Ebstein's Anomaly: "The One and a Half Ventricle Heart"

Tricuspid valve septal displacement cutoff value for mortality risk following biventricular repair in Ebstein anomaly

Background

Surgical intervention is the definitive treatment for Ebstein anomaly, offering both biventricular and nonbiventricular repair options. The objective of this study is to identify a specific cutoff value for tricuspid septal leaflet displacement, which will be a crucial factor in determining the selection of a surgical approach with lower mortality risk in biventricular repair.

Methods and Results

This is a retrospective cohort study of consecutive patients with Ebstein anomaly undergoing surgical intervention at the National Cardiovascular Center Harapan Kita from January 2010 to December 2023. A total of 83 patients with Ebstein anomaly were treated surgically; 43 of those underwent biventricular repair, whereas the remaining underwent nonbiventricular repair. Echocardiography was performed, and the Great Ormond Street Echocardiography score was calculated. Several risk factors were identified and stratified for patients with biventricular repair (n = 43). Tricuspid septal leaflet displacement was measured for each patient, and there was a statistically significant higher mortality risk directly proportional to higher displacement in patients with biventricular repair (P < 0.05). A cutoff value of 43.5 mm/m² for the tricuspid septal leaflet displacement is the best predictor of mortality risk in biventricular repair with 83.3% sensitivity and 93.3% specificity.

Conclusions

In patients with Ebstein anomaly undergoing a biventricular repair, mortality rates are significantly elevated in patients with a higher tricuspid septal leaflet displacement distance. The results of the study indicated that the mortality risk in biventricular repair can be predicted based on the tricuspid septal leaflet displacement distance using a cutoff value of 43.5 mm/m².

Ebstein's Anomaly: From Fetus to Adult-Literature Review and Pathway for Patient Care

Ebstein's anomaly, first described in 1866 by Dr William Ebstein, accounts for 0.3-0.5% of congenital heart defects and represents 40% of congenital tricuspid valve abnormalities. Ebstein's anomaly affects the development of the tricuspid valve with widely varying morphology and, therefore, clinical presentation. Associated congenital cardiac lesions tend to be found more often in younger patients and may even be the reason for presentation. Presentation can vary from the most extreme form in fetal life, to asymptomatic diagnosis late in adult life. The most symptomatic patients need intensive care support in the neonatal period. This article summarizes and analyzes the literature on Ebstein's anomaly and provides a framework for the investigation, management, and follow-up of these patients, whether they present via fetal detection or late in adult life. For each age group, the clinical presentation, required diagnostic investigations, natural history, and management are described. The surgical options available for patients with Ebstein's anomaly are detailed and analyzed, starting from the initial mono-leaflet repairs to the most recent cone repair and its modifications. The review also assesses the effects of pregnancy on the Ebstein's circulation, and vice versa, the effects of Ebstein's on pregnancy outcomes. Finally, two attached appendices are provided for a structured echocardiogram protocol and key information useful for comprehensive Multi-Disciplinary Team discussion.

The Use of Feature Tracking Technique for the Quantification of Ventricular Strain Pattern in Patients with Ebstein's Anomaly: A Case-Control Study

Background

Ebstein's anomaly (EA) is a congenital heart disorder characterized by abnormal function of the tricuspid valve. There are several ways to study tissue composition using magnetic resonance imaging (MRI). One of the most accurate methods is strain calculation using the feature tracking (FT) technique. Due to the novelty of the FT technique in cardiac magnetic resonance (CMR) imaging, there is a lack of comprehensive guidelines to conduct FT-MRI and to present a quantitative report. The current study is aimed to evaluate the FT technique in EA patients and to compare the obtained numerical values with those of healthy individuals.

Methods

A total of 33 individuals were enrolled in a study conducted in 2018-2019 at Shahid Rajaei Hospital, Tehran, Iran. Radial, longitudinal, and circumferential strain patterns of the left and right ventricles were determined in both the patients and the controls using the FT technique. Data were analyzed using SPSS software, version 22.0.

