Characterization of Left Ventricular Non-Compaction Cardiomyopathy

Abstract

Left ventricle non-compaction cardiomyopathy (LVNC) has gained great interest in recent years, being one of the most controversial cardiomyopathies. There are several open debates, not only about its genetic heterogeneity, or about the possibility to be an acquired cardiomyopathy, but also about its possible overdiagnosis based on imaging techniques. In order to better understand this entity, we identified 38 LVNC patients diagnosed by cardiac MRI (CMRI) or anatomopathological study that could underwent NGS-sequencing and clinical study. Anatomopathological exam was performed in eight available LVNC hearts. The genetic yield was 34.2%. Patients with negative genetic testing had better left ventricular ejection fraction (LVEF) or it showed a tendency to improve in follow-up, and a possible trigger factor for LVNC was identified in 1/3 of them. Nonetheless, cerebrovascular accidents occurred in similar proportions in both groups. We conclude that in LVNC there seem to be different ways to achieve the same final phenotype. Genetic testing has a good genetic yield and provides valuable information. LVNC without an underlying genetic cause may have a better prognosis in terms of LVEF evolution. However, anticoagulation to prevent cerebrovascular accident (CVA) should be carefully evaluated in all patients. Larger series with pathologic examination are needed to help better understand this entity.

Left Ventricular Noncompaction—A Systematic Review of Risk Factors in the Pediatric Population

“…Waning et al [ 9 ], in their systematic review on adults and children, outlined that the presence of mutations in some genes (such as MYBPC3, TTN, arrhythmia, and nonsarcomere nonarrythmia genes and X-linked genes) was associated with an increased risk of adverse events, whereas patients with most common mutations in MYH7 were at a lower risk. Furthermore, genetic testing may help outline patients at greater risk of severe heart failure because the presence of genetic mutations in genes associated with cardiomyopathies has been linked to lower ejection fraction [ 16 , 62 ]. In a study on adults and children, a greater number of genetic variants of interest (VOI) was associated with lower LVEF and greater NC/C ratio in MRI [ 63 ].…”

Excessive Trabeculation of the Left Ventricle

“… 54 Greater hypertrophy of the cardiomyocytes in the trabecular than compact layers, nonetheless, has been reported in explanted hearts. 56 Therefore, evidence to date suggests that trabecular and compact cardiomyocytes are similar, although differences may exist in their responses to different pathologic and physiological processes.…”

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

“…However, according to the literature, 65.8% of the NVM patients have negative genetic testing results [ 19 ]. Recent data proposed additional etiopathogenic mechanisms, including acquired forms of LVNC secondary to overloading conditions [ 20 – 22 ].…”