[Handbook for the preparation of evidence-based documents. Tools derived from scientific knowledge]. / Manual para la elaboración de documentos basados en la evidencia. Herramientas derivadas del conocimiento científico.

OBJECTIVES: This handbook is intended to be an accessible, easy-to-consult guide to help professionals produce or adapt Evidence-Based Documents. Such documents will help standardize both clinical practice and decision-making, the quality always being monitored in such a way that established references are complied with. MATERIALS AND METHODS: Evidence-Based Health Care Committee, a member of "Virgen del Rocío" University Hospital quality structure, proposed the preparation of a handbook to produce Evidence-Based Documents including: a description of products, characteristics, qualities, uses, methodology of production, and application scope of every one of them. RESULTS: The handbook consists of seven Evidence-Based tools, one chapter on critical analysis methodology of scientific literature, one chapter with internet resources, and some appendices with different assessment tools. CONCLUSIONS: This Handbook provides general practitioners with a great opportunity to improve quality and as a guideline to standardize clinical healthcare, and managers with a strategy to promote and encourage the development of documents in an effort to reduce clinical practice variability, as well as giving patients the opportunity of taking part in planning their own care.

Cardiac allograft vasculopathy: coronary computed tomography and virtual histology assessment.

INTRODUCTION: Cardiac allograft vasculopathy remains the leading cause of late morbidity and mortality in heart transplantation. The main diagnostic methods, coronary angiography or intracoronary ultrasound (when angiography is normal), are invasive. Other study methods, such as coronary computed tomography (CT) and virtual histological analysis, have not been widely assessed in this condition. OBJECTIVE: The objective of this study was to assess the correlation between data obtained from analysis of virtual histology compared with those obtained from the performance of coronary CT in cardiac transplant recipients. MATERIALS AND METHODS: During the same admission we performed coronary angiography and intravascular ultrasound with virtual histological analysis (automatic pull-back in anterior descending artery and one additional vessel if the former was normal) as well as coronary CT. RESULTS: The study included 10 patients. Virtual histology was done in segments with intimal thickening>0.5 mm, defining 2 groups of plaque, those with an inflammatory component (necrotic core>30% and calcium) versus those without it defined as the combination of both being <30%. A calcium component of the inflammatory plaque allowed coronary CT detection. CONCLUSIONS: The detection of inflammatory plaque in graft vessel disease can be based on an initial noninvasive method, such as coronary CT, although confirmation requires further study.

Safety and effectiveness of ivabradine after cardiac transplantation.

BACKGROUND: Heart denervation is the primary cause of sinus tachycardia in transplant recipients. Drugs are usually needed to treat associated symptoms. OBJECTIVE: To evaluate the safety and effectiveness of the novel I(f) channel antagonist ivabradine to control heart rate after transplantation. METHODS: Of 316 heart transplant recipients at a single center since 1991, ivabradine was administered in 15 patients, in addition to ß-blockers in 4 patients and contraindication to use of ß-blocker therapy in the others. A prospective follow-up study was conducted to identify possible adverse effects, tolerance, and drug effects on heart rate and control of symptoms. RESULTS: Of the 15 patients, 13 were men; overall mean (SD) patient age was 46 (4.6) years. In all patients, treatment was begun after verification of basal heart rate greater than 100 bpm and after other causes of sinus tachycardia had been ruled out. During follow-up of 1.13 (0.3) years, no substantial adverse effects were observed. It was possible to reach the maximum drug dosage in all patients, achieving a reduction in basal heart rate of 33 (6.2) bpm. All patients reported substantial clinical improvement, and demonstrated an increase in functional class. CONCLUSION: Ivabradine is safe, well tolerated, and effective in heart transplant recipients.

Usefulness of cardio MRI on thrombosis of coronary aneurysm as an infrequent cause of ST-elevation coronary syndrome.

We present an unusual case of thrombosis of coronary aneurysm causing myocardial infarction with ST-elevation in precordial leads. Emergent coronary angiography showed thrombotic occlusion of an aneurysm in the proximal segment of the left anterior descendent coronary artery (LAD). After the administration of tenecteplase, pain and ST-elevation disappeared with no overt complications. Cardiac magnetic resonance imaging (MRI) performed two weeks after admission showed thrombi partially filling the aneurysm together with further information regarding coronary anatomy, as well as a preserved global function even though delayed enhancement of the myocardium was patent throughout the territory irrigated by LAD. This case supports cardio MR usefulness in Kawasaki disease in order not only to depict coronary abnormalities, but also to provide accurate information regarding function and viability in a non-invasive way. It also highlighted the relevance of a proper selection of the sequence technique when thrombus is suspected. All these advantages point out to cardiac MRI as the modality of choice in the follow-up of patients in this clinical scenario.

