Victor O. Morell

Short- and intermediate-term survival after extracorporeal membrane oxygenation in children with cardiac disease

OBJECTIVES In children with cardiac disease, common indications for extracorporeal membrane oxygenation (ECMO) include refractory cardiopulmonary resuscitation (E-CPR), failure to separate from cardiopulmonary bypass (OR-ECMO), and low cardiac output syndrome (LCOS-ECMO). Despite established acceptance, ECMO outcomes are suboptimal with a survival between 38% and 55%. We evaluated factors associated with significantly increased survival in cardiac patients requiring ECMO. METHODS We conducted a retrospective investigation of consecutive patients undergoing ECMO between 2006 and 2010. Demographic, pre-ECMO, ECMO, and post-ECMO parameters were analyzed. Neurologic outcomes were assessed with the pediatric overall performance category scale at the latest follow-up. RESULTS There were 3524 admissions, 95 (3%) of which necessitated ECMO; 40 (42%) E-CPR, 31 (33%) OR-ECMO, and 24 (25%) LCOS-ECMO. The overall hospital survival was 73%. The within-groups hospital survival was 75% in E-CPR, 77% OR-ECMO and 62% LCOS-ECMO. In the multivariable logistic regression analysis, chromosomal anomalies (odds ratio [OR], 8; 95% confidence interval [CI], 2-35), single ventricle (OR ,6; 95% CI, 3-33), multiple ECMO runs (OR, 15; 95% CI, 4-42), higher 24-hour ECMO flows (OR, 8; 95% CI, 4-22), decreased lung compliance (OR, 5; 95% CI, 2-16), and need for plasma exchange (OR, 5; 95% CI, 3-18) were all significant factors associated with mortality. From the univariate analysis, a common parameter associated with mortality within all groups was intracranial hemorrhage. At 1.9 years (0.9, 2.9) of follow-up, 66% were still alive, and 89% of survivors had normal function or only mild neurodevelopmental disability. CONCLUSIONS ECMO was successfully used in children with cardiac disease with 73% and 66% short- and intermediate-term survival, respectively. The majority of the survivors had normal function or only a minimal neurodevelopmental deficit.

Right Ventricular Outflow Tract Reconstruction With Bicuspid Valved Polytetrafluoroethylene Conduit

BACKGROUND In general, all conduits available for right ventricular outflow tract (RVOT) reconstruction eventually become stenotic or insufficient. Owing to the lack of an ideal conduit and with the hope of reducing the incidence of reoperations, we have developed and utilized a bicuspid valved polytetrafluoroethylene (PTFE) conduit for the reconstruction of the RVOT. The purpose of this study was to review our early experience with this conduit. METHODS From October 2008 to September 2009, we have implanted bicuspid valved PTFE conduits in 18 patients with a median age of 1.7 years (range 6 days to 16 years). Their diagnoses include tetralogy of Fallot with pulmonary atresia in 8, truncus arteriosus in 6, congenital aortic stenosis in 2, transposition of great arteries in 1, and interrupted aortic arch with a ventricular septal defect in 1. In 16 patients, a complete biventricular repair was performed. In another 2 cases, the conduit was used for palliative RVOT reconstruction. The conduit sizes varied from 10 mm to 24 mm in diameter. Three-dimensional flow fields obtained from computational fluid dynamics studies were utilized in the conduit design process. RESULTS There was no surgical mortality or reinterventions associated with the PTFE conduit placement in our series. At the time of discharge, none of the patients had any echocardiographic findings consistent with significant conduit stenosis or insufficiency. During the follow-up period of 6.2 ± 3.9 months, all patients were alive and only 3 had more than mild pulmonary insufficiency. CONCLUSIONS Our bicuspid valved PTFE conduit has an acceptable early performance, with a low incidence of valve insufficiency and no conduit stenosis. Certainly, longer follow-up is necessary to fully assess its long-term benefits.

