Is female sex an independent predictor of in-hospital mortality in acute myocardial infarction?

OBJECTIVE: To assess whether female sex is a factor independently related to in-hospital mortality in acute myocardial infarction. METHODS: Of 600 consecutive patients (435 males and 165 females) with acute myocardial infarction, we studied 13 demographic and clinical variables obtained at the time of hospital admission through uni- and multivariate analysis, and analyzed their relation to in-hospital death. RESULTS: Females were older (p<0.001) and had a higher incidence of hypertension (p<0.001). Males were more frequently smokers (p<0.001). The remaining risk factors had a similar incidence among both sexes. All variables underwent uni- and multivariate analysis. Through univariate analysis, the following variables were found to be associated with in-hospital death: female sex (p<0.001), age >70 years (p<0.001), the presence of previous coronary artery disease (p=0.0004), previous myocardial infarction (p<0.001), infarction in the anterior wall (p=0.007), presence of left ventricular dysfunction (p<0.001), and the absence of thrombolytic therapy (p=0.04). Through the multivariate analysis of logistic regression, the following variables were associated with in-hospital mortality: female sex (p=0.001), age (p=0.008), the presence of previous myocardial infarction (p=0.02), and left ventricular dysfunction (p<0.001). CONCLUSION: After adjusting for all risk variables, female sex proved to be a variable independently related to in-hospital mortality in acute myocardial infarction.

[Chest pain units: state of the art of the management of patients with chest pain in the emergency department]. / Unidades de dolor torácico: estado actual del manejo de pacientes con dolor torácico en los servicios de urgencias.

Chest pain is one of the most common reasons for patients coming to emergency departments. Most of these individuals end up being hospitalized due to uncertainty of the cause of their complaint. This aggressive and defensive attitude is taken by emergency physicians because some 10 to 30% of these patients actually have acute coronary syndrome. As the admission electrocardiogram and serum CK-MB level have a sensitivity of about 50% for the diagnosis of acute myocardial infarction, serial evaluation is mandatory for non-low risk patients. Inspite of this knowledge, an average of 2-3% of patients with acute myocardial infarction are erroneously released from emergency departments, what is responsible for expensive malpractice suits in the United States. Chest Pain Units were introduced in emergency practice two decades ago to improve medical care quality, reduce inappropriate hospital discharges, reduce unnecessary hospital admissions and reduce medical costs, thus making patient's assessment cost-effective. This is achieved mostly with the use of systematic diagnostic protocols by qualified and trained personnel in the emergency department setting and not in the coronary care unit.

Chest pain in the emergency room. Importance of a systematic approach.

OBJECTIVE: To evaluate the efficiency of a systematic diagnostic approach in patients with chest pain in the emergency room in relation to the diagnosis of acute coronary syndrome (ACS) and the rate of hospitalization in high-cost units. METHODS: One thousand and three consecutive patients with chest pain were screened according to a preestablished process of diagnostic investigation based on the pre-test probability of ACS determinate by chest pain type and ECG changes. RESULTS: Of the 1003 patients, 224 were immediately discharged home because of no suspicion of ACS (route 5) and 119 were immediately transferred to the coronary care united because of ST elevation or left bundle-branch block (LBBB) (route 1) (74% of these had a final diagnosis of acute myocardial infarction [AMI]). Of the 660 patients that remained in the emergency room under observation, 77 (12%) had AMI without ST segment elevation and 202 (31%) had unstable angina (UA). In route 2 (high probability of ACS) 17% of patients had AMI and 43% had UA, whereas in route 3 (low probability) 2% had AMI and 7% had UA. The admission ECG has been confirmed as a poor sensitivity test for the diagnosis of AMI (49%), with a positive predictive value considered only satisfactory (79%). CONCLUSION: A systematic diagnostic strategy, as used in this study, is essential in managing patients with chest pain in the emergency room in order to obtain high diagnostic accuracy, lower cost, and optimization of the use of coronary care unit beds.

Efficacy of a diagnostic strategy for patients with chest pain and no ST-segment elevation in the emergency room.

PURPOSE: To evaluate the efficacy of a systematic model of care for patients with chest pain and no ST segment elevation in the emergency room. METHODS: From 1003 patients submitted to an algorithm diagnostic investigation by probability of acute ischemic syndrome. We analyzed 600 ones with no elevation of ST segment, then enrolled to diagnostic routes of median (route 2) and low probability (route 3) to ischemic syndrome. RESULTS: In route 2 we found 17% acute myocardial infarction and 43% unstable angina, whereas in route 3 the rates were 2% and 7%, respectively. Patients with normal/non-specific ECG had 6% probability of AMI whereas in those with negative first CKMB it was 7%; the association of the 2 data only reduced it to 4%. In patients in route 2 the diagnosis of AMI could only be ruled out with serial CKMB measurement up to 9 hours, while in route 3 it could be done in up to 3 hours. Thus, sensitivity and negative predictive value of admission CKMB for AMI were 52% and 93%, respectively. About one-half of patients with unstable angina did not disclose objective ischemic changes on admission. CONCLUSION: The use of a systematic model of care in patients with chest pain offers the opportunity of hindering inappropriate release of patients with ACI and reduces unnecessary admissions. However some patients even with normal ECG should not be released based on a negative first CKMB. Serial measurement of CKMB up to 9 hours is necessary in patients with medium probability of AMI.

