Relationship of Patent Ductus Arteriosus Echocardiographic Markers With Descending Aorta Diastolic Flow.

OBJECTIVES: To characterize the relationship of echocardiographic markers of left heart overload and flow in peripheral major end-organ vessels (eg, celiac artery) with the presence of reversed holodiastolic flow in the descending aorta, considered a surrogate marker of an increased transductal shunt volume, in preterm patients with a patent ductus arteriosus (PDA). METHODS: This work was a retrospective study of data from echocardiography performed to investigate the hemodynamic significance of a PDA in preterm patients. We studied differences in echocardiographic markers of the PDA shunt volume according to patterns of flow in the postductal descending aorta (no PDA, PDA with antegrade diastolic flow, and PDA with reversed diastolic flow). The strength of the association between each echocardiographic marker and the presence of aortic holodiastolic flow reversal was investigated. RESULTS: We studied 137 patients with a median (interquartile range) birth weight of 850 (694-1030) g and a median gestational age of 25 (24-27) weeks. Among patients with a PDA (113), those with diastolic flow reversal in the descending aorta (44) presented had increased echocardiographic markers representative of the shunt volume (increased left ventricular output, left atrial-to-aortic ratio, pulmonary vein D wave, and shorter isovolumic relaxation time) compared to those with aortic antegrade diastolic flow. A positive, albeit weak, correlation between diastolic flow reversal and shunt volume echocardiographic markers was found. Abnormal diastolic flow in the celiac artery had the strongest correlation (R2  = 0.24). CONCLUSIONS: In preterm patients with a PDA, echocardiographic markers of the shunt volume were more abnormal in patients with reversed diastolic flow in the descending aorta. These data support the assumption that variance in these markers are related to the shunt volume, which needs consideration when adjudicating hemodynamic significance.

Use of sildenafil for pulmonary hypertension in neonates.

Pulmonary arterial hypertension is a multifactorial nosological entity that increases neonatal mortality as a result of heart failure. Pulmonary vasodilators are the cornerstone of treatment, of which sildenafil is the most commonly used drug. Therefore, the results of a recently updated Cochrane systematic review are summarized, in which the efficacy and safety of sildenafil for the treatment of pulmonary hypertension in neonates was evaluated.

La hipertensión arterial pulmonar es una enfermedad multifactorial que incrementa la mortalidad en el neonato como consecuencia de falla cardiaca. Los vasodilatadores pulmonares son la piedra angular del tratamiento, de los cuales el ­sildenafil es el fármaco más empleado. A continuación, se resumen los resultados de una revisión sistemática Cochrane en la que se evaluaron la eficacia y la seguridad del sildenafil para el tratamiento de la hipertensión arterial pulmonar en neonatos.

The Relationship between blood pressure parameters and left ventricular output in neonates.

OBJECTIVE: To evaluate the relationship between systolic (SBP), diastolic (DBP), mean (MBP) blood pressures and pulse pressure (PP), and left ventricular output (LVO), a surrogate of systemic blood flow. STUDY DESIGN: This retrospective study included neonates who underwent targeted neonatal echocardiography (TNE) in 3-tertiary NICUs over 2 years. Associations between LVO and BP components were investigated. Analysis was adjusted for relevant covariates. RESULT: 1060 studies from 485 neonates were included, with a mean GA of 28.4 ± 4.6 weeks and birth weight of 1234 ± 840 grams. LVO was associated positively with SBP and PP, and negatively with GA. PP demonstrated the highest predictive value for identifying infants with LVO < 150 ml/kg/min (area under the curve 0.75 [95% CI 0.68, 0.82]). MBP and DBP demonstrated no correlation with LVO. CONCLUSION: BP parameters correlate poorly with LVO, irrespective of GA and underlying etiology. Narrow PP may be more reflective of low LVO than low SBP.