[Circumscribed choroidal hemangioma treated with photodynamic therapy]. / Hemangioma circunscrito de coroides tratado con terapia fotodinámica.

CLINICAL CASE: A 45-year-old male referred with a scotoma in the left eye of 2 months' evolution. A peripapillary tumor was found, with a basal diameter of 7 mm and thickness 3.4 mm. It was diagnosed as a circumscribed choroidal hemangioma. It was decided to treat the patient using photodynamic therapy. After 4 sessions and 17 months follow-up, the patient remained asymptomatic and visual acuity was stable. There was evidence of subretinal fibrosis and no subretinal fluid was found. DISCUSSION: Photodynamic therapy is a good option for the treatment of circumscribed choroidal hemangioma given the minimal damage is causes to the adjacent retina.

Clinical randomized controlled trial of chemomechanical caries removal (Carisolv).

OBJECTIVES: The purpose of this study was to compare the chemomechanical caries-removal system (Carisolv) with high-speed excavation in cavitated occlusal caries of primary molars. Design and setting. The study was a randomized controlled, clinical trial in which the two techniques were compared in each subject. Participants were chosen from public schools, in Maracaibo County, Zulia State, Venezuela. SAMPLE AND METHODS: The sample consisted of 80 primary molars selected from 40 children (mean age 7.7+/-0.7 years). Each patient had at least two contralateral primary molars with cavitated occlusal caries and approximately equal-size access to lesions. The outcome variables were: clinically complete caries removal, size of the opening of the cavity, volume of carious tissue removed, pain during caries removal, anaesthesia requested by the patient, caries-removal time, and behaviour and preference of patients. RESULTS: All treated molars were clinically caries free whichever caries-removal procedure was used. When Carisolv' was used the final cavity entrance sizes were smaller (P<0.001) and the estimated volume of tissue removed was less (P<0.001). The time taken for caries removal was three times longer (7.51+/-1.83 min, P<0.001). Some pain was reported by seven (17.5%) participants when Carisolv was used, compared with 16 (40%) when high-speed excavation was used (P<0.05). Using the Carisolv method there was a higher proportion of patients with positive behaviour (P<0.01), and 71.0% (P<0.05) preferred this treatment. CONCLUSION: Carisolv is an effective clinical alternative treatment for the removal of occlusal dentinal caries in cavitated primary molars; it is more conservative of dental tissue and appeared to be more comfortable for most patients, although the clinical time spent is longer than when using high-speed excavation.

Population pharmacokinetics of digoxin in pediatric patients.

Digoxin pharmacokinetics were studied in a pediatric population with an age range of 6 days to 1 year using the population pharmacokinetic approach. Digoxin data were analyzed by mixed-effects modeling according to a one-compartment steady-state pharmacokinetic model using NONMEM software. The final model selected for the population prediction of digoxin clearance in pediatric patients was as follows: [equation: see text] Individual empirical Bayesian estimates were generated on the basis of the population estimates and were used to correlate the optimum dose of digoxin and patient age according to the following equation: [equation: see text] This equation and its derived nomogram may be used for the initial dosing of digoxin in children aged between 0 and 1 year. The use of this nomogram in routine monitoring requires further pharmacokinetic and clinical validation.

[Contribution of color Doppler in the diagnosis of bilateral ductus arteriosus]. / Contribución del Doppler color al diagnóstico de ductus arterioso bilateral.

We report a neonate with distal bilateral ductus arteriosus origin of nonconfluent pulmonary arteries which was only diagnosed accurately by 2-D echo Doppler color flow mapping in the context of situs ambiguous, univentricular A-V connection and pulmonary atresia with normal systemic/pulmonary venous drainage. The color flow appearance of this singular vascular anatomy was enhanced after prostaglandin administration, which, allowed us to see an image resembling a "moustache morphology". At 36 months of age, and after a successful bilateral 4 mm modified Blalock Taussig shunt implantation by sequential approach, the patient is waiting for the next surgical step which will include a restoration of the confluence of the pulmonary arteries with bidirectional Glenn operation. Brief embryological and differential diagnosis comments are discussed.

