A Novel Method for Quantification of Left Ventricular Noncompaction Using Two-Dimensional Echocardiography in Children

Objective

Although there are several echocardiographic criteria, there is not yet a general consensus about the diagnosis of left ventricular noncompaction. The current criteria are mostly based on the areas with maximal noncompaction in the heart. The echocardiographer may miss this maximal point leading to a misdiagnosis. Accordingly, we suggested a new method to measure the percentage of myocardial noncompaction using two-dimensional echocardiography.

Methods

In this study, the new method was examined on 4 noncompaction and 26 dilated cardiomyopathies, and 25 normal subjects. The percentage of noncompaction was measured at 3 levels (apical, papillary muscle and mitral valve) and averaged.

Findings

The mean percentages of myocardial noncompaction were 3.59±2.27, 8.86±5.52 and 34.7±26.1 in the control, dilated cardiomyopathy and noncompaction groups, respectively. A value of 17% or greater could distinguish left ventricular noncompaction from dilated cardiomyopathy with 92% specificity and 100% sensitivity and from normal subjects with 100% specificity and sensitivity. This percentage had a statistically significant association with noncompacted to compacted myocardial thickness ratio (P<0.001).

Conclusion

This method showed good correlations with the existing echocardiographic and magnetic resonance criteria. However, it is not dependent on finding the area of maximal involvement. Being comparable to magnetic resonance imaging in accuracy, it is easier to perform and more available.     

Anomalous Left Coronary Artery from the Right Sinus of Valsalva and Noncompaction of the Left Ventricle

Anomalous origin of the left coronary artery is a well-known cause of sudden death. Noncompaction of the ventricular myocardium is a cardiomyopathy characterized by prominent trabeculae and deep intertrabecular recesses. Both anomalies are rare. We report the case of a child with both anomalous origin of the left coronary artery from the right sinus of Valsalva and noncompaction of the left ventricular myocardium found during an evaluation for Kawasaki’s disease.     

Myocardial growth before and after birth: clinical implications

Perinatal changes in myocardial growth have recently evoked considerable interest with regard to cardiac chamber development with congenital cardiac lesions and to myocardial development in preterm infants. It is suggested that cardiac chamber development is influenced by blood flow. Experimental pulmonary stenosis in fetal lambs may induce either greatly reduced or markedly increased right ventricular volume. Ventricular enlargement appears to be associated with a large ventricular volume load resulting from tricuspid valve regurgitation. A small competent tricuspid valve is associated with reduced flow through the ventricle due to outflow obstruction and a small right ventricle. Postnatal growth of the ventricles in congenital heart disease is discussed. Increase in myocardial mass prenatally is achieved by hyperplasia, both during normal development and when myocardial mass is increased by right ventricular outflow obstruction. Postnatally, increases in myocardial mass with normal growth, as well as with ventricular outflow obstruction, are largely due to hypertrophy of myocytes. Myocardial capillary numbers do not increase in proportion with myocyte numbers in ventricular myocardium in association with outflow obstruction. The postnatal effects of these changes in congenital heart lesions are considered. Studies in fetal lambs suggest that the late gestational increase in blood cortisol concentrations is responsible for the change in the pattern of myocardial growth after birth. The concern is raised that prenatal exposure of the premature infant to glucocorticoids, administered to the mother to attempt to prevent hyaline membrane disease in the infant, may inhibit myocyte proliferation and result in a heart with fewer than normal myocytes. This would necessitate that each myocyte would have to hypertrophy abnormally to achieve a normal cardiac mass postnatally.     

