Endocardial Fibroelastosis Resection: When it Works and When it Does Not.

Endocardial fibroelastosis (EFE) is a thickening of the endocardial layer by accumulation of collagen and elastic fibers. Endothelial to mesenchymal transformation is proposed to be the underlying mechanism of formation. Although EFE can occur in both right and left ventricles, this article will focus on management of left ventricular EFE. Through its fibrous, nonelastic manifestation EFE restricts the myocardium leading to diastolic and systolic ventricular dysfunction and prevents ventricular growth in neonates and infants. The presence of EFE may be a marker for underlying myocardial fibrosis as well. The extent of EFE within the left ventricular cavity can be variable ranging from patchy to confluent distribution. Similarly the depth of penetration and degree of infiltration into myocardium can be variable. The management of EFE is controversial, although resection of EFE has been reported as part of the staged ventricular recruitment therapy. Following resection, EFE recurs and infiltrates the myocardium after primary resection. Herein we review the current experience with EFE resection.

Factors associated with morbidity, mortality, and hemodynamic failure after biventricular conversion in borderline hypoplastic left hearts.

OBJECTIVE: A subset of patients with borderline hypoplastic left heart may be candidates for single to biventricular conversion, but long-term morbidity and mortality persist. Prior studies have shown conflicting results regarding the association of preoperative diastolic dysfunction and outcome, and patient selection remains challenging. METHODS: Patients with borderline hypoplastic left heart undergoing biventricular conversion from 2005 to 2017 were included. Cox regression identified preoperative factors associated with a composite outcome of time to mortality, heart transplant, takedown to single ventricle circulation, or hemodynamic failure (defined as left ventricular end-diastolic pressure >20 mm Hg, mean pulmonary artery pressure >35 mm Hg, or pulmonary vascular resistance >6 international Woods units). RESULTS: Among 43 patients, 20 (46%) met the outcome, with a median time to outcome of 5.2 years. On univariate analysis, endocardial fibroelastosis, lower left ventricular end-diastolic volume/body surface area (when <50 mL/m2), lower left ventricular stroke volume/body surface area (when <32 mL/m2), and lower left:right ventricular stroke volume ratio (when <0.7) were associated with outcome; higher preoperative left ventricular end-diastolic pressure was not. Multivariable analysis demonstrated that endocardial fibroelastosis (hazard ratio, 5.1, 95% confidence interval, 1.5-22.7, P = .033) and left ventricular stroke volume/body surface area 28 mL/m2 or less (hazard ratio, 4.3, 95% confidence interval, 1.5-12.3, P = .006) were independently associated with a higher hazard of the outcome. Approximately all patients (86%) with endocardial fibroelastosis and left ventricular stroke volume/body surface area 28 mL/m2 or less met the outcome compared with 10% of those without endocardial fibroelastosis and with higher stroke volume/body surface area. CONCLUSIONS: History of endocardial fibroelastosis and smaller left ventricular stroke volume/body surface area are independent factors associated with adverse outcomes among patients with borderline hypoplastic left heart undergoing biventricular conversion. Normal preoperative left ventricular end-diastolic pressure is insufficient to reassure against diastolic dysfunction after biventricular conversion.

Infant Ross-Konno, Endocardial Fibroelastosis Resection and Mitral Valve Repair.

Optimal management of critical aortic stenosis (AS) in infants depends on the left ventricle's (LV's) ability to maintain adequate output. Determining feasibility of biventricular repair may be difficult, particularly in those with mitral disease, endocardial fibroelastosis (EFE), multi-level obstruction, and uncertain physiologic capacity. We report a case of a three-month-old with critical AS, severely reduced LV function, EFE, and moderate mitral regurgitation (MR), who underwent a Ross-Konno procedure with concomitant EFE resection and mitral valve repair. Although the technical sequence is challenging, definitive surgery completely relieved multi-level obstruction and MR with markedly improved LV function.

Left Ventricular Recruitment in Patients With Hypoplastic Left Heart Syndrome.

Hypoplastic left heart complex with "borderline left ventricle" and intact ventricular septum is a clinical conundrum for the congenital heart surgeon. The choice between neonatal biventricular repair and single ventricle palliation can be challenging, and the current tools to aid in the decision-making process fail to account for the morbidity associated with intermediate and late diastolic dysfunction. Staged ventricular recruitment, consisting of valvular repair techniques, resection of endocardial fibroelastosis, atrial septal restriction, and augmentation of pulmonary blood flow, has been shown to improve left ventricular size and function culminating in eventual biventricular circulation. Despite staged ventricular recruitment, some patients cannot undergo biventricular conversion. Strategies to address these complex patients, including the "reverse" double switch, are the next frontier in biventricular repair.

Combined Aortic and Mitral Annular Enlargement With Fibrous Skeleton Reconstruction.

