Pulmonary artery versus left ventricular venting: a radioisotope study of left ventricular function

Radionuclide measurements of ejection fraction were used to assess immediate and late postoperative ventricular function after the use of either a pulmonary artery vent (group A) or a left ventricular vent (group B) in 20 patients undergoing aortic valve replacement for pure aortic stenosis. Ten patients were included in each group and anesthetic techniques, patient management, and septal temperatures were similar in all cases. No significant difference was found between the preoperative and immediate or 6-week postoperative ejection fractions, either taken overall or between the two groups (p greater than 0.05; Student's t test). No correlation was found between cross-clamp time, bypass time, or the occurrence of ventricular fibrillation and the immediate postoperative ejection fraction (p greater than 0.05; Student's t test). There was no significant difference in the incidence of ventricular fibrillation after each type of vent had been used (chi 1(0) = 3.32; p greater than 0.05). We did not demonstrate any abnormalities in regional wall motion associated with apical insertion of a left ventricular vent, and conclude that pulmonary artery and left ventricular vents are equally satisfactory in terms of postoperative ventricular performance.