The pulmonary arterial system, an anatomic/MRI study in sagittal planes

Abstract

This paper provides a description and a mini-atlas (with bold labeled anatomic drawings and magnetic resonance images (MRIs) of the pulmonary arterial system and surrounding structures for the purpose of interpreting MRIs of heart patients examined in sagittal planes. The pulmonary arterial system (right outflow tract) was studied by examination of cadaver sections made in sagittal planes and by examination of corresponding MRIs from two living normal adult males. We propose a nontraditional format for describing the pulmonary arterial system by dividing it into four parts, rather than the customary three parts, adding apulmonaq vuhe region between the ending of the conus arteriosus and the beginning of the pulmonary trunk. This region contains the entire pulmonary valve. It is approximately 1.5 cm long and is defined or outlined by the triple-scalloped fibrous annulus of the pulmonary valve as described by Zimmerman (Ann R Coll Eng39:348, 1966). Defining chis region as a separate anatomic entity provides for a more precise description of the relationships of the left coronary and anterior interventricular arteries, the left sinus of the aortic valve, and the left auricle to the outflow tract than that found in conventional descriptive anatomy. This paper also defines the ending of the pulmonary trunk, and the orifices of the left and right pulmonary arteries in relationship to the carina found in the upper posterior wall of the pulmonary trunk. An explanation for preferential enlargement of the left pulmonary artery in pulmonary valve stenosis is correlated to our study. 0 1992 WiIey-Liss, Inc.