心肌致密化不全合并弥漫性冠状动脉右室瘘1例

目的：探讨心肌致密化不全合并弥漫性冠状动脉瘘的临床特点及诊断方法。方法：报告1例心肌致密化不全合并弥漫性冠状动脉右室瘘患儿,回顾其临床症状、辅助检查结果和治疗方案。在国外数据库（Pubmed、OVID和Elsevier）和国内数据库（万方和维普）中检索心肌致密化不全合并冠状动脉瘘和心肌病合并冠状动脉瘘病例的文献,检索时间为建库至2017年3月30日。总结此类病例的临床表现、诊断和治疗。结果：本文患儿为6月龄女婴,因“胃纳差伴盗汗2周”于2013年10月12日在上海交通大学医学院附属上海儿童医学中心心内科就诊。二维超声心动图显示,左心室增大伴左室致密化不全、左右冠状动脉扩张、右心室内心肌窦状间隙持续状态、二尖瓣中度返流、心室收缩功能低下等。心导管造影及冠状动脉造影检查显示,右冠状动脉及左前降支弥漫性微小右心室瘘、二尖瓣返流、左心室增大。予地高辛、速尿、安体舒通后患儿症状稍好转。国外数据库中检索到2例心肌致密化不全合并冠状动脉左室瘘的成年病例,以进行性呼吸困难和心前区疼痛为主要临床表现,心肌缺血表现更明显,诊断主要依靠二维超声心动图及心导管造影和冠状动脉造影检查,缺乏有效治疗手段;有部分心肌病合并心肌致密化不全患者接受选择性冠状动脉瘘介入封堵术的尝试。结论：心肌致密化不全合并冠状动脉瘘是一类罕见的先天性心脏发育异常疾病,婴儿临床症状主要为纳差、盗汗等心功能不全的表现,确诊主要依靠二维超声心动图以及心导管造影、冠脉造影检查,目前尚缺乏有效治疗手段,以强心、利尿、扩血管改善心功能治疗为主。     

Noncompaction of the right ventricle following Senning repair

A three-year-old boy presented with generalized edema, respiratory distress, prominent right ventricular impulse and hepatosplenomegaly. He had undergone Senning repair at one year of age. On his echocardiography, there were numerous prominent trabeculations and deep intertrabecular recesses measuring approximately 5 mm in depth along the free wall and right ventricular apex. Echogenicity of the endocardial surface was increased suggesting a fibrotic process in progress. Intertrabecular recesses were observed to be filling from the ventricle by color Doppler which is consistent with noncompaction. Various semilunar valve obstructions were shown to be responsible for the persistence of deep endomyocardial spaces surrounded by exeggerated hypertrophy of the trabeculae. This report presents the echocardiographic findings of right ventricular cardiomyopathy associated with dextroposition of the great arteries following Senning operation resembling noncompaction. Thus, this rare entity needs to be clarified regarding morphological criteria in distinction from other cardiomyopathies.     

Isolated abnormality ("noncompaction") of the myocardium in 3 children]

In three asymptomatic children an isolated myocardial noncompaction was detected by echocardiography at age 11 months, 5 weeks and 5.5 years. In the first male infant both ventricles and septum were severely affected and myocardial function was depressed. Nevertheless, during a follow up of 16 months he remained asymptomatic on anticongestive therapy. In the other two children apex and lateral wall of the left ventricle were affected and myocardial function was still normal. The second boy had also an infantile epilepsy-encephalopathy syndrome and the third child (a girl) had a Wolff-Parkinson-White syndrome; an association of either syndromes with myocardial noncompaction has not been reported earlier. DISCUSSION: Myocardial noncompaction (spongy myocardium) is a rare maldevelopment, which occurs either associated with certain congenital heart defects or, even more rarely, isolated, as the two cases reported here. Myocardial failure, severe arrhythmias or thromboembolism may occur at any age and determine the outcome. Clinical course, therapy and prognosis are similar to dilatative cardiomyopathy, which represents an important differential diagnosis.     

