Respiratory Hemodynamics in the Hepatic Veins—Normal Pattern

Abstract

Doppler interrogation of blood flow in the hepatic veins (HVs) is a part of any comprehensive echocardiographic examination. Data derived from the HV Doppler provide a useful tool for the assessment of right heart function. Beyond its dependence on the cardiac cycle, right heart hemodynamics, and compliance of the liver parenchyma, blood flow in the HVs is influenced by the respiratory cycle. Systematic analysis of the behavior of the HV Doppler during respiration allows one to recognize normal and abnormal flow-patterns and distinguish among various disease states that involve the right heart. In this manuscript we discuss the effect of respiration on the HV Doppler in individuals with normal right heart function.

Respiratory Hemodynamics in the Hepatic Veins—Abnormal Patterns

“…[1][2][3] Additionally the respiratory cycle exerts some influence on HV flow pattern. [4][5][6] Due to a decrease in intrathoracic pressure, inspiration results in a physiological increase in the forward flow velocities. To the contrary, expiration leads to a decrease in forward flow and increase in flow reversal.…”

“…To the contrary, expiration leads to a decrease in forward flow and increase in flow reversal. [4][5][6] Most disease states that involve the right heart affect the HV Doppler in a manner independent of the respiratory cycle. 3 Therefore, neither inspiration nor expiration alters the HV flow in a cycle-specific manner.…”

“…3,6 When abnormal compliance exists, the stiff RV is unable to accommodate the volume load caused by inspiration thus leading to an abnormal increase in filling pressures. 3,6 The HV Doppler demonstrates a restrictive pattern characterized by prominent diastolic flow reversals during inspiration. 8,9 A normal filling pattern, i.e., no exaggerated reversals in the HV, may coexist with normal or elevated right atrial (RA) pressure when RV and pericardial compliance are normal.…”

“…Blood flow in the hepatic veins (HVs) is tightly tied to the cardiac cycle and right heart hemodynamics . Additionally the respiratory cycle exerts some influence on HV flow pattern . Due to a decrease in intrathoracic pressure, inspiration results in a physiological increase in the forward flow velocities.…”

Spectral Doppler of the Hepatic Veins in Noncardiac Diseases: What the Echocardiographer Should Know

“…6). [14][15][16][17] Some disease states that involve the right heart affect the HV Doppler in a manner dependent on the respiratory cycle. 11,18 Thus, analysis of the HV Doppler should include an assessment of the respiration-dependent filling pattern of the right heart.…”