Morbid anatomy in neonates with Ebstein's anomaly of the tricuspid valve: pathophysiologic and clinical implications

Impact of Neonatal Intervention on Left Ventricular Performance in Ebstein's Anomaly and Tricuspid Valve Dysplasia

BACKGROUND

Severe neonatal Ebstein's anomaly (EA) and tricuspid valve dysplasia (TVD) are associated with high perinatal morbidity and mortality. The authors recently demonstrated left ventricular (LV) dysfunction and dyssynchrony to be prevalent in affected newborns and to contribute to poor outcomes. The aim of this study was to investigate the impact of patent ductus arteriosus (PDA) closure, spontaneous or surgical ligation, or right ventricular exclusion (Starnes procedure) on LV performance in neonatal EA and TVD.

METHODS

Neonates with EA or TVD encountered from 2004 to 2018 at three institutions were identified. Pre- and postoperative LV function was assessed using two-dimensional, Doppler-derived deformation (six-segment vector velocity imaging) and two measures of mechanical dyssynchrony (the SD of time to peak and global dyssynchrony index), and values were compared using paired t test analysis or the Wilcoxon rank sum test.

RESULTS

Before the intervention, LV function was impaired in the PDA (n = 18) and Starnes (n = 6) groups and was similar between groups. After PDA closure, LV performance did not change. After the Starnes procedure, however, LV function, including synchrony, improved significantly: fractional area change from 45 ± 5% to 58 ± 8% (P = .003), global circumferential strain from -18.2 ± 5.0% to -32.5 ± 5.5% (P = .01), cardiac index from 1.9 ± 0.3 to 3.9 ± 1.5 L/min/m2 (P = .05), and circumferential strain dyssynchrony (dyssynchrony index from 0.19 ± 0.09 to 0.04 ± 0.02 [P = .009] and SD of time to peak from 59.8 ± 18.5 to 29.9 ± 8.2 [P = .02]).

CONCLUSION

The Starnes procedure results in early improvements in LV dysfunction and dyssynchrony, not observed after PDA closure in neonatal severe EA and TVD, which may benefit critically unwell neonates.

Left, but not right, ventricular status determines heart failure in adults with Ebstein anomaly - A case-control study based on magnetic resonance

BACKGROUND

Ebstein anomaly (EA) is a congenital heart defect affecting the right heart. Heart failure (HF) is a significant complication in adults with EA. It may result not only from the right ventricle (RV), but also from the left ventricle (LV) abnormalities. We evaluate the size and function of both ventricles in patients with EA in cardiac magnetic resonance (CMR); to assess their association with the clinical markers of HF.

METHODS

Study group: 37 unoperated adults with EA (mean age 43.0 ± 14.4y, 21[56.8%] males).

CONTROLS

25 volunteers (mean age 39.9 ± 10.9y, 15[60%] males). Study protocol included: CMR [ejection fraction (EF), end-diastolic (EDVind) and stroke volumes (SVind) indexed by body surface area]; cardiopulmonary test (peak VO2, %peak VO2, VE/VCO2 slope).

RESULTS

Size and systolic function of LV were reduced comparing to the controls [LVEDVind (ml/m2): 63.7(range 38.7-94.2) vs. 79.3(48.7-105.1), p < 0.001; LV SVind (ml/m2): 35.8(22.9-55.1) vs. 49.2(37.8-71.7), p < 0.0001; LVEF(%): 58.3(34-70.5) vs. 62.0(52.0-77.0), p = 0.009]. RV was enlarged comparing to the controls [RVEDVind (ml/m2): 124.3(52.8-378.9) vs. 83.0(64.0-102.0), p < 0.0001) with impaired systolic function (RV SVind (ml/m2): 22.7(11.1-74.1) vs. 48.0(37.8-71.7), p < 0.0001; RVEF(%): 38.0(21.0-66.1) vs. 59.0(49.0-69.0), p < 0.0001). A significant correlation was found between LVEDVind vs. peakVO2 (r = 0.52, p = 0.001); LV SVind vs. peakVO2 (r = 0.47,p = 0.005). There was no correlation between the right ventricular status and exercise capacity.

CONCLUSIONS

In adults with Ebstein anomaly the size of left ventricle is reduced, right ventricle is enlarged; the function of both is impaired. Abnormal exercise capacity is associated with left ventricular status. Ventricular interdependence probably plays a role in heart failure pathomechanism.

Narrative review of Ebstein's anomaly beyond childhood: Imaging, surgery, and future perspectives

Ebstein's anomaly is a rare congenital heart disease with malformation of the tricuspid valve and myopathy of the right ventricle. The septal and inferior leaflets adhere to the endocardium due to failure of delamination. This leads to apical displacement of their hinge points with a shift of the functional tricuspid valve annulus towards the right ventricular outflow tract with a possibly restrictive orifice. Frequently, a coaptation gap yields tricuspid valve regurgitation and over time the "atrialized" portion of the right ventricle may dilate. The highly variable anatomy determines the clinical presentation ranging from asymptomatic to very severe with need for early operation. Echocardiography and magnetic resonance imaging are the most important diagnostic modalities to assess the tricuspid valve as well as ventricular morphology and function. While medical management of asymptomatic patients can be effective for many years, surgical intervention is indicated before development of significant right ventricular dilatation or dysfunction. Onset of symptoms and arrhythmias are further indications for surgery. Modified cone reconstruction of the tricuspid valve is the state-of-the-art approach yielding the best results for most patients. Alternative procedures for select cases include tricuspid valve replacement and bidirectional cavopulmonary shunt depending on patient age and other individual characteristics. Long-term survival after surgery is favorable but rehospitalization and reoperation remain significant issues. Further studies are warranted to identify the optimal surgical strategy and timing before adverse right ventricular remodeling occurs. It is this article's objective to provide a comprehensive review of current literature and an overview on the management of Ebstein's Anomaly. It focuses on imaging, cardiac surgery, and outcome. Additionally, a brief insight into arrhythmias and their management is given. The "future perspectives" summarize open questions and fields of future research.

