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Biomedical subjects

C A Polanczyk

Publications and source records attributed to C A Polanczyk.

31 records · Page 2Linked to original sources
PubMed1998

Effect of partial arrhythmia suppression with amiodarone on heart rate variability of patients with congestive heart failure.

BACKGROUND: Some antiarrythmic agents that may increase mortality rates have been shown to reduce heart rate variability in patients with heart failure. Amiodarone is a potent antiarrhythmic agent that may reduce mortality rates in heart failure, but little is known about its effects on heart rate variability. METHODS AND RESULTS: The purpose of this study was to evaluate the effect of partial arrhythmia suppression by amiodarone on indexes of heart rate variability in patients with heart failure. Ten clinically stable patients in New York Heart Association class II-III received amiodarone during a 4-week period (600 mg every day for 14 days and 300 mg every day for 16 days), and 24-hour Holter recordings were performed before and after treatment. Heart rate variability indexes were calculated by a semiautomatic method that applies a 20% filter to the temporal series, excluding ectopy and compensatory pauses. After amiodarone administration, there was a significant reduction in pNN50 from 8% +/- 7% to 3% +/- 2% (p < 0.05) and there was a trend toward reduction in rMSSD (p = 0.06). Other time domain indexes did not change significantly. Spectral analysis demonstrated a significant reduction of low-frequency components (421 +/- 122 to 151 +/- 25 msec2; p < 0.05) and total power (1503 +/- 314 to 609 +/- 144 msec2, p < 0.05). Multivariate analysis showed that the observed reduction in pNN50 was strongly associated with the number and the reduction of ventricular premature contractions before and after amiodarone administration (r2 = 0.94; p < 0.01). CONCLUSIONS: These findings indicate that despite the use of software corrections for arrhythmia, short-term time domain indexes of heart rate variability may be affected by partial suppression of ectopy.

Amiodarone↗
PubMed1998

Effect of diabetes mellitus on the presentation and triage of patients with acute chest pain without known coronary artery disease.

PURPOSE: Patients with diabetes and acute chest pain may be admitted to hospitals more frequently than patients without diabetes because physicians suspect atypical presentations for ischemic heart disease. This study aimed to determine whether the presentation of acute myocardial infarction and risk for major cardiac complications differs among patients without known coronary artery disease who do or do not have diabetes. PATIENTS AND METHODS: Data from an emergency department of an urban teaching hospital on the medical histories, physical examinations, and electrocardiograms of 2,694 subjects with acute chest pain and without known coronary artery disease were prospectively recorded. RESULTS: Diabetes was present in 301 (11%) patients. Compared with patients without diabetes, patients with diabetes were more likely to be < or = 60 years old (51% versus 20%) and to have a history of hypertension (70% versus 35%) or high blood cholesterol (35% versus 19%). A discharge diagnosis of acute myocardial infarction was made in 25 diabetic (8%) and in 148 nondiabetic (6%; P = 0.16) patients. A major cardiac complication occurred in two patients with diabetes (0.7%) and in 20 patients without diabetes (0.8%; P = 1.0). Patients with and without diabetes who had atypical chest pain complaints had similar rates of myocardial infarction (3% and 4%, respectively; P = 0.6). Patients with diabetes were more likely to be hospitalized (67% versus 47%; P = 0.001) both before and after adjusting for clinical and electrocardiographic data. CONCLUSIONS: For patients with acute chest pain without a prior history of coronary artery disease, diabetes was not associated with a higher rate of acute myocardial infarction or complications. However, diabetes was associated with a higher rate of hospitalization in this population, suggesting that physicians have a lower threshold for admission to the hospital of patients with diabetes.

Acute Disease↗
PubMed1998

Cardiac troponin I as a predictor of major cardiac events in emergency department patients with acute chest pain.

