David L.S. Morales

Hypoplastic Left Heart Syndrome : Current Considerations and Expectations

In the recent era, no congenital heart defect has undergone a more dramatic change in diagnostic approach, management, and outcomes than hypoplastic left heart syndrome (HLHS). During this time, survival to the age of 5 years (including Fontan) has ranged from 50% to 69%, but current expectations are that 70% of newborns born today with HLHS may reach adulthood. Although the 3-stage treatment approach to HLHS is now well founded, there is significant variation among centers. In this white paper, we present the current state of the art in our understanding and treatment of HLHS during the stages of care: 1) pre-Stage I: fetal and neonatal assessment and management; 2) Stage I: perioperative care, interstage monitoring, and management strategies; 3) Stage II: surgeries; 4) Stage III: Fontan surgery; and 5) long-term follow-up. Issues surrounding the genetics of HLHS, developmental outcomes, and quality of life are addressed in addition to the many other considerations for caring for this group of complex patients.

Berlin Heart EXCOR Pediatric Ventricular Assist Device for Bridge to Heart Transplantation in US Children

Background— Recent data suggest that the Berlin Heart EXCOR Pediatric ventricular assist device is superior to extracorporeal membrane oxygenation for bridge to heart transplantation. Published data are limited to 1 in 4 children who received the device as part of the US clinical trial. We analyzed outcomes for all US children who received the EXCOR to characterize device outcomes in an unselected cohort and to identify risk factors for mortality to facilitate patient selection. Methods and Results— This multicenter, prospective cohort study involved all children implanted with the Berlin Heart EXCOR Pediatric ventricular assist device at 47 centers from May 2007 through December 2010. Multiphase nonproportional hazards modeling was used to identify risk factors for early (<2 months) and late mortality. Of 204 children supported with the EXCOR, the median duration of support was 40 days (range, 1–435 days). Survival at 12 months was 75%, including 64% who reached transplantation, 6% who recovered, and 5% who were alive on the device. Multivariable analysis identified lower weight, biventricular assist device support, and elevated bilirubin as risk factors for early mortality and bilirubin extremes and renal dysfunction as risk factors for late mortality. Neurological dysfunction occurred in 29% and was the leading cause of death. Conclusions— Use of the Berlin Heart EXCOR has risen dramatically over the past decade. The EXCOR has emerged as a new treatment standard in the United States for pediatric bridge to transplantation. Three-quarters of children survived to transplantation or recovery; an important fraction experienced neurological dysfunction. Smaller patient size, renal dysfunction, hepatic dysfunction, and biventricular assist device use were associated with mortality, whereas extracorporeal membrane oxygenation before implantation and congenital heart disease were not.

Bridging children of all sizes to cardiac transplantation: The initial multicenter North American experience with the Berlin Heart EXCOR ventricular assist device

BACKGROUND Beginning in 2000 and accelerating in 2004, the Berlin Heart EXCOR (Berlin Heart Inc Woodlands, TX) became the first pediatric-specific ventricular assist device (VAD) applied throughout North America for children of all sizes. This retrospective study analyzed the initial Berlin Heart EXCOR pediatric experience as a bridge to transplantation. METHODS Between June 2000 and May 2007, 97 EXCOR VADs were implanted in North America at 29 different institutions. The analysis is limited to 73 patients (75%) from 17 institutions, for which retrospective data were available. RESULTS Median age and weight at VAD implant were 2.1 years (range, 12 days-17.8 years) and 11 kg (range, 3-87.6 kg), respectively. The primary diagnoses were dilated cardiomyopathy in 42 (58%), congenital heart disease in 19 (26%), myocarditis in 7 (10%), and other cardiomyopathies in 5 (7%). Pre-implant clinical condition was critical cardiogenic shock in 38 (52%), progressive decline in 33 (45%), or other in 2 (3%). Extracorporeal membrane oxygenation was used as a bridge to EXCOR in 22 patients (30%). Device selection was left VAD (LVAD) in 42 (57%) and biventricular assist devices (BiVAD) in 31 (43%). The EXCOR bridged 51 patients (70%) to transplant and 5 (7%) to recovery. Mortality on the EXCOR was 23% (n = 17) overall, including 35% (11 of 31) in BiVAD vs 14% (6 of 42) in LVAD patients (p = 0.003). Multivariate analysis showed younger age and BiVAD support were significant risk factors for death while on the EXCOR. CONCLUSIONS This limited but large preliminary North American experience with the Berlin Heart EXCOR VAD as a bridge to cardiac transplantation for children of all ages and sizes points to the feasibility of this approach. The prospective investigational device evaluation trial presently underway will further characterize the safety and efficacy of the EXCOR as a bridge to pediatric cardiac transplantation.

Successful linking of the Society of Thoracic Surgeons adult cardiac surgery database to Centers for Medicare and Medicaid Services Medicare data.

