Demographic and clinical characteristics of pulmonary arterial hypertension caused by schistosomiasis are indistinguishable from other etiologies

Abstract INTRODUCTION: Pulmonary arterial hypertension (PAH) is a serious pulmonary circulation disease caused by several etiologies, including schistosomiasis. The present study retrospectively evaluated the clinical and hemodynamic characteristics of patients with schistosomal PAH (PAH-Sch) compared to those of non-Sch PAH patients (non-Sch PAH). METHODS: Patients treated at the Pronto-Socorro Cardiológico de Pernambuco and diagnosed by right cardiac catheterization were divided into PAH-Sch and non-Sch PAH groups. Their socio-demographic and clinical characteristics, N-terminal-pro B-type natriuretic peptide (NT-proBNP), and echocardiography and hemodynamic parameters were retrospectively reviewed. RESULTS: Among the included 98 patients (mean age, 45 ± 14 years; 68 women [69.4%]), we found 56 PAH-Sch and 42 non-Sch PAH. The age distribution was heterogeneous in the PAH-Sch group, with patients predominantly ranging from 50-59 (p <0.004). Dyspnea was the most common symptom, reported by 92 patients (93.8%), and commonly present for over two years prior to diagnosis. Clinical symptoms were similar in both groups, with no differences in functional class, pulmonary artery systolic pressure (p = 0.102), 6-minute walk test score (p = 0.234), NT-proBNP serum levels (p = 0.081), or hemodynamic parameters. CONCLUSIONS: Patients with PAH-Sch present clinical, laboratory, and hemodynamic profiles similar to those with PAH resulting from other etiologies of poor prognosis. PAH is an important manifestation of schistosomiasis in endemic regions that is often diagnosed late.

Fator natriurético atrial: ele é o responsável pela hiponatremia e natriurese em neurocirurgia? / Atrial natriuretic factor: is it responsible for hyponatremia and natriuresis in neurosurgery?

RESUMO Objetivo: Avaliar a presença de hiponatremia e natriurese, bem como suas associações com o fator natriurético atrial em pacientes de neurocirurgia. Métodos: Foram incluídos 30 pacientes submetidos à ressecção de tumor intracraniano e à clipagem de aneurisma cerebral. Os níveis plasmáticos e urinários de fator natriurético atrial foram medidos durante os períodos pré e pós-operatório. Resultados: Hiponatremia esteve presente em 63,33% dos pacientes, particularmente no primeiro dia pós-operatório. Observou-se natriurese em 93,33% dos pacientes, principalmente no segundo dia pós-operatório. Os níveis plasmáticos de fator natriurético atrial estavam aumentados em 92,60% dos pacientes em pelo menos um dos dias pós-operatórios, mas não houve associação estatisticamente significante entre fator natriurético atrial e sódio plasmático, e entre fator natriurético atrial e sódio urinário. Conclusão: Após neurocirurgia, na maior parte dos pacientes, estiveram presentes hiponatremia e natriurese; contudo, o fator natriurético atrial não pôde ser considerado diretamente responsável por tais alterações nos pacientes neurocirúrgicos. Provavelmente, há o envolvimento de outros fatores natriuréticos.

ABSTRACT Objective: To evaluate the presence of hyponatremia and natriuresis and their association with atrial natriuretic factor in neurosurgery patients. Methods: The study included 30 patients who had been submitted to intracranial tumor resection and cerebral aneurism clipping. Both plasma and urinary sodium and plasma atrial natriuretic factor were measured during the preoperative and postoperative time periods. Results: Hyponatremia was present in 63.33% of the patients, particularly on the first postoperative day. Natriuresis was present in 93.33% of the patients, particularly on the second postoperative day. Plasma atrial natriuretic factor was increased in 92.60% of the patients in at least one of the postoperative days; however, there was no statistically significant association between the atrial natriuretic factor and plasma sodium and between the atrial natriuretic factor and urinary sodium. Conclusion: Hyponatremia and natriuresis were present in most patients after neurosurgery; however, the atrial natriuretic factor cannot be considered to be directly responsible for these alterations in neurosurgery patients. Other natriuretic factors are likely to be involved.

Scale and scope economies in Mexican private medical units / Economías de escala y alcance en unidades médicas privadas en México

Objective. To evaluate technical efficiency and potential presence of scale and scope economies in Mexican private medical units (PMU) that will improve management decisions. Materials and methods. We used data envelopment analysis methods with inputs and outputs for 2 105 Mexican PMU published in 2010 by the Instituto Nacional de Estadística y Geografía from the "Estadística de Unidades Médicas Privadas con Servicio de Hospitalización (PEC-6-20-A)" questionnaire. Results. The application of the models used in the paper found that there is a marginal presence of economies of scale and scope in Mexican PMU. Conclusions. PMU in Mexico must focus to deliver their services on a diversified structure to achieve technical efficiency.

