INTRODUCTION The scales available to predict death and complications after acute coronary syndrome include angiographic studies and serum biomarkers that are not within reach of services with limited resources. Such services need specific and sensitive instruments to evaluate risk using accessible resources and information.
OBJECTIVE Develop a scale to estimate and stratify the risk of intrahospital death in patients with acute ST-segment elevation myocardial infarction.
METHODS An analytical observational study was conducted in a universe of 769 patients with acute ST-segment elevation myocardial infarction who were admitted consecutively to the Camilo Cienfuegos Provincial Hospital in Sancti Spíritus Province, Cuba, from January 2013 to March 2018. The fi nal study cohort included 667 patients, excluding 102 due to branch blocks, atrial fibrillation, drugs that prolong the QT interval, low life expectancy or history of myocardial infarction. The demographic variables of age, sex, skin color, classic cardiovascular risk factors, blood pressure, heart rate, blood glucose level, in addition to duration and dispersion of the QT interval with and without correction, left ventricular ejection fraction, and glomerular filtration rate were included in the analysis. Patients were categorized according to the Killip-Kimball Classification for degree of heart failure. A risk scale was constructed, the predictive ability of which was evaluated using the detectability index associated with an receiver-operator curve.
RESULTS Seventy-seven patients died (11.5%). Mean blood glucose levels were higher among the deceased, while their systolic and diastolic blood pressure, left ventricular ejection fraction, and glomerular filtration rate were lower than those participants discharged alive. Relevant variables included in the scale were systolic blood pressure, Killip-Kimball class, cardiorespiratory arrest, glomerular filtration rate, corrected QT interval dispersion rate, left ventricular ejection fraction, and blood glucose levels. The variable with the best predictive ability was cardiorespiratory arrest, followed by a blood glucose level higher than 11.1 mmol/L. The scale demonstrated a great predictive ability with a detectability index of 0.92.
CONCLUSIONS The numeric scale we designed estimates and stratifies risk of death during hospitalization for patients with ST-segment elevation myocardial infarction and has good metric properties for predictive ability and calibration.
KEYWORDS ST-segment elevation myocardial infarction, mortality, risk assessment, Cuba
INTRODUCTION Hypertension is one of the most studied risk factors for cardiovascular disease in adults; in children and adolescents, its global prevalence changes with age, from 1%–3% in children to 3.2% in adolescents. In adults, in addition to hypertension, several biochemical markers of cardiovascular risk have been identified. Confirming an association between these and hypertension in childhood and adolescence would allow for more timely diagnosis and monitoring of cardiovascular disease, since the presence of both the markers and hypertension would imply increased risk.
OBJECTIVE Confirm an association between biochemical risk markers of cardiovascular disease and hypertension in children aged 8 to 11 years.
METHODS A cross-sectional study of 373 children aged 8–11 years was conducted in 3 primary schools in the city of Santa Clara in central Cuba. The variables examined were age, sex, height, blood pressure, cholesterol, triglycerides, lipoproteins and apolipoproteins. The children were classified as normotensive, prehypertensive or hypertensive, based on blood pressure readings and percentiles for age, sex and height. Descriptive statistics were calculated for quantitative variables. A bivariate analysis, tests of independence for qualitative variables and a means comparison for quantitative variables (ANOVA and its nonparametric alternative, the Kruskal Wallis test) were performed. Fisher’s F-test and its associated probability value were employed.
RESULTS Some 32.2% of the children were prehypertensive and 5.1% hypertensive. Cholesterol and triglyceride values were significantly higher in hypertensive than in normotensive children (p = 0.028 and p = 0.047, respectively). HDL numbers were higher in normotensive children (p =0.001), and LDL numbers and the LDL/HDL ratio were higher in the hypertensive children, with differences between groups (p = 0.001 for both variables). There were differences between the three blood pressure categories for lipoprotein(a) and ApoA (p <0.001 and p = 0.001), for ApoB and for the ApoB/ApoA ratio (p <0.001 for both variables), with lower ApoA values and higher ApoB and ApoB/ApoA values in the hypertensive children.
CONCLUSIONS The biochemical risk markers most strongly associated with hypertension in children are ApoB values, LDL, lipoprotein(a), and LDL/HDL and ApoB/ApoA ratios.
KEYWORDS Adolescent, child, hypertension, apolipoproteins, cardiovascular diseases, risk factors, Cuba
INTRODUCTION Many clinical settings lack the necessary resources to complete angiographic studies, which are commonly used to predict complications and death following acute coronary syndrome. Corrected QT-interval dispersion can be useful for assessing risk of myocardial infarction recurrence.
OBJECTIVE Evaluate the relationship between corrected QT-interval dispersion and recurrence of myocardial infarction in patients with ST-segment elevation.
METHODS We conducted a prospective observational study of 522 patients with ST-segment elevation myocardial infarction admitted consecutively to the Camilo Cienfuegos General Provincial Hospital in Sancti Spiritus, Cuba, from January 2014 through June 2017. Of these, 476 were studied and 46 were excluded because they had other disorders. Demographic variables and classic cardiovascular risk factors were included. Blood pressure, heart rate, blood glucose, and corrected and uncorrected QT-interval duration and dispersion were measured. Patients were categorized according to the Killip-Kimball classification. Association between dispersion of the corrected QT-interval and recurrence of infarction was analyzed using a binary logistic regression model, a regression tree and receiver operator characteristic curves.
