The American Association for Thoracic Surgery (AATS) 2024 expert consensus document: Management of neonates and infants with Ebstein anomaly

OBJECTIVES

Symptomatic neonates and infants with Ebstein anomaly (EA) require complex management. A group of experts was commissioned by the American Association for Thoracic Surgery to provide a framework on this topic focusing on risk stratification and management.

METHODS

The EA Clinical Congenital Practice Standards Committee is a multinational and multidisciplinary group of surgeons and cardiologists with expertise in EA. A citation search in PubMed, Embase, Scopus, and Web of Science was performed using key words related to EA. The search was restricted to the English language and the year 2000 or later and yielded 455 results, of which 71 were related to neonates and infants. Expert consensus statements with class of recommendation and level of evidence were developed using a modified Delphi method, requiring 80% of members votes with at least 75% agreement on each statement.

RESULTS

When evaluating fetuses with EA, those with severe cardiomegaly, retrograde or bidirectional shunt at the ductal level, pulmonary valve atresia, circular shunt, left ventricular dysfunction, or fetal hydrops should be considered high risk for intrauterine demise and postnatal morbidity and mortality. Neonates with EA and severe cardiomegaly, prematurity (<32 weeks), intrauterine growth restriction, pulmonary valve atresia, circular shunt, left ventricular dysfunction, or cardiogenic shock should be considered high risk for morbidity and mortality. Hemodynamically unstable neonates with a circular shunt should have emergent interruption of the circular shunt. Neonates in refractory cardiogenic shock may be palliated with the Starnes procedure. Children may be assessed for later biventricular repair after the Starnes procedure. Neonates without high-risk features of EA may be monitored for spontaneous closure of the patent ductus arteriosus (PDA). Hemodynamically stable neonates with significant pulmonary regurgitation at risk for circular shunt with normal right ventricular systolic pressure should have an attempt at medical closure of the PDA. A medical trial of PDA closure in neonates with functional pulmonary atresia and normal right ventricular systolic pressure (>20-25 mm Hg) should be performed. Neonates who are hemodynamically stable without pulmonary regurgitation but inadequate antegrade pulmonary blood flow may be considered for a PDA stent or systemic to pulmonary artery shunt.

CONCLUSIONS

Risk stratification is essential in neonates and infants with EA. Palliative comfort care may be reasonable in neonates with associated risk factors that may include prematurity, genetic syndromes, other major medical comorbidities, ventricular dysfunction, or sepsis. Neonates who are unstable with a circular shunt should have emergent interruption of the circular shunt. Neonates who are unstable are most commonly palliated with the Starnes procedure. Neonates who are stable should undergo ductal closure. Neonates who are stable with inadequate pulmonary flow may have ductal stenting or a systemic-to-pulmonary artery shunt. Subsequent procedures after Starnes palliation include either single-ventricle palliation or biventricular repair strategies.

Anatomic considerations in the management of complete atrioventricular canal

OBJECTIVE

Patients with complete atrioventricular canal have a variable clinical course prior to repair. Many patients balance their circulations well prior to elective repair. Others manifest clinically significant pulmonary over circulation early in life and require either palliative pulmonary artery banding or complete repair. The objective of this study was to assess anatomic features that impact the clinical course of patients.

METHODS

In total, 222 patients underwent complete atrioventricular canal repair between 2012 and 2022 at a single institution. Twenty-seven (12%) patients underwent either pulmonary artery banding (n = 15) or complete repair (n = 12) at less than 3 months of age (Group 1). The remaining 195 (88%) underwent repair after 3 months of age (Group 2). Patient records and imaging were reviewed.

RESULTS

The median post-operative length of stay following complete repair was 25 [7,46] days for those patients in Group 1 and 7 [5,12] days for those in Group 2 (p < 0.0001). There was relative hypoplasia of left-sided structures in Group 1 versus Group 2. Mean z-score for the ascending aorta was -1.2 (±0.8) versus -0.3 (±0.9) (p < 0.0001), the aortic isthmus was -2.1 (±0.8) versus -1.4 (±0.8) (p = 0.005). The pulmonary valve to aortic valve diameter ratio was median 1.47 [1.38,1.71] versus 1.38 [1.17,1.53] (p 0.008).

