Phenotype/Genotype Relationship in Left Ventricular Noncompaction: Ion Channel Gene Mutations Are Associated With Preserved Left Ventricular Systolic Function and Biventricular Noncompaction: Phenotype/Genotype of Noncompaction
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Patients
From 2012 to 2013, 95 patients newly diagnosed with LVNC were included. This study complies with the Declaration of Helsinki and was approved by our institutional review board. Written informed consent was obtained from all patients. Since the end of the inclusion period (2013), 16 additional new cases of ion channel gene mutations were identified, giving a total of 111 patients with LVNC. Finally, the echocardiographic characteristics of 30 patients with channel gene mutations were compared
Analysis of the Data From the Registry
Characteristics at diagnosis of the 95 unrelated patients with LVNC are presented in Supplementary Table 1. Mean age at diagnosis was 47.0 ± 15.4 years, and 54 patients (56.8%) were male. The median LVEF was 41% (interquartile range, 32–57), 32 patients (34%) had an LVEF of 50% or greater and 19 patients (20%) had an LVEF of less than 30%. The median number of NC segments was 5 (interquartile range, 4–6) and the mean NC/compacted ratio in end-systole was 2.2 ± 0.3. The most frequent
Discussion
LVNC is a rare cardiomyopathy characterized by clinical and genetic heterogeneity. Recent studies reported that mutations in the HCN4 gene could be associated with LVNC.2, 3, 4 However, the significance of such mutations has been debated6, 7, 8, 9 and if those patients present with a different phenotype than other patients with LVNC is unknown.
We recently reported our experience of a targeted panel sequencing in a prospective series of LVNC and found that LVNC was basically a genetic disease in
Conclusions
Ion channel mutations should be systematically searched in patients with LVNC associated with biventricular noncompaction, particularly when LV systolic function is preserved. HCN4 mutation should be particularly suspected in the presence of additional bradycardia. Identifying causative mutations is of utmost importance for genetic counselling in at-risk relatives of patients affected by LVNC.
Conflict of Interest Statement
None.
Financial Disclosure
None.
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
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Cited by (0)
Supported by grants from the PHRC (projet hospitalier de recherche clinique) PHRC 2011-A-00987-34.
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Marie Cambon-Viala, Hilla Gerard, and Karine Nguyen equally contributed to the paper and are equal first authors.
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Gilbert Habib and Philippe Charron are equal last authors.