Ebstein Anomaly and Right Aortic Arch in Patient with Charge Syndrome

Ebstein anomaly is a rare congenital heart disease characterized by a varying degree of anatomical and functional abnormalities of tricuspid valve and right ventricle. It often coexists with other congenital cardiac malformations. Up to 79–89% of patients with Ebstein anomaly have interatrial communication in the form of patent oval foramen or atrial septal defect and more than one-third has other types of cardiac malformations. Association between Ebstein anomaly and right aortic arch is extremely rare and only few cases have been described in the literature so far. Much rarer than with other cardiac malformations, Ebstein anomaly is associated with non-cardiac malformations or genetic syndromes. Several cases of association between Ebstein anomaly and Charge syndrome have been reported, nevertheless, Ebstein anomaly accounts for less than 1% of cardiac defects seen in patients with Charge syndrome. In this case report, we present a unique case of a patient with Charge syndrome where both Ebstein anomaly and right aortic arch are present. The diagnosis of Ebstein anomaly and right aortic arch was established prenatally. In the first years of life, the patient did not exhibit any remarkable symptoms. However, over time, deterioration of right ventricle function and increased tricuspid regurgitation were observed, requiring consideration of surgical treatment at the age of five. In addition, delay in physical, motor, and mental development was observed and thus, at the age of five, the patient was consulted by a medical geneticist and a gene panel to test for structural heart defects was ordered. The test showed a mutation in chromodomain helicase DNA binding protein 7 (CHD7) gene, which, along with clinical features, allowed to establish a diagnosis of Charge syndrome. To the best of the authors’ knowledge, this is the first case report of a patient with Charge syndrome, Ebstein anomaly, and right aortic arch that has been described in the literature.

Myocardial Fibrosis in Pediatric Patients With Ebstein's Anomaly

BACKGROUND

Left ventricular dysfunction in Ebstein's anomaly (EA) is associated with higher mortality. The health of the left ventricular myocardium in children and adolescents with EA has not been investigated in detail.

METHODS

Patients with unrepaired EA who had undergone cardiac magnetic resonance imaging including T1 mapping were retrospectively reviewed. Patients were compared with age- and sex-matched controls. EA severity index was calculated using volumetric measurements at end diastole ([right atrial+atrialized right ventricular volumes]/[functional right ventricular+left atrial+left ventricular volumes]). Global circumferential and radial strain and as well as strain rate were examined using cardiac magnetic resonance feature tracking.

RESULTS

Twelve EA patients and an equal number of controls were included. Functional and atrialized right ventricular end-diastolic volumes were 84±15 and 21±13 mL/m², respectively. Late gadolinium enhancement, confined to the right ventricle, was found in 2 patients (16%). Left ventricular native T1 values and extracellular volume fractions were higher in patients compared with controls (1026±47 versus 956±40 ms, P=0.0004 and 28.5±3.4% versus 22.5±2.6%, P<0.001, respectively). Native T1 times correlated inversely with patients' age, body surface area, and O₂ saturations (r=-0.63, -0.62, and -0.91, respectively; P=0.02, P=0.02, and P<0.0001, respectively). EA severity index ranged between 0.15 and 0.94 and correlated with T1 values (r=0.76, P=0.003). Native T1 correlated with global circumferential strain (r=0.58, P=0.04) but not ejection fraction (EF). EA patients had reduced maximum oxygen uptake (Vo₂max). Vo₂max correlated inversely with T1 values (r=-0.79, P=0.01).

CONCLUSIONS

Children and adolescents with EA experience an abnormal degree of diffuse myocardial fibrosis. Its association with O₂ saturation points toward a role of hypoxemia in the pathogenesis of fibrosis. Larger and prospective studies are needed to evaluate the value of T1 mapping for risk stratification and monitoring in EA.

Trisomy 21 and Ebstein Anomaly: Diagnosis and Prognosis of a Rare Association

Trisomy 21 is considered the most common chromosomal aneuploidy, and congenital heart disease (CHD) is highly prevalent and relevant to the morbidity and mortality of these patients. Ebstein anomaly (EA) is a rare CHD characterized by tricuspid valve dysplasia with inferior septal leaflet displacement. Herein, we described a patient with trisomy 21 who presented with EA and discuss the association between the two conditions based on a literature review. We conclude that the concomitant occurrence of both conditions is considered to be rare. These individuals are most frequently diagnosed during birth and childhood, and they usually have a good prognosis, as observed with our patient and is typical for EA patients in general. However, it is important to be aware that electrophysiologic anomalies may also be present.

Quantitative Assessment of Left Ventricular Dysfunction in Fetal Ebstein's Anomaly and Tricuspid Valve Dysplasia

BACKGROUND

Fetal Ebstein's anomaly and tricuspid valve dysplasia (EA/TVD) are associated with high perinatal mortality relative to pulmonary atresia with intact ventricular septum (PAIVS), despite both requiring redistribution of the cardiac output (CO) to the left ventricle (LV). LV dysfunction is suspected to contribute to adverse outcomes in EA/TVD.

OBJECTIVE

We sought to examine global and segmental LV function in fetal EA/TVD with comparison to normal controls and PAIVS. We hypothesized that LV dysfunction in EA/TVD is associated with abnormal LV remodeling and interventricular mechanics.

METHODS

We retrospectively identified 63 cases of fetal EA/TVD (40 with retrograde ductal flow) and 22 cases of PAIVS encountered from 2004 to 2015 and compared findings to 77 controls of comparable gestational age. We measured the combined CO and global LV function using two-dimensional, Doppler-derived, deformational (six-segmental vector velocity imaging) and dyssynchrony indices (DIs; SD of time to peak), and a novel global DI.

RESULTS

EA/TVD fetuses demonstrated abnormal LV global systolic function with reduced ejection fraction, fractional area change, and CO, while in PAIVS we observed a normal ejection fraction, fractional area change, and CO. PAIVS, but not EA/TVD, demonstrated increased LV sphericity, suggestive of remodeling, and associated enhanced radial function in the third trimester. In contrast, while EA/TVD fetuses had normal LV segmental longitudinal strain, there was abnormal radial segmental deformation and LV dyssynchrony with increased SD of time to peak and DI.

CONCLUSIONS

Fetal EA/TVD is associated with a lack of spherical remodeling and presence of mechanical dyssynchrony, which likely contribute to reduced CO and ejection fraction. Clinical monitoring of LV function is warranted in fetal EA/TVD. Further studies incorporating quantification of LV function into prediction models for adverse outcomes are required.

Cardiac function and dysfunction in the fetus

Evaluation of fetal cardiac function is one of the most important components of fetal echocardiography. Fetal cardiac dysfunction is closely linked to risk of intrauterine fetal demise, in many, but not all cases is indicative of worse postnatal prognosis and may prompt the use of medications or interventions to optimize outcomes. There may be implications for termination versus continuation of pregnancy, an indication for early delivery, a change in location and even mode of delivery. In extreme cases, fetal cardiac dysfunction may prompt prenatal or early neonatal listing for cardiac transplantation. There are several important differences between the fetal and postnatal circulatory physiology which affect echocardiographic assessment of cardiac dysfunction. In this review, we examine the echocardiographic findings according to their underlying pathophysiology with reference to common causes.