Neurodevelopmental Outcomes after Pediatric Cardiac ECMO Support

Purpose: To characterize the neurodevelopmental outcomes and identify factors associated with poor outcomes in pediatric patients undergoing cardiac extracorporeal membrane oxygenation (ECMO). Methods: Five year retrospective review, including demographics, cardiac lesion, and surgical complexity, reason for ECMO, ECMO complications, and neurodevelopmental status at discharge and latest follow-up. Neurodevelopmental status was determined through the Pediatric Overall Performance Category and Pediatric Cerebral Performance Category Scales. Results: Overall ECMO survival was 73% at hospital discharge and 66% a t the latest follow-up. Most patients underwent cardiopulmonary resuscitation (CPR) (43%), and the majority (53%) had a significant disease complexity (Aristotle = 4). Complications occurred in 42% of the ECMO runs, of which 12% were intracranial injuries. At hospital discharge, 75% of patients had normal to mild disability, improving to 81% at 2 years follow-up. At hospital discharge, moderate to severe disability was associated with CPR, plasma exchange or intracranial insults. After discharge, 23% showed improvement in neurologic status and 4% showed deterioration. Cerebral infarction was the only parameter associated with deterioration at the later follow-up stage. Conclusion: Extracorporeal membrane oxygenation was successfully used in children with cardiac disease with 73 and 66% short and long-term survival respectively. Majority of the survivors had normal to mild neurodevelopmental disability and a significant portion showed neurologic improvement by the latest follow-up. Nevertheless, despite the grossly favorable outcomes standardized comprehensive neuropsychological testing is of paramount importance in all these patients.

In Vitro Evaluation of Right Ventricular Outflow Tract Reconstruction With Bicuspid Valved Polytetrafluoroethylene Conduit

Conduits available for right ventricular outflow tract (RVOT) reconstruction eventually become stenotic and/or insufficient due to calcification. In order to reduce the incidence of reoperations we have developed and used a bicuspid valved polytetrafluoroethylene (PTFE) conduit for the RVOT reconstruction. The purpose of this study is to investigate the hemodynamic performance of the new design using a pediatric in vitro right heart mock loop. PTFE conduit has been used for the complete biventricular repair of 20 patients (age 1.7±6 years) with cyanotic congenital defects. To account for the large variability of conduit sizes, 14, 16, 22, and 24-mm conduit sizes were evaluated using an in vitro flow loop comprised of a pulsatile pump with cardiac output (CO) of 1.2-3.2L/min, bicuspid valved RVOT conduit, pulmonary artery, venous compartments, and the flow visualization setup. We recorded the diastolic valve leakage and pre- and post-conduit pressures in static and pulsatile settings. In vitro valve function and overall hemodynamic performance was evaluated using high-speed cameras and ultrasonic flow probes. Three-dimensional flow fields for different in vivo conduit curvatures and inflow regimes were calculated by computational fluid dynamics (CFD) analysis to further aid the conduit design process. The average pressure drop over the valved conduits was 0.8±1.7mm Hg for the CO range tested. Typical values for regurgitant fraction, peak-to-peak pressure gradient, and effective office area were 23±2.1%, 13±2.4mm Hg, and 1.56±0.2 cm(2) , respectively. High-speed videos captured the intact valve motion with asymmetrical valve opening during the systole. CFD simulations demonstrated the flow skewness toward the major curvature of the conduit based on the pulmonic curvature. In vitro evaluation of the bicuspid valved PTFE conduit coincides well with acceptable early clinical performance (mild insufficiency), with relatively low pressure drop, and intact valve motion independent from the conduit curvature, orientation or valve location, but at the expense of increased diastolic flow regurgitation. These findings benchmark the baseline performance of the bicuspid valved conduit and will be used for future designs to improve valve competency.

The role of Fontan's procedure and aortic translocation in the surgical management of patients with discordant atrioventricular connections, interventricular communication, and pulmonary stenosis or atresia

A variety of surgical strategies have been utilized in attempts to accomplish long-term haemodynamic stability in patients with cardiac anomalies characterized by discordant atrioventricular connections, ventricular septal defect, and severe sub-pulmonary obstruction. The majority of these patients have what is commonly referred to as congenitally corrected transposition, together with a ventricular septal defect and pulmonary stenosis or atresia, in the setting of either usual or mirror imaged arrangement of the atrial chambers and the other organs of the body. A smaller sub-group, with discordant atrioventricular connections and double outlet right ventricle, with severe sub-pulmonary obstruction or pulmonary atresia, present similar physiology, and a comparable surgical challenge.

