Uncovering the impact of COVID-19 on the place of death of cancer patients in South America

The COVID-19 pandemic has significantly impacted healthcare systems worldwide, especially on the management of chronic diseases such as cancer. This study explores the effects of COVID-19 on cancer mortality trends in Brazil, Chile, and Peru. The monthly age-standardized mortality rates in different places of death (hospital/clinic or home) were estimated using vital statistics and death certificate databases. An interrupted time series analysis was performed for each country, using the date of lockdown implementation as the intervention point. Overall cancer mortality rates reduced after the implementation of pandemic restrictions, with a significant decrease in Brazil. In total, 75.3%, 55.4%, and 45.7% of deaths in Brazil, Peru, and Chile, respectively, occurred in hospitals. After lockdowns were implemented, at-home deaths increased in all countries, and in-hospital deaths correspondingly decreased only in Chile. Our results suggest that COVID-19 has significantly affected rates of cancer mortality and place of death in Latin America.

Occupation as a measure of life course socioeconomic position and the risk of oral cancers in India

OBJECTIVES

Evidence suggests that different indicators of socioeconomic position (SEP) contribute to oral cancer risk. Occupational status, as a measure of SEP, may be able to capture aspects of social hierarchy in societies in which employment is highly correlated with other social structures such as caste systems. Often in such societies, the life course of an individual is also influenced by this hierarchy. However, the influence of life course occupational status on the risk of oral cancer is not well understood. This study aims to identify the life course model that is best supported by the data using life course SEP-as represented by occupation-on oral cancer risk in a population in the South of India.

METHODS

Data from the HeNCe Life study, Indian site were used. Incident oral cancer cases (N = 350) were recruited from two major referral hospitals in Kozhikode, Kerala, South India, from 2008 to 2012. Controls (N = 371), frequency-matched by age (5 years) and sex were recruited from the outpatient clinics at the same hospitals as the cases. Life grid-based structured interviews collected information on an array of exposures throughout the life course of the participant. Occupation was coded with the 1988 International Standard Classification of Occupations, transformed to the simplified European Socioeconomic Classification, and further dichotomized into advantageous and disadvantageous SEP at three different life periods (childhood, early adulthood and late adulthood). The analysis was conducted using the Bayesian relevant life course exposure model with a Dirichlet noninformative prior and a weakly informative Cauchy prior to the overall lifetime effect and confounders.

RESULTS

Participants in disadvantaged SEP throughout their life had 3.6 times higher risk of oral cancer than those in advantaged SEP (OR = 3.6; 95% CrI = 1.6-7.2), after adjusting for potential confounders. While the crude and sex- and age-adjusted models showed a clear childhood sensitive period for this risk, the model further adjusted for behavioural factors could not distinguish the specific life course period best explained by data.

CONCLUSION

Occupation status alone could provide a similar overarching risk estimate for oral cancer to those obtained from more complex measures of SEP.

Structural determinants explain caries differences among preschool children in Chile's Metropolitan Region

OBJECTIVE

To estimate the association between Social Determinants of Health (structural and intermediate) and caries indicators in Chile's Metropolitan Region preschool children.

METHODS

A multilevel cross-sectional study of Social Determinants of Health (SDH) and caries in children aged 1 to 6 years in Chile's Metropolitan Region was conducted in 2014-2015, with three levels: district, school and child. Caries were assessed by the dmft-index and the prevalence of untreated caries. The structural determinants analyzed were Community Human Development Index (CHDI), urban/rural location, school type, caregiver's education and family income. Poisson multilevel regression models were fit.