Cardiovascular magnetic resonance evidence of myocardial fibrosis and its clinical significance in adolescent and adult patients with Ebstein's anomaly

BACKGROUND

Myocardial fibrosis is a common pathophysiological process that is related to ventricular remodeling in congenital heart disease. However, the presence, characteristics, and clinical significance of myocardial fibrosis in Ebstein's anomaly have not been fully investigated. This study aimed to evaluate myocardial fibrosis using cardiovascular magnetic resonance (CMR) late gadolinium enhancement (LGE) and T1 mapping techniques, and to explore the significance of myocardial fibrosis in adolescent and adult patients with Ebstein's anomaly.

METHODS

Forty-four consecutive patients with unrepaired Ebstein's anomaly (34.0 ± 16.2 years; 18 males), and an equal number of age- and gender-matched controls, were included. A comprehensive CMR protocol consisted of cine, LGE, and T1 mapping by modified Look-Locker inversion recovery (MOLLI) sequences were performed. Ventricular functional parameters, native T1, extracellular volume (ECV), and LGE were analyzed. Associations between myocardial fibrosis and disease severity, ventricular function, and NYHA classification were analyzed.

RESULTS

LGE was found in 10 (22.7%) patients. Typical LGE in Ebstein's anomaly was located in the endocardium of the septum within the right ventricle (RV). The LV ECV of Ebstein's anomaly were significantly higher than those of the controls (30.0 ± 3.8% vs. 25.3 ± 2.3%, P < 0.001). An increased ECV was found to be independent of the existence of LGE. Positive LGE or higher ECV (≥30%) was associated with larger fRV volume, aRV volume, increased disease severity, and worse NYHA functional class. In addition, ECV was significantly correlated with the LV ejection fraction (P <  0.001).

CONCLUSIONS

Both focal and diffuse myocardial fibrosis were observed in adolescent and adult patients with Ebstein's anomaly. Increased diffuse fibrosis is associated with worse LV function, increased Ebstein's severity, and worse clinical status.

Impact of Surgery in Ebstein's Anomaly Using Current Surgical Criteria

BACKGROUND

In Ebstein's anomaly (EA) current surgical criteria may not translate into better long-term survival. The aim of this study was therefore to determine if surgical treatment for EA increases survival, and to analyze factors associated with mortality.Methods and Results:A retrospective study was carried out involving 103 patients with surgical indication using current criteria, comparing operated (n=49; 47.5%) and non-operated patients (n=54; 52.4%); the severity of disease was similar in all cases. Overall follow-up was 12 years (range, 1-49 years). There were no differences in mortality: in the surgical and non-surgical groups, survival at 10 years was 92.8% vs. 90.7%; 20 years, 85.7% vs. 81.0%; and 30 years, 78.5% vs. 72.2%, respectively. On multivariate analysis right ventricular fractional shortening (RVFS) was associated with mortality in both groups. Decreasing RVFS was associated with worse survival according to severity: when RVFS was <20%, survival at 20, 40 and 60 years was 58%, 39%, and 12.5%, respectively (P<0.0013). Left ventricular ejection fraction also correlated with survival (P<0.0013).

CONCLUSIONS

Surgery did not translate into benefit in terms of survival, and this was clearly associated with RV function; therefore this should be a key factor in the surgical decision making.

Surgical Strategy Toward Biventricular Repair for Severe Ebstein Anomaly in Neonates and Infancy

BACKGROUND

Neonates with severe forms of Ebstein anomaly present a surgical challenge, and the Starnes operation as single ventricle palliation is highly advocated. Cone reconstruction for tricuspid valvuloplasty (TVP) has become a widely accepted technique, although very few cases of TVP have been reported in neonates. This report describes a surgical strategy for neonatal Ebstein anomaly, with an aim toward biventricular repair.

METHODS

Since 2007, 7 neonates or young infants with severe Ebstein anomalies have received TVP at the National Taiwan University Hospital, Taipei, Taiwan. The principle of cone reconstruction was applied with mobilization of all three leaflets and reattachment to the normal tricuspid annulus. The atrialized right ventricle was not plicated. In patients with pulmonary stenosis, the interatrial communication was not totally closed (n = 5), and a systemic-pulmonary shunt was added if needed (n = 3).

RESULTS

All patients presented with intractable heart failure or severe cyanosis requiring mechanical ventilation, or both. All patients had marked adherence of the anterior leaflet to the right ventricular free wall. Intracardiac anomalies including ventricular septal defect (n = 2) and tetralogy of Fallot (n = 1) were also repaired simultaneously. Six of the 7 patients (86%) survived. There were no late deaths or repeat TVPs for a median follow-up of 4.3 years (range, 0.8 to 9.9 years).

CONCLUSIONS

Reconstruction of the tricuspid valve is an acceptable surgical strategy in patients with severe neonatal Ebstein anomaly. Fenestrated atrial septal defect and systemic-pulmonary shunt can help overcome anatomic pulmonary stenosis and high pulmonary resistance in the neonatal period. This surgical strategy has a good survival outcome and preserves the possibility of complete biventricular repair.

Natural Course of Adult Ebstein Anomaly When Treated according to Current Recommendation

The objectives of this study were to assess the clinical outcomes of adults with Ebstein Anomaly (EA) according to their treatment modalities. All adult EA patients diagnosed between October 1994 and October 2014 were retrospectively evaluated by medical record review. Total 60 patients were categorized into 3 groups according to their treatment strategy, i.e. non-operative treatment (Group I, n = 23), immediate operative treatment (Group II, n = 27), and delayed operative treatment (Group III, n = 10). A composite of major adverse cardiac and cerebrovascular events (MACCE) and factors associated with MACCE were assessed in each treatment group. MACCE occurred in 13.0% patients in Group I, 55.6% patients in Group II and 50% in Group III (P = 0.006). Event free survivals at 5 years were 90% in Group I, 52.7% in Group II, 50.0% in Group III (P = 0.036). Post-operatively, most patients showed improvement on clinical symptoms. However, event free survival rate was lower in patients with operation compared to those with non-operative treatment (58.7% vs. 90.9%; P = 0.007). Major arrhythmic event occurred more frequently even after surgical ablation (50.0% vs. 20.0%; P = 0.034). Re-operation was more frequent in patients underwent delayed surgery compared to those with immediate surgery (50.0% vs. 18.5%; P = 0.001). Current guideline to decide patient's treatment strategy appeared to be appropriate in adult patients with EA. However, surgical ablation for arrhythmia was not enough so that concomitant medical treatment should be considered. Therefore, attentive risk stratification and cautious decision of treatment strategy by experienced cardiac surgeon are believed to improve clinical outcome.

