Is hydrops fetalis a manifestation of fetal pulmonary edema caused by impaired lymphatic drainage?

Hydrops fetalis is the final common hemodynamic pathway for a variety of fetal cardiovascular pathologies, including high-output states associated with fetal anemia or arteriovenous fistulas, and abnormalities of both cardiac structure and rhythm. Hydrops fetalis secondary to cardiovascular decompensation is usually accompanied by increases in fetal systemic venous pressure as evidenced by alterations in venous Doppler blood flow velocities. We present two cases of severe fetal aortic stenosis with left ventricular fibroelastosis and mitral regurgitation, and in-utero closure or stenosis of the foramen ovale, with severe hydrops fetalis, despite normal systemic venous Doppler flow profiles. These cases have led us to reconsider the presumed etiology of cardiovascular-based hydrops fetalis in fetuses with severely impaired left ventricular pump function and secondary mitral regurgitation. We hypothesize that raised pulmonary venous pressure, with only mildly increased central venous pressure, may impact negatively on pulmonary lymphatic flow, decrease serum oncotic pressure, increase venous hydrostatic pressure, and lead to hydrops fetalis.

Bidirectional cavopulmonary anastomosis: impact on diastolic ventricular function indices.

Systolic ventricular function has been demonstrated to remain unchanged following bidirectional cavopulmonary anastomosis (BCPA). The effects of BCPA on diastolic ventricular performance have not been critically assessed. The objective of this study was to evaluate the changes in diastolic ventricular function indices early after BCPA. Nineteen patients were enrolled prospectively. Transthoracic echocardiograms were performed at a median of 4 days prior to and 5 days subsequent to BCPA. Diastolic and systolic echocardiographic indices of ventricular performance were measured for the dominant ventricle. End diastolic volume decreased postoperatively (71.1 +/- 21.1 vs 68.08 +/- 17.9 ml/m2, p = 0.05). Tei index increased postoperatively (0.51 +/- 0.2 vs 0.62 +/- 0.1, p = 0.002), whereas inflow Doppler E velocity (70.3 +/- 13 vs 56.3 +/- 24.7 cm/sec, p = 0.04), E/A ratio (1.18 +/- 0.52 vs 0.84 +/- 0.2, p = 0.02), tissue Doppler E' velocity (9.5 +/- 2.5 vs 6.4 +/- 3.2 cm/sec, p = 0.03) and diastolic flow propagation velocity (56.5 +/- 12 vs 52.8 +/- 11 cm/sec, p = 0.04) all decreased. There was no change in ventricular mass, area change fraction, heart rate, or inflow Doppler A or tissue Doppler A' and S' velocities. This study demonstrated that diastolic indices of ventricular performance are altered indicating decreased diastolic function early following BCPA. Whether this observation is a result of a change in ventricular mass:volume ratio, loading conditions of the ventricle, ventricular geometry, or the effects of cardiopulmonary bypass remains to be determined.

Discordant anatomically corrected malposition of the great vessels and Ebstein's malformation: fetal and neonatal findings.

Discordant anatomically corrected malposition of the great vessels (ACM) is a rare congenital cardiac malformation that is often associated with other cardiac lesions. To our knowledge, a fetal diagnosis of this lesion has not yet been reported in the literature. We present a case of ACM associated with Ebstein's malformation, diagnosed by fetal echocardiography.

Echocardiographic guidance of catheter-based treatments of atrial septal defect: transesophageal echocardiography remains the gold standard.

The availability of echocardiographic imaging to the catheterization laboratory has been recognized as an essential component of every congenital heart program for almost 30 years. The imaging data that are uniquely available using this technique may be used to plan the catheterization procedure; to add insights regarding valve anatomy and chordal insertions and myocardial performance; to assist in the identification of pericardial effusions; and to provide additional guidance for the performance of pericardiocentesis.

Cardiac arrhythmias in the human fetus.

