Wall motion characteristic of the right pulmonary artery in the suprasternal echocardiogram

This study describes the motion pattern of the right pulmonary artery (RPA) as it can be assessed from the suprasternal echocardiogram. The motion characteristic of the RPA is dependent on hemodynamic factors within the lumen of the RPA and those within the left atrium and the aortic arch. During atrial contraction the superior wall of the left atrium separates from the inferior wall of the RPA (IWRPA) and produces an "a" dip in the wall motion of the IWRPA. During isovolumic contraction the RPA is shifted upward (IC point). The incisura in the pulmonary artery pressure curve reflecting pulmonic valve closure can be seen by a sudden decrease in the diameter of the RPA (PC point). In conditions coinciding with pulmonary arterial hypertension, the overall diameter of the RPA increases, and the IC and PC points are flattened or even absent. Thus, changes in hemodynamics caused by pulmonary or cardiac disease may be analyzed noninvasively on the basis of altered wall motion of the RPA.