OBJECTIVES: We sought to evaluate the diagnostic and prognostic value of cardiac troponin I (cTnI) in emergency department (ED) patients with chest pain. BACKGROUND: Although cTnI has been shown to correlate with an increased risk for complications in patients with unstable angina, the prognostic significance of this assay in the heterogeneous population of patients who present to the ED with chest pain is unclear. METHODS: cTnI and creatine kinase-MB fraction (CK-MB) mass concentration were collected serially during the first 48 h from onset of symptoms in 1,047 patients > or =30 years old admitted for acute chest pain. Sensitivity, specificity and receiver operating characteristic curves were calculated for cTnI and CK-MB collected in the first 24 h. RESULTS: The sensitivity, specificity and positive predictive value of cTnI for major cardiac events were 47%, 80% and 19%, respectively. Among patients were who ruled out for myocardial infarction, cTnI was elevated in 26% who had major cardiac complications compared with 5% for CK-MB; the positive predictive value for an abnormal cTnI result was 8%. Elevated cTnI in the presence of ischemia on the electrocardiogram was associated with an adjusted odds ratio of 1.8 (95% confidence interval 1.1 to 2.9) for major cardiac events within 72 h. Among patients without a myocardial infarction or unstable angina, cTnI was not an independent correlate of complications. CONCLUSIONS: In patients presenting to the ED with acute chest pain, cTnI was an independent predictor of major cardiac events, However, the positive predictive value of an abnormal assay result was not high in this heterogeneous cohort.

Adult↗
PubMed1998

A new casemix adjustment index for hospital mortality among patients with congestive heart failure.

OBJECTIVES: Comparative analysis of hospital outcomes requires reliable adjustment for casemix. Although congestive heart failure is one of the most common indications for hospitalization, congestive heart failure casemix adjustment has not been widely studied. The purposes of this study were (1) to describe and validate a new congestive heart failure-specific casemix adjustment index to predict in-hospital mortality and (2) to compare its performance to the Charlson comorbidity index. METHODS: Data from all 4,608 admissions to the Massachusetts General Hospital from January 1990 to July 1996 with a principal ICD-9-CM discharge diagnosis of congestive heart failure were evaluated. Massachusetts General Hospital patients were randomly divided in a derivation and a validation set. By logistic regression, odds ratios for in-hospital death were computed and weights were assigned to construct a new predictive index in the derivation set. The performance of the index was tested in an internal Massachusetts General Hospital validation set and in a non-Massachusetts General Hospital external validation set incorporating data from all 1995 New York state hospital discharges with a primary discharge diagnosis of congestive heart failure. RESULTS: Overall in-hospital mortality was 6.4%. Based on the new index, patients were assigned to six categories with incrementally increasing hospital mortality rates ranging from 0.5% to 31%. By logistic regression, "c" statistics of the congestive heart failure-specific index (0.83 and 0.78, derivation and validation set) were significantly superior to the Charlson index (0.66). Similar incrementally increasing hospital mortality rates were observed in the New York database with the congestive heart failure-specific index ("c" statistics 0.75). CONCLUSION: In an administrative database, this congestive heart failure-specific index may be a more adequate casemix adjustment tool to predict hospital mortality in patients hospitalized for congestive heart failure.

Aged↗
PubMed1997

Frontiers in Internal Medicine.

Clinical research in Internal Medicine has provided many scientific advances during the past few years. However, the newly generated information overrides the time available to read all of the medical literature regarding advances in Internal Medicine. The goal of this review is to summarize some of the most relevant improvements in clinical practice published over the last few years. From Cardiology to Pulmonology, the authors of this review expose in a succinct way what they and many of their peers consider to be the most transcendental information gathered from thousands of publications. The authors of this review article have attempted to avoid sensationalism by including facts instead of just simply optimistic preliminary findings that can mislead clinicians' decision making. The review is focused on information obtained through well-designed, prospective clinical trials and cohorts where the effectiveness of medical interventions and diagnostic procedures were tested.

Clinical Trials as Topic↗
PubMed1993

[Risk factors for non-communicable diseases in a metropolitan area in the south of Brazil. Prevalence and simultaneity].