RESULTS

The sample size was 2,275 children from 40 schools in 13 districts. While the highest CHDI district had an untreated caries prevalence of 17.1% (12.3-22.7%), in the most disadvantaged district it was 53.9% (95% CI 46.0-61.6%). As family income increased, the probability of untreated caries prevalence decreased (PR = 0.9 95% CI 0.8-1.0). Rural districts had an average dmft-index of 7.3 (95% CI 7.2-7.4), while in urban districts, it was 4.4 (95% CI 4.3-4.5). Higher probabilities of untreated caries prevalence (PR = 3.0 95% CI 2.3-3.9) were observed in rural children. Greater probabilities of untreated caries prevalence (PR = 1.3 95% CI 1.1-1.6) and prevalence of caries experience (PR = 1.3 95% CI 1.1-1.5) were observed in children whose caregivers had a secondary educational level.

CONCLUSIONS

A strong association was observed between the social determinants of health, specifically the structural ones, and the caries indicators studied in children of the Metropolitan Region of Chile. There were notable differences in caries between districts according to social advantage. Rurality and caregiver's education were the most consistent predictors.

Life Course Tobacco Smoking and Risk of HPV-Negative Squamous Cell Carcinomas of Oral Cavity in Two Countries

Background

Tobacco smoking remains one of the major risk factors for oral cavity cancers (OCC), a subgroup of head and neck cancer (HNC) less attributed to human papillomavirus (HPV) infection. Although a strong dose-dependent association between tobacco smoking and OCC exists, several important questions on the age-dependent effects of this habit remain unanswered. We investigated which life course hypothesis best describes the association between tobacco smoking and HPV-negative (HPV−ve) OCC in Canada and India.

Methods

We used data from the HeNCe Life study, a hospital-based case-control study conducted in Canada and India, using similar protocols. Cases were newly diagnosed subjects with primary squamous cell carcinomas of the head and neck region. Control subjects were patients with non-cancer selected from various outpatient clinics in a hospital located in the same catchment area as the cases and frequency-matched to cases according to age and sex. We collected information on an array of life course exposures using a structured questionnaire with the help of a life grid. Tobacco exposure (pack-years) during three life periods (≤ 30, 31−50, and >50 years of age) was calculated from the entire life course history of smoking. We used CDx brushes to collect oral exfoliated cells. Alpha HPV DNA detection and genotyping were performed for 36 HPV genotypes using the linear array. Participants who tested positive for HPV were excluded from the analysis. We used the Bayesian relevant life course exposure model (BRLM) to identify the life course hypothesis that best described the relationship between tobacco smoking and HPV−ve OCC.

Results

We show evidence for a late-life sensitive period (>50 years of age) for tobacco smoking in relation to the risk of HPV−ve OCC in both Canada and India. An increase of 1 pack-year of tobacco smoking increased the risk of OCC by ~3% in both countries.

Conclusion

Our findings from the Canadian and Indian data suggest that smoking tobacco after 50 years of age may carry a higher risk of developing oral cancer than earlier in life. Further studies are warranted to confirm the results.

Health literacy and adherence to treatment in different districts in Chile

The relationship between health literacy and adherence has been described in medical literature, especially for patients with non-communicable diseases (NCDs). However, the relevance that an individual's local context can have has not been considered. This study aimed to examine the association of both concepts at a population level and estimate the correlation between health literacy and adherence to pharmacological treatment in adults from 14 districts in different regions in Chile. A cross-sectional study was carried out in 14 districts from 3 different regions of Chile. Sampling was carried out by volunteers. Three questionnaires were applied: sociodemographic; Morisky-Green-Levine (MMAS-4) and the Short Assessment of Health Literacy for Spanish Adults test (SAHLSA-50). Data were analyzed descriptively, and a Multilevel Poisson Regression model was fitted to evaluate the relationship between health literacy and adherence to pharmacological treatment, considering the districts as fixed intercepts. A total of 1,336 persons were surveyed; 811 self-reported as having at least 1 NCD. A 83.4% had adequate literacy and 37.1% were adherent to pharmacological treatment, regardless of their health literacy. A 3.6% (variance partition coefficient = 0.036) correlation of adherence to treatment was observed in respondents living in the same district. Those with inadequate health literacy had a 12% greater prevalence of being non-adherent (prevalence ratio 1.12; IC 95% 0.87 - 1.47) when adjusting for individual variables. These results could suggest that the individual's local context does not influence the relation of functional health literacy and adherence to pharmacological treatment in populations with basic and intermediate levels of education. We suggest further studies in this matter.

