Isolated right ventricular noncompaction in a newborn

Sudden unexpected intrapartum death and left ventricular noncompaction involving the right ventricle

Left ventricular noncompaction (LVNC), involving mainly the right ventricle, is a rare form of congenital heart disorder characterized by a developmental arrest in myocardial compaction, resulting in a spongy appearance of the myocardium, mainly of the right ventricle, rarely detected in fetuses. We report the case of a female fetus with a gestational age of 41+4 weeks who came to our attention for intrapartum sudden unexpected death, resulting in stillbirth. The ventricular walls, particularly the right ventricular wall, appeared thick, hypertrabeculated and spongy, leading to the diagnosis of LVNC involving mainly the right ventricle. The atrioventricular node and His bundle presented areas of fetal dispersion and resorptive degeneration; islands of conduction tissue were detected in the central fibrous body. Arcuate nucleus of the brainstem showed bilateral severe hypoplasia. The right bundle branch was hypoplastic. The final cause of death was an electrical conduction disfunction in an LVNC involving mainly the right ventricle. To the best of our knowledge, the herein described case is the first reported observation of sudden intrapartum death from LVNC involving mainly the right ventricle well documented post-mortem with cardiac conduction and brainstem studies. Our findings confirm the need of an accurate post-mortem examination including the study of the cardiac conduction system on serial section in every case of sudden unexpected fetal death, although there are no universally recognized guidelines.

A case report of isolated right ventricular noncompaction with mutation of ACVRL1: a new cause of noncompaction of ventricular myocardium?

BACKGROUND

Noncompaction of ventricular myocardium(NVM) is a rare kind of cardiomyopathy associated with genetic mutations and nongenetic factors, among which the isolated right ventricular noncompaction (iRVNC) is the most rare type. ACVRL1 is the pathogenic gene of type 2 hereditary hemorrhagic telangiectasia (HHT2), and there's no NVM reported to be associated with ACVRL1 mutation.

CASE PRESENTATION

This is a rare case diagnosed as iRVNC and pulmonary hypertention with ACVRL1 mutation detected.

CONCLUSION

iRVNC in this case may be due to ACVRL1 mutation, secondary to pulmonary hypertention and right ventricular failure caused by ACVRL1 mutation, or they happened in the same case coincidently.

Prenatal Diagnosis of Isolated Right Ventricular Non-Compaction Cardiomyopathy with an MYH7 Likely Pathogenic Variant

Background: Noncompaction of ventricular myocardium is a cardiomyopathy that typically involves the left ventricle or both ventricles; it has often been associated with mutations in genes encoding sarcomere proteins. Little is known about isolated right ventricular noncompaction, as only a few cases have been reported. Case Report: A 30 year old G2P1 woman experienced a spontaneous fetal loss at 19 weeks and 4 days. An ultrasound examination at 19 weeks showed right ventricular and tricuspid valve abnormalities, ascites, and early hydrops. At autopsy, the right ventricular chamber was dilated with numerous prominent trabeculations and deep intrabecular recesses as well as a dysplastic tricuspid valve. Histologic examination confirmed isolated right ventricular noncompaction. Whole exome sequencing showed a likely pathogenic variant in the MYH7 gene. Conclusions: This appears to be the first report of isolated right ventricular noncompaction associated with a gene mutation as well as the first diagnosis in a fetus.

Use of Cardiac MRI in the Diagnosis of Rare Right Ventricular Noncompaction

Ventricular noncompaction, also previously known as spongy myocardium, is an inherited primary genetic cardiomyopathy. Noncompaction of the left ventricle is seen in the general population typically in the setting of other congenital heart defects and can be a cause of significant morbidity and mortality. Right ventricular noncompaction is a rare form of cardiomyopathy with no definitive diagnostic criteria. Diagnosis of noncompaction of the right ventricle can be concluded using guidance from the diagnostic criteria for left ventricular noncompaction with multi-modality imaging.

Cardiac Segmental Strain Analysis in Pediatric Left Ventricular Noncompaction Cardiomyopathy

BACKGROUND

Left ventricular noncompaction cardiomyopathy (LVNC) is characterized by prominent left ventricular trabeculations, often leading to myocardial dysfunction and death or heart transplantation. Although diagnostic echocardiographic criteria exist for LVNC, segmental speckle-tracking strain patterns have not been described in pediatric LVNC. The objectives of this study were to characterize segmental noncompaction, evaluate segmental speckle-tracking strain, and characterize peak strain values in children with LVNC with adverse clinical outcomes.

METHODS

Echocardiographic noncompaction/compaction ratios and segmental radial, circumferential, and longitudinal strain were measured retrospectively in children with LVNC (January 2000 to June 2013). Segmental strain of the cohort was compared with that in control subjects matched by age and body surface area.