Fetal cardiac arrhythmias have been recognized with increasing frequency during the past several years. Most fetal arrythmias are intermittent extrasystoles, often presenting as irregular pauses of rhythm. These are significant only when they occur with appropriate timing to initiate sustained tachycardia, mediated by anatomic bypass pathways. The most common important fetal arrhythmias are: 1) supraventricular tachycardias, and 2) severe bradyarrhythmias, associated with complete heart block. Symptomatic fetal tachycardias are usually supraventricular in origin, and may be associated with the developmet of hydrops fetalis. These patients may respond to antiarrhythmic drug therapy, administered via maternal ingestion or via direct fetal injection. Such therapy should be offered with careful fetal and maternal monitoring, and must be based on a logical, sequential analysis of the electrical mechanism underlying the arrhythmia, and an appreciation of the pharmacology and pharmacokinetics of the maternal, placental fetal system. Bradycardia from complete heart block may either be associated with complex congential heart malformations involving the atrioventricular junction of the heart, or may present in fetuses with normal cardiac structure, in mothers with autoimmune conditions associated with high titres of anti-SS-A or anti-SS-B antibody, which cross the placenta to cause immune-related inflammatory damage to the fetal atroventricular node. This paper reviews experience with the analysis of fetal caridac rhythm, a detailed discussion of the pathophysiology of arrhythmias and their effect on the fetal circulatory system, and offers a logical framework for the construction of treatment algorithms for fetuses at risk for circulatory compromise from fetal arrhythmias.

Autoregulation of cerebral blood flow in fetuses with congenital heart disease: the brain sparing effect.

Fetuses with congenital heart disease (CHD) have circulatory abnormalities that may compromise cerebral oxygen delivery. We believe that some CHD fetuses with decreased cerebral oxygen supply have autoregulation of blood flow that enhances cerebral perfusion (brain sparing). We hypothesize that cerebral autoregulation occurs in CHD fetuses, and the degree of autoregulation is dependent on the specific CHD and correlates with intrauterine head circumferences. CHD fetuses were compared to normal fetuses. Data included cardiac diagnosis, cerebral and umbilical artery Doppler, head circumference, weight, and gestational age. The cerebral-to-placental resistance ratio (CPR) was assessed as a measure of cerebral autoregulation. CPR = cerebral/umbilical resistance index (RI) and RI = systolic-diastolic/systolic velocity (normal CPR > 1). CPR > 1 was found in 95% of normal vs 44% of CHD fetuses. The incidence of CPR < 1 was greatest in hypoplastic left or right heart fetuses. Compared to normal, cerebral RI was decreased in CHD fetuses. The CPR vs gestational age relationship, and the relationship among weight, head circumference, and CPR differed across normal and CHD fetuses. Fetuses > 2 kg with CHD and a CPR < 1 had smaller head circumferences than normal. Brain sparing occurs in CHD fetuses. Fetuses with single ventricular physiology are most affected. Inadequate cerebral flow in CHD fetuses, despite autoregulation, may alter brain growth.

Ectopic cardiac calcification associated with hyperparathyroidism in a boy with hypophosphatemic rickets.

An adolescent with hypophosphatemic rickets developed cardiac calcifications in the absence of hypercalcemia or elevation of the phosphocalcic product (the product of the total serum calcium and phosphorus concentrations). Cardiac calcifications led to aortic and mitral valve dysfunction, myocardial calcification, and arrhythmia. Hyperparathyroidism probably played a significant role in the development of this complication, which emphasizes the necessity for intermittent assessment of parathyroid status in individuals receiving medical therapy for hypophosphatemic rickets.

Prenatal diagnosis of congenital heart disease affects preoperative acidosis in the newborn patient.

OBJECTIVES: Congenital heart disease is the leading cause of death in the first year after birth. Prenatal diagnosis of the disease can optimize the preoperative condition of the patient and may help in the prevention of acidosis. In this retrospective study we compared the occurrence of metabolic acidosis in patients with and without prenatal diagnosis of a congenital heart disease. METHODS: Data of 408 patients who needed an operation for congenital heart disease within 31 days of life were analyzed retrospectively. Arterial blood gases at fixed time intervals and worst blood gas of 81 patients with and 327 patients without a prenatal diagnosis were compared, categorizing the patients on ductus dependency, anticipated univentricular or biventricular repair, and left-sided, right-sided, or no heart obstruction. RESULTS: In the overall group significant differences in lowest pH, lowest base excess, and highest lactate level were found, with metabolic acidosis more common among the patients with a postnatal diagnosis. In the group of patients with ductus-dependent congenital heart disease, the difference between patients receiving a prenatal and those receiving a postnatal diagnosis was more significant than in the group with non-ductus-dependent lesions. Analyzing patients with right-sided, left-sided, and no obstruction separately, significant differences were found in the group with left-sided heart obstruction for lowest pH and base excess and in the group with right-sided heart obstruction for lowest base excess. CONCLUSIONS: Prenatal diagnosis of congenital heart disease minimizes metabolic acidosis in patients with congenital heart disease and may be associated with improved long-term outcome and prevention of cerebral damage among this fragile group of patients, although no significant effect on direct surgical outcome was encountered.

