Erik Michelfelder

Diagnosis and Treatment of Fetal Cardiac Disease A Scientific Statement From the American Heart Association

Background— The goal of this statement is to review available literature and to put forth a scientific statement on the current practice of fetal cardiac medicine, including the diagnosis and management of fetal cardiovascular disease. Methods and Results— A writing group appointed by the American Heart Association reviewed the available literature pertaining to topics relevant to fetal cardiac medicine, including the diagnosis of congenital heart disease and arrhythmias, assessment of cardiac function and the cardiovascular system, and available treatment options. The American College of Cardiology/American Heart Association classification of recommendations and level of evidence for practice guidelines were applied to the current practice of fetal cardiac medicine. Recommendations relating to the specifics of fetal diagnosis, including the timing of referral for study, indications for referral, and experience suggested for performance and interpretation of studies, are presented. The components of a fetal echocardiogram are described in detail, including descriptions of the assessment of cardiac anatomy, cardiac function, and rhythm. Complementary modalities for fetal cardiac assessment are reviewed, including the use of advanced ultrasound techniques, fetal magnetic resonance imaging, and fetal magnetocardiography and electrocardiography for rhythm assessment. Models for parental counseling and a discussion of parental stress and depression assessments are reviewed. Available fetal therapies, including medical management for arrhythmias or heart failure and closed or open intervention for diseases affecting the cardiovascular system such as twin–twin transfusion syndrome, lung masses, and vascular tumors, are highlighted. Catheter-based intervention strategies to prevent the progression of disease in utero are also discussed. Recommendations for delivery planning strategies for fetuses with congenital heart disease including models based on classification of disease severity and delivery room treatment will be highlighted. Outcome assessment is reviewed to show the benefit of prenatal diagnosis and management as they affect outcome for babies with congenital heart disease. Conclusions— Fetal cardiac medicine has evolved considerably over the past 2 decades, predominantly in response to advances in imaging technology and innovations in therapies. The diagnosis of cardiac disease in the fetus is mostly made with ultrasound; however, new technologies, including 3- and 4-dimensional echocardiography, magnetic resonance imaging, and fetal electrocardiography and magnetocardiography, are available. Medical and interventional treatments for select diseases and strategies for delivery room care enable stabilization of high-risk fetuses and contribute to improved outcomes. This statement highlights what is currently known and recommended on the basis of evidence and experience in the rapidly advancing and highly specialized field of fetal cardiac care.

Early manifestations and spectrum of recipient twin cardiomyopathy in twin–twin transfusion syndrome: relation to Quintero stage

To examine cardiac structural and functional changes in twin–twin transfusion syndrome (TTTS), relative to Quintero stage, as a means of evaluating the spectrum of cardiomyopathy in TTTS.

Outcomes of congenital diaphragmatic hernia in the modern era of management.

OBJECTIVE To identify clinical factors associated with pulmonary hypertension (PH) and mortality in patients with congenital diaphragmatic hernia (CDH). STUDY DESIGN A prospective cohort of neonates with a diaphragm defect identified at 1 of 7 collaborating medical centers was studied. Echocardiograms were performed at 1 month and 3 months of age and analyzed at a central core by 2 cardiologists independently. Degree of PH and survival were tested for association with clinical variables using Fischer exact test, χ(2), and regression analysis. RESULTS Two hundred twenty patients met inclusion criteria. Worse PH measured at 1 month of life was associated with higher mortality. Other factors associated with mortality were need for extracorporeal membrane oxygenation, patients inborn at the treating center, and patients with a prenatal diagnosis of CDH. Interestingly, patients with right sided CDH did not have worse outcomes. CONCLUSIONS Severity of PH is associated with mortality in CDH. Other factors associated with mortality were birth weight, gestational age at birth, inborn status, and need for extracorporeal membrane oxygenation.