Objetivo. Evaluar la eficiencia técnica y la presencia de potenciales economías de escala y alcance en unidades médicas privadas (UMP) mexicanas, de forma que sea posible establecer planes para la mejora de su gestión. Material y métodos. Se utilizó el método de Análisis Envolvente de Datos con información de insumos y productos para 2 105 UMP del año 2010 publicada por el Instituto Nacional de Estadística y Geografía a través del cuestionario denominado "Estadística de Unidades Médicas Privadas con Servicio de Hospitalización (PEC-6-20-A)". Resultados. La aplicación de los modelos encuentra una presencia marginal de economías de escala y alcance en las UMP mexicanas. Conclusiones. La operación de las UMP en México debe enfocarse a prestar servicios bajo un modelo diversificado para alcanzar mejores niveles de eficiencia técnica.

The role of oxytocin in cardiovascular regulation

Studies of body volume expansion have indicated that lesions of the anteroventral third ventricle and median eminence block the release of atrial natriuretic peptide (ANP) into the circulation. Detailed analysis of the lesions showed that activation of oxytocin (OT)-ergic neurons is responsible for ANP release, and it has become clear that activation of neuronal circuitry elicits OT secretion into the circulation, activating atrial OT receptors and ANP release from the heart. Subsequently, we have uncovered the entire functional OT system in the rat and the human heart. An abundance of OT has been observed in the early development of the fetal heart, and the capacity of OT to generate cardiomyocytes (CMs) has been demonstrated in various types of stem cells. OT treatment of mesenchymal stem cells stimulates paracrine factors beneficial for cardioprotection. Cardiovascular actions of OT include: i) lowering blood pressure, ii) negative inotropic and chronotropic effects, iii) parasympathetic neuromodulation, iv) vasodilatation, v) anti-inflammatory activity, vi) antioxidant activity, and vii) metabolic effects. OT actions are mediated by nitric oxide and ANP. The beneficial actions of OT may include the increase in glucose uptake by CMs and stem cells, reduction in CM hypertrophy, oxidative stress, and mitochondrial protection of several cell types. In experimentally induced myocardial infarction in rats, continuous in vivo OT delivery improves cardiac healing and cardiac work, reduces inflammation, and stimulates angiogenesis. Because OT plays anti-inflammatory and cardioprotective roles and improves vascular and metabolic functions, it demonstrates potential for therapeutic use in various pathologic conditions.

Assessment of the left atrial volume index and plasma NT-proANP level in patients with acute ST-elevation myocardial infarction

OBJECTIVES: Acute ST-elevation myocardial infarction is associated with ventricular dysfunction due to ischemia-induced progressive myocardial damage. The decrease in ventricular compliance causes left atrial dilatation and stretching of the atrial myocardium, which are the main stimuli for the secretion of atrial natriuretic peptide. The aim of this study was to evaluate left atrial dimensions and atrial natriuretic peptide levels in patients early after their first acute ST-elevation myocardial infarction and assess the probable interaction between coronary lesions and these measurements. METHODS: A total of 110 patients with acute myocardial infarction and 50 controls were studied. Plasma atrial natriuretic peptide was measured at admission. Left ventricular function, diameter, and volume index were evaluated using transthoracic echocardiography. Gensini and vessel scores of the patients who underwent coronary angiography were calculated. RESULTS: Plasma atrial natriuretic peptide in the patients with myocardial infarction was increased compared with that in controls (3.90±3.75 vs. 1.35±0.72 nmol/L, p<0.001). Although the left atrial diameter was comparable in patients and controls, the left atrial volume index was increased in patients with acute myocardial infarction (26.5±7.1 vs. 21.3±4.9 mL/m2, p<0.01). Multivariate regression analysis showed a strong independent correlation between the left atrial volume index and the plasma atrial natriuretic peptide level (β = 0.23, p = 0.03). CONCLUSIONS: The left atrial volume index and plasma atrial natriuretic peptide level were correlated in patients with acute myocardial infarction. .