Sotalol in the treatment of fetal dysrhythmias.

BACKGROUND: Fetal tachycardia may cause hydrops fetalis and lead to fetal death. No unanimity of opinion exists regarding the optimum treatment. This study evaluates our experience with transplacental sotalol therapy to treat fetal tachycardias in terms of safety and efficacy. METHODS AND RESULTS: The charts of 21 patients who were treated with sotalol for fetal tachycardia were reviewed. Ten fetuses had atrial flutter (AF), 10 had supraventricular tachycardia (SVT), and 1 had VT. Hydrops fetalis was present in 9 fetuses. Drug treatment was successful in establishing sinus rhythm in 8 of 10 fetuses with AF and in 6 of 10 fetuses with SVT. The mortality rate in this study was 19% (4 of 21 fetuses; 3 had SVT and 1 had AF); 3 deaths occurred just days after the initiation of sotalol therapy, and 1 occurred after a dosage increase. At birth, tachycardia was present in 6 infants. Two patients who converted to sinus rhythm in utero suffered from neurologic pathology postnatally. CONCLUSIONS: Fetal tachycardia is a serious condition in which treatment should be initiated, especially in the presence of hydrops fetalis. The high success rate in fetuses with AF suggests that sotalol should be considered a drug of first choice to treat fetal AF. The low conversion rate and the fact that 3 of the 4 deaths in this study occurred in fetuses with SVT indicate that the risks of sotalol therapy outweigh the benefits in this group and that sotalol should, therefore, be limited in the treatment of fetal SVT.

The clinical significance of the irregular fetal heart rhythm.

OBJECTIVE: Irregular fetal heart rhythms are common in clinical practice, but there is little information available on their significance or appropriate management. STUDY DESIGN: This was a retrospective review of fetuses seen during 10 years that either were referred for fetal echocardiography because of a fetal arrhythmia or were found incidentally to have an arrhythmia during fetal echocardiography for other indications. RESULTS: From 1988 through 1997 we performed 5566 fetal echocardiograms on 4838 different fetuses. There were 614 fetuses with irregular fetal heart rhythms. Among 595 referred for arrhythmias, extrasystoles were found in 255 (42.9%), normal rhythms were seen in 330 (55.4%), and hemodynamically significant arrhythmias were seen in 10. There were 2 fetuses with arrhythmias and structural heart disease. Nine of 10 fetuses with hemodynamically significant arrhythmias survived. An additional five neonates were found to have hemodynamically significant arrhythmias only postnatally. A total of 15 fetuses (2. 4%) among those referred for irregular rhythms had significant arrhythmias. CONCLUSIONS: Irregular fetal heart rhythms signify hemodynamically significant arrhythmias in a small but important proportion of fetuses. Those without persistent irregularities on evaluation can be followed up with routine prenatal care.

Atrial flutter in the perinatal age group: diagnosis, management and outcome.