Safety and Efficacy of Implementing a Multidisciplinary Heart Team Approach for Revascularization in Patients With Complex Coronary Artery Disease: An Observational Cohort Pilot Study

IMPORTANCE Since the advent of transcatheter aortic valve replacement, the multidisciplinary heart team (MHT) approach has rapidly become the standard of care for patients undergoing the procedure. However, little is known about the potential effect of MHT on patients with coronary artery disease (CAD). OBJECTIVE To determine the safety and efficacy of implementing the MHT approach for patients with complex CAD. DESIGN, SETTING, AND PARTICIPANTS Observational cohort pilot study of 180 patients with CAD involving more than 1 vessel in a single major academic tertiary/quaternary medical center. From May 1, 2012, through May 31, 2013, MHT meetings were convened to discuss evidence-based management of CAD. All cases were reviewed by a team of interventional cardiologists and cardiac surgeons within 72 hours of angiography. All clinical data were reviewed by the team to adjudicate optimal treatment strategies. Final recommendations were based on a consensus decision. Outcome measures were tracked for all patients to determine the safety and efficacy profile of this pilot program. EXPOSURES Multidisciplinary heart team meeting. MAIN OUTCOMES AND MEASURES Thirty-day periprocedural mortality and rate of major adverse cardiac events. RESULTS Most of the patients underwent percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG); a small percentage of patients underwent a hybrid procedure or medical management. Incidence of 30-day periprocedural mortality was low across all groups of patients (PCI group, 5 of 64 [8%]; CABG group, 1 of 87 [1%]). The rate of major adverse cardiac events during a median follow-up of 12.1 months ranged from 12 of 87 patients (14%) in the CABG group to 15 of 64 (23%) in the PCI group. CONCLUSIONS AND RELEVANCE Outcomes of patients with complex CAD undergoing the optimal treatment strategy recommended by the MHT were similar to those of published national standards. Implementation of the MHT approach for patients with complex CAD is safe and efficacious.

Total cavopulmonary connection in patients with apicocaval juxtaposition: optimal conduit route using preoperative angiogram and flow simulation †

OBJECTIVES Single ventricle with apicocaval juxtaposition (ACJ) is a rare, complex anomaly, in which the optimal position of the conduit for completion of total cavopulmonary connection (TCPC) is still controversial. The purpose of this study was to identify a preoperative method for optimal conduit position using the IVC anatomy and computational fluid dynamics (CFD). METHODS Twenty-four patients with ACJ (5.3 ± 5.7 years) who underwent TCPC were enrolled. A conduit was placed ipsilateral to the cardiac apex in each of 11 patients, of which 9 were intra-atrial and 2 extracardiac (group A) and, in a further 13 patients, extracardiac on the contralateral side (group B). As control, 10 patients with tricuspid atresia were also enrolled (group C). The location of the IVC in relation to the spine was evaluated from the frontal view of preoperative angiogram, using the following index: IVC-index = IVC width overlapping the vertebra/width of the vertebra × 100%. Energy loss was calculated by CFD simulation. RESULTS IVC-index of group B was larger than groups A and C (45 ± 26 vs. 20 ± 21 and 28 ± 19%, P = 0.03). Postoperative catheterizations showed that, due to its curvature, conduit length in group B was significantly longer than the others (65 ± 12 vs. 36 ± 14 and 44 ± 10 mm, P < 0.001), although there was no statistical difference in central venous pressure or cardiac output. CFD studies revealed less energy loss in group A conduits compared with group B (1.6 ± 0.3 vs. 3.6 ± 0.6 mW, P = 0.05), although this did not appear to be clinically significant. Moreover, CFD simulation showed significant energy loss within the Fontan circulation when the conduit was either compressed or kinked: 4.9 and 18.2 mW respectively. CONCLUSIONS In patients with ACJ, placement of a straighter and shorter conduit on the ventricular apical side provides better laminar blood flow with less energy loss. However, conduit compression and kinking are far more detrimental to the Fontan circulation. A preoperative IVC-index is pivotal for avoiding these factors and deciding the optimal conduit route.