Three-quarters of deaths in Rio Grande do Sul State, Brazil, are due to non-communicable diseases-cardiovascular diseases, alone, being responsible for 35% of them. To evaluate the prevalence of risk factors for these diseases, a household survey of 1,157 randomly sampled individuals between 15 and 64 years of age was undertaken in 1986 and 1987 in census tracts of 4 areas of the city of Porto Alegre. The age- and sex-adjusted prevalence of smoking was 40%, hypertension 14%, obesity 18%, overall sedentary life-style 47%, and excessive alcohol consumption 7%. Thirty-nine percent of the sample presented two or more of these five risk factors, and only 22% of men and 21% of women had none of them. The high frequencies and simultaneous presence of these risk factors indicate their importance for programs aimed at the prevention of non-communicable diseases and the promotion of adult health.

Adolescent↗
PubMed1993

Validity of self-reported weight--a study of urban Brazilian adults.

In order to evaluate the validity of self-reported weight for use in obesity prevalence surveys, self-reported weight was compared to measured weight for 659 adults living in the Porto Alegre county, RS Brazil in 1986-87, both weights being obtained by a technician in the individual's home on the same visit. The mean difference between self-reported and measured weight was small (-0.06 +/- 3.16 kg; mean +/- standard deviation), and the correlation between reported and measured weight was high (r = 0.97). Sixty-two percent of participants reported their weight with an error of < 2 kg, 87% with an error of < 4 kg, and 95% with an error of < 6 kg. Underweight individuals overestimated their weight, while obese individuals underestimated theirs (p < 0.05). Men tended to overestimate their weight and women underestimate theirs, this difference between sexes being statistically significant (p = 0.04). The overall prevalence of underweight (body mass index < 20) by reported weight was 11%, by measured weight 13%; the overall prevalence of obesity (body mass index > or = 30) by reported weight was 10%, by measured weight 11%. Thus, the validity of reported weight is acceptable for surveys of the prevalence of ponderosity in similar settings.

Adolescent↗
PubMed1993

Socioeconomic distribution of noncommunicable disease risk factors in urban Brazil: the case of Pôrto Alegre.

The study reported here sought to assess the degree to which the prevalences of five risk factors for noncommunicable diseases--hypertension, smoking, obesity, sedentary lifestyle, and excessive alcohol consumption--varied individually and in combination for urban Brazilians with differing socioeconomic status in terms of educational achievement, income, and social class. For this purpose, 1986-1987 data from a cross-sectional household survey of 1,157 randomly selected adults 15-64 years of age residing in the major Brazilian city of Pôrto Alegre were analyzed. In general, it was found that less privileged socioeconomic situations tended to be associated with higher risk factor prevalences. However, this was not the case for obesity and sedentary lifestyle among men, and may not have been the case with respect to hypertension among women. When the effects of education, income, and social class were considered simultaneously, higher risk factor prevalences were most strongly associated with low educational attainment. Important exceptions to this rule were found for smoking among women and excessive alcohol consumption among men, where higher risk factor prevalences were most associated with social class. Once the effects of education and social class were accounted for, low income generally tended to be associated with lower prevalences of the risk factors studied.

Adolescent↗
PubMed1992

[The pattern of the clinical use of digitalis. The need for a reassessment].

PURPOSE: To evaluate the pattern of utilization of digitalis in an academic hospital. METHODS: Clinical files of all patients admitted in medical wards at the Hospital de Clínicas de Porto Alegre were studied. Data were collected during five different days, three in the winter and two in the summer, keeping an interval of at least two weeks between each data collection. Heart failure diagnosis was evaluated objectively by means of a score proposed by Carlson et al. RESULTS: From a total number of 881 patients, 114 (13%) were receiving digoxin. Mean age was 66 +/- 13 years and 47% were males. Considering the patients who were taking digoxin, 32% presented scores compatible with definite or possible heart failure; 26% had atrial flutter or fibrillation; 18% had heart failure and supraventricular tachyarrhythmias; and in 24% no clear indications were found according to our criteria. Previous use of digoxin was found in 85% of the patients and 32% were withdrawn during the hospitalization. Considering just the patients who had no reason for using digoxin, only 44% had the drug withdrawn. CONCLUSION: According to current criteria, many hospitalized patients receive digoxin without a definite indication. These data suggest that reassessment of the use of digitalis should be incorporated into clinical practice.