Avaliação do ventrículo direito pelo ecocardiograma com doppler tecidual na embolia pulmonar aguda / Right ventricular assessment by tissue-Doppler echocardiography in acute pulmonary embolism

FUNDAMENTO: A avaliação da função Ventricular Direita (VD) pelo ecocardiograma em pacientes com Tromboembolismo Pulmonar (TEP) é complexa, frequentemente qualitativa; o Doppler tecidual tem sido utilizado para avaliação semiquantitativa dessa câmara, com algumas limitações. OBJETIVO: Avaliar a função do VD no TEP pelo ecocardiograma com Doppler tecidual, complementando com o peptídeo atrial natriurético (BNP). MÉTODOS: Foram estudados pacientes com TEP pelo ecocardiograma com Doppler tecidual e BNP até 24 horas do diagnóstico, obtendo-se as velocidades miocárdicas (s'), strain, strain rate e índice de performance miocárdica do VD; disfunção do VD foi iagnosticada por hipocinesia da câmara, movimento anormal septal e relação VD/VE >1. De acordo com o BNP os pacientes foram divididos em Grupo I, BNP < 50 pg/mL e Grupo II, BNP > 50 pg/mL. RESULTADOS: De 118 pacientes, 100 (60 homens, idade = 55 ± 17 anos) foram analisados; observou-se disfunção do VD em 28%, mais frequentemente no grupo II (19 vs. 9 pacientes, p < 0,001). O grupo II era mais idoso (64 ± 19 vs. 50 ± 15 anos), apresentava menor velocidade de s' (10,5 ± 3,5 vs. 13,2 ± 3,1 cm/s) e maior pressão pulmonar (48 ± 11 vs. 35 ± 11 mmHg), p < 0,001 para todos. O ponto de corte de s' para disfunção do VD foi de 10,8 cm/s (especificidade = 85%, sensibilidade = 54%), com moderada correlação entre o BNP e a onda s'(r = -0,39). CONCLUSÃO: No TEP, a disfunção do VD pelo ecocardiograma se acompanha de elevação do BNP; apesar confirmar adequadamente a presença de disfunção do VD, o Doppler tecidual apresenta sensibilidade limitada para este diagnóstico.

BACKGROUND: Assessment of the right ventricular (RV) function by echocardiography in patients with pulmonary thromboembolism (PTE) is complex and frequently qualitative. Tissue Doppler has been used for the semiquantitative assessment of this chamber, although with some limitations. OBJECTIVE: To evaluate RV function in PTE using tissue-Doppler echocardiography, in addition to atrial natriuretic peptide (BNP). METHODS: Patients with PTE were studied using tissue-Doppler echocardiography and BNP up to 24 hours after diagnosis; myocardial velocities (s'), strain, strain rate and RV myocardial performance index were obtained. RV dysfunction was diagnosed by chamber hypokinesia, abnormal septal motion and a RV/LV ratio >1. According to their BNP levels, the patients were divided into Group I, BNP < 50 pg/mL and Group II, BNP > 50 pg/mL. RESULTS: Of 118 patients, 100 (60 men, age = 55 ± 17 years) were analyzed; RV dysfunction was observed in 28%, more frequently in group II (19 vs. 9 patients, p < 0.001). Patients in group II were older (64 ± 19 vs. 50 ± 15 years), and had lower s' velocity (10.5 ± 3.5 vs. 13.2 ± 3.1 cm/s), and higher pulmonary pressure (48 ± 11 vs. 35 ± 11 mmHg), p < 0.001. The cut-off point of s' for RV dysfunction was 10.8 cm/s (specificity = 85%, sensitivity = 54%), with moderate correlation between BNP and s' wave (r = -0.39). CONCLUSION: In PTE, RV dysfunction on echocardiography is accompanied by BNP elevation; although tissue-Doppler imaging adequately confirms the presence of RV dysfunction, it has a limited sensitivity for this diagnosis.

Comparação da acurácia de preditores de mortalidade na pneumonia associada à ventilação mecânica / Comparing the accuracy of predictors of mortality in ventilator-associated pneumonia

