular ejection fraction at rest was the major determinant. Variables reflecting residual myocardial ischemia were of limited prognostic value. Identification of a large number of patients at low risk allows selective use of medical resources during follow-up in this subgroup and has significant implications for the cost effectiveness of reperfusion therapies.     

Comparison of gender-specific mortality in patients < 70 years versus ≥ 70 years old with acute myocardial infarction

The aim of the present study was to investigate the gender-specific mortality after acute myocardial infarction in those aged < 70 years versus ≥ 70 years. The present study consisted of 2,677 consecutive patients with acute myocardial infarction who had undergone coronary angiography within 24 hours after the onset of symptoms. The patients were divided into 2 groups: 1,810 patients < 70 years old and 867 patients ≥ 70 years old. Women were older and had a greater incidence of hypertension and diabetes mellitus and a lower incidence of current smoking and previous myocardial infarction in both groups. The in-hospital mortality rate was significantly greater in women ≥ 70 years old age than in men ≥ 70 years old (16.2% vs 9.3%, respectively; p = 0.003) but was comparable between women and men in patients < 70 years old (5.7% vs 4.9%, respectively; p = 0.59). On multivariate analysis, the association between female gender and in-hospital mortality in patients ≥ 70 years old remained significant (odds ratio 1.78, 95% confidential interval 1.05 to 3.00), but the gender difference was not observed in patients < 70 years old (odds ratio 1.09, 95% confidence interval 0.53 to 2.24). In conclusion, female gender was associated with in-hospital mortality after acute myocardial infarction in patients ≥ 70 years old but not in patients < 70 years old.     

Immediate coronary angioplasty versus intravenous streptokinase in acute myocardial infarction: Left ventricular ejection fraction,hospital mortality and reinfarction

Objectives. The purpose of the present study was to compare intravenous Streptokinase therapy with immediate coronary angioplasty without antecedent thrombolytic therapy with regard to left ventricular function and hospital mortality and reinfarction.Background. Despite the widespread use of intravenous thrombolytic therapy and immediate percutaneous transluminal coronary angioplasty, these two strategies to treat patients with an acute myocardial infarction have only recently been compared in randomized trials. Coronary angioplasty has been shown to result In a higher patency rate of the Infant-related coronary artery, with a less severe residual stenotic lesion, compared with streptokinase therapy, but whether this more favorable coronary anatomy results in clinical benefit remair to be established.Methods. We studied 301 patients with acute myocardial infarction randomly assigned to undergo immediate coronary angioplasty without antecedent thrombolytic therapy or to receive intravenous streptokinase therapy. Before discharge left ventricular ejection fraction was measured by radionuclide scanning.Results. The in-hospital mortality rate in the streptokinase group was 7% (11 of 149 patients) compared with 2% (3 of 152 patients) in the angioplasty group (p = 0.024). In the streptokinase group recurrent myocardial infarction occurred in 15 patients (10%) versus in 2 (1%) in the angioplasty group (p < 0.001). Either death or nonfatal reinfarction occurred in 23 patients (15%) in the streptokinase group and in 5 patients (3%) in the angioplasty group (p = 0.001). Left ventricular ejection fraction was 44 ± 11% (mean ± SD) in the streptokinase group versus 50 ± 11% in the angioplasty group (p < 0.001).Conclusions. These findings indicate that immediate coronary angioplasty without antecedent thrombolytic therapy results in better left ventricular function and lower risk of death and recurrent myocardial infarction than treatment with intravenous streptokinase.     

Predictive Value of Late Potentials after Myocardial Infarction in the Thrombolytic Era

Background: The value of the signal-averaged electrocardiogram (ECG) for prediction of arrhythmic events (AE) after myocardial infarction (MI) has been well established. The current incidence of AE in the first year after Ml is remarkably lower than that reported in the 1980s. In this study, we compared the prevalence and the predictive value of late potentials (LP) in patients with Ml treated with either conventional or reperfusion therapy. Methods: A total of 433 patients (age 62 ± 10 years, 350 men) recovering from acute Ml were prospectively analyzed. Two hundred seven patients had conventional therapy (group A), and 226 had reperfusion therapy (group B) within 12 hours of the onset of symptoms: 145 of group B patients received thrombolytic agents, whereas 81 underwent direct or rescue angioplasty. Standard signal-averaged variables were recorded (filter range 40–250 Hz) 10 ± 6 days (range 5–30 days) after Ml. LP were defined as being present if 2 of the following were met: fQRS <114 ms, RMS40 20 μV, LAS40 <38 ms (criterion 1), and if QRS 120 ms (criterion 2). Results: LP were found in 33% versus 21%, P = 0.004 (criterion 1) and in 13% versus 8%, P = 0.057 (criterion 2) of group A and group B patients, respectively. During a mean follow-up of 24 ± 19 months (range 5 days to 48 months), there were 22 AE (5%). The AE rate for patients with conventional therapy was significantly higher in those with LP than in those without LP: 12% versus 4%; P = 0.03 (criterion 1) and 30% versus 3%; P = 0.00003 (criterion 2). The AE rate for patients with reperfusion therapy was similar in patients with and without LP: 9% versus 3%, P = 0.09 (criterion 1) and 12% versus 3%, P = 0.14 (criterion 2). Multivariate analysis indicated that the presence of LP based on criterion 2 was the strongest independent predictor of AE in patients with Ml treated with conventional therapy. Conclusion: In this study, reperfusion therapy influenced the prevalence of LP. The predictive value of LP for serious AE in the postinfarction period was remarkably affected by thrombolysis and/or interventional catheter therapy.