Publications by authors named "William B Drake"

Brain abscess is a rare but life-threatening condition. Intracardiac or extracardiac right-to-left shunting in patients with unrepaired cyanotic congenital heart disease, pulmonary arteriovenous malformations, or venovenous collaterals allows microbes unfiltered access to the brain. Brain abscess must be considered when cyanotic patients present with headache.

View Article and Find Full Text PDF

Background: Cardiac allometric organ growth after pediatric valve replacement can lead to patient-prosthesis size mismatch and valve re-replacement, which could be mitigated with allogeneic decellularized pulmonary valves treated with collagen conditioning solutions to enhance biological and mechanical performance, termed "bioengineered valves." In this study, we evaluated functional, dimensional, and biological responses of these bioengineered valves compared with traditional cryopreserved valves implanted in lambs during rapid somatic growth.

Methods: From a consanguineous flock of 13 lambs, the pulmonary valves of 10 lambs (mean weight, 19.

View Article and Find Full Text PDF

Introduction: Patients with single ventricle physiology (SVP)--specifically, hypoplastic left heart syndrome (HLHS)--frequently need long-term enteral access; however, they are at an extremely high operative risk. Nothing has been published on the physiologic impact on single ventricle function during laparoscopy in this patient population. Therefore, we performed intraoperative transesophageal echocardiography (TEE) to study the physiologic effects of laparoscopic surgery in these patients.

View Article and Find Full Text PDF

Implantable, viable tissue engineered cardiovascular constructs are rapidly approaching clinical translation. Species typically utilized as preclinical large animal models are food stock ungulates for which cross species biological and genomic differences with humans are great. Multiple authorities have recommended developing subhuman primate models for testing regenerative surgical strategies to mitigate xenotransplant inflammation.

View Article and Find Full Text PDF

Objective: This study assesses in a baboon model the hemodynamics and human leukocyte antigen immunogenicity of chronically implanted bioengineered (decellularized with collagen conditioning treatments) human and baboon heart valve scaffolds.

Methods: Fourteen baboons underwent pulmonary valve replacement, 8 with decellularized and conditioned (bioengineered) pulmonary valves derived from allogeneic (N = 3) or xenogeneic (human) (N = 5) hearts; for comparison, 6 baboons received clinically relevant reference cryopreserved or porcine valved conduits. Panel-reactive serum antibodies (human leukocyte antigen class I and II), complement fixing antibodies (C1q binding), and C-reactive protein titers were measured serially until elective sacrifice at 10 or 26 weeks.

View Article and Find Full Text PDF

Previous studies based on fetal magnetocardiographic (fMCG) recordings used simplified volume conductor models to estimate the fetal cardiac vector as an unequivocal measure of the cardiac source strength. However, the effect of simplified volume conductor modeling on the accuracy of the fMCG inverse solution remains largely unknown. Aiming to determine the sensitivity of the source estimators to the details of the volume conductor model, we performed simulations using fetal-maternal anatomical information from ultrasound images obtained in 20 pregnant women in various stages of pregnancy.

View Article and Find Full Text PDF

Cardiopulmonary bypass (CPB) protocols of the baboon (Papio cynocephalus anubis) are limited to obtaining experimental data without concern for long-term survival. In the evaluation of pulmonary artery tissue engineered heart valves (TEHVs), pediatric CPB methods are adapted to accommodate the animals' unique physiology enabling survival up to 6 months until elective sacrifice. Aortic access was by a 14F arterial cannula and atrial access by a single 24F venous cannula.

View Article and Find Full Text PDF

Previous attempts at unequivocal specification of signal strength in fetal magnetocardiographic (fMCG) recordings have used an equivalent current dipole (ECD) to estimate the cardiac vector at the peak of the averaged QRS complex. However, even though the magnitude of fetal cardiac currents are anticipated to be relatively stable, ECD-based estimates of signal strength show substantial and unrealistic variation when comparing results from different time windows of the same recording session. The present study highlights the limitations of the ECD model, and proposes a new methodology for fetal cardiac source reconstruction.

View Article and Find Full Text PDF