CONCLUSIONS

Echocardiographic evaluation of the systemic and pulmonary outflow of patients with complete atrioventricular canal may assist in predicting the clinical course and need for early repair vs pulmonary artery banding.

Evaluation of Fontan-associated Liver Disease and Ethnic Disparities in Long-term Survivors of the Fontan Procedure: A Population-based Study

OBJECTIVES

Fontan-associated liver disease (FALD) has emerged as a nearly universal chronic comorbidity in patients with univentricular congenital heart disease who undergo the Fontan procedure. There is a paucity of data reporting long-term outcomes and the impact of FALD in this population.

METHODS

Patients who underwent the Fontan procedure between 1992 and 2018 were identified using California registry data. Presumed FALD was assessed by a composite of liver disease codes. Primary outcomes were mortality and transplant. Multivariable regression and survival analyses were performed.

RESULTS

Among 1436 patients post-Fontan, 75.9% studied were adults, with a median follow-up of 12.6 (8.4, 17.3) years. The population was 46.3% Hispanic. Overall survival at 20 years was >80%, but Hispanic patients had higher mortality risk compared with White patients [hazard ratio: 1.49 (1.09-2.03), P =0.012]. Only 225 patients (15.7%) had presumed FALD, although >54% of patients had liver disease by age 25. FALD was associated with later deaths [median: 9.6 (6.4-13.2) years post-Fontan] compared with patients who died without liver disease [4.1 (1.4-10.4) years, P =0.02]. Patients with FALD who underwent combined heart liver transplant had 100% survival at 5 years, compared with only 70.7% of patients who underwent heart transplant alone.

CONCLUSIONS

In this population-based analysis of long-term outcomes post-Fontan, Hispanic ethnicity was associated with increased all-cause mortality. Further, the prevalence of FALD is underrecognized, but our data confirms that its incidence increases with age. FALD is associated with late mortality but excellent posttransplant survival. This emphasizes the need for FALD-specific liver surveillance strategies in patients post-Fontan.

Comparison of a Complete Percutaneous Versus Surgical Approach to Aortic Valve Replacement and Revascularization in Patients at Intermediate Surgical Risk: Results From the Randomized SURTAVI Trial

BACKGROUND

For patients with severe aortic stenosis and coronary artery disease, the completely percutaneous approach to aortic valve replacement and revascularization has not been compared with the standard surgical approach.

METHODS

The prospective SURTAVI trial (Safety and Efficiency Study of the Medtronic CoreValve System in the Treatment of Severe, Symptomatic Aortic Stenosis in Intermediate Risk Subjects Who Need Aortic Valve Replacement) enrolled intermediate-risk patients with severe aortic stenosis from 87 centers in the United States, Canada, and Europe between June 2012 and June 2016. Complex coronary artery disease with SYNTAX score (Synergy Between PCI with Taxus and Cardiac Surgery Trial) >22 was an exclusion criterion. Patients were stratified according to the need for revascularization and then randomly assigned to treatment with transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR). Patients assigned to revascularization in the TAVR group underwent percutaneous coronary intervention, whereas those in the SAVR group had coronary artery bypass grafting. The primary end point was the rate of all-cause mortality or disabling stroke at 2 years.

RESULTS

Of 1660 subjects with attempted aortic valve implants, 332 (20%) were assigned to revascularization. They had a higher Society of Thoracic Surgeons risk score for mortality (4.8±1.7% versus 4.4±1.5%; P<0.01) and were more likely to be male (65.1% versus 54.2%; P<0.01) than the 1328 patients not assigned to revascularization. After randomization to treatment, there were 169 patients undergoing TAVR and percutaneous coronary intervention, 163 patients undergoing SAVR and coronary artery bypass grafting, 695 patients undergoing TAVR, and 633 patients undergoing SAVR. No significant difference in the rate of the primary end point was found between TAVR and percutaneous coronary intervention and SAVR and coronary artery bypass grafting (16.0%; 95% CI, 11.1-22.9 versus 14.0%; 95% CI, 9.2-21.1; P=0.62), or between TAVR and SAVR (11.9%; 95% CI, 9.5-14.7 versus 12.3%; 95% CI, 9.8-15.4; P=0.76).

