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.