Abstract 12295: Thrombosis and Risk for Mortality among Children with Single Ventricle Physiology Following Initial Palliative Surgery
Introduction: Thromboembolism in children with congenital heart disease is a major cause of morbidity and mortality. Although surgery for single ventricle physiology is associated with an increased risk for thrombosis, little is known concerning the epidemiology of thrombosis in this cohort. Hypothesis: Among single ventricle physiology patients undergoing an initial palliation, the incidence and sequelae of postoperative thrombosis is greater in patients with systemic right ventricles (sRV) compared to patients with systemic left ventricles (sLV).
Methods: Records of all patients with single ventricle physiology from November 2006 to November 2011 were reviewed. Incidence and anatomic location of thrombosis occurring in the inter-stage period following palliation was noted. Diagnosis of thrombus was made by ultrasound imaging, angiography, or direct inspection in the operating room or at autopsy.
Results: Of 263 patients, 131 (50%) had a sRV and underwent Norwood surgery (100 with BT shunt, 31 with RV to pulmonary artery shunt), and 132 (50%) had a sLV (105 with isolated BT shunt, 27 with pulmonary artery banding). The overall incidence of thrombosis was 22% (8% arterial, 15% venous, and 3% intra-cardiac) and was greater in sRV patients relative to sLV patients (30% v.14%, p=0.003). Patients with thrombosis had increased mortality compared to those without thrombosis (24% v. 12%, p=0.01, OR 2.4), but the increased mortality was driven entirely by the sLV subgroup (29% v. 5%, p< 0.001, OR: 9.7). Interestingly, thrombosis did not affect mortality in the sRV subgroup. Subgroup analysis in sRV patients demonstrated no difference in thrombosis or inter-stage mortality between BT shunt and RV to pulmonary artery shunt.
Conclusion: Children with single ventricle physiology undergoing palliation surgery have a high incidence of thrombosis, particularly those with systemic right ventricles. Among systemic RV patients, thrombosis was not associated with type of shunt. Thrombosis was associated with increased mortality in sLV patients only, suggesting that other factors contribute to increased mortality in sRV patients.
- © 2012 by American Heart Association, Inc.