Background The Pediatric Heart Network trial comparing outcomes in 549 infants with single right ventricle (RV) undergoing a Norwood procedure randomized to modified Blalock-Taussig shunt (MBTS) or right ventricle-to-pulmonary artery shunt (RVPAS) found better one-year transplant-free survival in those who received RVPAS. We sought to compare the impact of shunt type on echocardiographic indices of cardiac size and function up to 14 months of age. Methods and Results A core laboratory measured indices of cardiac size and function from protocol exams: early after Norwood (age 22.5±13.4 days), before stage II procedure (age 4.8±1.8 months) and at 14 months (age 14.3±1.2 months). Mean RV ejection fraction was <50% at all intervals for both groups and was higher in the RVPAS group post-Norwood (49±7 vs. 44±8%, P<0.001), but was similar by 14 months. Tricuspid and neo-aortic regurgitation, diastolic function, and pulmonary artery and arch dimensions were similar in the two groups at all intervals. Neo-aortic annulus area (4.2±1.2 vs. 4.9±1.2 cm2/m2), systolic ejection times (214.0±29.4 vs. 231.3±28.6 msec), neo-aortic flow (6.2±2.4 vs. 9.4±3.4 L/min/m2), and peak arch velocity (1.9±0.7 vs. 2.2±0.7 m/sec) were lower at both interstage exams in RVPAS compared to MBTS (P<0.001 for all), but all were similar at 14 months. Conclusion Indices of cardiac size and function after the Norwood procedure are similar for MBTS and RVPAS by 14 months of age. Interstage differences between shunt types can likely be explained by the physiology created when the shunts are in place rather than by intrinsic differences in cardiac function. Clinical Trial Registration # NCT00115934, URL: http://clinicaltrials.gov/ct2/show/NCT00115934

We document the presentation profiles, treatment strategies, and clinical outcomes in a relatively large cohort of pediatric patients with intracardiac thrombi (ICT). We performed a retrospective review of patients diagnosed with ICT by echocardiography at a tertiary pediatric hospital during a 10-year period. These patients received medical therapy or thrombectomy. We provided echocardiographic descriptions of the ICT-size, chamber location, and mobility/morphology. The outcome measures were ICT (persistence, resolution, or embolization), effectiveness of therapy, and patient morbidity and mortality. There were 40 ICT diagnosed in 31 patients (22 males and 9 females). Mean age at diagnosis was 8.8 years (range, 15 days to 18 years). Overall mortality was 12/31 patients (39%); only one death was attributed to ICT embolization. Embolic events occurred in 4/31 patients (13%). The most common initial therapies included heparin infusion (n = 15), warfarin (n = 7), and aspirin (n = 7). The ICT resolved with medical therapy alone in 19/30 patients (63%). One patient required surgical thrombectomy. The cohort was divided into group 1 (dilated cardiomyopathy), group 2 (status post Fontan operation), and group 3 (other diagnoses). In group 1 (n = 11), there were 8 deaths. Embolization occurred in 2/5 large ICT, resulting in cerebral infarction and death (n = 1) and renal infarction (n = 1). The most common ICT location was the left ventricle (n = 10). Severe ventricular systolic dysfunction was present in 10/11 patients (91%). In group 2 (n = 9), there was 1 death. Embolization occurred in 1/7 large ICT, resulting in seizures and temporary paresis. All ICT were located in the Fontan pathway. Severe ventricular systolic dysfunction was present in 2/9 patients (22%). In group 3 (n = 11), there were 3 deaths. Embolization occurred in 1/9 small ICT, resulting in coronary emboli. ICT are most commonly diagnosed in pediatric patients with dilated cardiomyopathy or patients status post Fontan operation. The majority of ICT resolve with medical therapy. Larger ICT tend to embolize more frequently, and the morbidity secondary to embolization is significant. Rarely is mortality due to ICT embolization. The prognosis is poor for patients with left ventricular ICT or ICT in the presence of ventricular systolic dysfunction.