[Clinical and echocardiographic impact of neonatal aortic valvuloplasty]. / Impacto clínico y ecocardiográfico de la valvuloplastia aórtica neonatal.

OBJECTIVES: The selection of patients for balloon aortic valvuloplasty is a vital clinical challenge in neonatal aortic stenosis. The present study was designed to establish possible predicting factors for poor results after balloon therapy. PATIENTS AND METHODS: 2D echocardiographic, Doppler color and clinical variables (grade of cardiac failure, aortic "anulus", mitral anulus, left ventricular diameter, ascending aorta, instantaneous Doppler gradient, and grade of aortic regurgitation) were analyzed in 32 neonates submitted to balloon dilation at 22 +/- 18 days of life. The evaluations were conducted during three periods in respect to balloon therapy (A: before; B: immediately after, and C: mid-term follow-up). The outcome in both, B and C periods was defined as favorable (all survivors with Doppler gradient < or = 70 mmHg and no other intervention on the valve) and unfavorable (death, first stage of univentricularization, valvular replacement or survivors with Doppler gradient > 70 mmHg). Mean values between subgroups were compared by Wilcoxon test; unconditional logistic regression was used to analyze the impact of cardiac failure and anatomic variables (continuous, categorized or Z) on the outcome. RESULTS: The Doppler gradient decreased from 70 +/- 28 to 34 +/- 14 mmHg after the valvuloplasty, and no changes were detected in the follow-up period (36 +/- 8 mmHg). An immediate favorable result was obtained in 72% of the patients; its consisted of 50% in period C. Nine neonates had an immediate unfavorable outcome (6 deaths and 3 with Norwood operation). In the follow-up, three patients had valvular replacement, one patient Doppler gradient > 70 mmHg and one patient with left ventricular endomyocardial abnormalities died. The severe cardiac failure (odds ratio: 33; CL 2.4-443; p = 0.008) and all categorized anatomic variables (aortic "anulus" < or = 6 mm; mitral anulus < or = 9 mm; ascending aorta < or = 8 mm; left ventricular diameter < or = 13 mm) were related with the immediate poor outcome. At 7.6 years, survival and freedom with no valvular replacement nor reintervention probability rates were 83% and 67%, respectively. CONCLUSIONS: 2D echo Doppler provides essential information about the anatomic and functional lesions coexisting with severe or critical aortic stenosis in neonates. Patients with left heart hypoplasia and severe heart failure should not be candidates for balloon valvuloplasty. The degree of residual aortic regurgitation and endomyocardial abnormalities of the left ventricle play an important role in the mid-term follow-up.

[Prevalence of HTLV-I antibodies and possible risk factors in Chilean prostitutes]. / Prevalencia de anticuerpos anti HTLV-I y posibles factores de riesgo en prostitutas chilenas.

Aiming to know the prevalence of HTLV-1 infection among high risk groups in Santiago, the antibodies against HTLV-1 were measured in 502 prostitutes coming from north and east Santiago. Antibodies were measured using ELISA and the positive samples were confirmed with an indirect immunofluorescence technique. Four subjects were positive, establishing a HTLV-1 infection prevalence of 0.8%. This number similar to that of other groups of prostitutes from South America and lower than that of prostitutes from Central America, region in which this infection is endemic. The measured prevalence was similar to that of other non promiscuous groups, suggesting that sexual transmission does not play an important role in our population.

[Echocardiographic study of hypertrophic myocardiopathy in children. Distribution and changing morphological course]. / Estudio ecocardiográfico de la miocardiopatía hipertrófica en niños. Distribución y evolución morfológica cambiante.