Chest pain in the emergency room. Importance of a systematic approach

OBJECTIVE: To evaluate the efficiency of a systematic diagnostic approach in patients with chest pain in the emergency room in relation to the diagnosis of acute coronary syndrome (ACS) and the rate of hospitalization in high-cost units. METHODS: One thousand and three consecutive patients with chest pain were screened according to a pre-established process of diagnostic investigation based on the pre-test probability of ACS determinate by chest pain type and ECG changes. RESULTS: Of the 1003 patients, 224 were immediately discharged home because of no suspicion of ACS (route 5) and 119 were immediately transferred to the coronary care united because of ST elevation or left bundle-branch block (LBBB) (route 1) (74% of these had a final diagnosis of acute myocardial infarction [AMI]). Of the 660 patients that remained in the emergency room under observation, 77 (12%) had AMI without ST segment elevation and 202 (31%) had unstable angina (UA). In route 2 (high probability of ACS) 17% of patients had AMI and 43% had UA, whereas in route 3 (low probability) 2% had AMI and 7% had UA. The admission ECG has been confirmed as a poor sensitivity test for the diagnosis of AMI (49%), with a positive predictive value considered only satisfactory (79%). CONCLUSION: A systematic diagnostic strategy, as used in this study, is essential in managing patients with chest pain in the emergency room in order to obtain high diagnostic accuracy, lower cost, and optimization of the use of coronary care unit beds.

Chest pain in the emergency room. Importance of a systematic approach.

OBJECTIVE: To evaluate the efficiency of a systematic diagnostic approach in patients with chest pain in the emergency room in relation to the diagnosis of acute coronary syndrome (ACS) and the rate of hospitalization in high-cost units. METHODS: One thousand and three consecutive patients with chest pain were screened according to a pre-established process of diagnostic investigation based on the pre-test probability of ACS determinate by chest pain type and ECG changes. RESULTS: Of the 1003 patients, 224 were immediately discharged home because of no suspicion of ACS (route 5) and 119 were immediately transferred to the coronary care united because of ST elevation or left bundle-branch block (LBBB) (route 1) (74% of these had a final diagnosis of acute myocardial infarction [AMI]). Of the 660 patients that remained in the emergency room under observation, 77 (12%) had AMI without ST segment elevation and 202 (31%) had unstable angina (UA). In route 2 (high probability of ACS) 17% of patients had AMI and 43% had UA, whereas in route 3 (low probability) 2% had AMI and 7 % had UA. The admission ECG has been confirmed as a poor sensitivity test for the diagnosis of AMI ( 49%), with a positive predictive value considered only satisfactory (79%). CONCLUSION: A systematic diagnostic strategy, as used in this study, is essential in managing patients with chest pain in the emergency room in order to obtain high diagnostic accuracy, lower cost, and optimization of the use of coronary care unit beds.

[Hospital mortality in acute myocardial infarction: is it possible to predict using admission data?]. / Mortalidade hospitalar no infarto agudo do miocárdio: E possível prever utilizando dados de admissão?

PURPOSE: To identify clinical variables on admission that are related to hospital mortality in acute myocardial infarction (AMI) and to generate a mathematic model to predict accurately this mortality. METHODS: Prospective study with 347 consecutive patients with AMI in which clinical variables related to mortality were identified by univariate and multivariate analysis. The mathematic model generated by multivariate logistic regression analysis was applied in each patient to determine his/her probability (P) of hospital death. Model's accuracy was validated by reliability and discrimination tests. RESULTS: Admission variables directly and independently related to hospital mortality: female gender, age, absence of history of hypertension, history of previous infarction, non-inferior AMI and Killip class. These six variables, when present cumulatively, showed increasing mortality rates. Mean P value for non-survivors was significantly greater than for survivors (43.2 +/- 31.4% vs 9.1 +/- 12.5%, p < 0.00001). Reliability of the model to predict death, assessed by stratifying patients in three risk groups (low, medium and high) or continuously (by linear regression analysis) showed excellent predictive performance. Discrimination between survivors and non-survivors, assessed by C-index (concordance probability), disclosed 85% rate of success. CONCLUSION: Risk variables can be used in a mathematic model that is capable of predicting accurately in-hospital mortality of each patient with AMI. Mortality prediction can allow physicians to be more efficient in assessing risk-benefit ratios in these patients when faced with therapeutic decisions.