OBJETIVO: Níveis de procalcitonina, midregional pro-atrial natriuretic peptide (MR-proANP, pró-peptídeo natriurético atrial midregional),, C-terminal provasopressin (copeptina), proteína C reativa (CRP) e escore do Sequential Organ Failure Assessment (SOFA) são associados a gravidade e descritos como preditores de desfechos na pneumonia associada a ventilação mecânica (PAVM). Este estudo procurou comparar o valor preditivo de mortalidade desses biomarcadores na PAVM. MÉTODOS: Estudo observacional com 71 pacientes com PAVM. Níveis de procalcitonina, MR-proANP, copeptina e PCR, bem como escore de SOFA foram obtidos no dia do diagnóstico de PAVM, designado dia zero (D0), e no quarto dia de tratamento (D4) Os pacientes receberam tratamento antimicrobiano empírico, com modificações baseadas nos resultados de cultura. Os pacientes que morreram antes de D28 foram classificados como não sobreviventes. RESULTADOS: Dos 71 pacientes, 45 sobreviveram. Dos 45 sobreviventes, 35 (77,8 por cento) receberam tratamento antimicrobiano adequado, comparados com 18 (69,2 por cento) dos 26 não sobreviventes (p = 0,57). Os sobreviventes apresentaram valores significativamente mais baixos em todos os biomarcadores estudados, inclusive no escore de SOFA (exceto PCR) em D0 e D4. Em D0 e D4, a área sob a curva ROC foi maior para procalcitonina. Em D0, MR-proANP teve a maior razão de verossimilhança positiva (2,71) e valor preditivo positivo (0,60), mas a procalcitonina apresentou o maior valor preditivo negativo (0,87). Em D4, a procalcitonina apresentou a maior razão de verossimilhança positiva (3,46), o maior valor preditivo positivo (0,66) e o maior valor preditivo negativo (0,93). CONCLUSIONS: Os biomarcadores procalcitonina, MR-proANP e copeptina podem predizer mortalidade na PAVM, assim como o escore de SOFA. A procalcitonina tem o maior poder preditivo de mortalidade na PAVM.

OBJECTIVE: Levels of procalcitonin, midregional pro-atrial natriuretic peptide (MR-proANP), C-terminal provasopressin (copeptin), and C-reactive protein (CRP), as well as Sequential Organ Failure Assessment (SOFA) scores, are associated with severity and described as predictors of outcome in ventilator-associated pneumonia (VAP). This study sought to compare the predictive value of these biomarkers for mortality in VAP. METHODS: An observational study of 71 patients with VAP. Levels of procalcitonin, MR-proANP, copeptin, and CRP, together with SOFA scores, were determined at VAP onset, designated day 0 (D0), and on day 4 of treatment (D4). Patients received empirical antimicrobial therapy, with modifications based on culture results. Patients who died before D28 were classified as nonsurvivors. RESULTS: Of the 71 patients evaluated, 45 were classified as survivors. Of the 45 survivors, 35 (77.8 percent) received appropriate antimicrobial therapy, compared with 18 (69.2 percent) of the 26 nonsurvivors (p = 0.57). On D0 and D4, the levels of all biomarkers (except CRP), as well as SOFA scores, were lower in eventual survivors than in eventual nonsurvivors. For D0 and D4, the area under the ROC curve was largest for procalcitonin. On D0, MR-proANP had the highest positive likelihood ratio (2.71) and positive predictive value (0.60), but procalcitonin had the highest negative predictive value (0.87). On D4, procalcitonin had the highest positive likelihood ratio (3.46), the highest positive predictive value (0.66), and the highest negative predictive value (0.93). CONCLUSIONS: The biomarkers procalcitonin, MR-proANP, and copeptin can predict mortality in VAP, as can the SOFA score. Procalcitonin alone has the greatest predictive power for such mortality.

Biomarcadores en neumonías / Biomarkers in pneumonia

Las neumonías, tanto comunitarias como nosocomiales, constituyen una importante causa de morbimortalidad a nivel global y ocasionan además importantes costos sanitarios. Como en cualquier otro proceso infeccioso, una adecuada respuesta a la infección es un fenómeno complejo que requiere un apropiado y oportuno tratamiento antibiótico, así como una apropiada respuesta inflamatoria inicial para contener la proliferación y diseminación de los microorganismos, seguida por una respuesta antiinflamatoria compensatoria que restaure la homeostasis inicial. Recientes estudios han demostrado que una excesiva respuesta inflamatoria en sepsis y NAC severa puede asociarse con efectos deletéreos y peor pronóstico. Por otro lado, una exagerada respuesta antiinflamatoria puede tener efecto negativo en la resolución de la infección. Por lo tanto, una mejor comprensión de este delicado equilibrio proinflamatorio/antiinflamatorio y sus mediadores podrán ser de gran ayuda para valorar la presencia y gravedad de la neumonía así como su probable evolución. En estudios previos varios marcadores han sido ensayados: Proteína C reactiva (PCR), Procalcitonina (PCT), diversas interleuquinas (IL1, IL6, IL8 e IL10), factor de necrosis tumoral alfa (TNFalfa), etc., como marcadores de inflamación/infección, gravedad, fallo de tratamiento y pronóstico. La presente monografía tiene por objeto hacer una revisión sintética de la literatura reciente sobre el tema, tratando de explorar y objetivar fortalezas y debilidades de tales marcadores biológicos.