Thirty-eight children with diagnosis of hypertrophic cardiomyopathy were analyzed by M-Mode, two-dimensional and Doppler. The patients ranged in age from 7 days and 20 years (average 5 years). Three groups appear, based in morphologic myocardial affection. Patients with biventricular involvement ranged in age from 20 days and 6 months (group 1), patients aged until 6 years with left ventricular concentric morphology by echocardiographic examination (group 2), and the older in age group (group 3) with localized mid-ventricular hypertrophy in the same ventricle. A certain degree of obstruction was detected in 15 cases (46.8%). In both this aspect and systolic anterior motion of mitral valve and mitral regurgitation, the highest frequency was obtained in group 3. With respect to others echocardiographic parameters, like isovolumetric relaxation time and left ventricle short fraction, no variations have been observed between the three groups. Very interesting is the fact that one third of the patients of group 1 improved markedly, and another third of cases died. In conclusion, the echocardiography permits identify three groups in the hypertrophic cardiomyopathy in children, according to age and anatomic region affected. The variability of evolution in the youngest group of patients, suggest that certain cases are not true myocardiopathies, but myocardial hypertrophies secondaries to other problems. Only the oldest group supply the classics parameters of the adult hypertrophic cardiomyopathy.

Infectious endocarditis in children.

With the object of analyzing current characteristics of infectious endocarditis (IE) in children, we carried out a retrospective study of 23 cases of IE in children under 15 years of age seen at the Hospital Ramón y Cajal in Madrid (Spain) between 1977 and 1985. The incidence was high (1.3 cases per 1000 children admitted). The male/female ratio was 2:1. Eight patients were under 2 years of age and 15 over 2 years, the majority being adolescents. The two groups presented marked etiological and prognostic differences. Congenital heart disease was the predisposing factor in 20 of the 23 cases. Streptococcus viridans (nine cases) and Staphylococcus aureus (eight cases) were the most frequent organisms. Fourteen cases were on a native valve and nine were secondary (seven of these on prosthetic patches). In spite of advances in therapy, IE continues to be a severe illness: the mortality rate in our series was 26%. Factors associated with a poor prognosis were: age less than 2 years, Staphylococcus aureus as the causative agent, and the presence of prosthetic material.

[Isolated ventricular inversion associated with complete atrioventricular septal defect with total anomalous pulmonary venous drainage]. / Inversión ventricular aislada asociada a defecto completo del septo atrioventricular con drenaje venoso pulmonar anómalo total.

Based upon the description of the clinico-pathological characteristic of a case with isolated ventricular inversion plus other cardiac malformations, the clinical, diagnostic and embryo-pathological implications of this entity are reviewed.

[Atrioventricular septal defect with associated tetralogy of Fallot. Clinico-morphological aspects and surgical considerations]. / Defecto del septo atrioventricular con tetralogía de Fallot asociada. Aspectos clinicomorfológicos y consideraciones quirúrgicas.

In this work the clinical features, diagnostic methods, surgical procedures and postoperative follow-up are reviewed in 19 cases of atrioventricular septal defect with associated tetralogy of Fallot. The clinical situation was always related to the degree of pulmonary ischemia, that pointed out the urgency and need for a palliative surgical procedure before corrective surgery. There was no data in the ECG for the differential diagnosis of isolated forms of atrioventricular septal defect. In 50% of the cases the cardio-thoracic index was increased by right atrial enlargement. The diagnosis of the malformation was made in every case by means of 2D echocardiography. In 16 cases palliative surgery was done (aortic-pulmonary shunts), with one death (6.2%) due to facts unrelated to the technique. Of the 6 cases with corrective surgery (5 cases with previous shunts), one needed a mitral valve replacement (St Jude prosthesis). There was no mortality in this group and the functional status in the long-term follow-up was: 3 cases were in the functional class I and 3 cases in class II. The overall mortality for all surgical procedures carried out was 4.3%. In conclusion, we consider the use of the corrective surgery adequate to the clinical stability of the patients with atrioventricular septal defect with associated Fallot's tetralogy.

[Markers of HIV infection in prostitutes: analysis of preventive and risk factors]. / Marcadores de infeccion por VIH en prostitutas: analisis de factores preventivos y de riesgo.

We studied 501 prostitutes from the northern and eastern areas of Santiago in november and december, 1987. HIV infection was studied by the HIV antibody and also by HIV antigen. At that time no positive reactors were found. Prostitutes from the northern area were older, of a lower socioeconomic background and less promiscuous, in comparison to prostitutes of the eastern area. However, other disorders of sexual transmission were found in 41% of prostitutes of the northern area and in only 28% of those from the eastern area. This difference may be attributed to the more frequent use of preservative in the latter group.