The Latin American Multicenter Trial on psychosocial support during pregnancy: methodology and baseline comparability. Latin American Network for Perinatal and Reproductive Research (LANPER)

This article presents the methodology and baseline findings of a large multicenter trial involving four countries from Latin America (Argentina, Brazil, Cuba, and Mexico). The study was a randomized, controlled, single-masked trial to investigate the impact of social support during pregnancy on perinatal outcomes. Pregnant women with gestational ages between 15 and 22 weeks were screened in health facilities in the four countries. Those presenting with one or more risk factors for having a low-birthweight baby were invited to join the trial. A total of 2235 women--between 500 and 600 in each country--were randomized into an intervention (n = 1110) or a control (n = 1125) group. Both groups were comparable in terms of nearly all baseline variables. The intervention group received a minimum of four visits at home by a trained health worker who provided direct emotional support, health education, and an attempt to enhance the woman's social support network. Over 90% of all women were evaluated at 36 weeks of pregnancy and soon after delivery, and 85% at the 40th day postpartum. The outcomes under study included intrauterine growth retardation, gestational age, perinatal and maternal morbidity and mortality, labor interventions, psychological distress and characteristics of the social support network, among others. This trial showed that it was possible to select, screen, randomize, visit, and evaluate a large number of women in four Latin American countries using a standardized methodology.

Safety and anticoagulation effect of a low-dose combination of warfarin and aspirin in clinically stable coronary artery disease. Coumadin Aspirin Reinfarction (CARS) Pilot Study Group

The hypothesis that the combination of low-dose aspirin and warfarin therapy is more effective than aspirin alone in secondary prophylaxis after myocardial infarction is to be examined in the Coumadin Aspirin Reinfarction Study. This pilot study addressed the safety and anticoagulation effect of a fixed, low-dose combination in 114 patients (aged 64 +/- 8 years, 85% men) with stable coronary artery disease receiving 3 mg of warfarin plus 80 mg of aspirin daily for 8 weeks. The international normalized ratio (INR) was measured within 72 hours of initial therapy, and weekly. Of the 110 patients with evaluable INRs, 87 patients (79%) maintained the 3 + 80 mg combination, 19 (17%) had the dose reduced to 1 mg warfarin + 80 mg aspirin, and 4 (4%) discontinued therapy because of a confirmed INR of > or = 4.5. At steady state, patients had INRs of 1.48 +/- 0.41 (3 + 80 mg group) and 1.21 +/- 0.23 (1 + 80 mg group), and inter- and intra-patient variability (estimated by the mean of the between- and within-patient SDs at steady state) was 0.49 +/- 0.08 and 0.13 +/- 0.14, respectively. There was no apparent effect of age on INR distribution. Microscopic hematuria was the most frequent (20%) adverse clinical event, but was unrelated to the INR. Three patients required discontinuation of therapy because of bleeding events (persistent hematuria and epistaxis). A fixed low-dose combination of warfarin and aspirin results in a predictable and stable increase in the INR in a large proportion of patients with coronary artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Torsades de pointes ventricular tachycardia following right pneumonectomy: insights into the relation between right cardiac sympathetic nerve damage, QT intervals, and arrhythmias

Polymorphic ventricular tachycardia in association with prolongation of the QT interval on the surface electrocardiogram (ECG) has long been recognized as an important cause of life threatening arrhythmias that can occur with congenital or acquired abnormalities of cardiac repolarization. One hypothesis of the origin of these arrhythmias states that overactivity of the left-sided sympathetic or under activity of the right-sided sympathetic neural input to the heart leads to prolonged repolarization and ventricular arrhythmias. This hypothesis has led to the application of left cervicothoracic sympathetectomy for control of arrhythmias in congenital long QT syndromes. Although animal models have shown QT prolongation following right stellate ganglionic section or left stellate stimulation, spontaneous ventricular arrhythmias following stellate stimulation or block in man have not been demonstrated. We report the case of a patient with life threatening ventricular arrhythmias following surgical damage to the right cardiothoracic sympathetic nerves.

