Outcome in infants less than 3 kilograms for placement of saphenous venous homografts as systemic-to-pulmonary arterial shunts.

BACKGROUND: Establishing stable and adequate flow of blood to the lungs using a systemic-to-pulmonary arterial shunt in infants with low birth weight may involve significant morbidity and mortality. We reviewed our experience with this procedure in patients weighing less than 3 kilograms. METHODS: Between June, 2002, and June, 2007, we placed systemic-to-pulmonary arterial shunts in 32 infants weighing less than 3 kilograms, the range being 1.8 to 2.86 kg, with a median of 2.5 kg. The median age at placement of the shunt was 8 days, with a range from 2 to 70 days. In 17 patients (53%), the anatomic defects had produced a functionally univentricular heart, while 15 (47%) had defects which permitted staging to biventricular repair. Patients staged to univentricular palliation were much more likely to have a circulation dependent on the arterial duct as compared with those staged to biventricular palliation (p < 0.001). The latter patients tended to have smaller pulmonary arteries, significantly the left pulmonary artery, which has a median diameter of 3.6 versus 2.0 mm, p = 0.01. In all patients a saphenous venous homograft was used as the conduit, its size ranging in diameter from 2.5 to 4 mm, with a median of 3.0 mm. RESULTS: The overall hospital mortality rate for the entire cohort was 6.25%, with 2 patients dying. There was no significant difference between the two groups with regard to length of stay in intensive care or hospital. Follow-up has ranged from 3 months to 4.7 years, with a mean of 2.1 years). Of those with functionally univentricular hearts, 3 have subsequently died, along with 1 patient having a biventricular circulation (p = 0.3). All deaths occurred before takedown of the shunt. A trend toward longer survival was noted in those with biventricular as compared to functionally univentricular circulations (p = 0.06). CONCLUSION: Systemic-to-pulmonary arterial shunts can be constructed safely in infants with biventricular physiology born with low weight. Those having functionally univentricular circulations carry an increased rate of mortality for the period of shunting. Using the saphenous venous homograft permits use of smaller grafts, which does not significantly increase the risk for thrombosis or survival when compared to previous studies using polytetrafluoroethylene grafts.

Anomalous coronary artery with aortic origin and course between the great arteries: improved diagnosis, anatomic findings, and surgical treatment.

BACKGROUND: Anomalous origin of a coronary artery with subsequent coursing between the great vessels is a rare congenital heart defect that may cause myocardial ischemia and sudden death. Because of the fatality rate of this anomaly, many are diagnosed at the postmortem examination, and reports of surgical correction are few. We present our experience with the diagnosis and surgical treatment of this rare coronary anomaly. METHODS: Between June 2003 and August 2005, 9 patients (8 males) were diagnosed with anomalous origin of a coronary artery coursing between the great vessels. The mean age was 12 +/- 5.8 years (range, 4 months to 23 years). Three patients had an intramural origin of the coronary artery. One infant had a single coronary artery and was diagnosed during follow-up of other heart defects. The 8 older patients all presented with exertional syncope or chest pain and echocardiography was used for the initial diagnosis. Six patients had coronary artery reimplantation in the correct aortic sinus, 2 patients had unroofing of the intramural coronary segment, and 1 patient had pericardial patch enlargement of his right coronary artery before reimplantation. One patient, the infant, awaits repair at an older age. RESULTS: No postoperative deaths occurred. The mean hospital stay was 5.5 +/- 1.2 days (range, 4 to 8 days). Three patients had transient ST segment changes during the first 24 hours postoperatively. Follow-up was 4 months to 2.5 years. All patients underwent an exercise myocardial perfusion scan 3 months postoperatively without evidence of myocardial ischemia, and all patients remain clinically well. CONCLUSIONS: Echocardiography imaging of young patients with exertional syncope or chest pain is reliable for the diagnosis of this coronary anomaly. It is surgically correctable; however, individual coronary anatomy may cause the surgical approach to vary. The postoperative outcome is excellent.

Repeat right ventricular outflow tract reconstruction using the Medtronic Freestyle porcine aortic root.

BACKGROUND AND AIM OF THE STUDY: A variety of valve substitutes are used for right ventricular outflow tract (RVOT) reconstruction in children and young adults after previous RVOT surgery that has led to significant pulmonary insufficiency and/or stenosis. Herein, the authors' experience with pulmonary valve replacement (PVR) using a porcine valved conduit late after previous RVOT surgery was reviewed. METHODS: Between August 2002 and April 2005, 31 patients (mean age 14.5 +/- 9.5 years; range: 1.2-33.1 years) underwent PVR using the Medtronic Freestyle porcine aortic root. These patients averaged two prior operations (range: 1-5) for the following diagnoses: tetralogy of Fallot +/- pulmonary atresia (n = 21); persistent truncus arteriosus (n = 5); aortic stenosis (Ross-Konno procedure) (n = 2); pulmonary atresia with intact ventricular septum; (n = 1); congenital pulmonary stenosis (n = 1); and transposition of the great arteries (n = 1). Of these patients, 29 (93.5%) underwent additional procedures at the time of pulmonary valve insertion including: branch pulmonary artery reconstruction (n = 21), atrial septal defect closure (n = 5), ascending aorta replacement (n = 4), pacemaker or defibrillator placement (n = 3), tricuspid valve repair (n = 2), ventricular septal defect closure (n = 2), and other procedures (n = 2). RESULTS: There were no early or late deaths. The mean hospital stay was 8.3 +/- 5.9 days (range: 4-25 days). One patient had a subarachnoid hemorrhage with transient left hemiparesis, and two patients had acute tubular necrosis with temporary dialysis treatment. All patients were well at a mean follow up of 13 +/- 9.3 months (range: 0.5-31 months). Echocardiography showed trivial or no pulmonary insufficiency in 30 patients (96.7%). The calculated mean peak systolic RVOT gradient by echocardiography was 23.4 +/- 7.6 mmHg. CONCLUSION: The Medtronic Freestyle bioprostheses demonstrated excellent short-term results for repeat RVOT reconstruction. This valve's hemodynamic characteristics are comparable to those of homografts, and it is an attractive alternative given the limited availability of homograft valves. A lack of availability in sizes smaller than 19 mm limits use of this valve in pediatric patients, and long-term results remain to be determined.