Community acquired and nosocomial pneumonia are considered a global health issue and a significant cause of morbility, mortality and important economic costs. As in other infectious diseases, an appropriate therapeutic response to the infection is a complex phenomenon that requires appropriate and timely antimicrobial treatment and acorrect initial inflammatory response to stop the microbial proliferation and dissemination, followed by an anti-inflammatory response to restore the initial homeostasis. Recently published studies have showed that exaggerated inflammatory response in sepsis and severe community acquired pneumonia may be associated with poorer outcomes. On the other hand, an exagerated inflammatory response may have a deleterious effect on the infection resolution. Consequently, a better understanding of the delicate balance inflammation/anti-inflammation and their mediators could be of great help to understand the presence and severity of pneumonia and even to predict its outcome. Several marker shave been used, including C-reactive protein (CRP), procalcitonin, several interleukines [IL1, IL6, IL8, IL10], tumor necrosis factor-alpha (TNF alfa), etc, as markers of inflammation /infection, severity, therapeutic failure, severity therapeutic failure and prognostic tool. This review was performed to summarize the observations of the more recent published data on this topic, trying to explore strengths and weaknesses of these markers.

GABA in the central amygdaloid nucleus modulates the electrolyte excretion and hormonal responses to blood volume expansion in rats

We investigated the involvement of GABAergic mechanisms of the central amygdaloid nucleus (CeA) in unanesthetized rats subjected to acute isotonic or hypertonic blood volume expansion (BVE). Male Wistar rats bearing cannulas unilaterally implanted in the CeA were treated with vehicle, muscimol (0.2 nmol/0.2 µL) or bicuculline (1.6 nmol/0.2 µL) in the CeA, followed by isotonic or hypertonic BVE (0.15 or 0.3 M NaCl, 2 mL/100 g body weight over 1 min). The vehicle-treated group showed an increase in sodium excretion, urinary volume, plasma oxytocin (OT), and atrial natriuretic peptide (ANP) levels compared to control rats. Muscimol reduced the effects of BVE on sodium excretion (isotonic: 2.4 ± 0.3 vs vehicle: 4.8 ± 0.2 and hypertonic: 4.0 ± 0.7 vs vehicle: 8.7 ± 0.6 µEq·100 g-1·40 min-1); urinary volume after hypertonic BVE (83.8 ± 10 vs vehicle: 255.6 ± 16.5 µL·100 g-1·40 min-1); plasma OT levels (isotonic: 15.3 ± 0.6 vs vehicle: 19.3 ± 1 and hypertonic: 26.5 ± 2.6 vs vehicle: 48 ± 3 pg/mL), and ANP levels (isotonic: 97 ± 12.8 vs vehicle: 258.3 ± 28.1 and hypertonic: 160 ± 14.6 vs vehicle: 318 ± 16.3 pg/mL). Bicuculline reduced the effects of isotonic or hypertonic BVE on urinary volume and ANP levels compared to vehicle-treated rats. However, bicuculline enhanced the effects of hypertonic BVE on plasma OT levels. These data suggest that CeA GABAergic mechanisms are involved in the control of ANP and OT secretion, as well as in sodium and water excretion in response to isotonic or hypertonic blood volume expansion.

Correlation between D-dimer, N- Terminal pro atrial natriuretic peptide, and left atrial size in patients with chronic nonvalvular atrial fibrillation

In patient with chronic nonvalvular atrial fibrillation [AF], the correlation between prothrombotic marker D-dimer, N-terminal pro-atrial natriuretic peptide [NT-ANP], and left atrial [LA] size is not completely understood also, the precise effect of hypercoagulability is not well known to date. Therefore, this study was performed to determine whether prothrombotic state presented by increase level of D-dimer in patients with chronic nonvalvular AF, as well as NT-ANP were correlated with left atrial size and risk of thromboembolic events. A 43 patients with chronic nonvalvular atrial fibrillation with prior cerebrovascular cardioembolic event and 35 without cardioembolic event were studied for echocardiographic LA size, D-dimer level and NT-ANP. the LA size and D-dimer were significantly high in patients with cardioembolic stroke than patients without cardioembolic stroke [P value <0,05], no significant difference in NT-ANP in both groups [P value >0.05], a positive linear correlation was found between the increased D-dimer level and LA size [r=0.42, P<0.01]. No correlation was found between NT-ANP level and the LA size. the present study concluded that the prothrombotic marker D-dimer is elevated in patient with chronic nonvalvular AF, this marker showed positive linear correlation to the left atrial size and cardioembolic risk of stroke making it a significant marker for risk stratification for those patient whom at high risk, the result also opened a rational for use of warfarin in those patient with elevated D-dimer

neuro - cardiac hormone B- type natriuretic peptide [B.N.P] and cardiac dysfunction

