Graft Occlusion After Deployment of the Aortic Connector Symmetry System: Is Anticoagulation a Necessity?

Forty-one-month follow-up of the Symmetry aortic connector system for proximal venous anastomosis

OBJECTIVE

Results of short- and midterm follow-up studies of the patency rate of the Symmetry aortic connector systems (St Jude Medical, Inc, Minneapolis, Minn) are controversial. Long-term follow-up studies are still lacking (so far, the longest mean follow-up period was 19 months). The aim of our study was (1) to evaluate the patency rate of this device over a longer time-period and (2) to analyze risk factors for graft occlusion.

METHODS

Between November 2000 and July 2003, 76 Symmetry aortic connector systems were implanted in 42 patients. At follow-up, 24 patients with 44 mechanical connectors were studied with 64-slice cardiac computed tomography. Eight patients had died previously, 6 patients refused to undergo a computed tomographic scan, and 4 patients had to be excluded because of impaired renal function.

RESULTS

From a total of 44 mechanical connectors studied, 24 (55%) were occluded, 20 (45%; confidence intervals 31%-61%) were patent, and 7 of these grafts showed stenosis in the area of the connector. Mean follow-up was 41 +/- 10 months (18-52 months). Sex, age, left main stenosis, hyperlipidemia, hypertension, renal failure, target vessel, stenosis of the target vessel, diameter of the target vessel, type of surgical intervention, diabetes, ejection fraction, postoperative anticoagulation regimen, and the connector size showed no significant influence on the bypass graft patency (P > .05). The bypass graft flow was recognized to be the only risk factor for bypass graft occlusion (P = .0256).

CONCLUSION

Midterm follow-up data show a high number of occluded Symmetry aortic connector system vein grafts. On the basis of these observations, the use of the connector was abandoned at our institution.