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Introduction and Objectives: In patients with acute myocardial infarction, a number of variables in the initial ECG are useful prognostic indicators. The presence of ST-segment elevation, however, usually indicates the need for reperfusion therapy. The aims of this study were to investigate sex differences in the ECGs of patients with ST-elevation myocardial infarction (STEMI) and to look for a possible association between sex and marked ST-segment elevation., Methods: A prospective observational longitudinal study of consecutive patients (n=1422) who were admitted early for a first STEMI to one of two coronary units was carried out. Initial ECG parameters were analyzed for sex differences. Multivariate analysis was performed to identify variables associated with marked ST-segment elevation (i.e., total ST-segment elevation >11 mm, according to the upper tertile of the frequency distribution)., Results: In women (n=336), Q-wave myocardial infarction was observed more often in the initial ECG (19% versus 15.6%; P< .03), the total ST-segment elevation was lower (10+/-6.6 mm versus 11.1+/-7.9 mm; P< .004), and marked ST-segment elevation was less common (26.4% versus 35.5%; P< .005). There was an independent inverse association between female sex and marked ST-segment elevation (odds ratio=0.70; 95% confidence interval, 0.52-0.96; P< .02)., Conclusions: In patients with STEMI, female sex was associated with a lower total ST-segment elevation and there was an independent inverse association with marked ST-segment elevation.

Objective: Indication of temporary pacemakers in patients during acute myocardial infarction was widely studied in the pre-thrombolytic era without having determined whether the generalization of fibrinolysis might have changed the overall incidence and significance of temporary pacemakers. Our aim was to determine the incidence and the prognostic significance of insertion of temporary pacemakers in patients with acute myocardial infarction., Patients and Methods: In a study involving 1,239 patients consecutively admitted to hospital with acute myocardial infarction we studied clinical characteristics and prognosis depending on temporary pacemaker insertion or not. We performed an univariate analysis on in-hospital mortality and those selected variables were introduced in to a logistic regression analysis., Results: A temporary pacemaker was indicated in 55 patients (4.4%), prophylactically in 22% and therapeutically in 78%. Temporary pacemakers were inserted in 55% of the patients with advanced AV block and in the 10% of the patients with bundle-branch block. Pacemaker insertion was associated with higher number of affected leads in the ECG, and higher CK peak, regardless of the association with thrombolysis. The following complications were more often observed in patients with temporary pacemakers: atrial fibrillation, heart failure, right bundle-branch block, advanced atrioventricular block and in-hospital mortality (45.4 vs 10.2%; p < 0.001). Need for a temporary pacemaker was less frequent in patients treated with thrombolytics compared with those not treated (3.0 vs 6.1%; p < 0.02). Pacemaker insertion had an independent value for predicting in-hospital mortality (OR = 5.51; 95% CI, 2.71-11.19)., Conclusion: The insertion of a temporary pacemaker in acute myocardial infarction is less frequent nowadays than on the pre-thrombolytic era. Pacemaker insertion is associated with higher indices of infarct extension and in-hospital mortality, having independent prognostic value on the in-hospital mortality.