BACKGROUND The Centers for Medicare and Medicaid Services (CMS) Medicare database complements The Society of Thoracic Surgeons (STS) database by providing information about long-term outcomes and cost. This study demonstrates the feasibility of linking STS data to CMS data and examines the penetration, completeness, and representativeness of the STS database. METHODS Using variables common to both STS and CMS databases, STS operations were linked to CMS data for all CMS coronary artery bypass graft surgery (CABG) hospitalizations discharged between 2000 and 2007, inclusive. For each CMS CABG hospitalization, it was determined whether a matching STS record existed. RESULTS Center-level penetration (number of CMS sites with at least one matched STS participant divided by the total number of CMS CABG sites) increased from 45% to 78%. In 2007, 854 of 1,101 CMS CABG sites (78%) were linked to an STS site. Patient-level penetration (number of CMS CABG hospitalizations done at STS sites divided by the total number of CMS CABG hospitalizations) increased from 51% to 84%. In 2007, 94,409 of 111,967 CMS CABG hospitalizations (84%) were at an STS site. Completeness of case inclusion at STS sites (number of CMS CABG cases at STS sites linked to STS records divided by the total number of CMS CABG cases at STS sites) increased from 88% to 97%. In 2007, 88,857 of 91,363 CMS CABG hospitalizations at STS sites (97%) were linked to an STS record. CONCLUSIONS The successful linking of STS and CMS databases demonstrates high and increasing penetration and completeness of the STS database. Linking STS and CMS data will facilitate studying long-term outcomes of cardiothoracic surgery.

Outcomes of pediatric patients supported by the HeartMate II left ventricular assist device in the United States

OBJECTIVE The HeartMate II (HMII; Thoratec, Pleasanton, CA) continuous-flow left ventricular assist device (LVAD) is an established treatment modality for advanced heart failure in adults. The objective of this study was to evaluate outcomes of pediatric patients supported by the HMII LVAD. METHODS This was a retrospective review of the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) of patients supported with a HMII from April 2008 to September 2011. The primary cohort comprised pediatric patients aged 11 to 18 years. Outcomes were compared with a group of young adults aged 19 to 39 years who underwent HMII implant during the same period. Ischemic etiologies for heart failure were excluded. RESULTS There were 28 pediatric patients, of whom 19 (68%) were males, 14 (46%) were African American, and 7 (25%) underwent device placement in a pediatric hospital. Competing outcomes analysis showed that at 6 months of follow-up, the composite of survival to transplantation, ongoing support, or recovery was 96% for the pediatric group, which was not significantly different from the young adult group (96%, p = 0.330). The 2 groups had similar INTERMACS profiles but differed in diagnosis, weight, and morbidities. Bleeding complications requiring surgical intervention were more common in the pediatric group. CONCLUSIONS Pediatric outcomes with a HMII LVAD are comparable to that of young adults. As we continue to monitor this growing group, more sophisticated characterization and comparisons will be possible. Also, as technology progress and second- and third-generation devices are introduced, the number of children who will benefit from mechanical support will continue to grow.

The International Society for Heart and Lung Transplantation Guidelines for the management of pediatric heart failure: Executive summary

From the Freeman Hospital, Newcastle upon Tyne, United Kingdom; Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada; Stanford University, Stanford, California; Columbia University Medical Center, New York, New York; Great Ormond Street Hospital, London, United Kingdom; Joe DiMaggio Children’s Hospital, Hollywood, Florida; Primary Children’s Medical Center, Salt Lake City, Utah; C.S. Mott Children’s Hospital, Ann Arbor, Michigan; Children’s Hospital, Denver, Colorado; Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio; Ann & Robert H Lurie Children’s Hospital, Chicago, Illinois; Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania; and the Royal Melbourne Children’s Hospital, Melbourne, Victoria, Australia.

Pediatric heart transplant waiting list mortality in the era of ventricular assist devices

BACKGROUND Earlier reviews have reported unacceptably high incidence of pediatric heart transplant (PHT) waiting list mortality. An increase in ventricular assist devices (VAD) suggests a potential positive effect. This study evaluated PHT waiting list mortality in the era of pediatric VADs. METHODS United Network of Organ Sharing (UNOS) database from 1999 to 2012 showed 5,532 pediatric candidates (aged ≤ 18 years) actively listed for PHT: 2,191 were listed in 1999 to 2004 (Era 1) and 3,341 were listed in 2005 to 2012 (Era 2). RESULTS Waiting list mortality was lower in Era 2 (8%) vs Era 1 (16%; p < 0.001). VAD therapy was used more frequently in Era 2 (16%) than in Era 1 (6%; p < 0.001) and was associated with better waiting list survival (p < 0.001). There were more UNOS Status 1A patients in Era 2 (80%) vs Era 1 (68%; p < 0.001). Independent predictors of waiting list mortality included weight < 10 kg (odds ratio [OR], 2.7 95% confidence interval [CI], 1.1-6.9), congenital heart disease diagnosis (OR, 2.4; 95% CI, 1.9-3.0), blood type O (OR, 2.2; 95% CI, 1.8-2.8)], extracorporeal membrane oxygenation (OR, 1.5; 95% CI, 1.1-2.2), mechanical ventilation (OR, 1.8; 95% CI, 1.4-2.3), and renal dysfunction (OR 1.6; 95% CI, 1.2-2.0). Independent predictors of survival on the waiting list included VAD therapy (OR 4.2; 95% CI, 2.4-7.6), cardiomyopathy diagnosis (OR 3.3; 95% CI, 2.4-4.6), blood type A (OR, 2.2; 95% CI, 1.8-2.8), UNOS list Status 1B (OR, 1.9; 95% CI, 1.2-3.0), listed in Era 2 (OR 1.8; 95% CI, 1.4-2.2), and white race (OR 1.3; 95% CI, 1.1-1.6). CONCLUSIONS Despite an increase in the number of children listed as Status 1A, there was more than a 50% reduction in waiting list mortality in the new era. Irrespective of other factors, patients supported with a VAD were 4 times more likely to survive to transplant.

