BACKGROUND

Observational studies have increasingly reported transthyretin amyloid cardiomyopathy (ATTR-CM) as an under-recognized cause of heart failure. We report the first ATTR-CM diagnosed via multi-modality imaging in the Philippines signifying an important milestone in recognition and management of this formerly believed rare disease, locally. Utilization of non-invasive imaging such as echocardiography, cardiac MRI and technetium-99m pyrophosphate scintigraphy (PYP) demonstrates the potential for accurate diagnosis as well as timely and appropriate treatment strategies.

An 81/M Filipino with a history of carpal tunnel surgery, post-percutaneous coronary intervention (PCI), had three months’ history of refractory heart failure symptoms despite optimized medical treatment. His 2D-echo showed an ejection fraction (EF): 45%-50%, increased left ventricular (LV) posterior wall thickness with mild basal inferior wall hypokinesia and ECG: atrial fibrillation with low voltage. Speckle tracking imaging showed average global longitudinal strain: - 6.5% with cherry-on-top pattern on polar strain map. Cardiac MRI demonstrated diffuse late gadolinium enhancement from endocardial to transmural layers of biventricular and biatrial walls, highly suggestive of cardiac amyloidosis (CA). Light-chain amyloidosis was excluded by negative serum/urine protein electrophoresis/immunofixation. Tc-99m PYP scan revealed greater myocardial-than-bone uptake with a Perugini score 3 and calculated heart-to-contralateral ratio of 1.7. Congestion was controlled with intravenous loop diuretics and he was discharged stable with metoprolol succinate, dapagliflozin and apixaban. At the time of paper submission, he is currently being evaluated for tafamidis treatment.

The case highlighted the advantage of multi-modality imaging for noninvasive yet accurate identification of the disease. A tailored approach is required in slowing the disease progression and improving outcomes.

Humans ; Amyloidosis ; Amyloid ; Cardiomyopathies

Humans ; Apical Hypertrophic Cardiomyopathy ; Heart Aneurysm/complications* ; Cardiomyopathy, Hypertrophic/complications* ; Ventricular Outflow Obstruction/etiology*

Humans ; Myocarditis/diagnostic imaging* ; Magnetic Resonance Imaging ; Myocardium ; Giant Cells

Adult ; Humans ; Myocarditis/therapy* ; Risk Factors

Humans ; Apical Hypertrophic Cardiomyopathy ; Heart Aneurysm/complications* ; Cardiomyopathy, Hypertrophic/complications* ; Ventricular Outflow Obstruction/etiology*

Humans ; Myocarditis/diagnostic imaging* ; Magnetic Resonance Imaging ; Myocardium ; Giant Cells

OBJECTIVE: To explore the clinical and genetic characteristics of a patient with hypertrophic cardiomyopathy as the initial manifestation of Mucopolysaccharidosis type Ⅲ A (MPS Ⅲ A). METHODS: A female patient with MPS Ⅲ A who was admitted to the Affiliated Hospital of Jining Medical University in January 2022 and her family members (seven individuals from three generations) were selected as the study subjects. Clinical data of the proband were collected. Peripheral blood samples of the proband was collected and subjected to whole exome sequencing. Candidate variants were verified by Sanger sequencing. Heparan-N-sulfatase activity was determined for the disease associated with the variant site. RESULTS: The proband was a 49-year-old woman, for whom cardiac MRI has revealed significant thickening (up to 20 mm) of left ventricular wall and delayed gadolinium enhancement at the apical myocardium. Genetic testing revealed that she has harbored compound heterozygous variants in exon 17 of the SGSH gene, namely c.545G>A (p.Arg182His) and c.703G>A (p.Asp235Asn). Based on guidelines from the American College of Medical Genetics and Genomics (ACMG), both variants were predicted to be pathogenic (PM2_Supporting +PM3+PP1Strong+PP3+PP4; PS3+PM1+PM2_Supporting +PM3+PP3+PP4). Sanger sequencing confirmed that her mother was heterozygous for the c.545G>A (p.Arg182His) variant, whilst her father, sisters and her son were heterozygous for the c.703G>A (p.Asp235Asn) variant. Determination of blood leukocyte heparan-N-sulfatase activity suggested that the patient had a low level of 1.6 nmol/(g·h), whilst that of her father, elder and younger sisters and son were all in the normal range. CONCLUSION The compound heterozygous variants of the SGSH gene probably underlay the MPS ⅢA in this patient, for which hypertrophic cardiomyopathy is an associated phenotype.
Female ; Humans ; Cardiomyopathy, Hypertrophic ; Contrast Media ; East Asian People ; Gadolinium ; Mucopolysaccharidosis III ; Mutation ; Pedigree ; Male ; Middle Aged