Brain Dysplasia Associated with Ciliary Dysfunction in Infants with Congenital Heart Disease

OBJECTIVE To test for associations between abnormal respiratory ciliary motion (CM) and brain abnormalities in infants with congenital heart disease (CHD) STUDY DESIGN: We recruited 35 infants with CHD preoperatively and performed nasal tissue biopsy to assess respiratory CM by videomicroscopy. Cranial ultrasound scan and brain magnetic resonance imaging were obtained pre- and/or postoperatively and systematically reviewed for brain abnormalities. Segmentation was used to quantitate cerebrospinal fluid and regional brain volumes. Perinatal and perioperative clinical variables were collected. RESULTS A total of 10 (28.5%) patients with CHD had abnormal CM. Abnormal CM was not associated with brain injury but was correlated with increased extraaxial cerebrospinal fluid volume (P < .001), delayed brain maturation (P < .05), and a spectrum of subtle dysplasia including the hippocampus (P < .0078) and olfactory bulb (P < .034). Abnormal CM was associated with higher composite dysplasia score (P < .001), and both were correlated with elevated preoperative serum lactate (P < .001). CONCLUSIONS Abnormal respiratory CM in infants with CHD is associated with a spectrum of brain dysplasia. These findings suggest that ciliary defects may play a role in brain dysplasia in patients with CHD and have the potential to prognosticate neurodevelopmental risks.

Formation of Ventricular Aneurysm After Endocarditis in a Child With Methicillin-Resistant Staphylococcus aureus (MRSA) Bacteremia

A 3-year-old previously healthy girl was admitted with fever, leg pain, and refusal to ambulate after minor leg trauma. Her blood culture results at admission were positive for methicillin-resistant Staphylococcus aureus (MRSA), and her inflammatory markers were elevated: erythrocyte sedimentation rate (ESR), 59; C-reactive protein (CRP), 25. Broad-spectrum intravenous antibiotic coverage was initiated. Contrast-enhanced magnetic resonance imaging (MRI) showed extensive osteomyelitis of both lower extremities, bilateral hip septic arthritis, and multiple chest wall abscesses. On hospital day 9, a transthoracic echocardiogram exhibited vegetations near the tricuspid and mitral valves and coronary sinus (Fig. 1). On day 9, the first negative blood culture was obtained, and a follow-up echocardiogram on day 12 showed resolution of vegetations with concurrent improvement of inflammatory markers (ESR, 17). On day 22, the girl experienced high fever and elevated ESR (125), with continuing negative blood cultures. A follow-up echocardiogram showed a 1.3 9 2.3-cm posterior septal pseudoaneurysm in communication with the left ventricle (Fig. 2). To define the anatomic location of the aneurysm further, a contrast-enhanced cardiac MRI was performed, which showed a pear-shaped aneurysm at the posterior crux of the heart measuring 5.8 cm in length, 1.8 cm in width and 1.8 cm anteroposteriorly (Fig. 3). The operative findings during surgical repair on day 28 showed a contained left ventricular rupture just distal to the mitral valve annulus with fibropurulent material at the abscess site. The girl underwent surgical repair with placement of a ventricular septal patch. Postoperative echocardiograms showed no residual aneurysm. She was discharged home with resolution of her symptoms and improvement in her inflammatory markers (ESR, 21). A follow-up echocardiogram 21 months later was unchanged, and at this writing, the girl continues to be asymptomatic. Despite negative blood culture results and continued broad-spectrum antibiotics, our patient had progression of her cardiac findings with development of myocardial abscess. Her inflammatory markers closely corresponded to the disease course. Myocardial abscesses are uncommonly reported among children with a structurally normal heart and no prior evidence of congenital heart disease [2]. However, this lifethreatening complication of endocarditis requires early diagnosis and surgical repair [1]. One recent report showed pancarditis and formation of a ventricular septal abscess associated with staph bacteremia that had good surgical repair in a pediatric patient [3]. According to our L. Gaur (&) Pediatric Cardiology, Children’s National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA e-mail: lgaur@cnmc.org

Perioperative mortality is the Achilles heel for cardiac transplantation in adults with congenital heart disease: Evidence from analysis of the UNOS registry.

Adults with congenital heart disease may present with end‐stage heart failure necessitating orthotopic heart transplant (OHT). We sought to review the United Network for Organ Sharing (UNOS) experience with this unique cohort focusing on surgical outcomes and survival.