Abstract
The various components of the pulmonary venous (PV) flow are linked to physiological and pathological changes that predominantly occur in the left heart. Thus, spectral Doppler interrogation of the PVs provides hemodynamic insight mainly into left-sided cardiac function. An exception to the dependence of PV flow on left heart events occurs in the setting of an atrial septal defect (ASD). The latter causes a portion of the PV blood flow, intended to cross the mitral valve, to be channeled into the more compliant right heart. This phenomenon makes the PV flow more dependent on the left-to-right interatrial shunt. The identification on the PV Doppler of a pattern that suggests uncoupling with left heart hemodynamics should raise the suspicion of an underlying ASD.