[Diagnostic properties of case definitions of suspected COVID-19 in Chile, 2020Características diagnósticas das definições de caso suspeito de COVID-19 no Chile, 2020]

Objective

Compare the diagnostic properties of five case definitions of suspected COVID-19 that were used or proposed in Chile during the first eight months of the pandemic.

Methods

An analysis was done of the diagnostic properties (sensitivity, specificity, and positive and negative predictive values) of three case definitions of suspected COVID-19 used in Chile between March and October 2020, as well as two alternative proposed definitions. The sample was 2,019 people with known results for the polymerase chain reaction (PCR) test for SARS-CoV-2. Stepwise logistic regression was used to develop criterion 5, optimizing sensitivity and specificity values. Multifactor logistic regression was used to explore the association between demographic variables, symptoms and signs, and PCR positivity. Different positivity scenarios were analyzed and ROC curves were compared.

Results

The presence of anosmia (OR = 8.00; CI95%: 5.34-11.99), fever (OR = 2.15; CI95%: 1.28-3.59), and having been in close contact with a person sick with COVID-19 (OR = 2.89; CI95%: 2.16-3.87) were associated with a positive PCR result. According to the analysis of the ROC curve, criterion 5 had the highest capacity for discrimination, although there were no significant differences with the other four criteria.

Conclusions

Criterion 5-based on anosmia, close contact with people with COVID-19, and fever as sufficient unique elements-was the most sensitive in identifying suspected cases of COVID-19, a key aspect in controlling the spread of the pandemic.

A Molecular Stratification of Chilean Gastric Cancer Patients with Potential Clinical Applicability

Gastric cancer (GC) is a complex and heterogeneous disease. In recent decades, The Cancer Genome Atlas (TCGA) and the Asian Cancer Research Group (ACRG) defined GC molecular subtypes. Unfortunately, these systems require high-cost and complex techniques and consequently their impact in the clinic has remained limited. Additionally, most of these studies are based on European, Asian, or North American GC cohorts. Herein, we report a molecular classification of Chilean GC patients into five subtypes, based on immunohistochemical (IHC) and in situ hybridization (ISH) methods. These were Epstein-Barr virus positive (EBV+), mismatch repair-deficient (MMR-D), epithelial to mesenchymal transition (EMT)-like, and accumulated (p53+) or undetected p53 (p53-). Given its lower costs this system has the potential for clinical applicability. Our results confirm relevant molecular alterations previously reported by TCGA and ACRG. We confirm EBV+ and MMR-D patients had the best prognosis and could be candidates for immunotherapy. Conversely, EMT-like displayed the poorest prognosis; our data suggest FGFR2 or KRAS could serve as potential actionable targets for these patients. Finally, we propose a low-cost step-by-step stratification system for GC patients. To the best of our knowledge, this is the first Latin American report on a molecular classification for GC. Pending further validation, this stratification system could be implemented into the routine clinic.

Retrospective Analysis of Chilean and Mexican GI Stromal Tumor Registries: A Tale of Two Latin American Realities

PURPOSE

Like other malignancies, GI stromal tumors (GIST) are highly heterogeneous. This not only applies to histologic features and malignant potential, but also to geographic incidence rates. Several studies have reported GIST incidence and prevalence in Europe and North America. In contrast, GIST incidence rates in South America are largely unknown, and only a few studies have reported GIST prevalence in Latin America.

PATIENTS AND METHODS

Our study was part of a collaborative effort between Chile and Mexico, called Salud con Datos. We sought to determine GIST prevalence and patients' clinical characteristics, including survival rates, through retrospective analysis.

