Transcatheter management of residual shunts after initial transcatheter closure of a patent arterial duct.

Objectives: To assess the efficacy and safety of transcatheter reocclusion of persistent leaks following previously attempted transcatheter occlusion of persistent arterial duct.
Design: Retrospective study.
Setting: Tertiary pediatric cardiology centre.
Patients: From February 1987 through October 1996, trans-catheter occlusion of a residual ductal shunt was attempted in 42 consecutive patients at a median age of 5.0 years (range 1.6 years to 16.2 years).
Interventions: Fourty patients had successful placement of a double umbrella occluder (n=27) or coils (n=13) across residual shunts. Complications included device embolization in two patients and hemolysis in one patient.
Outcome Measures and Results: Mean z-score for left ventricular end-diastolic dimension (LVEDD) at initial echocardiography was +2.55 +/- 1.89 (P<0.0001 versus normal); z-score for left pulmonary artery (LPA) diameter was +2.00 +/- 1.52 (P<0.0001). Mean LPA to right pulmonary artery (RPA) diameter ratio was 1.05 +/- 0.18. At follow-up echocardiogram, a median of two years (range six months to 7.7 years) after the second procedure, a shunt was persistent in 3% of the patients. Mean LVEDD and LPA diameter z-value, and mean LPA to RPA diameter had dropped significantly to +0.42 +/- 1.31, +0.07 +/- 1.15 and 0.86 +/- 0.14 (P<0.001), respectively. LPA flow acceleration was present in 25% of patients. Three of nine patients, in whom lung perfusion scan was performed, had left lung perfusion below 40%. Small weight and age at catheterization were significant risk factors for LPA flow disturbance.
Conclusions: Repeat transcatheter occlusion is safe and successful in eliminating residual shunt across the arterial duct. Attention should, however, be addressed to the potential for LPA stenosis and growth, and flow should be regularly assessed.