B-type natruretic peptide [B.N.P] is cardiac neurohornone specifically secreted from the ventricles in response to volume expansion and pressure overload. Levels of [B.N.P] are elevated in patients with left ventricular dysfunction. B.N.P testing is best used as a rule out test, for suspected cases of new heart failure in breathless patients. as a matter of fact it is not a replacement for echocardiography and full cardiological assessment. which will be required for patients with an elevated BNP concentration. B.N.P levels rise with age and are affected by gender, drug therapy such as diuretics, beta-blockers and renal failure, it can not stand alone as a diagnostic test, physical examination and chest X-ray and ECG should be globically studied. The importance of this study in heart failure practice are: diagnosis, screenings of asymptomatic left ventricular dysfunction, risk stratification, prognostification, and treatment monitoring

Effects of serum from crush injury rats on vascular endothelial cell apoptosis and their potential mechanism / 法医学杂志

OBJECTIVE@#To investigate the effects of serum from crush injury rats on vascular endothelial cell apoptosis and their potential mechanism.@*METHODS@#Bovine aorta endothelial cells were cultured in vitro and the effects of serum from crush injury rats on cell apoptosis and intracellular calcium concentration ([Ca2+]i) were observed. Meanwhile, the levels of rat blood plasma endothelin-1 (ET-1) and atrial natriuretic peptide(ANP) were measured.@*RESULTS@#Compared with normal rat serum treatment, the cell apoptosis rate decreased from (8.26+/-1.75)% to (2.75+/-0.90)%, while the concentration of [Ca2+]i increased from (96.98+/-3.95) to (118.79+/-3.22) nmol/L in serum from crush injury rats, respectively. The concentration of ET-1 and ANP increased significantly in crush injury rat serum.@*CONCLUSION@#Serum from crush injury rats could inhibit apoptosis of the vascular endothelial cells. These effects may be related to increased level of [Ca2+]i mediated by ET-1 and ANP.

Plasma natriuretic peptides as predictors of hemodynamically significant patent ductus arteriosus in preterm neonates

The objective of this study was to determine whether the plasma levels of natriuretic peptides in preterm infants with patent ductus arteriosus [PDA] are predictors of the hemodynamic significance of the PDA shunt, and correlate them with clinical and echocardiographic assessment. Fifty preterm neonates, with a mean gestational age of 29.4 wk and weighing less than 1500 g, were enrolled in the study. Based on the clinical and echocardiographic findings, the hemodynamic influence of PDA shunt was classified as: large [8 infants], moderate [10 infants], small [12 infants] or no PDA [20 infants]. Plasma N-terminal atrial natriuretic peptide prohormone [Nt-pro ANP] and brain natrituretic peptide [BNP] were assessed using ELISA kits. The results showed that plasma levels of Nt-pro ANP and BNP significantly increased with the size of PDA shunt, and when compared to infants without PDA [P<0.05]. A value of Nt-pro ANP > 5000 pmol/l predicted a hemodynamically significant PDA with a sensitivity of 97% and a specificity of 90%, whereas a value of BNP > 25 pmol/l had a sensitivity of 87% and a specificity of 75%. Using echocardiographic left atrial/aortic root ratio [LA: Ao ratio] of 1.5 as a cut off gave a sensitivity of 75%. Using echocardiographic left atrial/aortic root ratio [LA: Ao ratio] of 1.5 as a cut off gave a sensitivity of 80% and a specificity of 95%. There were significant positive correlations between these studied parameters [P<0.01]. Plasma naturiuretic peptides [Nt-pro ANP and BNP] can be used as predictors of the hemodynamic significance of PDA in preterm neonates, and their measurement may be regarded as complementary to echocardiography in the assessment of PDA shunt and institution of appropriate treatment. Nt-pro ANP is more sensitive and specific predictor than BNP

Study of some hormonal changes in children with acute hypoxemic respiratory failure, before and during mechanical ventilation