CONCLUSIONS

For patients at intermediate surgical risk with severe aortic stenosis and noncomplex coronary artery disease (SYNTAX score ≤22), a complete percutaneous approach of TAVR and percutaneous coronary intervention is a reasonable alternative to SAVR and coronary artery bypass grafting.

CLINICAL TRIAL REGISTRATION

URL: https://www.

CLINICALTRIALS

gov. Unique identifier: NCT01586910.

Cardiovascular Computed Tomographic Angiography as a Virtual Patient Avatar for Individualized Surgical Planning of Complex Anomalous Coronary Artery Anatomy

Cardiovascular computed tomographic angiography (CCTA) 3-D thoracic reconstruction can serve as a "virtual patient avatar" providing surgical views for approach to complex anomalous coronary artery anatomy. Images demonstrated a single coronary artery ostium arising from the right aortic sinus with trifurcation into a prepulmonic left anterior descending coronary artery (LAD), an interarterial circumflex with a subsequent intraseptal course, and normal course of the right coronary artery. Virtual 3-D CCTA reconstructions were important to planning an incisional plane for surgical correction.

Late onset cardiac cirrhosis and portal hypertensive ascites after atrial fibrillation ablation

Pulmonary vein stenosis is a potential complication following catheter ablation of atrial fibrillation (AF). We report the case of a patient with refractory ascites late after multiple catheter ablation procedures for AF. This is the first case report of portal hypertensive ascites due to acquired multiple pulmonary vein stenoses resulting in pulmonary hypertension (PH) and cardiac cirrhosis late after AF ablation. Despite extensive surgical reconstruction of the affected pulmonary veins, the patient has PH and right heart failure with persistent ascites and lower extremity edema.

Neurological Events Following Transcatheter Aortic Valve Replacement and Their Predictors: A Report From the CoreValve Trials

BACKGROUND

The risk for stroke after transcatheter aortic valve replacement (TAVR) is an important concern. Identification of predictors for stroke is likely to be a critical factor aiding patient selection and management as TAVR use becomes widespread.

METHODS AND RESULTS

Patients enrolled in the CoreValve US Extreme Risk and High Risk Pivotal Trials or Continued Access Study treated with the self-expanding CoreValve bioprosthesis were included in this analysis. The 1-year stroke rate after TAVR was 8.4%. Analysis of the stroke hazard rate identified an early phase (0-10 days; 4.1% of strokes) and a late phase (11-365 days; 4.3% of strokes). Baseline predictors of early stroke included National Institutes of Health stroke scale score >0, prior stroke, prior transient ischemic attack, peripheral vascular disease, absence of prior coronary artery bypass surgery, angina, low body mass index (<21 kg/m(2)), and falls within the past 6 months. Significant procedural predictors were total time in the catheterization laboratory or operating room, delivery catheter in the body time, rapid pacing used during valvuloplasty, and repositioning of the prosthesis. Predictors of stroke between 11 and 365 days were small body surface area, severe aortic calcification, and falls within the past 6 months. There were no significant imaging predictors of early or late stroke.

CONCLUSIONS

Predictors of early stroke after TAVR included clinical and procedural factors; predictors of later stroke were limited to patient but not anatomic characteristics. These findings indicate that further refinement of imaging to identify anatomic factors predisposing to embolization may help improve stroke prediction in patients undergoing TAVR.

CLINICAL TRIAL REGISTRATIONS

URL: http://www.clinicaltrials.gov. Unique identifiers: NCT01240902, NCT01531374.