In a pediatric population, congenital or acquired disease of the aortic and mitral valves may coexist and sometimes require replacement of both valves. Enlargement of aortic and mitral annuli may also be required. We demonstrate a challenging case that required upsizing of both prosthetic valves by redo anterior aortoventriculoplasty and patch enlargement of the aortic-mitral fibrous body. This case highlights the complexity and feasibility of enlarging both annuli in a reoperative setting, to implant larger prostheses.

Endocardial fibroelastosis in a dog with congestive heart failure.

In a 6-month-old, intact female, Japanese spitz presenting with severe dyspnea, lung ultrasonography revealed confluent B lines associated with severe echocardiographic left sided volume overload and systolic dysfunction. A congenital shunt or valvular dysplasia was not demonstrable. On electrocardiogram, there was a constant sinus rhythm, respectively sinus tachycardia. Cardiac troponin I was normal. Within 2 days of admission, the dog died of heart failure. On macroscopic postmortem examination, the left ventricle and atrium were markedly dilated, and the left ventricular endocardium had a mild diffuse whitish appearance. Histopathology revealed moderate to severe thickening of the left ventricular endocardium, composed mostly of abundant elastic fibers and fewer collagen fibers, diagnostic for endocardial fibroelastosis. In addition, there were mild degenerative changes of the atrioventricular valves. Endocardial fibroelastosis is a rare congenital disease and should be considered in a young dog if more common causes of echocardiographic dilated cardiomyopathy phenotype are ruled out.

Prognostic Value of Global Longitudinal Strain and Etiology After Surgery for Primary Mitral Regurgitation.

OBJECTIVES: This study sought to investigate whether left ventricular (LV) global longitudinal strain (GLS) is associated with long-term outcome after mitral valve (MV) surgery for primary mitral regurgitation (MR) and assess the differences in outcome according to MR etiology: Barlow's disease (BD), fibroelastic deficiency (FED), and forme fruste (FF). BACKGROUND: Appropriate timing of MV surgery for primary MR is still challenging and may differ according to the etiology. In these patients, LV-GLS has been proposed as more sensitive measure to detect subtle LV dysfunction as compared with LV ejection fraction. METHODS: Echocardiography was performed in 593 patients (64% men, age 65 ± 12 years) with severe primary MR who underwent MV surgery, including assessment of LV-GLS. The etiology (BD, FED, or FF) was defined based on surgical observation. During follow-up, primary endpoint was all-cause mortality and a secondary endpoint included cardiovascular death, heart failure hospitalizations, and cerebrovascular accidents. RESULTS: During a median follow-up of 6.4 (interquartile range: 3.6 to 10.4) years, 146 patients died (16 within 30 days after surgery), 46 patients were hospitalized for heart failure, and 13 patients had a cerebrovascular accident. Age (hazard ratio [HR]: 1.08; 95% confidence interval [CI]: 1.05 to 1.11; p < 0.001) and LV-GLS (HR: 1.13; 95% CI: 1.06 to 1.21; p < 0.001) were independently associated with all-cause mortality. Patients with LV-GLS >-20.6% (more impaired) showed significant worse survival than did patients with LV-GLS ≤-20.6%; of interest, patients with BD showed similar prognosis compared with FED and FF. In addition, previous atrial fibrillation (HR: 1.70; 95% CI: 1.01 to 2.86; p = 0.045) and LV-GLS (HR: 1.01; 95% CI: 1.01 to 1.15; p = 0.019) were independently associated with the secondary endpoint. CONCLUSIONS: LV-GLS is independently associated with all-cause mortality and cardiovascular events after MV surgery for primary MR and might be helpful to guide surgical timing. Importantly, patients with BD showed similar prognosis when corrected for age, compared with patients with FED or FF.

Flow disturbances and the development of endocardial fibroelastosis.

OBJECTIVES: Endothelial-to-mesenchymal transition (EndMT) has been identified as the underlying mechanism of endocardial fibroelastosis (EFE) formation. The purpose of this study was to determine whether hemodynamic alterations due to valvar defects promote EndMT and whether age-specific structural changes affect ventricular diastolic compliance despite extensive surgical resection of EFE tissue. MATERIAL AND METHODS: We analyzed EFE tissue from 24 patients with hypoplastic left heart syndrome (HLHS) who underwent left ventricular (LV) rehabilitation surgery at Boston Children's Hospital between December 2011 and March 2018. Six patients with flow disturbances across the aortic valve and/or mitral valve but no HLHS diagnosis and macroscopic appearance of "EFE-like tissue" in the LV were included for comparison. All samples were examined for amount of collagen/elastin production and degradation, and presence of active EndMT by histologic analysis. RESULTS: EFE tissue from patients with and without HLHS consisted predominantly of elastin and collagen fibers. There was no alteration in degradation activity for collagen or elastin as shown by in situ zymography. Active EndMT was found in all patients with and without HLHS with flow disturbances ("EFE-like"). In patients with HLHS, EFE infiltrated into the underlying myocardium with increasing age. CONCLUSIONS: Patients with and without HLHS with flow disturbances due to stenotic or incompetent valves develop EndMT-derived fibrotic tissue covering the LV. When EFE recurs, it is directly associated with flow disturbances and switches to an infiltrative growth pattern with increasing age, leading to increased diastolic stiffness of the LV.