Results

The results showed a significantly lower left ventricular (LV) radial strain in EA patients compared to the control group (P=0.002). In addition, the right ventricular (RV) global longitudinal strain (GLS) in EA patients was significantly lower than in the controls (P=0.001). Other parameters (LV global longitudinal strain, RV radial strain, LV circumferential strain, and RV circumferential strain) did not differ significantly between the two groups.

Conclusion

Determination of strain patterns using cardiac MRI is a promising method for the diagnosis of EA. Markers such as LV longitudinal strain and RV-GLS are the most suitable parameters for the early diagnosis of heart dysfunction.

Surgical treatment of Ebstein anomaly in pediatric patients: A 10-year single-center study

OBJECTIVE

We report the early and long-term results of the strategies and surgical methods used in our center to treat pediatric patients who underwent surgical intervention to correct Ebstein anomaly (EA) in our center.

MATERIALS AND METHODS

In our study, a consecutive sample of 29 patients who underwent surgery for EA between February 2011 and February 2020 in our center were evaluated retrospectively.

RESULTS

The 29 patients underwent a total of 40 operations. Univentricular repair was performed in 5 (17.2%), 1.5 ventricular repair in 5 (17.2%), and biventricular repair in the remaining 19 (65.5%) patients. Cone reconstruction (CR) was performed in eight (27.5%), non-Cone tricuspid valve (TV) repair technique in five (17.2%), ring annuloplasty in two (6.9%), and TV replacement in two patients (6.9%) who had undergone biventricular repair. In two patients (6.9%), only close an atrial septal defect. Two (6.9%) patients underwent a second operation for advanced tricuspid regurgitation (TR) in the early period. None of the 15 patients who underwent CR and TV plasty had moderate or advanced TR before discharge. Early mortality was seen in 1 (3.4%) patient. The mean follow-up period of the patients was 48.4±27.6 months. Three (10.7%) of the patients who were discharged after their first operation later underwent a second operation for TV regurgitation in the long term. No mortality was observed in any patient during long-term follow-up.

CONCLUSION

Surgical treatment of EA is difficult, but its overall results are good. The anatomical repair rate is lower in neonatal and infant patients requiring surgery, but most of these patients underwent biventricular repair. Our long-term results demonstrated an acceptable survival rate, low mortality in the early postoperative period, and low incidence of re-intervention and morbidity.

Does addition of bi-directional cavo-pulmonary shunt to tricuspid repair in advanced cases of Ebstein anomaly result in better outcomes?

OBJECTIVES

Ebstein anomaly can be managed by single ventricular, bi-ventricular and one and a half ventricular repairs. We present midterm results of Comprehensive Tricuspid Valve repair (CTVR) with bi-directional cavo-pulmonary shunt (BCPS).

METHODS

In this prospective observational study (Jan2012-July2018), 69 patients underwent surgery for Ebstein anomaly. In Group I (n = 48; 69.6%), all patients got CTVR and a BCPS (one and a half ventricle repair). Group II (n = 15; 21.8%) consisted of a similar repair without BCPS (bi-ventricle repair). All patients were echocardiographed at six monthly intervals.

RESULTS

Median age of the cohort was 17 years (range 1-68). 12 (17.4%) patients were Carpentier type B, 51 (73.9%) were type C and 6 (8.7%) were type D. There were two early mortalities (2.89%). At a mean follow up of 3.2 ± 1.2 years, there were no late deaths and one delayed repair-failure in each group. Group I had significantly lower mean TR grade (1.2 ± 0.4vs1.6 ± 0.5, p = 0.03) as compared to Group II without a significant difference in the mean gradients (1.5 ± 0.5vs1.6 ± 0.6, p = 0.4). Mean indexed TAPSE (15.0 ± 6.7vs.16.6 ± 5.6 mm/m², p = 0.21), NYHA class (1.2 ± 0.4vs1.3 ± 0.4) and six-minute walk distance (506 vs 507 m, p = 0.7) was similar in both groups.

CONCLUSION

One and a half ventricle repair of Ebstein anomaly gives a more functionally competent, non-stenotic and durable tricuspid valve as compared to a two-ventricle repair. BCPS doesn't result in facial swelling or AV malformations. Preload reduction by BCPS may allow the myopathic ventricle to remodel.