Anomalous Coronary Arteries

Cardiovascular computed tomographic angiography (CCTA) provides an understanding of the three-dimensional (3D) coronary artery anatomy in relation to cardiovascular thoracic structures important to the surgical management of anomalous coronary arteries (ACAs). Although some ACA variants are not clinically significant, others can lead to ischemia/infarction, related acute ventricular dysfunction, ventricular arrhythmias, and sudden cardiac death. The CCTA is important to surgical decision making, as it provides noninvasive visualization of the coronary arteries with (1) assessment of origin, course, and termination of coronary artery anomalies in the context of 3D thoracic anatomy, (2) characterization of anatomy helpful for differentiation of benign versus hemodynamically significant variants, (3) identification of other cardiothoracic anomalies, and (4) detection of coronary artery disease. High-risk ACA anatomy in the appropriate clinical setting can require surgical intervention with decisions including minimally invasive versus open sternotomy approach, correction via reimplantation of a coronary artery, alteration of the ACA course without reimplantation, or bypass of an ACA. Given the rarity of ACA, there is limited data in the literature, and significant controversy related to the management issues. The management of ACA requires comprehensive clinical history, thorough assessment of cardiac function, and detailed anatomic imaging. Future studies will need to address the long-term outcome based on detailed assessment of original anatomy and surgical approach.

Unoperated Congenitally Corrected Transposition of the Great Arteries, Nonrestrictive Ventricular Septal Defect, and Pulmonary Stenosis in Middle Adulthood

Submitted May 6, 2011; Accepted August 3, 2011. The survival into adulthood of patients with unoperated complex congenital heart disease with anomalies often considered life threatening in infancy and childhood requires a complex interplay of “balanced” defects allowing for cardiovascular physiology compatible with long-term survival. We report on a series of three cases from our advanced imaging database of middle-aged adults presenting with multiple similar defects providing a hemodynamically balanced circulation. The constellation of defects seen in each of these patients included congenitally corrected transposition of the great arteries, a large nonrestrictive ventricular septal defect, valvular pulmonary stenosis, and in two cases anomalous coronary arteries. Cardiovascular computed tomographic angiography (CCTA) and cardiovascular magnetic resonance imaging (CMR) were important to the characterization of the multiple defects and their three-dimensional relationships in these cases. Treatment decisions in patients with this constellation of findings are challenging, given the limited data due to the rarity of survival of patients with these defects into middle adulthood and the paucity of data related to decisions and approaches to medical management, surgical correction, or transplantation.

All cardiac right ventricular outpouches are not created equal

Congenital right ventricular diverticula and aneurysms are rare. Clinically, a diverticulum is difficult to distinguish from an aneurysm. Four diverse right ventricular cameral defects or right ventricular outpouches (RVOs) are described together with the management of each. Surgery may be necessary if an RVO has thin walls. However, if an RVO is composed of uniform thick contractile walls, conservative follow-up care likely is appropriate.

Risk factors for persistent pleural effusions after the extracardiac Fontan procedure

OBJECTIVE

Pleural effusions after the Fontan operation contribute significantly to morbidity and prolonged hospitalization. This study investigates the association between selected preoperative, operative, and postoperative variables and persistent pleural effusions after the extracardiac Fontan procedure.

METHODS

We conducted a retrospective study of extracardiac Fontan procedures. The variables analyzed as potential risk factors included age and weight at the time of the operation, anatomic diagnosis, preoperative oxygen saturation, mean pulmonary artery pressure, ventricular end-diastolic pressure, presence of an accessory source of pulmonary blood flow, presence of significant aortopulmonary collateral vessels, presence of fenestration, cardiopulmonary bypass time, conduit size, postoperative pulmonary artery pressure, use of angiotensin-converting enzyme inhibitors, and presence of postoperative infection. The outcome measures evaluated were duration and volume of chest tube drainage after surgical intervention.

RESULTS

From June 1997 to August 2002, 100 consecutive patients underwent the extracardiac Fontan procedure. The median age at operation was 3.1 years. The median duration of chest tube drainage was 10 days, and the median volume of drainage was 14.7 mL.kg(-1).d(-1). As determined by means of multivariate analysis, significant risk factors for pleural effusions lasting more than 2 weeks were lower preoperative oxygen saturation (P =.011) and the presence of postoperative infections (P =.003). Significant risk factors for pleural effusions draining at more than 20 mL.kg(-1).d(-1) were lower preoperative oxygen saturation (P =.005), smaller conduit size (P =.04), and longer duration of cardiopulmonary bypass (P =.004).