Fetal Diagnosis of Left-Ventricular Noncompaction Cardiomyopathy in Identical Twins With Discordant Congenital Heart Disease

Left-ventricular noncompaction (LVNC) is characterized by prominent myocardial trabeculae with deep intratrabecular recesses. Associated with ventricular dysfunction, LVNC can present in isolation or in conjunction with structural heart defects (i.e., “nonisolated” LVNC). Although it was once considered to be difficult and unreliable, successful detection of this condition by way of fetal echocardiography has been well documented. We present what is to our knowledge the first prenatal diagnosis of LVNC in monochorionic-monozygotic twins. Nonisolated LVNC was identified in twins A and B at 23 weeks’ gestation. A noncompaction-to-compaction ratio >2 was documented in both cases. Discordance for congenital heart disease was observed in the twins: Twin A presented with pulmonary atresia with an intact ventricular septum, critical tricuspid stenosis, and severe right-ventricular hypoplasia, whereas twin B presented with mild mitral valve dysplasia. Despite an initially complicated postnatal course for twin A, this case shows that it is feasible to achieve good outcomes with accurate prenatal detection and aggressive postnatal management.     

Sinus Bradycardia, Wolff Parkinson White, and Left Ventricular Noncompaction

Left ventricular noncompaction (LVNC) is an uncommon disorder that has recently been recognized as a distinct cardiomyopathy. LVNC is thought to result from an arrest in the normal process of myocardial compaction. The association of Wolff-Parkinson-White with noncompaction of the left ventricle is well recognized. Sinus bradycardia has also been associated with LVNC, although less frequently than that of Wolff-Parkinson-White. We report an infant with LVNC, Wolff-Parkinson-White, and progressive sinus bradycardia who had a myocardial vascular abnormality in the region of the sinus node evident on autopsy. We propose that the progressive nature of the conduction system abnormality was as a result of abnormal angiogenesis.     

Beta-adrenergic influence on increased myocardial oxygen consumption during hypoxemia in awake newborn lambs

The purpose of this investigation was to determine the role of increased beta-adrenergic activity in regulating the increase in myocardial oxygen consumption that occurs during hypoxemia in unanesthetized newborn lambs. Through a left thoracotomy, fluid-filled catheters were placed in the ascending aorta, coronary sinus and left atrium, a pressure transducer was introduced into the left ventricle, and pacing wires were sutured onto the left atrium. The lambs were studied 3 d later by making intermittent measurements of aortic and coronary sinus blood oxygen saturations and Hb concentrations, left ventricular myocardial blood flow, cardiac output, heart rate, left atrial and aortic blood pressures, the maximal first derivative of left ventricular pressure, aortic and coronary sinus blood oxygen contents, the arteriovenous difference of oxygen across the left ventricular myocardium, myocardial oxygen consumption, and external cardiac work (aortic mean blood pressure times cardiac output). In nine lambs with an intact beta-adrenergic nervous system (group 1), the above measurements were made during a control period and during hypoxemia (FiO2 = 0.08-0.10) with spontaneous tachycardia. In another group of 12 lambs (group 2), the measurements were made during a control period, after beta-blockade (1.5 mg/kg intravenous propranolol) with pacing at the control heart rate, during hypoxemia with pacing at the control heart rate, and during hypoxemia with pacing-induced tachycardia. In the group 2 lambs, beta-blockade completely inhibited the increase in heart rate, maximal first derivative of left ventricular pressure, cardiac output and cardiac work that occurred during hypoxemia in the group 1 lambs that had an intact beta-adrenergic nervous system.(ABSTRACT TRUNCATED AT 250 WORDS)     

Bilateral coronary artery fistulas and left ventricle noncompaction in a neonate: diagnosis and management

This report describes a neonate with heart failure resulting from bilateral coronary artery fistulas and left ventricle noncompaction. The patient underwent successful surgical ligation of the fistulas.     

Myocardial noncompaction: report of three cases

Myocardial noncompaction is a rare type of cardiomyopathy which can be an isolated entity or in association with other congenital heart diseases. We present three children with myocardial noncompaction: one male with isolated left ventricular noncompaction, another with right ventricular noncompaction and dysplastic tricuspid valve, and the last with left ventricular noncompaction, ventricular septal defect and coarctation of aorta, to stress especially the different clinical forms of the disorder and the importance of early diagnosis, as it may result in a fatal outcome.     