Importance of ST-segment depression as a determinant of ventricular premature complex frequency after thrombolysis for acute myocardial infarction. Tissue Plasminogen Activator: Toronto (TPAT) Study Group

Ventricular premature complexes (VPCs) after acute myocardial infarction (AMI) remain important determinants of survival in the post-thrombolytic era. The role of thrombolysis, left ventricular function, and Holter ST-segment depression in modulating VPC frequency is unclear. In a placebo-controlled, randomized study of tissue-type plasminogen activator (t-PA) in 103 patients with AMI (Tissue Plasminogen Activator: Toronto study), VPC frequency and ST depression on Holter monitoring (day 7), ejection fraction by radionuclide scan (day 9), and infarct artery patency and cross-sectional area on day 1 (n = 42) were assessed. After administering t-PA, VPC frequency was 10 +/- 58/hour (mean +/- SD), similar to that after placebo (23.5 +/- 91.7, p = NS). However, patients with ST depression had greater VPC frequency (56 +/- 140/hour) than those without it (1.3 +/- 2.6/hour, p = 0.05). Ejection fraction was negatively correlated with VPC frequency (r = -0.33, p < 0.001). By multivariate analysis, ejection fraction (F = 7.0, p < 0.01) and ST depression (F = 5.8, p < 0.02) were the only independent predictors of VPC frequency. In this placebo-controlled study, VPC frequency after AMI was not related to thrombolytic administration but was associated with ST depression and ejection fraction. This suggests that the underlying extent of both infarcted and ischemic myocardium is important in modulating ventricular arrhythmias after AMI.

Estimating maternal mortality in rural areas of Mexico: the application of an indirect demographic method

OBJECTIVE

To measure maternal mortality levels in rural areas of Mexico.

METHODS

In a cross-sectional study, a census of 13,378 households was carried out in the municipalities of Yecapixtla and Tlaltizapan, Morelos, Mexico. Information on 10,443 subjects from 12 to 49 years old was included in the analysis. An indirect method of measuring maternal mortality--the sisterhood method--was used to estimate maternal mortality. Information about the number of sisters of the interviewees who died due to maternal causes was collected in the census. With this information, estimates of maternal mortality related to a period of 10-12 years before the application of the census were obtained. An innovation to the original method was the calculation of a confidence interval for the estimated maternal mortality rate (MMR).

RESULTS

The MMR in this region was 18.68/10,000 live births (95% CI 15.79-21.58/10,000 live births). The average risk of dying due to maternal causes was 1 in 87 for women between 12 and 49 years of age.

CONCLUSIONS

The sisterhood method was effective for estimating maternal mortality in a small region, with no previous information about this indicator. The method proved to be useful for identifying a priority region for the implementation of maternal mortality reduction programs. Furthermore, the method was particularly convenient since it was applied as part of a multipurpose survey.

[The factors associated with hospital maternal death in the state of Morelos, Mexico]

The objective of this case-control study was to assess some risk factors related to hospital maternal mortality in the state of Morelos, Mexico. The cases were all maternal deaths which occurred in Morelos between 1989 and 1991 (n = 35), and the controls were women who presented the same complications and were taken care for at the same hospitals than the cases, but survived pregnancy and delivery (n = 35). The results showed that living with a partner is a protective factor (OR = 0.08), as well as using family planning methods (OR = 0.15). Not receiving care at the first place where it was requested was a risk factor (OR = 6.6). Maternal deaths had the same number of prenatal care visits than controls, but their first visit occurred, in average, one month later. The implications of the small sample size, characteristic of the studies on maternal mortality, are discussed at length. The results pinpoint the need to strengthen high-risk pregnancies screening programs through early prenatal care, and promote intersectorial strategies to provide care to pregnant women.