CONCLUSIONS

Lower preoperative oxygen saturation, presence of postoperative infection, smaller conduit size, and longer duration of cardiopulmonary bypass were associated with persistent pleural effusions after the extracardiac Fontan procedure. Modifications of some of these risk factors might influence the duration and volume of pleural drainage after surgical intervention.

Endothelial monocyte activating polypeptide II inhibits lung neovascularization and airway epithelial morphogenesis

Neovascularization is crucial to lung development and is mediated through a variety of angiogenic and anti-angiogenic factors. Herein, we show that excess Endothelial Monocyte Activating Polypeptide (EMAP) II, an anti-angiogenic protein, not only inhibits fetal lung neovascularization, but also significantly alters airway epithelial morphogenesis. In a murine allograft model of lung neovascularization and morphogenesis, embryonic lungs transplanted under the skin of immunocompromised mice receiving intraperitoneal EMAP II, had a 56% reduction in vessel density (P<0.0001) compared to control. EMAP II treated lung transplants also exhibited a marked alteration in lung morphogenesis, including lack of type II alveolar cell formation, determined by markedly decreased expression of surfactant protein C, and increased apoptosis. In contrast, lung implants in animals receiving an EMAP II blocking antibody had an increase in vessel density of 50% (P<0.0001) and increased expression of surfactant protein C mRNA in distal epithelium. These studies demonstrate that EMAP II negatively modulates lung neovascularization as well as leading to the arrest of lung airway epithelial morphogenesis and apoptosis.

Angiogenesis and morphogenesis of murine fetal distal lung in an allograft model

Neovascularization is crucial to lung morphogenesis; however, factors determining vessel growth and formation are poorly understood. The goal of our study was to develop an allograft model that would include maturation of the distal lung, thereby ultimately allowing us to study alveolar development, including microvascular formation. We transplanted 14-day gestational age embryonic mouse lung primordia subcutaneously into the back of nude mice for 3.5-14 days. Lung morphogenesis and neovascularization were evaluated by light microscopy, in situ hybridization, and immunohistochemical techniques. Embryonic 14-day gestational age control lungs had immature structural features consistent with pseudoglandular stage of lung development. In contrast, 14 days after subcutaneous transplantation of a 14-day gestational age lung, the allograft underwent significant structural morphogenesis and neovascularization. This was demonstrated by continued neovascularization and cellular differentiation, resulting in mature alveoli similar to those noted in the 2-day postnatal neonatal lung. Confirmation of maturation of the allograft was provided by progressive type II epithelial cell differentiation as evidenced by enhanced local expression of mRNA for surfactant protein C and a threefold (P < 0.008) increase in vessel formation as determined by immunocytochemical detection of platelet endothelial cell adhesion molecule-1 expression. Using the tyrosine kinase Flk-1 receptor (flk-1) LacZ transgene embryos, we determined that the neovascularization within the allograft was from the committed embryonic lung endothelium. Therefore, we have developed a defined murine allograft model that can be used to study distal lung development, including neovascularization. The model may be useful when used in conjunction with an altered genetic background (knockout or knock in) of the allograft and has the further decided advantage of bypassing placental barriers for introduction of pharmacological agents or DNA directly into the lung itself.

Angiotensin II has multiple profibrotic effects in human cardiac fibroblasts

BACKGROUND

Angiotensin II (Ang II) is implicated in cardiac remodeling and is increasingly recognized for its profibrotic activity.