Exercise performance in Ebstein's anomaly in the course of time - Deterioration in native patients and preserved function after tricuspid valve surgery

OBJECTIVE

The purpose of this study was to assess the longitudinal follow-up of exercise performance in patients with native Ebstein anomaly and patients who had received previous tricuspid valve surgery.

PATIENTS AND METHODS

We identified 59 patients with Ebstein anomaly who had performed at least two cardiopulmonary exercise tests within a minimum of 6months. 22 patients (15 female, 29.0±13.4years) with native conditions, 37 patients (21 female, 32.1±15.3years) had undergone surgery of their tricuspid valve before baseline testing.

RESULTS

In the non-operated group peak workload (2.58±0.7 to 2.38±0.7W/kg, p=.019) declined during a mean follow-up of 4.6±2.6years, whereas peak workload remained stable in the surgical group (2.02±0.6 to 2.06±0.7W/kg, p=.229) throughout the follow-up of 3.4±2.3years. In the 18 patients who had their surgery less than one year prior to the first CPET the exercise performance even increased during the follow-up. Peak blood pressure as a marker of cardiac adaption to exercise increased in the follow-up examination only in the surgical group (159±23 vs. 171±30mmHg, p=.007). In the non-operated group blood pressure remained unchanged at follow-up (161±26 vs. 166±29, p=.358).

CONCLUSION

Exercise performance deteriorates in non-operated patients with Ebstein anomaly in contrast to patients after tricuspid valve surgery where exercise performance remains stable. These facts promote a surgical intervention latest at the time when exercise performance decreases.

Preoperative Physiology, Imaging, and Management of Ebstein's Anomaly of the Tricuspid Valve

Ebstein's anomaly of the tricuspid valve (TV) refers to an embryological derangement of TV formation causing tethering of the septal and posterior leaflets of the valve to the underlying myocardium and apical displacement of the effective valve annulus, resulting in significant TV insufficiency and dilation of the right heart structures. The pathological abnormalities of the valve can vary significantly, resulting in a wide range of clinical presentations. Fetal diagnosis and neonatal presentations of the disease are typically the most severe and are associated with the highest mortality rates. Patients with less-severe disease will present later in life with symptoms of right heart failure and tachyarrhythmias. Medical and surgical management strategies are driven by the age at presentation, severity of disease, and any associated cardiac abnormalities. There are an increasing number of surgical options focused on valve repair.

Surgical management of symptomatic neonates with Ebstein's anomaly: choice of operation

OBJECTIVE

Symptomatic neonates with Ebstein's anomaly pose significant challenge. Within this cohort, neonates with associated anatomical pulmonary atresia have higher mortality. We review our experience with this difficult subset.

METHODS

A total of 32 consecutive symptomatic neonates with Ebstein's anomaly underwent surgical intervention between 1994 and 2013. Of them, 20 neonates (62%, 20/32) had associated pulmonary atresia. Patients' weights ranged from 1.9 to 3.4 kg. All patients without pulmonary atresia had two-ventricle repair. Of the 20 neonates, 16 (80%, 16/20) with Ebstein's anomaly and pulmonary atresia had two-ventricle repair and 4 had single-ventricle palliation, of which 2 underwent Starnes' palliation and 2 Blalock-Taussig shunts. Six recent patients with Ebstein's anomaly and pulmonary atresia had right ventricle to pulmonary artery valved conduit as part of their two-ventricle repair.

RESULTS

Overall early mortality was 28% (9/32). For those without pulmonary atresia, mortality was 8.3% (1/12). For the entire cohort of neonates with Ebstein's anomaly and pulmonary atresia, mortality was 40% (8/20; p=0.05). Mortality for neonates with Ebstein's anomaly and pulmonary atresia having two-ventricle repair was 44% (7/16). Mortality for neonates with Ebstein's anomaly and pulmonary atresia having two-ventricle repair utilising right ventricle to pulmonary artery conduit was 16% (1/6). For those having one-ventricle repair, the mortality was 25% (1/4).

CONCLUSIONS

Surgical management of neonates with Ebstein's anomaly remains challenging. For neonates with Ebstein's anomaly and anatomical pulmonary atresia, single-ventricle palliation is associated with lower early mortality compared with two-ventricle repair. This outcome advantage is negated by inclusion of right ventricle to pulmonary artery conduit as part of the two-ventricle repair.

Successful treatment of a rare case of neonatal Ebstein anomaly in a very low-birth-weight premature neonate

We report a successfully treated rare case of neonatal Ebstein anomaly in a low-birth-weight infant.

Fragmented QRS complex in adult patients with Ebstein anomaly and its association with arrhythmic risk and the severity of the anomaly

BACKGROUND

Fragmented QRS complex (fQRS) on 12-lead ECG, a marker of myocardial scar, is a predictor of arrhythmic events in patients with ischemic and nonischemic cardiomyopathy. We investigated whether the presence of fQRS is associated with the severity of the anomaly and with increased arrhythmic events in adult patients with Ebstein anomaly (EA).

METHODS AND RESULTS

In 51 consecutive adult patients with EA (median age, 37 years; 18 males), the severity index of EA calculated from echocardiographic data and clinical arrhythmic events were analyzed. The extent of fQRS in each patient was measured by counting the number of ECG leads showing fQRS. There were 35 (68.6%) patients with fQRS (fQRS group) and 16 (31.4%) patients without fQRS (non-fQRS group). fQRS was observed more frequently in the inferior (n=26) and precordial (n=25) leads versus the lateral leads (n=5). The patients in the fQRS group had a worse functional class, greater cardiothoracic ratios, more severe tricuspid regurgitation, larger atrialized right ventricular areas, higher EA severity scores, and more frequent arrhythmic events compared with those in the non-fQRS group. The atrialized right ventricular area showed a positive correlation with the fQRS extent (r=0.51; P<0.001). In multivariable Cox regression models, the presence of fQRS was independently associated with arrhythmic events (P=0.036).

CONCLUSIONS

Fragmented QRS on 12-lead ECG was associated with larger atrialized right ventricular area and an increased risk of arrhythmic events in adult patients with EA.

QRS duration and QRS fractionation on surface electrocardiogram are markers of right ventricular dysfunction and atrialization in patients with Ebstein anomaly

BACKGROUND

Ebstein anomaly is a rare and heterogeneous congenital heart defect affecting the tricuspid valve and right ventricular (RV) myocardium. Few studies have analysed the electrocardiographic features of Ebstein anomaly and none has addressed correlations with disease severity.

METHODS

Patients with Ebstein anomaly who had undergone electrocardiography and cardiac magnetic resonance (CMR) within 6 weeks between 2001 and 2009 were included. Exclusion criteria were: associated congenital cardiac defect, previous RV myoplasty and/or reduction surgery, class I anti-arrhythmic drug therapy, and paced/pre-excited QRS. Standard electrocardiogram (ECG) findings were correlated with CMR-based RV measures and clinical profile.