Quality Measures for Congenital and Pediatric Cardiac Surgery

This article presents 21 “Quality Measures for Congenital and Pediatric Cardiac Surgery” that were developed and approved by the Society of Thoracic Surgeons (STS) and endorsed by the Congenital Heart Surgeons’ Society (CHSS). These Quality Measures are organized according to Donabedian’s Triad of Structure, Process, and Outcome. It is hoped that these quality measures can aid in congenital and pediatric cardiac surgical quality assessment and quality improvement initiatives.

Current Expectations for Surgical Repair of Isolated Ventricular Septal Defects

BACKGROUND Ventricular septal defect (VSD) is the most commonly recognized congenital heart defect. With the development of device closure for intracardiac defects, we sought to evaluate current expectations for surgical closure of isolated VSD. METHODS Between January 1, 2000, and December 31, 2006, 215 patients underwent isolated VSD repair at a median age of 10 months (range, 20 days to 18 years) and a median weight of 7 kg (range, 2 to 66 kg). The following VSD types were found: 172 perimembranous (80%), 28 supracristal (13%), 6 inlet (3%), and 9 muscular (4%). One hundred eight patients (50%) had evidence of congestive heart failure or failure to thrive preoperatively. Thirty-one patients (14%) had aortic valve cusp prolapse, and 63 (29%) had genetic abnormalities. RESULTS Incidence of significant postoperative complications was extremely low. No patient underwent reoperation for a residual VSD. None had complete heart block. One operative mortality (0.5%) and 2 late deaths (0.9%) occurred. Median postoperative hospital length of stay was 5 days (range, 2 to 187 days). In the immediate postoperative period, 6 patients (2.8%) required reoperation. No patients were discharged on antiarrhythmic agents, had complete heart block, or required permanent pacing. At mean follow-up of 2.1 +/- 2.0 years, 99.5% (211 of 212) of patients were asymptomatic from a cardiac standpoint. None exhibited greater than mild new-onset tricuspid valve regurgitation. No aortic valve injuries occurred. CONCLUSIONS Surgical closure of isolated VSD is a safe, effective therapy. Risk of death, complete heart block, and reoperation is minimal. As new technologies for VSD closure evolve, results such as these should be considered when evaluating patients, choosing therapeutic options, and counseling families.

Extubation in the Operating Room After Fontan's Procedure: Effect on Practice and Outcomes

BACKGROUND Timely extubation is a well-accepted strategy in the postoperative intensive care unit management of Fontan patients to minimize the deleterious effects of positive-pressure ventilation. In October 2002, this strategy was extended to extubating selective Fontan patients in the operating room (EOR). This retrospective study examines how EOR has affected outcomes and practice in our Fontan population. METHODS Between October 2002 and June 2006, 112 patients underwent primary Fontan procedures; 38 (34%) were EOR and 74 (66%) were non-EOR. These two cohorts were not different (p < 0.05) in age, weight, surgery time, dominant ventricular morphology, hypoplastic left heart syndrome, prior bidirectional Glenn, concomitant procedures, atrioventricular valve regurgitation, and ventricular function. Analysis of variance was used to compare mean pulmonary artery pressure, mean arterial blood pressure, and mean common atrial pressure as a function of time. RESULTS During the first 12 hours postoperatively, mean pulmonary artery pressure and mean common atrial pressure were significantly lower and mean arterial blood pressure was significantly higher in the EOR group than the non-EOR group (p < 0.05). No EOR patient required reintubation. Mean durations of inotropic agents (1.1 versus 2.4 days), chest tubes (5.8 versus 7.2 days), intensive care unit stay (3 versus 4.7 days), and hospital stay (8.6 versus 11.3 days) for EOR patients were shorter than for non-EOR patients (p < 0.05). Intensive care unit and hospital costs for EOR patients were 35% and 31% lower, respectively, than for non-EOR patients (p < 0.05). Kaplan-Meier survival for EOR patients (3 years, 100%) was not different (p = 0.3) than for non-EOR patients (1 and 3 years, 96%). CONCLUSIONS After the Fontan procedure, selective EOR can be performed safely and improves postoperative hemodynamics, decreases hospital resource utilization, and reduces hospital recovery time.