Flow disturbances and progression of endocardial fibroelastosis - a case report.

Endocardial fibroelastosis (EFE) is described as thickening of the endocardium and is associated with hypoplastic left heart syndrome (HLHS). The stimulus for EFE and the mechanism for recurrence and/or progression need to be investigated. In this report, we describe the case of a 4-year-old HLHS patient who underwent several surgeries with EFE resections due to recurrence of EFE. EFE recurrence was associated with flow disturbances due to valvar defects. At her latest follow-up 7 months after the last surgery, competent valves and no EFE were identified on all imaging study.

Misdiagnosed anomalous left coronary artery from the pulmonary artery as endocardial fibroelastosis in infancy: A case series.

INTRODUCTION: Anomalous left coronary artery from the pulmonary artery (ALCAPA) is a rare but severe congenital cardiac malformation. The prognosis mainly depends on the early and accurate diagnosis and treatment. However, without a typical and specific clinical manifestation in early stage, ALCAPA has a higher rate of false initial diagnosis. DIAGNOSTIC AND THERAPEUTIC PROCEDURE: Three infants with impaired left ventricle (LV) function, LV enlargement, mitral valve regurgitation (MR), and LV endocardium thickness were initially diagnosed as endocardial fibroelastosis (EFE). Due to the treatment effectiveness with prednisone acetate and digoxin, abnormal Q waves with T inversion, and dilated right coronary artery (RCA), the diagnosis of ALCAPA was suspected. Lastly, cardiac angiography confirmed the diagnosis. All of them were transferred to the cardiac surgery department and received a successful surgical repair. The follow-up results showed that abnormal Q waves with T waves inversion on electrocardiogram gradually regressed and disappeared, LV ejection fraction and LV dilation returned to a normal range after surgery, with alleviation of MR. Besides, endocardial thickness secondary to ischemia also returned to normal. CONCLUSION: ALCAPA should be suspected when confronted with patients with left heart enlargement, impaired left ventricular function, and signs of myocardial ischemia, particularly in infancy. EFE is an important differential diagnosis and may also arise as a result of ALCAPA. Abnormal Q waves with T waves inversion, particularly in avL, dilated RCA and increased ratio of RCA/AO are important differential key points for the identification of ALCAPA and EFE. Awareness of this condition is essential for prompt recognition and referral to a tertiary cardiac center to enable early surgical intervention and improved prognosis for these children.

A case of cardioembolic stroke due to intracardiac papillary fibroelastoma evaluated by using transesophageal echocardiography.

A 62-year-old woman had a prior ischemic stroke in the right temporal lobe with dysarthria and dysesthesia of the left hand. Embolic stroke of undetermined source (ESUS) was diagnosed and warfarin was administered. However, transient ischemic attack recurred upon admission to our hospital. Paroxysmal atrial fibrillation and cerebral arterial stenotic lesions were absent. Transesophageal echocardiography revealed a mobile hyperechoic structure on the aortic valve indicating papillary fibroelastoma. She was diagnosed with a brain embolism due to the intracardiac tumor which was surgically excised and pathologically confirmed as papillary fibroelastoma. This type of tumor is relatively rare but it is important as an embolic source especially in ESUS. Transesophageal echocardiography was indispensable for detecting the embolic source in this patient with ESUS.

Surgical Treatment of Cardiac Tumors: Insights from an 18-Year Single-Center Analysis.

BACKGROUND The aim of this study was to investigate the clinical presentation, operative data, and early and late outcomes of a large patient cohort undergoing surgical treatment for cardiac tumors in our institution. MATERIAL AND METHODS A total of 181 patients underwent surgery because of suspected cardiac tumor in our institution between 1998 and 2016. In 162 cases, the diagnosis was confirmed postoperatively and these patients were included in this study. Preoperative baseline characteristics, operative data, and postoperative early and long-term outcomes were analyzed. RESULTS Mean age at presentation was 56.6±17.6 years, and 95 (58.6%) patients were female. There were 126 (77.8%) patients with benign cardiac tumors, while the remaining patients had malignant tumors (primary and metastasized). The mean follow-up time was 5.2±4.7 years. The most frequent histologically verified tumor type was myxoma (63%, n=102). In terms of malignant tumors, various types of sarcomas presented most primary malignant cardiac tumors (7.4%, n=12). The mean ICU length of stay was 1.7±2.2 days and overall in-hospital mortality was 3.1% (n=5). Frequent postoperative complications included mediastinal bleeding (5.8%, n=9), wound infection (1.3%, n=2), acute renal failure (5.6%, n=9), and major cerebrovascular events (n=7, 4.6%). The overall cumulative survival after cardiac tumor resection was 94% at 30 days, 85% at 1 year, 72% at 5 years, and 59% at 15 years. CONCLUSIONS Surgical treatment of cardiac tumors is a safe and highly effective strategy associated with good early and long-term outcomes.