RESULTS

One hundred one pediatric patients with LVNC were included (median age 2.8 years; range, 0-19.4 years); 71 patients survived (benign group) and 30 patients did not survive or required heart transplantation (adverse group). The adverse group was younger at diagnosis (P = .03), with lower ejection fractions (P < .0001) compared with the benign group. Both groups demonstrated increased noncompaction/compaction ratios within apical segments, with significantly increased involvement in antero- and inferolateral midpapillary segments in the adverse group (P < .005). Radial, circumferential, and longitudinal strain of nearly all left ventricular segments were significantly decreased in the adverse compared with the benign group and in pediatric LVNC patients compared with control subjects. Global radial (7.4 ± 9.7% vs 19.6 ± 16.5%, P < .0001), circumferential (-8.4 ± 7.0% vs -18.9 ± 6.9%, P < .0001), and longitudinal (-7.1 ± 5.2% vs -11.8 ± 5.3%, P < .0001) strain were all significantly decreased in the adverse group compared with the benign group.

CONCLUSIONS

Segmental radial, circumferential, and longitudinal strain are decreased in pediatric patients with LVNC compared with control subjects and lowest in those with adverse compared with benign outcomes. LVNC appears to be a global disease affecting deformation in all regions, including compacted myocardial segments.

Clinical findings in right ventricular noncompaction in hypoplastic left heart syndrome

BACKGROUND

Noncompaction is a poorly understood form of cardiomyopathy that typically affects the left ventricle and may be associated with congenital heart disease. Right ventricular noncompaction (RVNC) may occur when the left ventricle is affected but is rarely seen in isolation. RVNC may have clinical significance affecting surgical and long-term outcomes. We describe the diagnosis and clinical course in three patients at our institution.

METHODS

We performed a retrospective review of patients diagnosed with RVNC over a 12-month period at our institution and reviewed their imaging and clinical course.

RESULTS

Three patients were identified. All had diagnosis of RVNC by echocardiography (echo) made on postnatal imaging which reviewed degree of trabeculation, and noncompaction-to-compaction ratio of the myocardium. Patient A was a neonate with hypoplastic left heart syndrome (HLHS) who underwent a Norwood operation with Sano modification. Her postoperative course was notable for low-normal RV function. She returned with a pericardial effusion warranting immediate pericardiocentesis. She continued to have effusions, which were medically managed. She was subsequently found to have an RV apical pseudoaneurysm, which required surgical resection. Patient B was a neonate with HLHS who had a Norwood operation with Sano modification. She had low-normal RV function on echo. She required medical management for pericardial effusion. Patient C was a neonate with HLHS who also underwent a Norwood operation with Sano modification. His postoperative course was notable for elevated serum brain natriuretic peptide, which was treated with digoxin.

CONCLUSION

RVNC is a rare diagnosis with limited known clinical impact. One of these patients had a very rare complication after pericardiocentesis (pseudoaneurysm) that may have been related to the RVNC. Our understanding of this disease process is limited and requires additional investigation, but emphasizes the importance of appropriate diagnosis to allow for timely follow-up and counseling for this unique population.

Left Ventricular Non-compaction: Is It Genetic?

Left ventricular non-compaction (LVNC) is reported to affect 0.14 % of the pediatric population. The etiology is heterogeneous and includes a wide number of genetic causes. As an illustration, we report two patients with LVNC who were diagnosed with a genetic syndrome. We then review the literature and suggest a diagnostic algorithm to evaluate individuals with LVNC. Case 1 is a 15-month-old girl who presented with hypotonia, global developmental delay, congenital heart defect (including LVNC) and facial dysmorphism. Case 2 is a 7-month-old girl with hypotonia, seizures, laryngomalacia and LVNC. We performed chromosomal microarray for both our patients and detected chromosome 1p36 microdeletion. We reviewed the literature for other genetic causes of LVNC and formulated a diagnostic algorithm, which includes assessment for syndromic disorders, inborn error of metabolism, copy number variants and non-syndromic monogenic disorder associated with LVNC. LVNC is a relatively newly recognized entity, with heterogeneity in underlying etiology. For a systematic approach of evaluating the underlying cause to improve clinical care of these patients, a diagnostic algorithm for genetic evaluation of patients with LVNC is proposed.

Noncompaction of Ventricular Myocardium Involving the Right Ventricle

Noncompaction ventricular myocardium is an unusual cause of cardiomyopathy. It is association with congenital heart defects, most often with outflow obstructive lesions or coronary anomalies. However, no factor could explain the arrest of development of myocardial structure (isolated form). The pathogenesis of isolated noncompaction is thought to be an arrest in endomyocardial morphogenesis. It has been reported that myocardial noncompaction could present as acquired disease. The most common site of involvement is the left ventricle, with right ventricular involvement being reported in a few cases. In this report, we present a case with noncompaction of the right ventricle (RV). Cardiac computed tomography angiography and magnetic resonance imaging demonstrated morphological abnormalities of the RV.