Congenital left coronary artery — right ventricular fistula

ABSTRACT. The case of a neonate with heart failure and myocardial ischaemia due to a large coronary artery fistula is reported. ECG monitoring and Thallium — 201 imaging indicated pre-operative myocardial ischaemia. The diagnosis was confirmed by cardiac catheterization. Successful surgical ligation of the fistula was performed at the age of 10 days and to our knowledge is the first successful ligation in the neonatal period. Follow up Thallium — 201 imaging was normal. Repeat cardiac catheterization demonstrated complete closure of the fistula and normal left ventricular function.     

Coronary ischemia secondary to congenital anomaly of the left coronary artery

Coronary artery anomalies constitute 2.2 % of congenital malformations of the heart. The most common abnormality is anomalous origin of the left coronary artery from the pulmonary trunk, also known as Bland-White-Garland syndrome. Clinical manifestations are due to myocardial ischemia caused by the creation of an arteriovenous shunt. The childhood type of this anomaly presents high mortality from heart failure. The adult type develops myocardial infarction, arrhythmias, sudden cardiac death or signs of congestive heart failure. Surgical repair is essential. Various surgical approaches are available and the treatment of choice is direct left coronary artery reimplantation in the aorta. An alternative technique is to create an aortopulmonary tunnel (Takeuchi technique). Marked improvement is usually observed after surgical repair. We report two cases of myocardial ischemia due to coronary anomalies.     

Preliminary Data on the Diagnostic Accuracy of Rubidium-82 Cardiac PET Perfusion Imaging for the Evaluation of Ischemia in a Pediatric Population

Evaluation of myocardial perfusion is sometimes necessary in children with congenital heart disease or acquired coronary artery abnormalities. Limited information is available regarding the clinical utility of myocardial perfusion imaging in children. PET imaging with rubidium-82 may provide a convenient clinical means of assessing regional circulatory compromise in pediatric patients with small hearts, due to its improved spatial resolution. Clinically indicated cardiac PET studies obtained in 22 pediatric patients were reviewed by two blinded observers and assigned myocardial perfusion scores using a standard 17-segment model. PET results were correlated with coronary angiography, available in 15 cases, to determine the accuracy of PET scanning for evaluating compromise of the myocardial circulation. Reversible defects consistent with myocardial ischemia were present in 6 of 15 (40%) PET cases. The sensitivity and specificity of cardiac PET for the detection of significant coronary artery disease were 100% and 82%, respectively. The positive predictive value of cardiac PET was 67%, while the negative predictive value was 100%. Cardiac PET imaging with rubidium-82 appears promising for the noninvasive assessment of myocardial perfusion in the pediatric population. The findings from this small series suggest that prospective study in a larger patient cohort merits consideration.     

Complete Atresia of Coronary Ostia in Pulmonary Atresia and Intact Ventricular Septum

We describe the clinical course, echocardiography, angiography, and histopathology of a female infant with pulmonary atresia and intact ventricular septum (PA/IVS) with complete coronary ostial atresia and right ventricle-dependent coronary circulation who survived for 7 weeks after palliative surgery. The patient expired from myocardial insufficiency while waiting for a donor heart. Postmortem examination demonstrated atretic coronary ostia, ventricular sinusoids, and myocardial infarctions of various ages. This report suggests that neonates with PA/IVS who have this extreme form of coronary abnormality may potentially be managed medically and surgically until cardiac transplantation is available.     