METHODS AND RESULTS

Because little is known about the direct cellular effects of Ang II on human cardiac fibroblasts, we isolated fibroblasts from ventricles of explanted human hearts and added Ang II (100 nmol/L) to determine its role in growth, extracellular matrix accumulation, and adhesion. To assess which Ang II receptor is involved, Ang II was added in the presence of irbesartan (10 micromol/L), a specific AT(1) receptor antagonist; PD 123319 (10 micromol/L), a specific AT(2) receptor antagonist, or divalinil (100 nmol/L), an AT(4) receptor inhibitor. In human ventricles (n=13), message levels of atrial natriuretic peptide and AT(1) receptor were inversely correlated, which suggests a decrease in AT(1) receptor expression with progressive heart failure. Northern analysis and fluorescence-activated cell sorting demonstrated AT(1) receptor in cultured human cardiac fibroblasts. Ang II increased mitogen-activated protein kinase activity and in DNA synthesis (5-fold, P<0.01) stimulated a 2-fold increase in transforming growth factor-beta(1) (P<0.05) mRNA levels at 2 hours and a 2-fold increase in laminin (P<0.05) and fibronectin (P<0.05) mRNA levels at 24 hours. Ang II also enhanced plasminogen activator inhibitor-1 expression, which inhibits metalloproteinases that degrade the extracellular matrix. All of these effects were inhibited by irbesartan but not PD 123319 or divalinil. In addition, Ang II increased cardiac fibroblast attachment to collagens I and III, which was associated with an increase in focal adhesion kinase activity.

CONCLUSIONS

Activation of the AT(1) receptor in human heart promotes fibrosis. Ang II plays a novel role in stimulation of plasminogen activator inhibitor-1 expression and adhesion of cardiac fibroblasts to collagen.

The human antibody response to porcine xenoantigens is encoded by IGHV3-11 and IGHV3-74 IgVH germline progenitors

Preformed and induced Ab responses present a major immunological barrier to the use of pig organs for human xenotransplantation. We generated IgM and IgG gene libraries established from lymphocytes of patients treated with a bioartificial liver (BAL) containing pig hepatocytes and used these libraries to identify IgVH genes that encode human Ab responses to pig xenoantigens. Genes encoded by the VH3 family are increased in expression in patients following BAL treatment. cDNA libraries representing the VH3 gene family were generated, and the relative frequency of expression of genes used to encode the Ab response was determined at days 0, 10, and 21. Ig genes derived from the IGHV3-11 and IGHV3-74 germline progenitors increase in frequency post-BAL. The IGHV3-11 gene encodes 12% of VH3 cDNA clones expressed as IgM Abs at day 0 and 32.4-39.0% of cDNA clones encoding IgM Abs in two patients at day 10. IGHV3-11 and IGHV3-74 genes encoding IgM Abs in these patients are expressed without evidence of somatic mutation. By day 21, an isotype switch occurs and IGHV3-11 IgVH progenitors encode IgG Abs that demonstrate somatic mutation. We cloned these genes into a phagemid vector, expressed these clones as single-chain Abs, and demonstrated that the IGHV3-11 gene encodes Abs with the ability to bind to the gal alpha (1,3) gal epitope. Our results demonstrate that the xenoantibody response in humans is encoded by IgVH genes restricted to IGHV3-11 and IGHV3-74 germline progenitors. IgM Abs are expressed in germline configuration and IgG Abs demonstrate somatic mutations by day 21.

The Human Antibody Response to Porcine Xenoantigens Is Encoded by IGHV3-11 and IGHV3-74 IgVH Germline Progenitors

Preformed and induced Ab responses present a major immunological barrier to the use of pig organs for human xenotransplantation. We generated IgM and IgG gene libraries established from lymphocytes of patients treated with a bioartificial liver (BAL) containing pig hepatocytes and used these libraries to identify IgVH genes that encode human Ab responses to pig xenoantigens. Genes encoded by the VH3 family are increased in expression in patients following BAL treatment. cDNA libraries representing the VH3 gene family were generated, and the relative frequency of expression of genes used to encode the Ab response was determined at days 0, 10, and 21. Ig genes derived from the IGHV3-11 and IGHV3-74 germline progenitors increase in frequency post-BAL. The IGHV3-11 gene encodes 12% of VH3 cDNA clones expressed as IgM Abs at day 0 and 32.4–39.0% of cDNA clones encoding IgM Abs in two patients at day 10. IGHV3-11 and IGHV3-74 genes encoding IgM Abs in these patients are expressed without evidence of somatic mutation. By day 21, an isotype switch occurs and IGHV3-11 IgVH progenitors encode IgG Abs that demonstrate somatic mutation. We cloned these genes into a phagemid vector, expressed these clones as single-chain Abs, and demonstrated that the IGHV3-11 gene encodes Abs with the ability to bind to the gal α (1,3) gal epitope. Our results demonstrate that the xenoantibody response in humans is encoded by IgVH genes restricted to IGHV3-11 and IGHV3-74 germline progenitors. IgM Abs are expressed in germline configuration and IgG Abs demonstrate somatic mutations by day 21.

