Ronald K. Woods

Vascular anomalies and tracheoesophageal compression: a single institution's 25-year experience.

BACKGROUND Vascular rings are uncommon anomalies in which preferred strategies for diagnosis and treatment may vary among institutions. In this report, we offer a description of our approach and a review of our 25-year experience. METHODS A retrospective review was conducted of all pediatric patients with symptomatic tracheoesophageal compression secondary to anomalies of the aortic arch and great vessels diagnosed from 1974 to 2000. RESULTS Thirty-one patients (38%) of eighty-two patients (mean age, 1.7 years), were identified with double aortic arch, 22 patients (27%) with right arch left ligamentum, and 20 patients (24%) with innominate artery compression. Our diagnostic approach emphasized barium esophagram, along with echocardiography. This regimen was found to be reliable for all cases except those with innominate artery compression for which bronchoscopy was preferred, and except those with pulmonary artery sling for which computed tomography or magnetic resonance imaging, in addition to bronchoscopy, were preferred. Left thoracotomy was the most common operative approach (70 of 82; 85%). Ten patients (12%) had associated heart anomalies, and 6 (7%) patients underwent repair. Complications occurred in 9 (11%) patients and led to death in 3 (4%) patients. CONCLUSIONS In our practice, barium swallow and echocardiography are sufficient in diagnosing and planning the operative strategy in the majority of cases, with notable exceptions. Definitive intraoperative delineation of arch anatomy minimizes the risk of misdiagnosis or inadequate treatment.

The use of the Berlin heart EXCOR in patients with functional single ventricle

INTRODUCTION The frequency and successful use of pediatric ventricular assist devices (VADs) as a bridge to cardiac transplantation have been steadily increasing since 2003, but the experience in patients with complex congenital heart disease has not been well described. Using a large prospectively collected dataset of children supported with the Berlin Heart EXCOR VAD, we have reviewed the experience in children with single ventricular anatomy or physiology (SV), and compared the results with those supported with biventricular circulation (BV) over the same time period. METHODS The EXCOR Investigational Device Exemption study database was retrospectively reviewed. VAD implants under the primary cohort and compassionate use cohort between May 2007 and December 2011 were included in this review. RESULTS Twenty-six of 281 patients supported with a VAD were SV. The most common diagnosis was hypoplastic left heart syndrome (15 of 26). Nine patients were supported after neonatal palliative surgery (Blalock-Taussig shunt or Sano), 12 after a superior cavopulmonary connection (SCPC), and 5 after total cavopulmonary connection (TCPC). Two patients received biventricular assist devices, 1 after stage I surgery and 1 after stage II. SV patients were supported for a median time of 10.5 days (range, 1-363 days) versus 39 days (range, 0-435 days) for BV (P = .01). The ability to be bridged to transplant or recovery in SV patients is lower than for BV patients (11 of 26 [42.3%] vs 185 of 255 [72.5%]; P = .001). Three of 5 patients with TCPC were successfully bridged to transplant and were supported with 1 VAD. Seven of 12 patients with SCPC were bridged to transplant, and only 1 of 9 patients supported after a stage I procedure survived. CONCLUSIONS The EXCOR Pediatric VAD can provide a bridge to transplant for children with SV anatomy or physiology, albeit less successfully than in children with BV. In this small series, results are better in patients with SCPC and TCPC. VAD support for patients with shunted sources of pulmonary blood flow should be applied with caution.

Use of a HeartWare Ventricular Assist Device in a Patient With Failed Fontan Circulation

We present a successful case of the use of a HeartWare ventricular assist device as a bridge to transplantation in an 11-year-old with a hypoplastic left heart and failed Fontan circulation.

Mechanical Support as Failure Intervention in Patients with Cavopulmonary Shunts (MFICS): Rationale and Aims of a New Registry of Mechanical Circulatory Support in Single Ventricle Patients

It is now recognized that a majority of single ventricle patients, those with functionally univentricular hearts, who have survived palliative cavopulmonary connection will experience circulatory failure and end-organ dysfunction due to intrinsic inadequacies of a circulation supported by a single ventricle. Thus, there are an increasing number of patients with functional single ventricles presenting with failing circulations that may benefit from mechanical circulatory support (MCS). The paucity of experience with MCS in this population, even at high volume cardiac centers, contributes to limited available data to guide MCS device selection and management. Thus, a registry of MCS in this population would be beneficial to the field. A conference was convened in January 2012 of pediatric and adult cardiologists, pediatric cardiac intensivists, congenital heart surgeons, and adult cardiothoracic surgeons to discuss the current state of MCS, ventricular assist device, and total artificial heart therapy for patients who have undergone cavopulmonary connection, either superior cavopulmonary connection or total cavopulmonary connection. Specifically, individual experience and challenges with VAD therapy in this population was reviewed and creation of a multiinstitutional registry of MCS/ventricular assist device in this population was proposed. This document reflects the consensus from the meeting and provides a descriptive overview of the registry referred to as Mechanical Support as Failure Intervention in Patients with Cavopulmonary Shunts.

Three-dimensional electron spin resonance imaging

Abstract Three-dimensional electron spin resonance images have been obtained by reconstruction from projections, permitting unambiguous determinations of the distribution of unpaired electrons in several complex objects. Examples of applications to several objects are presented.