RESULTS

Overall, 624 patients were included in our study. Our results found significant differences between Mexican and Chilean registries, such as stage at diagnosis, primary tumor location, CD117-positive immunohistochemistry status, mitotic index, and tumor size. Overall survival (OS) times for Chilean and Mexican patients with GIST were 134 and 156 months, respectively. No statistically significant differences in OS were detected by sex, age, stage at diagnosis, or recurrence status in both cohorts. As expected, patients categorized as being at high risk of recurrence displayed a trend toward poorer progression-free survival in both registries.

CONCLUSION

To the best of our knowledge, this is the largest report from Latin America assessing the prevalence, clinical characteristics, postsurgery risk of recurrence, and outcomes of patients with GIST. Our data confirm surgery as the standard treatment of localized disease and confirm a poorer prognosis in patients with regional or distant disease. Finally, observed differences between registries could be a result of registration bias.

Quantitative Bias Analysis of misclassification in case-control studies: an example with Human Papillomavirus and Oropharyngeal Cancer

OBJECTIVE

Laprise et al. (2019) observed a positive association between oral sex practices and oropharyngeal cancers (OPC) among HPV-negative individuals. Because oral HPV infections are likely to be transmitted through oral sex, these results are counterintuitive. We revisit Laprise et. al's analysis with the objective of estimating the impact of misclassification of HPV infection on the association between oral sex practices and OPC.

METHODS

Data were drawn from the Head and Neck Cancer (HeNCe) Life study, a hospital-based case control study of head and neck cancer with frequency-matched controls by age and sex from 4 major referral hospitals in Montreal, Canada. We included only OPC cases (n = 188) and controls (n = 429) and used predictive value weighting, under differential and non-differential scenarios, to evaluate the misclassification. Subsequently, we used logistic regression and 95% confidence intervals to estimate the association between oral sex practice and OPC among HPV-negative individuals.

RESULTS

Our results showed that the previously reported association between oral sex practices and OPC among HPV-negative individuals was attenuated or nullified both under differential and non-differential scenarios.

CONCLUSION

The association between oral sex practice and OPC could be explained by biases in the data (e.g., HPV mediator misclassification). Our results highlight the need for widespread adoption of Quantitative Bias Analysis in oral health research.

[Spatial autocorrelation of breast cancer mortality in the Metropolitan Region, Chile: an ecological study]

Introduction

Breast cancer is the most common malignancy in women worldwide and Chile, being the leading cause of female cancer death. A wide variation in mortality has been reported, with geographic clusters of higher risk.

Objective

To spatially analyze mortality from breast cancer in women in the Metropolitan Region in 2015.

Methods

Ecological study of location. We used death records in 2015 (C50 according to ICD10) and population projections of the Statistics Institute to estimate mortality rates. We calculated crude breast cancer mortality rates and standardized mortality ratios and performed a spatial epidemiological analysis of breast cancer mortality in women, estimating the global and local Moran I index to assess spatial autocorrelation. We present the results in maps according to the 2016 pre-census cartography.

Results

There were 622 deaths from breast cancer in the Metropolitan Region in 2015. The mean age was 66 years (SD: 15.5). 92.4% of deaths were registered in urban or central areas. However, the highest mortality rates were observed in peripherical districts. No global spatial autocorrelation was observed in the region (Morans I 0.007 p = 0.134). However, at the local level, four districts differ significantly from their neighbors.

Conclusions

The risk of dying from breast cancer in the Metropolitan Region of Chile is concentrated in women from peripherical communes. Four districts in the region present different risks from their neighboring districts. It is necessary to investigate local realities to prevent deaths from this pathology.

