Given the initial clinical presentation, history of pneumonia, and echocardiographic findings at admission, we should differentiate between the most common types of dilative cardiomyopathy (DCM): post myocarditis, idiopathic cardiomyopathy, LV non-compaction (LVNC), or ischemic heart disease.

A positron emission tomography scan (PET) was performed to assess myocardial perfusion and viability. PET findings were very similar to those of ischemic cardiomyopathy (Figure S1). Coronary angiography revealed normal coronary anatomy. The left ventriculography confirmed the diagnosis of DCM. To clarify the etiology of cardiomyopathy endomyocardial biopsy was performed. Histology showed diffuse cardiac fibrosis, typical of DCM. Myocardial tissue samples were tested for the presence of enteroviral sequences by a polymerase chain reaction, yielding negative results. Cardiovascular magnetic resonance (Figure 1D–F) was done for further evaluation of cardiac function and volume.

Genetic and family screening is important for the correct diagnosis and prognosis. Genetic analysis was performed with a new generation sequencing techniques and showed two missense mutations in the titin gene c.54703C>T (p.Arg18235Cys), and c.47090G>C (p.Arg15697Pro) — a novel variant, not described in the literature, and a dominant missense mutation in the Filamin C gene 5071G>A (p.Asp1691Asn). Titin has been recently reported to be associated with LVNC. Titin truncating variants are prevalent, but there are data for pathogenic missense variants [1]. Мutations in these genes were associated with DCM and hypertrophic cardiomyopathy [2, 3]. Тhis is the first reported clinical case with these variants of mutations and LVNC. Screening echocardiography of the patient’s relatives was done, showing no signs of cardiomyopathy.

The patient was treated following the recommendations for heart failure management [4].

At the follow-up visit on the third month, he still had persistent LV systolic dysfunction yet without any signs of heart failure.

LVNC is an uncommon myocardial disorder. Clinical presentation with a classical triad (heart failure, arrhythmias, and thromboembolism) is very rare [5]. This case is an example of the heterogeneity and overlapping between the different types of cardiomyopathies. This was a patient with symptoms of decompensated heart failure, with a history of a recent severe inflammatory disease (differential diagnosis: DCM after myoraditis) and imaging tests specific for the DCM with LVNC. Even if an accurate diagnosis does not lead to improvement of patients prognosis currently, the detection of a hereditary component of the disease and subsequent screening of relatives can help identify first-line relatives at risk.

Article information

Conflict of interest: None declared.

Funding: This work was supported by Medical University Sofia, Bulgaria (grant, number 8374).

Open access: This article is available in open access under Creative Common Attribution-Non-Commercial-No Derivatives 4.0 International (CC BY-NC-ND 4.0) license, allowing to download articles and share them with others as long as they credit the authors and the publisher, but without permission to change them in any way or use them commercially. For commercial use, please contact the journal office at kardiologiapolska@ptkardio.pl.

How to cite: Shumkova M, Vassilev D, Karamfiloff K, et al. Left ventricle non-compaction with a dilative phenotype and novel genetic mutations. Kardiol Pol. 2021; 79(6): 716–717, doi: 10.33963/KP.15965.

REFERENCES