Variables electrocardiográficas asociadas a la aparición de eventos cardiovasculares adversos en el infarto agudo de miocardio sin elevación del segmento ST / Electrocardiographic variables associated to the occurrence of adverse cardiovascular events in non-ST elevation acute myocardial infarction

Introducción: La frecuencia de infarto agudo de miocardio sin elevación del segmento ST se está incrementando y, con ella, los resultados adversos en pacientes con enfermedad coronaria isquémica aguda. Objetivo: Identificar las variables electrocardiográficas asociadas a la aparición de eventos cardiovasculares adversos en el infarto agudo de miocardio sin elevación del segmento ST. Método: Se realizó un estudio transversal, de tipo correlacional, con 68 pacientes con infarto agudo de miocardio sin elevación del segmento ST atendidos en el Hospital Arnaldo Milián Castro, en la provincia de Villa Clara. Se estudiaron los hallazgos electrocardiográficos y eventos cardiacos adversos durante el ingreso. Se hicieron análisis bivariados para establecer la relación de ambas variables, utilizando el estadígrafo chi cuadrado y el riesgo relativo. Resultados: Los hallazgos electrocardiográficos más frecuentes fueron la inversión de la onda T (#8805; 2mm), depresión del segmento ST y el QT corregido largo mediante la fórmula de Bazzet. El 26,5 por ciento presentaron eventos cardiovasculares adversos. La depresión del segmento ST, el QT largo corregido y la elevación del segmento ST en aVR se asociaron significativamente con eventos adversos intrahospitalarios (p lt; 0,05). Conclusiones: La asociación de la depresión del segmento ST, la elevación del segmento ST en aVR y el QT largo corregido con la ocurrencia de eventos cardiovasculares adversos intrahospitalarios, sugiere que estos hallazgos se pueden tener en cuenta como posibles indicadores de evolución desfavorable en pacientes con infarto agudo de miocardio sin elevación del segmento ST(AU)

Introduction: The frequency of non-ST elevation acute myocardial infarction is on the increase, and so is the number of adverse results in patients with acute ischemic coronary disease. Objective: Identify the electrocardiographic variables associated to the occurrence of adverse cardiovascular events in non-ST elevation acute myocardial infarction. Method: A cross-sectional correlational study was conducted of 68 patients with non-ST elevation acute myocardial infarction cared for at Arnaldo Milián Castro Hospital in the province of Villa Clara. Attention was paid to electrocardiographic findings and adverse cardiac events occurring during the hospital stay. Bivariate analyses were performed to establish the relationship between the two variables, using the chi square statigram and relative risk estimation. Results: The most common electrocardiographic findings were T-wave inversion (#8805; 2 mm), ST depression and long corrected QT by Bazzet's formula. Of the total study subjects 26.5 percent had adverse cardiovascular events. ST depression, long corrected QT and ST elevation in aVR were significantly associated to in-hospital adverse events (p < 0.05). Conclusions: Association of ST depression, ST elevation in aVR and long corrected QT with the occurrence of adverse in-hospital cardiovascular events suggests that these findings may be taken into account as possible indicators of an unfavorable evolution in patients with non-ST elevation acute myocardial infarction(AU)

Caracterización clínica y angiográfica según sexo de pacientes con síndrome coronario agudo sin supradesnivel del segmento ST / Clinical and angiographic characterization according to sex of patients with acute coronary syndrome without ST segment elevation

Ischemic Heart Disease is the leading cause of death and of potential years of life lost in Chile. The most frequent acute presentation of this group of pathologies is the Acute Coronary Syndrome (ACS) without ST segment elevation. According to the literature, there is a proportion of patients with non-ST elevated ACS in which coronary angiography reveals a mild coronary lesion or even shows no detectable lesion at all. This scenario is more common in women than in men. Compared with men, women with non-ST elevated ACS are older than men and more frequently have hypertension. Furthermore, women are less likely to have previous cardiac diseases, and are less common to present serum troponin rise at admission. In Chile, there are no previous studies about the differences between sexes in this disease. The objective of this study is to determine if there are major differences between sexes in aspects like clinical and angiographic findings in patients with non-ST elevated ACS. The study used a database of 1900 consecutive patients who were submitted for coronary angiography and had been previously diagnosticated with non-ST elevated ACS, between the years 2001-2017. Clinical assessment, laboratory and angiographic results were collected and analyzed to establish major differences considering p<0,05. 69% of patients were men. When comparing, the proportion of smokers was greater in men, who also more frequently had progressive worsening of angina or treatment-resistant chest pain as clinical presentations. Furthermore, previous coronary bypass surgery, previous percutaneous coronary intervention and previous myocardial infarction were more common in men. As to women, they were older and more frequently had hypertension and/or hypothyroidism. Unstable angina as a clinical presentation was more usual than in men and electrocardiographic findings as a negative T-wave in the anterior wall, evolutive segment changes and left branch bundle block were also more common. In addition, serum troponin rise was more frequent than in men. There was no difference in risk stratification with TIMI score. When comparing angiographic findings, women had more frequently mild lesions or no lesions at all (44% in women versus 27% in men). In conclusion, clinical aspects are different in between sexes as to presence of comorbidities, cardiovascular risk factors and previous cardiovascular disease. Clinical presentation is also different, as to symptoms and as to electrocardiographic findings and laboratory exams. At last, and as evidence suggests, there is a greater proportion of women with mild coronary lesions or without lesions than in men when comparing angiographic findings. (AU)