Frequency of transient reductions in left ventricular ejection fraction at rest in coronary artery disease

To determine the prevalence of decreases in left ventricular (LV) ejection fraction (EF) at rest in patients with coronary artery disease (CAD), including those with stable angina (n = 21), unstable angina (n = 13), and recent myocardial infarction (n = 11), continuous assessment of LV function for 162 +/- 136 minutes was performed using a new nuclear device. The results were compared with those of a group of normal subjects (n = 10) monitored for 80 +/- 28 minutes. Episodes of EF reduction of > 7% from baseline for a total duration of > 5% monitored time occurred in 0 of 10 normal subjects; episodes were more frequent in patients with stable angina (10 of 21, 48%; p = 0.01), with recent myocardial infarction (7 of 11, 64%; p = 0.004), and with unstable angina (11 of 13, 85%; p = 0.0001). The number of EF decreases per hour in patients after myocardial infarction (1.7 +/- 2.5 [SD]) and unstable angina (1.2 +/- 0.7) was significantly more frequent than in normal subjects (0.3 +/- 0.4), but was not different from that in patients with stable angina (0.8 +/- 1.0). The duration of the decrease in EF, expressed as minutes per hour of monitored time in normal subjects (0.7 +/- 1.0%), was significantly less than in patients with unstable angina (10 +/- 8%). Patients with stable angina (6 +/- 9%) and recent myocardial infarction (6 +/- 6%) were not significantly different from normal subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Does ambulatory monitoring contribute to exercise testing and myocardial perfusion scintigraphy in the prediction of the extent of coronary artery disease in stable angina?

The role of ambulatory myocardial ischemia detection, in addition to exercise testing and myocardial perfusion scintigraphy, in the prediction of the angiographic severity of coronary artery disease in patients with stable angina was examined. Ninety-seven patients underwent ambulatory electrocardiographic monitoring, exercise testing with scintigraphy, and coronary angiography. In addition to the number of diseased vessels involved, proximal arterial segment and coronary artery jeopardy scores were calculated to evaluate the extent of disease and amount of myocardium at risk. Thirty patients (31%) had 1.8 +/- 1.8 episodes/24 hours of ambulatory ischemia (94% of episodes were asymptomatic) and were similar to 67 without ambulatory ischemia in regard to clinical characteristics, left ventricular function and mean number of diseased vessels involved. Proximal arterial segment and coronary artery jeopardy scores were greater in: (1) 30 patients with versus 67 without ambulatory ischemia (3.3 +/- 1.8 vs 1.9 +/- 1.5 [p = 0.0002] and 6.6 +/- 3.6 vs 5.0 +/- 3.4 [p = 0.03], respectively); (2) 78 with versus 19 without a positive exercise test (2.6 +/- 1.8 vs 1.4 +/- 0.8 [p = 0.0001] and 6.1 +/- 3.5 vs 3.0 +/- 2.5 [p = 0.0003], respectively); and (3) 69 with versus 6 without a positive perfusion scan (2.4 +/- 1.8 vs 1.0 +/- 0 [p = 0.0008] and 5.5 +/- 3.6 vs 2.3 +/- 2.0 [p = 0.03], respectively). In multivariate analysis, ambulatory ischemia was the best predictor of the proximal segment score, whereas exercise testing and myocardial perfusion imaging were predictive of the coronary jeopardy score.

Myocardial alterations during hemodialysis: insights from new noninvasive technology

Eighteen patients with chronic renal failure had their cardiac status monitored during hemodialysis (HD). Ten studies were carried out using an ambulatory nuclear vest to assess ejection fraction (EF), heart rate (HR), relative end-systolic (ESV) and end-diastolic (EDV) volumes every 60 s. A total of 36 episodes of EF falls occurred in 9 patients, all asymptomatic. These EF falls were associated with a rise in ESV, while HR, BP, and EDV remained unchanged. The EF falls correlated best with the volume of ultrafiltrate removed. Ten patients had on-line ST-segment monitoring with sestamibi injection either at the time of ST depression (STD) or at the end of dialysis, if no STD occurred, in order to detect the presence of transient ischemia. Seven of ten patients had perfusion defects after dialysis, with STD occurring in 3 of 10 patients. Predialysis imaging was available in only 8 of 10 patients, and 6 of these patients had perfusion defects. Changes in perfusion defects were not significantly different in the 3 patients with STD compared with those without STD. EF falls and perfusion defects are common in HD patients even in the absence of known coronary artery disease; however, ST segment monitoring is not a sensitive tool for its detection. These changes in function and perfusion may represent myocardial ischemia and contribute to the high incidence of cardiovascular morbidity and mortality in this patient population.