RESULTS

The mean age of the 63 study patients was 22 ± 13 years. An RV conduction delay (rsR' pattern in right precordial leads) was present in 45 patients (71%). The QRS duration correlated with anatomic RV diastolic volume (r = +0.56, P < 0.0001) and inversely with RV ejection fraction (EF; r = -0.62, P < 0.0001). The presence of QRS fractionation predicted greater atrialized RV volume (80 ± 31 vs. 45 ± 37 mL/m(2), P < 0.001). Normal QRS duration was associated with smaller anatomic RV diastolic volume (150 ± 57 vs. 256 ± 100 mL/m(2); P < 0.0001), higher RV EF (48 ± 6 vs. 34 ± 14%; P < 0.0001), higher oxygen consumption (VO(2)) at cardiopulmonary exercise (25.8 vs. 21.8 mL/kg/min, P = 0.05) and lower incidence of oxygen desaturation with exercise (25 vs. 65%, P = 0.02).

CONCLUSION

Delayed and prolonged depolarization of the RV is common in patients with Ebstein anomaly. The QRS duration is a marker of RV enlargement and dysfunction. QRS fractionation is associated with a greater atrialized RV volume. A preserved surface ECG identifies a subset of patients with Ebstein anomaly with mild morphological and functional abnormalities and better clinical profile.

Surgical Decision Making in Neonatal Ebstein’s Anomaly

Objective: There is currently no consensus of opinion regarding the optimal surgical management of Ebstein’s anomaly (EA) in neonates and young infants. Reported early mortality rates range from 25% to 100%. In this study, we present an algorithm for choosing the best management option for neonates with EA based on analysis of our experience. Patients and Methods: From 1994 to June, 2011, 48 neonates with a diagnosis of EA were managed by the same surgical team. Of these, two died before intervention; the remaining 46 either were managed medically initially (n = 20) or underwent surgical intervention during the neonatal period (n = 26) or early infancy (n = 9). Results: The mean weight was 3.6 ± 1.7 kg (1.9-8.6) and mean follow-up time was 6.3 ± 4.5 years (0.2-16). Of the 20 patients initially managed medically, 11 remain well without intervention and nine required complete repair in infancy, with 100% survival. Of the 26 neonatal operations, 23 (88%) were complete biventricular repairs, 1 Starnes’ palliation, and two Blalock–Taussig shunts (BTSs) ± pulmonary valvotomy. Among those having a two-ventricle repair, anatomic pulmonary atresia (APA) was a risk factor for early mortality (46.1%, 6 of 13) compared with those without pulmonary atresia (EA/no-PA; 10%, 1 of 10), P < .05. Conclusions: Most symptomatic neonates with EA will require early operation. For those with APA and mild tricuspid regurgitation (TR), a modified BTS and reduction atrioplasty may be the best initial option. For those with functional pulmonary atresia and severe TR and pulmonary regurgitation, ligation of the main pulmonary artery and placement of a BTS may provide the best initial palliation. For the rest, either a biventricular repair or a single-ventricle palliation is indicated.

Epicardial versus endocardial permanent pacing in adults with congenital heart disease

BACKGROUND

Permanent pacing (PM) in patients with congenital heart disease (CHD) presents unique challenges-with little known about the long-term outcomes.

METHODS

Pacemaker complications and reinterventions were reviewed over a 38-year period and were grouped by epicardial or endocardial approaches.

RESULTS

The average age at intervention was 37 ± 19 years for 106 patients and 259 PM procedures were performed (2.4 ± 2 per patient). From the first PM procedure, patients were followed for 11.6 ± 14 years. The most common indications for initial PM intervention were heart block (25%) and sinus node dysfunction (20%), yet reintervention was driven primarily by lead failure (49%). Endocardial systems were initially implanted in 73 patients (67%). Epicardial pacing was more common in patients with complex CHD (p = 0.006), cyanosis (p < 0.001), residual shunts (0.01), or Ebstein's anomaly (p = 0.01). Fifty-one devices (28%) developed lead or generator complications. Epicardial systems were most likely to develop lead failure (p < 0.0001), predominantly in the ventricular lead (p < 0.0001). Endocardial systems were found to be more durable than the epicardial systems (p = 0.023), and Ebstein's anomaly or an epicardial system was an independent predictor of lead failure.

CONCLUSIONS

Permanent pacing in CHD is associated with considerable morbidity and the need for repeat intervention, especially in those with Ebstein's anomaly. Epicardial pacing systems appear to have a higher incidence of lead failure and are significantly less durable in this group.

Effect of operation for Ebstein anomaly on left ventricular function

Our objective was to examine the outcomes of patients with left ventricular (LV) dysfunction who underwent operation for Ebstein anomaly. From April 1, 1972 to January 1, 2006, 539 patients with Ebstein anomaly underwent operation at Mayo Clinic. LV function was determined by echocardiography. Of the 495 patients with preoperative echocardiographic assessment of LV function, 50 had moderate or severe LV systolic dysfunction. In patients with LV dysfunction, the tricuspid valve (TV) was repaired in 12 patients and replaced in 36 patients; 1 patient had a 1.5 ventricle repair, and 1 patient had cardiac transplantation. There were 5 early deaths (10%). LV function improved in all but 4 patients after operation. In no patient did LV function worsen after operation. The 1-, 5-, and 10-year survival was 86%, 77%, and 67%, respectively. On univariate analysis, absence of sinus rhythm at dismissal (p = 0.003) was associated with greater overall mortality. For the entire cohort of 539 patients, LV dysfunction was independently predictive of late mortality (hazard ratio 3.76, p <0.001). At late follow-up (mean 6.9 years), 86% of patients were in New York Heart Association class I or II. In conclusion, LV systolic dysfunction occurs infrequently in patients with Ebstein anomaly and is a risk factor for increased late mortality. Although early mortality is greater in patients with LV dysfunction, the late results are favorable. Decreasing LV function should be an indication to promptly restore TV competence rather than a contraindication to TV operation.

Surgical correction of Ebstein anomaly: the Zurich approach

Ebstein's anomaly is a congenital defect primarily due to a failed-development of the tricuspid valve. The defect affects significantly surrounding structures (conducting tissue, right atrium and ventricle), which often need concomitant correction. We have extended our techniques for the repair of conventional atrio-ventricular valve insufficiency to this specific pathology. The video sequences show the repair of a severe form of Ebstein's anomaly with extensive mobilisation of the displaced leaflets and creation of a subvalvular apparatus with artificial chordae. Because of the absence of arrhythmia, the adjunction of ablation surgery to abnormal atrio-ventricular pathways was not necessary in this case and is not demonstrated in the videos.