Objective To investigate the effect of viral myocarditis serum exosomal miR-320 on apoptosis of cardiomyocytes and its mechanism. Methods The model of viral myocarditis mice was established by intraperitoneal injection of Coxsackie virus B3. Serum exosomes were extracted by serum exosome extraction kit and co-cultured with cardiomyocytes. The uptake of exosomes by cardiomyocytes was detected by laser confocal microscopy. Cardiomyocytes were transfected with miR-320 inhibitor or mimic, and the expression level of miR-320 was detected by real-time quantitative PCR. Flow cytometry was used to detect cardiomyocyte apoptosis rate, and the expression levels of B cell lymphoma 2 (Bcl2) and Bcl2-related X protein (BAX) were tested by Western blot analysis. The prediction of miR-320 target genes and GO and KEGG enrichment analysis were tested by online database. The relationship between miR-320 and its target gene phosphoinositide-3-kinase regulatory subunit 1(Pik3r1) was examined by luciferase reporter gene. The effect of miR-320 on AKT/mTOR pathway protein was detected by Western blot analysis. Results Viral myocarditis serum exosomes promoted cardiomyocyte apoptosis, and increased the level of BAX while the level of Bcl2 was decreased. miR-320 was significantly up-regulated in myocardial tissue of viral myocarditis mice, and both pri-miR-320 and mature of miR-320 were up-regulated greatly in cardiomyocytes. The level of miR-320 in cardiomyocytes treated with viral myocarditis serum exosomes was significantly up-regulated, while transfection of miR-320 inhibitor counteracted miR-320 overexpression and reduced apoptosis rate caused by exosomes. Pik3r1 is the target gene of miR-320, and its overexpression reversed cardiomyocyte apoptosis induced by miR-320 up-regulation. The overexpression of miR-320 inhibited AKT/mTOR pathway activation. Conclusion Viral myocarditis serum exosome-derived miR-320 promotes apoptosis of mouse cardiomyocytes by inhibiting AKT/mTOR pathway by targeting Pik3r1.
Mice ; Animals ; Myocytes, Cardiac ; Phosphatidylinositol 3-Kinase/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Myocarditis/pathology* ; Exosomes/metabolism* ; bcl-2-Associated X Protein/metabolism* ; MicroRNAs/metabolism* ; TOR Serine-Threonine Kinases/metabolism* ; Apoptosis/genetics*

Hypertrophic cardiomyopathy (HCM) is the most common monogenic inherited myocardial disease in children, and mutations in sarcomere genes (such as MYH7 and MYBPC3) are the most common genetic etiology of HCM, among which mutations in the MYH7 gene are the most common and account for 30%-50%. MYH7 gene mutations have the characteristics of being affected by environmental factors, coexisting with multiple genetic variations, and age-dependent penetrance, which leads to different or overlapping clinical phenotypes in children, including various cardiomyopathies and skeletal myopathies. At present, the pathogenesis, course, and prognosis of HCM caused by MYH7 gene mutations in children remain unclear. This article summarizes the possible pathogenesis, clinical phenotype, and treatment of HCM caused by MYH7 gene mutations, in order to facilitate the accurate prognostic evaluation and individualized management and treatment of the children with this disorder.
Child ; Humans ; Cardiomyopathy, Hypertrophic/therapy* ; Phenotype ; Troponin T/genetics* ; Mutation ; Carrier Proteins/genetics* ; Myosin Heavy Chains/genetics* ; Cardiac Myosins/genetics*