Lipoprotein lipase and lipogenic enzyme activities in adipose tissue from rats fed different lipid sources

This work was designed to study the effect of different lipid sources on the activities of lipoprotein lipase and lipogenic enzymes in adipose tissue from rats fed ad libitum or energy-controlled diets. Male Wistar rats were fed diets containing 40% of energy as fat (olive oil, sunflower oil, palm oil or beef tallow), for 4 wk. Under ad libitum feeding no differences were found among dietary fat groups in final body weight, adipose tissue weights and total body fat. Under energy-controlled feeding, despite isoenergetic intake, rats fed the beef tallow diet gained significantly less weight than rats fed the other three diets. Beef tallow fed rats showed the lowest values for adipose tissue weights and total body fat. When rats had free access to food no effect of dietary lipid source on lipogenic enzyme activities was found. In contrast, under energy-controlled feeding rats fed the beef tallow diet showed significantly higher activities of glucose-6-phosphate dehydrogenase and fatty acid synthase than rats fed the other three diets. Heparin-releasable lipoprotein lipase activity in perirenal and subcutaneous adipose tissues was not different among rats fed olive oil, safflower oil, palm oil or beef tallow. When comparing both adipose tissue anatomical locations, significantly higher activities were found in subcutaneous than in perirenal fat pad independently of dietary fat. In conclusion, under our experimental protocol, lipogenesis in rat adipose tissue does not seem to be affected by dietary fat type.

Differential effects of diets that provide different lipid sources on hepatic lipogenic activities in rats under ad libitum or restricted feeding

This work was designed to study the effect of different lipid sources on hepatic lipogenic enzyme activity in rats fed ad libitum or energy-controlled diets. Male Wistar rats were fed diets containing 40% of energy as fat (olive oil, sunflower oil, palm oil, or beef tallow) for 4 wk. In experiment 1 rats had free access to food, and in experiment 2 rats were fed a controlled amount of food. In both experiments, rats fed the olive oil diets had higher activities of glucose-6-phosphate dehydrogenase, malic enzyme, fatty acid synthase, and acetyl-CoA carboxylase (P < 0.05) than rats fed the other fats. It is unlikely that this effect could be attributed to the stimulation by insulin or triiodothyronine because serum values did not differ among the groups. Enzymatic activities were positively and significantly correlated with liver triacylglycerol content, but not with serum triacylglycerol levels. No interaction between lipid source and feeding protocol was found. Oleic acid and components in olive oil other than fatty acids, such as phytosterols, may account for the effects of dietary fat on lipogenic enzyme activity.

Monoclonal antibodies to human apolipoproteins: application to the study of high density lipoprotein subpopulations

We produced, selected and cloned hybridomas that secrete monoclonal antibodies against human apolipoprotein (apo) A-I. All of the antibodies corresponded to the IgG(1) subclass and were named 1C11, 2B4, 2C10, 7C5, 8A4 and 8A5. The antibodies were characterized by their reactivity with whole lipoproteins, apolipoproteins, synthetic peptides and fragments generated by cleavage of the apo A-I. Three of the monoclonal antibodies studied (2B4, 2C10 and 7C5) were similarly inhibited by an amino-terminal peptide (amino acid sequence 1-20) of apo A-I, whereas antibodies 1C11, 8A4 and 8A5 had no reaction. Other results show that monoclonal antibody 1C11 recognizes an epitope located between amino acids 135-148. We evaluated the monoclonal antibody 8A4 against different HDL subpopulations by competitive displacement analysis and it showed a similar reactivity with the HDL particles: LpA-I and LpA-I:A-II. This antibody was used to standardize a sandwich ELISA to quantitate LpA-I in plasma. We conclude that these monoclonal antibodies are relevant for the study of apo A-I epitope expression and for quantitating apo A-I containing lipoparticles.

[Lipoprotein particles LpA-I, LpA-I: A-II and LpB in coronary artery disease]

BACKGROUND

High density lipoproteins are an heterogeneous population of particles. Two main subpopulations have been identified, one contains Apo A-I and Apo A-II and is denominated LpA-I:A-II and another one contains only Apo A-I and is denominated LpA-I.

AIM

To measure the concentrations of these particles in patients with stable coronary artery disease.

