NT- Péptido natriurético cerebral en la evaluación de respuesta al tratamiento de la insuficiencia cardíaca con levosimendan en pacientes pediátricos / NT-brain natriuretic peptide in the assessment of response to levosimendan treatment in pediatric patients with heart failure

Introducción: El tratamiento de la insuficiencia cardiaca ha incorporado drogas inotrópicas de muy alto costo, como el levosimendan (LEVO). La evaluación de la respuesta a estas drogas en pediatría ofrece dificultades por lo que la medición de biomarcadores como la prohormona N-Terminal Péptido Natriurético Cerebral (NT-ProBNP) podrían ser de utilidad. Objetivo: describir la variación del NT-ProBNP y su correlación con parámetros ecocardiográficos en respuesta a la administración de levosimendan en pacientes pediátricos con insuficiencia cardiaca. Diseño: estudio descriptivo, observacional y prospectivo, sin intervención. Pacientes y métodos: se incluyeron pacientes con insuficiencia cardiaca de 0 a 18 años internados en terapia intensiva a los cuales se les pudo realizar dosaje de NT ProBNP pre LEVO. Se midió dicho péptido al 1°, 3° y 5° día post LEVO. Con cada determinación se realizó ecocardiograma doppler. Resultados: Se enrolaron 15 pacientes, mediana de edad 188,5 días (IQR 25-75: 56-475); de peso 5,475 kg (IQR 25-75: 2.8-7.5). El 80% fueron pacientes con reparación quirúrgica de cardiopatías congénitas, 13.3% con ventrículo único. La mediana de valor de NT ProBNPantes de la administración de LEVO fue 8924.5 pg./ml (IQR 25-75: 4096-20419,75). El 80% de la población presentó descenso en el valor de pro BNP post LEVO y en 10 (66.6%) el descenso fue mayor o igual al 30%. La evaluación global de la función miocárdica no presentó diferencias antes y después del LEVO. Conclusiones: El 66% de los pacientes presentó una disminución de al menos un 30% en los valores de NT ProBNP luego de la administración de levosimendan

Introduction: Very high-cost inotropic drugs, such as levosimendan (LEVO), have been incorporated in the treatment of heart failure. Evaluation of the response to these drugs in children is difficult and measurement of biomarkers such as the prohormone N-terminal pro b-type natriuretic peptide (NT-proBNP) may be of use. Objective: To describe variation of NT-ProBNP and its correlation with echocardiographic parameters in response to the administration of LEVO in pediatric patients with heart failure. Design: A prospective, descriptive, observational, non-interventional study. Patients and methods: Patients between 0 and 18 years of age with heart failure admitted to the intensive care unit in whom pre-LEVO NT-ProBNP levels could be measured were included. NT-ProBNP levels were measured at day 1, 3, and 5 post LEVO. At each measurement, a Doppler echocardiogram was performed. Results: 15 patients with a median age of 188.5 days (IQR 25-75: 56-475) and a weight of 5.475 kg (IQR 25-75: 2.8-7.5) were enrolled. Of the patients, 80% had undergone surgery for congenital heart defects, 13.3% with a single ventricle. Median NT-ProBNP levels before LEVO administration were 8924.5 pg./ml (IQR 25-75: 4096-20419.75). Overall, 80% of the patients had a decrease of post-LEVO NT-ProBNP levels and in 10 (66.6%) the decrease was greater than or equal to 30%. Overall evaluation of myocardial function did not show differences before and after LEVO administration. Conclusions: 66% of the patients presented with a decrease of at least 30% of NT-ProBNP levels after LEVO administration

Effects of anesthesia on echocardiographic assessment of left ventricular structure and function in rats.

Echocardiography is an essential diagnostic tool for accurate noninvasive assessment of cardiac structure and function in vivo. However, the use of anesthetic agents during echocardiographic studies is associated with alterations in cardiac anatomical and functional parameters. We sought to systematically compare the effects of three commonly used anesthetic agents on echocardiographic measurements of left ventricular (LV) systolic and diastolic function, LV dimensions, and LV mass in rats. Adult male Fischer 344 rats underwent echocardiographic studies under pentobarbital (PB, 25 mg/kg i.p.) (group I, n = 25), inhaled isoflurane (ISF, 1.5%) (group II, n = 25),or ketamine/xylazine (K/X, 37 mg/kg ketamine and 7 mg/kg xylazine i.p.) (group III, n = 25) anesthesia in a cross-over design. Echocardiography was also performed in an additional group of unanesthetized conscious rats (group IV, n = 5). Postmortem studies were performed to validate echocardiographic assessment of LV dimension and mass. Rats in group I exhibited significantly higher LV ejection fraction, fractional shortening, fractional area change, velocity of circumferential fiber shortening corrected for heart rate, and heart rate as compared with groups II and III. LV end-diastolic volume, end-diastolic diameter, and cross-sectional area in diastole were significantly smaller in group I compared with groups II and III. Cardiac output was significantly lower in group III compared with groups I and II. Postmortem LV mass measurements correlated well with echocardiographic estimation of LV mass for all anesthetic agents, and the correlation was best with PB anesthesia. Limited echocardiographic data obtained in conscious rats were similar to those obtained under PB anesthesia. We conclude that compared with ISF and K/X anesthesia, PB anesthesia at a lower dose yields echocardiographic LV structural and functional data similar to those obtained in conscious rats. In addition, PB anesthesia also facilitates more accurate estimation of LV mass.

Doppler flow and echocardiography in functional cardiac insufficiency: assessment of nisoldipine therapy. Results of the DEFIANT-II Study. The DEFIANT-II Research Group.

AIMS: A multicentre, double-blind, placebo-controlled trial was conducted in 542 patients, randomized 7-10 days after myocardial infarction, to study the effect of nisoldipine coat-core (nisoldipine-CC) on exercise after 6 months. Secondary endpoints included exercise-induced ischaemia, left ventricular function measured by Doppler echocardiography, adverse cardiac events and clinical outcome. METHODS AND RESULTS: Patients had reduced left ventricular ejection fraction between 25 and 50%, but no heart failure. Exercise time was not different in the two groups. Nisoldipine-CC prolonged time to 1 mm ST deviation (P = 0.03). There was an effect of nisoldipine-CC of +3.6 cm.s-1 on early peak velocity (P = 0.01) and of -6.2 ms on isovolumic relaxation time (P = 0.005), but no effects on left ventricular volumes or ejection fraction. There was a trend towards reduced mortality (one death in the nisoldipine-CC group vs seven in the placebo group. P < 0.07) and the combined end-point of mortality and cardiac events (P = 0.09). Peripheral oedema occurred in 49 patients assigned to nisoldipine-CC and two assigned to placebo (P < 0.001). There were no differences in non-cardiac events. CONCLUSIONS: Nisoldipine-CC did not improve exercise time but increased time to 1 mm ST deviation, and improved diastolic left ventricular function. It is safe and well tolerated in post-infarction patients with impaired left ventricular function.