Factor V Leiden Polymorphism Decreases Blood Loss After Cardiac Surgery
Blood loss is less and the need for transfusion is reduced following cardiac surgery among patients heterozygous for Factor V Leiden (FVL), physicians at Vanderbilt University report in the February 25th issue of Circulation.
Dr. Brian S. Donahue and associates prospectively enrolled 517 adult patients undergoing routine elective cardiac surgery requiring cardiopulmonary bypass.
Among the 26 carriers of FVL, blood loss averaged 238 mL at 6 hours and 522 mL at 24 hours. The volumes lost were significantly greater among noncarriers, 358 and 730 mL, respectively (P < or = 0.001). "The impact of FVL was similar to that of the antifibrinolytic drugs, aprotinin and epsilon-aminocaproic acid," the Nashville, Tennessee-based investigators note. Furthermore, 46.2% of FVL carriers required no transfusions during hospitalization compared with 28.3% of noncarriers (p = 0.051). The effect of FVL on hemostatic outcomes remained an independent predictor in multivariate analyses. “Genetic variability can have an independent, relevant impact on outcome after complex surgical procedures,” Dr. Donahue and his colleagues conclude. Screening patients for Factor V Leiden may help identify patients at higher risk for bleeding complications and “might help predict whether or not you ought to use a prophylactic antifibrinolytic agent,” Dr. Jeffrey R. Balser, chief of the department of anesthesiology at Vanderbilt, told Reuters Health. “The potential for predictability as exhibited by Dr. Donahue’s study is enormous,” he added. Dr. Balser and his associates are developing Vanderbilt as a center for genomics research in perioperative medicine. “We are asking whether common gene sequence variance or polymorphisms are predictive of postsurgical complications,” he explained. For example, they are examining whether postsurgical cardiac arrhythmias or infectious complications can be predicted on the basis of genetic variations, “because there are drugs and interventions that are expensive but potentially useful if we knew ahead of time which patients were at particular risk.” “The field of genomics has looked at the value of gene variation in chronic diseases for several years, but work in the perioperative field is fairly new,” Dr. Balser noted. “The potential benefit to patients is as great or greater in the perioperative venue because millions have surgery every year, and these complications are common and are costly.” Circulation 2003;107:1003-1008.
