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

Abstract

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 (R 2 = 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.

Doppler Ultrasonographic Assessment of Abdominal Aortic Flow to Evaluate the Hemodynamic Relevance of Left-to-Right Shunting Patent Ductus Arteriosus in Dogs

“…This could be especially valuable in the absence of secondary cardiac remodeling. In fact, the dilation of the left atrium and ventricle as a response to the volume overload is reported as gradual and progressive and the time of exposure as a factor influencing the evaluation of the hemodynamic significance of a PDA [29,30]. In the present study, a retrograde pattern was observed in a 3-month-old dog included in the non-hsPDA group, suggesting systemic hypoperfusion and possible misclassification if measurable cardiac remodeling had not occurred yet at the time of presentation.…”

Ductus arteriosus and the preterm brain

“…Echocardiographic criteria for an hsPDA typically are based on measures of ductal characteristics, pulmonary overcirculation, systemic hypoperfusion and left ventricular dysfunction,7 which as previously described may be antecedents to cerebral ischaemia and subsequent IVH. Reversal or absence of diastolic flow in the descending aorta in particular has been strongly correlated with PDA shunt volume and abnormal end-organ blood flow, including significant correlation with flow reversal in the coeliac artery (relative risk (RR) 4.3; 95% CI 2.4 to 7.4), but not in the middle cerebral artery (RR 1.4; 95% CI 0.3 to 8.5) 8. An example of diastolic flow reversal by echocardiogram and normalisation of this pattern after ductal closure is shown in figure 2.…”