EMAP II: a modulator of neovascularization in the developing lung

Neovascularization is a key regulatory process in fetal growth and development. Although factors promoting growth and development of the pulmonary vasculature have been investigated, nothing is known regarding the molecular mechanisms that may counteract these stimuli. Endothelial monocyte-activating polypeptide (EMAP) II has recently been identified as an antiangiogenic factor in tumor vascular development. We postulated that EMAP II is a putative negative modulator of lung vascular growth. EMAP II mRNA and protein decrease fivefold (P < 0.01) as the developing lungs in the fetal mouse progress from having poor vascularization (day 14) to having complete vascular development at term (day 18.5). EMAP II protein expression continues to remain low throughout postnatal life and into adulthood, with the exception of a surge that correlates with microvascular maturation. Furthermore, through the use of in situ hybridization and immunohistochemistry, EMAP II is localized throughout the lung, with significant expression in the submyoepithelial area during the early stages of lung development when there is minimal vascular development. In contrast, EMAP II is distributed around the large vessels during the end of vascular development, suggesting that EMAP II modulates the neovascularization process. We speculate that EMAP II is a director of neovascularization in the developing lung.

Laparoscopic fundoplication 1 month prior to lung transplantation

Upper midline laparotomy in the presence of pulmonary failure is often complicated by a prolonged period of mechanical ventilation postoperatively. We report the successful performance of laparoscopic fundoplication, without ventilatory support, in a woman with end stage pulmonary disease and resting hypercarbia, one month prior to lung transplantation.

A controlled trial of ganciclovir to prevent cytomegalovirus disease after heart transplantation

BACKGROUND

Because of the immunosuppression required, heart-transplant recipients frequently have complications caused by cytomegalovirus (CMV), including pneumonia, esophagitis, gastritis, and a syndrome of fever, hepatitis, and leukopenia. We undertook a controlled trial to evaluate the prophylactic administration of ganciclovir to prevent CMV-induced disease after heart transplantation.

METHODS

This randomized, double-blind, placebo-controlled trial was conducted at four centers. Before randomization, the patients were stratified into two groups: those who were seropositive for CMV before transplantation and those who were seronegative but who received hearts from seropositive donors. Ganciclovir was given intravenously at a dose of 5 mg per kilogram of body weight every 12 hours from postoperative day 1 through day 14, then at a dose of 6 mg per kilogram each day for 5 days per week until day 28.

RESULTS

Among the seropositive patients, CMV illness occurred during the first 120 days after heart transplantation in 26 of 56 patients given placebo (46 percent), as compared with 5 of 56 patients treated with ganciclovir (9 percent) (P less than 0.001). Among 37 seronegative patients, CMV illness was frequent in both groups (placebo, 29 percent; ganciclovir, 35 percent; P not significant). From day 15 through day 60, the patients who took ganciclovir had significantly fewer urine cultures positive for CMV, but by day 90 there was no difference. More of the ganciclovir-treated patients had serum creatinine concentrations greater than or equal to 221 mumol per liter (2.5 mg per deciliter) (18 percent vs. 4 percent in the placebo group), but those elevations were transient.

CONCLUSIONS

The prophylactic administration of ganciclovir after heart transplantation is safe, and in CMV-seropositive patients it reduces the incidence of CMV-induced illness.

Cardiac growth after pediatric heart transplantation

BACKGROUND

To assess whether normal cardiac growth occurs after heart transplantation in the pediatric age group, we performed a study of 13 infants and children who underwent orthotopic heart transplantation at Stanford.