RESULTS Patients with recurrent infarction (56; 11.8%) had higher average initial blood glucose values than those who did not have recurrence; the opposite occurred for systolic and diastolic blood pressure and for left ventricular ejection fraction. Dispersion of the corrected QT-interval was a good predictor of infarction recurrence according to a multivariate analysis (OR = 3.09; 95% CI = 1.105–8.641; p = 0.032). Cardiac arrest is the variable that best predicts recurrence. No recurrence of infarction occurred in 97% of patients without cardiac arrest, left ventricular ejection fraction >45% and corrected QT-interval dispersion <80 ms.
CONCLUSIONS Risk of infarction recurrence is low in patients without cardiac arrest, with left ventricular ejection fraction >45% and with dispersion of corrected QT-interval <80 ms. Patients with corrected QT-interval dispersion ≥80 ms have greater risk of recurrence of infarction, which suggests that this variable could be used for stratification of risk following ST-segment elevation myocardial infarction.
KEYWORDS ST-elevation myocardial infarction, myocardial infarction, electrocardiography, chronic disease, risk assessment, Cuba
INTRODUCTION EKG remains a highly valuable tool for heart disease management. Corrected QT interval dispersion is a useful EKG parameter to assess prognosis in ischemic heart disease and specifically acute coronary syndrome. Understanding QT interval physiopathology helps assess importance of QT measurement in this context. Although increased QT dispersion is an ominous prognostic marker, its utility has not been evaluated for all types of acute coronary syndrome, even though in many circumstances it is the only tool available for diagnosing patients with equivocal EKG signs and/or atypical symptoms.
OBJECTIVE Describe corrected QT interval dispersion in acute coronary syndrome in three groups of patients—with ST elevation, without ST elevation, and without ST elevation with equivocal EKG signs—admitted to the intensive care unit of Celestino Hernández Robau University Hospital in Santa Clara, Cuba, from January 2010 through June 2011.
METHODS A descriptive retrospective study was conducted in 194 patients admitted with diagnosis of acute coronary syndrome. QT interval was measured and its dispersion calculated for the first EKG after symptom onset. Patterns were assessed for typical and atypical clinical presentations, and unequivocal and equivocal EKG signs.
RESULTS Nonclassifiable acute coronary syndrome was found in 6.7% of patients (13/194), the majority of whom had increased QT dispersion (76.9%, 10/13). There were significant differences in QT dispersion patterns between patients with typical and atypical presentations and between patients with equivocal and unequivocal EKG findings. In non-ST elevation acute coronary syndrome and nonclassifiable acute coronary syndrome with increased dispersion, atypical presentation was the most common (65.5%, 19/29; and 90%, 9/10, respectively).
CONCLUSION Corrected QT interval dispersion is a useful diagnostic tool for acute coronary syndrome, especially when patients present with atypical symptoms and equivocal EKG findings. Thus, it is a low-cost alternative in management of acute coronary syndrome in resource-poor settings.
KEYWORDS Risk factors, ischemic heart disease, acute coronary syndrome, myocardial ischemia, electrocardiography, QT interval dispersion, prognosis, Cuba
INTRODUCTION Hypertension and obesity in adults have been linked to increased EKG P-wave dispersion; the association has been shown in relation to hypertension, left ventricular hypertrophy and atrial enlargement. Though studies in children have linked P-wave dispersion to left ventricular hypertrophy, scant pediatric literature relates P-wave dispersion to hypertension and obesity.
OBJECTIVE Assess the association of P-wave dispersion with blood pressure and nutritional status in a pediatric population.
METHODS This cross-sectional study is part of the PROCDEC II project for pediatric hypertension diagnosis and control in Santa Clara, Cuba. Twelve-lead EKG and four blood pressure readings were conducted on a sample of 656 children aged 8–11 years. Blood pressure <90th percentile for age, sex and height was considered normal; 90th–95th percentile, prehypertension; and >95th percentile, hypertension. The main study variables were P-wave dispersion and systolic, diastolic and mean arterial pressure (MAP). Secondary variables were sex, height, weight, and body mass index. Comparisons of means, analysis of variance and linear correlations were done.
RESULTS Mean P-wave dispersion differed significantly (p ≤0.05) among normotensive (30.10 ms), prehypertensive (32.99 ms) and hypertensive children (39.14 ms), as did mean MAP (p <0.05). P-wave dispersion and MAP were significantly correlated in prehypertensive and hypertensive children. Most overweight and obese children with high P-wave dispersion were prehypertensive or hypertensive.
CONCLUSIONS Associations observed between P-wave dispersion and MAP in normotensive, prehypertensive and hypertensive children suggest potential for early detection of EKG patterns showing vulnerability. Given the relationship between increased P-wave dispersion and hypertension already described in adults, use of P-wave dispersion could be a simple, economical and noninvasive method of predicting risk of hypertensive cardiomyopathy in prehypertensive and hypertensive children; this in turn could guide timely, effective treatment and secondary prevention. Similar studies on a larger sample are needed to corroborate these results.
KEYWORDS Arterial hypertension, pediatrics, prevention, electrocardiogram, ECG, EKG, mean arterial pressure, P-wave dispersion, Cuba