[Early and delayed cardiac mortality after acute myocardial infarction in the pre-thrombolytic era. Prognosis value of an ergometric test and coronary arteriography]. / Mortalidade cardíaca precoce e tardia pós-infarto agudo do miocárdio na era pré-trombólise. Valor prognóstico do teste ergométrico e da coronariografia.

PURPOSE: To determine the relationship among clinical data, attenuated treadmill stress test (ST), cinecoronaryarteriography (CINE), ejection fraction (EF) with early-late mortality in patients after acute myocardial infarction (AMI). METHODS: Prospective study in 96 consecutive patients aged < 70 with AMI that were submitted to ST and CINE. Assessment of cardiac mortality was made 1-3 years post-AMI (period I) and at the end of follow-up (7-10 years-period II). RESULTS: First year and 10th year mortalities were 8% and 36%, respectively. Positive predictive value for cardiac death in period I was 10% for ST, 7% for multivessel coronary artery disease (MVCAD) and 9% for left ventricular ejection fraction (LVEF) < 30, while in period II they were 45%, 42% and 50%, respectively. Actuarial survival analysis (Kaplan-Meyer) disclosed mortality rates of 53% and 20% (p = 0.06) on period II for positive and negative ST, respectively, 45% and 22% (p < 0.03) for MVCAD and single-vessel disease, respectively, and 73% and 35% (p < 0.001) for those with and without left main coronary artery obstruction, respectively. In the multivariate regression analysis (Cox's model), only MVCAD (p < 0.002), LVEF < 30 (p < 0.003), positive ST (p < 0.007) and post-AMI angina (p < 0.01) were independently related to late mortality. CONCLUSION: Both attenuated ST and CINE are poor predictors of post-AMI early and late mortalities. However, multivariate regression analysis disclosed positive ST, MVCAD and LVEF < 30 as independent variables related to late mortality. This data indicate that myocardial ischemia, number of obstructed coronary arteries and poor left ventricular systolic function are the true determinants of post-infarction cardiac mortality.

[Are the spontaneous coronary recanalization and the coronary collateral circulation really important in the left ventricular preservation in acute myocardial infarct?]. / A recanalização coronária espontânea e a circulação colateral coronária são realmente importantes na preservação ventricular esquerda no infarto agudo do miocárdio?

PURPOSE: To determine if maintenance of residual blood flow to culprit coronary artery in acute myocardial infarction is important in preserving left ventricular systolic function. METHODS: Prospective study of 63 consecutive survivors of acute myocardial infarction in the prethrombolytic era that were submitted to cinecoronary angiography and 30 degrees RAO left ventriculography on the 4th week. Culprit coronary artery patency and collateral circulation were correlated with global and segmental left ventricular contractility. RESULTS: Spontaneous coronary recanalization correlated significantly with better left ventricular systolic function only in patients with anterior wall myocardial infarction. This relationship was stronger with segmental than with global contractility. Besides, it was seen that absence of recanalization of pre-septal left anterior descending coronary artery occlusion resulted in significantly worse global and segmental left ventricular systolic function than post-septal occlusion, resulting in left ventricular aneurysm in all patients (2/3 of recanalized patients versus 1/3 of post-septal occlusions). Collateral circulation to culprit coronary artery correlated significantly with better global and segmental left ventricular contractility only in patients with inferior wall myocardial infarction. CONCLUSION: In acute anterior wall myocardial infarction spontaneous coronary artery recanalization is associated with better global and segmental left ventricular systolic function, specially if the occlusion is of pre-septal localization, while collateral circulation is not related to better contractility. In acute inferior wall myocardial infarction one sees the reverse.

[Arrhythmogenic right ventricular dysplasia]. / Displasia ventricular direita arritmogênica.

PURPOSE: To evaluate the clinical findings and complementary investigation to support the diagnosis of arrhythmogenic right ventricular dysplasia. METHODS: Six males with a mean age of 40 years old with episodes of sustained ventricular tachycardia with left bundle branch block pattern. All patients were submitted to a clinical investigation, EKG X rays and echocardiograms. In five patients an electrophysiologic study was performed. All patients were treated with anti-arrhythmic drugs. RESULTS: Palpitation was the most common complaint. T-wave inversion in leads V1-V3 was present in 4 patients. An epsilon wave was noted in 2 patients. The chest X ray was abnormal in only 1 patient. All patients had an abnormal echocardiogram, with consisted in the dilatation of the outflow tract of the RV and hypocontractility. In 2 patients aneurysm of the basal RV free wall below tricuspid valve were detected. Ventricular post-excitation waves were present in 4 patients. After a mean follow-up of 37 months, 5 patients were asymptomatic with anti-arrhythmic drugs and one in therapeutic adjustment. CONCLUSION: In patients with ventricular tachycardia with left bundle branch block pattern, the diagnosis of arrhythmogenic right ventricular dysplasia was substantiated by echocardiographic data and electrocardiographic findings such a T-wave inversion during sinus rhythm and ventricular post-excitation waves. The results obtained with anti-arrhythmic drugs in our study group, suggest that drug therapy should be the first and best approach to treat patients with this type of pathology.