CARDIOVASCULAR CAUSES FOR SUDDEN INFANT DEATH

Although sudden infant death syndrome (SIDS) is a cause for sudden infant death, other causes should be ruled out before diagnosing SIDS. Cardiac causes for sudden infant death include viral myocarditis, congential heart disease particularly congential aortic stenosis, endocardial fibroelastosis, and anomalous origin of the left coronary artery from the pulmonary artery. Other cardiac conditions that may result in sudden death include rhabdomyomas of the heart in tuberous sclerosis and conduction system disorders. The most frequent conduction system disorders resulting in sudden death include histiocytoid cardiomyopathy, congential heart block that may be associated with maternal lupus erythematosus, arrhythmogenic right ventricular dysplasia, noncompaction of the left ventricle, and long QT syndromes.     

A different type of cardiomyopathy: ventricular noncompaction (evaluation of 8 cases)

Ventricular noncompaction, characterized by numerous, prominent ventricular trabeculations and deep intratrabecular recesses, is thought to be due to an arrest of myocardial morphogenesis. We report eight patients with ventricular noncompaction diagnosed at our center in the previous one year. Two patients had associated congenital cardiac anomalies while the others were without coexisting cardiac abnormalities. Both ventricles were involved in one patient, only the right ventricle in one, and only the left ventricle in six patients. Seven patients had initially been diagnosed as having different types of cardiomyopathies. In conclusion, based on our limited experience, we propose that during the differential diagnosis of cardiomyopathies, ventricular noncompaction should be considered.     

Anomalous Origin of the Left Coronary Artery from the Pulmonary Artery (ALCAPA) Presenting as a Complete Heart Block

A 51-year-old previously asymptomatic man presented with complete heart block (CHB). During pacemaker implantation, fluoroscopy showed a peculiar pattern of cardiac calcification. Coronary angiography, performed to determine the origin of calcification, demonstrated an anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA). A left ventriculogram showed normal ventricular contraction. Echocardiography demonstrated normal systolic function without any regional wall motion abnormality. The endocardium of the mid and basal portions of the anteroseptal, anterior and anterolateral walls as well as both of the papillary muscles were calcified. Specifically noted was a calcific bar extending across the base of the interventricular septum (IVS) on both the echocardiogram and the left ventricle angiogram. The development of CHB in the absence of transmural myocardial infarction is intriguing. It is likely that endocardial fibroelastosis during infancy led to endocardial fibrosis and scarring subsequent calcium deposition. Extension of this calcification into the conduction system may have led to CHB. This is the first report of an adult patient with ALCAPA presenting with CHB.     

Coronary Vasospasm in an Adolescent Resulting from Marijuana Use

This report is the first to describe coronary vasospasm, diagnosed by cardiac magnetic resonance imaging in an adolescent, resulting from marijuana abuse. A previously healthy 17-year-old male patient with severe chest pain, electrocardiographic changes, and urine test positive for cannabis, was diagnosed of having transient myocardial ischemia. The patient was discharged home and at this writing remains asymptomatic with a follow-up echocardiogram after 1 month showing normal left ventricular systolic function. Marijuana should be considered in the etiology of transient coronary vasospasm leading to myocardial ischemia in otherwise healthy adolescents. Cardiac magnetic resonance imaging is a safe and effective method for diagnosing coronary vasospasm.     

Left Ventricular Noncompaction Cardiomyopathy in Barth Syndrome: An Example of an Undulating Cardiac Phenotype Necessitating Mechanical Circulatory Support as a Bridge to Transplantation

Barth syndrome (BTHS) is associated with myocardial disease, frequently left ventricular noncompaction cardiomyopathy, which may necessitate cardiac transplantation or lead to death in some patients. We report a child with BTHS who had an ??undulating cardiac phenotype?? and ultimately developed decompensated heart failure requiring mechanical circulatory support with a ventricular assist device as a bridge to transplantation. His course was complicated by acute lung injury requiring placement of an in-line oxygenator to maintain end-organ function. Not only was his course complicated by cardiac and respiratory failure but his BTHS associated comorbidities complicated the management of his therapy using mechanical assist device support. He was successfully supported and subsequently was transplanted. Here we discuss the management of a child with BTHS using mechanical circulatory support and describe the use of an in-line oxygenator, Quadrox, with the Berlin Excor device.