PATIENTS AND METHODS

Serum lipids, A-I and B apolipoproteins, LpA-I, LpA-I:A-II and LpB particles were measured in 73 men aged 33 to 82 years with angiographically documented coronary artery disease (CAD) and 33 control subjects aged 39 to 76 years. LpA-I, LpA-I:A-II and LpB were measured by a noncompetitive enzyme linked immunoassay using previously characterized monoclonal antibodies against ApoA-I, ApoA-II and apoB.

RESULTS

Patients with CAD had significantly higher mean levels of LDL cholesterol than the control group (p = 0.038). The mean concentration of LpA-I particles in patients with CAD was significantly lower (p = 0.031) than in control subjects, while the concentration of LpA-I:A-II particles was significantly higher (p = 0.016). The percentage of coronary stenosis correlated negatively with LpA-I and positively with LpA-I:A-II. The best relative risk (RR) indicator in these patients was LDL-cholesterol. The relative risk increases 2.5 fold when LpA-I falls below the cut-off level. Likewise, the relative risk increases 3-fold when LpA-I:A-II raises over the cut-off level.

CONCLUSIONS

Our findings indicate that the quantification of LpA-I and LpA-I:A-II particles might allow a more accurate evaluation of the CAD risk than HDL cholesterol. LpA-I might represent the antiatherogenic fraction of HDL.

In vitro effect of estradiol, progesterone, testosterone, and of combined estradiol/progestins on low density lipoprotein (LDL) oxidation in postmenopausal women

OBJECTIVE

One of the mechanisms currently proposed to explain the cardioprotective effect of hormone replacement therapy (HRT) is the antioxidative property of estrogens. Considering that HRT involves the administration of an estrogen, usually combined with a progestin and sometimes with an androgen, we investigated the following in vitro: (1) the effect of estradiol, progesterone, and testosterone on the oxidation of low density lipoprotein; (2) the possible pro-oxidative effect of progesterone and testosterone on native low density lipoprotein; and (3) the possible modification of the antioxidant effect of estradiol on low density lipoprotein induced by progestins.

DESIGN

Low density lipoprotein was isolated from blood samples obtained from 20 untreated postmenopausal women and divided in multiple aliquots, each containing 0.5 mg LDL protein. In Protocol 1 (n = 10) different doses of estradiol, progesterone, and testosterone ranging from 0 to 26 micrograms/ml were tested inducing oxidation with 15 microM copper sulfate. In Protocol 2 (n = 6) we studied the rate of oxidation of low density lipoprotein incubated with progesterone or testosterone without any oxidative induction. In Protocol 3 (n = 10) we studied the concomitant effect of 15 microM estradiol with four separate progestins (progesterone, medroxyprogesterone acetate, norethindrone, and norgestrel) in different doses (0, 5, 15, and 50 microM). After incubation for 4 h at 37 degrees C, malonaldehyde was measured as a marker of low density lipoprotein oxidation. The results were expressed in mean +/- SD.

RESULTS

Protocol 1: Estradiol induced a dose-dependent decrease in malonaldehyde generation, from a baseline of 61.8 +/- 30.2 nmol/mg protein to 11.6 +/- 7.1 nmol/mg protein at the highest dose of estradiol tested (p < 0.0001). Progesterone or testosterone did not modify malonaldehyde generation. Protocol 2: Progesterone and testosterone did not show pro-oxidative action. Protocol 3: Estradiol 15 microM alone induced a 35% decrease in malonaldehyde generation, from a baseline of 75.4 +/- 25.4 to 49.3 +/- 18.8 nmol/mg protein (p < 0.0001). Norgestrel and norethindrone did not modify the antioxidant effect of estradiol (p > 0.05). Progesterone and medroxyprogesterone acetate induced a further reduction of malonaldehyde concentration to 37.2 +/- 20.8 and 38.6 +/- 18.2 nmol/mg protein, only at the highest dose tested (p < 0.02 and p < 0.01, respectively).