Repair of Neonates and Young Infants With Ebstein’s Anomaly and Related Disorders

BACKGROUND

Severely symptomatic neonates and young infants with Ebstein's anomaly usually die without surgical intervention. The relative risks and benefits of single-ventricle palliation versus a two-ventricle repair are uncertain. In a recent series, 69% early survival with single-ventricle palliation was reported in 16 neonates with Ebstein's anomaly. Our institutional bias has been to do a two-ventricle repair in all such patients.

METHODS

We reviewed our entire surgical experience with a two-ventricle repair in the severely symptomatic neonate (n = 22) and young infant (n = 5). The indications for operation were ventilator dependence, severe cardiac failure, prostaglandin-dependent circulation, and gross cardiomegaly.

RESULTS

Between 1994 and 2006, 27 consecutive patients with Ebstein's anomaly underwent operation. Associated comorbidities included anatomic or functional pulmonary atresia (n = 18), ventricular septal defects (n = 3), small left ventricle (n = 3), hypoplastic branch pulmonary arteries (n = 3), previous cardiac surgery (n = 4), significant intracranial hemorrhage (n = 3), hepatic necrosis and renal insufficiency (n = 3), and malignant tachyarrhythmias (n = 4). Operations consisted of tricuspid valve repair (n = 23) or valve replacement (n = 2), Blalock-Taussig shunt only (n = 1), and bilateral pulmonary arterioplasty with bidirectional Glenn (n = 1). Hospital survival was 74%, and there have been no late deaths during a median follow-up period of 5.4 years (range, 0.2 to 12 years). Three patients required tricuspid valve replacement during the follow-up period. Late arrhythmia requiring medication is present in 1 patient. All patients are currently in New York Heart Association functional class I.

CONCLUSIONS

Two-ventricle repair currently has similar early survival compared with single-ventricle palliation. The advantages of a better physiologic repair can be anticipated for a longer follow-up period.

Adults with Ebstein's anomaly—Cardiopulmonary exercise testing and BNP levels

INTRODUCTION

Ebstein's anomaly is defined as the significant apical displacement of the part of the tricuspid valve causing significant tricuspid regurgitation and reduction of the functional right ventricle. The aim of the study was to evaluate exercise capacity with cardiopulmonary stress testing and to determine plasma BNP levels in adults with Ebstein's anomaly, and to establish their relation with echocardiogaphic grading of the lesion severity.

MATERIALS AND METHODS

Study group consisted of 21 patients (16 males, aged 40.3+/-11.5 years). The control group: 19 healthy individuals (13 males, aged mean 39.9+/-9.3 years). On echocardiography the grade of the lesion severity was calculated (EGE) and used to define the following four groups: I < 0.5, II: 0.5-0.9, III: 1.0-1.49, IV > 1.5. The forced vital capacity (FVC), first second forced expiratory volume (FEV1), peak oxygen uptake (peak VO2), and VE/VCO2 slope were assessed with cardiopulmonary stress test and plasma BNP levels measured with radioimmunometric assay.

RESULTS

In the studied group VO2 was lower than in control (21.9+/-5.4 vs. 33.6+/-8.3 mL/kg/min [p = 0.00001]), VE/VCO2 slope was higher in Ebstein's group (40.1+/-8.1, p = 0.00001). BNP levels were higher in the Ebstein group then in controls (35.9+/-25.0 vs. 17.2+/-9.9 pg/mL [p = 0.0002]) and did not differ significantly between EGE groups. PeakVO2 of 24.5+/-3.9 in patients from II EGE group were higher than in patients from EGE groups: III (17.2+/-5.2 p = 0.007) and IV (22.9+/-4.7 p = 0.05).

CONCLUSIONS

Exercise capacity of adults with Ebstein's anomaly is significantly reduced and plasma BNP levels are higher compared to healthy individuals. Exercise capacity in patients with Ebstein's anomaly becomes gradually lower alongside the EGE severity; however, BNP levels do not correlate significantly with this parameter.

Relation of limiting ductal patency to survival in neonatal Ebstein's anomaly

Fetal and neonatal Ebstein's anomaly has a poor prognosis, and there are few contemporary reviews of management and outcomes. This study retrospectively reviewed a management algorithm promoting early ductal closure after anatomic pulmonary obstruction had been excluded or relieved in neonatal Ebstein's anomaly from 1995 to 2004. Twenty-eight patients with Ebstein's anomaly were identified, 9 prenatally (8 with hydrops) and 19 postnatally, at a median age of <24 hours. Celermajer index scores predicted a mortality rate of 35%. Prostaglandins were administered to 24 of 28 patients. Prostaglandins were continued for obstructive lesions in 9 until the relief of pulmonary outflow obstructions or aortic coarctation repair. In 8 of 9 patients, prostaglandins were discontinued after intervention. One patient continued receiving prostaglandins until a Blalock-Taussig shunt was performed 3 weeks after surgical valvotomy. Prostaglandins were discontinued in 17 of 24 patients with uneventful ductal constrictions. The ductus arteriosus persisted in 5 patients with hemodynamic instability, of whom 4 underwent ductal ligation, with immediate improvement. In 1 of 24 patients, unrecognized right ventricular outflow tract obstructions became apparent when prostaglandins were discontinued. Prostaglandins were restarted until a primary superior cavopulmonary anastomosis was performed at 7 weeks. The median follow-up period of 26 survivors was 34 months (range 3 to 106), 4 after bidirectional superior cavopulmonary anastomoses and 1 after a Fontan procedure. In conclusion, in neonatal Ebstein's anomaly of the tricuspid valve, prolonged patency of the ductus arteriosus in patients without anatomic outflow tract obstructions is deleterious. "Circular shunts" may develop in patients with pulmonary and tricuspid insufficiency. The ligation or spontaneous constriction of the ductus arteriosus may result in hemodynamic improvement. This approach to neonatal Ebstein's anomaly of the tricuspid valve has yielded a substantial reduction in mortality to 7% in a high-risk cohort.

Color Doppler flow pattern in antenatal diagnosis of unguarded tricuspid valve

We describe an antenatally diagnosed case of unguarded tricuspid valve in a 15-week fetus. Because of its rarity, the differentiation of this anomaly from other tricuspid valve dysplasias is difficult. Tricuspid regurgitation is the hallmark of Ebstein's anomaly and other tricuspid valve abnormalities, whereas in unguarded tricuspid orifice there is total absence of the valve, resulting in 'to and fro' flow across the right-sided chambers. The color Doppler flow pattern helps in differentiating this anomaly from others. The antenatal diagnosis was confirmed on autopsy.

