Comparison Between Bench-Top and Computational Modelling of Cerebral Thromboembolism in Ventricular Assist Device Circulation.

Despite improvements in ventricular assist devices (VAD) design, VAD-induced stroke rates remain remarkably high at 14-47%. We previously employed computational fluid dynamics (CFD) to propose adjustment of VAD outflow graft (VAD-OG) implantation to reduce stoke. Herein, we present an in-vitro model of cerebral vessel embolization in VAD-assisted circulation, and compare benchtop results to CFD predictions.

Computational analysis of pediatric ventricular assist device implantation to decrease cerebral particulate embolization.

Stroke is the most devastating complication after ventricular assist device (VAD) implantation with a 19% incidence and 65% mortality in the pediatric population. Current pediatric VAD technology and anticoagulation strategies alone are suboptimal. VAD implantation assisted by computational methods (CFD) may contribute reducing the risk of cerebral embolization.

Experimental study of anisotropic stress/strain relationships of the piglet great vessels and relevance to pediatric congenital heart disease.

Background: Determining material mechanical properties of neonatal aorta and pulmonary artery will aid understanding tissue behavior when subjected to abnormal hemodynamics of congenital heart disease.

Methods: Aorta and pulmonary arteries were harvested from 6 neonatal piglets (mean weight 3.5 kg).

External counterpulsation of a systemic-to-pulmonary artery shunt increases coronary blood flow in neonatal piglets.

Background: Systemic-to-pulmonary artery shunt (SPS) palliation reduces coronary blood flow (CBF), which may precipitate myocardial ischemia postoperatively.

Hypothesis: Counterpulsation (CP) of SPS augments CBF.

Methods: Seven neonatal piglets (4.

The effect of epinephrine on coronary flow in the setting of a systemic-to-pulmonary artery shunt.

Background: Indirect clinical evidence suggests that coronary blood flow (CBF) is altered in patients palliated with systemic-to-pulmonary artery shunts (SPSs). The addition of epinephrine may exert additional effects.

Methods: A total of 11 newborn piglets underwent placement of a 3.

Effects of phentolamine infusion during selective cerebral perfusion in neonatal piglets.

Background: An optimal selective cerebral perfusion protocol in pediatric cardiac surgery is unknown. Phentolamine is frequently used in pediatric cardiopulmonary bypass. We sought to determine the effects of continuous phentolamine infusion during selective cerebral perfusion.

Computational fluid dynamics in congenital heart disease.

Computational fluid dynamics has been applied to the design, refinement, and assessment of surgical procedures and medical devices. This tool calculates flow patterns and pressure changes within a virtual model of the cardiovascular system. In the field of paediatric cardiac surgery, computational fluid dynamics is being used to elucidate the optimal approach to staged reconstruction of specific defects and study the haemodynamics of the resulting anatomical configurations after reconstructive or palliative surgery.

Computational analysis of hybrid Norwood circulation with distal aortic arch obstruction and reverse Blalock-Taussig shunt.

Background: The hemodynamics characteristics of the hybrid Norwood (HN) procedure differ from those of the conventional Norwood and are not fully understood. We present a multiscale model of HN circulation to understand local hemodynamics and effects of aortic arch stenosis and a reverse Blalock-Taussig shunt (RBTS) on coronary and carotid perfusion.

Methods: Four 3-dimensional models of four HN anatomic variants were developed, with and without 90% distal preductal arch stenosis and with and without a 4-mm RBTS.

Alternative anticoagulation during cardiovascular procedures in pediatric patients with heparin-induced thrombocytopenia.

Patients with heparin-induced thrombocytopenia (HIT) that require anticoagulation for cardiovascular procedures represent a challenging and high-risk group. Bivalirudin and argatroban have been successfully used as alternative anticoagulants in adult patients with HIT. There have been few experiences published involving the pediatric population and controversy exists regarding the properties and optimal dosing of these drugs.

Shunt reduction to pulmonary arteriovenous malformations using a modified covered stent.

Pulmonary arteriovenous malformations in patients with congenital heart disease have been associated with interruption of hepatic venous return to the lungs. We report a novel technique to improve systemic saturation using a modified covered stent in a patient with unilateral left pulmonary arteriovenous malformations in the setting of a Fontan circulation.

Computational fluid dynamics analysis of surgical adjustment of left ventricular assist device implantation to minimise stroke risk.

Background: Currently, mechanical support is the most promising alternative to cardiac transplantation. Ventricular assist devices (VADs) were originally used to provide mechanical circulatory support in patients awaiting planned heart transplantation ('bridge-to-transplantation' therapy). The success of short-term bridge devices led to clinical trials evaluating the clinical suitability of long-term support ('destination' therapy) with left ventricular assist devices (LVADs).

An institutional approach to, and results for, patient with tetralogy with pulmonary atresia and major systemic-to-pulmonary collateral arteries.

Background: Tetralogy of Fallot with pulmonary atresia and diminutive or absent intrapericardial pulmonary arteries is a rare congenital abnormality, with high morbidity and mortality. Despite great advances in surgical- and catheter-based therapies, management remains challenging and controversial. We describe the surgical methods and the results from our institution.

Infantile form of scimitar syndrome with contralateral pulmonary vein stenosis.

Infantile scimitar syndrome (SS) carries significant mortality. Consistent management guidelines have not been well established, and outcomes continue to be disappointing. We present our experience managing an SS patient with complex anatomy who developed stenosis of the pulmonary veins contralateral to the hypoplastic lung.

Diagnosis and management of congenital right pulmonary venous atresia.

Congenital unilateral pulmonary venous atresia is a rare anatomical defect. Patients present with pulmonary symptoms, and diagnosis may be elusive. Pulmonary arterial wedge angiography is the gold standard with which to achieve diagnosis, and surgical intervention is often required for symptomatic patients.