CONCLUSIONS

Our results demonstrate that, in contrast with the potent antioxidant effect of estradiol, progesterone and testosterone did not show any pro- or antioxidant effect on low density lipoprotein in vitro. Furthermore, progestins did not counteract the antioxidant effect of estradiol in vitro.

[Immune response against modified low-density lipoproteins in patients with non-insulin-dependent diabetes mellitus]

BACKGROUND

Diabetes mellitus is a risk factor for atherosclerosis. Low density lipoproteins are considered a key factor in the formation of atheroma and the immune system has an important contribution to this process.

AIM

To quantify the immune response against modified low density lipoproteins in patients with non insulin dependent diabetes mellitus.

MATERIAL AND METHODS

LDLs obtained from blood of healthy subjects, were glycated or altered with malondialdehyde and used as antigens. Serum autoantibodies against these LDLs were measured by ELISA in 22 patients with non insulin dependent diabetes mellitus aged 46 to 67 years old and 13 healthy controls aged 41 to 65 years old. Basal and LDL stimulated tumor necrosis factor a production in vitro, by peripheral leukocytes of diabetics and controls was also measured.

RESULTS

The ratio of glycated LDL/native LDL antibodies was higher in diabetics than in controls (9.37 +/- 2.72 and 0.41 +/- 0.11 respectively p < 0.05) and the ratio of MDA modified LDL/native LDL antibodies was not significantly different (8.64 +/- 3.83 and 2.14 +/- 1.26 respectively, NS). Tumor necrosis or production by leukocytes was higher in diabetics than in controls in basal conditions (53.3 +/- 15.3 and 26.9 +/- 14.7 arbitrary units (a.u.) respectively), when stimulated with native LDL (46.5 +/- 5 and 24.3 +/- 9.4 a.u. respectively), when stimulated with malondialdehyde modified LDL (50 +/- 16.2 and 24.4 +/- 7.7 a.u. respectively) or when stimulated with glycated LDL (38.3 +/- 8.8 and 14.4 +/- 7.5 a.u. respectively).

CONCLUSIONS

Diabetic patients have an enhanced immune response against low density lipoproteins, factor that could contribute to the accelerated atherogenesis of this disease.

[Effects of low doses of aprotinin in heart surgery]

OBJECTIVES

To study the effect of aprotinin (Trasylol) administration on bleeding after surgery and on the need for blood transfusion in patients undergoing cardiopulmonary bypass with extracorporeal circulation (ECC).

PATIENTS AND METHODS

One hundred ten patients were studied prospectively, divided into two groups. In the aprotinin group (n = 80), the ECC pump was primed with 140 mg of aprotinin and followed with continuous intravenous perfusion at 70 mg/h from the start of ECC until the patient left the operating theater. The control group (n = 30) served as reference. The parameters compared were the hematocrit, number of platelets, prothrombin time and activated coagulation time, as well as drainage of blood through thoracic tubes at 3 and 24 h after surgery and the amount of blood transfused both during and after the procedure.

RESULTS

Blood loss was significantly lower in the aprotinin group as compared with the control group, both at 3 h (227 +/- 193 vs 380 +/- 169 ml; p < 0.05) and at 24 h (422 +/- 322 ml vs 736 +/- 342 ml; p < 0.05) after surgery. There was also a significant decrease in blood requirements in the aprotinin group (550 +/- 450 ml vs 872 +/- 747 ml; p < 0.05). There were no differences between the two groups for the other parameters studied.

CONCLUSIONS

Administration of aprotinin at low doses during surgery in patients undergoing cardiac surgery with ECC significantly reduces postoperative bleeding and the amount of blood transfused.