Left heart lesions in patients with Ebstein anomaly

OBJECTIVE

To identify the incidence of left heart abnormalities in patients with Ebstein anomaly, recognizing that left-sided lesions in this patient group have been overlooked.

PATIENTS AND METHODS

According to the echocardiography database at the Mayo Clinic in Rochester, Minn, 106 consecutive patients with Ebstein anomaly underwent echocardiography between July 1, 2001, and February 28, 2003. Clinical data as well as electrocardiographic and echocardiographic reports and images were reviewed.

RESULTS

Ebstein anomaly was severe in 76 patients (72%). Previous tricuspid valve surgery was reported in 46 patients (43%), and previous closure of an atrial septal defect or patent foramen ovale was reported in 34 patients (32%). Left ventricular (LV) myocardial changes resembling noncompaction occurred in 19 patients (17.9%), LV systolic dysfunction in 7 patients (7%), LV diastolic dysfunction in 34 (36%) of 95 patients, and LV dilatation in 4 patients (4%). Additional left-sided cardiac lesions included mitral valve prolapse in 16 patients (15%), bicuspid aortic valve in 8 (8%), mitral valve dysplasia in 4 (4%), and ventricular septal defect in 8 (8%). Wolff-Parkinson-White syndrome occurred in 22 patients (21%). The QRS axis tended to be different in LV noncompaction with a mean +/- SD axis of 12 degrees +/- 74 degrees vs 36 degrees +/- 66 degrees overall (P=.08). Otherwise, there were no differences in clinical or surgical data between the groups with normal and abnormal LV myocardium.

CONCLUSIONS

In patients with Ebstein anomaly, left heart abnormalities involving the myocardium or valves were observed in 39% of patients. Ebstein anomaly should not be regarded as a disease confined to the right side of the heart.

Noncompacted myocardium in ebstein's anomaly: initial description in three patients

Exercise intolerance in Ebstein's anomaly is usually attributed to desaturation secondary to right-to-left shunting as a result of a small or distorted left ventricle (LV), significant tricuspid valve regurgitation, right ventricular dysfunction, or a combination of these. We observed one boy (age 15 years) and two women (ages 20 and 29 years) with severe Ebstein's anomaly and strikingly abnormal LV myocardium resembling the features described for LV noncompaction. LV size and systolic function were normal in the two women; the boy had a dilated LV with severely diminished ejection fraction. The LV myocardium was found to be unusually coarse and hypertrabeculated, with small intertrabecular recesses and an irregular endocardial surface. The findings in these 3 patients represent the whole spectrum of mild to severe LV noncompaction. Diastolic dysfunction was present in 2 of the 3 patients. Exercise tolerance was diminished in all. There was no mitral or aortic valve disease. The 15-year-old boy underwent heart transplantation 6 months later for biventricular failure. Thus, Ebstein's anomaly does not seem to be a pathology confined to the right ventricle, but may rarely lead to LV noncompacted myocardium. This LV pathology may be an additional explanation for exercise intolerance or signs of left heart failure in patients with Ebstein's anomaly.

The clinical profile of Ebstein's malformation as seen from the fetus to the adult in 52 patients

Ebstein's malformation of the tricuspid valve is a rare but complex congenital cardiac lesion characterised by a variable degree of dysplasia and displacement of the proximal attachments of its inferior and septal leaflets from the true atrioventricular junction. The aim of our retrospective study is to report the risk factors for mortality, and to determine the clinical profile as seen in 52 cases diagnosed in our service between 1978 and 2002, concentrating in particular on the outcome for the neonatal patient. There were 26 females and 26 males, and the age at presentation ranged from 30 weeks gestational age to 46 years. We found 23 associated cardiac anomalies in 20 cases. Of the patients, 11 patients (21%) died. Actuarial survival at 30 years was 65%. Predictors of death included fetal or neonatal presentation, presence of associated defects, a grade within the Celermajer index of 3 or 4, and a cardiothoracic ratio equal to or greater than 65%. The diagnosis was made in the neonatal period in 24 patients, nine of whom died. Of the 15 survivors, only 4 are free of symptoms. Surgical treatment was undertaken in 9 patients, with a mortality rate of 33% without late deaths, with all the survivors being in good condition. The mean period of follow-up for the 41 living patients was 16.5 years. An arrhythmia of variable severity appeared during the evolution of 27 patients (66%). At present, only 7 cases are in the functional class III or IV of the grading system of the New York Heart Association, but 25 patients (61%) needed some medical treatment, meanly for arrhythmic events. Thus, fetal and neonatal presentation of Ebstein's malformation is associated with a poor outcome. Moreover, the echocardiographic appearance, marked cardiomegaly, and the presence of associated lesions are all risk factors for mortality. Arrhythmia and need of medical treatment are common in older children and adults. Survival after surgical treatment is associated with a good outcome.

Ebstein Anomaly Associated With Unusual Conduction Delay and Sick Sinus Syndrome-A Case Report-

A 64-year-old man was admitted to our hospital because of palpitation, dyspnea on effort, and facial edema. The echocardiographic diagnosis was Ebstein anomaly. Although the 12-lead electrocardiogram showed an atrial rate of 150 beats/min and no typical flutter wave, the electrophysiological study showed counterclockwise rotation of excitation along the tricuspid annulus. Because of sinus arrest and syncope, a permanent pacemaker was implanted, but the right atrium was not captured by electrical stimulation at 5 V/0.4 ms, except for the orifice of coronary sinus, and the intracardiac P wave was only 0.2 mV or less. This is a rare case of Ebstein anomaly characterized by unusually prolonged conduction in the atrium, the basis of which was global myocardial damage, including the ventricles.

The normal offset of the tricuspid septal leaflet in the fetus

OBJECTIVE

To quantify the normal distance between the insertion of the medial leaflets of the mitral valve and tricuspid valve in the fetal heart. This mitral valve-tricuspid valve distance was compared with the distance from known cases of Ebstein anomaly.

METHODS

An apical 4-chamber view was obtained at end diastole in fetuses between 18 and 41 weeks' gestation. Calipers were placed parallel to the ventricular septum, with 1 caliper on the medial insertion of the mitral valve and a second caliper on the medial insertion of the tricuspid valve. The distance recorded was plotted against gestational age. Statistical analysis was performed by descriptive and linear regression techniques.

RESULTS

One hundred forty-five fetuses were studied. The mean +/- SD mitral valve-tricuspid valve distance in the second trimester was 2.8 +/- 0.9 mm with a range of 1.2 to 5.0 mm; in the third trimester it was 4.6 +/- 1.1 mm with a range of 2.2 to 6.9 mm. Regression analysis showed that with each 1-week increase in gestational age, there was an increase of 0.15 mm in separation between the medial leaflets of the mitral valve and tricuspid valve (beta = 0.15 +/- 0.011).

