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Background: Brugada syndrome (BrS) is an inherited primary channelopathy syndrome associated with the risk of ventricular fibrillation (VF) and sudden cardiac death in a structurally normal heart., Aim of the Study: The aim of this study was to clinically and genetically evaluate a large family with severe autosomal dominant Brugada syndrome., Methods: Clinical and genetic studies were performed. Genetic analysis was conducted with NGS technologies (WES) using the Illumina instrument. According to the standard procedure, variants found by WES were confirmed in all available families by Sanger sequencing. The effect of the variants was studied by using in silico prediction of pathogenicity., Results: The proband was a 52-year-old man who was admitted to the emergency department for syncope at rest. WES of the index case identified a heterozygous VUS CASQ2 , c.532T>C, p.(Tyr178His). We studied the segregation of the variation in all pedigree members. All the patients were heterozygous for the variation CASQ2 p.(Tyr178His), whereas the remaining healthy individuals in the family were homozygous for the normal allele. Structural analysis of CASQ2 p.(Tyr178His) was performed and revealed an important effect of the missense variation on monomer stability. The CASQ2 Tyr180 residue is located inside the sarcoplasmic reticulum (SR) junctional face membrane interaction domain and is predicted to disrupt filamentation., Conclusions: Our data suggest that the p.Tyr178His substitution is associated with BrS in the family investigated, affecting the stability of the protein, disrupting filamentation at the interdimer interface, and affecting the subsequent formation of tetramers and polymers that contain calcium-binding sites.

Background: Neurological disorders as a risk factor for Takotsubo syndrome (TTS) are not well characterized. The aim of the study was to evaluate TTS-associated neurological phenotypes and outcome., Methods and Results: Patients with TTS enrolled in the international multicenter GEIST (German Italian Spanish Takotsubo) registry were analyzed. Prevalence, clinical characteristics, and short- and long-term outcomes of patients with TTS were recorded. A subgroup analysis of the 5 most represented neurological disorders was performed. In total, 400 (17%) of 2301 patients had neurological disorders. The most represented neurological conditions were previous cerebrovascular events (39%), followed by neurodegenerative disorders (30.7%), migraine (10%), epilepsy (9.5%), and brain tumors (5%). During hospitalization, patients with neurological disorders had longer in-hospital stay (8 [interquartile range, 5-12] versus 6 [interquartile range, 5-9] days; P <0.01) and more often experienced in-hospital complications (27% versus 16%; P =0.01) mainly driven by cardiogenic shock and in-hospital death (12% versus 7.6% and 6.5% versus 2.8%, respectively; both P <0.01). Survival analysis showed a higher mortality rate in neurological patients both at 60 days and long-term (8.8% versus 3.4% and 23.5% versus 10.1%, respectively; both P <0.01). Neurological disorder was an independent predictor of both the 60-day and long-term mortality rate (odds ratio, 1.78 [95% CI, 1.07-2.97]; P =0.02; hazard ratio, 1.72 [95% CI, 1.33-2.22]; both P <0.001). Patients with neurodegenerative disorders had the worst prognosis among the neurological disease subgroups, whereas patients with TTS with migraine had a favorable prognosis (long-term mortality rates, 29.2% and 9.7%, respectively)., Conclusions: Neurological disorders identify a high-risk TTS subgroup for enhanced short- and long-term mortality rate. Careful recognition of neurological disorders and phenotype is therefore needed.

Background Takotsubo syndrome is usually triggered by a stressful event. The type of trigger seems to influence the outcome and should therefore be considered separately. Methods and Results Patients included in the GEIST (German-Italian-Spanish Takotsubo) registry were categorized according to physical trigger (PT), emotional trigger (ET), and no trigger (NT) of Takotsubo syndrome. Clinical characteristics as well as outcome predictors were analyzed. Overall, 2482 patients were included. ET was detected in 910 patients (36.7%), PT in 885 patients (34.4%), and NT was observed in 717 patients (28.9%). Compared with patients with PT or NT, patients with ET were younger, less frequently men, and had a lower prevalence of comorbidities. Adverse in-hospital events (NT: 18.8% versus PT: 27.1% versus ET: 12.1%, P <0.001) and long-term mortality rates (NT: 14.4% versus PT: 21.6% versus ET: 8.5%, P <0.001) were significantly lower in patients with ET. Increasing age ( P <0.001), male sex ( P =0.007), diabetes ( P <0.001), malignancy ( P =0.002), and a neurological disorder ( P <0.001) were associated with a higher risk of long-term mortality, while chest pain ( P =0.035) and treatment with angiotensin-converting enzyme inhibitor/angiotensin receptor blocker ( P =0.027) were confirmed as independent predictors for a lower risk of long-term mortality. Conclusions Patients with ET have better clinical conditions and a lower mortality rate. Increasing age, male sex, malignancy, a neurological disorder, chest pain, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, and diabetes were confirmed as predictors of long-term mortality.

Background: Brugada syndrome (BrS) is an inherited primary channelopathy syndrome associated to sudden cardiac death. Overall, variants have been identified in eighteen genes encoding for ion channel subunits and seven genes for regulatory proteins. Recently, a missense variant in DLG1 has been found within a BrS phenotype-positive patient. DLG1 encodes for synapse associated protein 97 (SAP97), a protein characterized by the presence of multiple domains for protein-protein interactions including PDZ domains. In cardiomyocytes, SAP97 interacts with Nav1.5, a PDZ binding motif of SCN5A and others potassium channel subunits., Aim of the Study: To characterize the phenotype of an Italian family with BrS syndrome carrying a DLG1 variant., Methods: Clinical and genetic investigations were performed. Genetic testing was performed with whole-exome sequencing (WES) using the Illumina platform. According to the standard protocol, a variant found by WES was confirmed in all members of the family by bi-directional capillary Sanger resequencing. The effect of the variant was investigated by using in silico prediction of pathogenicity., Results: The index case was a 74-year-old man with spontaneous type 1 BrS ECG pattern that experienced syncope and underwent ICD implantation. WES of the index case, performed assuming a dominant mode of inheritance, identified a heterozygous variant, c.1556G>A (p.R519H), in the exon 15 of the DLG1 gene. In the pedigree investigation, 6 out of 12 family members had the variant. Carriers of the gene variant all had BrS ECG type 1 drug induced and showed heterogeneous cardiac phenotypes with two patients experiencing syncope during exercise and fever, respectively. The amino acid residue #519 lies near a PDZ domain and in silico analysis suggested a causal role for the variant. Modelling of the resulting protein structure predicted that the variant disrupts an H-bond and a likelihood of being pathogenic. As a consequence, it is likely that a conformational change affects protein functionality and the modulating role on ion channels., Conclusions: A DLG1 gene variant identified was associated with BrS. The variant could modify the formation of multichannel protein complexes, affecting ion channels to specific compartments in cardiomyocytes.