METHODS AND RESULTS

The echocardiographic data from a population of 93 normal children were analyzed to determine estimates of the fifth, 25th, 50th, 75th, and 95th percentiles of the normal pediatric population. Growth curves for each of the cardiac dimensions were stratified into six classes representing each of the percentile bands, and dimensions for the 13 patients were tracked between early postoperative (early) and point of maximal follow-up (late). Results were compared by Student's paired t test to determine whether normal growth was occurring. The mean age at transplant was 5.0 +/- 1.3 years (mean +/- SEM) (range, 0.4-12.8 years), duration of follow-up was 3.1 +/- 0.4 years (1.3-5.8 years), and change in body surface area was 0.24 +/- 0.03 m2 (0.12-0.50 m2). Both right ventricular (RV) and left ventricular (LV) chamber dimensions were within the normal range at both early and late time points and grew normally as assessed by a lack of class changes. Early wall thickness measurements were above the 95th percentile in seven of 13 patients (LV), 12 of 13 patients (septum), and four of 13 patients (RV). Wall thickness measurements remained above normal, and there were no significant class changes at late follow-up. Histological examination in five patients showed markedly increased septal myocyte width, indicating myocyte hypertrophy. Atrial and great vessel anastomotic sites showed no evidence of obstruction by Doppler and catheterization studies.

CONCLUSIONS

These data demonstrate that normal cardiac chamber dimensional growth occurs at greater than 3 years' follow-up after pediatric heart transplantation. Significant LV and septal (and to a lesser extent RV) hypertrophy persists and may have implications for long-term allograft growth and function.

The "natural history" of the transplanted lung: rates of pulmonary functional change in long-term survivors of heart-lung transplantation

Long-term pulmonary function in HLT is well preserved with no evidence of functional decline as a result of transplant "aging," providing the allografts remain free of complications. Long-term survivors with OB appear to be able to maintain adequate oxygenation despite the marked alterations of pulmonary function. The ability to preserve gas exchange at reasonable levels of oxygenation may be the factors permitting extended survival with OB for mean periods of 36.0 months or greater. Preliminary studies suggest that a declining FEF50/FVC, at a time when pulmonary function is normal, may be an index of impending airway disease. Physiologically, from a long-term point of view, HLT remains a viable option for selected patients with end-stage cardiopulmonary disease.

Heart-lung and lung transplantation for cystic fibrosis

End-stage lung disease in Cystic Fibrosis (CF) now is considered to be one of the indications for heart-lung or double lung transplantation. Results of this surgery for 50 or so CF patients in the US and Europe are about the same as for other diseases, although there are some postoperative problems specific for this diagnosis. These include: need for higher oral dosages of cyclosporine, likelihood of precipitation of diabetes mellitus with high dosage corticosteroid therapy for acute lung rejection, constant threat of pathogens remaining in the sinuses, increased likelihood of drug toxicity to the liver and kidneys, and need to make a psychological transition from a patient with a fatal disease to one with optimism about the future. Although improved postoperative management likely will improve postoperative mortality and morbidity, scarcity of donor organs and the high cost of the procedure will limit the impact of this procedure on the general CF population.

Surgical management of doubly committed subarterial ventricular septal defects

The clinical presentation, diagnosis, and surgical treatment of 63 patients with doubly committed subarterial ventricular septal defects (DCVSD) were analyzed retrospectively. The patients were divided into three groups. Thirty-one patients had severe congestive heart failure in infancy and presently have a large ventricular septal defect that has no tendency to close or to produce aortic valve regurgitation (Group 1). Ideally, these defects should be closed in infancy, and the transpulmonary approach is recommended to achieve closure. In the first group, there was one death in a patient with a hypoplastic right ventricle. In Group 2, nineteen patients had aortic valve prolapse or aortic valve regurgitation. The DCVSD were moderately large or small. A number of DCVSD in Group 2 patients had maintained the normal offsetting of the arterial valves. These defects must be closed by the time mild aortic valve regurgitation has occurred. In Group 2, there was one late death in a patient who developed subacute bacterial endocarditis. The two patients who had severe aortic valve regurgitation required aortic valve replacement and underwent multiple surgical procedures to replace calcified bioprostheses. Group 3 comprised 13 patients who were diagnosed with tetralogy of Fallot. All of these patients had a large DCVSD with aortic valve overriding. All Group 3 patients survived radical repair of the defect, which required a transannular patch in most cases (76%).