OBJECTIVES: The aim of this retrospective study was to evaluate perinatal atrial flutter (AF) and the efficacy of maternally administered antiarrhythmic agents, postpartum management and outcome. BACKGROUND: Perinatal AF is a potentially lethal arrhythmia, and management of this disorder is difficult and controversial. METHODS: Forty-five patients with documented AF were studied retrospectively. RESULTS: Atrial flutter was diagnosed prenatally in 44 fetuses and immediately postnatally in 1 neonate. Fetal hydrops was seen in 20 patients; 17 received maternal therapy, 2 were delivered and 1 was not treated because it had a severe nontreatable cardiac malformation. In the nonhydropic group of 24 patients, 18 were treated and the remaining 6 were delivered immediately. In the hydropic group, 10 received single-drug therapy (digoxin or sotalol) and 7 received multidrug therapy. In the nonhydropic group, 13 received a single drug (digoxin or sotalol) and 5 received multiple drugs. One patient with rapid 1:1 atrioventricular conduction (heart rate 480 beats/min) died in utero and another died due to a combination of severe hydrops because of the AF, sotalol medication, stenosis of the venous duct and hypoplastic placenta. Of the 43 live-born infants, 12 were in AF at birth. Electrical cardioversion was successful in eight of nine patients. No recurrences in AF have occurred beyond the neonatal period. Four patients with fetal flutter and hydrops showed significant neurological pathology immediately after birth. CONCLUSIONS: Fetal AF is a serious and threatening rhythm disorder, particularly when it causes hydrops, it may be associated with fetal death or neurological damage. Treatment is required and primarily aimed at reaching an adequate ventricular rate and preferably conversion to sinus rhythm. Digoxin failed in prevention of recurrence at time of delivery in a quarter of our patients, whereas with sotalol no recurrence of AF has been reported, suggesting that class III agents may be the future therapy. Once fetuses with AF survive without neurological pathology, their future is good and prophylaxis beyond the neonatal period is unnecessary.

Nurse executives: new roles, new opportunities.

As women have been nursing since the earliest days of recorded civilization, so nurses have been associated with health care since the earliest days of recorded medical history. Gender and function have been inextricably woven in ways that created a struggle for success within a male-dominated industry. Nurses, as women, have been undervalued as, until recently, their role in health care has been similarly undervalued. Changing realities in the health care environment have created an opportunity for women's unique skills and talents to be revalued in a way that offers new opportunities for nurses. Teamwork, global thinking, multitasking, creativity, and flexibility are characteristics that have assumed new importance in the marketplace. Nursing leaders possess these attributes, along with a strong clinical foundation that is integrated with knowledge of sound business principles. This combination now positions nurse executives to reach the highest levels of heath care administration. Critical to this achievement is the professional credibility obtained through education at the master's degree level in health care and nursing administration programs that provide the essential tools for professional success. New opportunities for nurse executives afford educators in health care and nursing administration similar opportunities to develop and market programs to this large group of health care professionals who are seeking graduate education in increasing numbers.

Inhaled nitric oxide therapy in a critically ill neonate with Ebstein's anomaly.

The successful use of nitric oxide (NO) inhalation in a critically ill neonate with Ebstein's anomaly of the tricuspid valve is reported for the first time. This use of inhaled NO therapy suggests a therapeutic intervention that directly addresses the pathophysiologic process of severe neonatal Ebstein's anomaly.

Aortic stenosis and patent ductus arteriosus: pressure gradients pre- and posttranscatheter ductal occlusion.

Three patients with patent ductus arteriosus and moderate aortic stenosis had a marked reduction in aortic valve gradient following transcatheter ductal occlusion. The hemodynamic effects of an aortopulmonary shunt on the severity of left ventricular outflow obstruction and the implications on intervention are discussed.

Does a prenatal diagnosis of congenital heart disease alter short-term outcome?

