Interrelationship of architecture and function of the right ventricle.

ARMOUR, J. A., J. B. PACE, AND W. C. RANDALL. kWreZationship of architecture and function uf the right ventricle. Am. J. Physiol. 2N3(1): ,)174-179. 1970.-The sequence of contraction and augmentation patterns in contractile force of the sinus and conus regions of the right ventricle were analyzed under control, vagal, and sympathetic stimulation as well as norepinephrine infusion states. The normal peristaltic contraction wave from sinus to conus was exaggerated during vagal stimulation but made more nearly synchronous or even abolished during stellate ganglion stimulation. The sinus to conus sequence was often reversed as a result of norepinephrine augmentation. Whereas the conus fibers showed greater increase in force of contraction than did the sinus fibers during stellate stimulation and norepinephrine injection, pressures recorded from the sinus portion of the right ventricle greatly exceeded those measured simultaneously from the conus. A marked intraventricular pressure gradient was created from sinus to conus, with a relatively smaller gradient from conus to pulmonary artery. Thus, the functional intervention of the infundibular region of the right ventricle as a pressure regulator protecting the pulmonary vasculature may be hypothesized.