[Psychosocial support in pregnancy as a strategy to promote the newborn's health]

In this project we developed a social support and health education intervention meant to answer whether or not a program of this kind, within the present medical system, can improve perinatal outcomes. A multicenter randomized controlled trial was conducted in four Latin American countries. In Mexico, the project was carried out in a third level obstetric hospital. Patients were screened between the 15th and 22nd week of gestation. Inclusion criteria were factors associated with high risk of low birthweight. A total of 620 women were recruited, randomized and followed up during pregnancy and up to the 40th day post partum. Women in the intervention group were visited four to six times during pregnancy, could use a telephone hot line and a consultation service. A poster and a pamphlet meant to reinforce health education were handed out in the first visit. A "guided tour" for women at the end of pregnancy was organized periodically. Outcomes were measured in both groups at the 36th week of gestation, post partum and 40 days after delivery. Neonatal outcomes were obtained by blind interviewers from the clinical records. Neither in the multicenter nor in the Mexican sample were we able to modify the incidence of low birthweight and prematurity. However, in Mexico we obtained positive effects on birthweight and gestational age in the whole sample and in some specific strata. These results strongly suggest the convenience of replicating the study in Mexico.

Humoral and cellular immunopathology of hepatic and cardiac hamster-into-rat xenograft rejection. Marked stimulation of IgM++bright/IgD+dull splenic B cells

Normal Lewis rat serum contains antibodies (IgM > IgG) that bind to hamster leukocytes and endothelial cells. Transplantation of either the heart or liver from hamster rat results in release of hamster hematolymphoid cells from the graft, which lodge in the recipient spleen (cell migration), where recipient T- and B-cell populations initiate DNA synthesis within one day. There is marked stimulation of splenic IgM++(bright)/IgD+(dull) B cells in the marginal zone and red pulp, which account for 48% of the total splenic blast cell population by 4 days after liver transplantation. CD4+ predominant T-cell proliferation in the splenic periarterial lymphatic sheath and paracortex of peripheral lymph nodes occurs almost simultaneously. The effector phase of rejection in cardiac recipients is dominated by complement-fixing IgM antibodies, which increase daily and result in graft destruction in 3 to 4 days, even in animals treated with FK506. In liver recipients, combined antibody and cellular rejection, associated with graft infiltration by OX8+ natural killer, and fewer W3/25+ (CD4) lymphocytes, are responsible for graft failure in untreated recipients at 6 to 7 days. FK506 inhibits the T-cell response in liver recipients and significantly prolongs graft survival, but does not prevent the rise or deposition of IgM antibodies in the graft. However, a single injection of cyclophosphamide 10 days before transplantation effectively depletes the splenic IgM++(bright)/Ig+(dull) cells and in combination with FK506, results in 100% survival of both cardiac and hepatic xenografts for more than 60 days. Although extrapolation of morphological findings to functional significance is fraught with potential problems, we propose the following mechanisms of xenografts rejection. The reaction initially appears to involve primitive host defense mechanisms, including an IgM-producing subpopulation of splenic B cells and natural killer cells. Based on the reaction and distribution of OX8+ and W3/25+ cells, antibody-dependent cell cytotoxicity and delayed-type hypersensitivity responses seem worthy of further investigation as possible effector mechanisms. Effective control of xenograft rejection is likely to require a dual pharmaceutical approach, one to contain T-cell immunity and another to blunt the primitive B-cell response.

[The laryngeal mask with > 1900 general anesthesias--report of experiences]

Since November 1990 until January 1993, the laryngeal mask airway was employed for 1925 general anaesthesias, i.e. 19.6% of all general anaesthesias in our hospital. On the basis of the protocols the age distribution of the patients, the practice of anaesthesia (premedication with oral benzodiazepines, induction with thiopental, anaesthesia sustained with enflurane/nitrous oxide/oxygen) and the complications are reported. The complications not directly related to the laryngeal mask were: hypotension (5.92%), dysrhythmias (3.17%) and hypertensive states (1.71%). Other complications directly related to the laryngeal mask (bronchospasm, laryngospasm, difficult insertion of the mask, intraoperative vomiting) were less than 1.3% each. One aspiration was recorded, but could not be attributed to the laryngeal mask. Complications with major influence on the postoperative course and hospital stay were not seen.