Congenital heart disease (CHD) is the most common fatal congenital anomaly in the first year after birth. Fetal echocardiography has become accepted as a method of diagnosing CHD in utero, but the benefits of prenatal diagnosis have not been evaluated. We performed a cohort analysis of neonates with CHD in the absence of other life-threatening conditions. One group (I) consisted of neonates who had been diagnosed as fetuses to have CHD and who were delivered at Yale-New Haven Hospital. The other group (II) consisted of neonates who were not diagnosed to have CHD until after birth, and were either delivered at, or transferred to, the same hospital. Costs of initial hospitalization, length of hospitalization, and survival to discharge home with the parents were primary outcome measures. Our primary hypothesis was that all outcome measures would be improved by prenatal diagnosis. We also examined secondary hypotheses that these same measures would be improved among selected subgroups, including those requiring univentricular management, those amenable to biventricular repair, those with ductal dependent lesions, and those requiring any surgery during the primary admission. From January 1, 1991 to June 30, 1996 we identified 45 antenatal cases and 54 postnatal cases of CHD that met the study entry criteria. The median length (+/- SE) of initial hospitalization was 16 +/- 3.8 days in group I, and 11 +/- 3.8 days in group II (p < 0.08). The median cost of initial hospitalization was $57,678 +/- 12,340 vs. $53,604 +/- 7249 (not significant). Eighty percent of group I survived to hospital discharge compared with 67% of group II (p = 0.14). There was no difference in survival among those requiring univentricular management (64 vs. 44%), but costs and length of hospitalization were greater in group I, regardless of whether or not surgery was performed postnatally. Surgery was undertaken more often among the prenatal diagnosis group with univentricular hearts (86 vs. 56%, p < 0.05). Among those fetuses amenable to biventricular repair, survival was better (96 vs. 76%, p < 0.05) and the cost of hospitalization was lower ($30,277 +/- 16,869 vs. $64,616 +/- 9441, p = 0.06) in the prenatal diagnosis group. Prenatal diagnosis of CHD does not result in the expected savings in cost, length of hospitalization or survival in the overall group of patients. The prenatal diagnosis group showed a skew towards single ventricle physiology. Within that group a high rate of pregnancy termination results in a group of parents who are likely to choose postnatal surgery despite high short- and long-term mortality risks.

Management of fetal cardiac arrhythmias.

While most fetal cardiac arrhythmias are benign in nature, some may be dangerous and require prenatal treatment. This article reviews the differential diagnoses of fetal tachycardias and bradycardias, as well as treatment and management approaches.

Thromboembolic complications after Fontan operations.

BACKGROUND: Despite the increasing recognition of thromboembolic complications of the Fontan procedure, data characterizing such events are limited. The total cavopulmonary connection is believed to be less prone to this complication than other modifications of Fontan operations. We examined our experience with thromboembolism after Fontan operations to better characterize these events and their relation to the type of Fontan operation performed. METHODS AND RESULTS: We retrospectively identified 70 patients who underwent a Fontan operation between January 1978 and March 1994. Patients were divided into three groups: (1) total cavopulmonary connection, (2) atriopulmonary connection, and (3) conduit interposition. Fourteen patients (20%) developed a thromboembolic complication during a mean (+/- SD) follow-up of 5.2 +/- 4.7 years. The rate of thrombosis was similar in each group. The time from Fontan operation to thrombosis averaged 6.1 +/- 5.0 years. The overall rate of thromboembolic events was 3.9 per 100 patient-years. Twelve of the 14 thrombi were located within the venous circulation, 1 was in the left ventricle, and the location of 1 was undetermined. Six of the patients (43%) were asymptomatic, 3 (21%) presented with cerebrovascular events, and 5 (36%) presented with other symptoms. Thromboembolic events occurred from the perioperative period to 15 years after surgery. CONCLUSIONS: Thromboembolic complications occur frequently after the Fontan operation and its modifications and are a cause of significant morbidity. The time of presentation varies greatly. The rate of thrombosis appears to be similar in all modifications of the Fontan operation.

Successful in utero therapy of fetal heart block.

OBJECTIVE: Congenital complete heart block is associated with maternal autoantibodies to Ro and La proteins, which injure the fetal cardiac conduction system. We administered dexamethasone to the mothers of five fetuses with heart block caused by maternal antibodies. STUDY DESIGN: We diagnosed five cases of fetal heart block at 20 to 23 weeks and treated all mothers with dexamethasone 4 mg orally each day for the remainder of the pregnancy. All patients were positive for anti-SS-A (anti-Ro) and/or anti-SS-B (anti-La) antibodies. RESULTS: Four patients had complete heart block, and one had second-degree block. In two patients (one with complete heart block, one with second-degree heart block) the degree of block lessened with treatment. Hydrops in three complete heart block patients resolved after treatment. Maternal antibody levels did not change. Matched maternal and cord samples at delivery showed similar antibody levels. CONCLUSIONS: Complete heart block can respond to transplacental glucocorticoid therapy with improved cardiac conduction. Because there may be a concurrent myocarditis, treatment in utero may also improve cardiac contractility, leading to the observed rapid resolution of hydrops. Treatment with steroids that cross the placenta should be considered for newly diagnosed cases of complete heart block with positive antibody screens.