Acute hypoxemic respiratory failure [AHRF] is one of the commonest life-threatening conditions encountered in children. This study was designed to investigate plasma atrial natriuretic peptide [ANP] and endothelin-1 [ET-1] levels in children with AHRF before and after mechanical ventilation [Mv], to clarify their relationship to hemodynamic parameters as well as to assess their prognostic value. Twenty children with AHRF [12 males and 8 females, aged 2 months to 5 years] and ten age-and gender-matched healthy controls were enrolled in this study. Plasma immunoreactive ANP and ET-1 levels were measured just before and one hour after stabilization on MV with pressure controlled ventilation [PCV] and compared with hemodynamic [HR, MBP and CVP] parameters. Blood gas analysis, serum sodium, potassium; urea, creatinine and urine output, sodium and creatinine were measured. Results, Baseline plasma ANP and ET-1 levels were significantly higher in patients than controls, and significantly decreased after stabilization on MV. Early changes of hemodynamics [increased HR and MBP; decreased CVP] and respiratory mechanics [increased MAP; decreased C[DL]] were reversed on MV. Gasometric changes [decreased pH, PaO[2] and PaO[2]/FiO[2], increased PaCO[2] were significantly improved on MV with no effect on PaO[2]/Fio[2] ratio. The initial low serum sodium and potassium levels increased significantly after MV. Mechanical ventilation led to impairment in renal function and reduction in urinary output and sodium excretion. Compared with survivors [n=6], non survivors [n=14] had higher plasma ET-1 and MAP values and lower PaO[2]/FiO[2] ratio. Plasma ANP levels correlated positively with ET-1 levels, MBP, PaCO[2] and negatively with PaO[2]/FiO[2] ratio. Plasma ET-1 levels correlated positively with MAP and negatively with PaO[2]/FiO[2], Plasma ANP and ET-1 levels were markedly increased in children with AHRF and decreased with MV. ET-1 levels will have significant impact on mortality in AHRF. AHRF, acute hypoxemic respiratory failure; ANP, atrial natriuretic peptid ET-1, endothelin4; MV, mechanical ventilation; PCV, positive controlled ventilation; HR, heart rate; MBP, mean arterial blood pressure, CVP, central venous pressure; ABG, arterial blood gases, PaO[2] and PaCQ[2], arterial oxygen and carbon dioxide tensions PaO[2]/FiO[2],ratio of arterial oxygen tension to fraction of inspired oxygen; VT, tidal volume; PEEP, positive end-expiratory pressure; PIP, peak aspiratory pressure; MAP, mean airway pressure; CDL, dynamic lung compliance

Pressão arterial e concentração plasmática do peptídeo atrial natriurético e do peptídeo natriurético tipo B, em gestações complicadas pela pré-eclâmpsia / Influence of atrial natriuretic peptide and type B natriuretic peptide plasma levels on arterial pressure in pregnancies complicated by preeclampsia

OBJETIVO: o estudo busca determinar a existência de associação entre a elevação da pressão arterial e os níveis plasmáticos dos peptídeos natriuréticos ANP e BNP, na gestaçäo complicada pela pré-eclâmpsia. MÉTODOS: em estudo transversal caso-controle, pareado por idade gestacional, 25 grávidas normotensas e 61 portadoras de pré-eclâmpsia foram avaliadas quanto ao nível da pressão arterial e às concentraçöes plasmáticas dos peptídeos natriuréticos ANP e BNP. Exames clínico e laboratoriais foram realizados para o diagnóstico de pré-eclâmpsia, sendo a pressäo arterial medida de forma näo invasiva. As dosagens hormonais foram obtidas por radioimunoensaio, após extraçäo em colunas Sep-pak C18. Os valores médios das concentraçöes plasmáticas do ANP e BNP foram comparados entre grupos com pressäo arterial progressivamente maiores. A correlaçäo entre os valores da pressäo arterial e os níveis plasmáticos do ANP e BNP no sangue materno foi também investigada pela de análise de regressäo no grupo completo de gestantes e em grupos específicos excluindo-se a hipertensäo anterior à gestaçäo e, em seguida, excluindo-se aquelas sem hipertensäo prévia. RESULTADOS: os valores plasmáticos de ANP foram 41.5±7.3, 78.4±13.1 e 89.2±13.4 pg/mL (p<0,00001) e os de BNP plasmático foram 79.5±15.8, 176.7±42.2 e 208.3±63.5 pg/mL (p=0,005), respectivamente, para os grupos de pressäo arterial média =107 mmHg, 107-139 mmHg e =140 mmHg. Verificou-se correlaçäo positiva entre as concentrações plasmáticas do ANP e os níveis pressóricos na pré-eclâmpsia, independente da existência de estado hipertensivo prévio à gestaçäo (p<0,0001 para pré-eclâmpsia e p<0,01 para pré-eclampsia sobreposta à hipertensäo arterial crônica), ao passo que as dosagens de BNP näo se mostraram associadas à pressão arterial no grupo com hipertensäo arterial prévia à gestação (p=0,004 para pré-eclâmpsia e p=0,18 para pré-eclampsia sobreposta à hipertensäo arterial crônica). CONCLUSÃO: o agravamento da hipertensäo na pré-eclâmpsia correlacionou-se com as concentraçöes séricas do ANP e BNP, embora os valores do BNP possam ser influenciados pela existência de estado hipertensivo prévio