Seroprevalence of HIV-1 and HIV-2 infection among children diagnosed with protein-calorie malnutrition in Nigeria

Excessive weight loss due to protein calorie malnutrition (PCM) is a significant problem in Nigerian children. This syndrome may be difficult to differentiate from the wasting disease caused by human immunodeficiency virus type 1 (HIV-1) infection. We studied 70 children admitted to the Baptist Medical Center in Ogbomosho, Nigeria in 1990 with PCM for prevalence of antibodies to HIV-1 and HIV-2. The cohort was from low-risk mothers and had a median age of 25 months (range, 4 months-9 years) with a weight deficit of at least 20% of the theoretical weight for age. Two sera were positive for anti-HIV-1 by both ELISA and Western blot (WB). A high prevalence of samples negative for HIV-1 antibody by ELISA were repeatedly reactive (11%, 8/70) or indeterminate (46%, 32/70) by WB. None of the sera was positive for antibody to HIV-2. There was no correlation of ELISA positivity or extent of WB banding with successful recovery from malnutrition. These results indicate a relatively low but significant prevalence of HIV-1 infection in Nigerian children with PCM. The high prevalence of indeterminate reactions in WB assays for HIV-1 suggests that other procedures may be necessary for confirmatory diagnosis of HIV-1 infection in this African population.

The Latin American trial of psychosocial support during pregnancy: a social intervention evaluated through an experimental design

Perinatal health problems are a public health priority in Latin America. Among the identified risk factors, psychological and social conditions play a crucial role. However, care during pregnancy and delivery in the region is usually hospital-centered and does not address women's psychological and social conditions. The preeminence of research on perinatal health, along with the necessity for testing interventions that represent alternative models to improve women's health, gave the Latin American Network for Perinatal and Reproductive Research grounds to develop a multicenter randomized controlled trial to evaluate a program of social support and health education during pregnancy. The conceptual framework for this study was based on an ecological model of social support, i.e. a model in which social support and health education play a synergistic role and are meant to modify stressful situations and negative health-related behaviors. The target population consisted of women attending obstetric hospitals before the 22nd gestational week, at high psychological and social risk (n = 2236). The intervention consisted of four to six home visits, carried out by social workers, and had four main components: the reinforcement of pregnant women's social support network, emotional support, health education, and the improvement of health services utilization. The main foci of the intervention were determined after an ethnographic study was carried out to identify stress-producing situations and needs for support during pregnancy. Besides the home visits, the program also offered a hot-line, an office in the hospital, a specially designed poster and booklet, and a 'guided tour' of the health institution. Since this was a multicenter trial, the program's standardization was a crucial methodological aspect that was achieved through the training course for the home-visitors team. Biological and psychosocial outcomes were measured in both experimental and control groups at the 36th week of gestational age, post-partum and at the 40th day after delivery. The attributes of the multicenter population showed an important variability, reflecting differences in the countries or hospitals' population prevalent attributes. The results of the program's implementation were analyzed, demonstrating that home visitors adapted topics discussed during the interviews to the women's conditions and the stage of pregnancy during which the visit took place.(ABSTRACT TRUNCATED AT 400 WORDS)

Pathophysiology and prognostic significance of Holter-detected ST segment depression after myocardial infarction. The Tissue Plasminogen Activator: Toronto (TPAT) Study Group

OBJECTIVES

We performed Holter monitoring on days 4 and 7 after acute myocardial infarction in 109 patients to assess whether ST segment shift would identify those with more severe coronary artery disease, left ventricular dysfunction and unfavorable prognosis.

BACKGROUND

Silent myocardial ischemia is a frequent and prognostically significant event after acute myocardial infarction. However, the specific pathophysiologic mechanisms and the impact of thrombolytic therapy are uncertain.

METHODS

In addition to Holter monitoring, patients underwent exercise testing, radionuclide angiography on days 1 and 9 and quantitative coronary angiography on day 9.