Aged↗
PubMedDate not supplied

[Maternal knowledge on breastfeeding and related factors].

The influence of maternal knowledge about breastfeeding on the initiation and duration of lactation has been described. The present study evaluated the maternal knowledge about breastfeeding and its relationship with prenatal and postnatal orientation and prevalence of breastfeeding at 3 months. A cross-sectional study was designed involving 100 mothers of first-born babies between 6 and 12 months old receiving medical care in the Hospital de Clínicas de Porto Alegre. The mothers answered a standardized questionnaire containing 14 questions to test knowledge on breastfeeding. The majority of mothers (62%) could not answer correctly half of the questions. Those more educated, who received prenatal orientation about breastfeeding and who had at least 5 prenatal visits had better knowledge. On the other hand, mothers who received postnatal orientation did not present a better knowledge. Prevalence of breastfeeding at 3 months was not related to maternal knowledge on the subject. The maternal knowledge about many aspects of breastfeeding was low. Postnatal orientation did not increase this knowledge. On the other hand, prenatal orientation had a positive impact on maternal knowledge about breastfeeding. Nonetheless this increase in knowledge was not sufficient to interfere with the prevalence of early interruption of breastfeeding.

English Abstract↗
PubMedDate not supplied

[High mortality rates among Brazilian adult populations--an international comparison].

Adult disease in an increasingly important public health problem in Brazil. In order to compare adult mortality in Brazil to that in other countries, age-adjusted coefficients for adults aged 30-69 of the States of São Paulo and Rio Grande do Sul and of the city of Fortaleza (Ceará State) are compared to those of similarly aged adults in a series of 33, principally European, countries. The Brazilian population coefficients for overall, cerebrovascular and cardiovascular mortality are among the highest of the series; those for ischemic heart disease occupy median positions. These comparisons illustrate the precarious state of adult health in Brazil and, given the growing possibilities of preventing cardiovascular and other non-communicable diseases, help demonstrate the need for preventive programs in Brazil aimed at the major common and lethal diseases of the productive years of life.

Adult↗
PubMedDate not supplied

[Acute myocardial infarction in the thrombolytic era: high mortality in elderly patients].

UNLABELLED: Patients with acute myocardial infarction (AMI) admitted to a general hospital are very different from those reported in large multicenter trials. PURPOSE: To evaluate the in-hospital mortality in patients with AMI admitted to a general hospital in the thrombolytic era, and to identify factors associated with poor prognosis. METHODS: 113 consecutive patients admitted with AMI in one year at the Hospital de Clínicas of Porto Alegre were studied. Several clinical and laboratory variables related to higher risk were evaluated. According to the hospital routine, 47% of the patients received thrombolytic therapy, and the effects and complications of its use were studied. RESULTS: In-hospital mortality was 19.5%. By univariate analysis, age, female gender and peak creatinephosphokinase level were significantly associated with early mortality. By multiple logistic regression analysis, advanced age was the only predictive variable, even after adjusting for other baseline risk factors. In patients older than 70 years, in-hospital mortality was 41% versus only 8.1% in the younger group. There was no difference in survival with the presence of others factors such as previous myocardial infarction, use of thrombolytic therapy, heart failure, infarcted area, diabetes, and systemic hypertension. Among patients who received thrombolytic therapy, an elevated number of adverse effects was observed, and in 9.4% of the cases the complications were serious. CONCLUSION: The high in-hospital mortality after AMI in a general hospital is associated with the patients' advanced age. In spite of recent therapeutic advances in the treatment of AMI, older patients have not obtained a comparable benefit as that achieved by the younger group.

Adult↗