B-Type Natriuretic Peptide Predicts Clinical Presentations and Ventricular Overloading in Patients with Heart Failure

Brain natriuretic peptide (BNP), a neurohormone secreted from the ventricular myocardium in response to hemodynamic load/wall stress, in congestive heart failure (CHF). This study was performed to evaluate the correlation between BNP level and clinical presentations and hemodynamic parameters obtained by echo-Doppler (echo-Doppler) analysis, and its relation with disease severity and ventricular load/wall stress. CHF patients (n=246) were subgrouped by clinical presentations and echo-Doppler findings into 4 groups: diastolic HF only, chronic HF, acute HF, and chronic HF with acute exacerbation. A BNP level of 81.2 pg/ml showed a sensitivity/ specificity of 53.3%/98.4% for detecting CHF (AUC, 0.882; p< 0.0001), and was found to be closely related with the NYHA classification (p< 0.0001). Log BNP was related with LVEF (r2=0.3015, p< 0.0001) and the Meridional wall stress index (r2=0.4052, p< 0.0001). The difference between the BNP levels of the subgroups and BNP control was significant (p< 0.0001), exept between the HF group and the controls; control (n=114, 20.9 +/- 31.4pg/ml), only diastolic HF (n=84, 89.8 +/- 117.6pg/ml), chronic HF (n=60, 208.2 +/- 210.2pg/ml), acute HF (n=28, 477.9 +/- 498.4 pg/ml), chronic HF with acute exacerbation (n= 74, 754.1 +/- 419.2pg/ml). The BNP level was significantly higher in the only diastolic HF group than in the asymptomatic control group with diastolic dysfunction (89.8 +/- 12.8 vs. 22.8 +/- 5.1pg/ml, p< 0.0001). BNP may be a good indicator for the differential diagnosis of a broad spectrum of heart failures. And, elevated BNP might help to diagnose diastolic HF in patients with diastolic dysfunction.

Relação das pressões atriais com o peptídio natriurético atrial e seus efeitos na diurese e natriurese durante operação cardíaca com circulação extracorpórea / Variations of the atrial natriuretic peptide (ANP) introduced by estracorporeal circulation (ECC) during cardiac surgery

OBJETIVO: Estudar as variações do peptídio natriurético atrial (PNA) introduzidas pela circulação extracorpórea (CEC) durante operação cardíaca e testar a hipótese de que existe correlação entre os níveis plasmáticos de PNA, pressão atrial direita (PAD) pressão atrial esquerda (PAE), diurese e natriurese. MÉTODO: Estudo de coorte de 15 pacientes submetidos a revascularização do miocárdio com CEC. Os intervalos de tempo de observação foram: t0 = 10 minutos antes da CEC (valor controle); t1 = 10 minutos depois de fluxo total em CEC; t2 30 minutos em fluxo total em CEC; t3 = fase final da CEC em temperatura nasofaringeana de 36º C; e t4 = 30 minutos após o término da CEC. RESULTADOS: Os valores do PNA, PAE e PAD variaram significativamente (p<0,001). O PNA diminuiu de t0 para t1 (NS) e após elevou-se progressivamente até t4 (p<0,001). A PAE e a PAD reduziram (p<0,001) entre t0 e t1, elevando-se progressivamente até t4 (p<0,001). O Na+ urinário aumentou entre t0 e t3 (p<0,001), com queda em t4. A diurese aumentou progressivamente em todos os tempos considerados (p<0,001). Foi encontrada correlação significativa entre PNA e o volume de diurese no t0, coeficiente de correlação de 0,535 (p=0,040), e no tempo igual a t2 entre PNA e PAD, coeficiente de correlação de 0,590 (p=0,021). CONCLUSÃO: As concentrações do PNA apresentam variações durante a operação de revascularização com CEC, o que favorece o conceito de estar relacionadas com as pressões atriais, e ao término da CEC, têm uma importante função na excreção de sódio e no volume da diurese