[Torsades de Pointes: analysis of 105 episodes]. / Torsades de Pointes: análise de 105 episódios.

PURPOSE: To analyze episodes of Torsades de Pointes (TP), in search of its electrocardiographic characteristics. PATIENTS AND METHODS: We analyzed 105 episodes of TP, in 4 patients using quinidine and diuretics, recorded by 24-hour Holter monitoring. The following parameters were studied; ventricular repolarization out of TP, rhythm disturbances before TP; EKG characteristics of the onset, the bouts and the end of the TP. RESULTS: Ventricular repolarization, out of the TP, was abnormal, with the presence of U-waves at the end of the T-waves, resulting in prolongation of the QT (QU) interval. The U-wave voltage was noted to be cycle-length dependent. Ventricular bigeminy preceded TP in 100 episodes (95%) and the mean interval between both parameters was 18 +/- 16 min. The onset of the TP episodes showed the "short/long/short cycle rule", hereby called "pre-pause cycle", "preparing cycle" and "trigger cycle" respectively. The rotatory QRS-T morphology around the baseline, was seen in 75% of episodes, at the beginning or throughout the bout. Monomorphic ventricular tachycardia pattern was seen in the other 25% of episodes. Termination of bouts was sudden in all cases, and persistent ventricular bigeminy led to another bout in 90 episodes (85%). CONCLUSION: In TP patients, there is enlargement of QT intervals mostly due to U-waves appearance. The U-waves seen in these cases, probably have an important role in the genesis of TP and are probably related to ventricular after-potentials (triggered activity). Ventricular bigeminy is a premonitory sign of TP in patients using class 1A antiarrhythmic drugs. Persistent ventricular bigeminy post-TP episodes is a strong indicator of another bout of TP. The onset of TP is more important than its morphology for the correct diagnosis of this arrhythmia.

[Is coronary cineangiography more accurate than early bicycle ergometry test in the identification of high-risk acute myocardial infarction survivors?]. / E a cinecoronariografia mais acurada que o teste ergométrico precoce na identificação de sobreviventes de infarto agudo do miocárdio de alto risco?

PURPOSE: To determine if attenuated early treadmill stress testing is more or less accurate than cinecoronary arteriography in the identification of high-risk acute myocardial infarction (AMI) survivors. PATIENTS AND METHODS: In a prospective study 96 non-selected and consecutive AMI survivors underwent cinecoronary arteriography in the 4th week of hospitalization and were followed up for a period of 3 to 39 (21.7 +/- 11.0) months. One-half of the patients were randomly submitted to an attenuated heart rate-limited treadmill stress testing in the 3rd week. Seven patients were lost in the follow-up. Of the remaining 89 patients 5 died of cardiac causes. Cardiac events (death, reinfarction, angina and heart failure) occurred in 26 patients. Multivessel coronary artery disease was found in 67 patients (75%) and mean left ventricular ejection fraction was 49.1 +/- 15.6%. Positive treadmill stress testing for myocardial ischemia occurred in 20 of 43 patients (46%). RESULTS: All patients who died of cardiac causes or who had a cardiac event had multivessel coronary artery disease, the mean left ventricular ejection fraction was 38.6 +/- 16.6% and 45.2 +/- 16.4%, respectively, and two-thirds of patients had positive stress testing. For cardiac death, multivessel coronary artery disease had better sensitivity than positive stress testing and left ventricular ejection fraction less than 0.3 (100% vs 67% vs 20%, respectively) while ejection fraction had better specificity than stress testing and multivessel coronary artery disease (87% vs 55% vs 21%, respectively). Stress testing had a better positive predictive value than multivessel coronary artery disease and ejection fraction (53% vs 38% vs 36%, respectively while multivessel coronary artery disease had better negative predictive value than stress testing and ejection fraction (100% vs 77% vs and 70%, respectively). The association of data obtained from cinecoronarography study between themselves and with positive treadmill stress testing did not significantly improve the sensitivities, specificities and predictive values in relation to the results obtained by isolated data. CONCLUSION: In survivors of acute myocardial infarction cinecoronary arteriography is not more accurate than, treadmill stress testing and both have limited value in the identification of patients who are candidates for cardiac death or events in the first few years after AMI. A negative stress testing and coronary arteriography (one-vessel disease) is more informative than a positive one.