DOES GALLSTONE FORMATION AFTER OPEN CARDIAC-SURGERY RESULT ONLY FROM LATENT HEMOLYSIS BY REPLACED VALVES

Objectives: To clarify the relationship between open heart surgery and gallstone formation. Methods: Fifty-one patients without gallstones ( Group A) underwent cardiac surgery using a heart-lung machine and were followed for 24 months by ultrasonography. Blood tests of hemolysis m arkers were examined before, immediately after, and 3, 6, and 12 month s after surgery, And 52 healthy candidates without gallstone (Group B) also were followed for 24 months. Results: The cumulative gallstone i ncidence in Group A was 15.7% at 3 months after surgery, 23.9% at 6 mo nths, and 30.4% at and beyond 12 months and was significantly higher t han that of Group B (p < 0.01). The stones showed a high dense pattern , indicative of pigment stones, in eight of the 10 patients assessed b y CT. With respect to the type of surgery, latent hemolysis was seen o nly in patients who underwent mechanical valve replacement. However, t here were no significant differences in the gallstone incidence betwee n the patients who underwent mechanical valve replacement and those wh o underwent another cardiac surgery. The values of hemoglobin, haptogl obin, and lactate dehydrogenase showed abnormal values immediately aft er surgery, regardless of mechanical valve replacement or another card iac surgery. Conclusions: The use of a heart-lung machine, which produ ces hemolysis, appears to have a close relation to gallstone formation after open cardiac surgery.