Hypertrophic cardiomyopathy is a common genetic heart disease and up to 40%-60% of patients have mutations in cardiac sarcomere protein genes. This genetic diagnosis study aimed to detect pathogenic or likely pathogenic sarcomeric and non-sarcomeric gene mutations and to confirm a final molecular diagnosis in patients diagnosed with hypertrophic cardiomyopathy. A total of 392 patients with hypertrophic cardiomyopathy were included in this nationwide multicenter study conducted at 23 centers across Türkiye. All samples were analyzed with a 17-gene hypertrophic cardiomyopathy panel using next-generation sequencing technology. The gene panel includes ACTC1, DES, FLNC, GLA, LAMP2, MYBPC3, MYH7, MYL2, MYL3, PLN, PRKAG2, PTPN11, TNNC1, TNNI3, TNNT2, TPM1, and TTR genes. The next-generation sequencing panel identified positive genetic variants (variants of unknown significance, likely pathogenic or pathogenic) in 12 genes for 121 of 392 samples, including sarcomeric gene mutations in 30.4% (119/392) of samples tested, galactosidase alpha variants in 0.5% (2/392) of samples and TTR variant in 0.025% (1/392). The likely pathogenic or pathogenic variants identified in 69 (57.0%) of 121 positive samples yielded a confirmed molecular diagnosis. The diagnostic yield was 17.1% (15.8% for hypertrophic cardiomyopathy variants) for hypertrophic cardiomyopathy and hypertrophic cardiomyopathy phenocopies and 0.5% for Fabry disease. Our study showed that the distribution of genetic mutations, the prevalence of Fabry disease, and TTR amyloidosis in the Turkish population diagnosed with hypertrophic cardiomyopathy were similar to the other populations, but the percentage of sarcomeric gene mutations was slightly lower.

Introduction: In chronic venous insufficiency (CVI), an increase in venous pressure causes the passage of intravascular blood cells and molecules into the surrounding tissues and induces histopathological changes in the lower extremities, leading to increased pigmentation in the legs, ulceration, and tissue loss to various degrees. This study aimed to investigate whether an increase in venous pressure in the coronary veins can lead to the aforementioned histopathological changes.Material and methods: Twenty-four New Zealand rabbits were divided into the following three groups: experimental model of coronary venous hypertension (CVH) (n = 8), sham group (n = 8), and control group (n = 8). After 21 days postoperatively, tissue samples from each group were compared for perivascular inflammation, erythrocyte extravasation, macrophage infiltration, and hemosiderin deposits by histopathological scoring under a light microscope. Matrix metalloproteinase-2 (MMP-2) activation was evaluated using immunohistochemical staining.Results: In the CVH group, hemosiderin accumulation was significantly higher than in the sham and control groups (1.0 (1.0–3.0), 0.0 (0.0–1.0), 0.0 (0.0–0.0); p < 0.001). Immunohistochemically, in the CVH group, MMP-2 levels were significantly higher than in the sham and control groups (2.0 (1.0–3.0), 0.0 (0.0–1.0), 0.0 (0.0–0.0); p < 0.001).Conclusions: This experimental study showed for the first time the histopathological and immunohistochemical changes in myocardial tissue, similar to those observed in CVI, as a result of increased coronary venous pressure due to coronary vein ligation. Further studies are needed to understand the clinical implications of these results.

KEY WORDS: Chest pain; Angina pectoris; Myocardial ischemia

Contradictory Effect of Coronary Collateral Circulation on Regional Myocardial Perfusion That Assessed by Quantitative Myocardial Perfusion Scintigraphy