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Incidence and impact of systemic venous collateral development after Glenn and Fontan procedures.

BACKGROUND
Development of systemic venous collaterals after Glenn or Fontan procedures can lead to systemic desaturation and reduction in ventricular function, resulting in impaired everyday performance in patients with univentricular heart disease.


METHODS
We analyzed 79 patients who had undergone a Glenn or Fontan procedure between 1995 and 1999 for the incidence and predilection sites of systemic venous collaterals as well as the therapeutic options.


RESULTS
In 16/79 (= 20.2%) patients, 19 veno-venous connections were detected 310 days (1-966 days) postoperatively. Locations were: brachiocephalic angles/pericardial veins (7), azygos/hemiazygos system (5), Thebesian veins (2), epidiaphragmatic veins (5). Drainage was to the pulmonary veins in 5, to the "left" atrium in 9, and to the IVC system in 5 patients. An isolated intervention became necessary because of low saturations in 5/16 pts, with improvement in all of them (catheter embolization 4, surgical closure 1).


CONCLUSIONS
After Glenn or Fontan operations, the increased central venous pressure may induce recanalization of embryologically preformed and obliterated vessels. Their predilection sites must be carefully evaluated pre- and postoperatively. During surgical procedures, potential venous channels should be ligated. Interventional or surgical closure of collaterals may become necessary.