Prenatal Head Growth and White Matter Injury in Hypoplastic Left Heart Syndrome

Children with hypoplastic left heart syndrome (HLHS) have an increased prevalence of central nervous system (CNS) abnormalities. The extent to which this problem is due to CNS maldevelopment, prenatal ischemia, postnatal chronic cyanosis and/or multiple exposures to cardiopulmonary bypass is unknown. To better understand the etiology of CNS abnormalities in HLHS, we evaluated 68 neonates with HLHS; in 28 cases, both fetal ultrasound and echocardiogram data were available to assess head size, head growth and aortic valve anatomy (atresia or stenosis). In addition, we evaluated neuropathology in 11 electively aborted HLHS fetuses. The mean head circumference percentile in HLHS neonates was significantly smaller than HLHS fetuses (22 ± 2% versus 40 ± 4%, p < 0.001). A significant decrease in head growth, defined as a 50% reduction in head circumference percentile, was observed in half (14/28) of HLHS fetuses and nearly a quarter (6/28) were already growth restricted (≤10%) at the time of initial evaluation. Brains from HLHS fetuses demonstrated chronic diffuse white matter injury of varying severity. These patterns of prenatal head growth and brain histopathology identify a spectrum of abnormal CNS development and/or injury in HLHS fetuses.

Color M-Mode and Doppler Tissue Evaluation of Diastolic Function in Children: Simultaneous Correlation with Invasive Indices

OBJECTIVE The purpose of this study was to explore the validity of diastolic indices derived from color M-mode Doppler and Doppler tissue imaging in a heterogeneous group of pediatric patients by comparing them with simultaneously obtained invasive indices of diastolic function. METHODS A total of 20 children undergoing left heart catheterization had echocardiographic images recorded simultaneously with high-fidelity left ventricular (LV) pressure tracings. Transmitral Doppler, pulmonary vein Doppler, Doppler tissue imaging, and color M-mode Doppler flow propagation velocity were recorded. LV peak negative dP/dt, the time constant of isovolumic relaxation, and LV end-diastolic pressure were compared with the echocardiographic indices. RESULTS The ratio of peak E-wave mitral velocity/propagation velocity correlated significantly with LV end-diastolic pressure (r = 0.71; P <.001). Propagation velocity correlated with the time constant of isovolumic relaxation (r = -0.56; P =.01) and peak negative dP/dt (r = 0.50; P <.03). Septal mitral annular myocardial velocity correlated significantly with the time constant of isovolumic relaxation (r = -0.58, P =.01). CONCLUSION The newer diastolic indices derived from color M-mode Doppler and Doppler tissue imaging appear to be a helpful adjunct in the noninvasive assessment of diastolic function in children.

Persistent Diastolic Flow Reversal in Abdominal Aortic Doppler-Flow Profiles Is Associated With an Increased Risk of Necrotizing Enterocolitis in Term Infants With Congenital Heart Disease

OBJECTIVE. Diastolic runoff in the abdominal aorta, with subsequent circulatory mesenteric insufficiency, has been postulated as a cause of necrotizing enterocolitis in term infants with congenital heart disease. With this study we sought to determine whether Doppler-flow characteristics in the abdominal aorta can predict which infants are at specific risk, independent of gestational age and type of congenital heart disease. PATIENTS AND METHODS. We conducted a case-control study of term infants with congenital heart disease and proven necrotizing enterocolitis (n = 18) compared with gestational age–matched and diagnosis-matched control subjects (n = 20). Abdominal aortic Doppler velocities, time intervals, and reversals were analyzed. Groups were compared, and independent risk factors for necrotizing enterocolitis were determined. RESULTS. The groups were similar with regard to weight, pulse pressure, use of prostaglandins or inotropes, presence of a patent ductus arteriosus, and systolic function. However, 47% of the case subjects with necrotizing enterocolitis had persistent retrograde diastolic flow in the abdominal aorta compared with 15% of the control subjects. When adjusting for multiple risk factors, persistent diastolic flow reversal remained the only factor significantly associated with necrotizing enterocolitis. CONCLUSION. Persistent diastolic flow reversal in the abdominal aortic Doppler profile is associated with an increased risk of necrotizing enterocolitis in term infants with congenital heart disease irrespective of gestational age or anatomic type of congenital heart disease.

Modified Norwood operation for single left ventricle and ventriculoarterial discordance: an improved surgical technique.

