Authors (including presenting author) :
Ling TK(1), Tseung JSB(1)(2), Yung CY(3), Wong CKW(1), Wong KL(3), Chang TL(1), Law CY(1), Fan KYY(3), Lam CW(1)(4)
Affiliation :
(1)Division of Chemical Pathology, Department of Pathology, Queen Mary Hospital,
Hong Kong SAR, China
(2) Department of Pathology, Princess Margaret Hospital, Lai Chi Kok, Hong Kong
SAR, China
(3) Department of Cardiac Medical Unit, Grantham Hospital, Wong Chuk Hang, Hong
Kong SAR, China
(4) Department of Pathology, University of Hong Kong, Hong Kong SAR, China
Introduction :
Inherited cardiomyopathies are a heterogeneous spectrum of disease. Phenotypic
presentation may include dilated cardiomyopathy, hypertrophic cardiomyopathy,
arrhythmogenic cardiomyopathy, restrictive cardiomyopathy etc. Underlying genetic
cause, if present, can be heterogeneous.
Objectives :
To delineate the spectrum of mutations in hereditary forms of cardiomyopathy and
arrhythmic disorder.
Methodology :
Cases referred from Grantham Hospital for genetic analysis of cardiomyopathy and
arrhythmic disorders between January 2021 and June 2022 were reviewed. Sequencing and
bioinformatics analysis was performed on Illumina NextSeq 2000. Appropriate virtual
gene panels would be selected based on the consent and phenotype of patients.
Result & Outcome :
A total of 26 patients had been included for this series. Dilated cardiomyopathy (DCM) was the major presenting phenotype (15/26 patients; 58%), with hypertrophic cardiomyopathy (HCM), arrhythmic disorders and heart failure in the remaining. Pathogenic or likely pathogenic variants were detected across 16 genes. In particular, single nucleotide deletion in FLNC gene was found in 5 patients from 2 families (c.3702del and c.5328del; both leading to frameshift and premature termination) with all 5 patients presenting with DCM. On the other hand, 4 different MYH7 missense variants were detected in 4 unrelated patients presenting with either DCM or HCM. FLNC-related cardiomyopathy is the major recurring cause of DCM in this series. This also highlighted the need of NGS-based sequencing technique for the diagnosis of this heterogeneous condition.