RESULTS

Thirty-five patients (32%) had ST segment depression and had similar recombinant tissue-type plasminogen activator (rt-PA) treatment assignment and a reduced cross-sectional area of the infarct-related artery (0.59 +/- 0.57 vs. 1.04 +/- 1.26 mm2, p < 0.05). Global left ventricular function improved from day 1 to day 9 in patients without (4% +/- 11%, p < 0.001) but not in those with (0% +/- 7%) ST segment depression. In-hospital event rates were similar; however, follow-up 18 +/- 11 months after hospital discharge revealed a greater frequency of death and recurrent myocardial infarction in patients with compared with those without ST segment depression (27% vs. 6%, p = 0.03).

CONCLUSIONS

After acute myocardial infarction, approximately one third of patients have ST segment depression on Holter monitoring, independent of the use of thrombolytic therapy. The unfavorable prognosis observed in these patients may be related to greater lumen obstruction in the infarct-related artery and lack of improvement in left ventricular function.

Aggressive clinical pattern of angina at restenosis following coronary angioplasty in unstable angina

The frequency, clinical pattern, and timing of recurrent angina following successful single-lesion percutaneous transluminal coronary angioplasty (PTCA) was assessed in a consecutive group of 104 patients with stable angina and in 85 with unstable angina. In addition, the relationship between lesion morphology and angiographic features and the pattern of recurrent angina was determined. Restenosis, defined as recurrence of symptoms with > 50% stenosis at the site of PTCA, occurred in 25 (24%) of the stable group and in 23 (27%) of the unstable group (p = NS). The pattern of angina at repeat presentation was aggressive in nature in 8% of the stable group and in 48% of the unstable group (p = 0.002). The time interval between the recurrence of symptoms and repeat coronary angiogram or PTCA was longer in the nonaggressive group than in the aggressive group, 16 +/- 12.1 and 5 +/- 6.8 weeks, respectively (p < 0.003). The key factors predicting the recurrent angina pattern identified by multiple logistic regression analysis were the angina status pre-PTCA (p = 0.001) and the presence of double-vessel disease (p = 0.01). An aggressive pattern of angina at the time of restenosis is frequent in patients with unstable angina at the time of PTCA, and close post-PTCA surveillance is necessary in these patients.

A randomized trial of psychosocial support during high-risk pregnancies. The Latin American Network for Perinatal and Reproductive Research

BACKGROUND

It is often suggested that psychological and social support and health education for women at high risk for delivering a low-birth-weight infant can improve the outcomes of pregnancy, but the evidence is inconclusive. We undertook this prospective trial to evaluate a program of home visits designed to provide psychosocial support during pregnancy.

METHODS

At four centers in Latin America, 2235 women at higher-than-average risk for delivering a low-birth-weight infant were recruited before the 20th week of pregnancy. The women were randomly assigned either to an intervention group (n = 1115) that received four to six home visits from a nurse or social worker in addition to routine prenatal care or to a control group (n = 1120) that received only routine prenatal care (with a mean of eight prenatal visits). The principal measures of outcome were low birth weight (< 2500 g), preterm delivery (< 37 weeks of gestation), and specified categories of maternal and neonatal morbidity.

RESULTS

The women who received the home visits as well as routine prenatal care had outcomes that differed little from those of the women who received only routine care. The risks of low birth weight (odds ratio for the intervention group as compared with the control group, 0.93; 95 percent confidence interval, 0.68 to 1.28), preterm delivery (odds ratio, 0.88; 95 percent confidence interval, 0.67 to 1.16), and intrauterine growth retardation (odds ratio, 1.08; 95 percent confidence interval, 0.83 to 1.40) were similar in the two groups. There was no evidence that the intervention had any significant effect on the type of delivery, the length of hospital stay, perinatal mortality, or neonatal morbidity in the first 40 days. There was no protective effect of the psychosocial-support program even among the mothers at highest risk.

CONCLUSIONS

Interventions designed to provide psychosocial support and health education during high-risk pregnancies are unlikely to improve maternal health or to reduce the incidence of low birth weight among infants.