BACKGROUND Patients with univentricular hearts and ventriculoarterial discordance with potentially obstructed systemic blood flow continue to pose difficult management problems. The goals of neonatal palliative operations are to control pulmonary blood flow while avoiding pulmonary artery distortion, to relieve systemic outflow tract obstruction, and to avoid heart block. METHODS Between January 1987 and December 1996, 38 patients with either tricuspid atresia or a double-inlet left ventricle and ventriculoarterial discordance underwent a modified Norwood procedure. Their mean age was 15 days, and their mean weight was 3.4 kg. Aortic arch anomalies were present in 92% of the patients. Morbidity and mortality statistics, intraoperative data, and postoperative echocardiograms were reviewed. RESULTS There were 3 early deaths (7.8%) and 5 late deaths (13.1%). The actuarial survival rates at 1 month, 1 year, and 5 years were 89%, 82%, and 71%, respectively. Follow-up was complete in all children at a mean interval of 30 +/- 9 months. None of the patients had significant neoaortic valve insufficiency, and 1 patient required therapy for residual aortic arch obstruction. Nine patients (30% of the survivors) have undergone the hemi-Fontan procedure, and 18 patients (60%) successfully have undergone the Fontan procedure. CONCLUSIONS In this patient population, we recommend the modified Norwood procedure as the neonatal palliative treatment of choice. It can be performed with acceptable early morbidity and mortality, and it improves suitability for the Fontan procedure. It reliably relieves all levels of systemic outflow tract obstruction, controls pulmonary blood flow, and avoids heart block.

Congenital Heart Disease Infant Death Rates Decrease as Gestational Age Advances from 34 to 40 Weeks

OBJECTIVES To describe congenital heart disease death rates in infants born between 34 and 40 weeks, estimate the relationship between gestational age and congenital heart disease infant death rates, and compare congenital heart disease death rates across 1- and 2-week intervals in gestational age. STUDY DESIGN The 2000 to 2003 national linked birth/infant death cohort datasets were obtained. Congenital heart disease deaths were identified by using International Statistical Classification of Diseases, 10th Revision codes. Proportional death rates were calculated by using congenital heart disease deaths and all live births. The relationship between congenital heart disease death rates and gestational age was determined. Death rates were compared across intervals. RESULTS A total of 14.9 million records were analyzed. Congenital heart disease deaths occurred in 4736 infants (0.04%) born between 34 and 40 weeks. There was a significant, negative linear relationship between congenital heart disease death rate and gestational age (R(2) = 0.97). Comparisons across 1-week intervals varied (P = .02-.23). All 2-week intervals were statistically significant (P < .01). CONCLUSIONS Congenital heart disease death rates decrease as gestational age approaches 40 weeks. These results should be considered before elective delivery for the sole indication of prenatally diagnosed congenital heart disease.

Acute effects of selective fetoscopic laser photocoagulation on recipient cardiac function in twin-twin transfusion syndrome

OBJECTIVE This study evaluated the acute effects of selective fetoscopic laser photocoagulation (SFLP) on recipient cardiovascular function in a twin-twin transfusion syndrome (TTTS) pregnancy. STUDY DESIGN This was a retrospective chart review of echocardiographic data in TTTS including right (RV) and left (LV) ventricular Doppler myocardial performance index (MPI); LV and RV end diastolic wall thickness; and umbilical artery (UA), vein (UV), and ductus venosus (DV) Dopplers. The primary outcome measures were improved MPI defined as greater than 10% interval decrease in left and/or right MPI. Data were analyzed by Student t test and Fishers exact test. RESULTS Sixty-five patients met inclusion criteria. SFLP results in a significant improvement in UV and DV Doppler and an increase in both RV and LV wall thickness. A 10% or greater improvement in recipient LV MPI after SFLP is associated with improved recipient survival as compared with unimproved LV MPI (100% vs 86.1%, P = .05). CONCLUSION Improved recipient myocardial performance index after SFLP is associated with improvement in recipient survival.

Supplementing desflurane with intravenous anesthesia reduces fetal cardiac dysfunction during open fetal surgery.

Objective:  To lower the incidence and severity of fetal cardiovascular depression during maternal fetal surgery under general anesthesia.