Objectives: The study of incidence and prognostic significance of supraventricular tachyarrhythmias in patients with acute myocardial infarction., Patients and Methods: Prospective study on 1,239 patients consecutively admitted because of a diagnosis of acute myocardial infarction. Clinical characteristics, indexes of myocardial infarction and complications were analysed., Results: Supraventricular tachyarrhythmias were observed in 116 (9.3%) cases: atrial fibrillation in 96 (7.7%); atrial tachycardia in 15 (1.2%); and atrial flutter in the remaining five cases (0.4%). Patients with supraventricular tachyarrhythmias were older, and presented higher heart rate, lower blood pressure, a higher number of affected leads in ECG, and higher Killip class. A higher creatine kinase peak and a lower left ventricular ejection fraction were associated with the presence of supraventricular tachyarrhythmias. Predictors of supraventricular tachyarrhythmias were: age, systolic blood pressure, number of affected leads in ECG, and congestive heart failure at admission. The following complications were found more frequently in patients with supraventricular tachyarrhythmias: bundle-branch block, complete A-V block, ventricular tachycardia, ventricular fibrillation; heart failure; stroke; and mortality, in-hospital 18.1% vs 11.1% (p < 0.05) and one-year, 38.7% vs 18.4% (p < 0.001). The logistic regression model showed that supraventricular tachyarrhythmias had no independent prognostic value on mortality., Conclusions: The appearance of supraventricular tachyarrhythmias during the acute phase of myocardial infarction is a relatively frequent finding, often associated with older age and larger infarctions. Supraventricular tachyarrhythmias are accompanied by higher short and long-term mortalities, although there is no independent prognostic significance.

To assess the current incidence and meaning of left bundle-branch block associated with acute myocardial infarction we studied 1,239 patients consecutively admitted in three hospitals. Left bundle branch block was present in 42 cases (3.3%). Compared to the patients without left bundle-branch block, those with left bundle-branch block were older (70 +/- 8.8 versus 63.9 +/- 11.4 years; p < 0.001), and had a more prevalent history of diabetes, angina, myocardial infarction and heart failure. Left bundle-branch block was associated more frequently with female gender and poor left ventricular ejection fraction. Patients with left bundle branch block were admitted with a longer interval from the onset of the symptoms (7.8 +/- 6.3 versus 5.4 +/- 6.7 hours; p < 0.01) and received in a lesser rate thrombolytics agents (21% versus 56%; p < 0.001), than those without left bundle-branch block. Complications significatively associated with left bundle-branch block were: complete AV block; heart failure and one-year mortality (40.4% versus 19.5%, p < 0.01). Female gender, age and heart failure were independent predictors of mortality whereas left bundle-branch block was not. In conclusion, current incidence of left bundle-branch block in acute myocardial infarction is lower than that referred in the pre-thrombolytic era. Left bundle-branch block is accompanied by a low rate of thrombolysis, whereas a higher mortality rate of these patients seems to depend on their clinical characteristics.

Introduction and Objectives: Complete atrioventricular block (CAVB) during inferior acute myocardial infarction (AMI), characterizes a high-risk subgroup of patients. This study was designed to determine the incidence and meaning of CAVB associated with inferior AMI and their peculiarities in relation to thrombolytic therapy., Methods: Prospective and multicenter, involving 605 patients consecutively admitted with inferior AMI. We studied clinical characteristics and complications occurring during hospitalization and one-year follow-up were monitored., Results: CAVB was found in 57 (9.4%) patients and was more frequently associated with: right ventricular involvement (35% vs 10%; p < 0.001), higher indexes of infaret size: ST elevated ECG leads (4.67 +/- 1.67 vs 4.1 +/- 1.4; p < 0.01) and peak of creatinkinase (2,219 +/- 1,543 vs 1,589 +/- 1,203; p < 0.01). Patients with CAVB had a higher incidence of cardiogenic shock (14% vs 5%; p < 0.05) and in-hospital mortality (21% vs 8.7%). CAVB had an independent value for predicting in-hospital mortality (odds ratio 2.7, 95% confidence interval, 1.3-5.5). CAVB appeared more frequently in the first hour of evolution (91% vs 41%; p < 0.01); its duration was shorter than 6 hours in a higher ratio (80% vs 5%; p < 0.01), and in- hospital mortality was lower (8.5 vs 40.9%; p < 0.05), in patients receiving thrombolytic treatment compared with patients without this treatment., Conclusions: CAVB is a relatively frequent complication of inferior AMI and is often associated with larger infarcts, high incidence of complications and mortality. Earlier appearance, shorter duration and fewer in-hospital mortalities seem to characterize those CAVBs occurring in patients treated with thrombolytics.