Numerical Simulation of the Effect of Pulmonary Vascular Resistance on the Hemodynamics of Reoperation After Failure of One and a Half Ventricle Repair

OBJECTIVE

The one and a half ventricle repair (1.5VR) is a common clinical choice for patients with right heart dysfunction. Considering the influence of blood circulation failure and reoperation in urgent need, this essay aims to explore the hemodynamic effects of different pulmonary vascular resistance (PVR) values on reoperation after 1.5VR failure.

METHODS

The lumped parameter model (LPM) was used to simulate the reoperation, including the return biventricular repair (2VR), ligation of azygos vein (1.5VR') and return single ventricular repair (1.0VR). Firstly, the debugging parameters were used to simulate the hemodynamics of 2VR. Secondly, the value of PVR was changed from one to four times while the other parameters remained unchanged. Finally, 15 cardiac cycles were simulated and the 15th result was obtained. In this work, the left and right ventricular stroke work and their sum (Plv, Prv, Ptotal), the left and right ventricular ejection fraction (LVEF, RVEF), the mean Cardiac Output (mCO) and the mean pressure and flow-rate ratio of superior and inferior vena cava (mPsvc\mPivc and mQsvc\mQivc), respectively, were used to describe the hemodynamics of reoperation.

RESULTS

With the change of PVR from one to four times, the values of Plv, Prv, Ptotal, LVEF, and RVEF gradually decreased. The change rate of Plv, Ptotal and LVEF of 1.0VR were the largest in the three kinds of reoperation. The change rate of Prv of 1.5VR' was larger than that of 2VR, but it was the opposite for their EF change rate. The mCO of 2VR, 1.5VR', and 1.0VR decreased by 18.53%, 37.58%, and 48.07%, respectively. The mPsvc\mPivc of 1.5VR' increased from 3.76 to 6.77 and the mQsvc\mQivc decreased from 0.55 to 0.36, while the mPsvc\mPivc and mQsvc\mQivc of 2VR and 1.0VR remained 1 and 0.67, respectively. The peak value of the tricuspid flow-rate (Qti) waveform of 2VR and 1.5VR' changed from "E peak" to "A peak."

CONCLUSION

The numerical results demonstrate the highly reoperation-dependent hemodynamic consequences and their responses to variations in PVR. Comprehensive analysis of EF, mCO and ventricular stroke work indicates that PVR has a greater impact on 1.5VR' and 1.0VR. Therefore, we suggest that the selection strategy of reoperation should focus on PVR.

"RFEF" and mitral regurgitation jet direction: surrogate markers for likelihood of left ventricle reverse remodeling in patients with moderate chronic ischemic mitral regurgitation

Purpose

Surgical management of moderate chronic ischemic mitral regurgitation (CIMR) is controversial. We propose a simplified classification of moderate CIMR based on regurgitant fraction (RF), ejection fraction (EF), and jet direction (central/eccentric) to predict left ventricle (LV) remodeling and identify patient subsets which need mitral valve (MV) repair along with coronary artery bypass grafting (CABG).

Methods

In this prospective controlled study (n = 210), patients with moderate CIMR were randomized. Group I (n = 106) underwent off-pump CABG alone while group II (n = 104) underwent CABG + MV repair. The product of regurgitation fraction and ejection fraction ("RFEF") was taken as a surrogate for myocardial reserve. The cut-off defined was 0.12; patients with RFEF ≤ 0.12 were categorized as the "bad" and those with RFEF > 0.12 as the "good" subset. The patients were further subdivided on the basis of their mitral regurgitation (MR) jet direction (central/eccentric). The percentage improvement in left ventricular end-systolic volume index (LVESVI) and MR grade were recorded 6 monthly.

Results

Analysis of the continuous variable "RFEF" in conjunction with jet direction was performed. At 12 months, the patient in good subset with central direction of jet showed improvement in LVESVI % in both groups (p = 0.428), while the patients in bad subset with eccentric direction of jet showed significantly higher improvement in LVESVI %, group II as compared to group I (p = 0.004).

Conclusion

This study thus identifies "RFEF" as a surrogate for reverse remodeling capacity. In association with MR jet direction, predicts the subset of moderate CIMR patients most likely to have maximum LVESVI and MR grade reduction.