CONCLUSIONS

A positive correlation between mitral valve-tricuspid valve distance and advancing gestational age was found. The reference range described allows for the identification of a fetal heart with normal variation in the mitral valve-tricuspid valve distance. Further downward displacement of the medial tricuspid cusp suggests the possibility of Ebstein anomaly.

Ebstein's anomaly of the tricuspid valve complexities and strategies

Ebstein's anomaly of the tricuspid valve is a fascinating but very complex congenital malformation with a wide spectrum of anatomic and clinical variations. A brief review is given of the clinical presentation and therapeutic options. We need further functional studies to understand the relationship between clinical severity and anatomic derangement. This will lead to better decision-making regarding the indications for and timing of surgery, which are still problematic.

Repair of Ebstein's anomaly in the symptomatic neonate: an evolution of technique with 7-year follow-up

BACKGROUND

Ebstein's anomaly in the severely symptomatic neonate is usually fatal. Until recently, successful repair has not been reported and various palliative operations have been associated with prohibitive mortality. Recently, we published our initial results with biventricular repair in 3 severely symptomatic neonates. We now update our experience with emphasis on the evolution of our surgical technique and the medium-term follow-up of these patients.

METHODS

Since 1994, 8 severely symptomatic neonates and young infants underwent biventricular repair by one surgeon. Six had Ebstein's anomaly and 2 had physiologically similar pathology with severe tricuspid valve dysplasia, cyanosis, and gross cardiomegaly. One Ebstein patient (2 months old) had undergone a Starnes operation elsewhere. Weight of the patients at operation ranged from 2.1 to 6.4 kg (mean 2.7 kg). Five patients had either anatomical (n = 3) or functional (n = 2) pulmonary atresia. Severe (4/4) tricuspid regurgitation was present in all except 1 (Starnes operation), and cardiothoracic ratio exceeded 0.85 in all patients. Echocardiography severity scores were >1.5 in 6 (grade 4/4) and 1.3 in 1 (grade 3/4). Repair consisted of tricuspid valve repair, reduction atrioplasty, relief of right ventricular outflow tract obstruction, partial closure of atrial septal defect, and correction of all associated cardiac defects. Technique of tricuspid valve repair evolved over time: 3 had Danielson-type repairs, 3 had DeVega-type repairs, and 2 had complex repairs.

RESULTS

One patient died in hospital: a 2.1 kg patient with tricuspid dysplasia, anatomical pulmonary atresia, and hypoplastic pulmonary arteries. The other 7 patients are all in functional class I and in sinus rhythm. Although 3 patients had symptomatic tachyarrhythmias before surgery, no child has experienced SVT after discharge. At recent echocardiography 4 patients had mild tricuspid regurgitation, and 2 had mild-moderate (2/4) tricuspid regurgitation. Three patients are now 7 years old, 2 are almost 2 years old, and the remaining 2 patients are 1 year old.

CONCLUSIONS

Surgical repair of the severely symptomatic neonate with Ebstein's anomaly is feasible and safe. The repair appears durable and with good medium-term outcome.

Total right ventricular exclusion procedure: an operation for isolated congestive right ventricular failure

OBJECTIVE

To prevent possible deleterious effects of right ventricular volume overload on cardiorespiratory function, we developed a total right ventricular exclusion procedure for the treatment of end-stage isolated congestive right ventricular failure.

METHODS

Since 1996, this procedure has been performed in 5 patients in New York Heart Association functional class IV: 2 adults with arrhythmogenic right ventricular dysplasia and 3 children with Ebstein anomaly. The entire right ventricular free wall was resected along the atrioventricular groove and then parallel to the interventricular septum, sparing the pulmonary valve and a skeletonized right coronary artery. The orifice of the tricuspid valve was closed with either a polytetrafluoroethylene patch or with its leaflets. The defect of the right ventricular free wall was covered with a polytetrafluoroethylene patch in the 2 patients with arrhythmogenic right ventricular dysplasia and directly closed with the remnant of the free wall in the 3 children with Ebstein anomaly. After resection of a redundant right atrial wall, coronary sinus blood flow was rerouted into the left atrium through an atrial septal defect. A total cavopulmonary connection was constructed in 4 patients and a bidirectional superior cavopulmonary anastomosis in 1 infant. The heart was controlled with a DDD pacemaker in 3 patients.

RESULTS

The patients were extubated at a mean of 14 hours postoperatively (range, 1-38 hours). There were no early or late deaths. At follow-up, ranging from 8 to 57 months, the mean cardiothoracic ratio had decreased from 74% +/- 7% before the operation to 52% +/- 6% (P <.01). All patients are in functional class I. Neither of the patients with arrhythmogenic right ventricular dysplasia have had attacks of ventricular tachycardia nor are they using antiarrhythmic medication.

CONCLUSIONS

The total right ventricular exclusion procedure provides effective decompression of the lung, as well as the left ventricle, and may result in more effective volume loading of a surgically created single ventricle with increased systemic output. We believe that this new surgical option offers rescue treatment for isolated end-stage right ventricular failure in critically ill patients.

Absent pulmonary valve with tricuspid atresia or severe tricuspid stenosis: report of three cases and review of the literature

Absence of the pulmonary valve occurs usually in association with tetralogy of Fallot and occasionally with an atrial septal defect or as an isolated lesion. Very rarely it occurs with tricuspid atresia, intact ventricular septum, and dysplasia of the right ventricular free wall and of the ventricular septum. We present the clinical, anatomic, and histologic findings of a new case, and for the first time, the data from two patients with absent pulmonary valve and severe tricuspid stenosis, who exhibited similar histologic findings. We also reviewed the clinical and anatomic data of 24 previously published cases and compared them with the new cases. In all three new cases, the myocardium of the right ventricle was very abnormal. In the two cases with tricuspid stenosis, large segments of myocardium were replaced with sinusoids and fibrous tissue. In the case with tricuspid atresia, the right ventricular free wall contained only fibroelastic tissue. The ventricular septum in all three patients showed asymmetric hypertrophy and in two of the three patients, multiple sinusoids had replaced large segments of myocardial cells. The left ventricular free wall myocardium and the walls of the great arteries were unremarkable. Our data indicate that myocardial depletion involving the right ventricular free wall and the ventricular septum and its replacement by sinusoids and fibroelastic tissue occur not only in cases of absent pulmonary valve with tricuspid atresia but also in cases of absent pulmonary valve with tricuspid stenosis. The degree of myocardial depletion varies and is more severe when the tricuspid valve is atretic.