Prognostic implications of clinical, electrocardiographic and hemodynamic findings in chronic Chagas' disease

To evaluate the prognostic importance of 19 clinical, electrocardiographic and hemodynamic variables, 556 chronic chagasic patients were submitted to an extensive protocol, including left cineventriculogram and Holter monitoring, and followed for up to 15 years. The protagonist role of the magnitude of the myocardial compromise in the evolution of chagasic patients is underscored by our results, which indicated the independent prognostic value of an ejection fraction below 0.30 (P < 0.001), a heart rate higher than 89 beats/min (P < 0.01), grade IV functional capacity (P < 0.05), end systolic stress > 120 g/cm2 (P < 0.05), and end diastolic volume index > 200 ml/m2 (P < 0.05). When only patients with an ejection fraction over 0.29 were considered, variables with independent prognostic value were: the cardio-thoracic ratio (P < 0.01), functional capacity (P < 0.05) and heart rate (P < 0.05). Survival analysis demonstrated that the presence of complex (Lown III, IV) ventricular arrhythmias increased mortality significantly (P < 0.01) only in patients with an ejection fraction over 0.29. Therefore, preservation of myocardial function is the capital measure in the treatment of chronic chagasic patients.

[The anti-arrhythmia effect of carbamazepine in chagasic patients with advanced myocardial damage]

Oral administration of 600 mg/day of carbamazepine to 14 arrhythmic chagasic patients with advanced myocardial damage and no signs of congestive heart failure did not alter the frequency of ventricular extrasystoles, but reduced the total number of supraventricular ectopic beats in 7/14 patients and the episodes of complex ventricular arrhythmias in up to 43% of patients. This assessment was made from 24 hour continuous Holter recording during the course of this double-blind, placebo controlled, randomized crossover study. Serum levels of carbamazepine were also determined and found within therapeutic limits. Six patients complained of minor side effects. One patient presented with iatrogenic complete AV block, another case had proarrhythmic effect and one patient had to be withdrawn from the study because of gastric irritation. No instance of contractile depression was observed. Accordingly, carbamazepine is a therapeutic alternative for treatment of symptomatic complex ventricular or supraventricular arrhythmias in chronic chagasic patients without evidence of conduction system involvement or with intolerance to other antiarrhythmic drugs.

Thromboembolism in patients with pericardial valves in the absence of chronic anticoagulation: 12 years' experience

Between January 1977 and January 1989, 465 pericardial bioprostheses were implanted in 424 patients. The mean age of patients was 59.1 years (range 16-81 y.) At the time of surgery, 68% of the patients suffered from chronic atrial fibrillation. Mitral valve replacement was performed in 167 patients, aortic valve replacement in 216, multiple replacement in 40 (36 mitral and aortic, 3 mitral and tricuspid, and 1 mitral, aortic and tricuspid), and 1 pulmonary valve replacement. The different types of pericardial valve used were: Ionescu-Shiley 408, Mitral Medical 23, Bioflo 30, and Hancock 4. Hospital mortality was 10.1% with an attrition rate of 1.8 episodes per 100 patients/year. The 12-year actuarial survival rate was 65.1%. No patient underwent long-term anticoagulant treatment. The first 144 patients undergoing mitral and multiple valve replacements received temporary anticoagulation for the first 8 weeks after surgery. There was no valve thrombosis observed. Altogether 19 thromboembolic events (6 early and 13 late) were clinically documented. One patient died after an embolic event. The linearized rates of thromboembolism were 1.64 episodes per 100 patients/year for mitral and multiple valve replacements and 0.33 episodes per 100 patients/year for aortic valve replacement, with an overall rate of 1.0 episodes per 100 patients/year. Excluding early thromboembolism, the linearized rate was 1.02 episodes per 100 patients/year overall. The actuarial freedom from embolism was 92.4% overall, 88.2% for the mitral and multiple valve replacement group, and 97.6% for the aortic valve replacement group at a maximum follow-up of 12 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Duplication of the right atrioventricular orifice in a patient with common atrium and mitral cleft

The following case involved duplication of the right atrioventricular valve in a patient with a common atrium. The accessory orifice, formed by two fine leaflets, connected the right atrium with the right ventricular outflow tract and had no subvalvular apparatus. Successful surgical correction was accomplished under standard cardiopulmonary bypass.