Outcomes of systemic to pulmonary artery shunts in patients weighing less than 3 kg: analysis of shunt type, size, and surgical approach.

OBJECTIVE To evaluate outcomes of systemic to pulmonary artery shunts (SPS) in patients weighing less than 3 kg with regard to shunt type, shunt size, and surgical approach. METHODS Patients weighing less than 3 kg who underwent modified Blalock-Taussig or central shunts with polytetrafluoroethylene grafts at our institution from January 1, 2000, to May 31, 2011, were reviewed. Patients who had undergone other major concomitant procedures were excluded from the analysis. Primary outcomes included mortality (discharge mortality and mortality before next planned palliative procedure or definitive repair), cardiac arrest and/or extracorporeal membrane oxygenation (ECMO), and shunt reintervention. RESULTS In this cohort of 80 patients, discharge survival was 96% (77/80). Postoperative cardiac arrest or ECMO occurred in 6/80 (7.5%), and shunt reintervention was required in 14/80 (17%). On univariate analysis, shunt reintervention was more common in patients with 3-mm shunts (11/30, 37%) compared with 3.5-mm (2/36, 6%) or 4-mm shunts (1/14, 7%) (P < .003). There were no statistically significant associations between shunt type, shunt size, or surgical approach and cardiac arrest/ECMO or mortality. Multiple logistic regression demonstrated that a shunt size of 3 mm (P = .019) and extracardiac anomaly (P = .047) were associated with shunt reintervention, whereas no variable was associated with cardiac arrest/ECMO or mortality. CONCLUSIONS In this high-risk group of neonates weighing less than 3 kg at the time of SPS, survival to discharge and the next planned surgical procedure was high. Outcomes were good with the 3.5- and 4-mm shunts; however, shunt reintervention was common with 3-mm shunts.

Spectral-spatial ESR imaging as a method of noninvasive biological oximetry

Abstract Using a spectral range of 3.5 G, spectral-spatial ESR imaging has been applied to obtain noninvasively a quantitative spatial description of intracellular oxygen concentrations in vitro . The results of simulations and experiments with phantoms are presented to demonstrate the validity of this technique.

Recovery of vocal fold immobility following isolated patent ductus arteriosus ligation

OBJECTIVE Identify laryngoscopic and functional outcomes of infants with vocal fold immobility (VFI) following patent ductus arteriosus (PDA) ligation and identify predictors of recovery. METHODS Retrospective review of patients with VFI following PDA ligation from 2001 to 2012 at a single institution. Inclusion criteria were: (1) PDA ligation as only cardiac surgical procedure; (2) left VFI documented by laryngoscopy; (3) minimum follow up 120 days, with at least 2 laryngoscopies performed. Resolution of VFI was determined at follow-up laryngoscopy. Univariate logistic regression models were used to identify variables associated with VFI recovery. RESULTS 66 subjects were included with median follow up of 3.0 (± 2.1) years. The mean gestational age was 24.5 ± 1.4 weeks, mean birth weight 673 ± 167 g, and mean age at procedure was 18.6 ± 14.3 days. Patients presented with respiratory symptoms (39%), dysphonia (78%) and dysphagia (55%). Resolution of VFI was observed in 2/66 (3%) patients. Recovery was documented at 20 days and 11 months respectively. Respiratory symptoms, dysphagia, and dysphonia persisted at last follow up in 11%, 47%, and 20% of patients. CONCLUSIONS VFI associated with ligation of the ductus arteriosus has a low rate of recovery. Clinical symptoms frequently persist, and as such regular follow-up by otolaryngologists to mitigate morbidity is indicated.

Electron spin resonance microscopy of an in vitro tumour model.

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Bilateral Pulmonary Artery Banding as Rescue Intervention in High-Risk Neonates

BACKGROUND Presentation in shock and preoperative infection remain risk factors for neonatal cardiac surgery. This report describes bilateral pulmonary artery banding (bPAB) in ductal-dependent lesions with systemic outflow obstruction as rescue intervention before surgery with cardiopulmonary bypass in these high-risk neonates. METHODS A retrospective chart review was conducted for 10 patients who underwent bPAB before conventional surgery with cardiopulmonary bypass. Patient characteristics including birth weight, gestational age, cardiac and noncardiac diagnoses, preoperative and postoperative markers of organ function, and outcome measures were examined. RESULTS The majority of patients (8 of 10) were considered high-risk owing to multiorgan dysfunction syndrome. The median age at bPAB was 12 days (range, 5 to 26 days), and the median interval between bPAB and second surgery was 10.5 days (range, 5 to 79 days). Organ function improved after admission and continued to improve after bPAB in 9 of 10 patients. No patient experienced new complications between bPAB and subsequent operation. Of 8 patients who had stage I palliation, 5 have undergone or are awaiting completion Fontan, 1 underwent Kawashima procedure, 1 underwent orthotopic heart transplant, and 1 with hypoplastic left heart syndrome and intact atrial septum died at 44 days old. Both patients who underwent biventricular repair are alive and well. Median follow-up for survivors was 2.9 years (range, 0.25 to 6.25 years). CONCLUSIONS Bilateral pulmonary artery banding is safe in ductal-dependent lesions with systemic outflow obstruction. High-risk patients with preoperative organ dysfunction or infection can recover within a short period and become lower risk candidates for complex congenital heart surgery using cardiopulmonary bypass.