Introduction: Intracranial hemorrhage in acute myocardial infarction, under thrombolytic therapeutic, ranges from 0.3 to 3% in different trials. We carried out a study to stabilised the incidence of this complication in ours patients, as well as to analyze its characteristics and asses the presence the predictive factors., Methods: We retrospectively reviewed 997 consecutive patients with acute myocardial infarction treated with thrombolytic agents. We used two different protocols in two consecutive periods of time. Protocols differ in the age of the patients, the thrombolytic agent and its interval of applications. We analyze the intracranial hemorrhage incidence rate in each period, as well as its relations with the age of the patients, the sex and the thrombolytic agent used. We also analyze the possible predictive risk factors: cerebral-vascular disease, hypertension, diabetes, etc., Results: The overall rate of intracranial hemorrhage was 1.6%, higher in the patients of the second period (0.9% vs 1.9%, p = NS). The age over 70 years don't show a significant increase of this incidence (1.7% vs 1.5%). The APSAC group have shown a greater rate of hemorrhage (4%) than streptokinase (0.8%) and rTPA (1.2%). Cerebral-vascular disease and hypertension background were the two factors more frequently related to hemorrhage. The mortality rate was 68.7%., Conclusion: The intracranial hemorrhage is a severe complication of thrombolytic therapy with a relative low incidence, but in our experience, higher than described in multicenter studies. There are several factors related that we would to take into account when is applied this therapy.

The new protocols of actuation in acute myocardial infarction thrombolysis have increased the number of patients treated, and have changed their characteristics. To assess the influence that this event has had in the complications incidence and mortality rate, we revise 704 infarcts treated with thrombolytic in a coronary unit, during 8 years. We separate two groups: 1) Patients treated since november 1983 to december 1988 following the established protocol at the beginning of this therapeutic (n = 328). 2) Patients treated since this date to july 1991, with a new protocol that include older than 70 years patients, moore than 6 hours of therapeutics delay and use of another thrombolytics, moreover streptokinase (n = 376). These changes have increased the number of thrombolysis in the second group (24.6 vs 49.1%; p < 0.001). Nevertheless being a higher group of risk we have found neither a significant mortality increase (6.40 vs 7.71%; p = NS), nor complications related to the thrombolysis: The incidence of major hemorrhages were 2.13 vs 1.06% (p = NS), cerebral hemorrhages 0.91 vs 1.6% (p = NS), hypotension related to the thrombolytics 15.55 vs 5.85% (p < 0.001). Neither has had significant difference in the incidence of reinfarcts (6.42 vs 5%; p = NS). In conclusion, the great number of thrombolysis realized nowadays, due to the actuation protocols changes, have increased significantly, neither the complications related with this therapeutic, nor the mortality rate, nor the reinfarcts number.

We assessed the incidence of clinical heart failure in patients with acute myocardial infarction admitted to a coronary care unit and treated with intravenous streptokinase. We compared 2 groups of patients: 1) treated group: patients with acute myocardial infarction admitted to the unit in the last 3 years and treated with intravenous streptokinase, following a protocol established previously. 2) CONTROL GROUP: patients with the same characteristics and selection criteria as for the treated group, admitted to the unit during the previous 2 years and conventionally treated, without thrombolytic therapy. We assessed, in both groups, the incidence of heart failure at the time of admission, at discharge and the total incidence in the unit, following the Killip and Kimball criteria. The total incidence of heart failure was higher in the control group than in the treated group (43.8 vs 19.1%, p less than 0.001). This difference was even greater when the comparison was made with the reperfused patients (43.8% vs 18%, p less than 0.001). Heart failure incidence at the time the patients were discharged from de unit was also higher in the control group (21.2% vs 4.3%, p less than 0.001). When we considered severe heart failure (III-IV Killip Group) we also observed a significant difference between both groups. In conclusion, the incidence and the severity of clinical heart failure were lower in patients treated with streptokinase than in those treated conventionally.